Bioactive and Other Sesquiterpenes from Chiloscyphus rivularis
摘要:
Bioassay-directed fractionation of the methyl ethyl ketone extract of Chiloscyphus rivularis yielded five new sesquiterpenes, 12-hydroxychiloscyphone (2), chiloscypha-2,7-dione (3), 12-hydroxychiloscypha-2,7-dione (4), chiloscypha-2,7,9-trione (5), and rivulalactone (6) in addition to the known sesquiterpenes, 4-hydroxyoppositan-7-one (7), chiloscyphone (1), and isointermedeol (8). The structure and stereochemistry of rivulalactone, a novel trinorsesquiterpene, was confirmed by its synthesis starting from 1. Compound 2 showed selective bioactivity in our yeast-based DNA-damaging assay and cytotoxicity to human lung carcinoma cells.
Total Synthesis of (−)-Chiloscyphone, Sesquiterpenoid Isolated from the Liverwort. Absolute Configuration of (−)-Chiloscyphone and (+)-Chiloscypholone
作者:Motoo Tori、Takeshi Hasebe、Yoshinori Asakawa
DOI:10.1246/bcsj.63.1706
日期:1990.6
The absolute configurations of (−)-chiloscyphone and (+)-chiloscypholone isolatedfrom the liverwort Chiloscyphus polyanthos and C. pallescens respectively, have been determined by the total synthesis of the optically active compound. The 1,4-addition of vinylmagnesium bromide to 3,4-dimethyl-2-cyclohexenone in the presence of copper(I) bromide-dimethyl sulfide complex and the subsequent aldol condensation
The total syntheses of chiloscyphone (1) and isochiloscyphone (2) have been achieved. Furthermore, the synthetic intermediate 5 shows biological activity against methicillin-resistant Staphyrococcus aureus, and compounds 5, 17, and 18, display imipenem-type activity. The tricyclic lactone framework, which includes an α,β-unsaturated ketone moiety, might play a crucial role in the anti-MRSA activity
Total Synthesis of Liverwort Sesquiterpene Ketone (±)-Chiloscyphone<i>via</i>Intramolecular Aldol Condensation
作者:Motoo Tori、Takeshi Hasebe、Yoshinori Asakawa
DOI:10.1246/cl.1988.2059
日期:1988.12.5
(±)-Chiloscyphone, a sesquiterpene ketone isolatedfrom the liverwort, has been synthesized starting from 3,4-dimethyl-2-cyclohexen-1-one via intramolecular aldol condensation.
The structure of chiloscypholone, a sesquiterpenoid with a novel carbon skeleton, from the liverwort Chiloscyphus pallescens. A revised structure for chiloscyphone
作者:Joseph D. Connolly、Leslie J. Harrison、David S. Rycroft
DOI:10.1039/c39820001236
日期:——
Chiloscypholone, a bicyclic sesquiterpenoidfrom the liverwortChiloscyphuspallescens, is shown to have the structure (3), with a novel ring-contracted eremophilane skeleton, on the basis of chemical and spectroscopic (mainly from 1H and 13C n.m.r. spectra) evidence; dehydration of (3) gives two isomeric dienones, one of which is chiloscyphone, originally isolated from C. polyanthus, now assigned
基于化学和光谱学(主要来自1 H和13 C nmr光谱)的证据显示,地氯菊酯(Closlosphus pallescens)的双环倍半萜类化合物Chiloscypholone具有结构(3),具有新颖的环状收缩的艾美龙骨架。(3)的脱水得到两个异构的二烯酮,其中之一是最初从聚花金丝桃中分离出来的香豆素,现在被赋予了改型的结构(4)。
Piers, Edward; Tse, Hoi Lun Allan, Canadian Journal of Chemistry, 1993, vol. 71, # 7, p. 983 - 994