Study on Synthesis of 2-(1-tert-Butoxycarbonylamino-2-methyl-buty!)-thiazole-4-carboxyiic acid methyl ester

摘要

2-(l-tert-Butoxycarbonylammo-2-methyl-butyl)-thiazole-4-carboxylic acid methyl ester, the chiral unit containing thiazole of a novel cyclic depsipeptide Lyngbyabellin A which exhibited moderate cytotoxicity against KB and LoVo cells, was synthesized from N-t-Boc-L-isoleucine and L-serrine methyl ester monohydrochloride in overall yield 15% through six steps, including condensation, TBS protection, thionation, deprotection, cyclodehydration and aromatization. The ee value of the title chiral thiazole unit is up to 98%.