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.

Types

Neoflavonoids include 4-arylcoumarins (neoflavones), 4-arylchromanes, dalbergiones and dalbergiquinols.

• Neoflavones^[1] are derived from the 4-phenylcoumarin (or 4-aryl-coumarin) backbone (C₁₅H₁₂O₂).^[2] The first neoflavone isolated from natural sources was calophyllolide from Calophyllum inophyllum seeds (1951).^[3] It is also found in the bark and timber of the plant Mesua thwaitesii, endemic to Sri Lanka.^[4]
• Neoflavenes possess the 4-phenylchromen backbone (C₁₅H₁₀O₂). Dalbergichromene, extracted from the stem-bark and heartwood of Dalbergia sissoo, is an example of such compounds^[5]

Other examples

• Coutareagenin (5-hydroxy-7-methoxy-4-(3,4-dihydroxyphenyl)-2H-benzo-1-pyran-2-on) found in Hintonia latiflora^[6]
• Dalbergin
• Nivetin isolated from Echinops niveus^[7]

References