| 摘要 |
<p>PURPOSE:To prepare the titled substance useful as a synthetic intermediate of penicillins and cephalosporins having antimicrobial activity, easily, by reacting alpha-oximino-beta-keto-gamma-halogenobutyric acid ester with a thiourea compound. CONSTITUTION:The objective compound of formula III (COOR<1> is carboxyl group which may be protected; R<2>NH is amino group which may be protected) is prepared by reacting the alpha-oximino-beta-keto-gamma-halogenobutyric acid ester of formulaI(X is halogen) with a thiourea compound of formula II in an organic solvent such as ethanol, tetrahydrofuran, etc. preferably in the presence of a base such as pyridine, triethylamine, etc. (the base is not necessary when R<2> is H) at room temperature or under refluxing condition, and if necessary, removing the protecting groups.</p> |
