RESUMO
Objective: To study the chemical constituents from Swertia macrosperma. Methods: HPLC, column chromatography, and recrystallization techniques were used for the separation and purification of the compounds. Their structures were elucidated by physiochemical properties and spectral analyses. The inhibitory activity against tobacco mosaic virus (TMV) was screened by half-leaf blight spot assay. Results: Eight compounds were isolated from S. macrosperma and their structures were identified as 9, 10-dihydroxyl-sweroside (1), 3'-O-(3-hydroxybenzoyl)-swertiamarin (2), mangiferin (3), 1-O-β-glucopyranosyl-2, 6, 8-trihydroxyl-xanthone (4), campestroside (5), bellidifolin (6), 4, 4'-dihydroxy-Z-stilbene (7), and 4, 4'-dihydroxy-E-stilbene (8). Conclusion: Compound 1 is a new compound named macrospermaoside A, and exhibits weak anti-TMV activity. Compounds 2, 7, and 8 are isolated from the plants of this genus for the first time.