Indole alkaloids from the roots of Isatis indigotica and their inhibitory effects on nitric oxide production

Abstract

Three rare indole-2-S-glycosides, indole-3-acetonitrile-2-S-β-D-glucopyranoside (1), indole-3-acetonitrile-4-methoxy-2-S-β-D-glucopyranoside (2) and N-methoxy-indole-3-acetonitrile-2-S-β-D-glucopyranoside (3), together with 11 known indole alkaloids were isolated from the roots of Isatis indigotica Fort. (Cruciferae). The structures of 1-3 were elucidated on the basis of mass spectrometry and extensive 1D and 2D NMR spectroscopy. All of the isolated compounds were tested for inhibitory activity against LPS-induced nitric oxide production in RAW 264.7 macrophages. A plausible biosynthesis pathway of 1-3 is also proposed.

Keywords: 1-Methoxy-indole-3-acetonitrile (PubChem CID: 11954881); 3-Indoleacetic acid (PubChem CID: 802); 3-Indoleformic acid (PubChem CID: 69867); Anti-inflammatory activity; Arvelexin (PubChem CID: 119406); Indole alkaloids; Indole-2-S-glycosides; Indole-3-acetonitrile (PubChem CID: 351795); Isatis indigotica.