The efficient synthesis of （S）-dihydroresorcylide （la） along with trans-resorcylide dimethyl ether （2b）, was achieved in linear 9 steps from commercially available orcinol monohydrate （6） with esterification, carbonylation, and ring-closing metathesis （RCM） as the key steps in the synthetic sequence.
A new trijugin-type limonoid,cipatrijugin G(1),together with the related known cipatrijugin A(2),were isolated from the aerial parts of Cipadessa cinerascens.The structure of the new compound was determined by extensive analysis of its spectroscopic data and by comparison of its NMR data with those reported in the literature.Compound 1 showed cytotoxicity against tumor cell line A549 with an IC_(50) value of 9.78μM.This is the first report of a trijugin-type limonoid bearing aγ-hydroxybutenolide unit,in comparison to the common furan unit as ring E.
