| abstract |
The present invention provides certain novel cephalosporin derivatives represented by following formula(I), which are especially useful as intermediates for the preparation of cephalosporin compounds possessed with potent and broad antibacterial activities. <CHEM> wherein: R<1> is a C1-4alkyl, C3-4 alkenyl, C3-4 cycloalkyl, amino optionally substititued with a C1-4 alkyl radical, or phenyl group optionally subsitututed on its 2-, 4-and/or 6-position with a halogen, C1-4 alkyl, C1-3 alkoxy or hydroxy radical; R<2> is hydrogen or a C1-4 alkyl group; and n is either 0 or 1. The invention also relates to processes for preparing these intermediates and their pharmacologically active cephalosporin antibiotics. |