Stereocontrolled synthesis of ( S )-9- cis - and ( S )-11- cis -13,14-dihydroretinoic acid
作者:Belén Vaz、Rosana Alvarez、Angel R. de Lera
DOI:10.1016/j.tet.2016.05.006
日期:2016.7
Z,Z,E triene to the desired E,Z,E isomer was required prior to the synthesis of (S)-7 via a Suzuki cross-coupling. The same approach to (S)-9 led to substantial isomerization when the Suzuki cross-coupling was used as the last bond-forming reaction. As alternative, the two bond-forming steps were exchanged and the synthesis of (S)-9 was completed using the Z-selective Julia-Kocienski reaction.
已经立体选择性地合成了具有S构型的13,14-二氢视黄酸的9-顺式和11-顺式立体异构体,分别是(S)-7和(S)-9。前者最近被表征为类视黄醇X受体(RXR)的第一个内源性天然配体。烯丙基砜和醛的Julia-Kocienski反应用作连接步骤,可提供占目标分子整个侧链的三烯基酯的Z异构体。Z,Z,E三烯高度选择性和单向碘诱导的异构化为所需的E,ž,ê异构体之前(在合成时需要小号) - 7经由铃木交叉偶联。当将Suzuki交叉偶联用作最后一个形成键的反应时,用于(S)-9的相同方法导致大量的异构化。作为替代,交换两个键形成步骤并且使用Z-选择性的Julia-Kocienski反应完成(S)-9的合成。