| abstract |
An oral antibacterial, 7beta-[(Z)-2-(2-aminothiazol-4-yl)-2-alkenoylamino]-3-cephem-4-carboxylic acid pharmaceutically acceptable ester represented by the following formula: <IMAGE> (wherein R is amino or protected amino, R1 is straight, branched, or cyclic alkyl optionally substituted by alkoxy, R2 is hydrogen or a 3-substitutent of cephalosporins, R3 is a pharmaceutically acceptable ester group, and X is sulfur or sulfinyl). |