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Updated: Jul 20, 2026

Biosynthesis of a Flavonol from a Flavanone by Establishing a One-pot Bienzymatic Cascade
Published on: August 14, 2019
Multiple hydride reduction pathways in isoflavonoids
Auli K Salakka1, Tuija H Jokela, Kristiina Wähälä
1Department of Chemistry, Laboratory of Organic Chemistry, P.O. Box 55, FIN-00014 University of Helsinki, Finland. auli.salakka@kemira.com
Background:
Isoflavonoids are of interest owing to their appearance in metabolic pathways of isoflavones, and their estrogenic and other physiological properties, making them promising lead compounds for drug design.
Results:
The reduction of isoflavones by various hydride reagents occurs by a 1,4-pathway in contrast to ordinary beta-alkoxy-alpha,beta-unsaturated ketones. Isoflavan-4-ones, cis- and trans-isoflavan-4-ols, alpha-methyldeoxybenzoins or 1,2-diphenylprop-2-en-1-ols are obtained depending on the hydride reagent, mostly in good yields. The stereoselective reduction of isoflavan-4-ones is also discussed.
Conclusion:
The work described in this paper shows that most structural types of reduced isoflavonoids are now reliably available in satisfactory or good yields by hydride reductions to be used as authentic reference compounds in analytical and biological studies.
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