Two new polyketides from a marine sediment-derived fungusEutypella scopariaFS26

Abstract

Two new polyketides, 7,8-dihydroxy-3,5,7-trimethyl-8,8a-dihydro-1H-isochromen-6(7H)-one (1) and 6-(hydroxymethyl)-2,2-dimethyl-3,4-dihydro-2H-chromene-3,4-diol (2), together with a known nitrogen-containing polyketide (cytochalasin-type of metabolites), [12]-cytochalasin (3), have been isolated from the fermentation broth of a marine sediment-derived fungus Eutypella scoparia FS26 obtained from the South China Sea. Their structures were elucidated by spectroscopic methods, mainly 1D and 2D NMR spectroscopic techniques. The absolute configurations of compound 1 were determined by NOESY analysis and the literature data were compared with circular dichroism (CD) spectroscopy. The cytotoxic effects on MCF-7, NCI-H460 and SF-268 cell lines of all compounds were evaluated by the sulforhodamine B method.

Marine natural products

“…(sea cucumber Holothuria nobilis, S. China Sea) produced the 12-membered macrolides dendrodolide A-M 281-293 (dendrodolides A-E, G-I, K and L had modest inhibitory activity against two HTCLs), 261 while the polyketides 294 and 295 were obtained from Eutypella scoparia (sediment, S. China Sea). 262 Gymnascella dankaliensis (sponge Halichondria japonica, Osaka Bay, Japan) 263 provided dankastatin C 296, a polyketide tyrosine derivative with potent growth inhibition of P388 cells. 264 Hypocreales sp.…”

Six New Vibralactone Derivatives from Cultures of the Fungus Boreostereum vibrans

“…All these evidences suggested that 5 was an acetylation derivative of (3 S *,4 R *)-6-(hydroxymethyl)-2,2-dimethyl-3,4-dihydro-2 H -chromene-3,4-diol at the position of hydromethyl group. (3 S *,4 R *)-6-(Hydroxymethyl)-2,2-dimethyl-3,4-dihydro-2 H -chromene-3,4-diol was isolated from the fermentation broth of a marine sediment-derived fungus Eutypella scoparia FS26 obtained from the South China Sea as one of the two new polyketides [ 17 ]. Thus, compound 5 was established as (3 S *,4 R *)-6-acetoxymethyl-2,2-dimethyl-3,4-dihydro-2 H -chromene-3,4-diol, as shown in Fig.…”

Two new xyloketals from the endophytic fungus Endomelanconiopsis endophytica derived from medicinal plant Ficus hirta

“…The cell growth inhibitory activities of compounds 1-5 against four human tumor cell lines (SF-268, MCF-7, NCI-H460, and HepG-2) were tested using the previously published methods [16,17].…”