Alkaloidal oviposition stimulants for a danaid butterfly,Ideopsis similis L., from a host plant,Tylophora tanakae (Asclepiadaceae)

Chemicals releasing oviposition by an Asclepiadaceae feeder,Ideopsis similis, were identified from a host plant,Tylophora tanakae. A strong positive response was evoked by a methanolic extract of the plant, which proved to contain multiple stimulants. A mixture of two phenanthroindolizidine alkaloids, (+)-isotylocrebrine and (–)-7-demethyltylophorine, isolated from organic fractions, elicited significant ovipositional responses from females.     

Methyllycaconitine,a naturally occurring insecticide with a high affinity for the insect cholinergic receptor

Summary Studies of extracts ofDelphinium seeds, long known to be insecticidal, revealed that a principal insecticidal toxin was methyllycaconitine, which is shown to be a potent inhibitor of -bungarotoxin binding to housefly heads (K_inh=2.5×10^–10±0.5×10^–10M).Calgary for gifts of MLA, citrate and lycoctonine, and Dr W. Bowers of the University of Arizona for the original extract ofDelphinium seeds. We would also like to acknowledge the able technical support of Ms C. Dushin, Mr E.L. Bowman, Dr C. C. Gagne, Mr R. F. Borysewicz and Dr P. Mowery for his assistance in obtaining and interpreting the carbon-13 NMR spectra.     

The biologically active conformation of ergot alkaloids

Summary Molecular mechanics and NMR studies of the D ring conformation of ergot alkaloids demonstrate that both D₁ and D₂ forms may exist in solution. The comparison of the geometric parameters defining the spatial relations between the aromatic moieties and the basic nitrogen of conformationally restricted dopamine analogs, and that of ergolene, shows the D₁ conformation to be the bioactive one.     

紫毛香茶菜二萜成分研究

从紫毛香茶菜干叶的乙醇提取物中分离得到２个二萜化合物,利用红外、紫外、质谱以及核磁共振波谱等光谱方法,对这２个化合物的结构进行了鉴定．紫毛香茶菜的化学成分尚未见文献报道．     

Elicitor对长春花冠瘿细胞次级代谢的影响

比较六种不同来源的ｅｌｉｃｉｔｏｒ（激发子）对培养１５天的长春花冠瘿细胞次级代谢的刺激效果，发现它们均程度不同的促进了冠瘿细胞总吲哚生物碱的积累。其中在１００ｍｌ细胞培养液中加入５ｍｌ大丽花轮枝孢制备的ｅｌｉｃｉｔｏｒ刺激效果最佳。     

具有抗肿瘤活性的生物碱类化合物

从各种生物中寻找天然抗肿瘤活性物质是抗癌药研究的一个重要途径，生物碱类在已分离的各类天然抗肿瘤活性物质中占有较大比重，其中有些已经用于临床并取得了较好的抗肿瘤作用，在已知的生物碱中，来源于芸香料植物山油柑心材和根部的降真香碱可能是最广谱的抗肿瘤活性物质，而从印度洋海蠕虫中提取的几种双甾体生物碱的抗肿瘤活性最强，对Ｐ３８８细胞（ＰＳ体系）的ＥＤ５０为１０＾－６－１０＾－４μｇ．Ｌ＾－１。     

岷江柏的化学成分研究(二)

目的:研究岷江柏的化学成分.方法:反复运用正相硅胶、Sephadex LH-20柱色谱分离提纯,经理化常数测定,结合IR、ESI-MS、1H-NMR、13C-NMR等现代波谱学技术确定化合物结构.结果:从岷江柏乙醇提取物中分离纯化出7个化合物,分别鉴定为β-胡萝卜苷(β-daucosteol)1,槲皮苷(quercitrin)2,木犀草素(luteolin)3,柏黄酮(cupressuflavone)4,穗花杉双黄酮(amentoflavone)5,新柳杉双黄酮(neocryptomerin)6,7-甲氧基香豆素(hemiarin)7.结论:化合物1-7为首次从该植物中分离得到.     

北豆根总碱粉针剂中蝙蝠葛碱质量分数稳定性

采用反相高效液相色谱法对北豆根总碱粉针剂中蝙蝠葛碱质量分数进行了3个月的初步稳定性考察.结果表明,0～3个月内3批北豆根总碱粉针蝙蝠葛碱质量分数在69.63%～73.17%之间变化,稳定性较好,符合新药稳定性要求.     

钩吻吲哚生物碱类化合物研究进展

目的：综述马钱科胡蔓藤属钩吻植物化学成分及药理作用的研究进展。方法：检索有关文献进行综合分析。结果：钩吻主要的化学成分为吲哚生物碱类化合物,其中某些成分有显著毒理、抗肿瘤、免疫调节作用。结论：钩吻的化学成分主要是生物碱类,药理活性显著,具有进一步开发利用的前景。