Neoflavonoid

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

Structure of the neoflavonoids backbone (neoflavan represented)
Chemical structure of 4-phenylcoumarin (neoflavone backbone).