Indole alkaloid glycosides from Isatis tinctoria roots

Isatindigoside A and B (1 − 2), two new indole alkaloid glycosides along with five known ones (3 − 7) were obtained from the roots of I. tinctoria. Their structures were determined as isatindigoside A (1), isatindigoside B (2), isatindosulfonicacid A 3-O-β-D-glucopyranoside (3), indole-3-acetonitrile 6-O-β-D-glucopyranoside (4), isatindigobisindoloside A (5), isatindigobisindoloside B (6) isatindigobisindoloside F (7), by physicochemical properties and spectroscopic methods including 1 D, 2 D NMR, IR, HR-ESI-MS data. Nitric oxide (NO) inhibitory activities of all of the isolated compounds (1 − 7) were also evaluated. Compounds 2 and 7 showed inhibitory effects against LPS-stimulated RAW 264.7 cells with IC50 values of 27.6 μM and 18.8 μM, respectively.