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He ZD Ma CY Zhang HJ Tan GT Tamez P Sydara K Bouamanivong S Southavong B Soejarto DD Pezzuto JM Fong HH 《化学与生物多样性》2005,2(10):1378-1386
Bioassay-guided fractionation of the antimalarial-active CHCl3 extract of the dried stem of Nauclea orientalis (L.) L. (Rubiaceae) has resulted in the isolation of two novel tetrahydro-beta-carboline monoterpene alkaloid glucosides, naucleaorine (= (16alpha,17beta)-3,14:15,20-tetradehydro-16-ethenyl-17-(beta-D-glucopyranosyloxy)-19alpha-methoxyoxayohimban-21-one; 1) and epimethoxynaucleaorine (2), as well as the known compounds, strictosidine lactam (= (15beta,16alpha,17beta)-19,20-didehydro-16-ethenyl-17-(beta-D-glucopyranosyloxy)oxayohimban-21-one; 3), 3,4,5-trimethoxyphenol (4), 3alpha-hydroxyurs-12-en-28-oic acid methyl ester (5), 3alpha,23-dihydroxyurs-12-en-28-oic acid (6), 3alpha,19alpha,23-trihydroxyurs-12-en-28-oic acid methyl ester (7), and oleanolic acid (8). Compounds 1, 2, 6, and 8 showed moderate in vitro activities against Plasmodium falciparum. Their structures and configurations were elucidated by spectroscopic methods including 1D- and 2D-NMR analyses. 相似文献
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He ZD Ma CY Tan GT Sydara K Tamez P Southavong B Bouamanivong S Soejarto DD Pezzuto JM Fong HH Zhang HJ 《Phytochemistry》2006,67(13):1378-1384
Bioassay-directed fractionation of the antimalarial active CHCl(3) extract of the dried stems of Rourea minor (Gaertn.) Aubl. (Connaraceae) liana led to isolation of two glycosides, rourinoside (1) and rouremin (2), as well as five known compounds, 1-(26-hydroxyhexacosanoyl)-glycerol (3), 1-O-beta-D-glucopyranosyl-(2S,3R,4E-8Z)-2-N-(2'-hydroxypalmitoyl)-octadecasphinga-4,8-dienine, 9S,12S,13S-trihydroxy-10E-octadecenoic acid, dihydrovomifoliol-9-beta-D-glucopyranoside, and beta-sitosterol glucoside. Compounds 1-3 showed weak in vitro activities against Plasmodium falciparum. Their structures and stereochemistry were elucidated by spectroscopic methods and selected enzyme hydrolysis. 相似文献
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Population genetic structure of the endemic rosewoods Dalbergia cochinchinensis and D. oliveri at a regional scale reflects the Indochinese landscape and life‐history traits
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Ida Hartvig Thea So Suchitra Changtragoon Hoa Thi Tran Somsanith Bouamanivong Ida Theilade Erik Dahl Kjær Lene Rostgaard Nielsen 《Ecology and evolution》2018,8(1):530-545
Indochina is a biodiversity hot spot and harbors a high number of endemic species, most of which are poorly studied. This study explores the genetic structure and reproductive system of the threatened endemic timber species Dalbergia cochinchinensis and Dalbergia oliveri using microsatellite data from populations across Indochina and relates it to landscape characteristics and life‐history traits. We found that the major water bodies in the region, Mekong and Tonle Sap, represented barriers to gene flow and that higher levels of genetic diversity were found in populations in the center of the distribution area, particularly in Cambodia. We suggest that this pattern is ancient, reflecting the demographic history of the species and possible location of refugia during earlier time periods with limited forest cover, which was supported by signs of old genetic bottlenecks. The D. oliveri populations had generally high levels of genetic diversity (mean He = 0.73), but also strong genetic differentiation among populations (global GST = 0.13), while D. cochinchinensis had a moderate level of genetic diversity (mean He = 0.55), and an even stronger level of differentiation (global GST = 0.25). These differences in genetic structure can be accounted for by a higher level of gene flow in D. oliveri due to a higher dispersal capacity, but also by the broader distribution area for D. oliveri, and the pioneer characteristics of D. cochinchinensis. This study represents the first detailed analysis of landscape genetics for tree species in Indochina, and the found patterns might be common for other species with similar ecology. 相似文献
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Cui‐Ying Ma Sebisubi Fred Musoke Ghee Teng Tan Kongmany Sydara Somsanith Bouamanivong Bounhoong Southavong D. Doel Soejarto Harry H. S. Fong Hong‐Jie Zhang 《化学与生物多样性》2008,5(11):2442-2448
Bioassay‐directed fractionation led to the isolation of seven compounds from a sample of the dried leaves, twigs, and branches of Diospyros quaesita Thw . (Ebenaceae). One of the isolates, betulinic acid 3‐caffeate ( 1 ), showed in vitro antimalarial activity against Plasmodium falciparum clones D6 (chloroquine‐sensitive) and W2 (chloroquine‐resistant) with IC50 values of 1.40 and 0.98 μM , respectively. Evaluation of compound 1 in the human oral epidermoid (KB) cancer cell line revealed cytotoxicity at ED50 of 4.0 μM . In an attempt to reduce the cytotoxicity of 1 , the acetylated derivative 1a and betulinic acid ( 1b ) were prepared. Of the seven isolates, diospyrosin ( 2 ) was determined to be a new neolignan. In addition to 1 , other known compounds isolated in this study were pinoresinol, lariciresinol, N‐benzoyl‐L ‐phenylalaninol, scopoletin, and poriferast‐5‐en‐3β,7α‐diol. The structure of 2 was elucidated based on spectroscopic data analysis including 1D‐ and 2D‐NMR, and HR‐ESI‐MS. 相似文献
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