Semisynthesis of triptolide analogues: Effect of B-ring substituents on cytotoxic activities

A series of B-ring modified analogues of triptolide were synthesized and tested for their cytotoxicity against two human tumor cell lines (U251 and PC-3). From the current investigation, the structure–cytotoxic activity relationships of these analogues suggested that the introduction of hydroxyl, epoxide, halogen or olefinic groups on C5 and/or C6 could still retain the cytotoxicity, albeit a little less potency, and the C7,C8-β-epoxide group of triptolide was essential to its potent cytotoxic activity.     

Cytotoxic diterpenoid quinonemethides from the roots of Pygmacopremna herbacea

Two new diterpenoid quinonemethides (1 and 2) along with two known compounds (3 and 4) were isolated from the hexane and ethyl acetate extracts of root nodules of Pygmacopremna herbacea. The structures of the new compounds were established by spectroscopic data interpretation. Single crystal X-ray diffraction analysis confirmed the structure of 1. The cytotoxic activities of these compounds were evaluated against A 549, HEPG2, MCF-7, PC-3 and HELA cancer cell lines. Compounds 4, 2 and 1 were shown very good cytotoxic activity.     

Structures of the novel diterpene glycosides from Stevia rebaudiana

From the commercial extract of the leaves of Stevia rebaudiana, two new diterpenoid glycosides were isolated besides the known steviol glycosides including stevioside, rebaudiosides A–F, rubusoside, and dulcoside A. The structures of the two new compounds were identified as 13-[(2-O-6-deoxy-β-d-glucopyranosyl-β-d-glucopyranosyl)oxy] ent-kaur-16-en-19-oic acid β-d-glucopyranosyl ester (1), and 13-[(2-O-6-deoxy-β-d-glucopyranosyl-3-O-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.     

Terpenoids from Juniperus polycarpus var. seravschanica

Two eudesmanes, two abietanes, two podocarpanes and other nine known compounds were isolated from the dried fruits of Juniperus polycarpus var. seravschanica. Their structures were established on the basis of analysis of spectroscopic evidence. Some of the isolated terpenoids showed antimalarial activity.     

近无毛灰岩香茶菜的研究

从云南省会泽县产近无毛灰岩香茶莱〔Rabdosia calcicola (Hand. -Mazz.) Hara var. subculva (Hand. -Mazz.) C. Y. Wu et H. W. Li〕叶中分得两个二萜化合物,一个为新化合物,命名为灰岩香茶菜甲素(calcieolin A),另一个为已知化合物维西香茶菜甲素(weisiensin A),经各项光谱数据和化学反应确定,灰岩香茶菜甲素为3β-羟基-1α,6α,7β,11β-四乙酰氧基-对映-贝壳杉-16-烯-15-酮(1);维西香茶菜甲素结构应为3β,6α-二羟基-1α,7β,11β-三乙酰氧基-对映—贝壳杉-16-烯-15酮(2)。     

瓜叶乌头的二萜生物碱

从瓜叶乌头（ＡｃｏｎｉｔｕｍｈｅｍｓｌｅｙａｎｕｍＰｒｉｔｚ．）的块根分离到４个二萜生物碱,通过波谱分析和化学方法分别鉴定为８－ａｃｅｔｙｌ－１４－ｂｅｎｚｏｙｌ－ｅｚｏｃｈａｓｍａｎｉｎｅ（１）、ｃｈａｓｍａｎｉｎｅ（２）、ｉｎｄａｃｏｎｉｔｉｎｅ（３）和ｔａｌａｔｉｓａｍｉｎｅ（４）。其中１为新化合物,命名为瓜叶乌宁（ｈｅｍｓｌｅｙａｎｉｎｅ）。瓜叶乌宁（１）为白色块状结晶,ｍｐ１１５—１１６℃,［α］２０Ｄ＋１９．０２°。由ＦＡＢ－ＭＳ和ＥＩ－ＭＳ得知,分子量为６１３,１３Ｃ－ＮＭＲ中３２…     

Diterpenoids from Jatropha multifida

Chemical investigation on the stems of Jatropha multifida yielded two diterpenoids, multifolone and (4E)-jatrogrossidentadione acetate along with five known diterpenoids, a flavone and a coumarino-lignan. The structures of the compounds were settled by detailed analysis of their 1D and 2D NMR spectra. The X-ray crystallographic analysis of (4E)-jatrogrossidentadione acetate was also accomplished.     

急尖绣线菊中一微量新二萜生物碱

从蔷薇科绣线菊属植物急尖绣线菊（Ｓｐｉｒａｅａ ｊａｐｏｎｉｃａ ｖａｒ．ａｃｕｔａ Ｙｕ）的根部分离得到６个二萜生物碱,经光谱分析,其中５个来ｓｐｉｒａｍｉｎｅｓ Ａ（１）,Ｂ（２）,Ｐ（３）和Ｕ（４）及ｓｐｉｒａｄｉｎｅ Ｆ（５）,另一微量成分被鉴定为一新的二萜生物碱,命名为ｓｐｉｒａｍｉｎｅ Ｗ（６）。     

Diterpenoids from Pinus massoniana resin and their cytotoxicity against A431 and A549 cells

Five diterpenoids and 14 known diterpenoids were isolated from the petroleum ether extract of Pinus massoniana resin. Their structures were elucidated by spectroscopic data interpretation. The cytotoxic activities of these compounds were evaluated using the MTT method. The results showed that three of the less polar diterpenoids had strong cytotoxicity against A431 and A549 cancer cells, whereas those of high polarity had none.     

ent-Verticillane-type diterpenoids from the Japanese liverwort Jackiella javanica

Three ent-verticillane diterpenoids and two ent-sesquiterpenoids were isolated from the Japanese liverwort Jackiella javanica Schiffn. together with five known ent-verticillane and three ent-kaurane diterpenoids, and three sesquiterpenoids. Five ent-verticillane epoxides were synthetically prepared from ent-verticillols action to clarify the absolute configuration of natural ent-9,10-epoxyverticillol. Their structures were established by extensive NMR spectroscopic and X-ray crystallographic analyses.