Neoflavonoids are a class of polyphenolic compounds.
[1] While flavonoids (in the narrow sense) have the 2-phenylchromen-4-one backbone, neoflavonoids have the 4-phenylchromen backbone with no hydroxyl group substitution at position 2.
Neoflavonoids include 4-arylcoumarins (neoflavones), 4-arylchromanes, dalbergiones and dalbergiquinols.
The dictionary definition of neoflavonoid at Wiktionary