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  • 1965-1969  (5,155)
  • 1950-1954  (3,508)
  • Organic Chemistry  (5,205)
  • Cell & Developmental Biology  (3,458)
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Year
  • 101
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 174-177 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
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  • 102
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 183-186 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
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  • 103
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 178-182 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
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  • 104
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 187-189 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
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  • 105
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969) 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 106
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 190-192 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 107
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 193-200 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wird eine Reihe von Theophyllinderivaten beschrieben, welche zu den Diphenylpropylaminen gehören.
    Type of Medium: Electronic Resource
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  • 108
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 213-218 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 1-Acyl-5-[(3-phenyl)-1.2.4-triazolyl-(5)]-diaminoguanidine sowie 1-Benzoyl-5-[(3-phenyl)-1.2.4-thiodiazolyl-(5)]- und 1-Benzoyl-5-[pyridyl-(4)]-diaminoguanidin cyclisieren in siedender Alkalilauge durch intramolekulare Wasserabspaltung und gleichzeitige Oxydation durch Luftsauerstoff zu in Nβ-Stellung durch Heterocyclen substituierten 3-Aryl(alkyl)-5-azo-1.2.4-triazolen, die durch Zinn (II)-chlorid in saurem oder durch Natrimdithionit in alkalischem Milieu zu den korrespondierenden Hydrazoverbindungen reduziert werden können.
    Additional Material: 1 Tab.
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  • 109
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 201-212 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Die Temperaturabhängigkeit des endo/exo-Isomerenverhältnisses bei der Umsetzung von Cyclopentadien mit Acrolein wird untersucht; in dieser kinetisch kontrollierten Reaktion fällt der Gehalt an endo-Form von 76% bei 20°C (in Dioxan) auf 71% bei 101°C. Für die Bildung der endo-Form wird bei etwa gleicher Aktivierungsentropie eine geringere Aktivierungsenthalpie benötigt (ΔΔH≠ 650 cal/Mol). Beim Erhitzen von 2,5-Methylen-1,2,5,6-tetrahydrobenzaldehyd 1 erfolgt Isomerisierung, wobei der Gleichgewichtswert bei 170°C nach wenigen Stunden erreicht wird; unter 100° bleibt die Ausgangszusammensetzung erhalten.Die Äquilibrierung mit Basen liefert den Gleichgewichtswert bereits nach wenigen Minuten: Kexo/endo = 0,695 (20°C); 0,925 (100°C). Die Basenkonzentration muß niedrig sein. da beim Aldehyd 1 leicht CANNIZZARO-Reaktion eintritt.Äquilibrierungsversuche mit Säuren schlugen infolge Nebenproduktbildung fehl.Durch alkalische Hydrolyse des Enolacetats 5 wird das thermodynamisch, durch saure Spaltung von 5 sowie des Enoläthers 6 oder der Enamine 7 wird das kinetisch bestimmte endo/exo-Verhältnis (∼ 75/25) erhalten.Reaktivitätsunterschiede der beiden Formen des Aldehyds 1 machen sich nicht bemerkbar.
    Additional Material: 5 Tab.
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  • 110
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 219-227 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis, some dyeing, and fastness properties of several new dispersed and acid dyes derived from the amino-benzotriazoles 1 & 3 and the aminobenzimidazoles 2a, 2b & 4 are described. The suitability of the amino derivatives 1, 2a, 2b, 3 & 4 as bases for azoic dyeing has also been studied. Several interesting observations between the properties of some synthesised dyes and the corresponding benzene or naphthalene analogues are cited.
    Additional Material: 6 Tab.
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  • 111
    Electronic Resource
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    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 228-230 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Durch Auswertung der IR-Spektren einiger substituierter Schwefelsäurediamide konnten für die SO2-Gruppe dieser Amide folgende Moleküldaten nach GILLESPIE berechnet werden: Bindungsabstand, Bindungswinkel, Kraftkonstante sowie Bindungsabstand.
    Additional Material: 3 Tab.
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  • 112
    Electronic Resource
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    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 231-237 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Benzylhydrazin reagiert analog dem Phenylhydrazin und im Gegensatz zu aliphatischen Hydrazinen mit in 5-Stellung substituierten 2-Amino-1,3,4-oxdiazolen zu Diamino-guanidinen, die sich zu 1,2,4-Triazolen cyclisieren lassen.
    Additional Material: 6 Tab.
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  • 113
    Electronic Resource
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    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 256-259 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es werden neue Methoden zur Herstellung von phosphororganischen Isocyanaten durch Umsetzung von phosphororganischen Amidsalzen mit Phosgen oder Oxalylchlorid und aus N-Diphenyl-phosphinsäureureiden mit Phosgen beschrieben. Phosphonsäurediureide liefern mit Phosgen Dioxo-triazaphosphorinane.
    Type of Medium: Electronic Resource
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  • 114
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 260-265 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Drei in 2,6-Stellung des aromatischen Kernes disubstituierte β-Methylstyrole wurden mit NOCl/HCl in α-Chloroxime überführt; diese lieferten mit Triäthylamin in Äther relativ stabile monomere Nitrosoolefine, die durch ihre Spektren sowie durch ihre Reaktion mit Piperidin zu α-Piperidinooximen charakterisiert wurden.
    Additional Material: 5 Tab.
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  • 115
    Electronic Resource
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    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 238-255 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Die Additionen von Jodthiocyanat (JSCN), 2,4-Dinitrobenzolsulfenylchlorid (ArSCl) und Nitrosylchlorid (NOCl) an Olefine verschiedener Strukturtypen wurden teils durch maßanalytische Verfolgung der Konzentrationen, teils durch gaschromatographische Auswertung von Konkurrenzreaktionen kinetisch untersucht. Die Reaktionen sind untereinander und mit der Brom-Addition verwandt. Die Additionsgeschwindigkeiten von JSCN, ArSCl und NOCl an kernsubstituierte Styrole geben eine gute Korrelation mit der HAMMETT-Gleichung, die Additionsgeschwindigkeiten an offenkettige aliphatische Olefine folgen der TAFT-Gleichung befriedigend. Die relativen Reaktionsgeschwindigkeiten von cis/trans-isomeren Olefinen sowie die von Cycloolefinen werden diskutiert. Offenbar läßt sich aus kinetischen Daten allein nicht sicher ableiten, ob der Übergangszustand elektrophiler Olefin-Additionen einem offenkettigen Carbeniumion, einem verbrückten. Ion oder einem Vierring ähnlich ist. Die Additionsgeschwindigkeiten von Quecksilberacetat (Hg(OAc)2) an Olefine zeigen eine völlig andere Abhängigkeit von der Struktur des Substrats als die Additionsgeschwindigkeiten von Br2, JSCN, ArSCl und NOCl.
    Additional Material: 5 Ill.
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  • 116
    Electronic Resource
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    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 266-270 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction of glutaric anhydride with benzene and toluene has been thoroughly studied. 4,4-Diphenyl-pent-4-enoic acid and 1,3-dibenzoyl propane were isolated as by-products of the reaction with benzene. The mechanism of formation of the by-products has been proved. In case of toluene no by-products were detected.
    Additional Material: 2 Ill.
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  • 117
    Electronic Resource
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    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 271-277 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Durch Umsetzung der beiden Tripeptid-Derivate Boc - Gly - Ile - Cys(Bzl) - Azid und Ser - Leu - Tyr - OMe [3] wird das geschützte Hexapeptid Boc - Gly - Ile - Cys(Bzl) - Ser - Leu - Tyr - OMe erhalten. Dieses Peptid entspricht der Aminosäuresequenz 9-14 der A-Kette des Pferdeinsulins.
    Type of Medium: Electronic Resource
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  • 118
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    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 278-285 
    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 Pentapeptid-Derivates Boc - Dab(Z) - D - Leu - Ile - Dab(Z) - Dab(Z) - NHNH2 [2] beschrieben. Es entspricht einer Teilsequenz der bisher für das Circulin B angenommenen Struktur. Der Aufbau erfolgte stufenweise vom Carboxylende her unter Benutzung der Nitrophenylester und der gemischten Anhydride.
