New urushiols with platelet aggregation inhibitory activities from resin of Toxicodendron vernicifluum

Abstract Eight new urushiol-type compounds ( 1 – 7b ), along with seven known compounds were isolated from the resin of Toxicodendron vernicifluum Stokes. Their structures were determined by extensive spectroscopic methods, included 1 H NMR, 13 C NMR, HMQC, HMBC, HRESIMS, EI-MS in combination with CD methods. All the compounds except 7a and 7b were evaluated for their anti-platelet aggregation activities in vitro. Among them, compound 5 (IC 50  = 5.12 ± 0.85 μmol/L), with a vic -diol moiety in the long alkyl chain showed the most potent inhibitory of platelet aggregation activity induced by ADP. In addition, compound 6 showed the effect of anti-platelet aggregation induced by AA with the IC 50 value of 3.09 ± 0.70 μmol/L. Thus, these compounds might be the active components to the traditional use of Resina Toxicodendri for breaking up blood stasis, which could be related to the anti-platelet aggregation.