ABSTRACT
Objective To study the chemical constituents of sesquiterpenoids of agarwood from Aquilaria crassna. Methods Seven squiterpenoids were isolated and purified by various column chromatographic techniques and HPLC method. The structures of the compounds were identified through the combined analysis of physicochemical properties and spectral data. The acetylcholinesterase and α-glucosidase inhibitory activity of compounds were evaluated by Ellman colorimetric method and pNPG method, respectively. Results Seven compounds were isolated from the ethyl acetate extract obtained from 95% aq. ethanol extract of agarwood from Aquilaria crassna and were identified as 2-[(2β,8β,8aα)-8,8a-dimethyl-1,2,3,4,6,7,8,8a-octahydro naphthalen-2-yl]-3- hydroxy-2-methoxpropanoic acid (1), 2-[(2β,8α,8aα)-8,8a-dimethyl-1,2,3,4,6,7,8,8a-octahydronaphthalen-2-yl] propane-1,2-diol (2), (1β,3α,4aβ,5β,8aα)-4,4a-dimethyl-6 (prop-1-en-2-yl) octahydronaphtha-lene-1,8a(1H)-diol (3), eremophila-9-en-8β,11-diol (4), eudesma-4-en-8,11-diol (5), eudesma-4-en-11,15-diol (6), and methyl-15-oxo-eudesmane-4,11 (13)-dien-12-oate (7). Moreover, compounds 1, 4 and 5 showed acetylcholinesterase inhibitory activity, and compound 5 exhibited α-glucosidase inhibitory activity.Conclusion Compound 1 is a new compound named as crasscid A, and compounds 1-3 and 7 are obtained from agarwood for the first time.