Total synthesis of (+)-10,10-difluorothromboxane A2 and its 9,11 and 15 stereoisomers
作者:Stanislaw Witkowski、Y. Koteswar Rao、Ramiya H. Premchandran、Perry V. Halushka、Josef Fried
DOI:10.1021/ja00048a017
日期:1992.10
An efficient total synthesis of the biologically highly active, stable (+)- 10, 10-difluorothromboxane A 2 , possessing the absolute configuration of TXA 2 , from the chiral synthon (-)-5 is described. The key intermediate, the aldehyde 25, is prepared in 16 steps with a total yield of 8.8%, which compares with 1.95% in 14 steps by our previously reported chemical-enzymatic route. Diastereoselectivity
描述了从手性合成子 (-)-5 高效全合成具有 TXA 2 绝对构型的生物高活性、稳定 (+)- 10, 10-二氟血栓烷 A 2 。关键中间体醛 25 分 16 步制备,总产率为 8.8%,而我们之前报道的化学-酶促路线分 14 步制备的总产率为 1.95%。除了导致 13 和 14 的 Reformatsky 反应之外,所有步骤的非对映选择性都很高。 然而,两种差向异构体都已有效地转化为 25