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  • 1965-1969  (3,184)
  • 1890-1899  (2,182)
  • Organic Chemistry  (5,311)
  • Cat  (55)
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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 128 (1969), S. 222-234 
    ISSN: 1432-0568
    Keywords: Postnatal development ; Fixation ; Neuroglia ; Corpus callosum ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die Gehirne von Tieren aus 4 verschieden alten Würfen junger Katzen wurden teils lebensfrisch durch Perfusion, teils nach 24 Std durch Immersion fixiert und für Vergleichsuntersuchungen in Paraffin eingebettet. Bei Betrachtung der Gliazellen des Corpus callosum ergab sich: 1. Nach Perfusionsfixierung sind die Kerne der Gliazellen groß und elliptisch. Sie sind wasserklar und haben eine scharf gezeichnete Chromatinstruktur. Nach Immersionsfixierung 24 Std p.m. sind die Kerne dagegen klein und rund, homogen dunkel gefärbt und haben ein kaum zu erkennendes Chromatingerüst. 2. Nach Perfusionsfixierung sieht man im Balken der ganz jungen Tiere zahlreiche Mitosen. Sie fehlen bei den durch Immersion fixierten Geschwistertieren desselben Wurfes. 3. Die nach verschiedener Fixierung beobachteten Unterschiede in der Form der Gliazellkerne werden durch Messungen der Quer- und Längsachsen erfaßt.
    Notes: Summary In four litters of young cats, some of the brains were fixed by perfusion and the others by immersion. The material was embedded in paraffin and the neuroglia was investigated in sections through the corpus callosum. It was found that: 1. After fixation by perfusion the nuclei of the glia cells are large and elliptic. The caryoplasm is clear and there is a distinct structure of the chromatin. After fixation by immersion the nuclei of the same cells are small and round. The caryoplasm is dense and the structure of the chromatin is not clearly visible. 2. After fixation by perfusion mitotic figures are present. They are absent in the brains fixed by immersion. 3. Following different fixation, there are differences in the shape of the nuclei of the glial cells. These differences have been investigated in detail by measuring the diameters of the nuclei.
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 128 (1969), S. 28-39 
    ISSN: 1432-0568
    Keywords: Arterial supply ; Corpus callosum ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung An 27 Katzen beiderlei Geschlechts wurde die Blutversorgung des Corpus callosum untersucht. Dabei wurden folgende Befunde erhoben: Der Balken der Katze wird im Bereich des Rostrum und Genu sowie im vorderen und mittleren Truncuabschnitt aus der Arteria cerebri anterior versorgt und zwar über Äste, die den Arteriae pericallosae und den Arteriae genu corporis callosi entstammen. Diese Äste wurden als Arteriae callosi superiores und inferiores bezeichnet. Lediglich im hinteren Truncusabschnitt und im Splenium erfolgt die Versorgung neben Ästen der A. pericall. auch über solche der Arteriae cerebri mediae und posteriores. Die Blutgefäße treten dolchartig in den Balken ein, teilen sich dann baumartig weiter auf und gehen in ein Capillarnetz über, das in Richtung des Nervenfaserverlaufes ausgezogen ist. Auf in der Literatur bereits bekannte, aber oft vernachlässigte Besonderheiten der Arteria carotis interna und des Circulus arteriosus wird hingewiesen.
    Notes: Summary In investigations on 27 cats of both sexes, the arterial supply of the corpus callosum was studied. The findings are as follows: In the region comprising rostrum and genu as well as in the fore and middle trunk sections, blood supplied by branches of the arteriae pericallosae and the arteriae genu corporis callosi which originate from the arteria cerebri anterior. These branches were designated arteriae callosi superiores and inferiores. However, in the posterior section of the trunk and in the splenium the blood is supplied by branches of the aa. pericall. and, in addition, by branches of the arteriae cerebri media and posteriores. The blood vessels penetrate the corpus callosum in bayonet fashion, then arborise and finally become a capillary network which is elongated in the direction of the course of the nerve fibres. Attention is drawn to peculiarities of the arteria carotis interna and the circle of Willis which, although known in the literature, are rarely referred to.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Experimental brain research 8 (1969), S. 113-129 
    ISSN: 1432-1106
    Keywords: Emotional behaviour ; Hypothalamus ; Electrical stimulation ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. Affective behaviour patterns produced by electrical stimulation of the hypothalamus were studied in unanaesthetized, freely-moving cats. Bipolar stimulation with coaxial electrodes and small cathode was used to elicit defence, attack or flight. The development of these responses was studied by varying stimulation strength. In some experiments a stuffed animal was introduced in order to study the reactions of the cat to changes in the environment during stimulation. 2. The following responses were evoked at threshold intensity: (i) growling reaction; (ii) hissing reaction; (iii) two types of flight — type a preceded by hastily looking to and fro as if in search of an exit, type b preceded by inspection of surroundings, in most cases associated with sniffing. 3. Increasing stimulation 1.5 times threshold often yielded combined patterns. At points yielding the growling reaction a defence response in which growls alternated with hisses was obtained. The points yielding flight type a sometimes yielded hissing followed by flight. Increasing stimulation at hissing points yielded either a defence reaction or the combined effect hissing-flight. 4. The growling reactions were obtained from the tuber region. The hissing responses were obtained from points above the tuber. The flight reactions, type a, were produced from the intermediate zone extending from the level of the preoptic area to the mamillary bodies and type b from the caudo-lateral hypothalamus. 5. The reactions of the cats to a dummy during stimulation varied depending on the type of response which had been evoked in the absence of the dummy. The defence reaction was converted into threatening and striking of the dummy, the combined effects into threatening, striking or biting, culminating in sudden flight. The dummy was ignored during stimulation of points yielding flight type a, but examined by sniffing during stimulation of points yielding flight type b.
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  • 4
    ISSN: 1432-1106
    Keywords: Emotional Behaviour ; Hypothalamus ; Electrical stimulation ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. The results presented in the present paper are an extension of preceding work devoted to exploration of the hypothalamic defence and flight fields using coaxial electrodes with small cathode. In 33 cats simultaneous stimulation was applied to two points which upon single stimulation had yielded defence, flight, or defence and flight respectively. Results were compared with those produced at either point alone. In 2 cats combined stimulation of a defence and a flight point was carried out with a stuffed cat present. 2. The latencies and rates of the vocal effects associated with defence (growling and hissing), and the latencies of flight (jump from the table) were measured. 3. Simultaneous stimulation of two points which had yielded defence, or of two points which had yielded flight resulted in facilitation (spatial summation) of the effects evoked: a more complete defence response associated with decrease of the latencies and increase in the rates of the vocal effects; decrease of flight latencies and increase of flight impetuosity. 4. Simultaneous stimulation of a defence point which had yielded growling at lower threshold than hissing, and of a point which had yielded flight resulted in facilitation of hissing. Growling and flight were often suppressed; when they occurred, latencies were lengthened and growling rates were increased somewhat. 5. Stimulation of a defence point with a dummy present produces striking (fending off). Simultaneous stimulation of a flight point resulted in facilitation of both hissing and striking. 6. It is concluded that the complex patterns obtained when defence is combined with flight are the result of facilitatory and inhibitory interaction between the elements of the individual patterns.
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Experimental brain research 8 (1969), S. 37-52 
    ISSN: 1432-1106
    Keywords: Retinal Ganglion Cells ; Spatial Summation ; Center Inhibition ; Dynamic Organisation of Receptive Fields ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung 1. An retinalen Ganglienzellen der Katze wurde die räumliche Summation im receptiven Feldzentrum (KFZ) bei Dunkeladaptation und Helladaptation durch mittelpunktzentrierte Lichtreize verschiedener Flächengrößen untersucht. Als Kriterium dienten die Entladungsraten der ersten 200 und 500 msec nach Licht-an oder Licht-aus. Das Summationsverhalten wurde sowohl für Einzelneurone als auch gruppenstatistisch für die beiden Neuronen-Systeme B (on-Zentrum) und D (off-Zentrum) untersucht. 2. Die räumliche Summation ist auf den inneren Bereich des RFZ beschränkt: bei on-Zentrum-Neuronen steigt die Entladungsrate nur bis zu Reizflächen, die etwa 1/5 der Fläche des RFZ belichten, bei off-Zentrum-Neuronen bis zu Reizflachen von ca. 1/10 des RFZ. Bei Variation der Reizfläche zwischen 20 und 100% der Fläche des RFZ bleibt das Entladungsniveau konstant (asymptotischer Verlauf der Summationskurve). 3. Die Begrenzung der räumlichen Summation auf einen kleinen Bereich des RFZ beweist eine bereits im Feldzentrum wirksame Hemmung. Diese Zentrum-Inhibition begrenzt die Erregungssummation im RFZ bei zunehmender Flächengröße des Lichtreizes. 4. On- und off-Zentrum-Neurone unterscheiden sich in beiden Adaptationszuständen in der Höhe des Entladungsniveaus. Die Entladungsraten der on-Zentrum-Neurone nach Licht-an übertreffen um ein Mehrfaches die Entladungsraten der off-Zentrum-Neurone nach Licht-aus. Die Unterschiede sind gruppenstatistisch hoch signifikant. Die interneuronale Variabilität der Entladungsraten ist bei den onZentrum Neuronen erheblich geringer als bei den off-Zentrum-Neuronen. 5. Dunkel -und Helladaptation führt zu signifikantem Unterschied der Entladungsraten: bei Helladaptation liegt die Impulsrate beider Neuronentypen höher als bei Dunkeladaptation und der Summationsbereich ist um 5–10% größer. 6. Für die mathematische Beschreibung der Summationsverläufe ist die Hyperbel besser geeignet als die logarithmische und Potenzfunktion. Logarithmus- und Potenzfunktionen beschreiben den konstanten asymptotischen Teil der Summationskurven ungenügend und eigenen sich nur für den Kurventeil im innersten Summationsbereich. Die Bedeutung der Befunde für eine dynamische Interpretation der visuellen Feldorganisation und mögliche Beziehungen zur lateralen Umfeldhemmung werden diskutiert.
    Notes: Summary 1. Spatial summation of suprathreshold light stimuli within receptive field centers (RFZ) of retinal ganglion cells was investigated during dark and light adaptation in cats. The mean discharge rates for 200 and 500 msec following light on or off were the computed response criteria. The summation effects were analyzed for single neurones and statistically for grouped neuron populations of the two neuronal subsystems B (on-center-neurones) and D (off-center-neurones). 2. Spatial summation is restricted to a small part of the RFZ. On-centerneurones increase their on-discharge rates with increasing spot sizes, only if the stimulus illuminates less than 1/5 of the RFZ. The summating area of the off-centerneurones is smaller (about 1/10 of the RFZ). 3. The limitation of spatial summation to a small part of the RFZ indicates the existance of inhibition within the RFZ. This center-inhibition sets a constant limit for excitation summation in the RFZ. 4. The mean neuronal response rates for the 2 subsystems show significant differences: The on-discharges of the on-center-neurones exceed the off-discharges of the off-center-neurones by a factor of 3–5. These highly significant differences occur at both adaptation levels and are not due to different spontaneous activity. Interneuronal response variability of the off-center-neurones was twice as large as that of the on-center-neurones. 5. Change from dark to light adaptation had only a small but significant influence on summation properties. The poststimulus discharge rates were higher during light adaptation and the summating area was slightly larger (about 5–10%). 6. A comparative curve fitting procedure for three suitable mathematical functions revealed that the hyperbola describes the neuronal summation curves better than a logarithmic or power function. The latter do not fit the constant asymptotic part of the curve. The significance of the results for a dynamic interpretation of the organisation of visual receptive fields is discussed.
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Experimental brain research 8 (1969), S. 219-231 
    ISSN: 1432-1106
    Keywords: Cerebral cortex in vitro ; Chloride transport ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The kinetics of the uptake of chloride by slices of cat cerebral cortex incubated in vitro have been studied for a wide range of concentrations of chloride and potassium in the incubation media. 1. In studies with 36Cl at a constant concentration of external K+, the rate of entry of chloride into slices of cat cerebral cortex (after equilibration with the fluid of the extracellular space) followed Michaelis-Menten kinetics with Vmax=7.7 μmoles/g/min and Km=245 mM. The kinetic data so described differ significantly from a curve describing simple diffusion (P 〈 0.02). 2. A clear dependence on concentration of K+ in the incubation medium was demonstrated. When external chloride was held constant at 6.8 mM and concentrations of potassium were varied over a range of 27–100 mM, the apparent rate of entry of chloride followed Michaelis-Menten kinetics with Vmax=0.191 μmoles/ g/min and Km=30.3 mM. 3. Under similar equilibrium conditions, the rate of influx of chloride was not statistically different from the rate of efflux, and the value for extracellular space (355 μl/g) derived by extrapolation from efflux data was of an identical order of magnitude to the value (352 μl/g) obtained from influx data. These values are essentially identical to those previously determined for chloride space of cat cerebral cortex in vivo (Bourke, Greenberg and Tower 1965). 4. The total, membrane-delimited content of chloride in cerebral cortex, as defined in these studies in vitro, was a function of the concentration of K+ in the incubation medium.
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Experimental brain research 8 (1969), S. 232-248 
    ISSN: 1432-1106
    Keywords: Cerebral cortex in vitro ; Edema ; Fluid compartmentation ; Chloride transport ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The ionic parameters of incubation media which foster both the development and subsequent reduction of swelling of slices of cerebral cortex under isosmotic conditions of incubation in vitro are described. A linear relationship between increasing chloride concentrations in incubation media and progressive swelling of tissue slices (under conditions of constant temperature and K+ concentrations and isotonicity of incubation media) is demonstrated. Subsequent reduction of chloride concentration in incubation media together with reciprocal replacement by isethionate is associated with significant and characteristic reduction in the volume of tissue swelling when all other conditions of incubation, including isotonicity of the media, are kept constant. The ionic composition of the fluid of swelling under different conditions of incubation is derived together with the ionic composition and expected transmembrane potentials of the neuronal compartment of cerebral cortex in vitro. Mechanisms involved in the development and subsequent reduction of swelling of cerebral cortex in vitro are discussed, and proposals for possible clinical applications are suggested.
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  • 8
    ISSN: 1432-1106
    Keywords: Lateral geniculate body ; Spatial summation ; Off-center-characteristics ; Geniculate transfer ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung 1. Die räumliche Summation im receptiven Feldzentrum von Neuronen des Corpus geniculatum laterale (CG-L) wird beschrieben und mit entsprechenden Untersuchungen an retinalen Ganglienzellen verglichen. Neben größerer interneuronaler Variabilität ergeben sich ausgeprägtere Unterschiede der Summationseigenschaften der on-und off-Zentrum-Neurone. Der effektive Summationsbereich von etwa 1/5 der Fläche des RFZ ist in Retina und CGL etwa gleich. 2. Die on-Zentrum-Neurone des CGL zeigen in beiden Adaptationszuständen einen ähnlichen Summationsverlauf wie in der Retina. Das Entladungsnieau ist im CGL jedoch erheblich geringer und nicht durch Unterschiede in der Spontanaktivität zu erklären. 3. Die Mehrzahl der off-Zentrum-Neurone des CGL zeigt bei DA inverse Summationsverläufe wie in der Retina: durchgehende Verminderung der Entladungsrate der off-Antworten bei Vergrößerung der Reizfläche im RFZ. Eine kleine Gruppe zeigt einen parabelförmigen Summationsverlauf mit Entladungszunahme bis zu Reizflächen von 10–30% der Fläche des RFZ und darauffolgender Entladungsminderung. Bei Helladaptation zeigen fast alle off-Zentrum-Neurone diesen Parabelverlauf. Das durchschnittliche Entladungsniveau ist von dem retinaler offZentrum-Neurone nicht signifikant verschieden. 4. Die interneuronale Variabilität der Summationsvorgänge im RFZ von CGLNeuronen ist gegenüber den retinalen Ganglienzellen deutlich größer. Dies gilt insbesondere für die off-Zentrum-Neurone. Das Summationsverhalten von CGLNeuronen läßt sich daher nicht wie in der Retina durch einen Funktionstyp beschreiben. 5. Die Befunde sprechen für eine Transformation des retinalen Eingangs der off-Zentrum-Neurone im CGL, während die on-Zentrum-Neurone außer der bekannten Frequenzuntersetzung keine wesentliche Umformung erkennen lassen.
    Notes: Summary 1. Spatial summation in the receptive field center of neurones of the lateral geniculate body (CGL) is limited by inhibition to a small part of field center. Variations of stimulus size are only effective if the stimulus is smaller than about 1/5 of the area of receptive field center. Thus, the active summating area of the field center in the CGL corresponds to that of the retina. Geniculate neurones, however, show less homogeneous responses and the summation properties of the two neuronal subsystems (on-center-and off-center-cells), show greater differences than in the retina. 2. The form of summation curves for the on-center-neurones of the CGL is similar to those of the retina at both adaptation levels. However, the average responses rates in the CGL are considerably lower. This is not due to differences of spontaneous activity. 3. The summation characteristics of off-responses of off-center-neurones of the CGL are quite different from those in the retina. In dark adaptation the majority of CGL neurones respond with decreasing discharge rates to increasing spot-sizes within the field center. A small number show an initial increase of discharge rates up to stimulus sizes of about 1/10 of the receptive field center before a decrease occurs. This parabolic summation type is typical for most off-center-neurones in light adaptation. The mean discharge levels are the same as those of the retinal offcenter-neurones. 4. The higher interneuronal variability of summation curves especially of the off-center-neurones of the CGL indicates a more complex determination of the discharge properties of CGL neurones. This functional differentiation of single neurones is congruent with the more complex structural and synaptic organisation in CGL. 5. With respect to spatial summation, the results indicate a transformation of the retinal input of the off-center-neurones at the geniculate level, whereas the oncenter-neurones are nearly unchanged.
