A prenylated acridone alkaloid and ferulate xanthone from barks of Citrus medica (Rutaceae)

Abstract

A new prenylated acridone alkaloid, medicacridone (1), and a new ferulate xanthone, medicaxanthone (5), together with 11 known compounds were isolated from the methanol extract of the bark of the Cameroonian medicinal plant Citrus medica. The structures of all compounds were determined by comprehensive analyses of their 1D and 2D NMR, mass spectral (EI and ESI) data, chemical reactions, and comparison with previously known analogues. The agar diffusion test delivered low to missing antimicrobial activities, corresponding with MICs > 1 mg mL-1, while compounds 1-6 and atalantoflavone (9) displayed weak cytotoxic activity against the human Caucasian prostate adenocarcinoma cell line PC-3, with IC50 values ranging from 60.5 to 80.0 μm versus doxorubicine with IC50=0.9 μm.