工布乌头根中的二萜生物碱

工布乌头（ＡｃｏｎｉｔｕｍｋｏｎｇｂｏｅｎｓｅＬａｕｅｎｅｒ）系毛茛科乌头属植物,分布于西藏及四川西部,其块根有剧毒,泡酒外用可治疗跌打损伤和毒虫咬伤［１］。Ｙｕｅ等［２］、王锋鹏等［３］和庞志功等［４］曾从该植物分离到５个二萜生物碱。本文报道从四川产工布乌头的块根分离出的４个二萜生物碱。根据ＭＳ、１Ｈ－ＮＭＲ、１３Ｃ－ＮＭＲ等波谱分析,确定其中一个微量成分为新Ｃ１９－二萜生物碱,命名为工布生（ｋｏｎｇｂｏｅｎｓｉｎｅ,１）另外３个已知化合物分别鉴定为瓜叶乌碱甲素（２）、印乌碱（３）和它拉乌头胺…     

卢氏香茶菜乙素的结构

从卢氏香茶菜叶的乙醚提取物中分得一个新的二萜化合物,卢氏香茶菜乙素(ludongnin B),其结构经各项光谱数据确定为(1)式。     

滇南草乌的化学成分研究（Ⅱ）

接前文此报告推定了从滇南草乌中分到的碱9—12的结构分别为8-去乙酰黄草乌碱甲(9),talatizidine(10),condelphine(11)和滇乌碱(12)。碱9为首次报告的新化合物,命名为南乌碱乙(austroconitine B)(9)。     

天然C_(19)-二萜生物碱的核磁共振谱(Ⅰ)

本文将迄今为止已发表的230余个天然C_(19)-二萜生物碱按其结构和核磁共振波谱特征分为8个类型,着重叙述了每个类型的结构和核磁共振波谱,并对某些立体构型与~(13)C-NMR化学位移的关系进行了讨论。最后以表格的形式报导了每个天然C_(19)-二萜生物碱的结构及其主要的植物来源,并将其中170余个生物碱的~(13)C-NMR化学位移数据分门别类,整理成表,以便于对相似化合物的~(13)C-NMR进行比较,这样对于分析鉴定C_(19)-二萜生物碱将大有帮助。第一部分包含两个主要的类型——乌头碱型和牛扁碱型,其它类型待第二部分进行讨论。     

贵州冬凌草素的结构

从贵州省遵义地区产冬凌草[Rabdosia rubescens(Hemsl,)Hara]叶中分得一个新的二萜化合物,命名为贵州冬凌草素(guidongnin),其结构经各项光谱和化学证据确定为对映-6,7-螺断-6,19-γ-内酯环-7,20-δ-内酯环-16-贝壳杉烯-11β,15α-二醇(1)。     

Diterpenoid Alkaloids from the Roots of Aconitum kongboense Lauener

Four diterpenoid alkaloids were obtained form the roots of Aconitum kongboense Lauener. Among them, one is a new alkaloid, kongboensine (1), and the structure has been elucidated by spectral evidence. The others were identified as guayewuanine A (2), indaconitine (3) and talatisamine (4) respictevely. 2 and 3 were isolated from this plant for the first time.     

Isolation and structure characterization of two new diterpenoids from Clerodendrum bungei

Two new diterpenoids, 3β-(β-d-glucopyranosyl)isopimara-7,15-diene-11α,12α-diol (1), and 16-O-β-d-glucopyranosyl-3β-20-epoxy-3-hydroxyabieta-8,11,13-triene (2), along with three known ones were isolated from the roots of Clerodendrum bungei. These compounds were purified, and their structures were elucidated by extensive spectroscopic analyses, especially 2D NMR experiments. All compounds were evaluated for cytotoxicity against several tumor cell lines.     

Structures of the novel α-glucosyl linked diterpene glycosides from Stevia rebaudiana

From the commercial extract of the leaves of Stevia rebaudiana, two new minor diterpene glycosides having α-glucosyl linkage were isolated besides the known steviol glycosides including stevioside, steviolbioside, rebaudiosides A–F, rubusoside and dulcoside A. The structures of the two compounds were identified as 13-[(2-O-(3-α-O-d-glucopyranosyl)-β-d-glucopyranosyl-3-O-β-d-glucopyranosyl-β-d-glucopyranosyl)oxy] ent-kaur-16-en-19-oic acid β-d-glucopyranosyl ester (1), and 13-[(2-O-β-d-glucopyranosyl-3-O-(4-O-α-d-glucopyranosyl)-β-d-glucopyranosyl-β-d-glucopyranosyl)oxy] ent-kaur-16-en-19-oic acid β-d-glucopyranosyl ester (2), on the basis of extensive NMR and MS spectral data as well as chemical studies.     

Two new penterpenoid saponins and a new diterpenoid glycoside from Hemsleya chinensis

Two new penterpenoid saponins, hemsloside-Ma4 (1) hemsloside-Ma5 (2), and a new diterpenoid glycoside, hemsloside-Ma6 (3), were isolated from the rhizomes of Hemsleya chinensis. By detailed analysis of the NMR spectra and chemical methods, the structures of new compounds were determined to be 3-O-β-l-arabinopyranosyl-(1 → 3)-O-(6′-methyl ester)-β-d-glucuropyranosyl-oleanolic acid-28-O-β-d-glucopyranosyl-(1 → 6)-O-β-d-glucopyranoside (1), 3-O-β-l-arabinopyranosyl-(1 → 3)-O-(6′-methyl ester)-β-d-glucuropyranosyl-oleanolic acid-28-O-β-d-xylopyranosyl-(1 → 6)-O-β-d-glucopy-ranoside (2), and 13ϵ-hydroxylabda-8(17), 14-dien-18-oic acid-18-O-α-l-rhamnopyranosyl-(1 → 2)-O-β-d-glucopyranosyl-(1 → 4)-O-α-l-rhamnopyranoside (3). Diterpenoid-type compound (3) was isolated from Hemsleya genus for the first time.     

Halogenated diterpenoids from the red alga Laurencia nipponica

Chemical compositions of three collections of the red alga Laurencia nipponica from the western part of the Sea of Japan were studied. One of them contained a series of the previously known sesquiterpenoids. Another one gave C15 bromoallene ethers, predominantly. Finally, two new halogenated diterpenes, 15-bromoparguer-9(11)-ene-16-ol and 15-bromoparguer-7-ene-16-ol, were isolated from the third collection of the same species. Structures of these diterpenoids were established by 1D and 2D NMR (1H-1H COSY, DEPT, HMQC, HMBC and NOESY) along with molecular calculations for conformations having lowest energies and mass spectroscopy. Diversity and variability of halogenated secondary metabolites in L. nipponica were discussed.