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  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Experimental brain research 8 (1969), S. 79-96 
    ISSN: 1432-1106
    Keywords: Evoked potential thresholds ; Factor analysis ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Zur Beschreibung von Korrelationen zwischen zahlreichen elektrophysiologischen Daten aus verschiedenen Hirngebieten wurde eine Faktorenanalyse nach der Hauptachsenmethode gerechnet. Ausgangsmaterial dieser Analyse waren Schwellen subcortical ausgelöster und abgeleiteter Antwortpotentiale auf Einzelreize. Das resultierende Faktorenmuster ermöglicht ein quantitatives Konzept der Schwellendetermination subcorticaler Reizantworten und zugleich ein Modell von Funktionsbeziehungen zwischen einigen Hirnstrukturen. Die Reizungen und Ableitungen erfolgten bei 35 encéphale isolé-Katzen mit Hilfe bipolarer Elektroden in folgenden Arealen: Amygdala, Hippocampus, Septum, N. dorsomedialis Thalami, Hypothalamus posterior und Formatio reticularis mesencephali. Es wurden 435 Korrelationskoeffizienten zwischen den Schwellen von 30 subcorticalen Verbindungen gebildet und zum Zwecke einer Datenreduktion durch eine Matrix von 5 Faktoren reproduziert. 1. Jeder Faktor repräsentierte hohe Schwellenkorrelationen zwischen den efferenten Projektionen jeweils eines Kerngebietes. Demnach nimmt im allgemeinen die Aktivität des Reizortes den größten Einfluß auf die Schwelle eines Antwortpotentials. Diese Hypothese ist durch pharmakologische Untersuchungen belegt worden [27] 2. Kovariationen von Reizantworten mit identischen Ableiteorten ergaben sich ausnahmslos, wenn die Latenzzeiten mehr als 11 msec betrugen. 3. Zusätzlich zeigte die Faktorenmatrix Schwellenkorrelationen zwischen: a) den hypothalamischen Efferenzen und mehreren hippokampalen Afferenzen langer Latenz (positive Korrelationen) b) retikulo-limbischen Verbindungen und „primären” Efferenzen von Amygdala und Hippocampus (positive Korrelationen) c) Antwortpotentialen, die durch Reizung der Formatio reticularis, und solchen, die durch Reizung des N. Amygdalae ausgelöst waren (negative Korrelationen) d) den Efferenzen des N. dorsomedialis Thalami und limbischen Projektionen langer Latenz zur mesencephalen Formatio reticularis (positive Korrelationen) Die Interpretation dieser Zusammenhänge bestätigt und erweitert einige bekannte Modelle von Beziehungen zwischen subcorticalen Kerngebieten. Abschließend wird mit Rücksicht auf die Linearität der mathematischen Methode die Anwendbarkeit der Faktorenanalyse auf Schwellen von Reizantworten diskutiert.
    Notes: Summary In 35 cats (encéphale isolé) evoked responses were elicited and recorded with bipolar electrodes from the amygdala, hippocampus, septum, dorsomedial thalamic nucleus, posterior hypothalamus, and mesencephalic reticular formation. Correlations between the thresholds of responses in different areas following stimulation of other areas were described by a factor analysis according to the principal axis method. 435 coefficients of correlation were calculated and reproduced by a matrix of 5 factors for the purpose of data reduction. Each factor represented high threshold correlations between the efferent projections of one region, which suggests that the activity of the stimulated site exerts a major influence on the evoked potential threshold. This is supported by pharmacological studies [27, 49]. Covariations of responses recorded in the same nucleus were always found, if the latencies exceeded 11 msec. The factor matrix indicated threshold correlations between: the efferent projections of the hypothalamus and several long latency afferent projections to the hippocampus (positive correlations); reticulo-limbic connections and “primary” efferent connections of the amygdala and hippocampus (positive correlations); evoked potentials following reticular and amygdaloid stimulation (negative correlations); the efferent projections of the dorsomedial thalamic nucleus and long latency limbic projections to the mesencephalic reticular formation (positive correlations). The interpretation of these relationships confirms and extends some well known models of relations between subcortical regions. The applicability of factor analysis to evoked potential thresholds is discussed with regard to the linearity of the mathematical method.
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  • 10
    ISSN: 1432-1106
    Keywords: Muscle spindle ; Gamma motor control ; Mesencephalic reticular formation ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Effects of repetitive stimulation of the mesencephalic reticular formation (MRF) on the static discharge and dynamic sensitivity of muscle spindle primary endings (soleus muscle) were studied in cats anaesthetized with Halothane (Fluothane). By progressive increasing the depth of anaesthesia three different fusimotor effects could be observed: 1. A static effect; the static discharge of the primary endings was strongly increased; the response to phasic stretch was decreased or remained unaltered. 2. A dynamic effect; the dynamic sensitivity of the primary endings was powerfully increased while the rate of discharge under static conditions was only slightly augmented. 3. A depressant effect; the static discharge and the dynamic sensitivity of primary endings were decreased. Repeated stimulation elicited successive static and dynamic effects. No specific regions within the MRF could be related to a particular effect.
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  • 11
    Electronic Resource
    Electronic Resource
    Springer
    Experimental brain research 9 (1969), S. 96-115 
    ISSN: 1432-1106
    Keywords: Pyramidal tract ; Fusimotor Neurons ; Forelimb ; Extensor ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The effects of cortical stimulation upon dynamic and static sensitivities of the sensory endings in muscle spindles have been analyzed. 63 single afferent fibers from the muscle spindles of the forelimb extensors: M. flexor carpi radialis, M. flexor digitorum communis and M. palmaris longus were isolated in dorsal root filaments in 20 adult cats under chloralose-urethane anesthesia. They were identified by their response to stimulation of the median nerve. 1. Surface anodal repetitive stimulation of the anterior sigmoid gyrus was found to produce an enhancement of static response of single Group II fibers. Effective area was localized in a restricted region which corresponded to the forelimb motor area. The effect was obtained without any concomitant muscle contraction. Similarly, the stimulation increased the resting discharges of the Group Ia fibers from the same muscles. 2. Stimulation of the same area in the cerebral cortex was also found to increase the dynamic sensitivities of primary sensory endings. The increase was revealed by an enhancement of initial burst discharge during relaxation period of a twitch contraction caused by median nerve stimulation. 3. These results indicate that stimulation of the forelimb motor area has a facilitatory effect on both the static and dynamic fusimotor neurons innervating the muscle spindles of the test muscles. 4. The effects were reproduced in pyramidal tract preparations in which the brainstem was cut either at the level of the midbrain except for the cerebral peduncle or at the level of caudal medulla oblongata sparing the pyramid. 5. The threshold for the fusimotor effects was less than 1.3–1.5 times threshold of the pyramidal tract discharge, when the best spot for eliciting the fusimotor response was chosen. These results indicate that the effects of cortical stimulation are mainly mediated by the fast conducting pyramidal tract fibers.
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  • 12
    Electronic Resource
    Electronic Resource
    Springer
    Experimental brain research 9 (1969), S. 164-182 
    ISSN: 1432-1106
    Keywords: Emotional behaviour ; Hypothalamus ; Electricalstimulation ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. In order to compare the selective value of repetitive cathodal pulses of 8 c.p.s. and of continuous sine-wave alternating currents of 5000 c.p.s. (middle frequency current) when applied to brain tissue, explorations were made in the region of the hypothalamus that had yielded defence and/or flight reactions in earlier experiments. The region was explored by stimulating each point in turn with both current forms. At the same time measurement was made of the impedance of the brain tissue, and the effects produced by altering the time of rise of the middle frequency current on threshold of responses were also studied. The experiments were carried out on unanaesthetized, freely moving cats. 2. Both stimulation types produced affective (“emotional”) responses. The patterns elicited by low frequency cathodal pulse stimulation were often associated with stimulus-bound phasic muscle activity, i.e., flapping of ears, and twitching of whiskers, or, rotation of the head. Such extraneous motor effects were rarely obtained when continuous middle frequency currents were applied, and were tonic in character when present. 3. Mapping of reactive points revealed that the area producing defence or flight following middle frequency stimulation is smaller in size than the field delimited by means of repetitive cathodal pulse stimulation. These results strongly suggest that spread of current can be reduced by using middle frequency current stimulation. This apparently local (and hence highly selective) action is paralleled by a lower impedance of the brain tissue to the rapidly changing polarity of this current. 4. The hissing (and/or growling) associated with the defence pattern showed adaptation to suddenly rising middle frequency currents of 30 secs duration. An increase in threshold of hissing occurred when the time of rise of the current was prolonged. Flight, in contrast, was obtained at the same critical intensity regardless of the time of rise of current. 5. The nature of the stimulatory action of middle frequency current (examined in the peripheral nerve by Wyss) and the advantages presented by this new method of brain stimulation are briefly discussed.
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  • 13
    Electronic Resource
    Electronic Resource
    Springer
    Experimental brain research 9 (1969), S. 30-52 
    ISSN: 1432-1106
    Keywords: Climbing fibers ; Mossy fibers ; Vestibulo-cerebellar input ; Cat ; Frog ; Golgi cell inhibition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. Field and unitary potentials evoked in the vestibulo-cerebellum of frog and cat following vestibular nerve stimulation were recorded with microelectrodes and correlated with their site of origin in the various layers of the cerebellar cortex. 2. In the frog, primary vestibular fibers project both as mossy and as climbing fibers onto the cerebellar auricular lobe. Secondary vestibulo-cerebellar fibers seem to end exclusively as mossy fibers in the auriculum. As a consequence of this dual projection, extra- and intracellular recordings from Purkinje cells in the auricular lobe show two kinds of responses to vestibular nerve stimulation: a) graded, repetitive firing mediated through mossy fiber-granule cell-parallel fiber pathways, and b) all-or-none burst responses caused by monosynaptic impingement of vestibular climbing fibers on Purkinje cells. 3. The field and unitary potentials evoked in the cat nodulus, flocculus and uvula following vestibular nerve stimulation are shown to be generated by mossy fibers exclusively. Considerable convergence of the two labyrinthine mossy fiber inputs to a given cerebellar area was found. 4. Interaction of contralateral and ipsilateral mossy fiber input at the level of the flocculus suggests that Golgi cell inhibition might operate not only as a simple inhibitory feedback loop, but also as a complex gating operator at the granule layer. 5. No short latency climbing fiber activation of Purkinje cells was observed following VIIIth nerve stimulation. Stimulation of the contralateral inferior olive evoked short latency climbing fiber EPSPs in Purkinje cells of the vestibulo-cerebellum. Suggestions are made as to the possible role of mossy and climbing fiber inputs to this area of the cerebellum.
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  • 14
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    Experimental brain research 9 (1969), S. 284-306 
    ISSN: 1432-1106
    Keywords: Cutaneous receptive fields ; Spinal cord ; Cat ; Pain
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Examination of cutaneous receptive fields (RFs) of lamina 5 cells in the lumbar spinal cord of decerebrate cats shows them to have three distinct zones with respect to mechanical and electrical stimulation. The mean response rate to both mechanical and electrical stimulation in zone 1 increases steadily up to the highest strengths used; in zone 2, surrounding zone 1 mainly proximally, mild stimuli reduce the mean rate, stronger stimuli increase it; in zone 3, mainly proximal to zone 2, all stimuli reduce the rate. Temporally, zone 1, electric shocks near threshold produce bursts of firing followed by inhibition. With increased stimulus strength, the bursts lengthen to a second or more. In zones 2 and 3, inhibition at all strengths is preceded at higher strengths by bursts of firing. Cold-blocking the spinal cord at lower thoracic levels reversibly increases the ongoing activity of these cells, increases the area of zones 1 and 2, and almost completely suppresses all inhibition. Stimulation of dorsal columns and threshold stimulation of distant dorsal roots inhibits ongoing and induced activity. Barbiturate decreases ongoing activity and the duration of firing produced by cutaneous electrical stimulation but does not decrease inhibition. These results are consistent with a model in which low-threshold fibres are excitatory only over a small central area of the RF of a lamina 5 cell (zone 1), high threshold fibres are excitatory over a larger area (zones 1 and 2), and low threshold fibres are inhibitory over the entire receptive field (zones 1, 2 and 3) with a slower time-course. This inhibition is tonically enhanced by descending influences in the decerebrate cat. It is suggested that the high and low threshold fibres correspond approximately to the small and large diametre fibres whose balance is the basis for the coding of pain in the theory of melzack and wall.
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  • 15
    ISSN: 1432-1106
    Keywords: Muscle spindle ; Gamma motor control ; Reticular formations ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. During a progressive increase of Fluothane (Halothane) anaesthesia, repetitive stimulation of the mesencephalic retioular formation (MRF) produces several fusimotor effects — static, dynamic or depressant — on primary endings of soleus muscle spindles (Vedel et Mouillac-Baudevin 1969). 2. Transection of the brain immediately rostral to the site of stimulation may increase the dynamic effect but does not alter the static or the depressant effects. 3. A section of the rubrospinal tract does not modify the fusimotor effects elicited by stimulation of the MRF. 4. Transections of the spinal cord have shown that the pathways responsible for the transmission of these effects are mainly situated in the ipsilateral ventral and ventrolateral funiculi which contain the efferent fibers from the pontine reticular formation (PRF), from the bulbar reticular formation (BRF) and from the vestibular nucleus. 5. Contra and ipsilateral PRF stimulation produces the static fusimotor effect; contralateral stimulation from a small anterior region produces the dynamic effect. 6. Stimulation of the lateral part of the ipsilateral BRF elicits the dynamic effect while stimulation of the medial part elicits the static effect.
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  • 16
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    Naunyn-Schmiedeberg's archives of pharmacology 262 (1969), S. 73-86 
    ISSN: 1432-1912
    Keywords: Strophanthidine Derivatives ; Toxicity ; Absorption ; Guinea-Pig ; Cat ; Strophanthidinderivate ; Toxicität ; Resorption ; Meerschweinchen ; Katze
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Es wurde die Wirksamkeit verschiedener Ester und Äther von Helveticosid und Helveticosol bei i.v. und intraduodenaler Zufuhr an Katzen und Meerschweinchen geprüft. 1. Bei i.v. Dauerinfusion waren Helveticosol und seine Derivate bei Meerschweinchen etwa doppelt so wirksam wie die analogen Helveticosidverbindungen. Bei der Katze bestand kein Unterschied. Die Monomethyläther Cymarin und Cymarol waren gleich oder sogar stärker wirksam, alle übrigen Derivate deutlich schwächer als die Ausgangssubstanzen. 2. Die tödlichen Dosen bei intraduodenaler Injektion lagen beim Meerschweinchen für einige Substanzen in gleicher Größenordnung oder niedriger als die Titer bei i.v. Infusion. Diese hohe enterale Wirksamkeit kann bei Helveticosid und seinen Derivaten durch eine Reduktion zu dem wirksameren Helveticosol, bei Estern außerdem durch eine Hydrolyse zu wirksameren Glykosiden vorgetäuscht werden. 3. Bei intraduodenaler Infusion an Katzen waren alle geprüften Ester und Äther wirksamer als Helveticosid und Helveticosol. Die aus dem Verhältnis der toxischen Dosen bei i.v. und intraduodenaler Infusion berechnete enterale Wirksamkeit lag zwischen 20 und 50%. 4. Unterschiede in der Dauer der intraduodenalen Infusion bei Katzen lassen sich berücksichtigen, wenn man von der theoretischen Annahme einer exponentiellen und vollständigen Resorption ausgeht und die Halbwertszeit für die Resorption berechnet. Die minimale Resorptionsgeschwindigkeit lag bei einigen Derivaten in gleicher Größenordnung wie bei Digoxin und Digitoxin. Es wird auf den Unterschied zwischen der auf Grund der pharmakologischen Wirkung bestimmten relativen enteralen Wirksamkeit und der Resorptionsquote hingewiesen. Letztere ist für die Verläßlichkeit der therapeutischen Wirkung eines Glykosids bei oraler Gabe maßgebend.
    Notes: Summary The efficacy of several esters and ethers of Helveticosid and Helveticosol was assayed by intravenous and intraduodenal administration to cats and guinea-pigs. 1. In guinea-pigs, Helveticosol and its derivatives were approximately twice as active on intravenous infusion as the analogous derivatives of Helveticosid; in cats there was no significant difference. The monomethylethers Cymarin and Cymarol were equally or slightly more potent, all other derivatives were weaker than the original compound. 2. In guinea-pigs the lethal doses of some compounds on intraduodenal injection were equal to or even lower than those on intravenous infusion. This may partly be accounted for by a reduction of Helveticosid and its derivatives to the more potent Helveticosol analogues, partly by a hydrolysis of the esters, yielding compounds of higher activity. 3. On intraduodenal infusion in cats, all the investigated esters and ethers were more active than Helveticosid and Helveticosol. The relative enteral activity calculated from the ratio of the toxic doses on intravenous and intraduodenal infusion varied between 20 and 50%. 4. Due to a delayed absorption from the gastrointestinal tract, the toxic dose falls with a reduced speed of intraduodenal infusion. Assuming an exponential and complete absorption, the half time of absorption was calculated. For some of the compounds investigated, the speed of absorption was comparable to that of Digoxin and Digitoxin. The difference between the relative enteral activities determined by comparing equiactive doses on enteral and parenteral administration and the percentages of the glycosides which are absorbed from the gastrointestinal tract is pointed out. The latter is of prime importance for obtaining reproducible effects after enteral administration.
