Two new compounds from Paeonia lactiflora.

Two new compounds, namely 5-methyl-4,2',3',5'-tetrahydroxy-4'-methoxy-2-aldehyde biphenyl (1) and 1,8-dioxo-1,8-dihydropyrano[3,4-c]pyran-3,6- dicarboxyl acid, diethyl ester (2), were isolated from the 95% ethanol extract of the roots of Paeonia lactiflora Pall. The structures of 1 and 2 were elucidated by spectroscopic methods, including UV, IR, HR-ESI-MS and extensive 1D and 2D NMR techniques.