Process for the preparation of a pharmacologically active sulphonylurea derivative. The present invention relates to a method of preparing N-{4-[2-(5-methyl-pyrazinyl-2-carboxamido)-ethyl)- benzenesulphonyl}-N'-cyclohexylurea or glipizide, which has the chemical structure (I), by letting 4-[2-(5-methylpyrazinyl)-2-carboxamido)-ethyl]- benzenesulphonamide with the chemical structure (II), where R1 = NH2, react with N-cyclohexyl trichloroacetamide with the chemical structure (III), where R2 = NHCOCCl3, according to the following reaction scheme: The reaction is carried out in the presence of a polar, aprotic solvent such as N-methylpyrrolidone (NMP), N,N- dimethylformamide (DMF), N,N-dimethylacetamide (DMA) or dimethylsulphoxide (DMSO) under anhydrous conditions in the presence of a base such as an alcoholate, amide or hydride of an alkali metal. The reaction mixture is heated under reflux condensation to 40-100°C and the reaction is going on for 2-5 hours.
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