Two new diprenylated flavanones from Derris laxiflora Benth.

Phytochemical reinvestigation on the whole plants of Derris laxiflora Benth. afforded two new diprenylated flavanones, derriflavanones B and C (1-2), together with thirty-two known compounds, including sixteen flavonoids (3-18), eleven aromatic compounds (19-29), and five chlorophylls (30-34). All known compounds were first isolated from this plant. The structures of these compounds were determined by analysis of the NMR spectroscopy, mass data, IR spectra, UV spectra, optical rotation and by comparison with literature data.