| 摘要 |
<p>FIELD: organic chemistry, antibiotics, chemical technology. SUBSTANCE: invention relates to new intermediate derivatives of cephalosporin of the formula (IA) wherein: a) Ra means hydrogen atom or silyl group; Rb means group of the formula -ORe wherein Re means hydrogen atom or alkyl; Rc and Rd mean in common a bond; or b) Ra and Rb mean hydrogen atom or silyl group; Rb and Rc mean in common imino-group of the formula = N-Y wherein Y means phenyl; or c) Rd means hydrogen atom or silyl group; Ra means hydrogen atom if Rd means hydrogen atom; either Ra means hydrogen atom or silyl group if Rd means silyl group; Rb and Rc mean in common oxo-group; silyl group means tri(lower alkyl)silyl group; in free form or as a salt as an intermediate substance for preparing cephalosporins. Invention relates to method for preparing cephalosporin that involves: 1) interaction of compound of the formula (1A) wherein R means silyl group with compound of the formula (XI) or with compound of the formula (XII) wherein R5/ and R6 are similar or different and mean hydrogen atom or organic group; either R5 and R6 mean in common substituted or unsubstituted ring; R10 means aryl or lower alkyl; Cat+ means alkaline metal cation or protonated form of strong organic base to form compound of the formula (XIII) wherein R5, R6 and R are given above; 2) desilylation of compound of the formula (XIII) to form compound of the formula (VI) wherein R5 and R6 are similar or different and mean hydrogen atom or organic group; either R5 and R6 mean in common substituted or unsubstituted ring; 3) conversion of compound of the formula (VI) to cephalosporin. Invention provides preparing new intermediate derivatives of cephalosporin. EFFECT: improved preparing method. 7 cl, 15 ex</p> |
