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:
Oct. 15, 1985
Filed:
Dec. 02, 1983
ICI Pharma, Enghien-les-Bains, FR;
Imperial Chemical Industries PLC, London, GB;
Abstract
A process for the manufacture of a cephalosporin derivative of the formula I ##STR1## in which X is sulphur, oxygen or sulphinyl; R.sup.1 is any one of the C-3 substituents from antibacterially-active cephalosporins known in the art; R.sup.2 is hydrogen or 1-6C alkyl; R.sup.3 is hydrogen or 1-6C alkyl; and the pharmaceutically-acceptable acid-addition and base-addition salts thereof, characterized by cyclization of a compound of the formula II: ##STR2## or a derivative thereof in which the carbonyl group is masked, or an acid-addition salt thereof, in which R.sup.4 and R.sup.5 individually have one of the values for R.sup.2 and R.sup.3, R.sup.6 is a nitrogen-protecting group and R.sup.7 is hydrogen or any one of the cephalosporin 3-carboxylic acid protecting groups known in the art; whereafter when the product from the cyclization retains the protecting group R.sup.7 (when R.sup.7 is other than hydrogen) the protecting group R.sup.7 is replaced by hydrogen by conventional means; and whereafter when the compound of the formula I is obtained in the form of the free base or salt, and a pharmaceutically-acceptable salt or free base respectively is required, any necessary conversion between free base and salt is carried out by conventional means.