A New Ring-Reduced Tetraprenyltoluquinone and a Prenylated Xanthone from Garcinia cowa

Abstract

The methanolic extract of the stem bark of Garcinia cowa Roxb. (Guttiferae) yielded (2E,6E,10E)-(+)-4β-hydroxy-3-methyl-5β-(3,7,11,15-tetramethylhexadeca-2,6,10,14-tetraenyl)cyclohex-2-en-1-one 1, 4-(1,1-dimethyl-prop-2-enyl)-1,5,6-trihydroxy-3-methoxy-2-(3-methylbut-2-enyl)xanthen-9(9H)-one 2, and the known compound rubraxanthone 3. The structural conclusions are based on spectroscopic data.