| 摘要 |
Novel cephalosporin compounds having antibacterial activity, which are represented by the following compounds of the general formula (I), <IMAGE> (I) wherein R1 represents an amino group or a protected amino group; &cir& A represents a 5- or 6-membered heterocyclic ring containing therein 1 to 4 nitrogen, oxygen or sulfur atoms; R2 represents a normal alkyl group having 1 to 6 carbon atoms, a branched alkyl group having 3 to 6 carbon atoms, an alkoxyalkyl group having 2 to 6 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms; a cycloalkenyl group having 3 to 6 carbon atoms; an aromatic organic residue; a 3- to 6-membered heterocyclic ring containing 1 to 4 nitrogen, sulfur or oxygen atoms or, <IMAGE> wherein Ra and Rb each, which may be the same or different, represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms; R3 represents an organic residue containing an amino group or a protected amino group and a carboxyl group or a protected carboxyl group; X represents a sulfur atom or an oxygen atom; and R4 represents a hydrogen atom or a protective group of carboxyl group. The general formula (I) described above can also be used as physiologically acceptable addition salts. The compounds exhibit excellent intestinal absorption as well as high blood concentration and longer biological half-life.
|
