Polyketides with Anti-Inflammatory Activity from Trichoderma koningiopsis, a Rhizosphere Fungus from the Medicinal Plant Polygonum paleaceum

Twelve new fungal polyketides, koningiopisins I-P(1-8) and trichoketides C-F(9-12), together with six known congeners(13-18), were isolated from Trichoderma koningiopsis, a rhizosphere fungus obtainedfrom the medicinal plant Polygonum paleaceum. Theirstructures and absolute configurations were established by spectroscopicanalysis, single-crystal X-ray diffraction, the modified Mosher'smethod, chemical derivatization, the octant rule, and C-13 NMR and ECD calculations. Compounds 1-5 are tricyclic polyketides possessing an octahydrochromeneframework with a 6,8-dioxabicyclo[3.2.1]octane core. Compounds 7 and 8 contain a unique ketone carbonyl groupat C-7 and differ from other members of this group of compounds withthe ketone carbonyl group at C-1. Compounds 1, 2, and 13 showed inhibitory activity on LPS-inducedBV-2 cells on NO production with IC50 values of 14 & PLUSMN;1, 3.0 & PLUSMN; 0.5, and 8.9 & PLUSMN; 2.7 & mu;M, respectively.

Automated summary

Twelve new fungal polyketides, koningiopisins I-P(1-8) and trichoketides C-F(9-12), together with six known congeners(13-18), were isolated from Trichoderma koningiopsis, a rhizosphere fungus obtained from the medicinal plant Polygonum paleaceum. Their structures and absolute configurations were established by spectroscopic analysis, single-crystal X-ray diffraction, the modified Mosher's method, chemical derivatization, the octant rule, and C-13 NMR and ECD calculations. Compounds 1-5 are tricyclic polyketides possessing an octahydrochromene framework with a 6,8-dioxabicyclo[3.2.1]octane core. Compounds 7 and 8 contain a unique ketone carbonyl group at C-7 and differ from other members of this group of compounds with the ketone carbonyl group at C-1. Compounds 1, 2, and 13 showed inhibitory activity on LPS-induced BV-2 cells on NO production with IC50 values of 14±1, 3.0±0.5, and 8.9±2.7µM, respectively.