    Additional Material: 1 Tab.
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  • 119
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    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 296-301 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: An 12 Alkylcycloheptanonen wurde die Verschiebung der Protonensignale im Kernresonanzspektrum beim Übergang vom Lösungsmittel CDCl3 zu C6H6 untersucht. Die erhaltenen Ergebnisse lassen sich zur Konformation der Cycloheptanone in Beziehung setzen und weisen auf das Vorliegen dieser Verbindungen als axialsymmetrische Sesselkonformation hin.
    Additional Material: 1 Tab.
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  • 120
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    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 286-295 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Das neuerdings leicht zugängliche 3-Amino-4-hydroxy-6-methy1-pyridazin 1 [1] erschließt einen neuen Zugang zu Derivaten des Pyridazins. Die Umsetzung mit salpetriger Säure liefert in verdünnter Schwefelsäure 3,4-Dihydroxy-6-methyl-pyridazin 3, in konz. Salzsäure dagegen 3-Chlor-4-hydroxy-6-methylpyridazin 2. Das Chloratom in 2 ist leicht nucleophil ersetzbar unter Bildung der 3-Hydroxy-, 3-Amino- bzw. 3-Phenylthio-Verbindungen 3, 7a-i. Noch leichter reagieren die entsprechenden 4-Methoxyverbindungen, so daß auch die interessanten3-Arylsulfonylamino-4-methoxy-Derivate 8k, l gut zugänglich sind.Mit Phosphoroxidchlorid liefert 2 das 3,4-Dichlor-6-methyl-pyridazin 10, das - ebenso wie 2 - in Gegenwart von Palladium reduktiv enthalogeniert werden kann, wobei 3-Methyl-pyridazin 11 bzw. das bisher unbekannte 4-Hydroxy-6-methyl-pyridazin 9 entstehen. Die Umsetzung des 3-Amino-4-hydroxy-6-methyl-pyridazins 1 mit Dimethylsulfat führt nur zum 4-Methoxy-Derivat 4. In gleicher Weise reagieren die 4-Hydroxy-6-methylpyridazine 7a-i und 2. Die Struktur der dargestellten Verbindungen wird gesichert. Die Verbindungen mit 4-Hydroxygruppe zeichnen sich durch hohe Schmelzpunkte, relativ geringe Löslichkeiten in Wasser und damit zusammenhängend sehr stark assoziierte IR-Banden der OH-Gruppe aus.
    Additional Material: 1 Tab.
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  • 121
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    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 328-335 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Preliminary studies on the different chelates of PGR and BPGR with a number of metal ions have been made. Different conditions under which these chelates are formed have been evaluated.
    Additional Material: 6 Ill.
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  • 122
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    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 302-327 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Nickel cyanide-ammonia forms clathrate compounds with a variety of organic molecules such as aniline, benzene, pyridine, pyrrole, and thiophene. The present results suggest that there is a definite indication of captured molecules and the absorption characteristics of molecules in their environment in nickel cyanide-ammonia cage are similar to those of the molecules in liquid state. In accepting the guest molecules, the nickel cyanide-ammonia structure is not changed, since apart from the appearance of bands due to the trapped molecules, the bands due to pure nickel cyanide-ammonia remain virtually unchanged. The infrared spectra of nickel cyanide-ammonia clathrates in the 100-4000 cm-1 region are described in this investigation.
    Additional Material: 26 Ill.
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  • 123
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    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 336-349 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 7 Tab.
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  • 124
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    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 350-352 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 3 Tab.
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  • 125
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    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969) 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 126
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    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 363-369 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Bei der Umsetzung von 3-Methylpyrazol-5-carbonsäureäthylester mit Dialkylaminoalkylhalogeniden entstehen Isomerengemische der 1,3- und 1,5-dialkylierten Ester. Bei der α-Aminomethylierung erhält man ausschließlich den 1,5-dialkylierten Ester.
    Additional Material: 1 Ill.
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  • 127
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 353-362 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Verschiedene Cyanacetylamino-Verbindungen wurden mit p-Nitroso-N.N-bis-(β-chloräthyl)-anilin und p-Nitroso-N.N-bis-(β-hydroxyäthyl)-anilin zu den entsprechenden Cyananilen umgesetzt. Bromcyanacetamid lieferte analoge Nitrone. Aus Cyanacetylverbindungen, deren Amidsubstituent in einer zum Ringschuluß geeigneten Stellung ein reaktionsfähiges H-Atom besitzt, bildeten sich unter HCN-Abspaltung Anile cyclischer Verbindungen.
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  • 128
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 370-378 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Carbonsäureester R—CH2—COOMe werden durch MeONO/NaOMe in aprotischen Lösungsmitteln α-nitrosiert; man erhält in Ausbeuten zwischen 14 und 34% die entsprechenden α-Oximinocarbonsäureester. α-Verzweigte Carbonsäureester werden durch MeONO/NaOMe nitrosierend gespalten: Die primär gebildeten Ketoxime lassen sich wegen des Auftretens von Folgereaktionen nur in Ausbeuten unter 10% isolieren.
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  • 129
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 379-382 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Die aus 2-Oxolävulinsäureäthylester mit Aminen und Aldehyden gebildeten 3-Acetyl-4.5-dioxopyrrolidine 1 reagieren mit Arylhydrazinen zu entsprechenden 6-Oxo-1.4.5.6-tetrahydropyrrolo[3.4-c]pyrazolen 2.
    Additional Material: 1 Tab.
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  • 130
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 438-444 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Aus 1-Methyl-7-amino-6-azalumazinen werden substituierte 3,5-Diamino-as-triazin-carbonsäuren-6 dargestellt. Durch Erhitzen über den Schmelzpunkt entstehen daraus substituierte Diamino-as-triazine. Die alkalische Verseifung von 1-Methyl-7-äthylmercapto-6-azalumazin ergab 1-Methyl-7-hydroxy-6-azalumazin.
    Additional Material: 2 Tab.
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  • 131
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Bei 25°C wurden an den binären Systemen Methanol/Dimethylformamid, Aceton/Dimethylformamid, Äthanol/Diäthylformamid und Aceton/Diäthylformamid mittlere molare Zusatzenthalpien und mittlere molare Zusatzvolumina bestimmt. Die kalorimetrischen Messungen erfolgten vorwiegend im mittleren, die pyknometrischen im gesamten Molenbruchgebiet. Die experimentell gefundenen Zusatzeffekte ergaben sich bei äquimolarer Zusammensetzung in der genannten Reihenfolge der Systeme wie folgt: -26,5; +8,8; +72,5; +10,2 cal/Mol bzw. -0,385; -0,26; -0,095 und +0,036 cm3/Mol. Ihre Konzentrationsabhängigkeiten zeigten schwache bis mäßige Asymmetrie.Diese Ergebnisse führten zusammen mit früher ermittelten molaren freien Zusatzenthalpien zu qualitativen Modellvorstellungen über molekularstrukturell bedingte Nahordnungszustände in den vier Mischphasen.
    Additional Material: 4 Ill.
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  • 132
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 445-454 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wird die Synthese von 6-Azido- und 6-Amino-17 α-acetoxy-progesteron und von 6-Azido- und 6-Amino-testosteronacetat beschrieben. Die Einführung der Stickstoffunktion kann durch Aufspaltung des entsprechenden Epoxides mit Natriumazid erfolgen. Die Aminoverbindungen werden aus den Azidoverbindungen durch Reduktion mit Hydrazinhydrat/Raney-Nickel erhalten.
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  • 133
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 455-462 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Bei der Umsetzung von Caprolactam mit Sulfurylchlorid in CCl4 wird ein bicyclisches, chlorhaltiges Amidin (1-[3,3-Dichlor-azacyclohepten-(1)-yl (2)]-2-oxo-3,3-dichlorazacycloheptan) 2 gebildet, dessen Struktur durch NMR-Spektroskopie aufgeklärt wurde. Die Bildungsweise von 2 aus Caprolactam, α, α-Dichlor-caprolactam und dem bisher als Dicaprolactimäther bezeichneten 1-[Azacyclohepten-(1)-yl-(2)]-2-oxo-azacycloheptan 5 wurde untersucht.
