Xanthones and other compounds from the latex of garcinia cowa

From our ongoing study on the latex of Garcinia cowa Roxb. ex Choisy collected in Quy Chau, Nghe An province, seven compounds were isolated including four prenylated xanthones: norcowanin (1), kaennacowanol A (2), garcinone D (3), fuscaxanthone I (4); one tocotrienol: parvifoliol F (5) and two triterpenes: stigmasterol (6), lupeol (7). The structures of the isolated compounds were elucidated by physico-chemical spectroscopic analysis and by comparison with reported data. To the best of our knowledge, garcinone D (3), fuscaxanthone I (4) and parvifoliol F (5) were first reported as components of Garcinia cowa.