Three new biphenyls from the twigs of Garcinia tetralata and their anti-tobacco mosaic virus activity.

Phytochemical investigations on the ethanol extract of the twigs of Garcinia tetralata resulted in the isolation of three new biphenyls, tetralatabiphenyls A-C (1-3), along with three known biphenyl derivatives (4-6). Structural elucidations of 1-3 were performed by spectroscopic methods such as 1D and 2D NMR spectra, in addition to high-resolution mass spectra. Compounds 1-6 were also evaluated for their anti-tobacco mosaic virus (anti-TMV) activity. The results showed that compound 3 showed high anti-TMV activity with inhibition rate of 31.1%. Compounds 1, 2, and 4-6 also showed modest anti-TMV activities with inhibition rates in the range of 18.9-24.5%, respectively.