| 摘要 |
<p>Compounds of formula I wherein R1 is hydrogen, lower alkyl, cycloalkyl or acetyl; x is CH or N; n is 0, 1 or 2; m is 0 or 1; R2 is hydrogen, lower alkyl, omega -hydroxy alkyl, benzyl or lower alkyl-heterocyclyl, the benzyl and the heterocyclyl group being unsubstituted or substituted with at least one of the groups amino, cyano, carboxy, halogen, hydroxy, lower alkyl, lower alkoxy or -CONR2, where R is hydrogen or lower alkyl; or R2 is -CH2CONR4R5; wherein R4, R5 are each independently hydrogen, omega -hydroxy-alkyl, phenyl, benzyl, naphthyl or heterocyclyl, the phenyl, benzyl, naphthyl or heterocyclyl groups being unsubstituted or substituted with at least one of the groups optionally protected hydroxy, halogen, optionally substituted lower alkyl, optionally substituted lower alkoxy, omega -hydroxyalkyl or cyano; or R4 and R5 form together a group of formula with the proviso that when pyridinium ring A is pyridinium-4-yl, m is 1; as well as readily hydrolysable esters thereof, pharmaceutically acceptable salts of said compounds and hydrates of the compounds of formula I and of their esters and salts. These compounds are useful as parenteral antibiotics.</p> |
