利可君合成工艺的改进

目的改进利可君合成工艺。方法以胱氨酸、苯乙酸乙酯和甲酸乙酯为原料，以还原铁粉为催化剂合成L-半胱氨酸盐酸盐，以石油醚为溶剂在超声条件下合成α-甲酰基苯乙酸乙酯，两者以乙醇为溶剂环合反应制备利可君。结果L-半胱氨酸盐酸盐收率99．51％，α-甲酰基苯乙酸乙酯反应时间4h，收率92．6％，利可君合成总收率75．3％。结论以胱氨酸为原料降低了合成成本，超声条件下合成α-甲酰基苯乙酸乙酯缩短了生产周期，收率提高9．2％，利可君总收率比传统工艺提高了22．5％～27．2％，以乙醇为溶剂环合，生产更安全环保。

Process Improvement on Synthesis of Leucogen

Objective To improve the synthesis process of leucogen. Methods With cystine, ethyl phenylacetate and ethyl formate as the material, L-cysteine hydrochtoride was synthesized with iron as catalyst. Ethyl α-formylphenylacetate was prepared with the solvent of benzene on the condition of ultrasonic. Leucogen was synthesized by the cyclization reaction of L-cysteine hydrochloride with ethyl α-formylphenylacetate in the solvent of alcohol. Results The yield of L-cysteine hydrochloride was 99.51%. The reaction time of ethyl α-formylphenylacetate was 4 h, and the yield was 92.6%. The total yield of leucogen was 75.3%. Conclusion The cost of synthesis can be decreased with the material of cystine. The reaction time of ethyl α-formylphenylacetate can be shortened and the yield can be increased by 9.2% on the condition of ultrasonic. The total yield of leucogen can be increased 22.5%427.2% with the manufacture process of more safety and environmental protection.