Soulaxanthone, a new xanthone derivative from .

In search for new metabolites from the stem bark of and , led to the isolation of a new xanthone, soulaxanthone (), along with four other known metabolites, euxanthone (), calopolyanolide E (), calanolide E () and friedelin (). The structures of these compounds were identified and elucidated using spectroscopic techniques such as H NMR,C NMR, COSY, DEPT, HSQC, HMBC, MS and FTIR. The antibacterial activities of compounds -, as well as the extracts, were tested against five bacterial strains.

5,8-Dihy-droxy-2,2-dimethyl-12-(3-methyl-but-2-en-yl)pyrano[3,2-]xanthen-6-one (brasixanthone B).

The title compound (trivial name brasixanthone B), CHO, isolated from , is characterized by a xanthone skeleton of three fused six-membered rings plus an additional fused pyrano ring and one 3-methyl-but-2-enyl side chain. The core xanthone moiety is almost planar, with a maximum deviation 0.057 (4) Å from the mean plane.

Phytochemicals from Hook f. ex T. Anderson and their neuroprotective effects.

Previous phytochemical investigations reported that have biosynthesized a wide range of bioactive phenolics such as xanthones and coumarins. The phytochemical study conducted on the stem bark of has led to the isolation of eight trioxygenated xanthones namely: 5-methoxytrapezifolixanthone , 5-methoxyananixanthone , caloxanthone C , 1,5-dihydroxy-3-methoxy-4-isoprenylxanthone , 6-deoxyisojacareubin , euxanthone , trapezifolixanthone , ananixanthone , together with three common triterpenoids, -sitosterol , friedelin , and stigmasterol . Furthermore, xanthones and were isolated for the first time as naturally occurring xanthones from the plant extract.