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  • 1
    Electronic Resource
    Electronic Resource
    Primary thymic carcinoid with Cushing's syndrome (1992)
    Springer
    Virchows Archiv 420 (1992), S. 191-195 
    Details
    ISSN: 1432-2307
    Keywords: Thymic carcinoid ; Cushing's syndrome ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In a 52-year-old Caucasian man osteopoikilosis had been misdiagnosed roentgenologically 2 years before his death. Gradually he developed Cushing's syndrome and ultimately superior vena caval obstruction. At autopsy a primary thymic carcinoid with extensive osteoblastic bone metastasis was found. Immunohistochemically the tumor was shown to be positive for adrenocorticotropic hormone (ACTH), cytokeratin (KL1), neuron-specific enolase, synaptophysin, chromogranin and glucagon. Remarkably the tumour was negative for serotonin despite high urinary hydroxyindolacetic acid levels. Bilateral hyperplasia of the adrenal cortex was found. The adenohypophysis showed a considerable reduction of ACTH-producing cells and numerous Crooke's cells with a characteristic immunohistochemical pattern.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02358812
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  • 2
    Electronic Resource
    Electronic Resource
    Metabolic changes in patients with mitochondrial myopathies and effects of coenzyme Q10 therapy (1998)
    Springer
    Journal of neurology 245 (1998), S. 681-685 
    Details
    ISSN: 1432-1459
    Keywords: Key words Bicycle ergometry ; Coenzyme Q10 ; Lactate ; Lactate/ ; pyruvate ratio ; Mitochondrial ; encephalomyopathies
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We used a standardized bicycle ergometry protocol with a stepwise increasing workload (30–100 W) to evaluate various metabolic factors for the diagnosis and metabolic monitoring of mitochondrial encephalomyopathies. All patients (n = 9) showed pathological venous lactate/pyruvate (L/P) ratios, which normalized in three patients after 6 months of coenzyme Q10 (CoQ) therapy. Thus, the L/P ratio proved to be the clinically most useful parameter in the evaluation and monitoring of mitochondrial diseases, showing higher sensitivity than lactate measurements only. CoQ may exert a favourable effect in some patients with mitochondrial diseases.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004150050267
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  • 3
    Electronic Resource
    Electronic Resource
    Differential expression of tomato (Lycopersicon esculentum L.) genes encoding shikimate pathway isoenzymes. I. 3-Deoxy-D-arabino-heptulosonate 7-phosphate synthase (1993)
    Springer
    Plant molecular biology 23 (1993), S. 697-706 
    Details
    ISSN: 1573-5028
    Keywords: 3-deoxy D-arabino-heptulosonate 7-phosphate synthase ; multi-gene family ; organ-specific expression ; shikimate pathway ; tomato (Lycopersicon esculentum L.)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Tomato (Lycopersicon esculentum L. cv. UC82b) was found to contain two distinct 3-deoxy-D-arabino-heptulosonate 7-phosphate (DAHP) synthase genes that are differentially expressed. The corresponding cDNAs were isolated and characterized. Both genes code for putative plastidic DAHP synthase isoforms. The deduced amino acid sequences are 79% identical. A comparison of the known Solanaceae DAHP synthases indicates two distinct conserved isoforms. The steady-state levels of transcripts of the two tomato genes differ in all organs analysed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00021525
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  • 4
    Electronic Resource
    Electronic Resource
    Cyclisch gekreuzt-konjugierte Bindungssysteme, 41. Sechzehn-Elektronen-Elektrocyclisierung in vinylogen Heptafulvalenen (1983)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 116 (1983), S. 1963-1981 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cyclic Cross-Conjugated Bond Systems, 41, Sixteen-Electron Electrocyclisation of Vinylogous HeptafulvalenesThe vinylogous heptafulvalene 3 easily (Ea=22 ± 1.5 kcal · mol-1, log A=10.8) and perispecifically undergoes the thermal symmetry-allowed conrotatory 16-electron electrocyclisation yielding trans-12a, 12b-dihydrobenzo[1,2:3,4]dicycloheptene (14) (crystal structure analysis). Probably for thermodynamic reasons the analogous 16π-cyclisation in the diazaframe-work 4 (tropone azine) (to 21) proceeds only under acid catalysis. Efforts to identify the tricyclic 16π-annulenes 15/23 have been unsuccessful to date.
    Notes: Das vinyloge Heptafulvalen 3 geht thermisch leicht (Ea=22 ± 1.5 kcal · mol-1, log A=10.8) und perispezifisch die „symmetrieerlaubte“ conrotatorische 16-Elektronen-Elektrocyclisierung zu trans-12a, 12b-Dihydrobenzo[1,2:3,4]dicyclohepten (14) (Röntgenstrukturanalyse) ein. Im Diazagerüst 4 (Troponazin) ist die analoge 16π-Cyclisierung (zu 21) wahrscheinlich aus thermodynamischen Gründen nur unter Säurekatalyse präparativ realisierbar. Die Bemühungen zum Nachweis der tricyclischen 16π-Annulene 15 bzw. 23 blieben erfolglos.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19831160524
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  • 5
    Electronic Resource
    Electronic Resource
    Cyclisch gekreuzt-konjugierte Bindungssysteme, 371) Das vinyloge Sesquifulvalen (1981)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 114 (1981), S. 1679-1696 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cyclic Cross-Conjugated Bond Systems, 371) The Vinylogous SesquifulvaleneAs a model study the tricycloheptenone 8 (“masked tropone”) - obtained from quadricyclanone 7 - is used for the synthesis of the tricyclic fulvene 9, which upon Ag⊕-catalysis or upon direct irradiation is quantitatively isomerized to the highly reactive sesquifulvalene 2. Applying the same scheme to the synthesis of the vinylogous sesquifulvalene 5, the tricyclic aldehyde 16 serves as precursor for the tricyclic fulvene 17, isomeric with 5. 17 is uniformly transformed into 5 in the presence of Ag⊕. The isomeric fulvenes 25 and 26 are exclude as precursors of 5. contrary to literature reports 5 is also obtained from 8-formylheptafulvene but only in very limited yield (max. 10%). 5 can be isolated in crystalline form and shows typical fulvalene-type spectral behavior.
