Fusaspirols A-D,novel oxaspirol derivatives isolated from Fusarium solani B-18

Four novel compounds with γ-methylidene-spirobutanolide core, fusaspirols A-D, were isolated from the brown rice culture of Fusarium solani B-18. Their structures were established by extensive spectroscopic analyses of 1D/2D-NMR, HRESITOFMS, and chemical derivatization. The absolute configurations of secondary alcohols in fusaspirols A and D were determined using modified Mosher's ester method. Fusaspirol A and 4,9-di-O-acetylfusaspirol A activated a signaling pathway in osteoclastic differentiation of murine macrophage derived RAW264.7?cells.     

Fusopoltides B–E,new polyketides isolated from Fusarium solani B-18

Four new polyketides, fusopoltides B–E, were isolated, along with four known compounds, from Fusarium solani B-18 cultured on brown-rice. Fusopoltide B is a diastereomer of its co-isolated known compound, fusopoltide A, featuring a pentaleno[1,2-c]pyran ring system. Fusopoltide C and fusopoltides D–E are incorporated the first natural polyketides featured decahydro-pentaleno[1,2-c]pyran and pentaleno[1,2-c]furan ring systems, respectively. The structural assignments were established using comprehensive spectroscopic techniques, the modified Mosher's ester method, and electronic circular dichroism (ECD) calculations.     

Nectrianolins A,B, and C,new metabolites produced by endophytic fungus Nectria pseudotrichia 120-1NP

Two sesquiterpene-epoxycyclohexenone conjugates, nectrianolins A (1) and B (2), together with a sesquiterpene, nectrianolin C (3), were isolated from the brown rice culture of Nectria pseudotrichia 120-1NP, an endophytic fungus isolated from Gliricidia sepium. Their structures were determined on the basis of 1D-/2D-NMR spectroscopy and HRESIMS data analyses in combination with chemical means. Nectrianolins A–C (1–3) exhibited cytotoxic activity against both HL60 and HeLa cells.