| abstract |
NEW MATERIAL:A compound expressed by formula I [R 1 is aryl, CN, amidino, carbamoyl, 1-alkoxy-1-iminomethyl, amino-substituted thiazolyl, etc.; R 2 is organic group; R 3 is (protected) carboxy or formula II (R 3 is -COO - or carboxyl; R 4 is H, pyridiniomethyl or heterocyclic thiomethyl which may have a substituent group)] or salt thereof. n EXAMPLE: 7-[ 2-( 2-Aminothiazol-4-yl )-2-methylthioiminoacetamido ]-3-cephem-4- carboxylic acid. n USE: The compound in which R 5 is expressed by formula II (cephalosporanic acid derivative) is capable of preventing growth of a wide range of pathogenic germs including Gram-positive and Gram-negative bacteria and useful as an antimicrobial agent. n PREPARATION: For example, a compound expressed by formula III is subjected to simultaneous elimination reaction of a carboxy-protecting group R 10 and amino-protecting group R 6 and then reacted with a compound expressed by formula IV to afford the compound expressed by formula I (R 5 is carboxy), which is then reacted with a compound expressed by formula V to provide the compound in which R 5 is expressed by formula II. n COPYRIGHT: (C)1988,JPO&Japio |