ABSTRACT
Based on ethnomedicinal and chemotaxonomic records of Ficus plants, Ficussur Forssk was studied in the search for bioactive compounds. Eleven known compounds including mixture α -amyrin acetate and ß -amyrin acetate (1 and 2), lupeol (3), 3ß-acetoxy-olean-12-en-11-one (4), lupenyl acetate (5), taraxastan-3,20-diol (6), 3'- (3-methylbut-2-enyl) biochanin A (7), derrone (8), quercetin (9), stigmasterol (10), and stigmasterol glycoside (11) were isolated from stem barks of Ficus sur Forssk. Their structures were obtained through analysis of spectroscopic data (1D and 2D NMR), mass spectrometry, and by comparison of these data with the literature. Nine isolated compounds (1-7, 10, 11) were tested as the active wighteone metabolite previously isolated from the roots of this plant against the human HepG2 hepatocellular carcinoma cells and a small panel of sensitive microbial strains for structure- activity relationship purpose. The compounds didn't show any activity. With the aim of understanding the impact of the structural difference between wighteone metabolite and its analogs, the former were cross-docked to evaluate their anticancer properties via the apoptosis pathway. Wighteone metabolite proved to be the best ligand confirming its previous bioassay result. Thus, the current study lays the framework for the further optimization of wighteone metabolite regarding its anticancer activity.
ABSTRACT
The chemical investigation of the methanolic root extract of Caloncoba glauca (P. Beauv.) Gilg exhibited two new 30-norfriedelane triterpenes, glaucalactones A and B (1-2), together with eight known compounds, caloncobalactone (3), friedelin (4), friedelanol (5), 3-oxo-friedelan-28-oic acid (6), stigmasterol (7), ß-sitosterol (8), ß-sitosterol-3-O-ß-D-glucopyranoside (9) and pentacosanoic acid (10). The structures of the isolates were elucidated by extensive spectroscopic and spectrometric analyses (1D and 2D NMR, ESI-MS) and by comparison with previously reported data. All the compounds were tested for their antioxidant, antifungal and antibacterial activities. Compound 1 displayed weak antibacterial effect with MIC value of 125 µg/mL against Staphylococcus aureus and Escherishia coli. Compound 6 exhibited moderated antifungal activity against Candida krusei with MIC value of 62.5 µg/mL. All the isolates were found to be inactive as antioxidants in the DPPH, ABTS and FRAP assays.
ABSTRACT
Phytochemical investigation of the aerial roots of Ficus sur, a Cameroonian medicinal plant, resulted in a previously undescribed cerebroside, suroside (1), in addition to its aglycon congener suramide (2). Moreover, six known natural products including alpinumisoflavone (3), wighteone metabolite (4), oleanolic acid (5), ß-sitosterol (6), ß-sitosterol-3-O-ß-D-glucopyranoside (7), and epi-ѱ-taraxastanolone (8) were identified. The structures of the previously undescribed compounds were determined by analysis of 1D and 2D-NMR (One and two dimensional nuclear magnetic resonance), mass spectrometry, chemical conversion, and by comparison of these data with those from the literature. Wighteone metabolite (4) exhibited a weak cytotoxic activity against the human HepG2 hepatocellular carcinoma cells with an IC50 value of 51.9 µM.