Concise access to primin, miconidin and related natural resorcinols

摘要

An efficient and short synthetic procedures affording the biologically active natural products primin, miconidin, olivetol, grevillol, and cardol (adipostatin A) in high yields are reported. The two strategies involve Sonogashira and Suzuki cross-couplings as the crucial steps for the installation of the alkyl side chains. Syntheses start from cheap, commercially available 1-bromo-3,5-dimethoxybenezene to obtain 1,3-dimethoxy-5-(alk-1-yn-1-yl)benzene as the key intermediate. This intermediate can be easily and economically oxidized to provide primin in excellent overall yield while avoiding undesired side products by the virtue of its symmetry. The demethylation of the key intermediate affords natural resorcinols olivetol, grevillol, and cardol, respectively. The reduction of primin provides its hydroquinone derivative miconidin. (C) 2017 Elsevier Ltd. All rights reserved.