作者:Takashi Matsumoto、Sachihiko Imai、Takashi Hirata、Yutaka Fukuda、Tadashi Yamaguchi、Kazuhiro Inoue
DOI:10.1246/bcsj.56.3471
日期:1983.11
Partial methylation of (R)-6-hydroxy-3-(3-hydroxypropyl)-7-isopropyl-3,4-dimethylnaphtho[2,3-b]furan-2(3H)-one followed by benzylation afforded the 6-benzyloxy-3-(3-methoxypropyl) derivative, which was converted into the 9-acetyl derivative by the series of reactions; sodium borohydride reduction, acetylation, alkaline hydrolysis, and Jones oxidation. This was oxidized with m-chloroperbenzoic acid to give the 9-acetoxy-5,8-quinone derivative, which was further converted into the 5,6,8,9-tetraacetoxy-3-(3-hydroxypropyl) derivative by hydrogenolysis, reductive acetylation, and demethylation. The tetraacetate in pyridine was treated with o-nitrophenyl selenocyanate in the presence of tributylphosphine and the resulting selenide was oxidized with hydrogen peroxide to give the 3-allyl derivative. This was converted into (+)-coleon A lactone by alkaline hydrolysis and subsequent oxidation. Finally, (+)-coleon A lactone was reduced with sodium borohydride to give (+)-coleon A which was also obtained by lithium aluminium hydride reduction of the 3-allyl derivative.
(R)-6-羟基-3-(3-羟丙基)-7-异丙基-3,4-二甲基萘[2,3-b]呋喃-2(3H)-酮的部分甲基化,然后进行苄基化,得到6-苄氧基-3-(3-甲氧基丙基)衍生物,通过一系列反应转化为9-乙酰基衍生物;硼氢化钠还原、乙酰化、碱性水解和琼斯氧化。用间氯过苯甲酸氧化得到9-乙酰氧基-5,8-醌衍生物,通过氢解、还原进一步转化为5,6,8,9-四乙酰氧基-3-(3-羟丙基)衍生物乙酰化和去甲基化。在三丁基膦存在下,用邻硝基苯基硒氰酸酯处理吡啶中的四乙酸酯,并用过氧化氢氧化所得硒化物,得到3-烯丙基衍生物。通过碱性水解和随后的氧化将其转化为(+)-coleon A内酯。最后,用硼氢化钠还原(+)-coleon A内酯,得到(+)-coleon A,其也是通过氢化铝锂还原3-烯丙基衍生物得到的。