Biosynthesis of unusual acyclic isoprenoids in the Alga Botryococcus braunii
作者:Fred R. Wolf、Esther K. Nemethy、Jonathan H. Blanding、James A. Bassham
DOI:10.1016/s0031-9422(00)84886-4
日期:1985.1
in the C31, C32 and C34 botryococcenes. The results of pulse-chase experiments implicated the C30 botryococcene as the precursor of the higher homologues; during the chase, loss of radioactivity from the C30 compound was accompanied by a concomitant increase in the labelling of the C31 and C32 compounds. This study provides further evidence that the relatively slow growth of Botryococcus in culture
Synthesis of Enantioenriched Tertiary Boronic Esters from Secondary Allylic Carbamates. Application to the Synthesis of C30 Botryococcene
作者:Alexander P. Pulis、Varinder K. Aggarwal
DOI:10.1021/ja303022d
日期:2012.5.2
reaction has been explored and found to embrace a broad range of both allylic carbamates and boronic esters. The methodology has been applied to an eight-step, stereoselective synthesis of each of the diastereoisomers of C30 botryococcene.
对映体富集的仲烯丙基氨基甲酸酯已被 sBuLi 去质子化并与硼酸酯反应。与其他亲电试剂相比,观察到了高α-选择性,并且硼酸盐络合物的形成几乎完全保留了立体化学。硼酸酯复合物经历了立体有择的 1,2-迁移,产生了具有更高 er (>98:2) 的叔烯丙基硼酸酯。该反应的范围已被探索并发现包括广泛的烯丙基氨基甲酸酯和硼酸酯。该方法已应用于 C30 葡萄球菌烯的每种非对映异构体的八步立体选择性合成。