| 摘要 |
The present invention provides a compound of the formula (I): <CHEM> or a pharmaceutically acceptable salt or an ester thereof wherein R<1> and R<2> each represent a hydrogen atom or an organic group bonded via a carbon atom to the carbapenem ring, R<3> and R<4> each represent an organic group bonded via a carbon atom to the carbapenem ring, or R<3> and R<4> are joined so as to form together with the carbon atom to which they are attached an optionally substituted C3-7 cycloalkyl or optionally substituted heterocyclyl ring, and R<5> is a hydrogen atom, a group SH, or a group S(O)nR<6> wherein n is zero or one and R<6> is an organic group bonded via a carbon atom to the sulphur atom; excluding benzyl 4,4-dimethyl-7-oxo-1-azabicyclo[3.2.0.]hept-2-ene2-carboxylate. These compounds are useful as antibacterial agents. |
