Twenty-two species of Scophulariaceae have been found to accumulate flavonoid aglycones externally on their leaves and stems. They belong to the genera Anarrhinum, Antirrhinum, Asarina, Calceolaria, Mimulus, and Odontites. Most of the flavonoids are methylated flavones and flavonols, some with 6-O and/or 8-O-substitution. One of them is the natural isobutyryl ester of a rare flavone.
Wollenweber E, Dörr M, Roitman JN. Epicuticular flavonoids of some Scrophulariaceae.. Zeitschrift fur Naturforschung. C, Journal of biosciences. 2000; 55(1-2):5-9.
Zeitschrift fur Naturforschung. C, Journal of biosciences