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  • 2020-2023
  • 1965-1969  (1,194)
  • 1920-1924
  • 1968  (557)
  • 1967  (637)
  • Organic Chemistry  (1,180)
  • Calcium  (14)
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 2 (1968), S. 296-298 
    ISSN: 1432-0827
    Keywords: Calcium ; Lipid ; Bacteria ; Calcification
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé On a fait ce travail pour determiner si le facteur responsable pour la liaison de calcium par un calcifableBacterionema matruchotii est dans la fraction lipide de la cellule. Des cellules congelees et sechees ont ete extraites par le chloroform-methanol. La fraction de chloroform-methanol, les cellules extraites et les cellules non traitees ont ete examinees pour la liaison de calcium. La fraction du chloroform-methanol et les cellules non traitees avaient la liaison de calcium. Les cellules extraites n'en avaient pas.
    Abstract: Zusammenfassung Diese Arbeit wurde durchgeführt um festzustellen, ob sich der Faktor für die Calcium-bindung, durch das calcifizierendeBacterionema matruchotii, in der Lipoidfraktion befindet. Die lyophiilisierten Zellen wurden mit Chloroform-Methanol extrahiert. Die Chloroform-Methanol-Fraktion, die extrahierten Zellen, sowie die nicht behandelten Zellen wurden auf eine Calciumbindung hin untersucht. Die Chloroform-Methanol-Fraktion und die nicht behandelten Zellen demonstrierten eine Calciumbindung. Die extrahierten Zellen hingegen nicht.
    Notes: Abstract This work was done to determine whether the factor responsible for calcium binding by a calcifiableBacterionema matruchotii is in the lipid fraction of the cell. Freeze-dried cells were extracted with chloroform-methanol. The chloroform-methanol fraction, the extracted cells and untreated cells were examined for calcium binding. The chloroform-methanol fraction and the untreated cells bound calcium. The extracted cells did not.
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 2 (1968), S. 67-76 
    ISSN: 1432-0827
    Keywords: Calcergy ; Calciphylaxis ; Calcium ; Metals
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Chez le rat, des expériences ont montré que, sauf de rares exceptions, les calcifications produites au site d'injection d'acétate de plomb, de chlorure de cérium, chlorure de calcium ou de permanganate de potassium sont complètement prévenues ou fortement inhibées par l'application locale simultanée de provocateurs calciphylactiques, mais non par des agents non provocateurs. Malgré quelques exceptions (attribuées à des interrelations chimiques spécifiques entre certaines des substances utilisées), cette curieuse corrélation entre l'efficacité calciphylactique provocatrice et le pouvoir anticalcergique est, d'après le test χ2, hautement significative (P〈0,001).
    Abstract: Zusammenfassung Nach subcutaner Injektion von Bleiacetat, Ceriumchlorid, Calciumchlorid oder Kaliumpermanganat tritt an der Injektionsstelle eine starke Verkalkung auf. Bis auf sehr wenige Ausnahmen kann diese durch gleichzeitige lokale Anwendung von calciphylaktischen Provokatoren verhütet oder weitgehend unterdrückt werden. In dieser Beziehung sind nicht provolatorisch wirkende Stoffe inaktiv. Trotz der wenigen Ausnahmen (die wahrscheinlich auf spezifische, chemische Wechselwirkungen zwischen manchen der untersuchten Substanzen beruhen) ist dieser merkwürdige Zusammenhang zwischen calciphylaktisch provozierender und anticalcergischer Aktivität, nach dem χ2-Test berechnet, statistisch hochsignifikant (P〈0,001).
    Notes: Abstract Experiments on rats indicate that, with very few exceptions, the calcification which occurs at subcutaneous sites of treatment with lead acetate, cerium chloride, calcium chloride or potassium permanganate is completely blocked or severely inhibited by simultaneous topical application of calciphylactic challengers but not of non-challengers. Despite the few exceptions (which are thought to depend upon specific chemical interactions between some of the compounds tested) this singular correlation between calciphylactic challenging and anticalcergic potency, is highly significant by the Chi-square-test (P〈0.001).
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 2 (1968), S. 253-261 
    ISSN: 1432-0827
    Keywords: Calcium ; Ion ; Binding ; Chondroitin ; Cartilage
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé La liaison du calcium par le sulfate de chondroitin C a été étudiée en utilisant des méthodes biologiques et physicochimiques pour la détermination quantitative du calcium ionique. Les valeurs moyennes pour logK j, le logarithme de la constante de formation non corrigée d'un complexe calcium-sulfate de chondroitin C, sont 1,64 par la technique de cœur de grenouille, 1,55 par la méthode de murexide, 1,39 par l'ultrafiltration et 1,04 par l'électrode sélective du calcium. L'ordre de grandeur de ces valeurs suggèrent que le sulfate de chondroitin C a une capacité de liaison pour calcium relativement élevée, mais les valeurs calculées pour un paramètre d'échangeK p indiquent que le calcium a une affinité faible pour le polysaccharide.
    Abstract: Zusammenfassung Die Bindung von Calcium mit Chondroitinsulfat C wurde untersucht mittels biologischer und physikalisch-chemischer Methoden für die quantitative Bestimmung des ionischen Calciums. Im Durchschnitt ergab logK j, der Logarithmus der unkorrigierten Formationskonstante für einen Calciumchondroitinsulfatkomplex, 1,64 mit der Technik des Froschherzens, 1,55 mit der Murexidmethode, 1,39 mittels Ultrafiltration und 1,04 mit den Calciumselektiven Elektroden. Die Größe dieser Werte zeigt, daß Chondroitinsulfat eine relativ hohe Bindungskapazität für Calcium hat, die berechneten Werte für einen AustauschparameterK p jedoch, daß Calcium eine kleine Affinität für Polysaccharide hat.
    Notes: Abstract The binding of calcium by chondroitin sulfate C was studied by employing biological and physicochemical methods for the quantitative determination of ionic calcium. Mean values for logK j, the logarithm of the uncorrected formation constant for a calcium-chondroitin sulfate complex, were 1.64 with the frog heart technique, 1.55 with the murexide method, 1.39 with ultrafiltration and 1.04 with the calcium selective electrode. The magnitude of these values suggests that chondroitin sulfate has a relatively high binding capacity for calcium, but calculated values for an exchange parameterK p indicate that calcium has a low affinity for the polysaccharide.
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 2 (1968), S. 301-313 
    ISSN: 1432-0827
    Keywords: Calcium ; Absorption ; Vitamin D
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 2 (1968), S. 20-29 
    ISSN: 1432-0827
    Keywords: Bone Atrophy ; Bone Resorption ; Calcium ; Collagen ; Osteoporosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Atrophie osseuse d'immobilisation était induite par section de la plexus brachial et/ou désarticulation de la coude. Après 9 bis 12 semaines de désuétude huméri intactes furent examinés par rayons X et leur qualités physiques déterminés. Les humérientiers furent isolés, dégraissés, desséchés au poids constant, et leur teneur en cendre d'os et collagène déterminés. Huit des 10 huméri immobilisés monstrérent radiodensité diminué. La jambe inusitée monstra perte parallèle en poids sec et poids sans gras (−23.2%), en collagène (−25.3%), et en cendre d'os (−26.1%) en comparaison de la jambe normale. Les données monstrèrent que la portion plus grande du tissu osseux perdu en atrophie osseuse d'immobilisation est remplacée par de l'eau, du gras, et des autres matériels organiques inconnus plutôt que par tissu fibreux, et que collagène est perdu en proportion du minéral. La perte proportionellement plus grande du collagène et de la cendre d'os que du poids sec et poids san gras semble dû à une augmentation du matériel organique, non-collagéne, non-lipide, kprobablement protéine.
    Abstract: Zusammenfassung Immobilisations-Knochenatrophie wurde in 10 erwachsenen Hunden herbeigeführt durch Brachialplexusschnitt und/oder Ellenbogenexartikulation. Nach 9–12 Wochen der Immobilisation wurden die intakten Humeri unter Röntgenstrahlen untersucht und ihre physischen Eigenschaften bestimmt. Derintakte Humerus wurde isoliert, entfettet, zu konstantem Gewicht getrocknet und der Knochenaschengehalt und Kollagengehalt bestimmt. Acht der 10 experimentellen (immobilisierten) Humeri demonstrierte Beweis von verringerter Röntgendichte. Die immobilisierte Extremität zeigte ähnlichen Verlust in trockenem, fettfreiem Gewicht (−23,2%) in Kollagen (−25.3%) und Knochenasche (−26,1%) im Vergleich zur normalen Extremität. Die Date deuten an, daß der Hauptanteil des Verlustes des Knochengewebes (bei Immobilisations-Knochenatrophie) von Wasser, Fett und anderen unidentifizierten organischen Substanzen ersetzt wird, als von Faserngewebe und daß Kollagen und Knochenasche im gleichen Verhältnis verloren gehen. Der größere, proportionale Verlust an Kollagen und Knochenasche, eher als der Verlust an fettfreiem Gewicht, scheint in der Zunahme an nicht kollagener, nicht lipoider, organischer Substanz, vermutlich Protein, zu liegen.
