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:
Dec. 15, 1987
Filed:
Jan. 24, 1986
Marco Alpegiani, Milan, IT;
Angelo Bedeschi, Milan, IT;
Maurizio Foglio, Milan, IT;
Giovanni Franceschi, Milan, IT;
Ettore Perrone, Milan, IT;
Farmitalia Carlo Erba S.p.A., Milan, IT;
Abstract
A new process is described for the preparation of (5R)-penem derivatives of the general formula I: ##STR1## wherein R.sub.1 represents a hydrogen atom or an organic group; R.sub.2 represents a hydrogen atom or a carboxy protecting group and Y represents a hydrogen or halogen atom or an organic group. A 2-thiacephem derivative of the general formula II: ##STR2## wherein R.sub.1, R.sub.2 and Y have the meanings/given above is oxidized by means of organic peracids to the corresponding sulphone of the general formula III: ##STR3## which is subsequently submitted to a desulphurative ring contraction by extrusion of SO.sub.2 to give exclusively the desired (5R)-penem derivatives of the general formula I.