7-α-methoxycephalosporin derivatives, and antibacterial drugs onctaining the same

Claim 1

A 7α-methoxycephalosporin derivative represented by the formula: ##STR9## wherein R 1 represents nitrogen-containing heterocyclic-thio, the nitrogen-containing heterocyclic moiety of which is selected from the group consisting of pyrrolyl, pyridyl and its N-oxide, imidazolyl, pyrazolyl, pyrimidinyl, pyridazinyl, 1H-1,2,4-triazolyl, 4H-1,2,4-triazolyl, 1H-1,2,3-triazolyl, 2H-1,2,3-triazolyl, 1H-tetrazolyl, 2H-tetrazolyl, thiazolyl, 1,2,3-thiadiazolyl, 1,2,4-thiadiazolyl, 1,3,4-thiadiazolyl, oxazolyl, 1,3,4-oxadiazolyl, 1,2,5-oxadiazolyl, morpholino, benzothiazolyl and benzoxazolyl, said heterocyclic moieties being unsubstituted or substituted by methyl, ethyl, propyl, isopropyl, dimethylaminoethyl, dimethylaminomethyl, diethylaminoethyl, methoxycarbonylmethyl, ethoxycarbonylmethyl, carboxymethyl or carboxyethyl; R 2 represents hydrogen or hydroxy; and R 3 , R 4 , R 5 and R 6 each represents a group selected from the class consisting of hydrogen, hydroxy, lower alkanoyloxy, methoxy, ethoxy, propoxy, methyl, ethyl, n-propyl, i-propyl, n-butyl, t-butyl, halogen, benzyloxy, phenethyloxy, nitro, methoxycarbonyloxy, ethoxycarbonyloxy and 2,2,2-trichloroethoxycarbonyloxy, or a pharmaceutically acceptable salt thereof.