METHOD OF PREPARATION OF DIHYDROPYRIDINE DERIVATIVES

摘要

PURPOSE: A method of preparation of amlodipine besylate is provided, which is characterized by a high yield, simple procedure and no isolation of amlodipine salt. CONSTITUTION: In one embodiment of the invention, sodium iodide is added to ethyl -4-(2-chloroethoxy)-acetoacetate(formula xiii) and acetone solution and mixture is heated and boiled for 13 hours. Inorganic material is filtered and filtered material is evaporated in vacuum. The remained oil is dissolved into chloromethane, the solution is washed by the water, dried and evaporated. the product is distilled in vacuum.