申请人:NATIONAL RESEARCH DEVELOPMENT CORPORATION
公开号:EP0230381A2
公开(公告)日:1987-07-29
A process for the preparation of a compound of formula (I)
wherein X and Xʹ each represents hydrogen or together represent a bridging group -CH₂-, -CH₂-CH₂- or -O-; R¹ is a 6-carboxyhex-2-enyl group or a modification thereof in which the group is altered by one, or an appropriate combination of two of more, of the following: (a) alteration of the position of the double bond, with the proviso that in the modified group the double bond is not in the alpha-beta position relative to the ring; (b) reduction of the double bond; (c) alteration of the chain length through a decrease of one or two methylene groups or an increase of one to six methylene groups; (d) replacement of one or two methylene groups each separately by an oxygen or sulphur atom, with the proviso that in the modified group no oxygen or sulphur atom is in an alpha position relative to either a doubly bonded carbon atom or to the carboxy group or a derivative thereof and that at least 2 carbon atoms separate any pair of oxygen and/or sulphur atoms; and (e) formation of an amide, ester or salt derivative of the carboxy group; R² is an aliphatic hydrocarbon group or an aliphatic hydrocarbon group substituted by an aromatic group directly or through an oxygen or sulphur atom; and R³, R⁴, R⁵ and R⁶ are each hydrogen, or R³ and R⁴ together and/or R⁵ and R⁶ together represent the second bond of a carbon-carbon double bond; comprises effecting a Diels Alder reaction between a diene of formula (II) and a dienophile of formula (III)
wherein X, Xʹ and R² are as defined for (I); Y is R¹ or a precursor therefor in which a double bond is present and/or the terminal group is in different form, either being a free carboxy group rather than the carboxy group derivative present in R¹ or being a carboxy group derivative rather than the free carboxy group present in R¹; and R and Rʹ are either each hydrogen or together represent the third bond of a carbon-carbon triple bond; and where appropriate thereafter, in either order, reducing the double bond or bonds in the ring of the Diels Alder adduct and/or converting the group Y to the group R¹. The compounds prepared by this process are of value as intermediates for the preparation of biologically active compounds.
一种制备式(I)化合物的工艺
其中 X 和 Xʹ 各自代表氢或共同代表桥基 -CH₂-、-CH₂-CH₂- 或 -O-;R¹ 是 6-羧基己-2-烯基或其修饰基团,其中该基团通过以下一种或两种以上的适当组合而改变:(a) 改变双键的位置,但在改性基团中,双键不在相对于环的α-β位置上; (b) 减少双键; (c) 通过减少一个或两个亚甲基或增加一至六个亚甲基来改变链长;(d) 用一个氧原子或硫原子分别取代一个或两个亚甲基,但条件是在修饰后的基团中, 没有一个氧原子或硫原子相对于双键碳原子或羧基或其衍生物处于α位,并且任何 一对氧原子和/或硫原子之间至少有两个碳原子相隔;(e) 形成羧基的酰胺、酯或盐衍生物; R² 是脂肪族烃基或直接或通过氧原子或硫原子被芳香族取代的脂肪族烃基;和 R³、R⁴、R⁵ 和 R⁶ 分别是氢,或 R³ 和 R⁴ 一起和/或 R⁵ 和 R⁶ 一起代表碳-碳双键的第二个键;包括在式 (II) 的二烯和式 (III) 的亲二烯之间进行 Diels Alder 反应
其中X、Xʹ和R²与(I)的定义相同;Y是R¹或其前体,其中存在双键和/或末端基团的形式不同,或者是游离的羧基而不是R¹中存在的羧基衍生物,或者是羧基衍生物而不是R¹中存在的游离羧基;R和Rʹ或者各自为氢,或者共同代表碳-碳三键的第三个键;此后,在适当的情况下,按照任一顺序,还原Diels Alder加合物环中的双键和/或将基团Y转化为基团R¹。该工艺制备的化合物具有作为中间体制备生物活性化合物的价值。