Synthesis and Structure of Flavan-4-ols and 4-Methoxyflavans as New Potential Anticancer Drugs

Reduction of a series of substituted flavanones afforded synthetic access to flavan-4-ols and was followed for some of them by an SN2-type acid-catalysis in methanol to provide 4-methoxyflavans. The stereochemistry of these compounds was established by 1H and 13C NMR data. Flavan-4-ols and 4-methoxyflavans have been resolved into enantiomers which are being evaluated as anticancer drugs.