    Notes: In einer Modellstudie wird aus dem Tricycloheptenon 8 (“maskiertes Tropon”) - erhältlich aus Quadricyclanon 7 - das tricyclische Fulven 9 hergestellt, welches unter Ag⊕-Katalyse bzw. unter direkter Belichtung einheitlich zum hochreaktiven Sesquifulvalen 2 isomerisiert. In einem analog konzipierten Zugang zum vinylogen Sesquifulvalen 5 dient der tricyclische Aldehyd 16 als Vor stufe für das mit 5 isomere tricyclische Fulven 17. Die Ag⊕-katalysierte isomerisierung liefert einheitlich 5. Die mit 17 isomeren Fulvene 25 und 26 kommen als Vorstufen für 5 nicht in Frage. In mäßiger Ausbeute (max. 10%) ist 5 entgegen Literaturhinweisen auch aus dem Formylheptafulven 23 erhältlich. Das kristallisiert isolierbare 5 ist durch die Spektren als typisches Fulvalen ausgewiesen.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19811140510
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  • 6
    Electronic Resource
    Electronic Resource
    Cyclisch gekreuzt-konjugierte Bindungssysteme, 381) Vierzehn-Elektronen-Elektrocyclisierung des vinylogen Sesquifulvalens - Phenazulen (1981)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 114 (1981), S. 1697-1722 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cyclic Cross-Conjugated Bond Systems, 381) Fourteen Electron Electrocyclisation of the Vinylogous Sesquifulvalene - PhenazuleneThe vinylogous sesquifulvalene 1 thermally undergoes 14-electron electrocyclisation with ease (Ea = 100 ± 2kj·mol-1, log A = 12.0) and perispecifically. Due to the steric constraints imposed by the system it takes place - almost certainly exclusively - in the “symmetry-forbidden”, conrotatory sense to give trans- 10a, 10b-dihydrophenazulene 2a. This is rapidly isomerized into the benzenoid 1,8- and 3,8- dihydrocyclohept[e]indenes 12/15 and is therefore not directly detectable. The trans-stereochemistry in 2a is verified by x-ray crystal analysis of its 1:1-adduct with dimethyl acetylenedicarboxylate (20). The benzylidenecyclohept[e]indenes 28a-c(obtainable from 12/15) could not be isomerised prototropically to the benzylphenazulenes 30a-c. Treatment of the cation 31 (generated from 28a) with nucleophiles also fails to produce phenazulene derivatives (34). The phenazulenium salts 38/39 are, depending on the counteranion, obtainable from 12 (15) in solution (BF-4, ClO-4) or crystalline (SbCl-6, 1/2 PtCl2-6 EE). From the BF-4 salt a deep-blue compound is generated which is stable below -60°C and in the presence of a large excess of DBN, but polymerises above 0°C or in the presence of SiO2 or Al2O3 (-60°C). It is concluded, that this blue species is phenazulene (3).
    Notes: Das vinyloge Sesquifulvalen 1 geht thermisch leicht (Ea = 100 ± 2kJ. Mol-1, log A = 12.0) und perispezifisch die 14-Elektronen-Elektrocyclisierung ein. Unter dem Zwang der Sterischen Verhältnisse erfolgt diese - sehr wahrscheinlich ausschließlich - im “symmetrieverbotenen”, konrotatorischen Sinn zum trans-10a, 10b-Dihydrophenazulen 2a. Dieses ist wegen der raschen Isomerisierung in die benzoiden 1,8- und 3,8-Dihydrocyclohept[e]indene 12/15 direkt nicht nachweisbar. Die trans-Stereochemie in 2a wird durch Röntgenstrukturanalyse seines 1:1-Addukts mit Acetylendicarbonsäure-dimethylester (20) bewiesen. Die aus 12/15 hergestellten Benzyliden-cyclohept[e]indene 28a-c konnten prototrop nicht zu den Benzylphenazulenen 30a - c isomerisiert werden. Phenazulen-Derivate (34) entstehen auch nicht bei der Umsetzung des aus 28a gewonnenen Kations 31 mit Nucleophilen. Die Phenazulenium-Salze 38/39 sind je nach Gegenion in Lösung (BF-4, CIO-4) bzw. kristallisiert aus 12 (15) herstellbar (SbCl-6, 1/2PtCl2-6). Aus dem BF-4-Salz wird eine bei -60°C und großem DBN-Überschuß beständige, tiefblaue Verbindung freigesetzt, die oberhalb 0°C bzw. im Kontakt mit SiO2O3(-60°C) rasch polymerisiert. Es wird argumentiert, daß es sich hierbei um Phenazulen (3) handelt.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19811140511
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