| 摘要 |
<p>NEW MATERIAL:A compound expressed by formula I{R<1> is H, amino protecting group or acyl; R<2> is H or lower alkyl; R<3> is H, lower alkoxy, lower alkylthio or formamide; R<4> is (protected) carboxyl or carboxylate; R is -NHR<5>, formula II [R<5> and R<6> are (protected) OH, cyano, sulfo, etc.], etc.; n is 1 or 2}. EXAMPLE:(3R,5R,6R)-3-(3-Benzilideneamino-2-oxoimidazolidin-1-y-1)-3-(p- nitrobenzyloxycarbonyl)-7-oxo-6-phenylacetamide-4-thi-a-1- azabicyclo[3,2,0]heptane. USE:An antimicrobial agent being stable to beta-lactamase and strong to resisting germ. PREPARATION:A compound expressed by formula III (R<1a>CO- is acyl; R<4a> is protected carboxyl) is subjected to ring closing reaction in the presence of a base to provide the compound expressed by formula IV.</p> |
