Lepidotrichilins A and B, new protolimonoids with cytotoxic activity from Trichilia lepidota (meliaceae)

Abstract

Two novel protolimonoids, named lepidotrichilins A (1) and B (2), four known protolimonoids, 21,23-epoxy-7α-21α-dihydroxyapotirucalla-14, 24-dien-3-one (3), 21,23- epoxy-7α-21β-dihydroxyapotiru-calla-14,24- dien-3-one (4), dysorone D (5), deoxyflindissone (6), and the two steroids β-sitosterol (7) and stigmasterol (8) were identified in leaves of Trichilia lepidota subsp. schumanniana (Harms) T.D. Pennington. From wood the coumarin scopoletin (9) was isolated. The structures were established by NMR (1D 1H and 13C-NMR and 2D 1H-1H COSY, HMQC and HMBC), mass spectroscopy and infrared (IR) spectral data. The hexane and methanol extracts of the leaves, the protolimonoids lepidotrichilins A (1) and B (2) (IC50 42.7 μg mL-1) and the protolimonoid deoxy-flindissone (6; IC50 9.3 μgmL-1) exhibited significant cytotoxic activity against the MOLT-4 and U937 leukemic cell lines. © 1996-2013 MDPI AG.