Chemical constituents of sponge Pseudoceratina sp. and their chemotaxonomic significance

The chemical investigation of Pseudoceratina sp. led to the isolation of six compounds including tyrosine brominated isoxazoline alkaloids (1 and 2), polyketide (3), and 5α,8α-epidioxysterols (4–6). The structures of these compounds were identified by comparison of NMR and MS spectroscopic data with those previously reported. Compounds 3–6 were isolated for the first time from sponges of the genus Pseudoceratina. The chemotaxonomic significance of these compounds was discussed.     

Studies on the Sesquiterpene Alkaloids of Tripterygium wilfordii Hook.

This paper reports two sesquiterpene alkaloids isolated from Tripterygium wilfordii Hook. f. Their structures are assigned as Ⅰ and Ⅱ, respectively, by MS, UV, IR, 1HNMR and 13CNMR spectroscopic analysis. Alkaloid Ⅱ is a new alkaloid named wilfornine. These al- kaloids were shown to be immunosuppressives.     

The pterocellins,bioactive alkaloids from the marine bryozoan <Emphasis Type="Italic">Pterocella vesiculosa</Emphasis>

Although comparatively little research has been undertaken into the secondary metabolites of bryozoans as compared with those of other marine invertebrates, bryozoans have proven to be an excellent source of novel and/or biologically active compounds. The majority of bryozoan metabolites isolated to date have been alkaloids. In our continuing search for bioactive and/or novel compounds from New Zealand marine bryozoans, we undertook an investigation of an extract of Pterocella vesiculosa (order Cheilostomatida, suborder Ascophorina, family Catenicellidae) which possessed activity against P388 murine leukaemia cells. Two alkaloids, pterocellins A–B (1–2) have been isolated from the bryozoan. The biological activity of these alkaloids was examined including their activities in the in vitro 60 cell line panel and in vivo hollow fibre assays at the National Cancer Institute (NCI). The isolation and characterisation of further pterocellin analogues is currently in progress and tentative structures for two new members of this series, pterocellins C–D (3–4) are proposed, based on NMR and mass spectral data.     

Bioactive steroidal alkaloid glycosides from Solanum aculeastrum.

Solanum aculeastrum Dunal was investigated for the presence of molluscicidal compounds. This led to the isolation of solaculine A, from the root bark in addition to known steroidal alkaloids; solamargine and beta-solamarine from the berries. The structures were elucidated by spectroscopic techniques. Molluscicidal activity of the aqueous extracts of the berries and root bark, and the isolated compounds were investigated.     

太白米中的甾体生物碱苷

对太白米的叶、大鳞茎和小鳞茎进行了化学成分系统预试,从大鳞茎中分离得到4个甾体生物碱苷,通过对其IR、FABMS、SIMS、1^HNMR、13^CNMR、DEPT、HMQC、HMBC和1^H-1^H COSY的综合解析鉴定了其中3个结构,它们分别为茄次碱-3-O-α-L-吡喃鼠李糖-(1→2)-β-D-吡喃葡萄糖苷(Ⅱ)、茄次碱-3-O-α-L-吡喃鼠李糖-(1→2)-[β-D-吡喃葡萄糖(1→4)]-β-D-吡喃葡萄糖苷(Ⅲ)和茄次碱-3-O-α-L-吡喃鼠李糖-(1→2)-[β-D-吡喃葡萄糖-(1→3)-β-D-吡喃葡萄糖(1→4)]-β-D-吡喃葡萄糖苷(IV)。     

Fate of cocaine in the lymantriid Eloria noyesi, a predator of Erythroxylum coca

Larvae of the lymantriid moth Eloria noyesi, which are obligate feeders on Erythroxylum coca, excrete most of the ingested cocaine as unchanged base. Cocaine, analysed by mass fragmentography, is readily, detectable in the blood of larvae and is presumably sequestered during larval feeding, since it is present in the bodies of adult moths that do not feed on E. coca. Cocaine is an effective feeding deterrent for the ant Monomorium pharaonis when present at a concentration below that found in the leaves of E. coca.     

Calystegines in wild and cultivated Erythroxylum species

Calystegines were identified in the genus Erythroxylum for the first time. Erythroxylum novogranatense var. novogranatense, a species cultivated for cocaine production, contained 0.2% total calystegines in dry leaves. Forty six Erythroxylum herbarium species consisting mostly of leaf tissue were analysed for calystegines, and 38 were found positive. Calystegines were compared qualitatively and quantitatively between individual Erythroxylum species. Calystegines A(3) and B(2) were the major calystegines in most species. Total calystegine content reached up to 0.32% dry mass. The simultaneous occurrence of calystegines, cocaine, other alkaloids of a 3alpha-hydroxy- or 3beta-hydroxytropane structure together with nicotine supports the concept of common biosynthetic steps of these alkaloids in Erythroxylum. The present results are the basis for further investigations of the phylogenetic origin of tropane alkaloid biosynthesis in the taxonomically remote families Solanaceae and Erythroxylaceae.     

应用HPLC图谱进行石蒜属种间关系与分类研究

利用高效液相色谱(HPLC)对石蒜属及其近缘植物中国水仙共17份样品的生物碱进行检测,以各样品生物碱色谱峰的相对保留时间为变量,采用SPSS12.0中的Q型聚类法,得到树形图。聚类分析结果显示,17份样品聚成3类:第Ⅰ类包括长筒石蒜、安徽石蒜、鹿葱、换锦花、中国石蒜、香石蒜、乳白石蒜、红蓝石蒜8个种;第Ⅱ类由石蒜、稻草石蒜、江苏石蒜、忽地笑、玫瑰石蒜、矮小石蒜组成;中国水仙单独成第Ⅲ类。聚类结果与传统分类结果有较好的一致性,并支持鹿葱、玫瑰石蒜、安徽石蒜杂交起源的观点。外形相似的忽地笑与中国石蒜,矮小石蒜与石蒜HPLC图谱明显有别,表现出较远化学亲缘关系。表明HPLC化学图谱可用于石蒜属及其近缘植物中国水仙的分类和鉴别研究,并为石蒜属植物指纹图谱研究和质量控制提供重要参考。