Search

A new isoprenylated sanggenon-type flavanone, nigrasin K (1), together with three known analogs (2-4) and five known Diels-Alder adducts (5-9), were isolated from the twigs of Morus nigra. Their structures were elucidated by spectroscopic methods. Sanggenon M (2), chalcomoracin (5), sorocein H (6), kuwanon J (7), sanggenon C (8), and sanggenon O (9) showed significant inhibitory effects on mushroom tyrosinase. [ABSTRACT FROM AUTHOR]

A new brominated polyacetylene, xestonariene I (1), along with three known related analogues (2–4), was obtained from Chinese marine spongeXestospongia testudinaria. Its structure was determined on the basis of detailed spectroscopic analysis and by comparison with literature data. Compound4exhibited significant inhibitory activity against pancreatic lipase, which plays a key role in preventing obesity, with an IC50value of 0.61 μM, being comparable to that of the positive control orlistat (IC50 = 0.78 μM). [ABSTRACT FROM PUBLISHER]

Xestospongic acid methyl ester, a naturally brominated fatty acid with potent pancreatic lipase inhibitory activity in vitro, was synthesized from 5-hexynol in 30% total yield. [ABSTRACT FROM AUTHOR]

Phytochemical investigation of the stem of Morus notabilis led to the isolation and characterization of 10 compounds of 2-arylbenzofurans (1–10), including two new compounds, (2′R)-2′,3′-dihydro-2′-(1-hydroxy-1-methylethyl)-2,6′-bibenzofuran-6,4′-diol (1) and 5,6-dimethoxy-2-(3-hydroxy-5-methoxyphenyl)benzofuran (2). Moracins O (6) and P (10) showed inhibitory effects on mushroom tyrosinase with IC50 values being lower than that of kojic acid. [ABSTRACT FROM AUTHOR]

The microbiological transformation of epothilone A (1) by Aspergillus niger AS 3.739 afforded four main metabolites. Their structures were elucidated by 1H, 13C NMR and HSQC, COSY, HMBC, and NOESY spectra as trans-12,13-hydroxylated epothilone A (2), cis-12,13-hydroxylated epothilone A (3), trans-12,15-epoxidated epothilone A (4), and cis-12,15-epoxidated epothilone A (5). All four compounds were firstly found based on their stereochemistry. These new compounds displayed cytotoxicity against human breast carcinoma cells MCF-7 with IC50 9.88 μg/ml of 2, 2.52 μg/ml of 3, 9.88 μg/ml of 4, and 5.68 μg/ml of 5. [ABSTRACT FROM AUTHOR]