Abstract: The present invention relates to a process for preparing a beta-keto ester compound of formula (1), which is an intermediate for the synthesis of quinolone antibiotics. Particularly, the present invention is characterized by the reaction of an organo nitrile compound with a salt of mono-alkyl malonate in the presence of metal salt, and so the reaction is easy to control due to its endothermic nature, and is devoid of lachrymatory reagents with excellent reproducibility. Subsequent in situ hydrolysis in the presence of aqueous acid solution provided the compound of formula (1).
Type:
Grant
Filed:
September 15, 2006
Date of Patent:
January 5, 2010
Assignee:
LG Life Sciences Ltd.
Inventors:
Hyun Ik Shin, Bo Seung Choi, Jae Hoon Lee
Abstract: This invention relates to certain steroidal glycosides useful as hypocholesterolemic agents and antiatherosclerosis agents and certain protected intermediates useful in the preparation of said steroidal glycosides.
Abstract: A process for the synthesis of peracyl-1-O-steroidal-.beta.-cellobiosides that provides excellent .beta.-anomeric selectivity without the use of a metal salt promoter. The process comprises reacting heptaacyl-.beta.-D-cellobiosyl-1-fluoride and a trisubstituted silyl-3-O-steroid, wherein the steroid is tigogenin, hecogenin, 11-ketotigogenin or diosgenin in the absence of a metal salt under suitable conditions.
Type:
Grant
Filed:
December 20, 1994
Date of Patent:
October 8, 1996
Assignee:
Pfizer Inc.
Inventors:
Kathleen D. Goggin, John F. Lambert, Stanley W. Walinsky