Original scientific paper

Isomerisation of N-Acyl Benzylpenilloic Acid in Acetic Anhydride and Formation of 7, 7-Dimethyl-6-thia-3,8-diazahicyclo(3,2,1)octan-2-one

J. J. Herak ; Research Institute PLIVA, Zagreb, Croatia, Yugoslavia
M. Kovačević ; Research Institute PLIVA, Zagreb, Croatia, Yugoslavia
I. Lukić ; Research Institute PLIVA, Zagreb, Croatia, Yugoslavia
B. Gašpert ; Research Institute PLIVA, Zagreb, Croatia, Yugoslavia

Abstract

The heating of N-acyl benzylpenilloic acids {II) in a cetic
anhydride gave an equilibrium mixture of C-4 epimers, due to the
epimerisation at C-4 position. Cyclisation of the 2-amidomethyl and
4-carboxylic group of IIb or IIc into a 2-ketopiperazine ring gave
1S,5S or 1R,5R enantiomer of III. Alkaline hydrolysis of III gave
IV and II. When N-formyl group was present, IV and II upon acid
hydrolysis yielded V and I. The C-4 epimers (lb or le) can be
prepared from trans C-2, C-4 substituted C-4 epimers (Id or Ia)
via II and III.

Keywords

Hrčak ID:

195894

URI

https://hrcak.srce.hr/195894

Publication date:

20.11.1979.

Visits: 820 *