| 摘要 |
<p>NEW MATERIAL:A compound of formulaI[X is H, R3CO- (R3 is H, straight or branched alkyl), protecting group that is easily removable; R1, R2 are H, 1-10C alkyl, which may be substituted with hydroxyl or mercapto groups; Y is group of formula II or III; n is 1-3]. EXAMPLE:7beta-[2( 2-L-Leucyl-L-phenylalanineamidethiazol-4-yl )-(Z)-2-methoxyiminoacetamide]cephalosphoranic acid. USE:Antibiotic: it is orally given to develop strong antibiotic activity in living bodies. PREPARATION:The N-terminal of the oligopeptide is protected and the direct condensation with a cephalosporin of formula IV is conducted or the condensation reaction is effected using a condensation reagent. Or the protected peptide is previously converted into a reactive derivative and subjected to reaction to give the objective compound of formulaI.</p> |