    Notes: Abstract Disuse bone atrophy was induced in 10 adult dogs by means of brachial plexus section and/or elbow disarticulation. After 9 to 12 weeks of disuse intact humeri were examined by X-ray, and their physical properties determined. Thewhole humeri were isolated, defatted, dried to constant weight, and their mineral and collagen content determined. Eight out of 10 experimental (non-used) humeri demonstrated evidence of decreased radiodensity. The non-used limb demonstrated parallel loss in dry, fat-free weight (−23.2%), in collagen (−25.3%), and in mineral (−26.1%), as compared to the normal limb. The data indicated that the major portion of the lost bone tissue in disuse osteoporosis is replaced by water, fat, and other unidentified organic materials rather than fibrous tissue, and that collagen is lost in equal proportion to mineral. The proportionatelly greater loss of collagen and mineral than of dry, fat-free weight appears to be due to an increase of non-collagenous, non-lipid organic material, presumably protein.
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Pflügers Archiv 300 (1968), S. 23-34 
    ISSN: 1432-2013
    Keywords: Electro-Physiology ; Ranvier-Node ; Stationary Current-Voltage Relation ; Calcium ; Elektrophysiologie ; Ranvierscher Schnürring ; Stationäre Strom-Spannungscharakteristik ; Calcium
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Erhöht man die extracelluläre Calcium-Konzentration, so verschieben sich die Stromextrema der Strom-Spannungsbeziehung des Ranvier-Knotens nach Depolarisationsrichtung. Mit Hilfe einer Gleichung zur Darstellung der Kennlinien läßt sich diese Wirkung durch Änderung eines einzigen Parameters V Tγ beschreiben. Dieser gibt die Spannungslage des Abfalles einer Stufenfunktion wieder, die im Rahmen der Ionentheorie der Kaliumleitfähigkeitsvariablen n ∞ 4 (V) entspricht. Durch Erhöhung von [Ca··] a wird V Tγ nach Depolarisationsrichtung verschoben. Darüber hinaus konnte eine deutliche Abhängigkeit dieses Parameters von [K·] a festgestellt werden. Der Calcium-Einfluß auf das Membranpotential konnte als Konsequenz der Vt r −-Verschiebung interpretiert werden.
    Notes: Summary An increase of the extracellular calcium-concentration shifts the extreme current values of the current-voltage-relation of a Ranvier-node towards depolarization. This influence can be described by the change of one single parameter V Tγ of an equation representing the current-voltage-characteristic. V Tγ referres to the potential at which the s-shaped step-function of resistance change assumes the arithmetical mean of its limiting values. The step-function compares to the variable of potassium conductance n ∞ 4 (V). An increase of [Ca··] a shifts V Tγ towards depolarizing potentials. V Tγ is also found to depend on [K·] a . The influence of calcium on membrane potential is interpreted as a consequence of the observed shift of V Tγ .
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 260 (1968), S. 444-455 
    ISSN: 1432-1912
    Keywords: Chlorpromazin ; Calcium ; Zellmembran ; Muskelproteine ; Chlorpromazine ; Calcium ; Cell Membrane ; Muscle Proteins
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary 1. The calcium induced increase in ATPase and the rate of calcium uptake of the vesicular fragments of sarcoplasmic reticulum isolated from rabbit skeletal muscle are reduced by reserpine, prenylamine, chlorpromazine and imipramine. 3×10−5M reserpine, prenylamine, chlorpromazine and ∼3×10−4M imipramine are required to produce 50% inhibition of both activities. 2. In the presence of the drugs the rate of calcium exchange at the cessation of calcium uptake is reduced to the same extent as the initial rate of calcium uptake. 3. Neither the calcium storing capacity nor the ability to concentrate calcium are impaired by the drugs. 4. The drugs do not affect the calcium dependent phosphate exchange between ATP and ADP and the calcium dependent formation of phosphoprotein.
    Notes: Zusammenfassung 1. Reserpin, Prenylamin, Chlorpromazin und Imipramin hemmen sowohl die Geschwindigkeit der Calcium-Aufnahme als auch die der Calcium-induzierten Extra-ATP-Spaltung an isolierten Vesikelmembranen des sarkoplasmatischen Reticulums von quergestreifter Muskulatur des Kaninchens. Die für eine 50%ige Hemmung erforderlichen Konzentrationen betragen beim Reserpin, Prenylamin und Chlorpromazin 3×10−5M, beim Impiramin ∼3×10−4M. 2. Calcium-Efflux und -Influx werden durch die Pharmaka in gleichem Ausmaß gehemmt. 3. Das Konzentrationsvermögen der Vesikel für Calcium wird deshalb durch die Hemmstoffe nicht beeinflußt. 4. Der erste Reaktionsschritt des aktiven Calciumtransports der Vesikel — die Übertragung des Phosphates des ATP auf das Vesikelprotein — wird durch die Pharmaka nicht beeinflußt.
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 260 (1968), S. 298-308 
    ISSN: 1432-1912
    Keywords: Anesthetics, Local ; Adrenal Medulla ; Calcium ; Catecholamines
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Local anesthetics (LA's) were examined for their ability to inhibit medullary catecholamine release from perfused cat adrenal glands in response to calcium (0.5 mM) in the presence of 56 mM KCl. LA's which are esters of p-aminobenzoic acid (including benzocaine), or which possess either an amide group (dibucaine), an amidine group (phenacaine), or an amino alkyl ether linkage (diphenhydramine) all produced a graded inhibition of the action of calcium, which was reversed by excess calcium (3 mM). Benzocaine, which does not possess an alkyl amino nitrogen, was five times more potent than procaine in depressing calciumevoked secretion; benoxinate, as well as tetracaine, which differ from procaine and its dimethyl analogue by possessing substituent groups on the aromatic ring were over thirty times more potent than procaine and dimethyl-procaine. Increasing the pH of the perfusion medium from 7.0–8.3 produced no marked alteration in the ability of procaine, tetracaine, and benzocaine to inhibit the stimulant actions of calcium. It is concluded that the aromatic ring of the LA molecule is more important than the alkyl nitrogen in determining the activity of a given agent in blocking the action of calcium.
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  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 260 (1968), S. 342-365 
    ISSN: 1432-1912
    Keywords: Myocardium ; Frequency of Contraction ; Action Potential ; Calcium ; Excitation-Contraction Coupling ; Myokard ; Kontraktionsfrequenz ; Aktionspotential ; Calcium ; Elektromechanische Kopplung
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The influence of stimulation frequency on the course of the transmembrane action potential (AP) and on the isometric tension of isolated guinea pig papillary muscles has been investigated. Special attention has been paid to the question whether the observed changes can be due to a frequency dependent increase of the extracellular concentration of Ca2+ and K+. The following results have been obtained: 1. The amplitude of the AP decreases at a stimulation frequency above 2/sec due to a diminished membrane-resting-potential (MRP) and a decrease in overshoot. 2. The duration of the AP is influenced biphasically by increasing the stimulation frequency at relatively low external calcium concentrations (1.2 and 2.4 mM). When the frequency of stimulation is increased, starting at 0.125/sec, the AP duration is prolonged at first and then shortened. At frequencies below 0.125/sec (down to 0.004/sec) the AP duration again increases. The prolongation of the AP in the medium frequency range (between 0.125 and 0.5/sec) is minimal at a higher calcium concentration (4.8 mM). The marked shortening of the AP duration caused by an increase in stimulation frequency above 1/sec corresponds to the frequency dependent increase in isometric tension of the papillary muscle. 3. The AP duration is shortened by 70 msec when the stimulation frequency is raised from 1/sec to 5/sec. After switching back to the lower frequency (1/sec) the disappearance of the frequency effect on the duration of the AP starts with a lower and continues with a higher speed than that on the force of contraction, the original values of both parameters being reached at the same time. 4. The extent of the frequency induced change of the AP duration is almost equal at 30%, 60% and 90% repolarisation. Consequently, the duration of the “plateau” (at 30% repolarisation) is shortened relatively more than the AP duration at 90% repolarisation. 5. The AP duration at 90% repolarisation is influenced by Ca2+ and Na+ antagonistically according to the relation [Ca2+]/[Na+]2 in the frequency range between 0.125/sec and 4.0/sec. In contrast, the extent of the shortening of the “relative duration of the plateau” depends on the external sodium concentration ([Na+] e ). The lesser shortening of the “relative duration of the plateau” at a decreased [Na+] e (70 mM instead of 140 mM) corresponds to a decreased positive inotropic frequency effect. 6. The MRP is decreased by 8 mV when the stimulation frequency is increased from 1/sec to 5/sec. Considering the relation between MRP and [K+] e at a stimulation frequency of 1/sec a frequency induced increase of [K+] e from 5.9 mM to 8–9 mM can be assumed. Such an increase in [K+] e , however, only causes a shortening of the AP duration by 6 msec. Concomitantly, the relative duration of the plateau is prolonged. 7. The shortening of the AP duration of about 70 msec due to an increase of the stimulation frequency from 1/sec to 5/sec equals—as does the augmentation of the contractile force of the muscle—the effect of a two—or threefold elevation of the external calcium concentration. Similarly the lengthening of the AP duration by an increase in stimulation frequency from 0.125 to 0.5/sec at a relatively low external calcium concentration (1.2 mM) equals the effect of raising the [Ca2+] e . 8. The results lead to the conclusion that the influence of the frequency of stimulation on the duration of the action potential is caused mainly by an increase of the calcium concentration at the outside of the cell membrane while the decrease of the membrane-resting-potential as well as of the overshoot may be the result of an extracellular accumulation of K+.
