By high-field two-dimensional 1 H NMR methods, the stereochemistry of the polyene chain has been assigned to four naturallyoccurring, isomeric mono- cis -lutein epoxides. The assignments corroborate our earlier suggestions according to which in Helianthus annuus the 9- cis isomer occurs without its 9′- cis counterpart. The stereomutation of natural lutein epoxide has also been studied.
摘要 通过高场二维 1 H NMR 方法,多烯链的立体化学已被指定为四种天然存在的异构单顺式叶黄素环氧化物。这些分配证实了我们之前的建议,即在向日葵中,9-顺式异构体出现而没有其 9'-顺式对应物。还研究了天然叶黄素环氧化物的立体突变。