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  • 17
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    Naunyn-Schmiedeberg's archives of pharmacology 264 (1969), S. 406-419 
    ISSN: 1432-1912
    Keywords: Intestinal Absorption ; Cardiac Glycosides ; Blood of Portal Vein ; Intestinal Lymph ; Cat ; Intestinale Resorption ; Herzglykoside ; Portalvenenblut ; Darmlymphe ; Katze
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. The cardiac glyoosides digitoxin, ouabain, digoxin and peruvosid labelled with3H were injected into tied intestinal loops of anaesthetized cats in situ. The absorbed glycosides were measured in the blood of the portal vein and in the intestinal lymph. At the same time the3H-activity was measured in the blood of the peripheral circulation, in the bile and in the urine. 2. Calculation of the amount of glycosides totally absorbed from the3H-concentration in the blood of the portal vein and the circulation volume (bubble-flow-meter) gave the following absorption rates as a percentage of the administered dose per hour: digitoxin 56%, digoxin 42%, peruvosid 26% and ouabain 10%. 3. The amount of glycosides passing into the lymph during 1 hour was found to be only 0.006 to 0.02% of the amount offered. In lymph3H-activity cannot be measured earlier than 5 min after the administration of the labelled glycosides. The3H-concentration in the lymph did not equal that measured in the blood of the peripheral circulation until at least 1 hour after the administration and always remained below the3H-concentration of the blood in the portal vein. This proportion remained unchanged even if digitoxin was administered as an emulsion in oil instead of an aqueous solution. From the time course of3H-concentration it might be concluded that the glycosides do not pass directly to the lymph after absorption but indirectly by way of the blood. 4. The amount of glycoside excreted in the bile is for peruvosid 15,5% of the amount absorbed, for ouabain 1,9%, for digoxin 1,4% and for digitoxin 0,8%. The3H-activity excreted in urine is very small and can be disregarded. 5. Chromatographic analyses of the bile revealed, that in the case of digoxin, 4/5 of the amount excreted were unchanged, in the case of digitoxin and ouabain 2/3 and in the case of peruvosid only 1/4. In the lumen of the tied intestinal loops and in the tissue of the small intestine the glycosides were hardly metabolised.
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  • 18
    ISSN: 1432-2013
    Keywords: Cat ; Decerebration ; Afferents to Respiratory Centers ; Medulla Oblongata ; Reticular Formation ; Katze ; Decerebrierung ; Afferenzen zu Atemzentren ; Medulla oblongata ; Formatio reticularis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung An 11 intercolliculär decerebrierten Katzen wurde geziegt, daß Kälteblockade eines eng umschriebenen Feldes auf der ventralen Oberfläche der Medulla oblongata, wie früher für anaesthesierte Tiere beschrieben, zu Atemstillstand führt, wenn die kontralaterale Stelle auf der Medulla oblongata, die Sinusnerven und die Vagi ausgeschaltet sind. Zu Atemstillstand kam es auch, wenn statt der Kälteblockade 2% Novocain durch lokale Superfusion bei gleichzeitiger Gegenspülung der Umgebung mit künstlichem Liquor angewandt wurde, oder wenn ein mit 1% Novocain getränkter Tupfer lokal aufgelegt wurde. Außerdem führte Kälteblockade zu Atemstillstand, wenn durch kontinuierliche auch während der Kälteblockade anhaltende elektrische Reizung eines N. femoralis oder hinterer Lumbalwurzeln an decerebrierten Katzen oder des Hypothalamus an einer anaesthesierten Katze Steigerungen der Ventilation ausgelöst worden waren. Elektrische Reizung eines Sinusnerven führte zu Atemsteigerungen. Bei Sinusnervenreizung während eines durch Kälteblockade ausgelösten Atemstillstands kam es zu rhythmischer Atmung. Aus diesen Untersuchungen wird geschlossen, daß mit der Ausschaltung der beschriebenen Felder auf der ventralen Oberfläche der Medulla oblongata am sonst desafferentierten Tier die Gesamtheit der für die zentrale CO2-Empfindlichkeit verantwortlichen Strukturen erfaßt ist, daß nach Ausschaltung der zentralen und der peripheren Chemosensibilität eine unspezifische Aktivierung der Atmungszentren unwirksam ist und daß die Atmungszentren zur Ausbildung einer rhythmischen Atmung von spezifischen Antrieben abhängig sind.
    Notes: Summary It was shown in 11 decerebrated cats, that cooling of a small and well defined area on the ventral surface of the medulla will cause respiratory arrest if the contralateral area of the medulla, the vagi and sinus nerves are eliminated. This confirms earlier observations obtained in anesthetized cats. Apnea was also produced by local superfusion of 2% procain with simultaneous flushing of the immediate surrounding area with mock spinal fluid. Local application of a small sponge soaked with 1% procain had the same effect. Electrical stimulation of femoral nerves or posterior roots which results in hyperventilation on the decerebrated cat failed to show any effect during periods of cold blockade. There was no respiratory response to direct stimulation of the hypothalamus in an anesthetized cat during cooling. Electrical stimulation of one sinus nerve caused an increase of ventilation. Sinus nerve stimulation during apnea induced by cold blockade resulted in rhythmical respiration. It is concluded from these experiments: Blocking of the area under discussion on the ventral surface of the medulla, inhibits all structures responsible for the central CO2-sensitivity in the deafferentiated animal. There was no response to non-specific stimuli of the respiratory center after elimination of central and peripheral chemosensitivity. The respiratory centers apparently depend on specific stimuli to support rhythmical respiration.
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  • 19
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    Pflügers Archiv 309 (1969), S. 285-309 
    ISSN: 1432-2013
    Keywords: Labyrinthine Stimulation ; Types of Abducens Neurones ; Frequency Analysis ; Cat ; Labyrinthreizung ; Abducensneurone ; Frequenzanalyse ; Katze
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Single cell activity was recorded extracellularly from neurones in cat's abducens nuclei in unanesthetized, decerebrate preparations. Two types of neurones were found. i) The motoneurones (type IIA) increased their firing linearly or exponentially to contralateral constant angular accelerations and decreased firing to ipsilateral rotation. The increased frequency was maintained at a constant level without any sign of adaptation. This constant level of maximum frequency was proportional to the logarithm of the acceleration applied. No significant differences of the frequency responses of tonic and silent motoneurones were found. The conduction velocities of the axons of spontaneously firing type IIA cells were slower than in silent neurones. Electrical stimulation of the contralateral VIIIth nerve led to activation of the type IIA cells; stimulation of the ipsilateral nerve resulted in inhibition of both spontaneous discharge and antidromic invasion of the motoneurones. ii) The type IA units increased their firing rate to ipsilateral rotation and ceased to discharge in response to contralateral rotation. They never were excited antidromically by stimulation of the VIth nerve. However, they were excited by stimulation of the ipsilateral VIIIth nerve. Their possible functional role in the vestibulo-ocular system was discussed.
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  • 20
    ISSN: 1432-1106
    Keywords: Lateral cervical nucleus ; Midbrain lesions ; Nauta method ; Ultrastructural investigation ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The lateral cervical nucleus (LCN) has been studied with the light and electron microscope after midbrain lesions in kittens of different ages, and in adult cats. It has been shown that nerve cells remain within the contralateral LCN after hemisection of the midbrain. performed on 1 day old kittens. The estimated number of these remaining cells was 3–19% in the different cases. No fibers descending to the LCN from levels rostral to the midbrain could be demonstrated in adult cats with the Nauta technique. A combined Nauta and electron microscopical investigation was performed on kittens operated on at different ages and allowed to survive varying times postoperatively. At the operations the LCN-axons were transected at midbrain level. The Nauta investigation demonstrated silver impregnation of degenerating LCN-neurons on the affected side of the same type as has been described recently in other neuronal systems following axonal transection. The ultrastructural study revealed electron dense degenerating dendrites and probably also nerve cells within the LCN. The dense degenerative changes were very similar to the dense degeneration in terminal boutons following transection of parent axons. The potential value of the findings for electron microscopical research in neuroanatomy is discussed. The results in terms of connections of the LCN are discussed in the light of known anatomical and physiological data of the LCN.
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  • 21
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    Experimental brain research 7 (1969), S. 68-83 
    ISSN: 1432-1106
    Keywords: Medial geniculate body ; Inhibition ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. Inhibitory activity in the cat medial geniculate body (MG) was examined by stimulating electrically and acoustically the input and output of the MG. 2. A longer and more profound depression of excitability occurs following a click-evoked potential in the MG than in the inferior colliculus (IC) in both anesthetized and unanesthetized states. Recovery is cyclic in the barbiturate MG preparation. 3. Electrical stimulation of the brachium of the inferior colliculus (BIG) evokes a field potential in the MG consisting of clearly distinguishable presynaptic and postsynaptic components. The presynaptic component recovers rapidly, while the postsynaptic component requires 100–200 msec for full recovery. This depression of excitability is localized within the MG since cortical ablation does not alter its occurrence. 4. Stimulation of the BIC mimics the effects of click stimulation on single units. Excitatory, inhibitory and reverberatory responses are evoked by the BIC shock. Suppression of single unit activity correlates with the depression of excitability following a BIC-evoked field response. 5. Cortical stimulation can evoke antidromic and trans-synaptic unit responses in the MG, as well as causing a variety of inhibitory effects and reverberation. In view of the fact that cortical ablation does not impair the recording of these responses to afferent stimuli, it is suggested that the cortical-evoked responses are at least partly mediated by antidromic conduction to MG. 6. Evidence is presented that inhibitory effects of both afferent and cortical stimulation are due to active inhibition of MG unit activity. Speculations are made as to the mechanisms producing inhibition and reverberation in the MG.
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  • 22
    ISSN: 1432-1106
    Keywords: Electron microscopy ; Pontine nuclei ; Experimental neuroanatomy ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The electron microscopical changes occurring in the pontine nuclei following unilateral lesions of the primary sensorimotor cortex have been studied in 7 cats with a survival time from 2–23 days. A description is also given of the fine structure of the pontine regions in receipt of the fibres. These regions are shown in Fig. 1. The study shows that the boutons are practically only in synaptic contact with dendrites. The bouton density on these is only 16%. The boutons are of the en passage and terminal type, with the latter as the most common (Figs. 4a-e). The synaptic vesicles are rounded or elongated. The formaldehyde fixed material had 17.8% boutons with vesicles of the elongated type; the material fixed with a mixture of formaldehyde and glutaraldehyde had only 11.5% of such boutons. The degenerating boutons show the dark type of reaction and the majority of the corticopontine fibres are of the type shown in Figs. 4d and 4e. Astrocytes and microglial cells participate in the removal of degenerating boutons and terminal fibres. Degenerating boutons are present even at the 23 day stage and some have apparently only started to degenerate.
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  • 23
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    Experimental brain research 7 (1969), S. 32-50 
    ISSN: 1432-1106
    Keywords: Lateral cervical nucleus ; Spinal lesions ; Ultrastructural investigation ; Degenerating boutons ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The ultrastructure of terminal degeneration within the lateral cervical nucleus (LCN) after transection of its spinal afferent fibers 2 days–2 years earlier is described. The degeneration after 2 days was of both the neurofilamentous and dense type. The highest number of degenerating terminals, about 15%, was found after 4–5 days. Then most of the degenerating boutons were of the dense type. The degenerating terminals had synaptic contact with cell bodies and dendrites of LCN-neurons. Removal of the degenerating boutons seemed to be effected by a phagocytic cell present in increased number compared to the normal LCN. In cases with long survival times an increase in the number of astroglial filaments was observed. In an animal where the spinal afferents to the LCN had been cut 2 years earlier a decrease in medium size of the neurons was observed. The amount of dendritic spines was also considerably smaller than normally.
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  • 24
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    Experimental brain research 7 (1969), S. 143-157 
    ISSN: 1432-1106
    Keywords: Reticular formation ; Convergence ; Inhibition ; Cat ; Chloralose
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung 1. Ein konditionierender corticaler Reiz inhibiert den somatischen Startlereflex bei Katzen unter Chloralosenarkose für eine Dauer von mehr als 200 ms. Die Interaktionen zwischen beiden Reizen laufen in der bulbären und pontinen Formatio reticularis ab. 2. Dem Startlereflex liegt eine polysynaptische Erregungsschleife zugrunde, die die bulbäre und pontine Formatio reticularis durchzieht. Die Resistenz der reticulären Neurone gegenüber repetitiver Stimulation wurde als Kriterium ihrer funktionellen Lokalisation auf dem polysynaptischen Reflexbogen gewertet. 3. Die corticale Inhibition wird im Verlaufe der polysynaptischen Erregungsschleife zunehmend stärker. Neurone, die von den Startlereflexafferenzen direkt erregt werden, werden durch den corticalen Reiz nicht inhibiert. Dies schliebt eine präsynaptische Inhibition der reticulopetalen Fasersysteme aus.
    Notes: Summary 1. The startle reflex evoked by cutaneous stimulation in cats under chloralose anesthesia is inhibited for more than 200 ms by a conditioning cortical volley. The interaction between the cutaneous and the cortical volley takes place in the bulbar and pontine reticular formation. 2. The startle reflex involves a series of reticular neurones. Resistance to repetitive stimulation has been determined to evaluate the functional localization of each neurone within this polysynaptic path. 3. Inhibition following the cortical volley becomes increasingly more effective along the course of the polysynaptic path and is completed within 5–6 ms. Reticular neurones excited directly by the spino-reticular afferents are not inhibited, thus excluding a presynaptic inhibition of the spinoreticular fibres.
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  • 25
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    Experimental brain research 7 (1969), S. 195-213 
    ISSN: 1432-1106
    Keywords: Corpus callosum ; EEG synchronization ; Homolateral sensory evoked potentials ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Spontaneous EEG-patterns and evoked potentials (EP's) of symmetrical cortical areas were recorded in chronic and acute cats before and after section of the corpus callosum, the commissura anterior and posterior and the massa intermedia. The spontaneous EEG was recorded without and with anesthesia, EP's after electrical stimulation of the fore-paws only during nembutal anesthesia. — No changes in the bilateral coordination of spontaneous and evoked EEG-patterns could be seen after commissurotomy (CT). The bilateral coherence of EEG-waves as revealed by cross-correlation is low already in the normal cats and does not change significantly after CT. The values of cross-correlation coefficients at T = ± 15 msec vary during one EEG-record between -0.25 and +0.25 in the somatosensory, suprasylvian and temporal areas (mean values slightly above 0). In the visual area occasionally positive values between 0.5 and 0.8 were seen, but also here a large variation was found in all animals and the mean values were below 0.1. No consistent phase shift between both sides was observed. EEG-patterns like spindles or arousal, still occurred together in both hemispheres after CT, the variability of their exact beginning or end was the same as in controls. Spontaneous spindles often lasted longer after section of the massa intermedia. Homolateral EP's in the somato-sensory area were still present after CT. Rhythmical afterdischarges could be restricted to the contralateral somato-sensory cortex even before CT.
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  • 26
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    Psychopharmacology 14 (1969), S. 164-166 
    ISSN: 1432-2072
    Keywords: Benperidolum ; Cat ; Extrapyramidal Side Effect ; EEG ; Toxicity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Daily doses of 1–10 mg Benperidol were given perorally to cats during 26 months. The general behaviour and the EEG were unchanged during the treatment, in particular no signs of dyskinesia were observed. After discontinuation of the administration, the behaviour and the EEG of the animals stayed normal. Thus no lasting and irreversible side effects could be observed.
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  • 27
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    Psychopharmacology 15 (1969), S. 382-391 
    ISSN: 1432-2072
    Keywords: LSD ; Retina ; LGN ; Single Unit Activity ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The effect of LSD 25 (i. v. injection) on the spontaneous and evoked activity of the visual system was investigated in cats. 50 γ/kg did not change significantly the ERG and the visual cortical evoked potential. The spontaneous discharge rate of 14 out of 21 retinal ganglion cells showed an increase which reached its maximum within 20–30 min and which could still be present 1 hour following the injection. One third of the retinal units showed a slight depression of their spontaneous dischaRge rate with about the same time course. Single units of the LGN showed about the same behaviour. The response to light stimulation was slightly increased in some units and light induced inhibition was slightly shortened. The possible mechanism of the LSD-effect on retinal ganglion cell activity is discussed.
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  • 28
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    Cell & tissue research 101 (1969), S. 607-620 
    ISSN: 1432-0878
    Keywords: Glandula bulbourethralis ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Das Parenchym der Glandula bulbourethralis der Katze besteht aus weitlumigen, gebuchteten intraglandulären Gängen, in welche kurze, englumige, zumeist unverzweigte Tubuli einmünden. Der Drüse fehlt eine äußere Organkapsel, so daß ihre peripheren Tubuli stellenweise direkt zwischen den Fasern des quergestreiften M. bulboglandularis liegen. Die Drüsentubuli und die Buchten der intraglandulären Gänge sind mit einem einschichtigen Zylinderepithel ausgekleidet, auf den Gangfalten ist das Epithel abschnittsweise mehrreihig, Die sezernierende Epitheloberfläche ist durch die Ausbildung von interzellulären Sekretkapillaren vergrößert. Breite Zwischenzellspalten (Durchmesser etwa 1,5μ), in welche schlanke interdigitierende Cytoplasmafortsätze hineinragen, erstrecken sich von der Basalmembran bis kurz unter das Tubulusbzw. Ganglumen. Die lumenseitigen Zellgrenzen tragen einige stummelförmige Mikrovilli und besitzen zerklüftete Außenkonturen, die durch glykogenreiche Cytoplasmaprojektionen bedingt sind. Alle Epithelzellen sind reich an Mitochondrien. Die supranuklearen Abschnitte der meisten Gang- und Tubuluszellen enthalten Sekretgranula, welche im Elektronenmikroskop unterschiedliche optische Dichten aufweisen können. Die Granula enthalten ein PAS-positives, neuraminsäurehaltiges epitheliales Muzin, das in einzelnen Sekretkörnchen auch eine histochemische Reaktion auf Sulfatgruppen gibt. Alle Epithelzellen reagieren sehr stark auf unspezifische Esterase und stark auf β-D-Glucuronidase, β-D-Glactosidase sowie die Enzyme des Citronensäurezyklus, der Glykolyse und der Atmungskette (NAD-ICDH, SDH, ALD, LDH, ADH, GDH, NADH-T-Red, Cyt-Ox).
