New Cephem Compounds.

摘要

A compound of the formula : wherein R<1> is amino or protected amino, R<2> is lower alkyl substituted with 1 to 6 halogen, R<3> is hydroxy(lower)alkyl, protected hydroxy(lower)alkyl or halo(lower)alkyl and R<4> is hydrogen, or R<3> and R<4> are linked together to form lower alkylene, and R<5> is hydrogen or an amino protective group, and a pharmaceutically acceptable salt thereof, processes for their preparation and pharmaceutical compositions comprising them. The invention also relates to intermediate products of the formula and processes for their preparation. e