Novel Flavonoids in Dragon's Blood of Daemonorops draco

The three novel methylene bis[flavonoids] 1-3, the novel 2-flavene 4, the new naturally occurring flavan 5, and the new retro-dihydrochalcone 6 were isolated from dragon's blood of Daemonorops draco, together with seven known compounds. The structures were elucidated by extensive 1D- and 2D-NMR spectroscopic analysis.