    Notes: Summary The bulbourethral glands of sexually mature male cats are studied with the light and electron microscope. The parenchyma consists of spacious, sinus-like intraglandular ducts and short, narrow, mostly unbranched tubular endpieces. The gland has no complete connective tissue capsule, consequently some of the peripheral tubules are situated directly in between the fibers of the surrounding bulboglandularis muscle. The endpieces and the sinus of the intraglandular ducts are lined by a simple columnar epithelium, whereas the folds of the ducts are generally covered by a low pseudostratified epithelium. The secretory surface of the cells is increased by intercellular canaliculi which communicate with the gland lumen. These canaliculi are identified on the light microscopic level by their strong 5′-nucleotidase activity. Furthermore widened intercellular spaces (approximately 1,5 μ in diameter) filled with slender, interdigitating cytoplasmic processes extend from the basal lamina to the apical junctional complexes. The luminal cell pole exhibits some short microvilli and forms irregularly shaped, glycogen containing protrusions. Within the cytoplasm of the gland cells numerous spherical mitochondria, some dense bodies, a typical Golgi apparatus, free ribosomes and a poorly developed endoplasmic reticulum are to be observed. Secretory granules which can be grouped into three types on the basis of their electron density occur in the supranuclear regions of most of the cells. According to histochemical tests all granules contain a periodate reactive sialomucin and some of them also sulfate groups. The glandular parenchyma is site of an exceptionally strong unspecific esterase activity and is rich in β-D-glucuronidase, β-D-glactosidase, aldolase, α-glycerophosphate dehydrogenase, lactate dehydrogenase, alcohol dehydrogenase, NAD-dependent isocitrate dehydrogenase, succinate dehydrogenase and cytochrome oxydase.
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  • 29
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    Weinheim : Wiley-Blackwell
    Liebigs Annalen 727 (1969), S. 219-221 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions with Diazocarbonyl Compounds, XXXI V I ). o-Quinone Diazides and o-Quinones as Dehydrobenzene InterceptorsSuitably substituted o-quinone diazides can be used to intercept arynes with simultaneous N2-elimination and formation of dibenzofuranes. o-Quinones add arynes in a Diels-Alder synthesis to form cyclic diketo compounds, which react with o-phenylenediamine to give the corresponding quinoxalines.
    Notes: Arine lassen sich mit geeignet substituierten o-Chinondiaziden unter N2-Abspaltung und Bildung von Dibenzofuranen abfangen. o-Chinone addieren nach Diels-Alder Arine zu cyclischen Diketo-Verbindungen, die mit o-Phenylendiamin zu den entsprechenden Chinoxalinen kondensieren.
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  • 30
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    Weinheim : Wiley-Blackwell
    Liebigs Annalen 729 (1969), S. 231-233 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Oxidative Degradation of 5,6-DimethylbenzimidazolePrior to carrying out tracer experiments used in the investigation of the biosynthesis of 5,6-dimethylbenzimidazole (1) methods for its degradation had to be worked out. In order to identify all C-atoms, 1 had to be degraded by two procedures: The Kuhn-Roth degradation yields acetic acid and CO2. The acetic acid undergoes Schmidt degradation thus allowing the identification of C-5, C-6, and the methyl groups of 1. - The oxidation of 1 with K2Cr2O7 yields imidazole-4,5-dicarboxylic acid (4) which after decarboxylation gives imidazole and CO2. Thus C-2, C-8, and C-9 on the one hand and C-4 and C-7 on the other hand can be identified.
    Notes: Für Tracerversuche zur Biosynthese von 5.6-Dimethyl-benzimidazol (1) wurde 1 oxydativ abgebaut. Die Identifizierung sämtlicher C-Atome gelingt nur durch Abbau nach zwei Methoden: Der Kuhn-Roth-Abbau führt zu Essigsäure und CO2. Durch anschließenden Schmidt-Abbau der Essigsäure können C-5, C-6 und die Methyl-Gruppen von 1 identifiziert werden. - Die Oxydation mit Kaliumdichromat führt zu Imidazol-dicarbonsäure-(4.5) (4), deren Decarboxylierung zu Imidazol und CO2 die Identifizierung von C-2, C-8 und C-9 bzw. C-4 und C-7 erlaubt.
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  • 31
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    Weinheim : Wiley-Blackwell
    Liebigs Annalen 728 (1969), S. 49-55 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Molecular Structure Changes in Chemical Reactions, XXI 1 ). Deamination in the Bicyclo[2.2.l]-heptane SeriesThe deamination of bornyl- and fenchylamines is studied by gas chromatography. In contrast to norbornylamines the exo and endo compounds behave differently. A Wagner-Meerwein rearrangement is the main reaction in both cases. The resulting tertiary alcohol in the fenchane series is stereochemically mixed. Ring opening is considerable with endo amines but only slight with exo amines. The results are compared with those of the solvolysis in methanol of the corresponding tosylates.
    Notes: Die Desaminierung der Bornyl- und Fenchylamine wird gaschromatographisch untersucht; die im Gegensatz zu den Norbornylaminen bestehenden Verschiedenheiten von exo- und endo- Form werden festgelegt. Die Hauptreaktion ist allerdings in beiden Fällen eine Wagner-Meerwein-Umlagerung. Der entstehende tertiäre Alkohol in der Fenchan-Reihe ist sterisch nicht einheitlich. Eine Ringspaltung tritt bei den endo-Aminen erheblich, bei den exo-Aminen minimal ein. Die Ergebnisse werden mit denen der Methanolyse der entsprechenden Tosylate verglichen.
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  • 32
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    Weinheim : Wiley-Blackwell
    Liebigs Annalen 729 (1969), S. 119-123 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Azobarbituric Acid arid Alloxan AzineAzobarbituric acid (2) is formed as a by-product of the reaction between barbituric acid and carbamoylazide (H2NCON3), the main product being 5-aminocarbonylbarbituric acid. It is easily dehydrogenated by bromine water to give alloxan azine (3) which readily undergoes disproportionation yielding 2, diazobarbituric acid (1), and alloxan (5). 2 can be prepared in good yield by coupling diazobarbituric acid with barbituric acid in alkaline medium.
    Notes: Azobarbitursäure (2) tritt als Nebenprodukt der Reaktion zwischen Barbitursäure und Carbamoylazid (H2NCON3) zu 5-Aminocarbonyl-barbitursäure auf. 2 wird durch Bromwasser zu Aloxanazin (3) oxydiert, das leicht disproportioniert, wobei 2, Diazobarbitursäure (1) und Alloxan (5) entstehen. 2 wird in guter Ausbeute durch Kupplung von Diazobarbitursäure mit Barbitursäure in alkalischem Medium dargestellt.
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  • 33
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    Weinheim : Wiley-Blackwell
    Liebigs Annalen 729 (1969), S. 139-145 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cyanacetaldehyde Derivatives and Reaction ProductsThe reaction of malondialdehydedioxim (2) with aromatic diazonium salts or nitrous acid leads to derivatives 5 of cyanoacetaldehyde in a quite simple way. The hydrazones of these compounds can be converted into 1-substituted 5-aminopyrazoles 6.
    Notes: Ausgehend vom Malondialdehyddioxim (2) erschließt sich über die Umsetzung mit Aryldiazoniumsalzen oder salpetriger Säure ein einfacher Zugang zu Cyanacetaldehyd-Derivaten 5, von denen sich die Hydrazone in 1-substituierte 5-Amino-pyrazole 6 überführen lassen.
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  • 34
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    Weinheim : Wiley-Blackwell
    Liebigs Annalen 729 (1969), S. 124-138 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Triazolylbenzoic Acids and Acylaminoquinazolones from Benzoxazinones and Curbohydrazideso(4-s-Triazolyl)benzoic acids 2 can easily be prepared in good yields from so-called acylanthranils with carbohydrazides in boiling ethanol. In hot benzene, the isomeric 3-acyl-amino-4-quinazolones 1 are formed from the same components. Both reactions proceed via amidrazones 11, which are formed by the reaction of the terminal hydrazide nitrogen atom with the oxazinone nucleus at C-2. - 3,4,5-Trisubstituted s-triazoles can also be made from N-substituted imidoyl chlorides with hydrazides. - s-Triazolo[4,3-a]quinolines of the type 18c are available by intramolecular condensation of certain triazolylbenzoic acids.
    Notes: o-[s-Triazolyl-(4)]-benzoesäuren 2 können präparativ einfach aus [Acylanthranilen] und Carbonsäurehydraziden in siedendem absolutem äthanol gewonnen werden. Aus den gleichen Komponenten bilden sich in Benzol die isomeren 3-Acylamino-chinazolone-(4) 1. Beide Reaktionen verlaufen über Amidrazone 11, gebildet bei der Reaktion des endständigen Hydrazid-Stickstoffs mit dem Kohlenstoff-Atom 2 des Oxazinon-Ringes. - Eine weitere Synthese für den 3.4.5-trisubstituierten s-Triazol-Ring ist mit N-substituierten Imidchloriden 7 und Hydraziden ausführbar. Bestimmte Triazolylbenzosäuren lassen sich zu s-Triazolo[4.3-a]chinolinen vom Typ 18c kondensieren.
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  • 35
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    Liebigs Annalen 729 (1969), S. 198-204 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Frog Venoms.Isolation and Structure of Pumiliotoxin CPumiliotoxin C, a base of the composition C13H25N, is isolated as the crystalline hydrochloride from the skin extracts of Dendrobates pumilio, a strikingly colored Panamanian frog. Complete X-ray analysis of this new venom by the so-called symbolic addition procedure establishes the structure as 2-n-propyl-5-methyl-cis-decahydroquinoline, a type of base, though related to coniine, is here reported for the first time as a natural product. The relative configurations of the four asymmetric centers are elucidated. In addition to this venom there are the congeners pumiliotoxins A and B, as well as further homologs and analogs which have also been isolated from the related frog Dendrobates auratus, and characterized by mass spectra.
    Notes: Aus dem Hautextrakt des in Panama vorkommenden, auffallend gefärbten Froschs Dendrobates pumilio läβt sich das gut kristallisierende Hydrochlorid einer Base Pumiliotoxin C der Formel C13H25N isolieren. Durch Röntgen-Strukturanalyse dieser Base nach dem „symbolischen Additionsverfahren“ (symbolic addition procedure) läβt sich zeigen, daβ es sich um einen zum ersten Mal in der Natur beobachteten, dem Coniin weitläufig verwandten Giftstofftyp handelt, nämlich um ein 2-n-Propyl-5-methyl-cis-decahydrochinolin, dessen vier asymmetrische Zentren in ihrer relativen stereochemischen Bezeichnung aufgeklärt werden. Neben Pumiliotoxin C leiten sich auf Grund der Massenspektren die Pumiliotoxine A und B sowie noch weitere aus dem verwandten Frosch Dendrobates auratus isolierte Basen von einem ähnlichen cis-Deca- oder Octahydrochinolin-System ab.
    Additional Material: 5 Ill.
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  • 36
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Constituents of the Horse Chestnut, VII 1). O-Isopropylidene Derivatives of Protoescigenin, Barringtogenol C,and their 21-Angelic (Tiglic) Acid and 28-Angelic (Tiglic) Acid EstersThe O-isopropylidene derivatives of protoescigenin barringtogenol C, and their 21-angelic (tiglic) acid and 28-angelic(tiglic) acid esters have been prepared by reaction with acetone/p-toluenesulfonic acid. The substances were isolated by column chromatography and their structures have been determined.
    Notes: O-Isopropyliden-Derivate von Protoäscigenin, Barringtogenol C und von deren 21- bzw. 28-Angelika(Tiglin)säureestern werden durch Umsetzung mit Aceton/p-Toluolsulfonsäure hergestellt, durch Säulenchromatographie isoliert und in ihrer Struktur bestimmt.
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  • 37
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    Liebigs Annalen 729 (1969), S. 237-239 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Syntheses and Properties of Dithioamino Acid EstersFrom the previously unknown class of dithioamino acid esters three members have been synthesized: N-benzoyl dithioglycine ethyl ester, ∊-amino-dithiocaproic acid ethyl ester p-toluenesulfonate, and N-acetyl dithiophenylalanine ethyl ester. The syntheses have been carried out via the nitriles. The absorption bands of the C=S-group are at approximately 3100 Å and approximately 4500 Å (table 1). The proton magnetic resonance spectrum of the prototypic N-benzoyl dithioglycine ethyl ester (page 238) is consistent with its proposed structure.
    Notes: Aus der bisher unbekannten Gruppe der Dithioaminosäureester werden drei Vertreter dargestellt: N-Benzoyl-dithioglycinäthylester, ∊-Aminodithiocapronsäureäthylester-p-toluolsulfonat und N-Acetyl-dithiophenylalaninäthylester. Die Darstellung erfolgt über die Nitrile. Die Absorptionsbanden der C=S-Gruppe liegen bei ca. 3100 Å und ca. 4500 Å (Tab. 1). Das Protonenresonanzspektrum von N-Benzoyl-dithioglycinäthylester (S. 238) entspricht seiner Struktur.
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  • 38
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    Liebigs Annalen 725 (1969), S. 238-240 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: 3H-DesmethylphalloinA radioactive desmethylphalloin (2) is obtained by reduction of the CO-group of ketophalloidin (1) with 3H-containing NaBH4. It has almost the same toxicity as phalloidin (LD50=2.2 mg/kg body weight of the white mouse). As a consequence of the relatively high radioactivity (220 μCi/mg) 2 gives during storing a degradation product, which can be separated by chromatography on Sephadex G-25 or LH-20 using water as eluent, and whose UV-spectrum indicates a sulfoxide structure.
    Notes: Durch Reduktion der Ketogruppe des Ketophalloidins (1) mit 3H-haltigen NaBH4 wird ein radioaktives Desmethylphalloin (2) erhalten, das etwa dieselbe Toxizität wie Phalloidin besitzt. Infolge der hohen spezif. Aktivität (220 μCi/mg) entsteht beim Lagern aus 2 ein chromatographisch an Sephadex G-25 oder LH-20 in Wasser abtrennbares Zersetzungsprodukt, dessen UV-Absorptionskurve auf das Vorliegen einer Sulfoxid-Struktur hindeutet.
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  • 39
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    Liebigs Annalen 726 (1969), S. 13-18 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Phosphorus Pentafluoride and Boron Trifluoride in Liquid TrifluoromethanePhosphorus pentafluoride and boron trifluoride form conducting solutions in liquid trifluoromethane. The adducts (CH3)3N·PF5 and (CH3)3N·BF3 and also the salts [(CH3)3NH] [PF6] and [(CH3)3NH][BF4], respectively, may be obtained from these solutions by addition of trimethylamine. Complex anions containing trifluoromethyl ligands are not formed.
    Notes: Phosphor(V)-fluorid bzw. Bor(III)-fluorid zeigen in flüssigem Trifluormethan elektrisches Leitvermögen. Aus den Lösungen lassen sich mit Trimethylamin die Addukte (CH3)3N· PF5 bzw. (CH3)3N·BF3 und die Salze [(CH3)3NH][PF6] bzw. [(CH3)3NH][BF4] gewinnen. Trifluormethylhaltige Komplex-Anionen werden nicht gebildet.
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  • 40
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    Liebigs Annalen 726 (1969), S. 36-41 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Carbenes Derived from Bicyclo[3.3.0]octaneBicyclo[3.3.o]octane derivatives with divalent carbon in position 2 show little tendency to undergo intramolecular insertion with formation of tricyclo[3.2.1.02,8]octane derivatives. The tosylhydrazone of 2-bicyclo[3.3.0]octanone (1) yields predominantly 2-bicyclo[3.3.0]octene (2). the tosylhydrazone 7 of 10 bicyclo[3.3.0]octene-4-one prefer intermolecular reactions 9formation of ether) and affords less than 10% fo 4-tricyclo[3.2.1.02,8] octene (8).
    Notes: Carbene der Bicyclo[33.30]octan-Reihe mit zweibindigem Kohlenstoff in 2-Stellung zeigen geringe Neigung zu intramolekularer Einschiebung unter Bildung von Tricyclo[3.2.1.02.8]-octan-Derivaten. Aus Bicyclo[3.3.0]octanon-(2)-tosylhydrazon (1) entsteht bei alkalisch thermischer Spaltung vorwiegend Bicyclo[3.3.0]octen-(2) (2). Bicyclo[3.3.0]octen-(1)-on(4) tosylhydrazon (7) weicht auf intermolekulare Reaktionen (äther-Bildung) aus und liefert maximal 10% Tricyclo[3.2.1.02.8]octen-(4) (8).
