Abstract
AbstractAsymmetric synthesis of (2S,3S,4R,5S)-2-(2,4-dihydroxyphenyl)-5-(4-methoxyphenyl)-3,4-dimethyltetrahydrofuran, named as ent-anorisol A, was accomplished. The uncommon relative 2,3-anti-3,4-syn-4,5-syn stereochemistry across the tetrahydrofuran ring of ent-anorisol A was constructed with high yield and good stereoselectivity via an acid-catalyzed direct cyclization of unprotected chiral 1,4-diarylbutane-1,4-diol with non-symmetrical aromatic rings. Except for the sign of the specific rotation value, the spectroscopic data of the synthetic ent-anorisol A are in good agreement with those reported for natural anorisol A isolated from Anogeissus rivularis. In addition, the (2R,3S,4R,5R) and (2S,3S,4R,5R) isomers of anorisol A were also synthesized. Comparison of the specific rotation value and the experimental electronic circular dichroism data of natural anorisol A with those of the synthesized ent-anorisol A, (2R,3S,4R,5R), and (2S,3S,4R,5R) derivatives confirms the 2R,3R,4S,5R configurations assigned for natural anorisol A.
Funder
National Research Council of Thailand
Mahidol University
Center of Excellence for Innovation in Chemistry
Ministry of Higher Education, Science, Research and Innovation, Thailand
Office of the Higher Education Commission
Subject
Organic Chemistry,Catalysis