Sallam_2021_Chem.Biodivers_18_e2000957

A new cytochalasan alkaloid, westalsan (1), along with two known cytochalasan compounds, phomacin B (2) and 19-hydroxy-19,20-dihydrophomacin C (3), were isolated from the solid rice culture of Westerdykella nigra, a marine-derived endophytic fungus, isolated from the roots of mangrove Avicennia marina (Forssk.) Vierh. The structures of compounds 1-3 were established on the basis of extensive 1D and 2D NMR spectroscopic techniques in combination with HR-ESI-MS. The ability of the isolated compounds to inhibit acetylcholine esterase activity was evaluated. Compound 3 showed the highest acetylcholine esterase inhibitory activity (IC(50) 0.056+/-0.003microM), followed by compound 1 (IC(50) 0.088+/-0.005microM) and compound 2 (IC(50) 0.140+/-0.007microM) compared to donepezil (IC(50) 0.035+/-0.002microM). This was further confirmed by molecular docking experiment.