Nicotinamideadenine dinucleotide

Reduced nicotinamide-adenine dinucleotide (NADH) plays a vital role in the reduction of oxygen in the respiratory chain [139]. The biological activity of NADH and oxidized nicotinamideadenine dinucleotide (NAD ) is based on the ability of the nicotinamide group to undergo reversible oxidation-reduction reactions, where a hydride equivalent transfers between a pyridine nucleus in the coenzymes and a substrate (Scheme 29a). The prototype of the reaction is formulated by a simple process where a hydride equivalent transfers from an allylic position to an unsaturated bond (Scheme 29b). No bonds form between the n bonds where electrons delocalize or where the frontier orbitals localize. The simplified formula can be compared with the ene reaction of propene (Scheme 29c), where a bond forms between the n bonds. 

The procedure involves precolumn oxidation of formate with formate dehydrogenase which is accompanied by a corresponding reduction of p-nicotinamideadenine dinucleotide (P(NAD)+) to reduced P-nicotinamide dinucleotide (ie P NADH). The latter is quantified by high performance liquid chromatography. See also Table 4.1. 

SoKAL, J. A., and L. Klyszejko-Stefanowics Nicotinamideadenine dinucleotides (NAD) in acute poisoning with some toxic agents (In Polish). Lodz Tow. Nauk., Pr. Wydz. 112, (1972). 

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