Study on secondary metabolites of endophytic fungus Cladosporium sp. JJM22 hosted in Ceriops tagal / 中国中药杂志

Nine secondary metabolites(S)-5-hydroxy-4-methylchroman-2-one(1), 4-methoxynaphthalene-1,5-diol(2), 8-methoxynaphthalene-1,7-diol(3), 1,8-dimethoxynaphthalene(4),(2R,4S)-2,3-dihydro-2-methyl-benzopyran-4,5-diol(5),(2R,4R)-3,4-dihydro-4-methoxy-2-methyl-2H-1-benzopyran-5-ol(6), 7-O-α-D-ribosyl-2,3-dihydro-5-hydroxy-2-methyl-chromen-4-one(7),(R)-3-methoxyl-1-(2,6-dihydroxyphenyl)-butan-1-one(8) and helicascolide A(9) were isolated from endophytic fungus Cladosporium sp. JJM22 by using column chromatographies of silica gel and ODS, and semi-preparative HPLC. Their structures were analyzed on the basis of spectroscopic and chemical data, especially NMR and MS. All isolated compounds were evaluated for their anti-inflammatory activities by examining the inhibitory activities on nitric oxide(NO) production induced by lipopolysaccharide in mouse macrophage RAW264.7 cells in vitro. Compounds 2-4 showed inhibitory activities.

Chemical constituents from fermented Noni juice / 中国中药杂志

The present work was launched to study the chemical constituents from fermented Noni juice. Ten compounds were isolated by using silicagel,Sephadex LH-20 and pre-HPLC. The structures of these compounds were identified by 1D and 2D NMR. Their structures were established as norimester( 1),cyclo( R-Pro-S-Phe)( 2),cyclo-( L-Pro-L-Leu)( 3),trans-cyclo-( D-tryptophanyl-Ltyrosyl)( 4),cyclo( L-Trp-N-methyl-L-Ala-)( 5),4-allyl-2-hydroxyphenyl 1-O-β-D-apiosyl-( 1 → 6)-β-D-glucopyranoside( 6),2-methoxy-4-vinylphenyl β-D-apiofuranosyl-( 1→6)-β-D-glucopyranoside( 7),( +)-lirioresinol A( 8),( ±)-syringaresinol( 9),and2-formyl-1 H-pyrrole-1-butanoic acid( 10). All compounds were tested for their antibacterial activity and α-glucosidase inhibitory activity. Compound 1 was a new compound. All compounds were isolated from fermented Noni juice for the first time. Compound 1 showed significant inhibitory activity against α-glucosidase [IC50 value of( 4. 22±0. 03) μmol·L-1].

A new fatty acid methyl ester from Fissistigma oldhamii inhibiting proliferation of synoviocytes / 中国中药杂志

A new fatty acid methyl ester (1) was isolated from an EtOH extract of Fissistigma oldhamii. It structures was elucidated by a combination of HR-ESI-MS, 1D NMR, 2D NMR, UV, and IR spectroscopic data. The inhibitory effect of compound 1 on the proliferation of primary synovial cells was evaluated. As a result, it showed inhibitory effect on the proliferation of synoviocytes, with IC₅₀ value of 38.6 μmol·L⁻¹.

Chemical constituents from leaves of Rhodomyrtus tomentosa / 中草药

Objective: To study the chemical constituents from the leaves of Rhodomyrtus tomentosa and its antibacterial activities. Methods: The compounds were isolated and purified by various column chromatographies. Their structures were elucidated by means of spectral analyses (MS and NMR). The antibacterial activity of the compounds was tested by micro dilution method Results: A total of 21 compounds were isolated from the 95% ethanol extract in the leaves of R. tomentosa and identified as (2R,4'R,8'R)-α-tocopherol (1), (2R,4'R,8'R)-β-tocopherol (2), α-tocopherol-quinone (3), α-tocopherol A (4), (-)-a-tocospirone (5), rhodomyrtosone F (6), rhodomyrtosone C (7), watsonianone A (8), rhodomyrtone (9), verimol K (10), methyl cinnamate (11), naringenin (12), quercetin (13), myricetin (14), 3,7,3'-trimethoxy-5,4',5'-trihydroxy flavone (15), 5,7,3',5'- tetrahydroxyflavanone (16), blumeatin (17), dihydroquercetin-7,4'-dimethylether (18), dihydroquercetin-4'-dimethoxy (19), 2,4,7,8,9,10-hexahydroxy-3-methoxyanthracene-6-O-β-L-rhamnopyranoside (20), and 4,8,9,10-tetrahydroxy-2,3,7-trimethoxyanthracene-6-O-β-D-glucopyranoside (21). Conclusion: Compound 6 is a new natural product and compounds 2-5, 10-13, and 15-19 are isolated from the plants of Rhodomyrtus (DC.) Reich for the first time. Compounds 3 and 6-9 exhibit the antibacterial activities.

Studies on alkaloids from Fissistigma oldhamii / 中国中药杂志

14 alkaloids were obtained from stems and leaves of Fissistigma oldhamii, by silica gel, ODS, Sephadex LH-20 column chromatographies, and semi-preparative HPLC. Using physicochemical and spectral methods, the isolated alkaloids were identified as norcepharadione B(1), asimilobine(2), lanuginosine(3), laurotanine(4), isocorydine(5), anolobine(6), xylopine(7), N-methylbuxifoline(8), aristolactam AIIIa(9), piperumbellactam A(10), goniopedaline(11), aristololactam BIII(12), liriodenine(13), and salutaridine(14), respectively. Compounds 3-5, 8, 10, 11 and 14 were isolated from the genus Fissistigma for the first time.