Polyprenylated xanthones with potential anti-inflammatory and anti-HIV effects from the stems and leaves of Cratoxylum cochinchinense (Lour.) Blume.

ABSTRACT

A phytochemical study on the stems and leaves of Cratoxylum cochinchinense (Lour.) Blume resulted in the isolation and characterisation of a new polyprenylated xanthone, cratocochinone (1), as well as seven known analogues, fuscaxanthone K (2), pruniflorone Q (3), 1,3,5,8-tetrahy-droxy- 2-(3-methybut-2-enyl)-4-(3,7-dimethylocta-2,6-dienyl) xanthone (4), cochinensoxanthone (5), cratoxylum-xanthone B (6), cochinchinone I (7) and cochinchinone K (8). The chemical structure of 1 was determined by comprehensive spectral analyses. The known compounds 2 - 8 were identified by comparing their experimental spectroscopic data with those reported data in the literature. The anti-inflammatory and anti-HIV effects of all isolates 1-8 were evaluated. As a result, compounds 1-8 showed remarkable inhibitory effects against nitric oxide (NO) production induced by lipopolysaccharide in mouse macrophage RAW 264.7 cells showing IC50 values ranging from 0.68 ± 0.06 to 10.27 ± 0.18 µM. Meanwhile, compounds 1-8 displayed notable anti-HIV-1 reverse transcriptase (RT) effects with EC50 values ranging from 0.19 to 10.72 µM.