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Published on: April 21, 2018
Cholinesterase inhibitors from Cleistocalyx operculatus buds
Byung Sun Min1, To Dao Cuong, Joo-Sang Lee
1College of Pharmacy, Catholic University of Daegu, Gyeongsan, Korea. bsmin@cu.ac.kr
Abstract:
Five flavonoids, myricetin-3'-methylether 3-O-β-D: -galactopyranoside (1), myricetin-3',5'-dimethylether 3-O-β-D: -galactopyranoside (2), quercetin (3), kaempferol (4), and tamarixetin (5) were isolated from the buds of Cleistocalyx operculatus (Myrtaceae). The chemical structures of these compounds were determined on the basis of spectroscopic analyses, including 2D NMR. Their anti-Alzheimer effects were evaluated via acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activity assays. All five compounds 1-5 showed potential inhibitory activities against AChE with IC(50) values of 19.9, 37.8, 25.9, 30.4 and 22.3 μM, respectively, while compounds 1, 3, 4 and 5 also possessed BChE inhibitory activity with IC(50) values of 152.5, 177.8, 62.5, and 160.6 μM, respectively.
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