Isomerization of all-(<i>E</i>)-Retinoic Acid Mediated by Carbodiimide Activation - Synthesis of ATRA Ether Lipid Conjugates
作者:Mikkel S. Christensen、Palle J. Pedersen、Thomas L. Andresen、Robert Madsen、Mads H. Clausen
DOI:10.1002/ejoc.200901128
日期:2010.2
1-O-hexadecyl-sn-phosphatidylcholine with all-(E)-retinoic acid, DCC and DMAP resulted in poor acylation and caused (Z)/(E) isomerization of the α–β double bond. In the presence of a proton source, the carbodiimide-activated all-(E)-retinoic acid undergoes fast isomerization to give a final mixture of (13E)/(13Z) isomers in a 3:1 ratio. Similar treatment of (13Z)-retinoic acid leads to the same isomer ratio.
用全-(E)-视黄酸、DCC 和 DMAP 处理溶血脂 1-O-十六烷基-sn-磷脂酰胆碱导致酰化不良并导致 α-β 双键的 (Z)/(E) 异构化。在质子源的存在下,碳二亚胺活化的全-(E)-视黄酸进行快速异构化,得到 (13E)/(13Z) 异构体的最终混合物,比例为 3:1。(13Z)-视黄酸的类似处理导致相同的异构体比例。通过使用 Mitsunobu 反应成功地避免了异构化,该反应提供了全-(E)-视黄酸 sn-2-共轭到磷脂酰胆碱和磷脂酰甘油醚脂质的有效合成。