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  • 10
    ISSN: 1432-1912
    Keywords: Chlorpromazin ; Calcium ; Zellmembran ; Muskelproteine ; Lipide ; Chlorpromazine ; Calcium ; Cell Membrane ; Muscle Protein ; Lipids
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary 1. Reserpine, chlorpromazine, prenylamine and imipramine are bound to vesicles isolated from the sarcoplasmic reticulum of rabbit striated muscle cells as well as by the lipids which can be extracted from the vesicular preparations. 2. At concentrations of 5×10−7 M reserpine, chlorpromazine and prenylamine, drug binding can just be detected. At drug concentrations of 10−4 M the drug uptake amounts to 0.1 μmol per mg vesicular protein, 0.2 μmol drug per mg vesicular lipid and ∼0.4 μmol drug per mg phosphatidylcholine. 3. Drug binding is reversible and temperature independent. 4. Drug binding is not diminished when the phospholipids are hydrolysed by phospholipase A, C or D. 5. Drug binding is abolished by hydrogenation of the isolated lipids as well as of the lipids bound to the membranes. 6. In addition calcium uptake the Ca++ induced increase in ATP breakdown and the phosphate transfer reaction are inhibited when the lipids in the membranes are hydrogenated. 7. The normal ATPase as well as the lipid free proteins myokinase and actin are not affected by hydrogenation.
    Notes: Zusammenfassung 1. Reserpin, Chlorpromazin, Prenylamin und Imipramin werden sowohl von den isolierten Vesikeln des sarkoplasmatischen Reticulums (quergestreifte Muskulatur von Kaninchen) als auch von den aus diesen mit Chloro-form-Methanol (2:1) extrahierten Lipiden gebunden. 2. Bei einer Konzentration von 10−4 M werden Reserpin, Chlorpromazin und Prenylamin von dem intakten Lipoproteinkomplex der Vesikelmembran in Mengen von 0,1 μmol/mg Vesikelprotein, von 0,2 μmol/mg vesikulärem Total-Lipid und von ∼0,4 μmol/mg Phosphatidylcholin (Lecithin) gebunden. Lipidfreies Vesikelprotein hat keine Bindungsfähigkeit. 3. Die Bindung der Pharmaka ist reversibel und temperaturunabhängig. 4. Die Bindungsfähigkeit der Phospholipide ist nicht beeinträchtigt, wenn diese durch Phospholipase A, C oder D hydrolysiert werden. Sie wird jedoch aufgehoben durch Hydrierung der isolierten bzw. der membrangebundenen Lipide. Nach Hydrierung ist auch die Calcium-Aufnahme, die ATP-Extraspaltung und die Phosphatübertragung aufgehoben. 5. Die lipidfreien Proteine Myokinase und Actin werden durch den Hydrierungsvorgang funktionell nicht beeinflußt.
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  • 11
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 59-63 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 1,4-Dinitrobutan läßt sich mit Formaldehyd zum 2,5-Bis-(hydroxymethyl)-2,5-dinitro-hexan-1,6-diol (I) umsetzen. Durch katalytische Hydrierung konnte daraus das 2,5-Bis-(hydroxymethyl)-2,5-diamino-hexan-1,6-diol (II) gewonnen werden. Mit Formaldehyd und primären Aminen liefert I 1,2-Bis-[5′(5′-nitro-1′,3′-dialkyl-hexahydro-pyrimidyl)]-äthane (III) und 1,2-Bis-[5′(5′-nitro-3′-alkyl-tetrahydro-1′,3′-oxazinyl)]-äthane (IV).
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  • 12
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 243-251 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wurden verschiedenartig substituierte Acetylphenylester der Phosphor- und Thiophosphorsäure hergestellt und deren Wirksamkeit gegen Musca domestica geprüft. Es zeigte sich, daß eine lineare Abhängigkeit sowohl zwischen dem LD50-Wert und dem pK-Wert als auch zwischen dem LD50-Wert und der Verschiebung der Frequenz der OH-Valenzschwingung der zur Veresterung herangezogenen Phenole besteht, wenn diese in m- oder p-Stellung substituiert sind. Bei mehrfacher Substitution konnte diese Übereinstimmung nicht gefunden werden, da durch Wasserstoffbrückenbindung (o-Acetylphenol) oder sterische Hinderung, speziell bei angularen Erstsubstituenten (NO2- und COCH3Gruppe), die erwarteten Substitutionseinflüsse nicht voll wirksam werden.
    Additional Material: 2 Ill.
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  • 13
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 97-101 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wird über Darstellung und Eigenschaften von p-Nitrosocumol. p-Cumylborsäure, p-Cumylquecksilberacetat und einigen hiervon abgeleiteten Verbindungen berichtet, die als Modelle für substituierte Polystyrole dienen könen.
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  • 14
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es werden die Ergebnisse von Phasengleichgewichtsmessungen am genannten System bei einer Schnittemperatur von 45,0 °C mitgeteilt. Des weiteren wird versucht, die Konzentrationsabhängigkeit des Phasengleichgewichtes durch einen ternären MARGULES-Ansatz zu interpretieren und die von SCHUBERTH in (2) dargelegte Behauptung der besseren Darstellbarkeit mit B′=B′13 + B′23 gegenüber B′ = 0 zu überprüfen. Die hinreichend konsistenten Meßergebnisse scheinen eine Bestätigung der aufgestellten Behauptung zu erbringen.
    Additional Material: 5 Ill.
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  • 15
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 182-191 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Heterocyclische Hydrazine reagieren mit 2-Amino-1,3,4-oxdiazolen in Gegenwart von HCl unter Bildung von 1-Acyl-diaminoguanidinen, die in 5-Stellung heterocyclisch substituiert sind und bei der Oxydation 1-Acyl-C-amino-formazane liefern.In siedender Alkalilauge cyclisieren die Diaminoguanidine zu den Azobasen der in Nβ-Stellung heterocyclisch substituierten 5-Hydrazino-1,2,4-triazole.
    Additional Material: 3 Tab.
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  • 16
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968) 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 17
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 214-224 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wird über das Verhalten von Äthylaluminiumsesquichlorid, Triäthylaluminium und Diäthylaluminiumhydrid gegenüber Methylenchlorid, Chloroform und Tetrachlorkohlenstoff unter verschiedenen Reaktionsbedingungen berichtet.Methylenchlorid und Chloroform werden durch Äthylaluminiumsesquichlorid nicht angegriffen, durch Triäthylaluminium langsam enthalogeniert. Dagegen reagiert Tetrachlorkohlenstoff sehr heftig mit den ersten beiden Äthylaluminium-Verbindungen und führt zu Explosionen. Methylenchlorid eignet sich sehr gut als Lösungsmittel für aluminiumorganische Synthesen, wie bei der Darstellung von Ketonen aus Säurechloriden mit Hilfe von Äthylaluminiumsesquichlorid gezeigt wird.
    Additional Material: 6 Tab.
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  • 18
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 252-256 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Entgegen einer älteren Literaturangabe, wonach Einwirkung von Luftsauerstoff auf Isobutyraldehyd-diphenylaminal zu Hydrazobenzol führen soll, wurde festgestellt, daß unter C—C-Spaltung Diphenyl-formamidin entsteht. Die Reaktion läßt sich auf Aminale des p-Toluidins und des p-Chlor-anilins übertragen.
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  • 19
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 263-268 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Iron(III) forms in the aqueous medium a green complex with 8-hydroxy quinoline 7-sulfonic acid with maximum absorbence at 610 mμ, stable in the pH range 3-4. The composition of the complex as established by three different methods spectrophotometrically is Fe(III) EHQS (where EHQS is the abreviation used for 8-hydroxy quinoline 7-sulfonic acid). The stability constant calculated by the methods of BANERJI and DEY (1) and themole-ratio method (2) was found to be log K = 3.8 ± 0.05 at 25°C and the heat of formation was found to be = -5.24 k. cal/mole at 25°C.
    Additional Material: 6 Ill.
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  • 20
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 1-5 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: 1,4-Dioxan, Tetrahydrofuran and Dimethoxyäthan wurden unter Hochvakuum-Bedingungen über Kalium getrocknet und anschließend entgast. Die UV-Spektren und die elektrischen Leitfähigkeiten der hochgereinigten Äther wurden gemessen. Die Lösungsmittel konnten unter Hochvakuum-Bedingungen für einen beliebig langen Zeitraum ohne Veränderungen dieser physiko-chemischen Eigenschaften aufbewahrt werden. Behandlung mit Kalium unter Hochvakuum-Bedingungen führte zu einer teilweisen Spaltung der hochgereinigten Äther und hatte eine erhöhte elektrische Leitfähigkeit und Lichtabsorption zur Folge.
    Notes: 1,4-Dioxan, Tetrahydrofuran and Dimethoxyethan were dried over potassium and subsequently degassed, under high vacuum conditions. The u. v. spectra and the electric conductivities of the high purity ethers were measured. The solvents could be stored under high vacuum conditions for an unlimited period of time, without any changes of their physico-chemical properties. Treatment with potassium under high vacuum conditions caused a partial cleavage of the high purity ethers resulting in increased electric conductance and absorption of light.
