KR880000449A - Method for preparing cefem derivatives - Google Patents

Abstract

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Description

Method for preparing cefem derivatives

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Claims (7)

In the organic solvent, the compound of the following structural formula (II) and the organic acid of the following structural formula (III) are reacted with the organic base in the presence of the condensing agent of the following structural formula (IV) or (V) Process for preparing cefem derivatives. Wherein R ¹ represents hydrogen or a metal salt and R ² represents hydrogen, methyl, halogen acetoxymethyl or CH ₂ SR ³ , where R ³ contains 1-4 heteroatoms and may be substituted with lower alkyl groups Or 6-membered bicyclic), and R ⁴ represents alkyl or an alkyl group. The method according to claim 1, wherein the acylation is carried out using a condensing agent of the formula (IV) or (V) and an organic base without protecting the amino group of the organic acid represented by the formula (III). A process according to claim 1, wherein the condensing agent of formula IV is dialkyl 2-pyridone-1-yl phosphate. The method of claim 1 wherein the condensing agent of formula (V) is di-2-pyridyl sulfate. The organic base according to claim 1, wherein the organic base used in the presence of a condensing agent of the general formula (IV) or (V) is triethylamine, pyridine, dimethylamine, isopropylamine, N, N-dimethylaniline 4-N, N -Dimethylamino pyridine and the like. 4. A process according to claim 3, wherein the condensing agent of formula IV is reacted with N-hydroxy-2-pyridone and dialkyl fluorphosphate. The process according to claim 4, wherein the condensing agent of formula (V) is prepared by reacting thionyl chloride with 2-hydroxypyridine. ※ Note: The disclosure is based on the initial application.