Preparation method of praziquantel

The invention relates to the technical field of medicine and chemical industry, and provides a praziquantel preparation method, which comprises: S1, carrying out a primary condensation reaction on beta-phenylethylamine and chloroacetyl chloride in an organic solvent in the presence of an alkaline substance to obtain a first intermediate; s2, carrying out secondary condensation reaction on the first intermediate and chloroacetaldehyde dimethyl acetal to obtain a second intermediate; s3, cyclizing the second intermediate under the action of an acid catalyst to obtain a third intermediate; and S4, carrying out a substitution reaction on the third intermediate and cyclohexyl formyl chloride in the presence of an alkaline substance to obtain praziquantel. Through the technical scheme, the problems of complex operation, high cost, low yield and low purity of a praziquantel production process in the prior art are solved. 本发明涉及医药与化工技术领域，提出了一种吡喹酮的制备方法，包括以下步骤：S1、将β-苯乙胺与氯乙酰氯于碱性物质存在下，在有机溶剂中进行一次缩合反应，得到第一中间体；S2、将所述第一中间体与氯代