吡罗昔康工艺的改进

Improvement of Piroxicam Synthesis

糖精钠与氯乙酸乙酯缩合得3-氧代-1,2-苯并异噻唑啉-2-乙酸甲酯-1,1二氧化物,甲醇钠作碱,经N-甲基化,得2-甲基-3,4-二氧-4-氧化-2H-1,2-苯并噻嗪-3-羧酸甲酯-1,1-二氧化物,再与2-氨基吡啶反应得吡罗昔康。重拍扩环采用一勺烩的合成方法,通过酸碱沉淀进行精致后,总收率达到72%。

Take saccharin sodium chloride and ethyl condensation to give 3 - oxo - 1 ,2 - benzisothiazol - 2 - acetate 1,1 - dioxide, sodium methoxide as the base, the N - methylated to give 2 - methyl - 3,4 - dioxo - 4 - oxidation - 2H - 1, 2 - benzothiazine - 3 - carboxylate 1,1 - dioxide, then with a 2 - amino -pyridine was piroxicam. Used one pot synthesis method for expandase remake, the total yield of 72%.