分子内环加成的甾体全合成

Total Synthesis of Steroids through Intramolecular Cycloaddition

近年来,分子内环加成反应已广泛用于甾体化合物全合成,其主要一步是由取代的苯并环丁烯热裂而成的5,6-二亚甲基-1,3-环己二烯发生区域专一和立体选择性的环加成反应,构成甾体骨架。现在用此法已合成了一系列消旋和光学活性的甾体化合物。

This paper reviews the recent developments in intramolecular cycloadditionreaction widely used in total synthesis of steroidal compounds.The key step of this meth-od is regiospecific and stereoselective cycloaddition of substituted o-quinodimethanes de-rived in situ from the corresponding benzocyclobutenes. A large number of estrane and pregnane type steroids as well as optically active ster-oids have been synthesized by this method recently.