A new alkaloids isolated from tetraploidy Banlangen

AimTo investigate the chemical constituents of tetraploidy Banlangen (Isatis indigotica Fort.). MethodsCompounds were separated by chromatography on silica gel. Their structures were determined by spectral analysis and chemical evidence. ResultsThree compounds were isolated. Their structures were identified as (E)-2-［(3′-indole) cyanomethylene］-3-indolinone (I), 2-(4-hydroxy-3-methoxy-phenyl)-4-［(4-hydroxy-3-methoxy-phenyl)-methyl］-3-hydroxymethyl-tetrahydro-furan (II) and 2-methoxy-4-［tetrahydro-4-［(4-hydroxy-3-methoxy-phenyl)-methyl］-3-hydroxymethyl-2-furanyl］phenyl-1-O-β-D-glucopyranoside (III). ConclusionCompound I is a new compound.