| abstract |
Carboxylic acid compounds of the formula wherein the index n is an integer from 1 to 4, the index m 0 or 1, X is oxygen, sulfur or the group -NH-, W is a group -CO-, -CO-NHS0 2 - or -S0 2 NH-CO -, or XW together a group -CO- or -CO-NHS0 2 -, A optionally substituted phenylene, thienylene or furylene, Y hydrogen, hydroxyl, formyloxy, amino or optionally sulfo and Z hydrogen, or Y and Z together an oxo group or a group = NOR °, in which R ° represents hydrogen or optionally substituted lower alkyl. and in which the aminocarboxylic acid group HOOC-CH (NH 2 ) - and optionally in the grouping -A- (Y) (Z) - further functional groups present are present in protected form. and their reactive derivatives suitable for acylation. and processes for their manufacturen n n The compounds are suitable for the preparation of new cephalosporin derivatives in which the 7β-amino group is acylated by the acyl groups of these carboxylic acid derivatives. |