US 5,317,099 A · Process for the preparation of cephem derivatives

Abstract

A process for preparing B-lactam derivatives of the formula (I): ##STR1## wherein R.sup.1 represents hydrogen or a metal salt; and R.sup.2 represents hydrogen, acetoxy methyl, (2,5-dihydro-2-methyl-6-hydroxy-5-oxo-as-triazin-3-yl)thiomethyl or (1-methyl-1-H-tetrazol-5-yl)thiomethyl is disclosed. This process comprises the steps of (a) reacting triphenylphosphine and hexachloroethane or carbon tetrachloride with 2-(2-aminothiazol-4-yl)-2-syn-methoxyimino acetic acid in an organic solvent to give the corresponding acyloxyphosphonium chloride derivative of the formula: ##STR2## (b) acylating a previously silylated derivative of 7-ACA with this acyloxyphosphonium chloride derivative without its isolation.

Claims6

Dependent claims

A process for preparing a compound of the formula:

##STR10## wherein R.sup.1 represents hydrogen or a metal salt;
and R.sup.2 represents hydrogen, acetoxymethyl, (1-methyl-1H-tetrazol-5-yl)thiomethyl or (2,5-dihydro-2-methyl-6-hydroxy-5-oxo-as-triazin-3-yl)thiomethyl,
which process comprises the steps of:
(a) reacting a mixture of triphenylphosphine (Ph.sub.3 P) and hexachloroethane (C.sub.2 Cl.sub.6) or carbon tetrachloride (CCl.sub.4) with an organic acid of the formula:
##STR11## in an organic solvent to give an acyloxyphosphonium chloride derivative of the formula:
##STR12## (b) acylating a silylated derivative of 7-ACA of the formula (V):
##STR13## wherein R.sup.2 is the same as defined above, wherein the acyloxyphosphonium chloride derivative is not isolated.

4 more elements

Dependencies are inferred from the claim text.

Process for the preparation of cephem derivatives

Life of this patent

Process for the preparation of cephem derivatives

Life of this patent

Abstract

Claims6