Sidney Teitel

Pharmacologic activity of stereoisomers of 1-substituted 6,7-dihydroxy-1,2,3,4-tetrahydroisoquinolines: Inhibition of 3H-dopamine accumulation by rat brain slices and lipolytic activity with isolated mouse fat cells

A number of 6,7-dihydroxy-1,2,3,4-tetrahydroisoquinolines related to dopamine were studied for their inhibitory effects on accumulation of 3H-dopamine by rat brain slices and for lipolytic activity with isolated mouse fat cells. The unsubstituted 6,7-dihydroxytetrahydroisoquinoline (ED50 7.4 × 10−5 M) and S-(−)-salsolinol (ED50 7.5 × 10−5 M) were the most effective inhibitors of 3H-dopamine accumulation. R-(+)-Salsolinol, R-(+)-tetrahydropapaveroline and S-(−)-tetrahydropapaveroline were less effective inhibitors (ED50 17–22 × 10−5 M). S-(−)-Tetrahydropapaveroline was a very effective lipolytic agent with isolated fat cells (ED50 2.0 × 10−7 M), whereas the R-(+)-form was inactive up to 10−5 M. These data illustrate the importance of the absolute configuration at the 1-position of the tetrahydroisoquinoline ring for regulating some of the pharmacologic actions of these 6,7-dihydroxylated derivatives.

Absolute configuration of cryptostylines I, II, and III by x-ray analysis and aromatic chirality method

Abstract The S-configuration of the alkaloids cryptostylines I, II, and III was assigned on the basis of a single crystal X-ray analysis of unnatural cryptostyline II hydrobromide (5.HBr: orthorhombic, P212121 a = 10·162, b = 12·352, c = 16·456 A) and confirmed by application of the aromatic chirality method. Further evidence for the configurational assignment was provided by the CD spectra of the monophenolic derivatives of unnatural cryptostyline II (14).

Eine neue Synthese von Nornarcein

N-benzylnornarceine-ethyl ester hydrochloride (3a) and N-benzylnornarceinehydrochloride (4a), both obtained byHofmann degradation of N-benzylnarcotinium bromide (2), are debenzylated catalytically to nornarceine-ethylester-HCl-salt (5) and nornarceine (6).AbstractDie HCl-Salze von N-Benzylnornarcein-äthylester (3a) und N-Benzylnornarcein (4a), erhältlich durchHofmann-Abbau aus N-Benzylnarcotiniumbromid (2), werden katalytisch zu Nornarcein-äthylester-Hydrochlorid (5) und Nornarcein (6) entbenzyliert.

Synthesis in the emetine series—XIV : A new synthesis of 2,3,11-trisubstituted berbines

Abstract A new synthesis of 2,3,11-trisubstituted berbines is described. By this method the dimethoxysubstituted benzoquinolizidine keto ester I is annealted with a four carbon unit, cyclized and aromatized in the presence of an alcohol to give the 2,3-dimethoxy-11-alkoxy-substituted berbines VIII, IX and X. The stereochemistry of the intermediate compounds has been elucidated by physical-chemical methods.

(±)-Homoberbines, a new class of heterocyclic compounds

Die sekundären Tetrahydroisochinoline Ia, b, c wurden mit Hilfe einer modifizierten Pictet-Spengler-Kondensation in die (±)-Homoberbine IIIa, b, c übergeführt. Diese Homoberbine stellen eine neue Klasse potentieller Alkaloide dar.

8-Methxlcorxpallihe and its O-Metbzlzzher: A Facile Sxhthesis of 8-Methxl Substituted-6, 7- Dimethoxy Tetrahsdroisoquxnolines

Abstract The optically active B-Methy1 substituted tetrahydroisoquinoline (−)− 1 is a major reaction product in the cleavage of the bisbenzylisoquinoline alkaloid repanduline with potassium in liquid ammonia.1 A synthesis of (±) − 1 by a rather lengthy procedure has been reported.2 In this connection we now wish to report a simple and efficient method of introducing an 8-methyl substituent into a 7-hydroxy-6- methoxy tetrahydroisoquinoline. This approach, which has probably wider applications, is exemplified by the synthesia of 8-methylcorypalline 4 and its O-methylether 5 and involves the thiomethylation reaction of poppeladorf and Holt3 followed by reductive desulfurization of the phenyl thiomethyl intermediate.