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  • 134
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 463-471 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wird über die Reaktionen von Bi- und Cyclopoly-phosphinen mit P-substituierten Lithiumphosphiden berichtet. Die Umsetzung von Tetraphenylbiphosphin mit LiPR2 (R = C2H5; c-C6H11) und Li2PR′ (R′ = C6H5) führt zunächst zu unsymmetrischen Biphosphinen R′2P-PR2 bzw. R′(Li)P-PR′2, die mit weiterem LiPR2(Li2PR′) die symmetrischen Biphosphine R2P-PR2 bzw. R′(Li)P-P(Li)R′ bilden. Aus „Phenylphosphor“ und Li2PC6H5 entstehen Verbindungen des Typs Li-(PC6H5)x-Li (x = 2, 3, 4). Versuche, Lithium-phosphide der Zusammensetzung Li-(PC6H5)x-P(C6H5)2 (x 〉 1) aus „Phenylphosphor“ und Lithium-diphenylphosphid herzustellen, blieben ohne Erfolg. Es gelang nur, ihre Zerfalls- bzw. Abbauprodukte 1.4-Dilithium-1.2.3.4-tetraphenyl-tetraphosphin, Tetraphenylbiphosphin und 1-Lithium-1.2.2-triphenylbiphosphin zu isolieren.
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  • 135
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 472-476 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Die Anwendbarkeit der jodometrischen Titration zur Bestimmung von Enthiolgehalten einiger Thiocarbonylverbindungen wird geprüft. Verläßliche Ergebnisse lassen sich nur bei völlig wasserfreier Arbeitsweise erzielen, anderenfalls wird ein Enthiolgehalt nur vorgetäuscht. Die Endpunktsanzeige kann optisch oder besser potentiometrisch erfolgen. Rücktitrationsverfahren mit wäßrigen Lösungen sind ungeeignet. Beim potentiometrischen Verfahren vermögen einige CH-acide Thion- und Dithioester mit basischen Leitsalzen Enthiolate zu bilden, die wie freie Enthiole reagieren, weshalb die Methode bei diesen Verbindungen nicht brauchbar ist.
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  • 136
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    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 137
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969) 
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    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 138
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 527-528 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Tab.
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  • 139
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 529-538 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Die Umsetzung von Äthylendiamin mit Chlormethylphosphonat in alkalischem Medium führte zur Bildung von β-Aminoäthyl-aminomethylphosphonsäure 1, Äthylendiamin-N,N′-di(methyl-phosphonsäure) 2, Äthylendiamin-N,N,N′-tri(methylphosphonsäure) 3 und Äthylendiamin-N,N,N′,N′-tetra(methylphosphonsäure) 4. Durch potentiometrische pH-Titration wurden die pK-Werte der Säuren 1 bis 4 bestimmt. Aus den pK-Werten wurden Dissoziationsschemata abgeleitet und mit denen von Aminopolycarbonsäuren verglichen.
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  • 140
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 539-548 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Bei der Einwirkung von Hydrazinhydrat auf 2-Arylamino-5-alkyl-1,3,4-oxdiazole entstehen neben 3-Alkyl-4-aryl-s-triazolonen-(5) 4 die 3-Alkyl-4-amino-5-arylamino-s-triazole 3, deren Eigenschaften untersucht werden.
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  • 141
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 563-570 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wird über die Darstellung von α-trimethylammoniumsubstituierten Phosphonaten 2 berichtet. In Abhängigkeit von der Nucleophilie des Anions und der Natur des Phosphonat-alkyls geben sie mehr oder weniger glatt Alkyl-phosphonobetaine 3. Durch Deprotonierung entstehen aus 2 stabile N-Ylide 4, deren Struktur durch Kernresonanz-Spektroskopie eindeutig sichergestellt werden konnte.
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  • 142
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 571-576 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Aus Phosphortrichlorid und verschiedenen Orthoameisensäureestern bzw. Orthopropionsäureester wurden Dialkoxyalkanphosphonsäuredialkylester 2 bzw. 3 gewonnen. Phosphorigsäure-dialkyl- bzw. -diphenyl-ester-chloride reagieren mit Orthoameisensäureester zu Diäthoxymethanphosphonsäureestern mit verschiedenen Substituenten an Phosphor und Kohlenstoff (4), Phosphorigsäure-alkyl-bzw. -arylester-dichloride analog zu Derivaten mit verschiedenen Resten am Phosphor (10). Cyclische Phosphorigsäureester-chloride geben neben ringoffenen Phosphonsäureestern hauptsächlich höhermolekulare Produkte.
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  • 143
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    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Thiokohlensäure-S-ester-N-(β-chloralkyl)-imidchloride, die bei der Chlorierung von Olefinen in Gegenwart von Alkylthiocyanaten entstehen, werden mit Alkalialkoholaten und Alkalimercaptiden zu N-(β-Chloralkyl)-imino-thiokohlensäureestern bzw. -imino-dithio-kohlensäureestern umgesetzt. Behandelt man obige Imidchloride mit Natriumhydrogen-sulfid, so erhält man 2-Alkylmercapto-Δ2-thiazoline; mit primären Aminen entstehen 2-Alkylmercapto-Δ2-imidazoline.Die analog bei der Chlorierung von Olefinen im Beisein von Dialkylcyanamiden erhaltenen N-(β-Chloralkyl)-N′,N′-dialkyl-isoharnstoffchloride geben bei der Umsetzung mit Wasser oder Alkoholen 2-Dialkylamino-Δ2-oxazoline, mit Natriumhydrogensulfid 2-Dialkylamino-Δ2-thiazoline und mit primären Aminen oder Ammoniak 2-Dialkylamino-Δ2-imidazoline.
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  • 144
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 577-585 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Aus Dimethylformamiddimethylacetal (3) und Phosphorigsäuredialkylestern bzw. sek. Phosphinoxiden sind Bis-phosphono- bzw. -phosphinyldimethyl-amino-methane (8 bzw. 14) zugänglich. 8 entsteht auch aus Phosphorigsäure-trialkylestern und Dimethylformamid-dichlorid. Bei der Reaktion von Phosphorigsäuredialkylestern mit Dimethylformamid-dithioacetalen sind α-di-substituierte Phosphonsäureester zugänglich, die sich entweder in 8 oder in Phosphinyl-phosphonsäureester umwandeln lassen.
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  • 145
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 643-645 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Die Korrelation zwischen dem Aktivitätskoeffizienten des Wassers fH2O in 1.4-Dioxan-Wasser-Gemischen und der relativen chemischen Verschiebung der Wasserprotonen im NMR-Spektrum ΔδH2OD läßt sich für nahezu den gesamten Molenbruchbereich bei den Temperaturen 25°, 35° und 87° mit hinreichender Genauigkeit durch die Beziehung 1/√lgfH2O = k/ΔδH2OD + k′ beschreiben.
    Additional Material: 2 Ill.
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  • 146
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 786-799 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Aminofumarsäuredialkylester und 2-Amino-3-acetyl-acrylsäureäthylester reagieren mit p-Benzochinon in Eisessig zu 3-Amino-6-hydroxy-4-alkoxycarbonyl- (bzw. -4-acetyl-) cumarin 1 bzw. 15. N-monosubstituierte Aminofumarsäuredialkylester liefern unter sonst gleichen Bedingungen meist ebenfalls das N-unsubstituierte 3-Amino-6-hydroxy-4-alkoxy-carbonyl-cumarin 1 bzw. das 3,6-Dihydroxy-4-alkoxycarbonyl-cumarin 12. In Abhängigkeit von den Ausgangsprodukten findet man darüber hinaus Benzofurane, Benzo[1.2-b; 4.5-b′]difurane und Benzo[1.2-b; 4,5-b′]dipyrone. Aus 2-Amino-3-benzoyl-acrylsäureäthylester entsteht mit p-Benzochinon in guten Ausbeuten 5-Hydroxy-3-benzoyl-2-äthoxycarbonyl-indol 19.
