| abstract |
The present invention relates to novel cefem compounds of the formula wherein Q is a carbon or nitrogen atom; X is an oxygen atom or a nitroalkyl or cyanoimine group, provided that X cannot be an oxygen atom when Q is a carbon atom; R 1 is a hydrogen atom, a lower alkyl group, or a lower alkyl group which may be substituted by fluorine, or a carboxyl group, or an inorganic cation of a salt thereof; and R2 and R3 are independently a hydrogen atom or a lower alkyl group; or a pharmaceutically acceptable salt thereof. The compounds of the present invention have strong antibacterial activity against gram-negative bacteria, in particular Pseudomonas, and a longer half-life than known cefen compounds. |