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  • 41
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    Liebigs Annalen 726 (1969), S. 77-80 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: A New Preparation of AziridinesAddition of chlorine and acetonitrile to olefins yields dichloroimines 1. By methanolysis of 1, followed by acid hydrolysis, we obtained via the iminoesters 4 the β-chloroamines 5, which are easily converted into aziridines 3. It is not necessary to isolate the intermediate products.
    Notes: Eie Addition von Chlor und Acetonitril an Olefine ergibt Dichlorimine 1. Durch Methanolyse von 1 und anschließende saure Hydrolyse erhielten wir über die Iminoester 4 die β-Chloramine 5, die sich leicht in Aziridine 3 überführen lassen. Die Isolierung der Zwischenprodukte ist nicht erforderlich.
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  • 42
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    Liebigs Annalen 727 (1969), S. 106-109 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Syntheses with Quinones in situ, VII 1). Preparation of 7-Dimethylamino-2-hydroxyphenothiazin-3-one7-Dimethylamino-2-hydroxyphenothiazin-3-one (4) is obtained for the first time by using 2-amino-5-dimethylanilin-thiosulfuric acid (1) as starting material. There are two different procedures, the second procedure allows the isolation of the intermediate indophenol.
    Notes: 7-Dimethylamino-2-hydroxy-phenothiazinon-(3) (4) wird auf zwei Wegen aus 2-Amino-5-dimethyl-anilin-thioschwefelsäure (1) erstmalig dargestellt. Bei dem zweiten Reaktionsweg läßt sich die Indophenol-Zwischenstufe isolieren.
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  • 43
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    Liebigs Annalen 727 (1969), S. 125-129 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: A Novel Synthesis of AntamanidBy cyclization of the linear decapeptide phenylalanyl-phenylalanyl-prolyl -prolyl-phenyl-alanyl-phenylalanyl-valyl-prolyl-prolyl-alanine (position 5 → 4 in formula 1,) with the help of dicyclohexylcarbodiimide/N-hydroxy-succinimide (DCC/HOSu) antamanid (1,) is obtained in a 36.5% yield.
    Notes: Durch Ringschluß des linearen Decapeptids Phe-Phe-Pro-Pro-Phe-Phe-Val-Pro-Pro-Ala (Stellung 5 → 4 in Formel 1) mittels Dicyclohexylcarbodiimid/N-Hydroxy-succinimid wird das cyclische Decapeptid Antamanid in 36.5 proz. Ausbeute erhalten.
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  • 44
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The Catalytic Conversion of Olefins, I If'). Synthesis of cis,trans-l.5-Cyclodecadiene and I,trans-4.9-Decatriene. Co-oligomerization of Butadiene with EthyleneButadiene and ethylene can react together in the presence of “naked nickel” or nickel ligand catalytic systems to give cis,trans-1,5-cyclodecadiene (4; in yields of up to 80%). The intermediate 1 rearranges thermally to cis-1,2-divinylcyclohexane (6). 1, trans-4.9-Decatriene (5) is formed preferentially from butadiene and ethylene at 100°. Other unsaturated systems may also be included in the co-oligomerization reaction.
    Notes: Mit Hilfe von “nacktem Nickel” bzw. von Ligand/Ni-Katalysatoren können Butadien und äthylen zum cis.trans-Cyclodecadien-(1.5) (4) zusammengelagert werden (Ausbeute bis zu 80%). 4 lagert sich thermisch in cis-1.2-Divinyl-cyclohexan (6) um. Bei 100° entsteht aus Butadien und äthylen bevorzugt Decatrien-(1.trans-4.9) (5). In die Mischoligomerisation können auch andere ungesättigte Systeme einbezogen werden.
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  • 45
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions with Diazocarbonyl Compounds, XXXIII1). Reaction of o-Quinone Diazides with Ethyl p-Nitrophenylacetate and p-Nitrobenzylcyanideo-Quinone diazides react with p-NO2-C6H4-Ch2-CO2C2H5 and p-NO2-C6H4-CH2-CN to 2-hydroxyphenylhydrazones of the related keto compounds (table 1). The substances 1-9 are indicators. The cyano compound 8 shows solvatochromy reaching over the whole visible spectrum. The colour of the solution is related to the ability of the solvent to solvatise protons.
    Notes: o-Chinondiazide reagieren mit p-Nitrophenyl-essigsäureäthylester sowie mit p-Nitrobenzylcyanid zu 2-Hydroxy-arylhydrazonen der entsprechenden Keto-Verbindungen (Tab. 1). Die Substanzen 1-9 sind Indikatoren. Die Cyan-Verbindung 8 zeigt eine über das ganze sichtbare Spektrum gehende Solvatochromie, wobei ein Zusammenhang zwischen der Lösungsfarbe und der Fähigkeit des Lösungsmittels, Protonen zu solvatisieren, besteht.
    Additional Material: 3 Tab.
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  • 46
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    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 727 (1969), S. 228-230 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Mesomeric Kations, I. Synthesis of S-Aryl-thiuronium SaltsS-Aryl-tetramethyl-thiuronium perchlorates (3) are synthesized by reaction of tetramethylthiourea with activated aromatic halogen compounds (2) or with substituted diazonium salts. The reaction of tetramethylchloroformamidinium chloride (4) with thiophenols also gives the compounds 3 in high yields.
    Notes: Zur Synthese von S-Aryl-tetramethylthiuroniumperchloraten (3) läßt sich Tetramethylthioharnstoff mit aktivierten Halogenbenzolen (2) oder mit Diazoniumsalzen arylieren. Außerdem führt die Umsetzung von Tetramethyl-chlorformamidiniumchlorid (4) mit Thiophenolen ebenfalls glatt zu den Verbindungen 3.
    Additional Material: 1 Tab.
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  • 47
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 728 (1969), S. 12-16 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reaction of Iodosobenzene dichloride with Symmetrical EthersIodosobenzene dichloride (1) reacts with symmetrical ethers 2 under exposure to light, yielding monochloroethers 3. The formation of 1,2-dichloroethers 9, which are formed by interaction of chlorine with ethers 2, is not observed. The reaction of 1 with 2 can be explained by means of a chain reaction of C6H5-I -Cl radicals.
    Notes: Phenyljodidchlorid (1) reagiert mit symmetrischen äthern 2 bei Lichteinwirkung zu Monochloräthern 3. Das Auftreten von 1.2-Dichloräthern 9, die bei der Einwirkung von Chlor auf äther 2 entstehen, wird nicht beobachtet. Mit einer Kettenreaktion über C6H5-J.-Cl-Radikale läßt sich die Umsetzung von 1 mit 2 zu Monochloräthern 3 erklären.
    Additional Material: 2 Tab.
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  • 48
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 728 (1969), S. 36-43 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: I,2-Dithia-cyclopentenes, X V1). 3-Halogeno-I,2-dithiolium-compounds and Compounds with Positive Halogen3, 5, 9, 10 have been prepared from 3-halogeno-1,2-dithiolium-compounds and compounds with positive halogen. The 3-halogeno-5-amino-1,2-dithiolium-compound 13 does not react; that is interpreted by resonance structures of 13.
    Notes: 3-Halogen-1.2-dithiolium-Verbindungen mit Chlor oder dem Phenyl-Rest in 5-Stellung reagieren mit Substanzen, die „positives Halogen“ enthalten, unter Eliminierung von elementarem Halogen zu Verbindungen vom Typ 3, 5, 9, 10. Die 3-Halogen-5-amino-1.2-dithiolium-Verbindung 13 reagiert nicht; Mesomeriebetrachtungen erklären den Befund.
    Additional Material: 3 Tab.
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  • 49
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 728 (1969), S. 64-87 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Studies on Cyclohexenes, I. Synthesis and Reactions of 3-Amino-4-phenyl-cyclohexenes-(l), a Novel Class of AnalgesicsEthyl atropate (1a) and related alkenes (1b-e) undergo diene-(1.4)-cycloaddition reactions with the electron-rich 1-amino-butadienes-(1,3) 2a-e to give the stable, stereoisomeric 3-amino-4-phenyl-cyclohexenes-(1) 3a-i and 4a-i. The ratio of the isomers does not depend on the dielectric constant of the solvent used in case of 3r-dimethylamino-4c-ethoxycarbonyl-4t-phenyl-cyclohexene-(1) (3a) and 3r-dimethylamino-4t-ethoxycarbonyl-4c-phenyl-cyclohexene-(1) (4a). It however depends on the spatial requirements of the substituents of the alkene and diene (table 1). Structure of 3a and 4a have been established by NMR, mass and infrared spectra analysis and by degradation. - Assigned conformational preferences to 3a-i and 4a-i are confirmed by the hydrogenation rate of the cyclohexene double bond, by supra-annular effects and by the basicity constants of the hydrogenated and nonhydrogenated compounds. - All cyclohexenes 3a-i and 4a, e, g, i are active analgesics. The cyclohexanes 7-10, 17, and 22-25 have no or only weak analgesic properties.
    Notes: Atropasäureäthylester (1a) und verwandte Alkene (1b-e) gehen mit den Elektronen-reichen 1-Amino-butadienen-(1.3) 2a-e Dien-(1.4)-Cycloadditionen ein, die zu stabilen, stereoisomeren 4-Phenyl-3-amino-cyclohexenen-(1) 3a-i und 4a-i führen. Das Verhältnis der Isomeren ist beim 3r-Dimethylamino-4t(bzw. 4c)-phenyl-4c(bzw. 4t)-äthoxycarbonyl-cyclohexen-(1) (3a bzw. 4a) unabhängig von der Dielektrizitätskonstanten des bei der Addition verwendeten Lösungsmittels, jedoch abhängig von der Raumerfüllung der Liganden am En und Dien (Tab. 1). Die Struktur von 3a und 4a wird durch Massen-, NMR und IR-spetroskopische Untersuchungen sowie durch Abbau bewiesen. Mittels Konformationsbetrachtungen gewonnene Aussagen über den räumlichen Bau von 3a-i und 4a-i werden bestätigt vom Geschwindigkeitsverlauf der Hydrierung der Ring-Doppelbindung, von supra-annularen Effekten und den Basizitätskonstanten der hydrierten bzw. nicht-hydrierten Verbindungen. - Alle Cyclohexene 3a-i und 4a,e,g,i besitzen analgetische Aktivität; die Cyclohexane 7-10, 17 und 22-25 besitzen keine oder nur schwache analgetische Eigenschaften.
    Additional Material: 11 Tab.
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  • 50
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    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 728 (1969), S. 115-143 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Metal Complexes of PorphyrinsThe preparation of a series of porphyrin metal complexes is described, and the widely varying spectra of porphyrin complexes are interpreted in terms of known and newly discovered facts. The salts of ms-tetrasubstituted porphins have recently been recognized as derivatives of alloporphins (6); similarly, the porphyrins of the hemin and chlorophyll series form olivegreen or brown allo-complexes. The constitution 8 hitherto assigned to all porphin complexes actually only applies to the red-normal complexes including oxyhemoglobin. Valence-tautomeric chromophores such as 11, 15, and others are to be considered for allo-complexes including hemin.
    Notes: Die Darstellung einer Reihe von Porphyrin-Metall-Komplexen wird beschrieben. Unter Berücksichtigung von bekanntem und neuem Tatsachenmaterial wird eine Deutung der unterschiedlichen Elektronenspektren der Porphyrinkomplexe gegeben. Ausgehend von Salzen ms-tetrasubstituierter Porphine, die als Alloporphin-Derivate (6) erkannt wurden, werden olivgrüne bis braune Metallchelate von Porphyrinen der Hämin- und Chlorophyll-Reihe als Allokomplexe aufgefaßt. Die bisher den Porphyrin-Komplexen allgemein zuerteilte Konstitution 8 gilt nur für die roten Normalkomplexe, denen auch Oxyhämoglobin zuzurechnen ist. Für die Allokomplexe, zu denen Hämin gehört, werden Valenz-tautomere Chromophore wie 11, 15 und andere angenommen.
    Additional Material: 4 Ill.
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  • 51
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    Weinheim : Wiley-Blackwell
    Liebigs Annalen 728 (1969), S. 184-192 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: N-Substituted Derivatives of Dehydroubietylamine and DehydroabietylguanidineThe following derivatives of dehydroabietylamine have been synthesized in order to investigate their antimicrobial activity: N-monoalkyl- and N.N-dialkyl-dehydroabietylamines; dehydroabietylguanidines, which are substituted at the N- or N′-atom by an alkyl-, substituted alkyl-, acyl-, amino- or nitro-group; dehydroabietylurea, -thiourea, salts of dehydroabietylisourea and -isothiourea, quaternary dehydroabietylammonium salts and 2-dehydroabietylamino-pyrimidine.
    Notes: Zur Untersuchung ihrer antimikrobiellen Wirkung werden aus Dehydroabietylamin dargestellt: N-Monoalkyl- und N.N-Dialkyl-dehydroabietylamine, am N- oder N'-Atom durch eine Alkyl-, substit. Alkyl-, Acyl-, Amino- oder Nitro-Gruppe substituierte Dehydroabietylguanidine, Dehydroabietylharnstoff, -thioharnstoff, Salze des Dehydroabietylisoharnstoffs und -isothioharnstoffs, quaternäre Dehydroabietylammoniumsalze und 2-Dehydroabietyl-amino-pyrimidin.
    Additional Material: 2 Tab.
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  • 52
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    Weinheim : Wiley-Blackwell
    Liebigs Annalen 729 (1969), S. 1-7 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Organometallic Compounds of the Groups IVa and Va, I. Alkoxytriphenylursine- and Alkoxytriphenylantimony HalidesThe reactions of tert.-butylhypohalities (2a and b) with triphenylarsine (1c) and triphenyl-antimony (1a) have been investigated an dht eproperties of the triphenyl-tert.-butoxyarsine-and - antimony halides (3a-d) formed have been examined.
    Notes: Die Umsetzung von tert.-Butylhypohalogeniten (2a und b) mit Triphenylarsin (1c) un d-stibin (1a) und die Eigenschaften der dabei entstehenden Triphenyl-tert.-butyloxy-arsen - und -antimonhalogenide (3a-d) werden untersucht.
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  • 53
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    Weinheim : Wiley-Blackwell
    Liebigs Annalen 729 (1969), S. 8-20 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Wagner- Meerwein Rearrangements in the Bicyclo[3.2.2rsqb;nonane Series I )Deamination of the epimeric 6-aminobicyclo[3.2.2]non-8-enes (6 and 7) and 6-aminobicyclo-[3.2.2]nonanes (8, X = NH2 and 9) mainly proceeds via a stereospecific rearrangement to yield exo-alcohols of hte bicyclo[3.3.1]nonane or bicyclo[4.2.1]nonane series with high stereospecifity. In addition, tricyclo[4.2.1.02.8]nonan-7-ol (10) was produced from the endo-amin 7. - In the presence of silver bromide 2-bromobicyclo[3.2.2]nonane (8, X = Br) rearranges to 2-bromobicyclo[3.3.1]nonane (2, Y = Br). - Both the dehydration of bicyclo[3.2.2]nonan-6-ol (1, X = OH) with phosphoric acid and the acid-catalyzed rearrangement of bicyclo-[3.2.2]non-6-ene (12) give rise to bicyclo[3.3.1]non-2-2ne (11, X = H). The reaction of 12 with an excess of monoperphthalic acid yields syn- and anti-bicyclo[3.3.1.13.9]decane (17). -The deamination of 2e-aminomethylbicyclo[3.2.1]octane (18 gives a mixture of alcohols consisting of bicyclo-[4.2.,1]nonan-3-ol (36), bicyclo[4.2.1]nonan-2-ol (3, Y = OH), bicyclo[3.3.1]nonan-2-ol (2, Y = OH), and 2a-and 2e-methylbicyclo[3.2.1]octan-2e- and 2a-ols (20 and 19).
    Notes: Die Desaminierungen der epimeren 6-Amino-bicyclo[3.2.2]nonene-(8) (6 und 7) und 6-Aminobicyclo[3.2.2]nonane (8, X = NH2, und 9) führen stereospezifisch zu exo-Alkoholen der Bicyclo[3.3.1]nonan- oder Bicyclo[4.2.1]nonan-Reihe. Das endo-Amin 7 liefert daneben Tricyclo[4.2.1.02.8]nonanol-(7) (10). - 6-Brom-bicyclo[3.2.2]nonan (8, X = Br) lagert sich in Gegenwart von AgBr in 2-Brom-bicyclo[3.3.1]nonan (2, Y = Br) um. -Die Dehydratisierung von Bicyclo[3.2.2]nonanol-(6) (1, X = OH) mit Phosphorsäure und die säurekatalysierte Umlagerung von Bicyclo[3.2.2]nonanol-(6) (1, X = OH) mit Phosphorsäure und die säurekatalysierte Umlagerung von Bicyclo[3.2.2]nonen-(6) (12) führen zu Bicyclo[3.3.1]nonen-(2) (11, X = H). - Aus 12 bilden sich mit überschüss. Monoperphthalsäure syn- und anti- Bicyclo[3.3.1]nonen-(2)-ol-(9) (14 und 15) sowie vermutlich 10-Oxatricyclo[3.3.1.13.9]decan (17). - Bei der Desaminierung des 2e-Aminomethyl-bicyclo[3.2.1]octans (18) entstehen Bicyclo[4.2.1]nonanol-(3) (36), Bicyclo[4.2.1]nonanol-(2) (3), Y = OH), Bicyclo[3.3.1]nonanol-(2) (2, Y = OH) sowie 2a und 2e-Methyl-bicycol[3.2.1]octanol-2c und 2a) (20 und 19).
