| abstract |
Cephalosporins of formula (I) and their keto tautomers and salts (where Y is H or OMe; A is a 2,3-dihydro-2 (A'-imino)-4-thiazolyl gp., where A' is H, COCH2Cl, COCH2Br, COOCH2CCl3, CHO or trityl, or A can also be phenyl, 4-hydroxyphenyl, 3,4-dihydroxyphenyl or 2- or 3-thienyl when Y is OMe; D is H, OCOMe, OCONH2, pyridinio, 4-carbamoylpyridino or SHet, where Het is 1,3,4-thiadiazol-5-yl 2-methyl-1,3,4-thiadiazol-5-yl, 1,2,4-thiadiazol-5-yl, 3-methyl, -1,2,4-thiadiazol-5-yl, 5,6-dioxo-4H-1,2,4-traizin-3-yl, 4-methyl-5,6-dioxo- 1,2,4-triazin-3-yl or 1-D'-tetrazol-5-yl, where D' is vinyl, allyl, 1-4C alkyl, 2,3-hydroxypropyl or (CH2)nR1, where n= 1-3 and R1 is OH, NH2, NMe2, NHCOMe, CONH2, NHCONH2, SO2NH2, NHSO2NH2, COMe, NHSO2Me, CN, NHSO3H, SO2Me, SOMe or a carboxylic or sulphonic acid gp; R is NHR2, where R2 is a 3-pyridyl, 5-pyrimidinyl, 2-thienyl, 2-furylmethyl, 2-thienylmethyl, 2-imidazolylmethyl, 2-thiazolylmethyl, 3-pyridylmethyl or 5-pyrimidinylmethyl gp. op.t substd. by Cl, Me, NHCOMe, OH, SOMe, SO2Me, CONH2 or SO2NH2; E is H or a protecting gp.). |