ABSTRACT
This chapter focuses on the syntheses and properties of 5-deazaflavin derivatives from the viewpoints of synthetic organic chemistry. Polymers containing 5-deazaflavins as functional groups have been made through binding a polystyrene to the 3-position of 5-deazaflavins by a methylene linkage. Amphiphilic flavin (3-methyl-10-dodecylflavin) and 5-deazaflavin (3-methyl-10-dodecyl-5-deazaflavin) form micelle-like aggregates in aqueous solution to cause the decrease of their redox reactivities. However when the aggregates are dissolved in the micelle phase, the redox reactivities are enhanced. It was found that the reduction of carbonyl substrates by 1,5-dihydro-5-deazaflavin is automatically recycled in formic acid. α,β-Unsaturated carbonyl compounds can generally be reduced by hydride ion to give either α,β-unsaturated alcohols or α,β-saturated carbonyl compounds. The stereoselective nonenzymatic reduction of carbonyl groups by the dihydronicotinamide having chiral substituents, as NAD(P)H models, have been widely investigated, and the results have made an important contribution to asymmetrical synthesis.
