Two very unusual macrocyclic flavonoids from the water lily Nymphaea lotus

Three novel flavonols, myricetin-3′-O-(6″-p-coumaroyl)glucoside and two epimeric macrocyclic derivatives, as well as the known myricetin-3-O-rhamnoside and pentagalloyl glucose, have been isolated from the wild water lily Nymphaea lotus L. and identified using 2D NMR. This is the first report of such a macrocycle from any source.