    Additional Material: 4 Ill.
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  • 21
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 64-71 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wird die Synthese neuer Theophyllin- und Coffein-mercapto-essig- und -propionsäuren sowie einiger Ester derselben beschrieben.
    Additional Material: 2 Tab.
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  • 22
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 91-96 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Über die Bildung von p-Nitrosopolystyrol bei der Reaktion von Polystyrolquecksilberacetat mit Nitrosylchlorid wird berichtet, und es werden einige Umsetzungen an p-Nitrosopolystyrol beschrieben.
    Additional Material: 2 Ill.
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  • 23
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 113-121 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Durch kinetische Untersuchungen der Oxiranringöffnung mit Hilfe von Modellsubstanzen wird gefunden, daß die sterische Behinderung der Epoxidgruppe am Bicycloheptanring von Dicyclopentadien-dioxid bei der Reaktion mit Halogenwasserstoff in Dioxan nicht auf die Endomethylengruppe, sondern auf das während der Reaktion primär gebildete Halogenhydrin am Cyclopentanring zurückzuführen ist.Der starke Unterschied in der Reaktivität von HCl und HBr bei der Oxiranringöffnung von Dicyclopentadiendioxid in wasserfreiem bzw. wasserhaltigem Dioxan findet seine Erklärung in unterschiedlicher Protonenkonzentration des Reaktionsmediums. H0-Messungen mit verschiedenen Indikatoren liefern für HBr-Dioxan-Lösungen stets niedrigere H0-Werte als für entsprechende HCl-Dioxan-Lösungen.
    Additional Material: 12 Ill.
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  • 24
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968) 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 25
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 41-46 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wird die Protonierung der mit Thiotroponen iso-π-elektronischen Trithione (I), Isotrithione (II) und α-Dithiopyrone (III) sowie die Protonierung des Dithiobenzoesäure-methylesters (IV) und der cyclischen Trithiocarbonate (V) in wäßriger Schwefelsäure untersucht. Die H0-Werte der Halbprotonierung werden spektrophotometrisch abgeleitet und die Basizitäten mit den HMO-Elektronendichten verglichen.
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  • 26
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 72-77 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Die Umsetzungen von 1,8-Bis-brommethyl-naphthalin mit Dimethylsulfoxid, Na2S, NH3 und N-Bromsuccinimid werden beschrieben. Aus 1,8-Bis-dibrommethyl-naphthalin wurde über 1,3-Dimethoxy-1 H, 3H-naptho[1,8-cd]pyran und 1,3-Dihydroxy-1H,3H-naphtho[1,8-cd]pyran Naphthalin-1,8-dialdehyd dargestellt.
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  • 27
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968) 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 28
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 137-142 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wird über die Darstellung eines makromolekularen Polyradikals vom Diphenylstickstoffoxid-Typ berichtet. Die Struktur wird durch UV- und ESR-Spektren belegt.
    Additional Material: 5 Ill.
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  • 29
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 200-205 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wird über die Darstellung und Eigenschaften von Diselenoxanthogen-, Diselenokarbaminsäureestern, einigen Selenoharnstoffen und über die Reaktion von Diselenoxanthogenat mit Phosphoroxychlorid berichtet. Auf Versuche zur Darstellung von Bis(N,N-dialkylselenokarbamyl) diseleniden wird hingewiesen.
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  • 30
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 225-233 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The four geometric isomers of the 1,2,4-trimethylcyclohexanes, ctt, ctc, cct and ccc have been synthesized, characterized and their physical constants determined.In the course of the work the stereospecifity of a catalytic reduction method of some olefins and the WOLFF-KISHNER reduction of some ketones were demonstrated.
    Additional Material: 4 Ill.
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  • 31
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 234-242 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Für die Bestimmung von Zink in Pflanzensubstanzen eignen sich absorptionsflammen-photometrische und polarographische Methoden.Mit den zur Verfügung stehenden Gerätekombinationen konnten Messungen im Bereich von 1-5 μg Zn/ml bzw. 1-25 μg Zn/ml Meßlösung vorgenommen werden. Die Streubereiche betragen ±3,17 ppm bzw. ±3,25 ppm. Für die polarographische Bestimmung müssen störendes Phosphat und Sulfat durch Passage einer Kationenaustauschersäule abgetrennt werden. Die absorptionsflammenphotometrische Bestimmung wird durch die in Pflanzenproben vorliegenden Anionen und Kationen nicht gestört, sofern die Messung in 0,1 n HCl erfolgt. Für serienmäßige Arbeiten eignet sich das letztgenannte Verfahren besser, da mit dem polarographischen Verfahren bei gleicher Aufschlußprozedur nur die Hälfte an Bestimmungen geschafft wird. Dagegen ergibt sich bei diesem die Möglichkeit, in geringen Meßlösungsmengen von 0,5 ml zu messen. Die atomabsorptionsphotometrische Methode benötigt mindestens 3 ml Meßlösung.
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  • 32
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 257-262 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Monoalkylhydrazine werden erhalten, indem man in wäßriger Lösung Cyclohexanon nd ein Alkylamin mit Hydroxylamin-O-sulfonsäure zu einem 1-alkyl-3,3-pentamethylendiaziridin umsetzt und dieses nach Extraktion mit Toluol ohne Isolierung zu Monoalkylhydrazin und Cyclohexanon hydrolysiert. Durch Umsetzung von Monoalkylhydrazinen mit Kaliumcyanat zu 2-Alkyl-semicarbaziden und deren Fällung mit p-Nitrobenzaldehyd lassen sich gut kristallisierende Derivate herstellen. Durch Aminierung mit Hydroxylamin O—N-disulfonsäure werden Monoalkylhydrazine zu Stickstoff und zum entsprechenden Alkan abgebaut; letzteres wird gaschromatographisch identifiziert.
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  • 33
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 269-277 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Bei der Umsetzung von Aldonsäurehydraziden mit Bromcyan entstehen 2-Amino-5-polyhydroxyalkyl-1,3,4-oxidiazole, die sich mit Wasser in die entsprechenden Semicarbazide, mit Laugen in die entsprechenden 1,2,4-Triazolone-(5) umwandeln lassen. Die Polyhydroxy-1,3,4-oxidiazole lassen sich total acetylieren.
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  • 34
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 301-301 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 35
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 311-318 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es werden Versuche zur Darstellung 5′-substituierter Thymidine aus 5′-O-Arylsulfonylthymidinen beschrieben. Während die Knüpfung neuer C—O- oder von C—S-Bindungen nach Austritt der Arylsulfonyloxy-Gruppe am C-5′ prinzipiell möglich ist, wird bei Versuchen zur Knüpfung einer C—C-Bindung am C-5′ mit Kaliumcyanid O2,5′-Cyclo-thymidin erhalten. Mit Ammoniak reagieren die 5′-O-Arylsulfonyl-thymidine über O2,5′-Cyclothymidin zu 1-(2′-Desoxyribofuranosyl)-5-methyl-isocytosin und 5-Methylisocytosin.
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  • 36
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 9-19 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Der Hexamycinbildner 4/122 gehört zur Gattung Streptomyces. Für die Fermentation erwies sich ein Nährmedium mit Sojabohnenmehl am geeignetsten. Das Hexaenantibiotikum wurde aus dem Myzel mit Methanol und aus dem Kulturfiltrat mit n-Butanol extrahiert. Nach Abtrennen eines „ätherlöslichen Antibiotikums“ wurde das Rohprodukt mit Wasser extrahiert und durch Craig-Verteilung im System n-Propanol-Äther-Wasser (1:3:3) gereinigt. Lyophilisation aus tert.-Amylalkohol führte zu einer gelben, amorphen. Substanz.
    Additional Material: 7 Ill.
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  • 37
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 50-56 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wird die Synthese des vollständig geschützten Pentapeptids BOC-Orn(Z)-D-Leu-Ile-Orn(Z)-Orn(Z)-OMe beschrieben. Der Aufbau gelingt vorteilhaft durch stufenweise Synthese vom Carboxylende her unter Benutzung der Carbodiimid-, gemischten Anhydrid und Nitrophenylester-Methode.
    Additional Material: 1 Ill.
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  • 38
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 88-100 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Die WOLFF-Umlagerung der 1-Phthaloylamino-3-diazo-alkanone-(2) I a-d in Gegenwart von Anilin, DL-α-Phenyläthylamin, DL-β-Amino-β-phenyl-propionsäureäthylester and DL-Phenylalaninestern unter katalytischer Wirkung von Silberoxid oder durch Photolyse führt zu Derivaten des β-Alanins, der β-Amino-α-methyl-propionsäure, der β-Amino-α-äthyl-propionsäure und der β-Amino-β-phenyl-propionsäure. Die Verseifung der Estergruppierung der auf diesem Wege zugänglichen β-Phthaloylamino-propionyl-aminosäureester und anschließende Hydrazinolyse gibt die entweder aus zwei β-Aminosäuren oder einer β- und einer α-Aminosäure aufgebauten Dipeptide.
