Process for preparing cephalosporin compounds

Abstract From the Canadian patent

A process for preparing compounds of the formula I: (I), wherein X is sulphur, oxygen, methylene or sulphinyl (R or S configuration), R3 is hydrogen or methoxy R4 is an optionally, substituted (1-4C)alkyl group Y is hydrogen or a carboxyl, protecting group and Q is an optionally protected amino group or an acylamino group, which comprises reacting a compound of formula (II), (II), with a compound of formula (III) (III), wherein R4 is as defined above and W and Z represent hydrogen atoms or a group or groups removable to yield the compound of formula (I). The compounds of the formula I are useful intermediates in the preparation of cephalosporin antibiotics.