Novel reductase participation in the syn-addition of hydrogen to the CC bond of enones in the cultured cells of Nicotiana tabacum

Abstract

A reductase isolated from cultured cells of Nicotiana tabacum has been characterized and used in the reduction of a CC bond adjacent to a carbonyl group. The stereochemistry of the latter reaction has been investigated by ²H NMR and mass spectroscopy. It was found that the reductase reduces stereospecifically the CC bond of verbenone and carvone by syn addition of hydrogen from the re face at the β-position and the re face at the α-position to the carbonyl group; the hydrogen atoms participating in the enzymatic reduction at the α- and β-positions originate from the medium (H₂O) and the pro-4S hydrogen of NADPH, respectively.