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  • 147
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    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Aminofumarsäurediäthylester reagiert mit p-Benzochinon in Gegenwart äquimolarer Mengen Bortrifluorid unter thermodynamischer Kontrolle zum 3-Amino-6-hydroxy-4-äthoxycarbonyl-cumarin 2; die kinetisch kontrollierte Reaktion liefert das 3,6-Dihydroxy-4-äthoxycarbonyl-cumarin 3a. N,N-disubstituierte Aminomaleinsäuredimethylester bilden mit p-Benzochinon sowohl in Eisessiglösung ohne Katalysator als auch mit Bortrifluoridätherat in Diäthyläther das 2,3,6,7-Tetramethoxycarbonyl-benzo[1.2-b; 4.5-b′]difuran 5, bei den bortrifluoridkatalysierten Umsetzungen lassen sich Zwischenprodukte der Reaktion isolieren.
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  • 148
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 807-815 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Aus Isopropylaminofumarsäure-dimethylester und p-Benzochinon erhält man in Gegenwart von Zinkchlorid 3-Amino-6-hydroxy-4-methoxycarbonyl-cumarin 1 b, mit Cyclohexylaminofumarsäure-dimethylester sind 3-Cyclohexylamino-6-hydroxy-4-methoxycarbonyl-cumarin 8, 3,8-Dicyclohexylamino-4,9-dimethoxycarbonyl-benzo [1.2-b; 4.5-b′] dipyron-(2,7) 9 und 5-Hydroxy-1-cyclohexyl-2,3-dimethoxy-carbonyl-indol 4 h zugänglich. In Gegenwart von Bortrifluoridätherat bilden sich hingegen aus N-monosubstituierten Aminofumarsäure-dimethylestern und p-Benzochinon immer 1-substituierte 5-Hydroxy-2,3-dimethoxycarbonyl-indole 4, die sich über die Dicarbonsäuren 6 in die 1-substituierten 5-Hydroxyindole 7 überführen lassen.
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  • 149
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 912-918 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reaktion von 3β-Acetoxy-16α, 17α-epoxy-Δ5-pregnenon-(20) 1 mit Natriumazid und Schwefelsäure in Dimethylsulfoxid führt zu 3β-Acetoxy-16β-azido-17α-hydroxy-17β-methyl-D-homo-Δ5-androstenon-(17a) 2a. Die Strukturaufklärung der Verbindung 2a wird beschrieben. Durch Reduktion der Azidogruppe mit Hydrazinhydrat/RANEY-Nickel werden Aminoverbindungen erhalten. Die Überführung der 3β-Acetoxy-Δ5-16β-azido- und -aminoverbindungen in die entsprechenden 3-Keto-Δ4-Derivate wird beschrieben.
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  • 150
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 919-924 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reaktion von 6,7α-Epoxy-17α-acetoxy-progesteron 1 mit Natriumazid in Äthylenglykolmonomethyläther führt zu 6β-Azido-7α-hydroxy-17α-acetoxy-progesteron 2a, das durch Säuren zu 6-Azido-17α-acetoxy-Δ4,6-pregnadien-dion-(3,20) 3 dehydratisiert wird. Durch Reduktion des Azidoalkohols 2a werden 6-Amino-Derivate des 17α-Acetoxy-progesterons erhalten.
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  • 151
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 925-929 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: O,N-Acetale 1 des bisher unbekannten Formylphosphonsäureesters wurden aus Phosphorigsäuredialkylester und Dimethylformamidacetal bzw. aus Na-Phosphorigsäuredialkylester und Dimethylformamid-Dimethylsulfat-Komplexen dargestellt. 1 ist entweder direkt oder über die hieraus mit thionylchlorid erhältlichen Immoniumsalze 4 in Bis-phosphonsäureester 5 überführbar.Aus Tetramethylformamidinium-methylsulfat und Na-Phosphorigsäuredialkylester wurde das N,N-Acetal 9 des Formylphosphonsäureesters dargestellt.
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  • 152
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 930-935 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Trichlormethyl-trifluorsilan wurde mit Antimon(III)-fluorid. Diphenylantimon(III)-fluorid, Triphenylbleifluorid und Phenylquecksilberacetat umgesetzt. Unter Abspaltung von SiF4 bildeten sich meist unbeständige Trichlormethylmetallverbindungen, die in die entsprechenden Schwermetallchloride übergingen. In reiner Form konnten Trichlormethyl-diphenylantimon(III) 2 und Trichlormethyltriphenylblei 3 abgetrennt werden.
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  • 153
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 936-941 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 1-Acylsemicarbazide reagieren in Dimethylsulfoxid/Kaliumhydroxid mit molekularem Sauerstoff unter Abspaltung von Stickstoff, Kohlenmonoxid und Wasser zu N-substituierten Carbonsäureamiden. Die Umsetzung verläuft wahrscheinlich über die Zwischenstufe der instabilen Azoverbindungen. Durch ein Kreuzungsexperiment wurde festgestellt, daß die Carbonsäureamidbildung zumindest teilweise intermolekular über Bruchstücke erfolgt.
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  • 154
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 970-973 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A description is given of the preparation of tetra(2-chloro)ethoxysilane 1 from tetrachlorosilane and ethylene oxide, also by the alcoholysis of tetraethoxysilane with 2-chloroethanol. Some physical properties of 1 have been determined. Cryoscopic molecular weight determinations in benzene solution showed 1 to be monomeric in this solvent over a wide concentration range. The alcoholysis of 1 with n-heptanol gave, as expected, tetra-n-heptyloxysilane 2.
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  • 155
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 958-969 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polymere, die gleichzeitig 1,1′-Ferrocenylengruppen und 1,3,4-Oxadiazolringe in der Kette enthalten, wurden durch Reaktion von Dicarbonsäuredichloriden mit Bis-tetrazolen in Pyridin oder N,N-Diäthylanilin und durch chemische Cyclodehydratisierung von Poly-(acylsemicarbaziden) mittels Phosphoroxychlorid dargestellt. Die relativ geringe thermische Stabilität dieser Polymeren ist sowohl auf die Unbeständigkeit des substituierten Ferrocens als auch auf die Instabilität der mit Ferrocen substituierten 1,3,4-Oxadiazolringe zurückzuführen, wie durch Untersuchungen an einer von uns für diesen Zweck synthetisierten oligomeren Verbindung vom Molekulargewicht 1086 festgestellt wurde.
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  • 156
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 983-992 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Durch Protonenresonanzmessungen an Steroiden mit der Äthylendioxy-Gruppe an den C-Atomen 3, 6, 17 und 20 am Cyclohexanon- und Acetonketal in nichtaromatischen und aromatischen Lösungsmitteln werden spektroskopische Charakteristika der Ketalgruppe erhalten. Die „long-range“-Wirkungen der Ketalgruppe auf die angulären Methylgruppen des Steroids, verursacht durch die magnetische Anisotropie und das elektrische Dipolmoment dieser Gruppe, werden theoretisch in relativ guter Übereinstimmung mit den experimentellen Werten ermittelt. An der polaren Ketalgruppe werden in Benzollösung Anlagerungskomplexe gebildet, wobei das π-Elektronensystem des Benzols mit der partiell positiven Seite der Ketalgruppe in Wechselwirkung tritt. Die Breite des Protonenresonanzbereiches der Ketalgruppe, ebenfalls abhängig vom Lösungsmittel, gibt Auskunft über benachbarte Substituenten.Die chemischen Verschiebungen und Kopplungskonstanten der Ketalprotonen selbst erscheinen nicht geeignet, die Stellung der Ketalgruppe im Steroid eindeutig zu bestimmen.
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  • 157
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 383-387 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of oxidation of phenylacetic acid by chromic acid in sulphuric acid medium has been carried out. Acetic acid has been observed to enhance the oxidation rate. A mechanism consisting of electrophilic attack of the oxidant on the substrate has been suggested.
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  • 158
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 388-394 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Diazoessigester und Diazoketone addieren sich basenkatalysiert an Alkylidenmalonitrile unter Bildung von 1,2-Diamino-3-cyan-pyrrol-Derivaten, die sich leicht zu Pyrrolo-[1,2-b]-as-triazinen cyclisieren. - 2-Cyan-3-methyl-zimtsäureäthylester liefert dagegen mit p-Nitrophenyl-diazomethylketon 2-p-Nitrophenacyl-4-cyan-5-phenyl-pyridazinon-(3).
