作者:Joaquín Tamariz、Héctor Quiroz-Florentino、Raúl Aguilar、Blanca Santoyo、Francisco Díaz
DOI:10.1055/s-2008-1066987
日期:——
The synthesis of naturally occurring furan derivatives rehmanones- A, B, and C is described. Diverse alternative synthetic strategies were developed for the preparation of these natural products. Conjugate addition of a furan to captodative alkene 1-acetylvinyl 4-nitrobenzoate was carried out under Lewis acid catalysis to give the corresponding adduct, which was transformed into rehmanones B and C
描述了天然存在的呋喃衍生物地黄酮 A、B 和 C 的合成。为制备这些天然产物开发了多种替代合成策略。在路易斯酸催化下,呋喃与捕获的烯烃 1-乙酰基乙烯基 4-硝基苯甲酸酯共轭加成得到相应的加合物,分别通过三步和两步转化为地黄酮 B 和 C。它们还通过丙酮与关键的呋喃-2-碳水化合物-醛中间体缩合制备,这些中间体可以很容易地从 D-果糖中获得。双呋喃地黄酮 A 不仅通过丙酮与 5-(甲氧基甲基)呋喃-2-甲醛的双重缩合在一步程序中获得,而且通过将后者与地黄酮 B 以高总产率缩合获得。