| 摘要 |
<p>PURPOSE:A specific compound is treated with a halogenating agent and converted into an imidoyl halide, then the product is treated with N-oxide and methanol susequently to give the titled compound of an antibiotic with a wide range of antibiotic spectrum. CONSTITUTION:A compound of formula I [R<1> is alkyl, alkenyl; R<2> is H, carboxyl protecting group; R<3> is acetoxymethyl] such as 7beta-phenoxyacetamide-3-methyl-3- cephem-4-carboxylic acid is converted into an imidoyl halide of formula II (X is halogen) by treating it with a halogenating agent. Then, the product is treated with an N-oxide of formula III (R<4> is 2-, 4-OH, alkoxy) or formula IV to give a pyridone of formula V (R<5> is formula VI, VII) or quinolone. Finally, the product is treated with methanol to give a compound of formula VIII such as 7beta-phenoxyactamide-7alpha-methoxy-3-methyl-3-cephem-4-carboxylic methyl ester.</p> |