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  • 159
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 395-401 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Geeignet substituierte α-Aminophosphonate 3 bzw. 7 lassen sich mit Aldehyden bzw. mit Glyoxylsäurepiperidid in α- bzw. β-aminosubstituierte Acrylsäurederivate überführen. Durch Hydrolyse entstehen hieraus die entsprechenden Derivate von α- bzw. beta;-Ketocarbonsäuren. 3 a gibt mit Nitrosobenzol das Oxalsäureester-amidin 6 a.
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  • 160
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 402-407 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Cyclohexanon und -heptanon reagieren basenkatalysiert mit Schwefel und Cyanacethydrazid bzw. N-Acetylcyanacethydrazid zu Thieno[2,3-d]pyrimidon-Derivaten, die sich zu 2-Amino-thiophencarbonsäure-(3)-hydraziden hydrolysieren lassen, während das aus Cyclopentanon, Acetylcyanacethydrazid und Schwefel erhältliche substituierte Aminothiophencarbonsäurehydrazid leicht zu einem 3-Amino-thieno[2,3-d]pyrimidon cyclisiert.
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  • 161
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 408-419 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Läßt man auf N-(β-Haloalkyl)-imidhalogenide, die bei der Reaktion von Olefinen mit Halogenen in Gegenwart von Nitrilen neben den vic-Dihalogenalkanen entstehen, Wasser, Schwefelwasserstoff, Ammoniak oder primäre Amine in alkalischem Medium einwirken, so erhält man in praktisch einstufiger Synthese Δ2-Oxazoline, Δ2-Thiazoline oder Δ2-Imidazoline. Die Reaktionsschritte verlaufen stereospezifisch. Bei Verwendung von Δ1-Olefinen ist in den Δ2 -Azolinen neben dem 4-substituierten Hauptprodukt (Markownikow-Addition) auch die 5-substituierte Verbindung (anti-Markownikow-Addition) zu 5-10% enthalten.
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  • 162
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 429-437 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In einer modifizierten Umlaufapparatur nach GILLESPIE wurden Flüssigkeit-Dampf-Gleichgewichte der Systeme n-Butanol/sek.-Butanol und n-Butanol/tert.-Butanol isobar bei 100, 300, 500 und 700 Torr im gesamten Molenbruchbereich gemessen.Aus den Experimentaldaten wurden unkorrigierte Aktivitätskoeffizienten berechnet und mit Hilfe der Beziehungen von LI und COULL approximativ dargestellt. Für beide Systeme konnten geringe aber eindeutig nachweisbare negative Abweichungen vom idealen Mischungszustand festgestellt werden. Die Meßwerte erfüllten die thermodynamische Konsistenzbedingung nach HERINGTON befriedigend. Die thermodynamischen Zusatzeigenschaften deuten die Bildung von Mischassoziaten in beiden Systemen an.
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  • 163
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 769-774 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Spectrophotometric study has been made with a view to investigate the composition and stability of the chelate formed between uranium(VI) and penta sodium salt of Methylthymol Blue (MTB). The composition of the red coloured chelate (λmax510 nm) as established by two different methods, comes out to 1:1 (metal:chelating agent). The chelate is stable between pH 6.2 and 6.9. The average value of log K at 30° (pH 6.7 ± 0.1; μ = 0.1 M) is 5.6 ± 0.2 and ΔG° at the same temperature is -7.7 ± 0.2 kcal/mole.
    Additional Material: 6 Ill.
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  • 164
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 775-785 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Durch Kombination von kinetischen Messungen und Konkurrenzreaktionen wird nachgewiesen, daß die sehr schnelle Substitution des Halogens in α-Halogenhydroxamsäuren durch basische Nucleophile nach einem Eliminierungs-Additions-Mechanismus verläuft. Bei der Umsetzung von α-Chlorhydroxamsäurechloriden mit Methanol in Gegenwart von CaCO3 werden nicht α-Chlorhydroxamsäuremethylester, sondern α-Methoxyhydroxamsäurechloride gebildet.
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  • 165
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 816-826 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Quecksilber und m,m′-Dimethyldithizon bilden zwei Chelatkomplexe, die sich durch ihre Farbe und ihr Molverhältnis unterscheiden.Die Stabilität der beiden Quecksilber-m,m′-dimethyldithizonate wird durch den pH-Wert und das Extraktionsmittel unterschiedlich beeinflußt.Die neuen Quecksilberverbindungen wurden auf ihre analytische Verwendbarkeit untersucht.
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  • 166
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 827-843 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Die neuartigen 2-bzw. 3-Dialkylamino-thiophene 5 und 6 sowie die 2-Dialkylamino-thionaphthene 7, jedoch nicht die 3-Dialkylamino-thionaphthene, resultieren durch Umsetzung von entsprechenden Mercapto-thiophenen mit sekundären Aminen. Die mit dem Dimethylanilin isosteren 5 und 6 sind unter milden Bedingungen leicht elektrophil substituierbar, wobei die Umsetzungen mit Carbonylverbindungen zu tieffarbigen kationoiden Methinverbindungen oder zu Formylderivaten führen. Dagegen liefert die Umsetzung mit Alkylierungsmitteln Quaternierungsprodukte. Zur Strukturermittlung der synthetisierten Verbindungen werden chemische, spektroskopische sowie quantenchemische Kriterien herangezogen.
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  • 167
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wird über die Umsetzungen der Bis-trimethylsiloxy-alkene mit Formamid zu Imidazolen, mit Harnstoff zu Imidazolinonen-(2), mit Thioharnstoff zu Imidazolinthionen-(2), mit β-Aminocrotonester zu 2-Methyl-3-carbäthoxy-pyrrolenund mit Malodinitril zu 2-Amino-3-cyano-furanen berichtet.
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  • 168
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 851-856 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Die gleichzeitige Einwirkung von 1,2-Dibrompropionsäuremethylester und Iminodiessigsäure auf Alkalicellulose führt zu einem Cellulosederivat mit komplexbildenden α(β)-Alanin-N,N-diessigsäure-Ankergruppen. Das Produkt wurde auf sein Austauschvermögen untersucht und die Kapazitäten für Metallionen bestimmt.
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  • 169
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 857-868 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Triphenyl-allylen-phosphoran (A) reagiert mit Dialkyl- bzw. Diarylchlorphosphin und Aryldichlorphosphin unter nucleophiler Substitution in γ-Stellung und intermolekularer Umylidierung zu Triphenyl-allylen-phosphoranen des Typs bzw. Unter gleichen Bedingungen setzt sich Phosphortrichlorid mit A nur zu einem Phosphoniumsalzgemisch um, das mit NaNH2 in das entsprechende Ylid umgewandelt wird. Durch Darstellung und Umsetzung des Triphenyl-α-methyl-allylen-phosphorans mit Diphenylchlorphosphin wird die γ-Substitution bewiesen.Triphenyl-methylen-phosphoran liefert mit Phosphortrichlorid, Phosphoroxychlorid und Phosphorthiochlorid die „Trisylene“ Die phosphinosubstituierten Phosphinalkylene werden durch Umsetzungen mit Alkylhalogeniden und Chlorwasserstoff näher charakterisiert.
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  • 170
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 874-875 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 2 Tab.
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  • 171
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 876-877 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Ill.
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  • 172
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 881-883 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Ill.
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  • 173
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 889-892 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Zinkdicyanimid reagiert mit Methanol unter Bildung von Zink-bis-(imino-bis-carbimidsäuremethylester). Durch Behandeln mit Schwefelwasserstoff läßt sich hieraus der freie Ester gewinnen. Beide Verbindungen liefern mit Carbonsäureanhydriden oder Carbonsäurechloriden substituierte Dialkoxy-s-triazine.
