[A new triterpenic acid from the roots of Rosa laevigata].

This study was designed to investigate triterpenoids from the roots of Rosa laevigata Michx. The silica gel column chromatography was used to separate the chemical constituents from the roots of Rosa laevigata Michx. HPLC was used to analyze its purity and chemical constitution. Spectroscopy methods were used to determine their structures. Five constituents were isolated and identified as19α-OH-3β-E-feruloyl corosolic acid (1), 23-hydroxy-tormentic acid (2), 2α, 3β, 19α, 23- tetrahydroxy-12-en-28-oleanolic acid (3), 2α, 3α, 20β- trihydroxyurs-13 (18)-en-28-oic-acid (4), 2α, 3β, 20β-trihydroxyurs-13 (18)-en-28-oic-acid (5). Compound 1 was assigned as a new compound, compounds 4, 5 were obtained from the genus Rosa for the first time.