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排序方式: 共有166条查询结果,搜索用时 15 毫秒
31.
Four new lupane triterpenoid saponins, along with one known lupane and eight hederagenin saponins, were isolated from the EtOH extract of the buds of Lonicera similis Hemsl. The structures of the new compounds were established as 3-O-β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl 23-hydroxybetulinic acid 28-O-β-D-glucopyranosyl ester (lonisimilioside A, 1), 3-O-β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl 23-hydroxybetulinic acid 28-O-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl ester (lonisimilioside B, 2), 3-O-β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl betulinic acid 28-O-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl ester (lonisimilioside C, 3) and 3-O-β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl betulinic acid 28-O-β-D-glucopyranosyl ester (lonisimilioside D, 4), respectively. The cytotoxic activities of the isolates against human cancer cell lines HepG2, MCF-7 and A-549 were evaluated. Only the monodesmosidic saponin with a free carboxyl group at C-28 (12) exhibited significant cytotoxicities against HepG2, MCF-7 and A-549 cell lines with the IC50 values of 8.98 ± 0.19, 12.48 ± 0.45 and 11.62 ± 0.54 μM, respectively. Furthermore, Hoechst fluorescence 33342 staining was used to demonstrate that 12 could induce HepG2 and A-549 cells apoptosis significantly. 相似文献
32.
A. S. Antonov A. I. Kalinovskii V. A. Stonik E. V. Evtushenko G. B. Elyakov 《Russian Chemical Bulletin》1994,43(7):1265-1269
A new triterpenoid glycoside, (20S,22S,23R,24S)-3,22,23-trihydroxy-3-O-[O-(-D-glucuronopyranosyl)-(16)-(-D-glucopyranosyl)]-14-nor-24-methyllanost-8(9)-en-31-oic acid (ulososide A), has been isolated from the sponge Ulosa sp. and characterized.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1326–1329, July, 1994. 相似文献
33.
A New Triterpenoid from Doellingeria scaber 总被引:1,自引:0,他引:1
SuPingBAI LiDONG ZhiAnHE LiYANG 《中国化学快报》2004,15(11):1303-1305
A new oleanane-type triterpene was isolated from the roots ofDoellingeria scaber. Itsstructure was identified as 3-oxo-16ct-hydroxy-olean-12-en-28-oic acid based on 1D and 2D NMRspectroscopy and X-ray analysis. 相似文献
34.
Guang-Ying Chen Bin Zhang Ting Zhao Najat Nidhal Wang Jia-Li Xue-Ming Zhou 《Natural product research》2020,34(13):1874-1878
AbstractA new triterpenoid glucoside, leuctriterpencoside (1), along with two known compounds (2–3) were isolated from Leucas zeylanica. The structure of the new compound was elucidated using comprehensive spectroscopic methods. Compound 1 showed significant inhibitory activity against α-glucosidase (IC50 value of 0.85?±?0.12?μM). 相似文献
35.
YueWeiGUO ZhiYuSHAO DaYuanZHU 《中国化学快报》2002,13(12):1181-1184
Two new triterpene esters,2-O-eaffeoylalphitolic acid(1)and methyl 2-O-eaffeoyl-alphitolate(2),together with two known triterpenes were isolated from the shrub Daphniphyllum oldnami.The structures of new compounds were elucidated on the basis of detailed spectroscopic analysis and compared with related compound. 相似文献
36.
A New Cyclic Bisdesmoside from Tubers of Bolbostemma paniculatum 总被引:2,自引:0,他引:2
HaiFengTANG YangHuaYI ShuYuZHANG PengSUN LingLI DaZhengZHOU 《中国化学快报》2005,16(4):479-482
The structure of tubeimoside V (1), a new cyclic bisdesmoside, isolated from tubers of Bolbostemma paniculatum (Tu Bei Mu), was established by means of 2D NMR spectral and chemical methods. Compound 1 has inter-saccharide chain bridging by a dicrotalic acid to form aunique macrocyclic structure. 相似文献
37.
《Journal of separation science》2017,40(6):1283-1292
Ultra high performance liquid chromatography coupled with mass spectrometry and combining a tissue‐smashing extraction technique was developed for the simultaneous quantitative analysis of 12 compounds in the roots of Pulsatilla chinensis . Among them, compound 6 was characterized and accurately quantified in this herb for the first time. The parameters of extraction condition were simultaneously optimized with a Box–Behnken design and Derringer's function. The optimized conditions were as follows: sample quantity of 0.5 g, ethanol concentration of 70%, and extraction time of 200 s. Multiple‐reaction monitoring scanning was employed for the quantification between positive and negative mode in a single run of 6 min. Full validation of the method was carried out, and the results indicated that the method was rapid, specific, and reliable. The developed method was successfully applied to quantify the 12 compounds in 33 batches of P. chinensis from different provinces. Moreover, the principal component analysis was performed to compare the P. chinensis collected from different provinces of China based on quantitative data and the results indicated that the content of compounds could be used to differentiate the origins of P. chinensis . These results demonstrated that this method is feasible and reliable for the quality control of P. chinensis . 相似文献
38.
From the methanolic extract of Azadirachta indica leaves, we have isolated three new tetracyclic triterpenoids of biogenetic interest, namely, melianol 1, desfurano-desacetylnimbin-17-one 2 and meliatetraone 3. The structure elucidation is based on extensive spectral studies including 1H–1H-COSY, NOESY, HMQC, and HMBC experiments. 相似文献
39.
Simone Veronique Fannang Victor Kuete Celine Mbazoa Djama Marlise Diane J.Dongfack Jean Duplex Wansi Francois Tillequin Elisabeth Seguin Elizabeth Chosson Jean Wandji 《中国化学快报》2011,22(2):171-174
A new friedelane-type triterpene named 3β-hydroxyfriedelane-7,12,22-trione,as well as nine known compounds were isolated from the whole stems of Drypetes laciniata Hutch.(Euphorbiaceae).Their structures were established on the basis of spectroscopic methods.The new triterpene derivative and a known saponin were tested for antimicrobial and antifungal activities and they appeared to be moderate active. 相似文献
40.
Inthecourseofourstudiesonnewbiologicallyactivesaponinsofnaturalmedicines,wehaveisolatedescinsla.fo.IVa.IVb,IVc,andIVdtyolnseedsof.4e'v"11/llSchinensisBee.(Hippocastanaceae),andsinglecrystalX-raydiffractionanalysiswasundertakenonescinla'.whichconfirmstheabsoluteconfigurationandsugarsequence.ThepresentpaperdescribesthestructuredeterminationofanewtriterpenoidsaponinnamedescinIVefromthesameplant.EscinIVe,whitepowder.Positive-modeTOF-MScm/zI111[M Na] ,coupledwitllNMRdata.correspondstoane… 相似文献