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  • 174
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 884-888 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Hexa-coordinated complexes of nickel(II) bis(methylacetoacetate) with pyridine, β-picoline and β-picoline have been prepared and characterised. Conductance measurements in methanol indicate non-electrolytic nature of the complexes. The complexes are all pale blue in color and are paramagnetic (μeff. = 3.0-3.1 B.M.). Electronic spectra and magnetic moment identify the complexes as octahedral ones. The d-d spectra of the complexes are discussed in the light of the structure of the complexes. The spectrophotometric data for the adducts have been used to calculate the values for the parameters, Δ, B′, β and λ.
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  • 175
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 893-896 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of the hydrolysis of n-amyl bromide and iso-amyl bromide have been studied in alkaline and neutral media at different temperatures in varying ethanol-water mixtures. The substitution and elimination reactions occur simultaneously in alkaline medium, while in neutral medium only substitution reaction occurs. They have been analysed kinetically and given separate rate constants.
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  • 176
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    Journal für Praktische Chemie/Chemiker-Zeitung 311 (1969), S. 897-905 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Durch Alkylierung von 4-Acylamino-1,2,4-triazolen oder durch Acylierung von 1-Alkyl-4-amino-1,2,4-triazoliumsalzen entstehen 1-Alkyl-4-acylamino-1,2,4-triazoliumsalze 3. Diese gehen mit molaren Mengen wäßriger Alkalilauge in mesoionische Verbindungen 7 über, deren Struktur spektroskopisch und chemisch bewiesen wird. Mit überschüssiger wäßriger Lauge lagern sich 1-Alkyl-4-acylamino-1,2,4-triazoliumsalze 3 und ebenso die mesoionischen Verbindungen 7 in 3-Alkyl-4-alkylamino-1,2,4-triazole 14 um, sofern der Acylrest aliphatisch ist. Durch Dehydrierung und Verseifung werden daraus in zwei Fällen die entsprechenden 4-Amino-1,2,4-triazole gewonnen.
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  • 177
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    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Die in Alkylverbindungen aluminiumorganischer Ätherate enthaltenen „Fremdalkylgruppen“ wurden gaschromatographisch nachgewiesen.Versuche zur thermischen Beeinflussung des Fremdalkylgehaltes führten zu keiner Veränderung desselben, ergaben aber, daß eine „direkte“ Ätherspaltung der Phenoläther unter Eliminierung der Alkylreste am Aluminium und Äthersauerstoff ausgeschlossen werden kann. Unter thermischen Bedingungen (150°) treten die Zerfallsgleichgewichte nach Ziegler auf, erkennbar an der Entwicklung von Äthylen. Die dabei gebildeten Dialkylaluminiumhydride spalten Dialkyl-, Arylalkyl- und Diaryläther. Alle Reaktionsprodukte dieser Ätherspaltungen wurden nachgewiesen. Der Entstehungsweg von Aluminiumtrialkyl-Arylalkylätheraten mit „gemischten“ Alkylgruppen am Aluminium ließ sich mit einer analogen Ätherspaltung aufklären, die auf intermediär bei der Herstellung auftretenden Aluminiumalkylhalogeniden beruht. Das dabei gebildete Alkylhalogenid ist ebenso wie das zur Herstellung eingesetzte befähigt, das Aluminium zu alkylieren.Auch aliphatische Äther lassen sich durch Aluminiumalkylhalogenide spalten, Diaryläther dagegen nicht.Diese Spaltungsreaktionen ermöglichen die Gewinnung von hydridfreien (mit Arylalkyl- und Dialkyläther) und halogenfreien (mit Arylalkyläthern) Aluminiumtrialkyl-Ätheraten. Die Kenntnis des Entstehungsweges der „gemischten“ Ätherate gestattete es, den Fremdalkylgehalt weitgehend auszuschalten. Im Gegensatz zu ätherfreien Aluminiumtrialkylen läßt sich der Fremdalkylgehalt destillativ anreichern.Untersuchungen der Einflüsse von Substituenten am Phenoläther auf die Ätherspaltungen durch Hydride und Halogenide geben Hinweise auf den Mechanismus.
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  • 178
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    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 60,0 °C mitgeteilt [1]. Dabei stehen die Lage der azeotropen Punkte des Systems sowie der Verlauf des Isobarenfeldes im Vordergrund des Interesses. Die gewonnenen Befunde ergänzen bereits an anderer Stelle [2,3] bekanntgegebene Untersuchungsergebnisse von Gleichgewichtsmessungen am gleichen System bei niedrigeren Temperaturen, bei denen das System in flüssiger Phase entmischt.
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  • 179
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    The @Anatomical Record 163 (1969), S. 31-38 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Using rat's circumvallate papillae, ATPase, alk. Pase and acid Pase of taste buds were observed after the transection of the glossopharyngeal nerve.The taste buds began to disappear after the nerve was cut and were completely lost after ten days. Following the regeneration of the glossopharyngeal nerve, taste buds reappeared from the bottom of the gutters of circumvallate papillae about 25 days after the operation.ATPase was strongly present on the cell membrane of taste bud cells as far as they existed during degeneration and regeneration. Alk. Pase, which is normally localized on the superficial layers of the epithelium overlying the gutters of circumvallate papilla, gradually diminished as the taste buds degenerated and reappeared as the taste buds regenerated; that is, the activity began to diminish three days after the operation, became feeble after ten days and reappeared after 25 days. It is concluded that taste bud cells secrete alk. Pase in the gutters of circumvallate papillae. Acid Pase activity, usually found in the supranuclear portion of taste bud cells, was intensely reactive during degeneration but did not reappear at the early stage of regeneration of taste bud cells.
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  • 180
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The endosteal and periosteal diameters of the second metacarpal were measured at the midshaft on radiographs of 62 normal girls at 11.0 ± 0.5 years (pre-menarche) and again at 16.0 × 0.5 (post-menarche). There was an average increase in the periosteal diameter of 10% and an average decrease in the endosteal diameter of 16%, both changes significant at p 〈 0.01. Individual variability was greater for the endosteal than the periosteal surface changes (p 〈 0.01).
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  • 181
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Counts of differentiating motor cells over the length of the brachial lateral motor column (LMC) indicate that a large decrease in cell number takes place during the larval period. During the same period an increase in nuclear size of the motor cells occurs with a maximum size attained just following forelimb emergence. Comparison between development of the LMC at the brachial and lumbo-sacral levels indicates a slight lag in brachial LMC development. Cell number remains greater in the brachial LMC than in the lumbo-sacral LMC, but nuclear size is consistently less in the brachial column. Probably no significant change in cell number occurs after metamorphosis, though there is an increase in cell size.
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  • 182
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
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  • 183
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    The @Anatomical Record 163 (1969), S. 389-401 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: In this experiment actinomycin D was used to explore the action of the wound epidermis on underlying tissues during limb regeneration. In axolotl forelimbs the skin was removed from the elbow to the shoulder. Skin from the right limbs was soaked for three hours in actinomycin D (5.0 or 10.0 μg/ml 0.6% NaCl). For controls, skin from left limbs was soaked in 0.6% NaCl for the same period of time. Each piece of skin was orthotopically replanted, and both limbs were amputated through the treated skin, proximal to the elbow. After an initial healing period, the control limbs regenerated normally. Except for a slightly paler color, limbs bearing actinomycin-treated skin were indistinguishable from the controls, both grossly and histologically, during the first week following amputation. While the control limbs formed early blastemas, no grossly visible evidence of regeneration was apparent in the experimental limbs, but histologically some dedifferentiation was occurring. Normally three to four digits were seen in the control regenerates before blastemas appeared on the experimental limbs. By 35-40 days blastemas had appeared on most experimental limbs. These developed very rapidly, and within a short time many of them had attained levels of development close to the controls. Actinomycin D temporarily suppresses formation of the apical epidermal cap and the subsequent aggregation of dedifferentiated cells into a blastema. When the effect wears off, an apical cap forms and the dedifferentiated cells quickly organize into a blastema and begin to differentiate.
    Additional Material: 2 Ill.
