| 摘要 |
NEW MATERIAL:A compound expressed by formula I (R<1> is H, lower alkyl, halogeno-lower alkyl, etc.; R<2> is amino which may be protected; R<3> is halogen, amino and hydroxyl which may be protected etc.; R<4> is tetrazolyl; the wavy line part is syn or anti isomer or a mixture thereof). EXAMPLE:( 3S,4R )-3-[2-( 2-Aminothiazol-4-yl )-(Z)-2-[( pyridin-3-yl) methoxyimino] acetamido]-4-methyl-1-(1H)-tetrazol-5-yl)-2-azetidinone. USE:An antimicrobial agent exhibiting improved activity against Gram-positive and Gram-negative bacteria. PREPARATION:A compound expressed by formula II is acylated with a compound expressed by formula III in or in the absence of a solvent at -50-+80 deg.C to give the aimed compound expressed by formula I. The reaction can be carried out in the presence of a base, e.g. NaOH or triethylamine. |
