NEW MATERIAL:A cephalosporin derivative and its salt of formula I [R1 is H, amino; R2WR4 are H, OH, oxo, mercapto, etc.; R5 is H, lower alkoxy; R6 is acetoxy, -S-R7 (R7 is 5,6 membered heterocyclic ring which may be substituted by halogen mercapto, etc.); A is mono- or bi-cyclic hetero-ring containing 1-2 N, O or S atoms].
EXAMPLE: DL-7- [ 2- ( 4-hydroxy-6-methylnicotinamide ) -2- ( thiazol-4-yl ) acetamide] cephalo-sporanic acid.
USE: Antibacterial agent effective to gram-positive and gram-negative bacteria, expecially to gram-negative bacteria.
PROCESS: The compound I is prepared by reacting 1 mole of a compound II with ≥1 mole of a compound III in an organic solvent such as methanol, pref. in the presence of a base (e.g. triethylamine, etc.) at or below room temperature.
ISAKA ICHIROU
MURAKAMI YUKIYASU
