反应详情

7-Amino-3-hydroxycepham-4-carboxylic acid (1.09 g., purity 84.8%), trimethylsilylacetamide (5.3 g.), 2-methoxyimino-3,3-diethoxy-4-bromobutyric acid (syn isomer, 1.8 g.), phosphorus oxychloride (0.68 ml.), N,N-dimethylformamide (0.55 ml.) and methylene chloride (25 ml.) were treated in a similar manner to that of Example 25 (1) to give 7-(2-methoxyimino-3,3-diethoxy-4-bromobutyramido)-3-hydroxycepham-4-carboxylic acid (syn isomer, 1.1 g.).