申请人:IMPERIAL CHEMICAL INDUSTRIES PLC
公开号:EP0304139A1
公开(公告)日:1989-02-22
The invention provides a novel process for the manufacture of [2,3-trans]-tetrahydro-5-hydroxy-3-hydroxymethyl-2-phenylfurans of the formula IIa, useful as intermediates in the production of novel (4-phenyl-1,3-dioxan-cis-5-yl)alkenoic acids of the formula I in which Ra and Rb are independently hydrogen, alkenyl, alkyl, halogenoalkyl, pentafluorophenyl, aryl or aryl-(1-4C)alkyl; or Ra and Rb together are polymethylene; Rc is hydroxy or (1-6C)alkanesulphonamido, A is vinylene, n is 1, Y is polymethylene, and benzene ring B bears various optional substituents. The compounds of formula I are obtained by the reaction of an aldehyde of formula II with an ylid to give an erythro-diol of formula III which is then cyclised to the required dioxane derivative of formula I. The aldehydes of formula II are obtained from the corresponding lactols of formula IIa, which are themselves obtained with the correct trans-stereochemistry by the inventive process using two selective reductions of a trans-phenylparaconic acid of formula V. The compounds of formula I are useful as therapeutic agents.
本发明提供了一种制造式 IIa 的[2,3-反式]-四氢-5-羟基-3-羟甲基-2-苯基呋喃的新工 艺,该工艺可用作生产式 I 的新型(4-苯基-1,3-二氧杂环-顺式-5-基)烯酸的中间体,其中 Ra 和 Rb 独立地为氢、烯基、烷基、卤代烷基、五氟苯基、芳基或芳基-(1-4C)烷基;或 Ra 和 Rb 共同为聚亚甲基;Rc 为羟基或(1-6C)烷磺酰胺基,A 为乙烯基,n 为 1,Y 为聚亚甲基,苯环 B 带有各种任选取代基。式 I 的化合物是通过式 II 的醛与酰基反应得到式 III 的赤二醇,然后将其环化成所需的式 I 的二噁烷衍生物。式 II 的醛是从相应的式 IIa 的内酯中得到的,而式 IIa 的内酯是通过本发明的工艺,使用式 V 的反式苯撑酸的两次选择性还原,以正确的反式立体化学反应得到的。