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  • 184
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    The @Anatomical Record 163 (1969), S. 373-387 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Pregnant mice were hypophysectomized on day 6 and injected subcutaneously with various hormones from days 6 to 9 to establish the minimal requirements for the maintenance of functional corpora lutea. Luteal activity was assessed by the maintenance of pregnancy, weight of embryonic swellings, mean diameter and morphology of corpora lutea, and vaginal histology.Treatment with 2 mg progesterone maintained pregnancy but not corpora lutea in three of five animals. However, the embryonic swellings were significantly (P 〈 0.0005) smaller than those of pregnant control animals. Pregnancy was maintained in all animals when progesterone was combined with 1 μg of estrone. The weights of embryonic swellings and the degree of vaginal mucification in the combined steroid group were similar to those of intact control animals.Treatment with either ovine prolactin, bovine LH, ovine FSH or estrone failed to maintain corpora lutea or pregnancy. Combined injection of prolactin with LH or estrone did not maintain pregnancy or corpora lutea. On the other hand, treatment with 500 μg of prolactin and 200 μg of FSH maintained pregnancy in 12 of 14 animals. All of the aforementioned parameters of luteal activity were comparable to values in intact, control animals.The data indicate that luteal function in the mouse during the early post-implantation period requires a luteotropic complex rather than a single hormone. Prolactin and FSH constitute the minimal luteotropic complex in the pregnant mouse. The luteotropic activity of FSH was not due to its contamination with LH and the effect of FSH was apparently not mediated through estrogen secretion, since pregnancy was not maintained by prolactin and estrone.
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  • 185
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Representative pieces of labyrinth of near-term chorioallantoic placentas from three species of Dipodomys and one species of Microdipodops were fixed in glutaraldehyde and osmium tetroxide and examined with the electron microscope. The barrier separating the fetal and maternal blood streams in the labyrinth was found to consist of (1) the fetal endothelium and its associated basal lamina (basement membrane), (2) a single layer of trophoblast which is cellular rather than syncytial, and (3) the maternal endothelium and its associated basal lamina. Thus the chorioallantoic placenta appears to be of the endotheliochorial type in these rodents rather than hemochorial or hemoendothelial as previously suggested.
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  • 186
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 163 (1969), S. 555-561 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: A line sampling method was used to determine the relative volumes of various cell types in the mucosa of the body of the rat stomach. The technique was simple to perform, reproducible and independent of many variables inherent in previous cell counting techniques. Weights of the various cell types were calculated from stomach weights, relative mucosal volumes and cell concentrations in the mucosa. In the five animals studied, gastric body mucosa average 40% of the stomach weight and 1.8 gm per kg of rat. Parietal cells averaged 40% of the gastric body mucosa weight and 0.7 gm per kg of rat. There was no significant variation in parietal cell concentration throughout the gastric body mucosa of the rat. Chief cells averaged 18% of the gastric body mucosa and 0.3 gm per kg of rat. Up to three-fold variations in chief cell concentration occurred with highest concentrations near the greater curvature and in proximal areas of the body mucosa. Mucous surface cells, mucous neck cells, and connective tissue made up 22, 9, and 7% of the body mucosa respectively and showed only minor varitions in concentration.
    Additional Material: 8 Ill.
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  • 187
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    The @Anatomical Record 163 (1969), S. 595-601 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: In combination with biochemical determination of cholesterol in testes, cholesterol was studied histochemically in the testicular interstitial cells of dd strain mice from 5 to 63 days.Cholesterol is found in interstitial cells at five days and cholesterol positive interstitial cells increase significantly from 7% at 5 days to 47% at 21 days (17% at 7 days, 21% at 10 days and 31% at 14 days) and thereafter gradually to 58% at 63 days (50% at 28 days, 54% at 35 days, 56% at 42 days, 58% at 49 days and 57% at 56 days).The cholesterol concentration of testes (μg of cholesterol per mg testicular weight) remains at low values before 42 days (1.33 at 5 days, 2.12 at 7 days, 1.89 at 10 days, 2.18 at 14 days, 2.16 at 21 days, 1.63 at 28 days and 2.09 at 35 days) but it increases rapidly at days 42-49 (2.21 at 42 days and 5.16 at 49 days) and then it is almost unchanged (5.47 at 56 days and 5.18 at 63 days).From these results it is suggested that (1) at five days testicular steroid could be elaborated and (2) the capacity of interstitial cells to produce testicular steroid elevates actively from 42 to 49 days.
    Additional Material: 1 Ill.
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  • 188
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 164 (1969), S. 47-65 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Thymic rudiments from mouse embryos varying in gestational from 10-13 days were examined by light and electron microscopy in an effort to learn the origin of thymic lymphocytes. Lymphocytes were recognized and distinguished from mesenchymal cells and thymic epithelial cells by their round shape, larger nucleoli, and high concentration of cytoplasmic ribosomes and dearth of endoplasmic reticulum. No lymphocytes could be found at the earliest stage of development of the third pharyngeal pouch  -  at approximately ten days' gestational age. They first appeared in the mesenchyme surrounding the third pouch at a later stage, (approximately 11 days' gestation), but in most cases did not appear in the thymic epithelium until the parathyroid and thymus began to differentiate at approximately 12 days' gestation. No cells were seen that appeared to be transitional between lymphocytes and epithelial or mesenchymal cells and it was concluded that these observations support the hypothesis that lymphocytes first reach the thymic parenchyma by immigration from the surrounding mesenchyme. Most of the lymphoctyes found in the region of the thymus at these stages of development were large lymphocytes. The origin of these early lymphocytes remains unknown.
    Additional Material: 1 Ill.
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  • 189
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The entry zone of trigeminal sensory root fibers displays a “glial dome” covered by a basal lamina. This zone constitutes the “fibrous cone” of gross descriptions of the root and demarcates a sharp transition from peripheral to central nervous system. The dome consists of closely interwoven astrocyte processes, and appears to be identical to the subpial astrocyte meshwork elsewhere in the central nervous system. In the peripheral portion of the root, axons are surrounded by Schwann cells; those associated with myelin sheaths display distinctive laminar inclusions and pinocytotic vesicles lacking in Schwann cells which surround unmyelinated axons. In the peripheral region, separate and distinct endoneurial and perineurial layers of collagen could not always be identified. In the central part of the root, Schwann cells, fibroblasts, and collagen are absent and from the point of transition, the axons are principally surrounded by astrocytes. Oligodendrocytes are relatively rare in the transitional zone. The axonal transition from central to peripheral, occurs at nodes of Ranvier where the basal lamina of the dome is continuous with the basal lamina of the Schwann cell of the last peripheral internode. Some “islands” of glial tissue are interspersed in the root and ganglion but it was not established if these are completely discontinuous with the central “glial dome.” No ganglion cells have been found in such “islands,” nor in the glial dome.
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  • 190
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: In order to verify the concept that growth hormone and prolactin are contained in two different populations of acidophils, sections of Bouin-fixed rat hypophyses were stained immunochemically. For this purpose the histochemical demonstration of peroxidase was utilized after sequential application to the tissue section of rabbit antiserum to human growth hormone (or antiserum to rat prolactin) followed by application of peroxidase-labeled sheep antiserum to rabbit gamma-globulin. It was found that growth hormone cells and prolactin cells, when revealed immunochemically, corresponded structurally to cell types that could be differentiated with reasonable certainty in sections stained with the Masson trichrome procedure. When delineated immunochemically, growth hormone cells were larger and more densely arranged in the adult male than in the intact female; they exhibited little change in the female after ovariectomy. In contrast, prolactin cells were large and frequent in the female hypophysis but were small and less frequent in the male and in the female after ovariectomy. By double-staining, growth hormone and prolactin cells were differentiated in the same section. It was concluded that (a) growth hormone and prolactin are contained in, and presumably secreted by, two different populations of acidophils; and (b) the Masson procedure permits a reasonably accurate differentiation of the two cell types.
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  • 191
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    The @Anatomical Record 164 (1969), S. 173-184 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Certain members of the extinct reptilian group from which mammals evolved possessed both a dens and an atlas body. Available paleontologic evidence supports the conclusion that the dens evolved as an addition to the atlas body. There-fore, the dens is not homologous with the atlas body as is generally claimed on the basis of supposed developmental evidence. The atlas body is large in the most primitive of living mammals, the monotremes, which also possess a dens of typical mammalian proportions. In metatherian and most eutherian mammals, both a dens and an atlas body remnant of variable size are present. The development of the dens in the Virginia opossum, Didelphis marsupialis, confirms the fact that the dens arises from, but does not replace, the atlas body anlage. The dens evolved as a functional replacement of the atlanto-axial articular processes which were lost when the mammalian atlanto-axial joint became specialized for rotational movement.
