Total Synthesis of All Eight Stereoisomers of ?-Tocopheryl Acetate. Determination of their diastereoisomeric and enantiomeric purity by gas chromatography
作者:Noal Cohen、Clifford G. Scott、Christian Neukom、Rocco J. Lopresti、Giuseppe Weber、Gabriel Saucy
DOI:10.1002/hlca.19810640422
日期:1981.6.10
All eight stereoisomers of α-tocopheryl acetate have been synthesized in a state of high chemical and stereoisomeric purity. Key chiral side-chain intermediates were prepared from (+)-(S)-3-hydroxy-2-methylpropanoic acid. New routes to (2R, 4′ RS, 8′ RS)-α-tocopheryl acetate, a mixture of four diastereoisomers, were also developed. A sensitive gas chromatographic method was developed to determine the
乙酸α-生育酚酯的所有八种立体异构体均以高化学和立体异构体纯度的状态合成。由(+)-(S)-3-羟基-2-甲基丙酸制备关键的手性侧链中间体。到新的路线(2 - [R,4' RS,8' RS)-α生育酚乙酸酯,四个非对映异构的混合物,也被开发的。开发了一种灵敏的气相色谱方法来测定α-生育酚样品作为甲基醚的非对映异构和对映异构纯度。首次确定天然存在的α-生育酚本质上是单一对映体(2 R,4'R,8'R),合成的全外消旋-α-生育酚是四个外消旋物的等摩尔混合物,而天然(E)-(7 R,11 R)-植物醇是非对映异构体和对映异构体均质的。