AN ARTIFICIAL REDOX COENZYME BASED ON A TRIAZINE DYE TEMPLATE

A series of nicotinamide-containing compounds based on the structure o f a triazine dye, C.l. Reactive Blue 2, which is known to interact at the coenzyme-binding sites of several NAD(P)(H)-dependent dehydrogenas es,(1,2) were designed, synthesized, and characterized. The preparatio n of these compounds is described. Reduction of the coenzyme mimics wi th sodium borohydride led to an increase in absorption at 356 nn, anal ogous to the behavior of the natural coenzyme, NAD(+).(3) When incubat ed with horse liver alcohol dehydrogenase and ethanol at 25 degrees C and pH 9.0, one of the mimics, Blue N-3, was converted into a new comp ound with an increased absorption at 356 nm and an R(f) value on thin- layer chromatography identical to that of the reduced form produced by treatment with sodium borohydride. The oxidized and reduced forms of Blue N-3 could be separated by reverse-phase ion pair high-performance liquid chromatography. This technique could be used to measure the ex tent of Blue N-3 reduction: Approximately 90 turnovers were calculated for each enzyme active site over a 48-h period. Gas chromatography an alysis suggested that ethanol was simultaneously converted to acetalde hyde. Blue N-3 represents the first example of a new generation of pot entially inexpensive, stable, and active biomimetic redox coenzymes.