Alkaloids of Pergularia pallida

Five phenanthroindolizidine alkaloids namely tylophorine, tylophorinidine, pergularinine, desoxypergularinine and an unidentified base (M⁺ 409) have been isolated from the roots of Pergularia pallida plants.     

13a-hydroxytylophorine from tylophora hirsuta

13a-hydroxytylophorine isolated from Tylophora hirsuta on heating with concentrated hydrochloric acid gave a quaternized salt which was reduced with sodium borohydride to (+)-tylophorine. An amine and a ketoamine having a seco[10–13a] bond were formed after lithium aluminium hydride reduction and chromium trioxide oxidation, respectively.     

卵叶娃儿藤中的抗癌活性生物碱

从卵叶娃儿藤 (Tylophoraovata (Lindl.)Hook .exSteud .)根中分离得到 4个菲骈吲哚里西丁类生物碱 ,分别为tylophoridicineA (1)、娃儿藤宁 (2 )、氧甲基娃儿藤定 (3)和娃儿藤定 (4 )。经波谱分析并结合化学方法鉴定 ,其结构分别为 :(13aR)_6_羟基_3,7_二甲氧基菲骈吲哚里西丁、(13aS ,14R)_14_羟基_3,6 ,7_三甲氧基_菲骈吲哚里西丁、(13aS ,14S)_14_羟基_3,6 ,7_三甲氧基_菲骈吲哚里西丁和 (13aS ,14S)_6 ,14_二羟基_3,7_二甲氧基_菲骈吲哚里西丁。化合物 1为新化合物 ,化合物 2 - 4为首次从该植物得到的化合物。经药理筛选 ,化合物 1、3和 4显示很强的抗癌活性。     

卵叶娃儿藤中的抗癌活性生物碱

从卵叶娃儿藤(Tylophora ovata (Lindl.) Hook. ex Steud.)根中分离得到 4个菲骈吲哚里西丁类生物碱,分别为tylophoridicine A (1)、娃儿藤宁(2)、氧甲基娃儿藤定(3)和娃儿藤定(4).经波谱分析并结合化学方法鉴定,其结构分别为:(13aR)-6-羟基-3,7-二甲氧基菲骈吲哚里西丁、 (13aS ,14R)-14-羟基-3,6,7-三甲氧基-菲骈吲哚里西丁、(13aS, 14S)-14-羟基-3,6,7-三甲氧基-菲骈吲哚里西丁和(13 aS,14S)-6,14-二羟基-3,7-二甲氧基-菲骈吲哚里西丁.化合物1为新化合物,化合物2-4为首次从该植物得到的化合物.经药理筛选,化合物1、3和4显示很强的抗癌活性.     

Incorporation of cinnamic acid-2-[14C] into tylophorine

Tylophora indica plants have been shown to contain phenanthroindolizidine alkaloids of the tylophorine type. Cinnamic acid-[2-¹⁴C]was incorporated efficiently into these alkaloids supporting the hypothesis that ring A and C-10 and C-6$\text{\$}\text{?}$of tylophorine are derived from phenylalanine.     

Tylophorinicine,a phenanthroindolizidine alkaloid from tylophora asthmatica and pergularia pallida

Tylophorinicine, a minor alkaloid isolated from the roots of Tylophora asthmatica and Pergularia pallida has been characterized as 14-hydroxytylophorine from physical and chemical evidence.     

Two carboxy- and two hydroxymethyl-substituted aristololactams from Aristolochia argentina

Four new aristololactams have been isolated from Aristolochia argentina. The evidence indicates them to be 10-amino-3-hydroxymethyl-2,4-dimethoxyphenanthrene-1-carboxylic acid lactam, 10-amino-3-hydroxymethyl-2,4,6-trimethoxyphenanthrene-1-carboxylic acid lactam, 10-amino-2-hydroxy-4-methoxyphenanthrene-1,3-dicarboxylic acid lactam and 10-amino-2-hydroxy-4,6-dimethoxyphenanthrene-1,3-dicarboxylic acid lactam.     

Oviposition-stimulatory activity of phenanthroindolizidine alkaloids of host-plant origin to a danaid butterfly, Ideopsis similis

Oviposition response of Ideopsis similis (L.) (Lepidoptera: Danaidae) was examined for 12 phenanthroindolizidine alkaloids present in its host plant, Tylophora tanakae (Maxim.) (Asclepiadaceae). At least five alkaloids, i.e. (+)‐isotylocrebrine (3,4,6,7‐tetramethoxyphenanthroindolizidine; l ), (+)‐3‐demethyliso‐ tylocrebrine ( 3 ), (+)‐isotylocrebrine N‐oxide ( 5 ), (+)‐6‐demethyltylocrebrine ( 8 ) and (–)‐7‐demethyltylophorine ( 10 ), were found to individually stimulate oviposition by females. Of these, compounds 1, 3 and 10 were regarded as key components most responsible for host recognition or preference. However, female egg‐laying was much higher in response to a mixture of the five alkaloids. In two‐choice bioassays, more eggs were deposited on samples comprising the five alkaloids than on samples consisting of a single alkaloid. This suggests strongly that host selection by the butterfly is mediated by the synergistic action of several phenanthroindolizidine alkaloids present in the host plant.     

娃儿藤属(萝藦科)植物花粉器形态

用光镜对我国萝藦科(Asclepiadaceae)娃儿藤属(Tylophora)17种植物的花粉器形态进行了观察。结果表明,着粉腺的形态有4种类型:长圆形、近方形、三角形和倒立三角形。花粉块的形态有3种类型:球形、长球形和超长球形。花粉块柄的长度、着粉腺和花粉块的形态和大小在种间存在较显著的差异,可作为区分种的辅助特征,对娃儿藤属植物的分类有较大意义。     

Ervatinine,an indole alkaloid from Ervatamia coronaria

An indole alkaloid, ervatinine, has been isolated from the leaves of Ervatamia coronaria and its structure has been elucidated.     

Alkaloids from Pelea barbigera

From the rutaceous Hawaiian shrub Pelea barbigera we have isolated the furoquinoline alkaloid kokusaginine, the 4-quinolone isoplatydesmine, and a     

Glycarpine,a new alkaloid from Glycosmis cyanocarpa

Glycarpine, a new furoquinolone alkaloid and evolitrine have been isolated from Glycosmis cyanocarpa.     

Alkaloids from Haplophyllum suaveolens

Flindersine, γ-fagarine, kokusaginine and one new alkaloid of the flindersine-type were isolated from the aerial parts of Haplophyllum suaveolens. Spectral methods were used to determine the structures of the alkaloids.     

Alkaloids from Strychnos usambarensis: Revised structure for usambarine

Synthesis has shown an error in the structural determination of usambarine. A further examination of IR and PMR spectra indicates a revised structure for this alkaloid. Stereochemistry (3S, 4R, 15S, 17S, 20R) has been advanced from the CD curve and biosynthetic considerations.