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A new steroid with a long cross-conjugation structure, 15a-hydroxy-(22E, 24R)-ergosta-3, 5, 8 (14), 22-tetraen-7-one (1), was isolated from the marine-derived fungus Aspergillus aculeatus. Its structure was established by the extensive spectroscopic analyses, and its cytotoxicities against P388, HL-60, and PC-3 cell lines were measured in vitro.
ABSTRACT
In the structural determination of natural glycosides, nuclear magnetic resonance (NMR) is an important approach in determining the configuration of glycoside bond. The test of coupling constant of the anomeric proton and chemical shift of the anomeric carbon are two common methods, but these methods are not suitable for some sugars. For those sugars, detailed 13C NMR analysis is an alternative choice. This paper summarizes the characteristics of 1H and 13C NMR data of the common monosaccharides published in the literatures, in order to search an approach to determine the configuration of glycoside bond.
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<p><b>OBJECTIVE</b>To study the chemical constituents of leaves of Albizia chinensis.</p><p><b>METHOD</b>The chemical constituents were isolated and repeatedly purified with column chromatography. The structures were elucidated by physicochemical properties and spectroscopic methods.</p><p><b>RESULT</b>Eight compounds were isolated from the 95% ethanol extract of the leaves of A. chinensis and their structures were elucidated as quercetin 3'-O-beta-D-glucopyranosyl-3-O-rutinoside (1), kaempferol 3,7-di-O-beta-D-glucopyranoside (2), rutin (3), D-pinitol (4), luteolin 7-O-beta-D-glucopyranoside (5), (+)-lyoniresinol 3alpha-O-beta-D-glucopyranoside (6), (-)-lyoniresinol 3alpha-O-beta-D-glucopyranoside (7), syringin (8).</p><p><b>CONCLUSION</b>Compound 1, 2, 4, 6-8 were isolated from this genus for the first time, and compound 3 and 5 were obtained from this plant for the first time.</p>
Subject(s)
Albizzia , Chemistry , Plant Extracts , Chemistry , Plant Leaves , ChemistryABSTRACT
<p><b>OBJECTIVE</b>To study the chemical constituents of the roots of Incarvillea mairei.</p><p><b>METHOD</b>The chemical constituents were isolated and purified by chromatographic techniques with silica gel, Sephadex LH-20 column, and preparative TLC. Structures of the compounds were identified by spectroscopic methods.</p><p><b>RESULT</b>Seven compounds were obtained and elucidated as 1-O-methyl-guaiacylglycerol (1), 1-O-feruloyl-3-O-(26"-hydroxylhexacosoyl) glycerol (2), incarvine D (3), piceid (4), 6'-8"E, 11"E-octadecadienoyl-clionasterol-3-glucoside (5), beta-sitosterol (6), and beta-daucosterol (7).</p><p><b>CONCLUSION</b>Compounds 1-7 were isolated from I. mairei, and among them 1 and 2 were new compounds, 4, 5 were isolated from the genus Incarvillea for the first time.</p>
Subject(s)
Bignoniaceae , Chemistry , Drugs, Chinese Herbal , Chemistry , Plant Roots , Chemistry , Spectrometry, Mass, Electrospray IonizationABSTRACT
Object To study the chemical constituents from the roots of Stellera chamaejasme L. Methods Chemical constituents were isolated by chromatographic methods and identified by physiochemical and spectral analysis. Results One lignan and three biflavonoids were purified and determined as bursehernin (Ⅰ), chamaejasmenin B (Ⅱ), isoneochamaejasmin A (Ⅲ),and (+)-chamaejasmin (Ⅳ). Conclusion Compound Ⅲ and Ⅳ are determined as new optical compounds. Compound I is first isolated from Stellera L. species.
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Objective To study the chemical constituents in Sparganium stoloniferum. Methods The compounds were isolated by repeated silica gel and Sephadex LH-20 chromatographies. The structures of isolated compounds were identified by analysis of their spectral data and chemical reactions. Results Nine compounds were isolated and their structures were identified as daucosterol palmitate (Ⅰ), ?-sitosterol palmitate (Ⅱ), 24-methylenecycloartanol (Ⅲ), 6, 7, 10-trihydroxy-8-octadecenoic acid (Ⅳ), vanillic acid (Ⅴ), p-hydroxybenzaldehyde (Ⅵ), 2,3-dihydroxypropyl palmitate (Ⅶ), 5-hydroxymethyl-2-furaldehyde (Ⅷ), ?-sitosterol (Ⅸ). Conclusion Compounds Ⅰ-Ⅲ and Ⅴ-Ⅷ are obtained from the plants of Sparganium L. for the first time.