Biflavanoids and a flavanone-chromone from the leaves of Garcinia dulcis(Roxb.) Kurz

Abstract

From the leaves of Garcinia dulcis(Roxb) Kurz a series of biflavanoids were isolated. Morelloflavone was characterised as its heptamethyl ether; it forms an octa-acetate by ring opening of ring I-C. GB-2a forms an octamethyl ether having a naringenin unit linked to a chalcone. By methylation, volkensiflavone and amentoflavone were isolated (as their hexamethyl ethers); methylation of a minor component gave the novel I-4′,I-5,II-5,I-7,II-7-pentamethoxyflavanone[I-3,II-8]chromone.