The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 18, 1997
Filed:
Dec. 27, 1993
Lupin Laboratories, Ltd., Bombay, IN;
Abstract
An improved method for the preparation of 2-chloro sulfinyl azetidin-4-one of the formula: ##STR1## wherein R is: hydrogen; C.sub.1 -C.sub.3 alkyl; halomethyl; cyanomethyl; phenyl; substituted phenyl; phenoxy, benzyloxy- or substituted benzyl; a group of the formula R.sub.2 --O--wherein R.sub.2 is t-butyl, 2,2,2-trichloroethyl, benzyl or substituted benzyl; a group of the formula R.sub.3 --(O).sub.n --CH.sub.2 wherein R.sub.3 is phenyl or substituted phenyl. The 2-chlorosulfinylazetidin-4-one is prepared by reacting a penicillin sulfoxide ester of the general formula ##STR2## wherein R and R.sub.1 have the meanings defined above with an N-chloro halogenating agent in an inert organic solvent. The reaction is carried out in the presence of an acid scavenging amount of a phosphate or hydrogen phosphate of an alkali metal, alkaline earth metal, ammonium, quaternary ammonium or mixtures thereof. These compounds find application as intermediates in the production of cefaclor which are powerful anti-bacterial compounds.