| 摘要 |
Compounds having the formula: <CHEM> wherein R1 is selected from the group consisting of hydrogen, alkyl(C1-C6), polyfluorinated alkyl(C1-C6), phenyl, multisubstituted phenyl wherein the substituents are selected from alkyl(C1-C6), alkoxy(C1-C3), chloro, fluoro and trifluoromethyl, naphthyl, thienyl, phenylthio, tetrahydropyranyl, benzyl, and -COOC2H5; R2 is selected from the group consisting of hydrogen, diphenylmethyl, alpha -acyloxyalkyl, t-butyl, benzyl, 4-nitrobenzyl and 4-methoxybenzyl and pharmaceutically acceptable salts (sodium and potassium); and R3 is selected from the group consisting of hydrogen, <CHEM> <CHEM> , where R5 is selected from the group consisting of phenyl, substituted phenyl, 2-thienyl, 2-furyl, trifluoromethylthiomethyl, 4-(2-aminothiazoyl), 5-(2-aminothiazoyl) and cyanomethylthiomethyl, and R6 is selected from the group consisting of hydrogen, 4-alkyl(or aryl)-2,3-dioxopiperazine-1-carbonyl, ureido and carboxyamido, phenylacetyl, heterocyclic acetyl, <CHEM> where X is selected from the group consisting of OH, SO3H, COOH and tetrazolyl; and R4 is selected from the group consisting of hydrogen, -O-alkyl, -S-alkyl and formamido, its esters and salts, are useful as anti-bacterial agents. |
