Three novel xanthones from Garcinia paucinervis and their anti-TMV activity.

Phytochemical investigations of the leaves of Garcinia paucinervis resulted in the isolation of three new xanthones 1-3 and five known analogues 4-8. Structural elucidations of 1-3 were performed by spectral methods such as 1D and 2D (HMQC, HMBC, and ROESY) NMR spectroscopy, in addition to high resolution mass spectrometry. Compounds 1-3 showed anti-TMV activities, with inhibition rates above 20%, especially for 1, which had a lower IC₅₀ value of 21.4 µM.