A new benzaldehyde from aerial part of Rehmannia glutinosa

A new benzaldehyde, 3-hydroxy-4-(4-(2-hydroxyethyl) phenoxy) henzaldehyde(1), together with six known compounds, including isovanillic acid(2), pyrocatechol(3), glutinosalactone A(4), chrysoeriol(5), apigenin(6) and luteolin(7) were isolated from aerial part of Rehmannia glutinosa. The compounds were isolated by macroporous resin, silica gel, Sephadex LH-20 and HPLC chromatographies. The chemical structures of 1-7 were elucidated on the basis of spectral analysis (MS, 1D NMR and 2D NMR).