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21.
Two isomers of megastigmane glycosides, (6R, 9S)-blumenol C 9-O-gentibioside (2) and (6S, 9S)-blumenol C 9-O-gentiobioside (3), and a new 7,9′-dinorlignan glycoside, stepdonorlignoside (4) were isolated from the tubers of Stephania kaweesakii. The structure determinations were considered based on the physical data and spectroscopic evidence. The absolute configurations of two megastigmanes were determined for the first time. Additionally, ten known compounds were isolated: (6R, 9S)-blumenol C 9-O-β-D-glucopyranoside, (+)-isolariciresinol 3a-O-β-D-glucopyranoside, salidroside, N-trans-caffeoyltyramine, (R)-isococlaurine, (R)-isococlaurine 4′-O-β-glucopyranoside, (−)-oblongine, (+)-magnocurarine, fordianoside, and (−)-cyclanoline.  相似文献   
22.
山东新植物     
发表了山东产的野豌豆属一新变种,即白花长柔毛野豌豆Vicia villosaRoth var.alba Y.Q.Zhu和朴属一新变型,即垂枝朴Celtis tetrandra Roxb.f.pendulaY.Q.Zhu.  相似文献   
23.
Eight alkaloids had been isolated from the roots of Stephania rnacrantha H. S. Lo et M. Yang which is a novel species growing in Yang-bi district of Yunnan Province. The structures of these compounds were identified as l-tetrahydropalmatine ( Ⅰ ), isocorydine ( Ⅱ ), corydine ( Ⅲ ), corydalmine (Ⅳ), stepholidine ( Ⅴ ), palmatine ( Ⅵ ), corytuberine salt (Ⅶ) and laudanidine (Ⅷ) by means of spectral and chemical methods. Isocorydine is a main alkaloid with 1.82% yield. It is interested that laudanidine is found for the first time in the plants of Menispermaceae.  相似文献   
24.
Eleven alkaloids were isolated from roots of Stephania succifera Lo et Tsoong. They were identified as crebanine (Ⅰ), tetrahydropalmatine (Ⅱ), dehydrocrebanine (Ⅲ), palmatine (Ⅳ). dehydrocorydalmine (Ⅴ), crebanine nitrate (Ⅵ), oxocrebanine (Ⅶ), corydalmine (Ⅷ), phanostenine (Ⅸ), discretamine (Ⅹ) and corypalmine (Ⅺ) by means of TLC. UV, NMR MS spectral analyses and the fact that no depression of MP. with authentic samples was observed. Compounds Ⅳ, Ⅴ, Ⅵ, Ⅶ, Ⅸ, Ⅹ and Ⅺ were first reported from this plant.  相似文献   
25.
以黄根醇提物为实验药物,对其进行了最大耐受量试验(MTD)和小鼠实验性急性肝损伤的研究,结果表明黄根醇提物最大耐受量为2080g生药/kg,并能显著降低CCL4、D-GalN所致的小鼠血清中ALT、AST升高(P<0.01);亦能明显降低BCG和LPS致免疫性肝损伤小鼠血清中ALT、AST及肝组织中的MDA的水平(P<0.01),增加肝组织中SOD的活性和GSH的水平(P<0.01)。该实验属首次报道。  相似文献   
26.

Introduction

The tuberous roots of Stephania kwangsiensis, which contain bioactive alkaloids, are used as a traditional Chinese medicine. Overexploitation of the roots has made the plant increasingly rare, and the abundant leaves of the same plant may offer a potential alternative. However, there is insufficient phytochemical information for a comparison of alkaloid compositions in the two parts.

Objective

To characterise and compare the alkaloids in the leaves and roots of S. kwangsiensis.

Methods

The alkaloids in S. kwangsiensis were characterised using high pressure liquid chromatography coupled with positive electrospray ionisation quadrupole time‐of‐flight tandem mass spectrometry (HPLC‐(+)ESI‐QTOF‐MS/MS). The alkaloid compositions in the leaves and roots were compared by visual inspection combined with principal component analysis (PCA) of the HPLC‐MS data.

Results

Seventy‐five alkaloids comprising aporphine‐, proaporphine‐, protoberberine‐, benzylisoquinoline‐, bisbenzylisoquinoline‐ and morphine‐type alkaloids were identified or tentatively identified in the roots and leaves of S. kwangsiensis. Sixty‐three of these alkaloids have not been previously reported in this species, and three have not been previously reported in the literature. The roots and leaves had similarities in alkaloid composition but differences in the peak intensities of most alkaloids. The PCA revealed that the samples were clustered into two distinct groups, which corresponded to leaves and roots.

Conclusion

This study further clarified the chemical constituents in the roots of S. kwangsiensis, and revealed that diverse alkaloids were also present in the leaves. The comparative chemical profiling of the two parts provides useful information on their potential medicinal use. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
27.
覃艳  黄宁珍  赵志国  李锋   《广西植物》2007,27(3):406-409,413
采用简单序列重复区间扩增(ISSR)分子标记技术对广西地不容3个野生居群和1个引种居群共92个个体进行了遗传多样性研究。10个引物共扩增出61条带,其中60条具多态性,多态性位点百分率为98.36%。4个居群多态性百分率在73.77%~86.89%。Nei’s基因多样性指数(H)为0.3379,Shannon信息多样性指数(Ⅰ)为0.5055。3个野生居群Nei’s遗传分化系数(Gst)表明:83.87%遗传变异分布在居群内,16.13%的遗传变异分布在居群间。引种居群与3个野生居群间的遗传一致度达0.8846。引种居群有效地保护了广西地不容的遗传多样性。  相似文献   
28.
Ten known alkaloids, sinoacutine (Ⅰ), 1-tetrahydropalmatine (Ⅱ), d-stepharine (Ⅲ), 1- stepholidine (Ⅳ), 1-corydalmine (Ⅴ), stephanine (Ⅵ), palmatine (Ⅶ), dehydrocorydalmine (Ⅷ), stepharanine (Ⅸ) and roemerine (Ⅹ) were isolated from the roots of Stephamia yunnanensis H. S. Lo. Their structures were determined from spectral data and chemical evidence.  相似文献   
29.
药用异喹啉生物碱的研究:Ⅱ.白线薯生物碱   总被引:3,自引:0,他引:3  
从白线薯(Stephania brachyandra Diels)的块根中分得四种生物碱,经UV,IR,~1H-NMR,~(13)C-NMR,MS等方法鉴定为:清风藤碱(Sino-acutine,Ⅰ),克斑宁(Crebanine,Ⅱ),荷包牡丹碱(Dicentrine,Ⅲ),千金藤碱(Stephanine,Ⅳ)。其中,清风藤碱和克斑宁系首次从该植物中获得,收率分别高达1.02%和1.39%。清风藤碱的碘甲烷衍生物有一定的松弛横纹肌作用。  相似文献   
30.
从地不容块根中分得四种生物碱A、B、C、D,经UV,IR,~1H-NMR,~(13)C-NMR,HRMS等方法鉴定了它们的结构,分别是cepharanthine (A),1-curine (B),isochondodendrine (C),ushinsunine (D)。C,D系首次从该植物中获得。  相似文献   
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