A new diterpenoid acid from the rosin of Pinus kesiya var. langbianensis (A.Chev.) Gaussen ex Bui

One undescribed diterpenoid acid and six compounds were isolated from the 95% ethanol fraction of Pinus kesiya var. langbianensis (A.Chev.) Gaussen ex Bui resin by using various chromatographic methods, including MCI Gel, Sephadex LH-20, ODS, silica gel and semi-preparative HPLC. The planar structures were identified by spectroscopy methods (1D, 2D NMR, UV, IR, MS, etc.), and the absolute configuration of the new compound was determined by ECD calculation. Compound 1 is a new compound, and compounds 2, 5-7 were isolated from Pinus kesiya var. langbianensis (A.Chev.) Gaussen ex Bui for the first time.