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As one of the most lethal diseases, pancreatic cancer shows a dismal overall prognosis and high resistance to most treatment modalities. Furthermore, pancreatic cancer escapes early detection during the curable period because early symptoms rarely emerge and specific markers for this disease have not been found. Although combinations of new drugs, multimodal therapies, and adjuvants prolong survival, most patients still relapse after surgery and eventually die. Consequently, the search for more effective treatments for pancreatic cancer is highly relevant and justified. As a newly re-discovered mediator of gasotransmission, hydrogen sulfide (H
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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.
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To study the secondary metabolites of a marine-derived fungus Ascotricha sp. ZJ-M-5, several chromatographic methods including macroporous resin, silica gel, ODS and Sephadex LH-20 were used to isolate the compounds, and their structures were elucidated on the basis of physicochemical properties and spectroscopic methods. Ten compounds were obtained and identified as ascotrichic acid B (1), (3R)-6-hydroxymellein (2), beta-carboline (3), (22E, 24R)-ergosta-7, 22-diene-3beta, 5alpha, 6beta-triol (4), (22E, 24R)-ergosta-7, 22-diene-3beta, 5alpha, 6beta, 9alpha-tetraol (5), cyclo (Leu-Pro) (6), cyclo (Ile-Leu) (7), cyclo (Pro-Val) (8), cyclo (Pro-Gly) (9), and cyclo (Hpro-Ala) (10). Among them, compound 1 is a new 3, 4-seco-lanostane triterpenoid which has been isolated from the filamentous fungi for the first time, and compounds 2-10 are firstly isolated from Ascotricha genus.
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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 constituents in the chloroform extract of olibanum and their antitumor activities.</p><p><b>METHOD</b>The compounds were isolated by chromatographic methods and their structures were identified on the basis of spectroscopic methods and X-ray diffraction. The antiproliferative effect of the compounds in human leukemia HL-60 cells was tested by viable cell counting.</p><p><b>RESULT</b>Four cembrane diterpenes were isolated and identified as incensole-oxide (1), acetyl incensole-oxide (2), incensole (3), and acetyl incensole (4).</p><p><b>CONCLUSION</b>Compounds 2 and 4 were isolated from the genus Boswellia for the first time. Compound 4 showed growth inhibitory effect against human leukemia HL-60 cell lines with IG50 value of (16.3 +/- 3.4) micromol x L(-1).</p>
Subject(s)
Humans , Antineoplastic Agents, Phytogenic , Chemistry , Pharmacology , Boswellia , Chemistry , Cell Line, Tumor , Cell Proliferation , Diterpenes , Chemistry , Pharmacology , Plant Extracts , Chemistry , PharmacologyABSTRACT
<p><b>OBJECTIVE</b>To study the chemical constituents of the flavonoids from Sophora tonkinensis.</p><p><b>METHOD</b>The compounds were isolated by chromatography on silica gel, Sephadex LH-20 column and identified by spectroscopic analysis.</p><p><b>RESULT</b>Eight compounds were isolated and their structures were identified as tonkinochromane I (1), glabrol (3), lupinifolin (2), tonkinensisol (4), 8-C-prenylkaempferol (5), 7,2'-dihydroxy-4'-methoxy-isoflavanol (6), formononetin (7), and genistein (8), respectively.</p><p><b>CONCLUSION</b>Compound 1 was a new compound. And compound 6 was firstly isolated from the genus Sophora. Compounds 2, 3 and 5 were isolated from S. tonkinensis for the first time.</p>
Subject(s)
Chromatography, High Pressure Liquid , Flavonoids , Chemistry , Genistein , Isoflavones , Rhizome , Chemistry , Sophora , ChemistryABSTRACT
Objective To study the chemical constituents from mycelium of marine fungus Aspergillus versicolor.Methods The compounds were separated by column chromatography and their structures were elucidated based on chemical and spectral analysis. Results Seven compounds have been isolated from the acetone and methanol extracts from the mycelia of Aspergillus versicolor. Their structures were determined as sterigmatocystin (I), 6-methoxysterigmatocystin (II), averufin (III), tyrosine (IV), 3-methyl-pyrrolopiperazine-2, 5-dione (V), 3-isopropyl-pyrrolopiperazine-2, 5-dione (VI), carbamide (VII). Conclusion Compounds IV,V and VI were isolated for the first time from this genus of marine fungi.
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Objective To study the chemical constituents from the wing twigs of Euonymus alatus. Methods Compounds were isolated and purified repeatedly on silica gel, Sephadex LH-20, open RP-C18 column chromatographies and PTLC, and their chemical structures were elucidated by their physicochemical properties and spectral data, such as 1H-NMR, 13C-NMR, and EI-MS. Results Nine compounds were obtained and identified as: epifriedelinol (Ⅰ), stigmast-4-en-3-one (Ⅱ), 6?-hydroxy-stigmast-4-en-3-one (Ⅲ), ?-sitosterol (Ⅳ), methyl 2, 4-dihydroxy-3, 6-dimethyl benzoate (Ⅴ), methyl 2, 4-dihydroxy-6-methyl benzoate (Ⅵ), 7-methoxy-4-methylphthalide (Ⅶ), vanillin (Ⅷ), n-octacosanol (Ⅸ). Conclusion Compound Ⅶ is first reported as a natural product. Compounds Ⅴ-Ⅷ are reported from plants of Euonymus L. for the first time.
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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.
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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.