Chemical constituents in leaves of Morus atropurpurea and their α-glucosidase activity / 中草药

ABSTRACT

Objective: To study the chemical constituents in the leaves of Morus atropurpurea and their biological activity. Methods: The chemical constituents were isolated by silica gel, ODS, Sephadex LH-20 column chromatographies, as well as HPLC. Their structures were elucidated on the basis of physicochemical properties and spectral analysis. The inhibitory effect of the compounds on α-glucosidase was tested by pNP method. Results: Eighteen compounds were isolated from the leaves of M. atropurpurea. Their structures were identified as 1-deoxynojirinycin (1), fagomine (2), cytidine (3), 2-(1', 2', 3', 4'-tetrahydroxybutyl)-5-(2″, 3″, 4″-trihydroxybutyl)-pyrazine (4), 2-(1', 2', 3', 4'-tetrahydroxybutyl)-6-(2″, 3″, 4″-trihydroxybutyl)-pyrazine (5), 2-(1', 2', 3', 4'-tetrahydroxybutyl)-5-(1″, 2″, 3″, 4″-tetrahydroxybutyl)-pyrazine (6), quercetin 3-O-β-D-glucopyranoside (7), kaempferol 3-O-β- D-glucopyranoside (8), kaempferol 3-O-β-rutinoside (9), cichorioside (10), roseoside (11), phytol (12), umbelliferone (13), 1H-indole-3-aldehyde (14), ethyl trans-caffeate (15), sucrose (16), β-sitosterol (17), and daucosterol (18). Conclusion: Compounds 5, 6, 14, and 15 are isolated from the plants of Morus Stapf. for the first time, and compounds 3, 4, 7-13, and 16 are firstly reported from M. atropurpurea. Compounds 1-6 display the potential inhibitory activities on α-glucosidase.