The flavan-4-ols (3-deoxyflavonoids) are

flavone Flavone is an organic compound with the formula . A white solid, flavone is a derivative of chromone with a phenyl (Ph) substituent adjacent to the ether group. The compound is of little direct practical importance, but susbstituted derivatives, t ...

-derived

alcohol Alcohol most commonly refers to: * Alcohol (chemistry), an organic compound in which a hydroxyl group is bound to a carbon atom * Alcohol (drug), an intoxicant found in alcoholic drinks Alcohol may also refer to: Chemicals * Ethanol, one of sev ...

s and a family of flavonoids. Flavan-4-ols are colorless precursor compounds that polymerize to form red

phlobaphene Phlobaphenes (or phlobaphens, CAS No.:71663-19-9) are reddish, alcohol-soluble and water-insoluble phenolic substances. They can be extracted from plants, or be the result from treatment of tannin extracts with mineral acids (tanner's red). The nam ...

pigments. They can be found in the sorghum. Glycosides (abacopterins A, B, C and D together with triphyllin A and 6,8-dimethyl-7-hydroxy-4‘-methoxyanthocyanidin-5-O-β-d-glucopyranoside) can be isolated from a

methanol Methanol (also called methyl alcohol and wood spirit, amongst other names) is an organic chemical and the simplest aliphatic alcohol, with the formula C H3 O H (a methyl group linked to a hydroxyl group, often abbreviated as MeOH). It is a ...

extract of the rhizomes of ''

Abacopteris penangiana ''Menisciopsis penangiana'' is a fern species in the genus '' Menisciopsis''. It has many synonyms, including ''Abacopteris penangiana'' and ''Pronephrium penangianum''. Flavan-4-ols glycosides, abacopterins A, B, C and D together with tri ...

''.

Known flavan-4-ols

Apiforol Apiforol is a chemical compound belonging to the flavan-4ol class of flavonoids. Metabolism Flavanone 4-reductase is an enzyme transforming naringenin into apiforol. This enzyme can be found in ''Columnea hybrida'', in ''Malus domestica'', in ''P ...

Luteoforol Luteoforol is a chemical compound belonging to the flavan-4-ol class of flavonoids. Luteoforol is induced in pome In botany, a pome is a type of fruit produced by flowering plants in the subtribe Malinae of the family Rosaceae. Well-known pome ...

Metabolism

Flavanone 4-reductase In enzymology, a flavanone 4-reductase () is an enzyme that catalyzes the chemical reaction :(2S)-flavan-4-ol + NADP+ \rightleftharpoons (2S)-flavanone + NADPH + H+ Thus, the two substrates of this enzyme are (2S)-flavan-4-ol and NADP+, wher ...

is an enzyme that uses (2''S'')-flavan-4-ol and NADP⁺ to produce (2''S'')-

flavanone The flavanones, a type of flavonoids, are various aromatic, colorless ketones derived from flavone that often occur in plants as glycosides. List of flavanones * Blumeatin * Butin * Eriodictyol * Hesperetin * Hesperidin * Homoeriodictyol * Iso ...

, NADPH, and H⁺.

Spectral data

These compounds have absorption maxima of 564 nm.

References

{{flavan-4ol