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  • 39
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 119-124 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The structure of (i) NaHg(CN)2(Cl)(H2O), (ii) NaHg(CN)2(Br)(H2O), (iii) NaHg(CN)2(CNS)(H2O), (iv) KHg(CN)2(Br) and (v) KHg(CN)2(CNS) has been studied by infrared spectroscopy. The structure of the anions of I, III and V complexes have been derived on the basis of characteristic absorption frequencies and other known properties and of II and IV on the basis of analogy as the CN groups in these complexes are infrared inactive. CN in these anions are linked as cyanide groups and SCN as isothiocyanate group in V. In III SCN is present both as thiocyanate and isothiocyanate group. III is monomeric with water as a coordinating group. In I and II water is not expected to be a ligand to Hg. Anions of I, II, IV and V are predominantly dimeric with CN as bridging group in the first three and SCN in V.
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  • 40
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 142-146 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wird über eine einfache und verallgemeinerungsfähige Synthese von Derivaten des Thiapyrons-(2) berichtet. Die Darstellung gelingt durch Umsetzung der β-Mercaptoverbindungen α, β-ungesättigter Carbonsäureester mit monosubstituierten Malonylchloriden.
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  • 41
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 177-181 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wird gezeigt, daß für N-Acyl-oxazolidine, -1,3-tetrahydrooxazine, -1,3-hexahydrooxazepine, 2-Alkyl-Δ2-thiazoline und 2-Alkyl-Δ2-thiazine Absorptionen im Bereich zwischen 900 und 1000 cm-1 charakteristisch sind. Diese Verbindungen wurden außerdem gaschromatographisch untersucht.
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  • 42
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 199-206 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wird über Untersuchungen des Verlaufs der Oxydation bei geradkettigen Monoolefinen am Modell Dodecen-1 berichtet, insbesondere über den stimulierenden Einfluß eines Zusatzes von Ozon zum Oxydationsgas auf den Reaktionsablauf.
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  • 43
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 246-252 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Interaction of the 1:1 Th-EDTA diaquo chelate with lactic, mandelic, o-hydroxy naphthoic acids has been investigated by the potentiometric technique. Formation of the mixed ligand chelate derivatives was indicated above pH 5.5. Equilibrium constants of the reactions have been determined.
    Additional Material: 3 Ill.
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  • 44
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 262-265 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A method for the analysis of microgram quantities of chloride and sulfate in nickel and nickel nitrate is given. The reliability of the method has been shown by a quantitative recovery of added chloride and sulfate from a solution of nickel nitrate. The method is being applied for the determination of these impurities in electrodeposited nickel. Methods are also given for the determination of boron and sulfide, found as impurities, in the electrodeposited nickel.
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  • 45
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 289-294 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Visible absorption spectra of Nickel (II) sulphate and various aliphatic amines were analysed, in order to extract information regarding each of amine Nickel (II) complex. The presence of six different complexes i.e., mono, di, tri, tetra, penta and hexamines have been indicated by the shift of absorption maxima for these. The energy changes of complexes due to exchange of water ligands with amines have been calculated and an interpretation is offered for this shift in the observed position of absorption maxima.
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  • 46
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 301-304 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A study of the physicochemical properties like refractive index, spectrophotometry, conductivity and pH measurements of a series of mixed solutions of uranyl nitrate and mercurous nitrate have shown the existence of two complexes in solution in the (1:1) and (1:2) molecular ratios respectively viz. \documentclass{article}\pagestyle{empty}\begin{document}$$ \begin{array}{*{20}c} {{\rm UO}_2 \left({{\rm NO}_3 } \right)_2 \cdot {\rm Hg}_2 \left({{\rm NO}_3 } \right)_2,} \hfill & {\left({\rm i} \right)} \hfill \\ {{\rm UO}_2 \left({{\rm NO}_3 } \right)_2 \cdot 2{\rm Hg}_2 \left({{\rm NO}_3 } \right)_2,} \hfill & {\left({{\rm ii}} \right)} \hfill \end{array} $$\end{document}Both the above mentioned compounds have been detected only in the solution by the breaks in the usual curves when various properties like conductivity, refractive index, spectrophotometry and pH were plotted against the m.l. of mercuric nitrate (M/10) added to a fixed volume of uranyl nitrate (M/10).
    Additional Material: 3 Ill.
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  • 47
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 358-361 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A rapid amperometric method for the determination of vanadium (V) has been described which involves titration of vanadium (V) as sodium orthovanadate against copper sulphate solution at Ede = - 0.20 V (vs S.C.E.). The accuracy and reproducability of the method is excellent particularly at higher temperature i.e. at 60°C. The method permits the determination of vanadium (V) down to 0.2 mM with an accuracy 1.0%).
    Additional Material: 1 Ill.
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  • 48
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 366-368 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Three hexaco-ordinated complexes of nickel (II) acetate with ammonia, ethylenediamine and propylenediamine have been prepared. Conductivity measurements indicate the complexes to be non-electrolytes. Molecular weight measurements confirm this. The visible absorption spectrophotometric measurements show a number of bands corresponding to the various permitted transitions of the metal and a discussion of the structure in the light of these transitions is presented.
    Additional Material: 1 Tab.
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  • 49
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 375-377 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Some complexes of cerium (IV) sulphate with ammonia and primary aliphatic amines have been prepared. The molecular formulae on the basis of analysis turn out to be Ce(SO4)2 · 4 amine. The complexes behave as electrolytes. The absorption spectra have been recorded and an interpretation is offered for possible transitions.Lanthanides, and cerium in particular are receiving special attention these days. A number of complexes of latter with various ligands and anions have been reported1-5). In the present paper some complexes of cerium (IV) sulphate with ammonia, methyl, ethyl, propyl and butylamine are being presented.
    Additional Material: 1 Tab.
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  • 50
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 369-374 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Some substituted sulphonamides have been cyanoethylated and they were subjected to reduction. On hydrolysis with aqueous and alcoholic sodium hydroxide the cyanoethylated sulphonamides gave decyanoethylated products identical to the original sulphonamides.
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  • 51
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 378-381 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Some molecular addition compounds of cobalt (II) oxalate with primary aliphatic amines have been prepared. The general molecular formula on the basis of analysis of constituent elements turn out to be CoC2O4 · RNH2. The formation of compounds is independent of the excess amine concentration. The compounds behave as electrolytes. The molecular weight measurements and VAN'T HOFF factor “i” also confirm this fact.
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  • 52
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 386-390 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis of 3-methyl-6,7-benzo-5′(4′)-methyl furano-(2′,3′,1,2) xanthones has been recorded.
    Additional Material: 4 Ill.
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  • 53
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 382-385 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The co-ordination compounds of tripositive iron with nitrogen containing ligands have been found to be of high spin type on the basis of magnetism. The ultraviolet and visible absorption measurements show three bands in the vicinity of 21 400 cm-1, 17 480 cm-1 and 10 650 cm-1.
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  • 54
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 391-396 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 5- und 6-gliedrige 2-Alkyl-cycloalkandione-(1, 3) erhält man durch Umsetzung von Dicarbonsäurehalogeniden mit Carbonsäuren oder von Carbonsäurehalogeniden mit Dicarbonsäuren unter FRIEDEL-CRAFTS-Bedingungen.
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  • 55
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 34-39 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wird über Darstellung, Analyse und einige Eigenschaften der 2-Methylmercapto-4-methylphenylarsonsäure berichtet. Folgende Reaktionswege führten zum Ziel: (a) 4-Methylanilin → 2-Nitro-4-methylanilin → 2-Nitro-4-methylphenylarsonsäure → 2-Amino-4-methylphenylarsonsäure → 2-Methylmercapto-4-methylphenylarsonsäure; (b) 4-Methylanilin → 2-Amino-6-methylbenzthiazol → 2-Mercapto-4-methylanilin (alkalische Lösung) → 2-Methylmercapto-4-methylanilin → 2-Methylmercapto-4-methylphenylarsonsäure.
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  • 56
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 162-167 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Die Umsetzung der Acetonketale des Glycerins und des Trimethylolpropans mit Adipinsäureanhydrid liefert Adipinmono- und -diester. Durch nachfolgende Abspaltung der Acetonschutzgruppierungen gelangt man zu Mono-[2, 3-dihydroxypropyl]-adipat, Bis-[2, 3-dihydroxypropyl]-adipat, Mono-[2, 2-dihydroxymethyl-butyl]-adipat, Bis-[2, 2-dihydroxymethyl-butyl]-adipat.
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  • 57
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 20-33 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Das UV-Spektrum des Hexamycins besitzt Maxima bei 336, 356 und 376 nm. Im IR-Spektrum ist die typische Bande der Makrolid-Polyenantibiotika bei 1712 cm-1 enthalten. Der Schmelzpunkt beträgt 120-125°C, das Äquivalentgewicht 824, die Molmasse liegt zwischen 700 und 800. Hexamycin ist in polaren organischen Lösungsmitteln löslich und unlöslich in Wasser und nicht polaren Lösungsmitteln. Lösungen der Substanz verlieren ihre antibiotische Aktivität sowohl durch Erhitzen als auch bei längerem Stehen. Von 21 geprüften Mikroorganismen, vorwiegend Pilze, werden weit über die Hälfte durch 2-32 μg/ml gehemmt. Der Einfluß des Hexamycins auf die Polyphenoloxydase- und Peroxydaseaktivität ist gering. Die Atmung von Saccharomyces cerevisiae Hansen wird durch Hexamycin beträchtlich gemindert.
