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排序方式: 共有261条查询结果,搜索用时 15 毫秒
241.
Toshio Morikawa Hisashi Matsuda Ning Li Xian Li Masayuki Yoshikawa 《Helvetica chimica acta》2007,90(12):2342-2348
Three new acylated oleanane‐type triterpene saponins, theasaponins A6 ( 1 ), A7 ( 2 ), and B5 ( 3 ), were isolated from the saponin fraction of the seeds of the Japanese tea plant Camellia sinensis together with the known constituent foliatheasaponin III ( 4 ). The structures of the glycosides 1 – 3 were elucidated on the basis of spectroscopic, chemical, and physico‐chemical evidence. 相似文献
242.
Lunli Xiang Lu Zhang Xuanqin Chen Xueshan Xia Rongtao Li 《Natural product research》2019,33(9):1349-1356
Investigation of the n-BuOH extract of the aerial parts of Elsholtzia bodinieri led to the isolation of two new ursane-type triterpenoid saponins, bodiniosides O (1) and P (2), along with five known saponins, rotungenoside (3), 3,28-O-bis-β-d-glucopyranosides of 19α-hydroxyarjunolic acid (4), oblonganosides I (5), rotungenic acid 28-O-α-L-rhamnopyranosyl-(1→2)-β-d-glucopyranoside (6), and bodinioside M (7) isolated from the species. The structures of compounds 1 and 2 were characterized by spectroscopic data as well as acid hydrolysis and GC analysis as 3-O-β-d-xylopyranosyl-23-acetoxy-urs-12(13)-en-28-oic acid 28-O-β-d-xylopyranosyl-(1→6)-[β-d-glucopyranosyl-(1→4)-α-L-rhamnopyranosyl-(1→2)]-β-d-glucopyranoside and 3-O-β-d-xylopyranosyl-23-hydroxy-urs-12(13)-en-28-oic acid 28-O-β-d-glucopyranosyl-(1→6)-β-d-glucopyranoside. Compounds 1 and 2 exhibited potent anti-HCV activities in vitro with a selective index of 30.63 and 9.08, respectively. 相似文献
243.
Yun Ling Qing Zhang Wenjuan Zhong Mengping Chen Haonan Gong Shasha He 《Natural product research》2020,34(15):2144-2150
AbstractIn the present work, high performance liquid chromatography coupled to electrospray ionization and quadrupole time-of-flight mass spectrometry (HPLC-ESI-QTOF-MS/MS) has been used for the identification of the major chemical constituents from the fruits of Sapindus mukorossi. A total of 31 peaks were identified based on their accurate masses and fragmentation characteristics. Among these 9 acyclic sesquiterpene oligoglycosides and 8 triterpenoid saponins were reported from the fruits of Sapindus mukorossi for the first time. This study demonstrates the potential of HPLC-ESI-QTOF-MS/MS for analysis and identification of acyclic sesquiterpene oligoglycosides and triterpenoid saponins. 相似文献
244.
245.
建立了同时测定洋常春藤中绿原酸、隐绿原酸、芦丁、烟花苷、常春藤皂苷C、常春藤皂苷D、常春藤皂苷B和α-常春藤皂苷8种成分的超高效液相色谱法(UHPLC)。以80%甲醇为溶剂,将药材粉末于85℃、料液比1∶100条件下水浴回流1 h,制备供试品溶液;采用Agilent ZORBAX Eclipse Plus-C_(18)(2.1 mm×100 mm,1.8μm)色谱柱,以乙腈-0.05%磷酸溶液为流动相进行梯度洗脱。结果表明,上述8种成分均获得良好的分离度;仪器精密度、方法重复性的相对标准偏差(RSD)均小于3.0%;样品溶液在室温条件下24 h内稳定;8种成分在对应质量浓度范围内线性关系良好(r≥0.999 5),检出限为0.40~10.58μg·mL~(-1),定量下限为1.31~34.61μg·mL~(-1),平均回收率为97.3%~108%,RSD(n=6)为0.51%~3.2%。该方法适用于洋常春藤中上述8种化学成分的定量分析。 相似文献
246.
应用1H NMR、13C NMR、HSQC、HMBC等多种NMR实验测试方法,结合MS技术,确认了2个半合成偏诺皂苷的结构,即:偏诺皂苷元-3-O-α-L-鼠李吡喃糖基(1→2)-α-D-葡萄吡喃糖苷(1),偏诺皂苷元-3-O-{α-L-鼠李吡喃糖基(1→2)-[α-L-鼠李吡喃糖基(1→4)]}-α-D-葡萄吡喃糖苷(2),并对这2个化合物的1D NMR谱数据进行了全归属. 这2个化合物目前没有天然产物的报道. 通过药理实验发现,这2个连接α-D葡萄糖的偏诺皂苷则没有缩宫止血活性,表明该类化合物3位糖苷键的构型决定其是否具有生物活性. 相似文献
247.