    Additional Material: 1 Tab.
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  • 54
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    Weinheim : Wiley-Blackwell
    Liebigs Annalen 729 (1969), S. 52-63 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions of Ally1 Alcohols with Active Methine and Methylene Compoundsγ.δ-Unsaturated ketones 4 are intermediates in several syntheses of natural products. They may be obtained from allyl alcohols and β-keto esters. Novel synthetic approaches to γ.δ-unsaturated ketones 4 and the related compounds 12, 14, 16, and 18 are described (tables 7-10). The investigations lead to a new synthetic route for the preparation of the juvenile hormone (10).
    Notes: γ.δ-Ungesättigte Ketone 4, herstellbar aus Allylalkoholen und β-Ketoestern, sind Zwischenprodukte verschiedener Naturstoff-Synthesen. Es werden neue Synthesemöglichkeiten von 4 und den damit verwandten Verbindungen 12, 14, 16 und 18 (Tabb. 7 - 10) beschrieben. Die Arbeiten führen zu einem Herstellungsverfahren des Juvenilhormons (10).
    Additional Material: 1 Ill.
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  • 55
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    Weinheim : Wiley-Blackwell
    Liebigs Annalen 729 (1969), S. 69-72 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions with Cyclopentadienones, XVII).1,4-Cycloaddition of Dibenzoyldiimide to CyclopentadienonesThe cyclopentadienones 2-7 and dibenzoyldiimide (1) give the corresponding 1,4-compounds 8-12. By heating in xylene the product 8 rearranges to the lactone 13. Reaction mechanisms are discussed.
    Notes: Die Cyclopentadienone 2-7 werden mit Dibenzoyldiimid (1) zu den entsprechenden 1.4-Addukten 8-12 umgesetzt. Erhitzen von 8 in Xylol liefert das Lacton 13. Die Reaktionsmechanismen werden diskutiert.
    Additional Material: 1 Tab.
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  • 56
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    Weinheim : Wiley-Blackwell
    Liebigs Annalen 729 (1969), S. 106-118 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthese of Phosphinimine CompoundsA number of new phosphinimine compounds of s-triazines is obtained by the reaction of triamino-s-triazine (9) with triphenylphosphine and halogenes (table 1) or of trichloromelamine (17, table 2) or hexachloromelamine (26, table 3) with tertiary phosphines. The components react in the absence of dehydrohalogenating compounds. Only one reaction step is necessary for the formation of the products. All these methods give pure products in good yields.
    Notes: Eine Reihe neuer Phosphinimin-Derivate von s-Triazinen (Tab. 1) wird in einer Stufe mit groβer Reinheit und hohen Ausbeuten aus Triamino-s-triazinen (9), Triphenylphosphin und Halogenen in Abwesenheit von Halogenwasserstoff bindenden Verbindungen sowie aus Trichlormelamin (17, Tab. 2) oder Hexachlormelamin (26, Tab. 3) und tertiären Phosphinen erhalten.
    Additional Material: 3 Tab.
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  • 57
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    Weinheim : Wiley-Blackwell
    Liebigs Annalen 729 (1969), S. 146-151 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: A New Synthesis of 1,2-BenzisothiazolesA new method has been found for the preparation of 1,2-benzisothiazoles (1). The compounds are formed by reaction of dihalomethyl-2,6-dihalobenzenes with elementary sulfur and ammonia in a solvent.
    Notes: Es wurde eine neue Herstellungsweise für 1.2-Benzisothiazole (1) gefunden. Die Verbindungen entstehen durch Umsetzen von 2.6-Dihalogen-benzylidenhalogeniden mit elementarem Schwefel und Ammoniak in einem Lösungsmittel.
    Additional Material: 3 Tab.
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  • 58
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    Weinheim : Wiley-Blackwell
    Liebigs Annalen 729 (1969), S. 184-192 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Ubiquinones and Related Compounds, XV. Photochemical Reaction of Ubiquinone-7trans-Ubiquinone-7 (1) is converted to several compounds by irradiation of its ethanolic solution with sunlight. One of them, 2a, had been reported previously by us to be an isomer in which the β,γ-double bond of 1 has migrated to the α,β-position. 2a is reinvestigated and its correct structure found to be trans-γ-ethoxy-isoubiquinone-7 (chart 1). In methanol 1 gives the γ-methoxy compund 2b in the same manner. The configurations of α,β-double bond in isoubiquinone groups, 2a, 2b, 2c, and 8 were deduced from the n.m.r. spectra of the corresponding hydroquinone diacetates 3a, 3b, 3c, 9 (figure 1). The mechanism of the photochemical reaction is discussed (chart 2).
    Notes: trans-Ubichinon-7 (1) geht in äthanol durch Sonnenbestrahlung in mehrere Substanzen über. Eine davon, 2a, wurde früher von uns als Isomeres von 1 angesehen, in welchem die β-γ-Doppelbindung in die α.β-Position verschoben ist. Die Struktur von 2a lieβ sich jetzt als trans-γ-äthoxy-isoubichinon-7 richtigstellen (Schema 1). 1 ergibt in Methanol analog das Methoxy-Derivat 2b. Die Konfiguration der α.β-Doppelbindung in der Isoubichinon-Gruppe 2a-c und 8 kann durch die NMR-Spektren ihrer Diacetylhydrochinone 3a-c und 9 festgestellt werden (Abb. 1). Der Mechanismus dieser Photoreaktion wird diskutiert (Schema 2).
    Additional Material: 1 Ill.
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  • 59
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    Weinheim : Wiley-Blackwell
    Liebigs Annalen 729 (1969), S. 249-250 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On Natural Tannins, XLIII). (-)-Chebulic Acid from AlgarobillaChebulic acid (1, R = H) is prepared by acid hydrolysis of Algarobilla extracts. It has been shown to be the optical antipode of the acid obtained from Myrobalanes.
    Notes: Aus Algarobilla-Extrakten wird durch Hydrolyse Chebulsäure (1, R = H) abgespalten, die sich als das Spiegelbild der aus Myrobalanen erhaltenen Säure erweist.
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  • 60
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    Liebigs Annalen 729 (1969), S. 246-248 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Enol Ethers, VIII. Reactions of Aldehydes with Electron-rich Alkenes1-Dimethylamino-1-ethoxyethylene (1) and 1,1-dipiperidinoethylene (2) react with aromatic aldehydes 3 to give cinnamamides. Coumarines are obtained on reaction with salicylic aldehydes.
    Notes: 1-Dimethylamino-1-äthoxy-äthylen (1) und 1.1-Dipiperidino-äthylen (2) reagieren mit aromatischen Aldehyden 3 zu Zimtsäureamiden. Mit Salicylaldehyden erhält man in glatter Reaktion Cumarine.
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  • 61
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions of CH-Active Compounds with Azides, XXVII ). Syntheses of a-Diazo-imines und Isomeric 1,2,3-Triazoles and Their Conversion into a-Diazo-immonium Salts1-Anilino-3-oxo-indenes 6a-f are converted into 1-oxo-3-arylimino-2-diazo-indanes 8a-c or 1-oxo-3-aryl-3H,8H-indeno [1,2-d]triazoles 9d-f by diazo group transfer with p-toluenesulfonyl azide in ethanol/potassium ethoxide. Both classes of substances add mineral acids to form 1-oxo-3-arylimmonium-2-diazo-indane-salts 10a-f. Treatment of the immonium salts with potassium hydroxide yields the α-diazo-imines 8a, b, e and f. 8c hydrolyses to give 1,3-dioxo-2-diazo-indane; 8d, which changes largely to 9d by cyclisation, is accessible by thermal ringopening of the latter. 1-Anilino-3-oxo-cyclohexenes-(1) 12a-f are transformed into 4-oxo-1-aryl-4,5,6,7-tetrahydro-benzotriazoles (14a-f) by diazo group transfer with high yields.
    Notes: 1-Anilino-3-oxo-indene 6a-f liefern bei der Diazogruppen-übertragung mit p-Toluolsulfonsäure-azid in äthanol/Kaliumäthylat 1-Oxo-3-arylimino-2-diazo-indane 8a-c bzw. 1-Oxo-3-aryl-3H.8H-indeno[1.2-d]triazole 9d-f. 8 und 9 addieren Mineralsäuren - 9 unter Ringöffnung - zu 1-Oxo-3-arylimmonium-2-diazo-indan-Salzen 10a-f. Mit Kaliumhydroxid erhält man daraus die α-Diazo-imine 8a, b, e und f. 8c hydrolysiert weiter zu 1.3-Dioxo-2-diazo-indan; 8d cyclisiert größtenteils zum Triazol 9d, ist aber durch dessen direkte thermische Isomerisierung zugänglich. 1-Anilino-3-oxo-cyclohexene-(1) 12a-f werden durch Diazogruppen-übertragung mit hohen Ausbeuten in 4-Oxo-1-aryl-4.5.6.7-tetrahydrobenzotriazole 14a-f umgewandelt.
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    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Absolute Configuration of Optically Active, Naturally Occurring Dihydroisocoumarins, IIIs2).Determination of the Absolute Configuration of Agrimonolide and MelleineBy degradation with ozone and performic acid (S)-3-hydroxy-adipic acid is obtained from both agrimonolide (1) and (-)-β-tetralol (4), which is characterized as di-hydrazide 3. Therefore 1 and 4 have S-configuration at position 3 and 2 respectively. The positive CD at 260 mμ of 1 and phyllodulcine (7) is a proof of configurative identity. In contrast, melleine (8) shows at 257 mμ negative CD and therefore has R-configuration.
    Notes: Durch Abbau mit Ozon und Perameisensäure wird aus Agrimonolid (1) und (-)-β-Tetralol (4) die gleiche (S)-3-Hydroxy-adipinsäure erhalten und als Dihydrazid 3 charakterisiert. Damit geht für 1 und 4 die S-Konfiguration and C-3 bzw. C-2 hervor. Der positive CD von 1 und Phyllodulcin (7) bei 260 mμ beweist deren konfigurative übereinstimmung. Da der CD des Melleins (8) - wie 7 ein Salicylsäure-Derivat - bei 257 mü negativ ist, muß hier auf R-Konfiguration am C-3 geschlossen werden.
    Additional Material: 1 Ill.
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  • 63
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    Liebigs Annalen 729 (1969) 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 64
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    Liebigs Annalen 729 (1969), S. 21-26 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Protonated Methylbenzene Tetrachloroaluminate ComplexesWell defined complexes from methyl substituted benzenes and aligated by proton magnetic resonance (figure 1, table 1). A few of these compounds can be characterized as σ-complexes. Under the conditions used σ-protonation requires a benzene ring with at least three methyl substituents and a 1,3,5-type of substitution. In all other cases complexes are formed, in which π-bonding is likely.
    Notes: Definierte Komplexe aus Methyl-substituierten Benzolen und Aluminiumchlorid/Chlorwasserstoff wurden erhalten und auf ihre NMR-Signale untersucht (Abb. 1, Tab. 1) Nur ein Teil dieser Verbindungen kann als σ-Komplex charakterisiert werden. Unter den angewandten Bedingungen ist für die σ-Protonierung Substitution mit wenigstens drei Methyl-Gruppen in 1.3.5-Stellung erforderlich. In allen anderen Fällen ist π-Komplex-Bildung wahrscheinlich.
    Additional Material: 1 Ill.
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  • 65
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    Liebigs Annalen 729 (1969), S. 40-51 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Production and Reactions of N- MonoalkylamidosulfonylchloridesN-Monosubstituted amidosulfonylchlorides (1) may optimally be obtained by reaction between N-monosubstituted ammonium chlorides and sulfuryl chloride in acetonitrile. N-Monosubstituted amidosulfonylchlorides are very active intermediates, which react especially with reactive H containing compounds to give the free acids 2 (R = H), the esters or thioester 2,5, and 6, and the amides 7 and 8. The hydrogen of the amino group can also be substituted. In this way new compounds are accessible and other already known compounds can be produced more easily.
    Notes: Unter den Methoden zur Herstellung N-monosubstituierter Amidosulfonylchloride (1) erweist sich die Umsetzung von N-monosubstituierten Ammoniumchloriden mit Sulfurylchlorid in Acetonitril als am besten geeignet. N-Monosubstituierte Amidosulfonylchloride sind sehr reaktive Zwischenprodukte, die mit reaktionsfähigen, H-enthaltenden Verbindungen zu den freien Säuren 2 (R = H), den Estern bzw. Thioestern 2, 5 und 6 sowie den Amiden 7 und 8 reagieren können; außerdem besitzen sie einen leicht substituierbaren Wasserstoff an der Amino-Gruppe. Mit ihnen sind Verbindungen präparative leicht zugänglich, die bisher nicht oder nur umständlich gewonnen werden konnten.
    Additional Material: 8 Tab.
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  • 66
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    Liebigs Annalen 729 (1969), S. 73-82 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Catalytic Hydrogenation of PurinesHydrogenation of purines over platinum or palladium occurs initially, if at all, in the 1,6 positions (e. g. 1 → 4). The 1,6-dihydropurines, which can still be acetylated in the 7 or 9 position, can be hydrogenated further to hexahydro- and perhydropurines (20 and 13, respectively).
    Notes: Purine werden an Platin oder Palladium, wenn überhaupt, zuerst in 1.6-Stellung hydriert (z. B. 1 → 4); die 1.6-Dihydro-purine, die noch in 7- bzw. 9-Stellung acetylierbar sind, können dann weiter zu Hexahydro- bzw. Perhydro-purinen (20 bzw. 13) hydriert werden.
    Additional Material: 1 Tab.
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  • 67
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    Weinheim : Wiley-Blackwell
    Liebigs Annalen 722 (1969) 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 68
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    Liebigs Annalen 722 (1969), S. 29-37 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: a-Hydrazonocarboxylic Acid Azides, I. Aliphatic α-Hydrazonocarboxylic Acid AzidesThe title compounds 2, 5a-c, 6a-e are prepared by reaction of the analogous α-hydrazonocarboxylic acid hydrazides (1, 7a-c, 8a-e) with nitrous acid. Both classes form Z- and E-isomers. The α-hydrazonocarboxylic acid hydrazides (1, 8e), that are unsubstituted in the hydrazono group, prefer the Z-form, whereas those (7a-c, 8a- d), that are substituted in the hydrazono group, prefer the E-form. The Z-azides, prepared from the Z-hydrazides, are unstable and lose hydrazoic acid. The E-azides, prepared from the E-hydrazides, are stable, but change into the unstable Z-isomers on standing at room temperature when exposed to light. On boiling in toluene the E-isomers lose nitrogen to form substituted 1,2,4-triazol-5-ones (15a-c, 16a-d).
    Notes: Die Titelverbindungen 2, 5a-c, 6a-e entstehen aus den entsprechenden α-Hydrazonocarbonsäurehydraziden (1, 7a-c, 8a-e) durch Reaktion mit salpetriger Säure. Beide Substanzklassen treten in Z- und E-Form auf. Die in der Hydrazono-Gruppe unsubstituierten α-Hydrazonocarbonsäurehydrazide (1, 8e) liegen bevorzugt in der Z-Form, die entsprechend substituierten Hydrazide (7a-c, 8a-d) überwiegend in der E-Form vor. Die aus den Z-Hydraziden entstehenden Z-Azide sind instabil und spalten Stickstoffwasserstoffsäure ab. Die aus den E-Hydraziden entstehenden E-Azide sind stabil, wandeln sich jedoch bei längerem Stehenlassen und gleichzeitiger Lichteinwirkung in die instabilen Z-Azide um. Beim Kochen der E-Azide in Toluol wird Stickstoff abgespalten und es bilden sich substituierte 1.2.4-Triazolone-(5) (15a-c, 16a- d).
    Additional Material: 3 Tab.
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  • 69
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    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Intramolecular Rearrangements of Bicyclo[2,2, heptanes, XI1). Rearrangement of 1- Methyl-7,2-norbornanecarbolactone in Sulfuric AcidIn the presence of concentrated sulfuric acid 1-methyl-7,2-norbornanecarbolactone (1) rearranges to 3exo-methyl- and 1-methyl-2,6-norbornanecarbolactones (2 and 5). The structure of the hitherto unknown lactone 5 is established.
    Notes: 1-Methyl-norbornan-carbolacton-(7.2) (1) lagert sich unter dem Einfluß konzentrierter Schwefelsäure in 3 exo-Methyl- und 1-Methyl-norbornan-carbolacton-(2.6) (2 und 5) um. Die Struktur des bislang unbekannten Lactons 5 wird bewiesen.
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  • 70
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    Liebigs Annalen 722 (1969), S. 232-233 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cycloaddition of Dichloroketene to 2-ButyneDichloroketene generated in situ, gives with 2-butyne the 1,2-cycloaddition product 2,3-dimethyl-4,4-dichlorocyclo-2-buten-1-on (1).
    Notes: In situ erzeugtes Dichlorketen addiert sich an Butin-(2) zum 2.3-Dimethyl-4.4-dichlor-cyclobuten-(2)-on-(1) (1).
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  • 71
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    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Studies on the Occurence of Hydrogen Transfer, 191). Specific Reductive Cleavage of Some Acyl Groups from Nitrogen at the Mercury CathodeElectron donators in the aromatic acyl group and in the amine component shift the reduction potentials of sulfonamides and of carbonamides to more negative values, and hinder the cathodic cleavage. Electron acceptors have the opposite effect. Aromatic ligands on the nitrogen atom change the reduction potentials to more positive values. The influence of the substituents on the reduction potentials follows the Hammett relationship. - If a potential difference of at least 0.2 V exists between acyl groups (which may be in the same molecule, or in different molecules), then selective cleavage of the acyl group having the more positive potentials is possible.
