[ [4-[4-Phenyl-1-piperazinyl)phenoxymethyl]-1-3-dioxolan-2-yl]-m
[(Thioalkyl)thioacetyl)]cephalosporin derivatives
[3-(Pyridinium)-7-(naphthyiridinyl carbonylamino)acetamido]cepha
[Amino sulfonyl-2-oxo-nicotinyl]derivatives of cephalosporin
[[[(2,4-Dioxo-1-imidazolidinyl)amino]carbonyl]amino]-acetylcepha
[[[(2,4-Dioxo-1-imidazolidinyl)amino]carbonyl]amino]-acetylcepha
[[[Imidazolidinyl amino]carbonyl]amino]acetyl cephalosporin deri