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  • 58
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 57-68 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Die Ergebnisse von Gleichgewichts- und kinetischen Messungen der syn-parallelen Cyclisierung diastereomerer 1,2-Aminoalkohole mit Ketonen werden diskutiert. Es wird gezeigt, daß in der Mehrzahl der untersuchten Fälle sterische Faktoren die Gleichgewichtslage und die Reaktionsgeschwindigkeit entscheidend beeinflussen.
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  • 59
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 101-106 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Monothio-dibenzoylmethan ist wesentlich reaktionsfähiger als Dibenzoylmethan. Die üblichen Carbonylreagenzien greifen stets zuerst die Thiocarbonylgruppe an. Die Monokondensationsprodukte sind daher schwefelfrei. Wenn sich Bis-kondensationsprodukte bilden, wird zuerst H2S und dann H2O abgespalten. Die Umlagerung der Enol-Form des Monothio-dibenzoylmethans in die Enthiol-Form erfolgt wahrscheinlich direkt und nicht über die Oxo-thioxo-Form.
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  • 60
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 130-136 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: High frequency ultrasonic waves of frequency 1 Mc/s. have been employed to study the decolourization of dilute aqueous solution of crystal violet. The process is irreversible and the kinetic study shows it to be unimolecular one. The deaeration of the solution by nitrogen does not affect the rate of the decolourization. The addition of certain substances such as alcohol, acetone, ether, glycerine, dioxan and allylthiourea inhibits the decolourization to a considerable extent. Oxidation and subsequent destruction of the dye molecule has been found to be the cause of the fading of the dye solution.
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  • 61
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 147-149 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Ätherische Titantetramethyllösungen lassen sich einfach durch Einwirkung von Titan(IV)-chlorid auf Methylmagnesiumhalogenidlösungen darstellen. Geeignete Apparaturen werden im folgenden beschrieben.
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  • 62
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 168-176 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 2α, 3α- und 2β, 3β- Benzoylimino-cholestan werden durch Natriumjodid in siedendem Aceton zu 2′-Phenyl-(2α, 3α)-oxazolino-[5′, 4′:2, 3]-cholestan bzw. 2′-Phenyl-(2β, 3β)-oxazolino-[5′, 4′:3, 2]-cholestan umgelagert. Mit Bortrifluoridätherat in absolutem Äther bildet 2α, 3α-Benzoylimino-cholestan ebenfalls 2′-Phenyl-(2α, 3α)-oxazolino-[5′, 4′:2, 3]-cholestan. Dagegen erfolgt durch verdünnte Schwefelsäure oder Pikrinsäure in Aceton sowie durch Benzoesäureanhydrid oder Pikrinsäure in Alkohol Ringöffnung zu 2-Hydroxybzw. Alkoxybenzamiden. Die Ringschlußreaktion des diaxialen 2β-Chlor-3α-benzaminocholestan führt mit Natriumhydrogenkarbonat zum Oxazolin, während mit Kaliumhydroxid 2α, 3α-Imino-cholestan entsteht.
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  • 63
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 207-221 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wird über Untersuchungen zur Epoxidbildung bei der Oxydation geradkettiger Olefine berichtet. Diese kann durch Zusatz von Ozonid oder Carbonyl auf über 50% des umgesetzten Olefins erhöht werden.
    Additional Material: 19 Ill.
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  • 64
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 192-199 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Carboxyl- bzw. Aldehyd-geschützte Glyoxylsäurederivate wurden für Isonitril-Reaktionen nach UGI eingestzt: Glyoxylsäureamide gaben je nach Reaktionskomponenten Diamide der Aminomalonsäure oder Derivate des Tetrazolyglycins. - Acetale von Glyoxyloylaminosäureamiden (9a, b) wurden aus Dialkoxyessigsäure gewonnen. Das analog aus Dichloressigsäure zugängliche Dichloracetylderivat 9c gab mit Amin ein Aminal, das sich ebenso wie 9a sauer zum entsprechenden 2-Hydroxypiperazin-dion-(3,6) 11a hydrolysieren ließ. - Lävulinsäure konnte mit Amin/Isonitril zu Pyrrolidon-5-carbonsäureamiden cyclisiert Werden.
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  • 65
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 302-310 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Die Aminomethylierun von aliphatischen α-Keto-dicarbonsäurediäthylestern und Dicarbonsäurediäthylestern mit mittelständiger Ketofunktion ergab Dimethylaminomethyl-keto-dicarbonsäurediäthylester, deren Hydrochloride thermolytisch in die entsprechenden Methylen-keto-dicarbonsäurediäthylester übergeführt wurden.
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  • 66
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 1-8 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A detailed analytical scheme for the determination of different sulphur compound types in Bakr crude oil distillate fractions up to 350°C was carried out. The quantitative distribution of elemental sulphur, hydrogen sulphide, mercaptans, aliphatic sulphides, aromatic sulphides, reducible and thiophenic sulphur compound types was studied.
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  • 67
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 40-49 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Die Synthese von Sultamen des p-Xylidins, des 2-Amino-1,3-dimethylbenzols, des 2-Aminoanthrachinons, der p-Aminosalicylsäure und der m-Aminosalicylsäure und einiger ihrer Derivate wird beschrieben. Aus den Butadien-(1,3)-sultamen von zwei Xylidinen konnten die entsprechenden N-Dimethylphenyl-pyrrole hergestellt werden.
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  • 68
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 77-87 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Die Reaktion von primären langkettigen Alkylhalogeniden mit Alkalicyanat in Dimethylformamid verläuft in Gegenwart stöchiometrischer Wassermengen schnell und vollständig zu den entsprechenden N,N′-Dialkylharnstoffen. Langkettige α,ω-Dihalogenalkane setzen sich analog zu den entsprechenden Polyharnstoffen um. Sekundäre Alkylhalogenide lassen sich mit schlechteren Ausbeuten in verzweigte N,N′-Dialkylharnstoffe überführen. Die als Zwischenprodukte zu erwartenden Alkylisocyanate konnten isoliert werden.
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  • 69
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 113-118 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wird eine neue Gruppe thiophosphororganischer Verbindungen O,O-Dialkyl-S-(aryldisulfido)-dithiophosphate und deren IR-Spektren berichtet.
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  • 70
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    Helvetica Chimica Acta 51 (1968), S. 153-163 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The occurrence of so-called synchronous 7-centre-fragmentation has been excluded for γ-amino-ketoxime derivatives N—C—C—C—C=N—X. Fragmentation may occur, however, by another route.Reaction rates of the p-toluenesulfonates of (4-quinuclidinyl)-methyl-ketoxime (10b) and (3β-tropanyl)-methyl-ketoxime (14b) in 80% ethanol and the resulting products have been determined. Whereas the latter γ-aminoketoxime underwent quantitative BECKMANN rearrangement to 3β-acetylaminotropane (29), the former yielded 3% fragmentation products besides rearranged 4-acetylamino-quinuclidine (13).A kinetic study reveals that both 10b and 14b react via the rearranged nitrilium ions 12a and 16a, respectively. In the case of the N-(4-quinuclidinyl)-acetonitrilium ion (12a) 5-centre-fragmentation competes with hydration to the amide 13.
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  • 71
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: (1) A method is described which allows the elucidation of the structure of cotton cross-linked with formaldehyde. It consists of a permethylation process (5 methylations with dimethyl sulphate and sodium hydroxide in dimethyl sulphoxide, followed by two exchange methylations of the formalised sodium cellulosate with methyl iodide in n-butanol), hydrolysis of the product in 72% sulphuric acid to the respective methylated glucoses, reduction of the mixture of glucoses to the respective sorbitols, blocking of all free hydroxyl groups by acetylation, trifluoroacetylation or formation of trimethylsilyl ethers, and vapour phase chromatographic separation of the derivatives.(2) It is shown that after permethylation practically no free hydroxyl groups can be detected and that scarcely any replacement of methylene or oxymethylene cross-links by methyl groups has taken place. With the exception of losses in filtration of the permethylation product, all stages of the process proceed on an almost quantitative basis.
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  • 72
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction between phenol and trans penta-2,4-dienyl chloride gave trans penta-2,4-dienyl Phenyl ether (I), whereas with a mixture of sorbyl chloride and 1-methylpenta-2,4-dienyl chloride, pure trans, trans hexa-2,4-dienyl phenyl ether (IV) and trans 1-methylpenta-2,4-dienyl phenyl ether (V) were obtained. The ether I gave, on heating in dilute solution at 185°, 4-(penta-2,4-dienyl)-phenol (III) as the main product, and also some 2-(2-vinylallyl)-phenol (II). The ether IV provided, on heating at 165°, in addition to the ortho CLAISEN rearrangement product VI, mainly a mixture consisting of 94% 4-(1-methylpenta-2,4-dienyl)-phenol (VIII) and only 6% 4-(hexa-2,4-dineyl)-phenol(IX). The latter product (IX) was the only para isomer produced on heating ether V, but in addition 22% of the ortho rearrangement product VII was formed.The migrations I → III, IV → VIII, and V → IX, proceeding through a ten membered transition state, are the first [5,5] sigmatropic rearrangements described.
