Syntheses of cystothiazole A and its stereoisomers: importance of stereochemistry for antifungal activity
作者:Makoto Ojika、Tatsuya Watanabe、Jianhua Qi、Tomoharu Tanino、Youji Sakagami
DOI:10.1016/j.tet.2003.10.078
日期:2004.1
The enantiocontrolled total syntheses of all the stereoisomers of a myxobacterial antibiotic, cystothiazole A, are described. The natural syn stereochemistry at the C4–C5 position was controlled by the asymmetric Evans aldol process, whereas the anti relationship was introduced by a modified Evans aldol methodology. Starting with a known aldehyde, the common substrate of the aldol reactions, cystothiazole
描述了粘细菌抗生素,巯基噻唑A的所有立体异构体的对映体控制的总合成。C4-C5位置的天然顺式立体化学是由不对称的Evans aldol过程控制的,而反关系是通过改良的Evans aldol方法引入的。从已知的醛开始,通过9个步骤合成醛醇缩合反应的常见底物,巯基噻唑A及其三种立体异构体。所有三种立体异构体即使在胱氨酸噻唑A剂量的2500倍的剂量下也没有显示出抗真菌活性。