    Notes: In Sulfon und Carbonamiden mit aromatischem Acyl-Rest werden die Reduktionspotentiale durch Elektronen-Donatoren im Acyl-Rest und in der Amin-Komponente zu negativeren Werten verschoben; dabei wird die kathodische Spaltung erschwert. Elektronen-Acceptoren wirken umgekehrt. Aromatische Liganden am Stickstoff verlagern das Reduktionspotential zu positiveren Werten. Die Abhängigkeit der Reduktionspotentiale vom Substituenten gehorcht der Hammett-Beziehung. - Besteht zwischen den Acylamino-Gruppen, die im gleichen Molekül oder auch in verschiedenen Molekülen gebunden sein können, ein Potentialunterschied von wenigstens 0.2 V, so ist eine selektive Abspaltung der Acyl-Gruppe mit dem positiveren Potential möglich.
    Additional Material: 1 Ill.
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    Liebigs Annalen 723 (1969), S. 41-46 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Tertiary and Quaternary Salts of Hexahydro-pyrimidinesThe mono- and bis-tertiary salts 7, 11, 12 may be obtained by reaction of 1.3-dialkylhexahydro-pyrimidines and hydrogen chloride in suitable solvents. - The mono-quaternary salts 8-10 are formed from 1.3-dialkyl-hexahydro-pyrimidines and alkyl halides in ether. The bis-quaternary salts 5, 6 and 13-17 result by alkylation of 1.3-dialkyl-hexahydro-pyrimidines with methyl bromide, methyl iodide or trialkyloxonium fluoroborates in polar aprotic solvents or by reaction of α-halogen amines with γ-chloropropyl amines.
    Notes: Aus 1.3-Dialkyl-hexahydro-pyrimidinen und Chlorwasserstoff sind in geeigneten Lösungsmitteln die mono-sowie bis-tertiären Salze 7, 11, 12 zu gewinnen. - Die monoquartären Salze 8-10 entstehen aus 1.3-Dialkyl-hexahydro-pyrimidinen und Alkylhalogeniden in Äther. Die bis-quartären Salze 5, 6 und 13-17 sind durch Alkylierung von 1.3-Dialkyl-hexahydropyrimidinen mit Methylbromid oder -jodid sowie Trialkyl-oxoniumfluoroboraten in polaren, aprotischen Lösungsmitteln oder durch Umsetzung α-halogenierter Amine mit γ-Chlorpropylaminen zugänglich.
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    Liebigs Annalen 723 (1969), S. 201-204 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Concerning the Mechanism of Catalytic Proton-Transfer by Diazomethane, IIMethyl 3-hydroxy-2-naphthoate (8) gives with 1 mole phenyl isocyanate in the presence of 1 mole deuterodiazomethane (1.6 g-atom D/mole) an adduct 9-d0 free from deuterium; the same reaction carried out with deuterated 8 and non-deuterated diazomethane gives 9-d1. These results are in accordance with a proton-transfer by proton-bridge complexes, whereas they exclude the proton-transfer by methyldiazonium cations.
    Notes: 3-Hydroxy-naphthoesäure-(2)-methylester (8) bildet mit 1 Mol. Phenylisocyanat in Gegenwart von 1 Mol. Deuterodiazomethan (1.6 g-Atom D/Mol) das D-freie Addukt 9-d0; bei der Reaktion mit deuteriertem 8 und undeuteriertem Diazomethan entsteht dagegen 9-d1. Die Befunde lassen sich durch Protonen-Übertragung über Protonbrückenkomplexe erklären und schließen die Protonen-Übertragung durch Methyldiazonium-Kationen aus.
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  • 74
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    Liebigs Annalen 724 (1969), S. 24-29 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Conjugation in Macrocyclic Bond Systems, XIII1). Further Compounds of the Hexa-m-phenylene TypeThe preparation of the sterically overcrowded hexamethyl hexa-m-phenylene 2 is reported. Spectroscopic properties (u. v., 1H-n.m.r.) and mass spectra of 2 are discussed with regard to the strong deviation from coplanarity present in this system. Synthesis and properties of 8,2′;8′,2″;8″,2-tris(dibenzothiophenylene) (10), a coplanar a coplanar derivative of 1, are reported.
    Notes: Das sterisch stark behinderte Hexamethyl-hexa-m-phenylen 2 wird hergestellt. Die spektroskopischen Eigenschaften (UV, 1H-NMR) und das Massenspektrum von 2 werden unter dem Gesichtspunkt der hier vorliegenden starken Abweichung von der Komplanarität diskutiert. Über Synthese und Eigenschaften des 8.2′;8′.2″;8″.2-Tris-dibenzothiophenylens (10), eines ebenen Derivats von 1, wird berichtet.
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  • 75
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    Liebigs Annalen 724 (1969), S. 66-70 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Photochemical and Thermal 1,4-Cycloaddition of Enamides to 1,2- Dicarbonyl CompoundsThe enamides 2 and 6 can be added to benzil and o-chinones photochemically and thermally to give the 1,4-dioxen derivatives 3 and 7. The thermal addition follows a two-step mechanism, as is shown by the formation of the same 1,4-dioxen compound 7b from the addition of cis- and trans-enamide to 5.
    Notes: Die Enamide 2 und 6 addieren sich photochemisch wie thermisch an Benzil und o-Chinone zu den 1.4-Dioxen-Derivaten 3 und 7. Der Verlauf der thermischen Addition ist zweistufig, wie bei der Reaktion von cis- und trans-Enamid (6b bzw. 2b) mit 5 gezeigt wird, die zu demselben 1.4-Dioxen-Derivat 7b führt.
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  • 76
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    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Nitromethane Condensation with Dialdehydes, XVI1) S-Benzyl Substituted Nitrodithiols by cyclizing Bismercaptoalkylation of Nitromethane2-Nitrocyclohexanedithiols with trans-, chiro-, and cis-configuration (5-7) are formed by nitromethane-cyclization of glutaraldehyde in the presence of α-toluenethiol or by reaction of 2-nitrocyclohexane-1,3-diol (11) with α-toluenethiol, the product distribution being dependent on the reaction conditions. - Analogously, a 1,4-dinitrocyclohexanetetrathiol (15) is formed from 1,4-dinitro-1,4-dideoxy-neo-inositol (13), whereas its tetraacetate 16 gives 2-nitro-5-benzylmercaptophenol (17), as a result of aromatization followed by nucleophilic displacement of one nitro group by a mercapto moiety. - Configuration and conformation of the nitro dithiols and of the sulfones 8-10 obtained on oxidation are deduced from n.m.r. spectra.
    Notes: Nitromethan-Cyclisierung von Glutardialdehyd in Gegenwart von Benzylmercaptan oder Umsetzung von 2-Nitro-cyclohexandiol-(1.3) (11) mit Benzylmercaptan führt zu 2-Nitro-cyclohexan-dithiolen mit trans-, chiro- und cis-Konfiguration (5-7), deren Mengenverhältnis von den Reaktionsbedingungen abhängt. - Aus 1.4-Dinitro-1.4-Dinitro-1.4-didesoxy-neo-inosit (13) erhält man analog ein 1.4-Dinitro-cyclohexantetrathiol (15), aus dem Dinitrotetraacetat 16 dagegen, infolge Aromatisierung und nucleophiler Verdrängung einer Nitro- durch eine Mercapto-Gruppe, 2-Nitro-5-benzylmercapto-phenol (17). - Konfiguration und Konformation der Nitrodithiole sowie der durch Oxydation erhaltenen Sulfone 8-10 ergeben sich aus den NMR-Spektren.
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    Liebigs Annalen 724 (1969), S. 128-136 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Preparation und Hydrolysis of 4- Halogenomethylen-1.3-dioxolanes4-Halogenomethylen-1,3-dioxolanes (4a-o) are obtained by base-catalyzed addition of formaldehyde to 1-halogen-1-propyn-3-ols (3). Acid hydrolysis of the dioxolane derivatives 4 yields 1-halopropan-3-ol-2-ones (5a-f, i-o), which split off hydrogen halide to give 2,3-diketones 6 and 7a-c, if the hydroxyl group is attached to a primary or secondary carbon atom.
    Notes: Durch basenkatalysierte Addition von Formaldehyd an 1-Halogen-propin-(1)-ole-(3) (3) werden 4-Halogenmethylen-1.3-dioxolane (4a-o) erhalten. Die saure Hydrolyse von 4 führt zu 1-Halogen-propanol-(3)-onen-(2) (5a-f, i-o). Soweit diese eine primäre oder sekundäre Hydroxy-Gruppe enthalten (5a-f), werden sie beim Erwärmen in die 2.3-Diketone 6 bzw. 7a-c und Halogenwasserstoff gespalten.
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    Liebigs Annalen 724 (1969), S. 155-158 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: 1-(2- Hydroxyphenyl)-3,5-diphenyl-Δ2-pyrazolines2-Hydroxyphenylhydrazine hydrochlorides 1a-g and chalcone form 1-(2-hydroxyphenyl)-3,5-diphenyl-Δ2-pyrazolines (2a-g). The isolation of chalcone 2-hydroxyphenylhydrazones 3a and 3b depends on the substituents of the compounds 1a-g. - 1,3,5-Triphenyl-Δ2-pyrazolines show fluorescence, 1-(2-hydroxyphenyl)-3,5-diphenyl-Δ2-pyrazolines do not. Acetylation of the phenyl group leads to fluorescent compounds 4a-e.
    Notes: Aus den 2-Hydroxy-phenylhydrazin-hydrochloriden 1a-g, und Benzylidenacetophenon werden 1-[2-Hydroxy-phenyl]-3.5-diphenyl-Δ2-pyrazoline (2a-g) hergestellt. In Abhängigkeit von der Substitution der Verbindungen 1a-g, können bei gleichen Reaktionsbedingungen die Benzylidenacetophenon-2-hydroxy-phenylhydrazone 3a und 3b als Zwischenstufen isoliert werden. - Im Gegensatz zu 1.3.5-Triphenyl-Δ2-pyrazolinen fluoreszieren 1-[2-Hydroxyphenyl]-3.5-diphenyl-Δ2-pyrazoline nicht. Acetylierung der Hydroxyl-Gruppe führt zu fluoreszierenden Verbindungen 4a-e.
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    Liebigs Annalen 724 (1969), S. 183-193 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Triterpenes, XXVII1). The Structure of Musennin and DeglucomusenninThe bark of the roots of Albizzia anthelmintica (Brongn.) contains a mixture of saponins, the main components of which, musennin and deglucomusennin, have now been isolated. The sugar chains are attached to the 3-hydroxy group of the aglycon echinocystic acid. Deglucomusennin contains three molecules of l-arabino-pyranose in an unbranched chain. They are connected in α-1,2-position. Musennin has an additional molecule of D-glucose, in β-1,3-linkage to the last molecule of l-arabinose of the chain.
    Notes: Als Hauptkomponenten des Saponingemisches der Wurzelrinde von Albizzia anthelmintica (Brongn.) werden Musennin und Desglucomusennin erkannt, in denen jeweils eine Zuckerkette an die 3-Hydroxyl-Gruppe des Aglykons Echinocystsäure gebunden ist. Desglucomusennin enthält 3 Moll. l-Arabinose in Pyranoseform, die in unverzweigter α-1.2-Verknüpfung vorliegen. Musennin besitzt zusätzlich 1 Mol. D-Glucose, die in β-1.3-Form mit der endständigen Arabinose verbunden ist.
    Additional Material: 3 Tab.
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    Liebigs Annalen 725 (1969), S. 196-202 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: NMR-Spectroscopic Studies of Acyl GlycosesA NMR spectroscopical study of the p-cumaroyl-D-glucoses (1a-e), p-hydroxybenzoyl-D-glucose (2a-e), as well as of the p-cumaroyl-L-rhamnoses (3 and 4) and 5-p-cumaroyl-D-xylofuranose (5) was carried out (table 1). The configuration and conformation, and in the case of the 1-, 2-and 6-acyl-glucoses as well as of 4-p-cumaroyl-α-methyl-L-rhamnopyranoside (4) also the position of the acyl group, have been established. With the aid of synthetic sugar esters the structure of neobignonoside, neopetunoside, and negretein could be determined.
    Notes: Aus den NMR-Spektren von p-Cumaroyl- (1a-e), p-Hydroxy-benzoyl-D-glucosen (2a-e) sowie p-Cumaroyl-L-rhamnosen (3 und 4) und 5-p-Cumaroyl-D-xylofuranose (5) (Tab. 1) werden die Konformation, Konfiguration und im Falle der 1-, 2- und 6-Acylglucosen- sowie des 4-p-Cumaroyl-α-methyl-L-rhamnopyranosids (4) die Stellung des jeweiligen Acyl-Restes ermittelt. Mit Hilfe der synthetischen Zuckerester konnte die Struktur von Neobignonosid, Neopetunosid und Negretein geklärt werden.
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    Liebigs Annalen 722 (1969), S. 80-97 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Oxidation Products of Thioamides, XX1). Thiourea S-dioxidesThe thiourea S-dioxides 8, 15, and 16 are prepared by oxidation of N-mono- and N.N′-disubstituted thioureas with hydrogen peroxide. Treatment of N.N′-disubstituted thiourea S-dioxides with acids affords formamidines. When N.N′-dineopentylthiourea is oxidized only N.N′-dineopentylformamidine (19) can be isolated. The properties and reactions of the thiourea S-dioxides are compared with those of pyridinesulfinic acids.
    Notes: Bei der Oxydation N-mono- und N.N′-disubstituierter Thioharnstoffe mit H2O2 lassen sich die Thioharnstoff-S-dioxide 8, 15 und 16 isolieren. Durch Behandlung mit Säuren entstehen aus N.N′-disubstituierten Thioharnstoff-S-dioxiden Amidine; bei der Oxydation des N.N′-Di-neopentyl-thioharnstoffs wird einzig N.N′-Di-neopentyl-formamidin (19) erhalten. Eigenschaften und Reaktionen der Thioharnstoff-S-dioxide werden mit denen der Pyridinsulfinsäuren verglichen.
    Additional Material: 1 Ill.
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  • 82
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    Weinheim : Wiley-Blackwell
    Liebigs Annalen 722 (1969), S. 132-141 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cycloaddition Reactions with α,β-Diheterosubstituted Olefins, I. Reactions with Sulfonyl IsocyanatesThe reaction of sulfonyl isocyanates with α,β-dialkoxy substituted olefins yields N-sulfonyl-3,4-dialkoxy-2-azetidinon compounds 3 as main products and N-sulfonylcarboxylamide compounds 4. Kinetic studies on the formation of β-lactams 3 are reported and the reactions of these compounds with methanol are described. The formation of β-lactams from α,β-sulfur and nitrogen substituted olefins can be detected by i.r.spectroscopy.
    Notes: Sulfonylisocyanate reagieren mit α.β-disauerstoffsubstituierten Olefinen unter 1.2-Addition zu 1-Sulfonyl-3.4-dialkoxy-azetidinon-(2)-Verbindungen 3. Daneben bilden sich durch Substitution α.β-ungesättigte N-Sulfonyl-carbonsäureamid-Verbindungen 4. Mit Schwefel-und Stickstoff-substituierten Olefinen wird eine Azetidinon-Bildung IR-spektroskopisch nachgewiesen. Reaktionsweisen sowie kinetische Untersuchungen zur Bildung der β-Lactam-Derivate 3 werden beschrieben.
    Additional Material: 7 Tab.
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  • 83
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions with Organophosphorus Compounds, XXIII1). A New Synthesis of Tetrazoles and Iminonitriles from N- Substituted IminophosphoranesA generally applicable synthesis of 1-R1-5-R2-substituted tetrazoles by reaction of the corresponding triphenyliminophosphoranes (C6H5)P=NR1 with acid chlorides R2COCl and NaN3 is reported. The same phosphoranes react with acyl cyanides R2COCN to form the iminonitriles R2C(CN)=NR1.
    Notes: Es wird über eine allgemein anwendbare Synthese von 1-R1-5-R2-substituierten Tetrazolen durch Umsetzung von Triphenyliminophosphoranen (C6H5)3P=NR1 (R1=Alkyl, Aryl) mit Säurechloriden R2COCl (R2=Alkyl, Alkenyl) und NaN3 berichtet. Triphenyliminophosphorane lassen sich mit Säurecyaniden R2COCN zu Iminonitrilen R2C(CN)=NR1 umsetzen.
    Additional Material: 1 Tab.
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  • 84
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    Weinheim : Wiley-Blackwell
    Liebigs Annalen 725 (1969), S. 73-86 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Ketene Derivatives, XVI1). Electrophilic Substitution of Simple Ketene S,N-AcetalsSimple ketene S,N-acetals [R-CH=C(SCH3)NR′ 2; R=Horalkyl] react with electrophiles such as acid chlorides, activated vinyl chlorides, ketene mercaptals, ethoxymethylene sulfonic acid amides, dinitrofluorobenzene, trichloro-s-triazine and o-nitrobenzenesulfenyl chloride to give β-substituted ketene S,N-acetals. In some cases products of secondary reactions are isolated; acid chlorides, for instance, sometimes give substituted β-acyloxyacrylic acid thioamides.