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  • 73
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    Helvetica Chimica Acta 51 (1968), S. 206-210 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A total synthesis of hystrine has been realised with good yield by the introduction of a double link into the piperidine nucleus of synthetic ammodendrine, followed by deacetylation, and purification with the aid of the nitroso derivative.The identity of the synthetic product with authentic hystrine was established by its chromatographic behaviour, by UV.-, IR.- and mass spectra as well as by the properties of its nitroso derivative. Thus the proposed structure of hystrine as 3-(2, 3, 4, 5-tetrahydropyrid-6-yl)-1, 4, 5, 6-tetrahydropyridine (V) is proved.
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  • 74
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The phase diagram of the technical important fusion system pyridine-aluminiumchloride was determined by classical thermo-analysis, proving the existance of a hitherto unknown pyridine-aluminium chloride 2:1 complex.
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  • 75
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    Helvetica Chimica Acta 51 (1968), S. 311-325 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Pachybiose (1) is shown to be 4-O-(3-O-methyl-6-deoxy-β-D-allopyranosyl)-D-oleandrose and asclepobiose (14) 4-O-(3-O-methyl-6-deoxy-β-D-allopyranosyl)-D-cymarose.
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  • 76
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Condensation of the tetrahydropyranyl ether of the α-hydroxyalkyl-thioamides with 3-bromo-4-hydroxy-2-pentanones yields DL-2-(α-hydroxyalkyl)-4-methyl-5-(β-hydroxyethyl)-thiazoles. By oxidation with chromic anhydride 2-hydroxymethyl-4-methyl-5-(β-acetoxyethyl)-thiazole yields the corresponding 2-formyl derivative. The latter compound reacted with GRIGNARD complexes gives the homologous DL-2-(α-hydroxyalkyl)-4-methyl-5-(β-hydroxyethyl)-thiazoles. This is a general method for the synthesis of the thiazole part of the «active aldehydes».2-Acetyl-4-methyl-5-(β-hydroxyethyl)-thiazole is also obtained by chromic oxidation of the suitable methylthiazol-2-yl-carbinol.The condensation of the thioamides obtained from the α-ethoxycarbonyl-nitriles with 3-bromo-5-acetoxy-2-pentanone results in the DL-2-(α-ethoxycarbonyl-alkyl)-4-methyl-5-(β-acetoxyethyl)-thiazoles. The α-hydroxyl function is introduced into the 2-(α-ethoxycarbonyl-alkyl) group by chlorination with sulfuryl chloride and replacement of the introduced chlorine by acetate. The latter compounds are the esters of the thiazole part of the «active α-oxo-carboxylic acids» (e.g. active pyruvate, etc.).The reaction of 2-(α-hydroxyalkyl)-4-methyl-5-(β-hydroxyethyl)-thiazoles and 2-(α-ethoxycarbonyl-α-acetoxy-alkyl)-4-methyl-5-(β-acetoxyethyl)-thiazoles, respectively, with alkyl, alkenyl and aralkyl haloids, or with 2-methyl-4-amino-5-bromomethyl-pyrimidine hydrobromide results in the quaternary thiazolium compounds belonging to the group of the active aldehydes, active α-oxo-carboxylic acids, etc. According to this method 2-hydroxymethyl-thiamine bromide hydro-bromide has been synthesized, which can be considered as the pyrophosphate-free «active formal-dehyde».The 2-α-hydrogen atom in 2-(α-hydroxyalkyl)-thiazolium compounds cannot be replaced by deuterium under conditions similar to those used for the H → D exchange in thiamine.The main peaks in the mass spectra of 2-(α-hydroxyalkyl) substituted thiazoles and thiazolium quaternary salts are listed.
    Additional Material: 2 Tab.
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  • 77
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    Helvetica Chimica Acta 51 (1968), S. 1-16 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The authors propose for the characterization of strepogenic substances of known composition the specific activity, i. e. the number of WOOLLEY units per μmole.Starting from L-leucyl-L-cystinyl-L-leucyl-L-valyl-L-glutamic acid (of very high strepogenine activity, 400 WOOLLEY units per mg, 230 WOOLLEY units per μmole) seven peptides have been synthesized by suppression and/or replacement of amino acid residues. A study of the relation between activity and structure of these peptides shows that: In this group cystine is an indispensable element for activity.This amino acid must either be linked on each side to leucine residues or linked by its carboxyles to leucine, its amino groups being free.From these results, the conception emerges that the strepogenine polypeptides may be characterized by an amino acid (in this group of peptides, cystine) which must be linked to particular amino acid residues. If this conception is correct, there should exist several types of strepogenines depending on the nature of the amino acid essential for their activity.
    Additional Material: 1 Ill.
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  • 78
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    Helvetica Chimica Acta 51 (1968), S. 67-74 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Disazo dyes from 6-amino-1-hydroxy-naphthalene-3-sulfonic acid (J acid) were synthesized by coupling ortho-hydroxy monoazo dyes with different diazonium compounds in acid medium (dyes No 3-14. A second coupling to the ortho position of the amino group was also possible with the copper complexes of o,o' -dihydroxy monoazo dyes from 8-amino-1-hydroxynaphthalene-3,6-disulfonic acid (H acid) dyes No 19-22). This is a reversal of the well known rule that the formation of disazo dyes with aminonaphthol-sulfonic acids is only practicable when an acid coupling is followed by an alkaline one. 5-Amino-1-hydroxy-naphthalene-3-sulfonic acid (M acid), which is said to form no disazo dyes, could be coupled twice with several diazonium compounds to yield disazo dyes (dyes No 24, 26, 27, 29).
    Additional Material: 2 Tab.
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  • 79
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    Helvetica Chimica Acta 51 (1968), S. 94-105 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of the reaction of murexide with different divalent metal ions of class A and B have been measured by the temperature-jump-relaxation method. The second-order formation rate constant increases in the sequence Ni2+ 〈 Co2+ 〈 Mn2+ 〈 Zn2+ 〈 Cd2+ ˜ Cu2+ ˜ Ca2+ 〈 Sr2+ 〈 Ba2+ 〈 Pb2+.Thermodynamic data obtained from kinetic and equilibrium studies, respectively, are in good agreement. The results are compared with the characteristic rate constants for H2O-exchange in the inner coordination sphere of these metal ions, which follow the same sequence. The rate constants of the reaction of murexide with various trivalent metal ions, including the lanthanides, are also discussed in terms of current ideas on metal complex formation.
    Additional Material: 1 Ill.
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  • 80
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The total or partial structure determinations of some new components from Dregea abyssinica are reported. The four drebyssogenins (F, G, J and H) are esters of the drevogenins P (7) and D(9) and have the following structures: Drebyssogenin F (5) = 11-O-acetyl-12-O-(α-hydroxyisovaleryl)-drevogenin P, drebyssogenin G (14) = 11-O-acetyl-12-O-isovaleryl-drevogenin D, drebyssogenin J (15) = 11, 12-di-O-acetyl-drevogenin D. Drebyssogenin K is a mixture of K1 (16) and K2 (17), the mono-O-tiglyl and mono-O-isovaleryl derivatives of drevogenin D respectively, with as yet undetermined position of the acyl residues. The drebyssosides 1, 2 and 3 are glycosides of trisaccharides. Drebyssoside 1 (2) is pachybiosyl-cymarosyl-drevogenin A, drebyssoside 2 (3) asclepobiosyl-cymarosyl-drevogenin A and drebyssoside 3 (6) pachybiosyl-cymarosyl-drebyssogenin F. Drebyssoside 4 is a mixture of at least two components and contains the same aglycones and the same sugar units as the drebyssosides 1 and 3, but is different from them. The full structure of the two sugars (drebyssobiose (25) and sugar T (24)) has not been determined; it is only shown that both are disaccharides which contain 3-O-methyl-6-deoxy-allose linked to a 2-deoxyhexose.
    Additional Material: 10 Ill.
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  • 81
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    Helvetica Chimica Acta 51 (1968), S. 526-529 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A new organo-metallic titanium-zinc compound [Ti(C5H5)2Cl]2ZnCl2 has been isolated. Its structure has been characterised by means of spectroscopic, susceptibility and dipole measurements.
    Additional Material: 2 Tab.
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  • 82
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    Helvetica Chimica Acta 51 (1968), S. 529-532 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The proton spectrum of furan oriented in the nematic phase of anisoleazophenyl-n-capronate has been analysed. The ratios of the various interproton distances as well as the orientation parameters and the signs of the indirect coupling constants for furan are determined.
    Additional Material: 1 Ill.
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  • 83
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    Helvetica Chimica Acta 51 (1968), S. 569-576 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In earlier publications [1] [2] [3] [4] a pyranoid structure has been proposed for the sugar moiety of imidazoline and imidazolidine derivatives from D-glucosamine. But by NMR.-spectra and periodate oxidation the sugar moiety of these compounds and of similar derivatives from other 2-amino-2-deoxy-sugars is now shown to be of furanoid structure.
    Additional Material: 2 Ill.
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  • 84
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    Helvetica Chimica Acta 51 (1968), S. 598-598 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 85
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    Helvetica Chimica Acta 51 (1968) 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 86
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    Helvetica Chimica Acta 51 (1968), S. 1037-1051 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The present day quantum chemistry is mathematically based on von NEUMANN'S formulation of quantum mechanics and therefore not able to deal correctly with anomal quantum states. A general theory of large molecules and large molecular systems has to be founded on quantum field theory allowing for inequivalent irreducible representations. It is proposed to formulate quantum chemistry in the framework of the B*-algebra of the observables. The paradox of molecular systems having an infinite number of degrees of freedom is discussed, and the possible significance of anomal molecular quantum states for molecular biology is pointed out.
