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A method for preparative production of 3β,20S-dihydroxydammar-24-en-12-one 3,20-di-O-β-D-glucopyranoside (1), a glycoside from Panax japonicus, chikusetsusaponin-LT8 was developed. Chemical transformation of betulafolientriol, a component of Betula leaves extract, produced the 12-keto-20S-protopanaxadiol (3β,20S-dihydroxydammar-24-en-12-one) (2), exhaustive glycosylation of which by 2,3,4,6-tetra-O-acetyl-α-D-glucopyranosylbromide (3) under Koenigs—Knorr reaction conditions with subsequent removal of protecting groups formed 3β,20S-dihydroxydammar-24-en-12-one 3,20-di-O-β-D-glucopyranoside (1). The principal glycosylation product was 3β,20S-dihydroxydammar-24-en-12-one 3-O-β-D-glucopyranoside if equimolar amounts of (2) and (3) were used. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 44–48, January–February, 2006.  相似文献   
2.
本文将迄今为止国内外文献报道的200余种达玛烷型皂甙类化合物的~(13)C化学位移按其结构特征分类整理,以原人参二(三)醇等为模型化合物,讨论了皂甙元结构变化引起的位移变化(Δδ_C)规律。  相似文献   
3.
Abstract

Gypensapogenin H (Gyp H) is a novel dammarane-type triterpene, isolated from hydrolyzate of total saponins from Gynostemma pentaphyllum. Our previous work demonstrated that Gyp H exhibited potent growth inhibitory effects on tumor cells. It significantly inhibited the growth of human breast cancer cells (MDA-MB-231), while having low toxicity to normal human breast epithelial cells, MCF-10a. Further mechanistic study demonstrated that Gyp H decreased survival, inhibited proliferation, migration, induced apoptosis and led to cell cycle arrest. For the MDA-MB-231 cell lines, Gyp H increased expression of P21, Bax and cytochrome c, induced PARP cleavage and activated caspases. Gyp H also reduced expression of CDK2/4, CyclinD1, E2F1 and Bcl2, which associated with the cell cycle arrest. Thus, our finding may be useful for understanding the mechanism of action of Gyp H on breast cancer cells and suggest that Gyp H would be a leading agent for the treatment of breast cancer.  相似文献   
4.
In our continuing research works on Panax notoginseng (Burk.) F. H. Chen, a famous traditional Chinese herb medicine1, two new dammarane glycosides named notoginsenosides T1 (1) and T2 (2) were isolated from the mild acid hydrolysis products of the root saponins. We report herein the structure elucidation of these two novel glycosides.Notoginsenosides T1(1) was obtained as white solid, [(] = +14.49 (0.50, MeOH). Its negative mode HR-FAB-MS spectrum showing the quasimolecular ion peak a…  相似文献   
5.
Pistacia species contain oleoresins with bioactive triterpenes. In this study triterpenes, including minor components, were identified and quantified in both neutral and acidic fractions of Pistacia terebinthus var. Chia resin, grown exclusively in Chios island (Greece), collected traditionally, as well as using stimulating agents (liquid collection). It was proved that these two resin samples were composed of several different minor triterpenes, while major constituents were similar but in different proportions. Compounds that differentiated two resin samples of P. lentiscus and P. terebinthus var. Chia, both traditionally collected, were detected, in order to identify the nature of resins present in archaeological materials. In the traditionally collected resin, 37 triterpenes were identified, 12 in the acidic and 25 in the neutral fraction. In the liquid collection resin 10 compounds were identified in the acidic and 23 in the neutral fraction, while 16 compounds were not contained in the traditionally collected resin. The main triterpenes in both resin samples collected traditionally and using stimulating agents were: isomasticadienonic acid (23.6 and 26.3% w[sol ]w of the triterpenic fraction, respectively), 28-norolean-17-en-3-one (16.3 and 17.5% w[sol ]w of the triterpenic fraction, respectively) and masticadienonic acid (5.8 and 6.0% w[sol ]w of the triterpenic fraction). In this study the qualitative and quantitative composition of triterpenes was compared in the Pistacia lentiscus and P. terebinthus var. Chia resin samples collected with the traditional and new liquid techniques, and also triterpenes in resins of P. terebinthus obtained by the traditional technique and using stimulating agents. The aim of the study was also to examine whether the collection technique influenced the triterpenes contained in P. terebinthus var. Chia resin samples.  相似文献   
6.
A preparative semi-synthetic method was developed to prepare 20S-protopanaxadiol 20-O-β-Dglucopyranoside (1), a metabolite of Panax ginseng glycosides. The 20-O-•-D-glucopyranosides of 20S-hydroxydammar-24-en-3,12-dione, 3β,20S-dihydroxydammar-24-en-12-one, and 3β,12α, 20S-trihydroxydammar-24-ene were synthesized for the first time. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 364–369, July–August, 2006.  相似文献   
7.
8.
Two new esters of dammarane triterpenoids ixorene isovalerate (1), ixorene 3′,8′-dimethyloctanoate (2) and a new ursane-type triterpenoids Ixoroid acid (3) were isolated from the methanolic extract of flowers of Ixora coccinea Linn., along with the three known constituents. The structures of compounds 1 and 3 were elucidated on the basis of extensive 1D,2D NMR studies and mass spectrometry as 17β-dammara-12,20-diene-3β-isovelarate and 3β-hydroxy-18β-urs-12ene-29β-oic acid, respectively, whereas 2 was identified as 17β-dammara-12,20-diene-3β-3′,8′-dimethyloctanoate through 1H NMR and mass spectral data. Compounds 1, 2, 4 and 5 were evaluated for their in vitro cytotoxic activity, which exhibited weak activity against the 3T3, PC3 and HeLa cell lines with the IC50 value >30 μM. Antioxidant results of 1 – 5 revealed that only compound 5 showed antioxidant activity in DPPH radical scavenging inhibition with the IC50 1.31 × 10? 6 ± 0.005 μm mL? 1. Both activities are the first records of these isolated compounds from the flowers of Ixora coccinea Linn.  相似文献   
9.
Pistacia species contain oleoresins with bioactive triterpenes. In this study triterpenes, including minor components, were identified and quantified in both neutral and acidic fraction of Pistacia lentiscus var. Chia resin, grown exclusively in Chios island (Greece), collected traditionally, as well as by the use of stimulating agents (liquid collection). It was proved that these two resin samples were composed of several different minor triterpenes. In the traditional collection of the resin, 36 triterpenes were identified, 23 of which are new minor compounds (five in the acidic and eighteen in the neutral fraction). In the liquid collection resin eight compounds were identified in the acidic and 11 in the neutral fraction, while seven compounds were not contained in resin traditionally collected. The main triterpenes in both resin samples collected traditionally and by use of stimulating agents were in the following order: isomasticadienonic acid (24 and 22.5% w/w of triterpenic fraction respectively), masticadienonic acid (9.3 and 14.7% w/w of triterpenic fraction) and 28-norolean-17-en-3-one (19 and 36% w/w of triterpenic fraction respectively). The aim of this study was to compare the qualitative and quantitative composition of triterpenes in the resin samples collected using the traditional and new liquid techniques, and examine whether the collection technique influences the contained triterpenes in P. lentiscus var. Chia resin samples. Finally, since there is confusion on interpreting mass spectra of triterpenes we present an analytical review on the base peaks, main fragments and fragmentation mechanism/pattern of several skeleton penta- and tetra- cyclic triterpenes reported in P. lentiscus resin. Also, a biosynthetic route for triterpene skeletons contained in P. lentiscus resin was approached.  相似文献   
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