Total syntheses of sterically locked phycocyanobilin derivatives with a 15Z-anti or a 15E-anti CD-ring component were performed toward elucidation of the stereochemistry and function of the chromophore in phytochromes. In the course of the construction of a sterically locked 15E-anti CD-ring component employing 5-tosylpyrrolin-2-one derivatives as the D-ring, the Ts group was found to be rearranged under acidic conditions to give a mixture of regioisomers, both of which could be transformed into the same CD-ring precursor via detosylation with a base followed by Wittig-like coupling reaction. In addition, a sterically locked 15E-anti biliverdin derivative was also synthesized.
对具有 15Z-抗或 15E-抗 CD 环组分的空间锁定藻蓝蛋白衍
生物进行全合成,以阐明光敏色素中生色团的立体
化学和功能。在使用5-
甲苯磺酰
吡咯啉-2-酮衍
生物作为D环构建空间锁定的15E-反
CD环组分的过程中,发现Ts基团在酸性条件下重排,得到区域异构体的混合物,两者都可以通过碱基去托基化,然后进行维蒂希样偶联反应,转化为相同的 CD 环前体。此外,还合成了空间锁定的15E-抗胆绿素衍
生物。