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  • 87
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Treatment of 2β-tosyloxy-A-nor-5α-cholestane-5-ol (2) with t-butoxide in t-butanol gave 2α, 5-epoxy-A-nor-5α-cholestane (3) in quantitative yield.When A-nor-5β-cholestane-2α, 5-diol (4) was treated with tosyl chloride in pyridine 2β-chloro-A-nor-5β-cholestane-5-ol (7) and 2α-tosyloxy-A-nor-5β-cholestane-5-ol (8) were obtained. Whereas the chloride 7 was resistant to t-butoxide the tosylate 8 was transformed into an 1 : 1 mixture of 2α, 5-epoxy-5β-cholestane (10) and 2ξ-t-butoxy-A-nor-5β-cholestane-5-ol (11). In 2α-tosyloxy-A-nor-5α-cholestane-5-ol (12) substitution occurred as the only reaction.Both oxetanes 3 and 10 isomerize after heating above 50° and in polar or protic solvents to form A-nor-Δ3(5)-cholestene-2α-ol (6) and -2β-ol (14) respectively. Also, 2, 5-diols are encountered.2α-Ethyl-2β, 2′-epoxy-A-nor-5α-cholestane (23) was synthesized starting from A-nor-5α-cholestane-2-one (17). The intermediates were the ester 16, the diol 18, the hydroxy-tosylate 19 and the chlorhydrin 20. The spirocyclic oxetane 23 was reduced by LiAlH4 in dioxane (not in ether). By chromatography on silica gel 23 was isomerized to the homoallylic alcohol 21 and transformed into 2-methylene-A-nor-5α-cholestane (24) by fragmentation.The IR. and NMR. spectra of the new oxetanes were compared with those of a series of known oxetanes.
    Additional Material: 3 Ill.
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  • 88
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    Helvetica Chimica Acta 51 (1968), S. 1095-1102 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: On décrit la préparation, à partir de la dibromo-2, 5-téréphtalophénone et de quelques-uns de ses dérivés méthylés, par déshydrobromation accompagnée d'une double cyclisation, de la trans-fluorénacène-dione (dioxo-6, 12-dihydro-6, 12-indéno [1, 2-b] fluorène) et de quelques dérivés méthylés. Ces dicétones polycycliques sont colorées en orangé, rouge ou violet, et cuvables. Leur réduction selon WOLFF-KISHNER fournit les hydrocarbures correspondants.
    Additional Material: 1 Tab.
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  • 89
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    Helvetica Chimica Acta 51 (1968), S. 1051-1060 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Magneto-optical rotatory dispersion (MORD.) of saturated aliphatic hydrocarbons can be described very accurately by an equation of the DRUDE type. The two parameters, appearing in such an equation, have been determined from MOR. measurements in the region of 240 to 500 nm by the method of least squares. These parameters show a systematic dependence on the structure of the investigated hydrocarbons. An empirical rule for the approximation of the DRUDE parameters is given which in turn allow the calculation of the VERDET constant for a given structure at any wavelength between 240 and 500 nm.
    Additional Material: 1 Ill.
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  • 90
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    Helvetica Chimica Acta 51 (1968), S. 1108-1119 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 7-Aminocephalosporanic acid or esters thereof are prepared either by intramolecular aminolysis of esters of the antibiotic cephalosporin C or vïa imino-ethers derived from the latter.A simple procedure for the preparation of 7-aminocephalosporanic acid in high yield is described.
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  • 91
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    Helvetica Chimica Acta 51 (1968), S. 1155-1158 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A total synthesis of hog thyrocalcitonin is described. A protected C-terminal tridecapeptide amid (20-32) was coupled with a protected central decapeptide (10-19), and the resulting protected tricosapeptide amide (10-32) was reacted with the N-terminal protected nonapeptide (1-9). After elimination of the protective groups, a free dotriacontapeptide amide was obtained whose physical, chemical and biological behaviour was indistinguishable from that of the natural hormone.
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  • 92
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    Helvetica Chimica Acta 51 (1968), S. 1184-1184 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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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 synthesis of 2-picolylidene-bis-(p-phenylsulfuric acid) disodium salt (I, DCI: ‘sodium picosulfate’) has been realized by two routes. I has been characterized by the usual analytical data and UV., IR. and PMR. spectral properties.
    Additional Material: 2 Ill.
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  • 94
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    Helvetica Chimica Acta 51 (1968), S. 1203-1213 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reactivity of hydroxy-indoles under the conditions of the Mannich-reaction has been studied. The electrophilic side-chain enters in each case in a position ortho to the phenolic group. 4-Hydroxy-indole is substituted in the 5-, 5-hydroxy-indole in the 4-, 6-hydroxy-indole in the 7-, and 7-hydroxy-indole probably in the 6-position. The structures of the Mannich bases from 4-, 5- and 6-hydroxy-indole have been confirmed by comparison of the hydroxy-methyl-indoles obtained by reductive desamination with hydroxy-methyl-indoles prepared by unambiguous total synthesis.
    Additional Material: 3 Tab.
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  • 95
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    Helvetica Chimica Acta 51 (1968), S. 1409-1420 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 1, 2-Dithioles with sulfur substitutents in position 5 are prepared by reaction of 4-chloro-1, 2-dithiol-3-ones with thiols, sulfinates, dithiocarbamates, or potassium ethylxanthate. Bis-(4-chloro-1, 2-dithiol-3-on-5-yl) sulfide is produced from 4, 5-dichloro-1, 2-dithiol-3-one with sodium thiosulfate and other thiol forming reagents. The 5-alkylthio- and 5-arylthio-1, 2-dithiol-3-ones can be oxidized with peracids to sulfoxides and, partly, to sulfones; the sulfones can also be obtained from sulfinates. 4-Chloro-5-(α-methyl-benzylthio)-1, 2-dithiol-3-one reacts differently with peracetic acid, giving bis-(4-chloro-1, 2-dithiol-3-on-5-yl) disulfide besides 4-chloro-1, 2-dithiol-3-one. With oxalyl chloride, 4-chloro-5-alkylthio-1, 2-dithiol-3-ones form 3, 4-dichloro-dithioliumchlorides, which react with anilines to give 3-phenylimino-4-chloro-5-alkylthio-1, 2-dithioles.
    Additional Material: 6 Tab.
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  • 96
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Senecio alpinus (L.) SCOP. is very rich in alkaloids. The dried overground parts gave 0,45% crude alkaloid mixture. The main component is seneciphylline (1); small amounts of cristalline jacozine (4) could also be isolated. - Senecio subalpinus KOCH gave 0,368% of crude alkaloid mixture. In contrast to former results only 0,1% of this was present in the form of N-oxides. The bulk was a ca. 1 : 1 mixture of seneciphylline with senecionine (3). - Senecio incanus L. subsp. carniolicus (WILLD) BRä.-BL. gave 0,40% of crude alkaloid mixture; from this some pure seneciphylline could be isolated. - In all three plants the presence of integerrimine (2) and other non-identified alkaloids could be established by thin layer chromatography.
    Additional Material: 2 Ill.
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  • 97
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    Helvetica Chimica Acta 51 (1968), S. 1130-1133 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A method for the preparation of pure crystalline aldolase (type A) from pupae of Drosophila melanogaster is described.
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  • 98
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    Helvetica Chimica Acta 51 (1968) 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 99
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    Helvetica Chimica Acta 51 (1968), S. 1537-1548 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In the bromodesulfonation of sodium 2, 6-dibromophenol-4-sulfonate (I) and similar compounds, the relatively stable quinoloid intermediate II exchanges its carbonyl oxygen with that of H218O by an addition-elimination process. The exchange is slower than the formation of the product III; it is roughly comparable to the exchange velocity of quinones of similar structure. By reversibility of the electrophilic additon step, 18O is incorporated into the starting phenol I. In electrophilic substitutions with shorter life-time of the quinoloid intermediate, the oxygen exchange is difficult or impossible to observe.
    Additional Material: 1 Ill.
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  • 100
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    Helvetica Chimica Acta 51 (1968), S. 1381-1383 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: On every line of a X-ray powder-diagram there is more than one reflection, at least there are hkl and hkl. In the tetragonal, trigonal-hexagonal and cubic crystalsystems, these systematically coinciding reflections generally have different intensities (2 or 4 kinds), except in the highest-symmetry LAUE class.So in structure determination, the conventional reliability quotient R has to be replaced by \documentclass{article}\pagestyle{empty}\begin{document}$$ \tilde R = (\Sigma |\tilde F_{obs}^2 - \tilde F_{cal}^2 |)/\Sigma \tilde F_{obs}^2, $$\end{document} where the \documentclass{article}\pagestyle{empty}\begin{document}$ \tilde F^{2,}s $\end{document}2's are the sums of the 2 or 4 (LP-corrected) intensities coinciding on a line. An IBM-1620 program was written to calculate \documentclass{article}\pagestyle{empty}\begin{document}$ {\tilde R} $\end{document}, starting with the output of ICR-4 structure factor program. An application is given in the immediately following paper by LUDI,GÜDEL and BÜRKI.
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