Alan R Feldman

US Patent:

50268732, Jun 25, 1991

Filed:

Nov 6, 1989

Appl. No.:

7/432028

Inventors:

Neal G. Anderson - Somerset NJ
David A. Lust - Roosevelt NJ
Barbara J. Bennett - North Brunswick NJ
Alan F. Feldman - Philadelphia PA
Robert E. Polomski - Franklin Park NJ

Assignee:

E. R. Squibb & Sons, Inc. - Princeton NJ

International Classification:

C07D20708

US Classification:

548533

Abstract:

A process is disclosed for direct isolation of captopril from a substrate of the formula ##STR1## wherein R is lower alkyl or lower alkoxy. In this process, the substrate is first treated with an aqueous alkali metal hydroxide capable of forming a water-soluble salt of the substrate, wherein the alkali metal hydroxide has a concentration of 4M or greater. The substrate is then neutralized, preferably with a mineral acid. By this process, captopril may be directly crystallized from an aqueous solution, avoiding the prior art use of organic solvents and zinc treatment to reduce levels of sulfide and disulfide impurities, respectively. In an alternative embodiment, neutralization is carried out by use of a hydrogen-supplying ion exchange resin.

Address:

3341 Perimeter Dr, Greenacres, FL 33467

VIN:

2FAFP74V97X127044

Make:

FORD

Model:

CROWN VICTORIA

Year:

2007