New lignans from the heartwood of Chamaecyparis obtusa var. formosana

Abstract

Four new lignans, 3′,4′-O,O-demethylenehinokinin (1), chamalignolide (2), 8′β-hydroxyhinokinin (3) and 7β,8β- epoxyzuonin A (4), as well as (-)-hinokinin (5), and (-)-zuonin A (6), were isolated from the heartwood of Chamaecyparis obtusa var. formosana. The structures of these lignans were unambiguously determined by spectroscopic methods. And the absolute configuration of 1 was elucidated with a circular dichroism (CD) spectrum. © 2002 Pharmaceutical Society of Japan.