Leaf Gland Flavonoids in Comptonia peregrina and Myrica pensylvanica (Myricaceae).

Natural products are formed in some Myricaceae by secretory glands on leaves, young twigs, and fruits. Leaf glands of Myrica pensylvanica and Comptonia peregrina produce flavonoid aglycones along with terpenoid material. This is the first study on exudate flavonoids of the two species. In M. pensylvanica rare C-methylated flavonones and chalcones, such as cryptostrobin, desmethoxymatteucinol, aurentiacin, and myrigalon-D, are the major constituents. In C. peregrina chrysin, galangin, pinocembrin, and their methyl ethers are dominant. They are accompanied by some of the C-methyl flavonoids found in M. pensylvanica. A novel natural flavanone, 7-hydroxy-5-methoxy-6-C-methyl flavanone (comptonin) was isolated from C. peregrina, where it was encountered along with trace amounts of the corresponding 2',4'-dihydroxy-6'-methoxy-5'-C-methyl chalcone.