| abstract |
1. A method for producing cephalosporin derivatives of the general formula H-pHCONH 4 A D-Nx g CHg-B-Ve with EO NH where A is 4-hydroxyphenyl or 2-thienyl; R is a radical of the general formula. Pg a or n-Rt RI pyridylmethylamino group; Het - 4-methyl-5,6-dioxo-1,2,4 triazin-3-yl, 1-vinyl tetrazol-5-yl or a group of the formula NX II (IVI) X2 where Rj is hydroxyl, amino, dimethylamino, acetylamino, aminocarbonyl , aminocarbonylamino, aminosulfonyl, aminosulfonylamino, oxysulfonylamino, methylsulfonyl or a carboxylic or sulfonic acid group; p is 1 or 2, or the group SP (CH2) j, R 2 is ethyl; E is hydrogen, or a protecting group such as an ester, or their salts, if E is hydrogen, characterized in that the 7-aminocephalosporanic acid derivative of the general formula YaoH. ISJ Nj CHrS-Het SP O COOE f in which Het and E have the indicated values, is reacted with a ureido VI carboxylic acid of the general formula K-ad-co-in-cn-soon A where A and R have the indicated values, or its salt , or a reactive derivative in the solvent, followed, if necessary, by deprotection and release of the desired product c. in free form or in salt form. |