Neoflavonoid

Structure of the neoflavonoids backbone (neoflavan represented)

Neoflavonoids are a class of polyphenolic compounds. 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

Chemical structure of 4-phenylcoumarin (neoflavone backbone).

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

• Neoflavones are derived from the 4-phenylcoumarin (or 4-Aryl-coumarin) backbone (C₁₅H₁₂O₂, molar mass : 224.25g/mol, exact mass : 224.083729). The first neoflavone isolated from natural sources in 1951 was calophyllolide from Calophyllum inophyllum seeds. It is also known to found in bark and timber of Sri Lankan endemic plant Mesua thwaitesii.
• Neoflavenes possess the 4-phenylchromen backbone (chemical formula : C₁₅H₁₀O₂, exact mass : 222.0680792). Dalbergichromene, extracted from the stem-bark and heartwood of Dalbergia sissoo, is an example of such compounds

Other examples

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