Chemical modification and structure-activity relationships of pyripyropenes. 1. Modification at the four hydroxyl groups
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Syntheses, Crystallization, and Spectroscopic Characterization of 3,5-Lutidine N-Oxide Dehydrate
Published on: April 24, 2018
1Research Center for Biological Function, Kitasato Institute, Kitasato University, Tokyo, Japan.
Abstract:
Four hydroxyl groups of pyripyropenes have been modified and evaluated for their ability to inhibit microsomal acyl-CoA:cholesterol acyltransferase (ACAT) activity in vitro and to lower cholesterol absorption in vivo in a cholesterol-fed hamster. 7-O-n-Valeryl derivative (8c) improved the in vitro ACAT inhibitory activity (IC50 = 13 nM) about 7 times better than pyripyropene A. Introduction of methanesulfonyl group at 11-hydroxyl group (17a) increased both in vitro activity (IC50 = 19 nM) and in vivo efficacy (ED50 = 10 mg/kg).
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