| abstract |
A process for preparing new cephem compounds of the formula; **(formula)** where R(sup, 1) is amino or protected amino, R(sup, 2) is lower alkyl, R(sup, 3) is hydrogen or lower alkyl, R(sup, 4) is hydrogen , lower acyloxyalkyl, lower acylthioalkyl, or heterocyclic lower thioalkyl, which may be substituted with one or more appropriate substituents, and R(sup, 5) is carboxy or protected carboxy; or a pharmaceutically acceptable salt thereof. |