ABSTRACT
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
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.
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.
ABSTRACT
<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
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.