砂贝母中异甾体生物碱类成分的研究

利用各种柱色谱和高效液相色谱等分离纯化方法,从砂贝母鳞茎中分离得到6个异甾体生物碱类化合物.根据质谱、一维/二维核磁共振谱和X射线单晶衍射等技术鉴定了它们的结构,分别为karelinine(1),5-epikarelinine(2),27-epiebeienine (3), ebeienine (4), persicanidine B (5)和heilonine (6),其中化合物1～3为新化合物.化合物1是贝母属中罕见的5β-jervine型异甾体生物碱,具有A/B环顺式稠合方式.化合物1和2也是贝母属中首次发现的具有15α-OH取代的jervine型生物碱.     

Cudratricusxanthone B的全合成

以价廉易得的2,4-二羟基苯甲酸为起始原料,通过Claisen重排和选择性脱甲基等8步反应,以3.1%的总收率首次完成了具有生物活性的异戊烯基氧杂蒽酮类天然产物cudratricusxanthone B(1)的全合成,为该化合物进一步的生物活性研究奠定了物质基础.同时还合成得到另一氧杂蒽酮化合物2,证实文献报道的氧杂蒽酮类天然产物staudtiixanthone D结构鉴定有误.     

New Myrsinol Diterpenes from Euphorbia prolifera

Four new myrsinol diterpenes, euphorprolitherins A-D (1-3, 5), were isolated from the ethanolic extract of the root of Euphorbia prolifera, along with a known one, SPr5 (4). The structures were elucidated on the basis of their spectroscopic evidences. The structure and relative stereochemistry of 1 were confirmed by X-ray crystallography.