(+)-(1R,2R,3R)-Presqualene diphosphate (PSPP) is an intermediate in the biosynthesis of squalene from farnesyl diphosphate (FPP). The natural 1R,2R,3R enantiomer was synthesized from farnesol in nine steps with greater than or equal to 98% ee. The key step in the synthesis was the stereoselective intramolecular cyclopropanation of farnesyl diazoacetate (5) upon treatment with a chiral rhodium catalyst to give (-)-lactone 6.
(+)-(1R,2R,3R)-Legalene 二
磷酸(P
SPP)是法呢烯二
磷酸(FPP)
生物合成鲨烯过程中的一个中间体。天然的1R,2R,3R 对映异构体通过从
法呢醇出发的九步合成路线制得,纯度超过或等于98% ee。合成的关键步骤是法呢基
叠氮醋酸酯(5)在手性
铑催化剂作用下选择性的分子内
环丙烷化,生成(-)-环酯6。