RESUMEN
Objective: To study the chemical constituents from the barks of Quercus mongolica. Methods: The chemical constituents were isolated and purified on the base of silica gel column chromatography and HPLC method. The structural elucidation was performed according to the physicochemical properties and spectral analysis. Results: Twenty compounds were isolated and identified as taraxerone (1), taraxerol (2), 20β-hydroxydammara-23-en-3-one (3), 20 (S), 24 (S)-dihydroxydammara-26-en-3-one (4), ursotic acid acetate (5), lupeol (6), β-sitosterone (7), isofouquierol (8), gallic acid (9), 5, 6, 7, 4'-tetrahydroxyflavanone (10), taxifolin (11), scopoletin (12), kaempferol (13), β-sitosterol (14), secoisolariciresinol (15), erythrodiol (16), (-)-epicatechin (17), daucosterol (18), (-)-epipinoresinol (19), and salicylic acid (20). Conclusion: Compounds 1, 2, 5, 6, and 11 are isolated from this plant for the first time, and compounds 4, 7, and 8 are isolated from the plants of Quercus L. for the first time.