高效液相色谱-串联质谱法同时测定辽东楤木不同部位中5种皂苷类成分的含量 总被引:1,自引:0,他引:1
建立了高效液相色谱-串联质谱法(HPLC-MS/MS)用于测定辽东楤木不同部位中的楤木皂苷Ⅱ、楤木皂苷Ⅳ、楤木皂苷Ⅴ、楤木皂苷Ⅹ和楤木叶皂苷Ⅱ的含量,并比较了楤木不同部位中上述5种皂苷的含量差异。以Alltima C18柱(250 mm×4.6 mm,5 μm)为分析柱,以乙腈和0.1%(体积分数)甲酸水溶液为流动相,梯度洗脱,流速为0.8 mL/min。在电喷雾正离子多反应监测(MRM)模式下进行检测。结果表明该方法中楤木皂苷Ⅱ、楤木皂苷Ⅳ、楤木皂苷Ⅴ、楤木皂苷Ⅹ和楤木叶皂苷Ⅱ分别在0.17~108 μg/L、0.53~329 μg/L、0.77~480 μg/L、0.77~480 μg/L和0.82~510 μg/L范围内线性关系良好,相关系数(r2)均大于0.999,提取回收率为99.0%~100.2%。该方法简单、快速、灵敏,可用于测定辽东楤木药材不同部位中的皂苷类成分的含量。测定结果发现楤木不同部位中上述5种皂苷总量多少的顺序为根皮 >叶 >种子 >芽。 相似文献
248.
TIAN Weisheng XU Qihai CHEN Ling & ZHAO Chunfeng Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai China 《中国科学B辑(英文版)》2004,47(2):142-144
Pennogenin (1) is an aglycone of bioactive com-ponents of Chinese traditional medicine named Chonglou(Paris),[1] which belongs to C-17-hy- droxyl-steroidal sapogenin. It is well known that Chonglou as well as the related herbs containing pennogenin and its glycosides have been used as haemostatic agents in clinic. They also exhibit antibi-otic and antitumor activity[1,2]. With the demand amount of Chonglou as well as the related drugs increasing while the plant resource decreasing day by day… 相似文献
249.
Yaomin Wang Chen Xia Lianfu Chen Yi Charlie Chen Youying Tu 《Molecules (Basel, Switzerland)》2020,25(22)
Tea flower saponins (TFS) possess effective anticancer properties. The diversity and complexity of TFS increases the difficulty of their extraction and purification from tea flowers. Here, multiple methods including solvent extraction, microporous resin separation and preparative HPLC separation were used to obtain TFS with a yield of 0.34%. Furthermore, we revealed that TFS induced autophagy—as evidenced by an increase in MDC-positive cell populations and mCherry-LC3B-labeled autolysosomes and an upregulation of LC3II protein levels. 3-MA reversed the decrease in cell viability induced by TFS, showing that TFS induced autophagic cell death. TFS-induced autophagy was not dependent on the Akt/mTOR/p70S6K signaling pathway. TFS-induced autophagy in OVCAR-3 cells was accompanied by ERK pathway activation and reactive oxygen species (ROS) generation. This paper is the first report of TFS-mediated autophagy of ovarian cancer cells. These results provide new insights for future studies of the anti-cancer effects of TFS. 相似文献
250.
Aleksandar Shkondrov Franz Bucar Olaf Kunert Magdalena Kondeva-Burdina Iliana Ionkova 《Natural product research》2020,34(4):511-517
AbstractA new tetracyclic saponin, 17(R),20(R)-3β,6α,16β-trihydroxycycloartanyl-23-carboxylic acid 16-lactone 3-O-β-D-glucopyranoside (1) together with one known flavonoid, camelliaside A (2) were isolated from the aerial parts of Astragalus glycyphyllos L. Their structures were determined by chemical, HRESIMS and NMR methods. On 6-hydroxydopamine in vitro model on isolated rat brain synaptosomes, compounds 1–2 had statistically significant neuroprotective activity similar to that of Silibinin, tested at 100?μM. Saponin 1 possessed the most prominent neuroprotective and antioxidant effects in this in vitro model. On human recombinant monoamine oxidase type B enzyme compound 1 displayed strong inhibiting activity, compared to Selegiline (1?μM). It could be concluded that the new epoxycycloartane saponin 1 could be a promising leading structure in respect of neurodegenerative diseases. 相似文献