Optically active bicyclic imino-alpha-carboxylic esters

US4822894A · kind A · utility

Assignee

• Hoechst GmbH · DE

Inventors

• Rolf Geiger · Frankfurt am Main, DE
• Volker Teetz · Hofheim, DE
• Dietrich Langner · Frankfurt am Main, DE
• Hansjorg Urbach · Kronberg, DE
• Rainer Henning · Tokyo, JP

Key dates

• Filing date: Mar 9, 1987
• Grant date: Apr 18, 1989
• Expiry date: Mar 9, 2007

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07K5/06078
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The invention relates to a process for resolving racemic mixtures of bicyclic imino-.alpha.-carboxylic esters into the components by crystallization of diastereomeric salts, which comprises preparing the salts of the racemic esters with optically active N-acylated R- or S-amino carboxylic acids which contain a phenyl nucleus, recrystallizing them from an organic solvent, decomposing the precipitated, optically homogeneous diastereomeric salts in a manner known per se, and isolating the enantiomers and, where appropriate, converting the latter into the free acids by hydrolysis in a manner known per se. The invention also relates to optically pure compounds of the formula ##STR1## and to diastereomeric salts of these compounds, in which two of the radicals A, B.sup.1, B.sup.2 and C form a carbon chain and the others denote hydrogen, and R is an esterifying group.