Cephem compounds and a production method therefor.

摘要

The invention relates to cephem compounds or salts thereof of the formula: [in the formula, R<1> denotes hydrogen or an amino protective group, R<2> denotes an unsubstituted or substituted alkyl group, X denotes an O-bonded group or S-bonded group, and M<1> denotes hydrogen, carboxyl protective group or a cation and, as COOM<1>, a carboxylate ion, and R<3> denotes a group represented by the formula: (in the formulae, Y<1> and Y<2> are identical or different and denote hydrogen, alkyl groups, halogen groups, hydroxyl groups or oxo groups, R denotes an alkyl group, and the bonding partner of the -X- group is positioned in the 1-position, 3-position or 4-position of the pyridine ring (but excluding the 1-position in the case of the pyridinium ring and the pyridine N-oxide ring)) (but excluding groups represented by the formula (II b) when X is an S-bonded group,], methods of making such compounds and antimicrobial agents incorporating them.