| 摘要 |
<p>PURPOSE:To prepare the titled substance useful as an antibiotic substance effective to wide variety of microorganisms, by reacting 4-pyridylthioacetic acid alkali metal salt directly with a specific 7-aminocephalosporanic acid, an inorganic base, etc., and eliminating the carboxyl-protecting group of the product. CONSTITUTION:The titled substance can be prepared by (1) reacting a compound of formula I (M is alkali metal), a compound of formula II (R4 is ester residue), a compound of formula III (R1 is lower alkyl, benzyl, etc.; X is halogen; Y is halogen, etc.), and an inorganic base (e.g. Na2CO3, K2CO3, etc.), and (2) treating the resulted compound of formula IV with trifluoroacetic acid, etc. to eliminate the ester residue. The reaction can be carried out with simple procedure without converting the 4-pyridylthioacetic acid to a reactive derivative. Since a tertiary amine is not used in the reaction, the isomerization of 7-aminocephalosphoranic acid ester scarcely occurs.</p> |
