Arylmethyl- and cyclohexenylmethyl- penicillins, substituted on the .alpha.carbon atom of the side chain by a 2,3-disubstituted imidazolidinylcarbamido or a 2,3-disubstituted imidazolidinylthiocarbamido group, or by the corresponding 2,3-disubstituted 1,3-diazacyclohexylcarbamido or thiocarbamido groups are anti-bacterial agents.
The present invention relates to processes for the preparation of new imidazoles, especially of 4- or 5-nitro-imidazoles, substituted by tetrahydroimidazoles which may be substituted and to such compounds which are valuable chemotherapeutica in the treatment of gram-negativ bacteria, protozoa and worms.