    Notes: Einfache Keten-S.N-acetale [R-CH=C(SCH3)NR′2; R=H oder Alkyl] reagieren mit Elektrophilen - z. B. mit Säurechloriden (zu 4), aktivierten Vinylchloriden (zu 12), Ketenmercaptalen (zu 14), Äthoxymethylensulfonamiden (zu 22, 23), Dinitrofluorbenzol (zu 19), Cyanurchlorid (zu 18) und o-Nitro-benzolsulfensäurechlorid (zu 20, 21) - zu β-substituierten Keten-S.N-acetalen. In einigen Fällen isoliert man Produkte von Folgereaktionen; mit Säurechloriden erhält man z. T. substituierte β-Acyloxy-acrylsäurethioamide (z. B. 8).
    Additional Material: 13 Tab.
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  • 85
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Fragmentation Reactions of Carbonyl Compounds with Electronegative β-Substituents, XV1). On the Reaction of Electronegatively β-Substituted Pivalic Acid EstersReaction of triiodo- (2) and tritosyloxy pivalic acid ester 3a, with sodium ethanolate affords 3-ethoxy-2-ethoxymethyl-1-propene (5) and diethyl carbonate (6) by a fragmentation reaction; on the other hand yields the tribromo pivalic acid ester 1b by neopentyl substitution 7a and b. Substitution of the monosubstituted pivalic acid esters 4a-d leads to the formation of 9, by products being formed at the same time. - Reaction of ethyl tosyloxypivalate (4b) with lithium organic compounds gives tetrasubstituted oxetanes 14.
    Notes: Trijod- (2) und Tritosyloxy-pivalinsäureester 3a liefern mit Na-äthylat 3-Äthoxy-2-äthoxymethyl-propen-(1) (5) und Kohlensäurediäthylester (6). Der Tribrom-pivalinsäureester 1b ergibt durch Neopentyl-Substitution 7a und b. Die monosubstituierten Pivalinsäureester 4a-d werden zu Methoxy-pivalinsäure-methylester (9) substituiert, wobei Nebenprodukte entstehen. - Umsetzung von Tosyloxy-privalinsäure-äthylester (4b) mit Lithiumorganylen ergibt die tetrasubstituierten Oxetane 14.
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  • 86
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    Weinheim : Wiley-Blackwell
    Liebigs Annalen 725 (1969), S. 154-166 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Preparation of Analogs of Dehydroabietylamine and Dehydroabietylguanidine by Total SynthesisAnalogs of racemic dehydroabietylamine and homodehydroabietylamine have been synthesized. The isopropyl group is replaced by hydrogen, or by a methyl or methoxy group. The guanidinium salts are prepared from the corresponding amines. Further variations include the additional introduction of a hydroxy group and substitution of the amino or guanidinium group by a quaternary ammonium or isothiouronium group.
    Notes: Es werden Analoge 2 des racemischen Dehydroabietylamins und Homodehydroabietylamins dargestellt. Dabei wird die Isopropyl-Gruppe durch Wasserstoff, eine Methyl- oder eine Methoxy-Gruppe ersetzt. Aus den Aminen werden die entsprechenden Guanidinium-Salze dargestellt. Weitere Variationen erstrecken sich auf die zusätzliche Einführung einer Hydroxy-Gruppe und Ersatz der Amino- bzw. Guanidinium-Gruppe durch eine quartäre Ammonium-oder Isothiuronium-Gruppe.
    Additional Material: 7 Tab.
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  • 87
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions with Diazocarbonyl Compounds, XXXII1). Synthesis of 2-Carboxy-5-hydroxytryptamine and Pyridazine Derivatives. Japp-Klingemann-Synthesis with p-Hydroxy-phenyl-diazonium Salts or p-Chinon-diazides, respectivelyp-Hydroxybenzenediazoniumchloride (1) and 2,6-dichloro-1,4-benzoquinone-4-diazide (2) react with 3-ethoxycarbonyl-2-piperidone (3) and with ethyl 2-acetyl-4-cyanobutyrate (10) (Japp-Klingemann synthesis) to give 4-hydroxyphenylhydrazones 6, 7 nad 11, 12 respectively. The hydrazones 6 and 7 are converted into the 5-hydroxyindole dervatives 8 and 9 (E. Fischer indole synthesis), while the hydrazone 12 is cyclized to the tetrahydropyridazine derivatives 13 and 14.
    Notes: p-Hydroxy-benzoldiaziniumchlorid (1) und 2.6-Dichlor-benzochinon-(1.4)-diazid-(4) (2) werden mit 3-Äthoxycarbonyl-piperidon-(2) (3) und mit 2-Acetyl-4-cyan-buttersäureäthylester (10) nach Japp und Klingemann zu den 4-Hydroxy-phenylhydrazonen 6 und 7 bzw. 11 und 12 umgesetzt. Die Hydrazone 6 und 7 lassen sich nach E. Fischer in die 5-Hydroxy-indol-Derivate 8 und 9 überführen, während das Hydrazon 12 zu den Tetrahydropyridazin Derivaten 13 und 14 cyclisiert.
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  • 88
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    Weinheim : Wiley-Blackwell
    Liebigs Annalen 726 (1969), S. 125-135 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Triterpenes XXVIII1). The Saponins of Spinach (Spinacia oleracea L.)Two saponins, spinasaponin A and B, have been isolated from the roots of spinach. The structures are elucidated by acid and enzymatic hydrolysis and by methylation, fission of the resulting methyl derivatives, and identification of the methyl sugars. Accordingly, spinasaponin A is 3O-[β-D-Glucopyranosyl(1 → 3)-β-D-glucuronopyranosyl]-3β-hydroxy-Δ12-oleanen-28-acid (1a), whereas B is the corresponding derivative 2a of hederagenin.
    Notes: Aus den Wurzeln des Spinats werden zwei Saponine, Spinasaponin A und B, isoliert, deren Struktur durch saure und enzymatische Hydrolyse sowie durch Methylierung, Spaltung der Methyl-Derivate und Identifizierung der methylierten Zucker ermittelt wird. Spinasaponin A ist demnach eine 3O-[β-D-Glucopyranosyl(1 → 3)-β-D-glucuronopyranosyl-(1)]-3β-hydroxy-Δ12-oleanen-28-säure (1a), während B das entsprechende Hederagenin-Derivat 2a ist.
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  • 89
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Preparation of 6α-Fluoro-11β, 21 -dihydroxy-l6α-methyl-l,4-pregnadiene-3,20-dione (Fluocortolone) via Substrate-Structure- Directed Specific 11β- Hydroxylation by Curvularia lunataThe formation of the by-products 14 and 13, with 9α- and 14α-hydroxy groups, in the 11β-hydroxylation of 6α-fluoro-21-hydroxy-16α-methyl-4-pregnene-3,20-dione (9b) with Curvularia lunata is inhibited by using a similar substrate with 5α-bromo-substituent by sterical shielding of the α-side. A subsequent route for the synthesis of 6α-fluoro-11β,21-dihydroxy-16α-methyl-1,4-pregnadiene-3,20-dione (15) is described.
    Notes: Die bei der 11β-Hydroxylierung von 6α-Fluor-21-hydroxy-16α-methyl-4-pregnen-3.20-dion (9b) mit Curvularia lunata entstehenden Nebenprodukte 14 und 13 mit 9α- und 14α-Hydroxy-Funktion treten bei Einsatz der 5α-Brom-substituierten Vorstufe 5 durch sterische Abschirmung der α-Seite nicht auf. Der weitere Synthesegang zu 6α-Fluor-11β.21-dihydroxy-16α-methyl-1.4-pregnadien-3.20-dion (15, Fluocortolon) wird beschrieben.
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  • 90
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    Weinheim : Wiley-Blackwell
    Liebigs Annalen 726 (1969), S. 216-218 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Syntheses and Properties of the Nine Isomeric Tolyl ToluatesThe title compounds 5-7 (a-c) are prepared and analyzed for their chemical and spectroscopical properties.
    Notes: Die Titelverbindungen 5-7 (a-c) werden hergestellt und ihre chemischen und spektroskopischen Eigenschaften untersucht.
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  • 91
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    Weinheim : Wiley-Blackwell
    Liebigs Annalen 727 (1969), S. 22-34 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reaction of Thioamides with Sulfenyl ChloridesSulfenyl chlorides react with secondary thioamides to give iminomethyl disulfides 2. The sulfur atom is attacked by the sulfenyl chloride, even when the thioamide system is substituted by electron-withdrawing groups. Asymmetric iminomethyl disulfides obtained from the reaction of primary thioamides and sulfenyl chlorides decompose very easily, and in general they have been isolated as salts. In only one case has a neutral iminomethyl disulfide (23) been isolated. Thiobenzamide condenses with chlorocarbonyl sulfur chloride (21) to give 5-phenyl-1,2,4-dithiazol-3-one (28), whereas condensation with phenylimino-chloromethane sulfenyl chloride (20) leads to the corresponding dithiazole derivative 25, but only in small amounts.
    Notes: Durch Umsetzung von sekundären Thioamiden mit Sulfenylchloriden entstehen Iminomethyldisulfide 2. Der elektrophile Angriff des Sulfenylchlorids erfolgt auch dann am Thion-Schwefel, wenn das Thioamid-System elektronenziehende Substituenten trägt. Asymmetrische Iminomethyldisulfide aus primären Thioamiden und Sulfenylchloriden sind besonders leicht zersetzlich und nur als Salze isoliert worden. Nur in einem speziellen Fall wird ein neutrales Iminomethyldisulfid (23) aus einem primären Thioamid erhalten. Thiobenzamid reagiert mit Chlorcabonylschwefelchlorid (21) unter Ringschluß zu 5-Phenyl-1.2.4-dithiazolon-(3) (28). Bei Umsetzung mit Phenylimino-chlormethansulfenylchlorid (20) weicht die Reaktion aus, und das entsprechende Dithiazol-Derivat 25 wird nur in geringem Maße gebildet.
    Additional Material: 4 Tab.
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  • 92
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    Weinheim : Wiley-Blackwell
    Liebigs Annalen 727 (1969), S. 61-70 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On the Structure of Thioamides and their Derivatives, Vl 1). Magnetic Anisotropy of the Thio-amide GroupModels of the magnetic anisotropy of the thioformamide and the thioacetamide system are developed with the aid of sterically fixed 1-thioacyl piperidines. In this way the different assignment of the signals of the cis- and trans-N-methyl groups in dimethylthioacetamide and dimethylthioformamide (2a) can be explained. The steric effects of the acid residue on the shielding conditions are discussed on the basis of the n.m.r. spectra of 1-thioisobutyryl- and 1-thiopivalyl-4-methylpiperidine (1c and d). In 1d and in N.N-dimethylthiopivalinamide (2d) rotation around the C-N bond is fast at room temperature. The 2-methyl group in 1-thioacetyl-2-methylpiperidine (1f) is axial.
    Notes: Mit Hilfe von sterisch fixierten 1-Thioacyl-piperidinen werden Modelle für die magnetische Anisotropie-Wirkung des Thioformamid- und Thioacetamid-Systems entwickelt, die die unterschiedliche Zuordnung der Signale der cis- und trans-N-Methyl-Gruppe beim Dimethylthioacetamid und Dimethylthioformamid (2a) erklären. Anhand der NMR-Spektren von 1-Thioisobutyryl- und 1-Thiopivalyl-4-methyl-piperidin (1c und d) wird der sterische Einfluß des Säurerestes auf die Abschirmverhältnisse diskutiert. 1d sowie das N.N-Dimethyl-thiopivalinsäureamid (2d) zeigen bei Raumtemperatur schnelle Rotation um die C-N-Bindung. - Die 2-Methyl-Gruppe des 1-Thioacetyl-2-methyl-piperidins (1f) ist axial angeordnet.
    Additional Material: 1 Ill.
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  • 93
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The absolute oil of cassie (Acacia farnesiana WILLD.) has been thoroughly investigated by using several combined chromatographic techniques. Among the 38 new constituents which were thus identified in this oil, four deserve a particular mention, namely, the cis-3-methyldec-3-en-1-ol (I), the related acid III, the trans-3-methyl-dec-4-enoic acid (IV), and the homoterpene lactone dihydroactinidiolide (II). With the exception of the last one, these unusual C11 compounds play a prominent role in the characteristic fragrance of cassie oil.
    Additional Material: 2 Ill.
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  • 94
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    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 52 (1969), S. 69-76 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The three ternary limiting isotherms of the system KCI-RbCI-CsCI-H2O are given for 25°. The system KCI-RbCI-H2O, with only one solid phase present, belongs to the type I of the ROOZEBOOM classification. A large miscibility gap is present in the systems RbCI-CsCI-H2O and KCI-CsCI-H2O; in the latter the incorporation is almost negligible; they belong to ROOZEBOOM's type IV.
    Additional Material: 5 Ill.
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  • 95
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A new chemical degradation of (-)-kopsine is described which completely confirms the structure of this alkaloid. Correlation of (-)-aspidofractinine, (-)-pleiocarpine and (-)-kopsine with (-)-minovincine establishes the absolute stereochemistry of these bases. It appears that, in contrast to the aspidospermine group, all alkaloids containing the aspidofractinine skeleton possess the same absolute stereochemistry.
    Additional Material: 2 Ill.
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  • 96
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The 13C NMR. spectra of seventeen m- and p- subsituted benzonitriles were examined and partially anlayzed. The C-1 carbon shieldings can be expressed in terms of a linear correlation with the LCAO-MO-π-electron density at C-1. No such correlation was found for the cyanocarbon, whose electron density shows only slight varriations for the different substitutents. This fact is consistent with the relatively small range of the chemical shifts at this center.
    Additional Material: 1 Ill.
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  • 97
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    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 52 (1969), S. 107-121 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wird über Darstellung und spektroskopische Untersuchungen von Kupfer (II)-Komplexen CuL2X2 und CuL4X2 mit grösstenteils unidentaten Stickstoffbasen berichtet. Durch Ausnützung der Einflüsse von Substitutenten am Pyridin- bzw. Piperidinring der Liganden L wurden Komplexe verschiedener Stereometrie erhalten, an denen sich der Zusammenhang zwischen Mikrosymmetrie und Elektronenspektren studieren liess. Insbesondere konnte die Stauchung eines pseudotetraedrischen Teilchens über eine Reihe von Zwischenstufen bis zur planaren Anordnung der 4 Ligandatome anhand einer Anzahl von Verbindungen des Type CuL2X2 verfolgt werden. Die Arbeit befasst sich dabei im wesentlichen mit den Ligandenfeldspektren (über die Elektronentransfer-Übergange sol1 später berichtet werden). Der letzte Ligandenfeldübergang tritt bei den planaren Komplexen - offenbar wegen. Abschirmung des Zentral-Ions vor Störungen längs der z-achse bei unerwartet hoher Energie auf.
    Additional Material: 4 Ill.
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  • 98
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of the di- and trimerization of ethylen in organic solvents under the influence of a homogeneous catalyst containing π-tetramethylcyclobutadiene-nickeldichloride and a prereacted mixture of ethylaluminiumdichloride and tri-n-butylphosphine are reported. The primary reaction product is 1-butene, which is isomerized to 2-butene (cis/trans) during the reaction. The C6-Olefins are formed by the reaction of ethylene with 1-butene and with the 2-butenes. The following primary reaction products are obtained: 3-hexene (cis/trans), 1-hexene, 2-ethyl-1-butene, 3-methyl-1-pentene and 3-methyl-2-pentene (cis/trans).The effect of other phosphines on the reaction was also studied. The relative composition of the reaction product is strongly dependent upon the amount and the LEWIS base strength of the phosphine present. The results are in accordance with a coordinative mechanism on nickel.
    Additional Material: 5 Ill.
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  • 99
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of the condimerization of ethylene and propene in organic solvents under the influence of a homogeneous catalyst containing π-tetramethylcyclobutadiene-nickeldichloride and a prereacted mixture of ethylaluminiumdichloride and tri-n-butylphosphine are reported. The primary reaction products are: 1-pentene, 2-pentene (cis/trans), 2-methyl-1-butene and 3-methyl-1-butene.The effect of other phosphines was also studied. The activity as well as the selectivity of the catalyst are strongly dependent upon the amount and the LEWIS base strength of the phosphine present.The results are in accordance with a coordinative mechanism on nickel.
    Additional Material: 3 Ill.
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  • 100
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Hydrazinoethyl phosphoric monoester has been prepared by reacting hydrazinoethanol with polyphosphoric acid, and isolated as di-sodium salt.Sodium hydrazinoethyl phosphate reacts with phenylisothiocyanate (in H2O+ethanol) to yield mainly the derivative thiocarbamoylated at the substituted nitrogen atom. This derivative, heated for one night at 100° in 0.5 N HCl, is cyclized to 3-amino-2-phenylimino-thiazolidine in 62% yield. Sodium hydrazinoethyl phosphate reacts with o-methoxycarbonylphenyl isothiocyanate (in H2O+dioxane) at the unsubstituted nitrogen atom to yield mainly the corresponding quinazoline derivative (IV, X = OPO3Na2). This derivative, heated for one night at 100° in 0.5 N HCl, is cyclized to 2-o-carboxyphenylamino-dihydro-δ2-1, 3, 4-thiadiazine (Va) in 55% yield (hydrolysis of the lactamic function as well).Aminoethyl phosphorous monoester (colaminephosphorous acid) reacted with phenylisocyanate (in H20+dioxane) in slightly alkaline medium (one equivalent of NaOH) yields sodium N-phenylcarbamoylaminoethyl phosphite. Refluxed for 20 minutes in 1N NaOH, this carbamoyl derivative is not cyclized but only hydrolyzed to the open-chained N-phenyl-N′-hydroxyethylurea (VII).
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