    Additional Material: 5 Ill.
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  • 192
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Cells of the vaginal epithelium of ovariectomized mice undergo differentiation in response to estrogen or progesterone injection. Estrogen causes an increase in number of cytoplasmic filaments in the basal and newly formed spinous layer and mucification of surface cells already present. The cells derived from the basal layer under estrogen influence later form a keratinized epithelium. Progesterone causes heightening and mucification of surface cells and invasion of leucocytes into the epithelium without mucification or keratinization of other cells. When estrogen is followed two days later by progesterone, spinous and more superficial cells are lost and replaced my mucous cells derived from the basal layer. Although the fine structure of basal and spinous cell cytoplasm looks identical, the spinous cells do not form mucous cells under progesterone influence. The reverse sequence of progesterone followed by estrogen produces a low epithelium which is then replaced by a keratinized epithelium. The surface mucous cells present during progesterone influence do not keratinize, however. Thus, fine structural features of basal cells typical for the influence of a given hormone do not limit or characterize the potential of daughter cells derived from that layer. Conversely, when hormones are used in sequence, cells which leave the basal layer under the influence of one hormone do not acquire the fine structural features characteristically produced by the second hormone used, even though basal cells are readily altered.
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  • 193
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 164 (1969), S. 259-265 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Histological preparations from skin of the Australian black snake, Pseudechis Porthyriacus have revealed myelinated nerve fibers terminating in several structures. The commonest of these, the simple “End Button,” was seen in the epidermis from all regions of the body. An end organ, the “touch corpuscle” occurred in the epidermis of the upper and lower lip, while in the dermis of the upper and lower jaw an encapsulated structure, the “club corpuscle” was frequently encountered. These more complex structures could not be revealed in skin of the trunk where only “end buttons” were seen.
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  • 194
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    The @Anatomical Record 164 (1969), S. 283-289 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: A study of the crura of the diaphragm and their innervation from the phrenic nerve was made in 22 fresh specimens and four embalmed specimens. The arrangement of the musculature was found to be essentially the same as that described by Low in 1907. The portions of the crural musculature passing to the right and left of the esophagus did not decussate anterior to the esophagus as these fibers insert into the central tendon. The right and left phrenic nerves divided into three to five divisions at the pericardiodiaphragmatic angle. Most commonly, these divisions are: anterior, posterior and lateral. If there are more than three divisions involved, there is usually a medial division present and/or a subdivision of one of the other divisions. It is the posterior division or its posteromedial branch which contributes to the innervation of the crura. None of the other divisions contributes to the innervation of the crura. Secondary branches of either the posterior division or the posteromedial branch do not cross to the contralateral side.
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  • 195
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Ligatures were placed unilaterally on the ductus deferens (experiment 1), on the ductus deferens and the middle of the corpus epididymidis (experiment 2) and on the ductus deferens, corpus epididymidis and ductuli efferentes (experiment 3) in 39 rabbits. The untreated contralateral side served as a control. Vasectomy alone appeared to have no effect upon the testes, or upon spermatozoa accumulated during a period of 12 weeks proximal to the ligature. In experiment 2 severe disruption of spermatogenesis occurred. Diameter of the seminiferous tubules decreased, testes atrophied, and the stages of the seminiferous epithelium were abnormal and often not classifiable. Some regeneration was observed after 12 weeks.In experiment 3 there was only a moderate and more transient disturbance of spermatogenesis. This occurred in spite of an accumulation of fluid in the testis due to the ligature on the ductuli efferentes, which prevented testicular effluent from reaching the caput epididymidis. These results suggest that when testicular effluent is allowed to reach the caput, but nonresorbed residues are prevented from further transport (experiment 2), a feedback to the testis occurs which is more harmful than that produced by preventing tubular contents from leaving the testes.
    Additional Material: 3 Tab.
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  • 196
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    The @Anatomical Record 165 (1969), S. 127-139 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: In the course of ultrastructural studies on the cerebellar cortex of young rats a cilium was found in some Purkinje cells. The shaft, which is 1800 to 2000 ÅR thick, has an internal portion inside the cell body and an external one projecting into the neuropile. The basal body is consistently located near the Golgi apparatus. Rootlets with periodic cross-striations (interperiod distance of 525 ÅR) are attached to the basal body. The size and characteristics of the Purkinje cell cilium and its constituent parts compare with similar structures in the cilia of other cell types of the cerebellar cortex. Whether all or only some of the Purkinje cells have a cilium has not yet been determined. Possible functional roles of these organoids are considered.
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  • 197
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    The @Anatomical Record 165 (1969), S. 185-195 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: In amphibian melanophores, premelanosomes appear to be formed in fenestrated cisternae of the Golgi complex. The premelanosomes may develop within the cisternae or vesicles containing melanoprotein may bud from the cisternae to form premelanosomes. Some micrographs also demonstrate a close association between microtubules and either premelanosomes or melanosomes. The microtubules themselves may originate from electron dense particles in the centrosphere region of the cell.
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  • 198
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The appearance of the carbohydrate-rich surface coat covering the the intestinal epithelium of the cat varies with different methods of fixation for electron microscopy. A fibrillar surface coat covers the external surfaces of the microvilli after fixation in glutaraldehyde and postfixation in phosphate-buffered OsO4; its density is enhanced by heavy metal staining. In tissue fixed in glutaraldehyde alone or followed by dehydration in acetone and postfixation in OsO4 in carbon tetrachloride, a structureless zone less dense than Epon occurs where the surface coat is usually visualized; heavy metal staining does not impart density to the zone. The absence of structure and low density of the zone are not due to extraction of the surface coat by dehydrating agents or by carbon tetrachloride. The data suggest that osmium binds to the surface coat from phosphate buffer, but not from carbon tetrachloride. Also OsO4 in phosphate buffer, but not OsO4 in carbon tetrachloride, facilitates heavy metal staining of the surface coat. Acidic carbohydrates appear to be important for the differential binding of osmium observed in this study. The need for caution in interpreting low density areas of electron micrographs as extracted structures and high density areas as “osmiophilic” structures is discussed.
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  • 199
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The development of the pineal organ in the newt Taricha torosa has been studied utilizing cell counts and radioautography following single injections of tritiated thymidine. Embryos injected two weeks before hatching (series I) demonstrated a grain distribution pattern in the pineal organ and its underlying proliferation zone characteristic of continuous availability of isotope. Larvae injected at hatching (series II) or two weeks after hatching (series III) displayed the expected pulse label pattern for these same regions. With the possible exception of some mitosis insituin the youngest organs, pineal cells originate from a mitotically active cell population which comprises the pineal proliferation zone. After cell division some daughter cells migrate into the pineal organ, moving into the posterior part of the organ during the prehatching period, while from hatching onward the predominant migration is into the anterior part of the organ. Both the pineal photoreceptors and supportive cells arise in this manner with labeled cells of both types found in all three series, but in decreasing numbers from the youngest to the oldest series.Cell counts disclose an approximate ten-fold increase in the number of cells within the pineal organ from embryonic to adult stages, but the rate of cell addition slows with increasing age. Both photoreceptors and supportive cells show this increase in number with the photoreceptor population being maintained at a constant 14%-18% of the total pineal population over this entire five-year period.
    Additional Material: 10 Ill.
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  • 200
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 165 (1969), S. 329-341 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Myoid cells of the thymus of hibernating frogs were examined by electron microscopy. This cell type is represented by immature, fully-developed and degenerating cell forms. The immature forms are mainly located at the surface, whereas the developed ones are found in the inside of the thymus. A peculiar type of immature cell containing no thick filaments, but possessing a rich sarcoplasmic reticulum among the thin filaments is described. The developed myoid cells have a myofibrillar apparatus showing regular cross-striations. The myofibrils are arranged in concentric layers around the nucleus. The proposed role and origin of myoid cells and their probable connection with myasthenia gravis are discussed.
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