N-chlorocarbonyl-N-methyl-3-methylcrotonamide 、 7-(D-α-aminophenylacetamido)-3-(1-methyl-1H-tetrazol-5-ylthio)methylceph-3-em-4-carboxylic acid 以56.7%的产率得到Sodium 7-[D-α-[3-(3-methylcrotonoyl)-3-methylureido]phenylacetamido]-3-(1-methyl-1H-tetrazol-5-ylthio)methylceph-3-em-4-carboxylate