摘要 |
<p>A cephalosporin derivative of the formula:
<CHEM>
in which R<1> is any one of the C- 3 substituents from antibacterially-active cephalosporins known in the art; R<2> is any one of the C-4 substituents from antibacterially-active cephalosporins known in the art; R<3> is hydrogen, hydroxy, amino, C1-6alkyl, C1-6alkanoyl, C1-6alkoxy, C1-6alkonoylamino or C1-6alkylamino, phenylalkyl in which the alkyl part is C1-6 or phenyl in the latter two of which the phenyl is optionally substituted by methoxy:
A< is a radical of the formula:-
<CHEM>
in which R<4> and R<5>, which may be the same or different are hydrogen, halogen, cyano, hydroxy, carboxy, pyridyl, C1-6alkyl, C1-6aminoalkyl, C1-6hydroxyalkyl, C2-6alkoxycarbonyl, C2-10alkylaminoalkyl, C3-15dialkylaminoalkyl, or phenyl optionally substitued by 1 or 2 radicals selected from halogen, nitro, amino, hydroxy, carboxy, cyano, C1-6alkyl and C2-6alkoxycarbonyl; or R<4> and R<5> are joined to form a mono-, bi- or tricyclic carbocyclic ring system which may be non-aromatic, partially aromatic or fully aromatic, the aromatic part being optionally substituted by 1, 2 or 3 radicals selected from halogen, hydroxy, amino, cyano, carboxy, carbamoyl, nitro, ureido, C1-6alkyl, C1-6alkoxy, C1-6haloalkyl, C1-6alkylamino, C1-6hydroxyalkyl, C1-6aminoalkyl, C1-6alkanoylamino and C1-6azidoalkyl, C2-8dialkylamino, C2-10alkylaminoalkyl, C3-15dialkylaminoalkyl, C2-6cyanoalkyl, C2-6carboxyalkyl, C2-6carbamoylalkyl, and </p> |