Molecular variations vinylogues

Molecular Variations in Homologous Series Vinylogues and Benzologues... 

MOLECULAR VARIATIONS IN HOMOLOGOUS SERIES VINYLOGUES AND BENZOLOGUES... 

These vinylogues have the advantage of being more stable towards in vivo metabolism. In addition they allow molecular variations with ortho, meta and para positional isomers. Thus, for cyclovinylogues of procainamide, the highest local anaesthetic activity was found with the meta derivative, which also showed the best dissociation... 

Fig. 18.10 Molecular variations applied to diazepam (1). Compounds (2) and (3) are positional isomers optical isomerism is introduced in (4). Compound (5) is a vinylogue (vinylogy is also used to render amidic the carbonyl of (14). Compounds (6) and (7) are isosteres. Compounds (8) to (15) result from various ring modifications enlargement (8), contraction (9), introduction of additional rings (10 and 11), benzo splitting (12), use of spiro systems (13 and 14), ring opening (15). Compound (16) is a symmetrical twin drug and compound (17) underlines that many substituent variations can be used. The presented structures do not strictly correspond to existing molecules.

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