Dihydronicotinamide adenine

Dioxetanes are readily reduced to 1,2-diols (Scheme 30) by lithium aluminum hydride (75CJC1103), thiols (88AG(E)429), and biologically important reductants (89MI 133-02) such as ascorbic acid, tocopherol, dihydronicotinamide adenine dinucleotide (NADH), and riboflavin adenosine diphosphate (FADH2). 

A different approach for utilization of the photoproducts in chemical routes involves the introduction of natural enzymes as catalysts in the photochemical system. In nature, dihydronicotinamide adenine dinucleotide (NADH) and dihydronicotinamide dinucleotide phosphate (NADPH) participate as reducing cofactors in a variety of enzymatic reduction processes. Thus, the development of photochemical NADH and NADPH regeneration cycles is anticipated to allow a variety of reduction processes by inclusion of substrate specific NAD(P)H dependent enzymes. 

The catalytic, asymmetric hydrogenations of alkenes, ketones and imines are important transformations for the synthesis of chiral substrates. Organic dihydropyridine cofactors such as dihydronicotinamide adenine dinucleotide (NADH) are responsible for the enzyme-mediated asymmetric reductions of imines in living systems [86]. A biomimetic alternative to NADH is the Hantzsch dihydropyridine, 97. This simple compound has been an effective hydrogen source for the reductions of ketones and alkenes. A suitable catalyst is required to activate the substrate to hydride addition [87-89]. Recently, two groups have reported, independently, the use of 97 in the presence of a chiral phosphoric acid (68 or 98) catalyst for the asymmetric transfer hydrogenation of imines. 

In addition, the DNPH (2,4-dinitrophenylhydrazine) [38] and NADH (dihydronicotinamide adenine dinucleotide) [36] studies with purified Iso-4 provided the evidence that the 70 Da moiety was a pyruvate derivative (C3H2O2). In the DNPH study, treatment of Iso-4 with acid and 2,4-dinitrophenylhydrazine produced the 2,4-dinitrophenylhydrazone of the pyruvic acid liberated from Iso-4. In the NADH study, the amount of NAD+... 

Moiroux, J., and Elving, P.J. 1978. Effects of adsorption, electrode material, and operational variables on the oxidation of dihydronicotinamide adenine dinucleotide at carbon electrodes. Analytical Chemistry 50, 1056-1062. 

Figure 4.1. The nicotinamide coenzymes, nicotinamide adenine dinucleotide (NAD or NADP+) and dihydronicotinamide adenine dinucleotide (NADH or NADPH). The locations of C(4 ) and C(2 ) are indicated. The groups R and M are important only for binding...

Finally, perhaps an explanation for the beneficial effects of coenzyme A (CoA), malate and pyruvate for the extracellular in vitro growth of P. lophurae found by Trager (1952) and interpreted by Moulder (1962) to neatly explain the shift in pattern of carbohydrate metabolism accompanying liberation of parasites from the host cell. .. (The) lack of CoA in free parasites logically explains the lessened rate of pyruvic acid oxidation via the Krebs cycle. It is difficult to escape the conclusion that the inability of plasmodia to synthesize CoA extracellularly results in extensive dislocations in glucose metabolism, which in turn contribute heavily to the restriction of the malarial parasite to an intracellular habitat is this malate and pyruvate could be linked to the generation of dihydronicotinamide adenine dinucleotide (NADH) for glycolysis, and a CoA deficiency could limit activity in pathways other than the TCA cycle. 

Nicotinamide adenine dinucleotide (NAD and its reduced form dihydronicotinamide adenine dinucleotide (NADH)) as well as nicotinamide adenine dinucleotide phosphate (NADP and its reduced form nicotinamide adenine dinucleotide phosphate hydrogen (NADPH)) are essential co-factors for many dehydrogenases. The presence of NAD was first demonstrated in P. gallinaceum (Speck and Evans, 1945) and later studies showed increased levels of these pyridine nucleotides in P. lophurae, P. berghei and P. falciparum. Trager (1977) reported that high levels of... 

Antiochia, R. Lavagnini, I. Magno, F. Electrocatalytic oxidation of dihydronicotinamide adenine dinucleotide with ferrocene carboxylic acid by diaphorase from Clostridium kluveri. Remarks on the kinetic approaches usually adopted. Ekctroanalysis 1999, 11, 129-133. Sanchez, P. D. Ordieres, A. J. M. Garcia, A. G. Blanco, P. T. Peroxidase ferrocene modified carbon paste electrode as an amperometric sensor for the hydrogen-peroxide assay. Ekctroanalysis 1991, 3, 281—285. 

Samec, Z., Elving, P. J., Anodic Oxidation of Dihydronicotinamide Adenine Dinucleotide at Solid Electrodes Mediation by Surface Species , J. Electroanal. Chem. 144 (1983) 217-234. 

Jaegfeldt, H., Kuwana, T., Johansson, G., Electrochemical Stability of Catechols with a Pyrene Side Chain Strongly Adsorbed on Graphite Electrodes for Catalytic Oxidation of Dihydronicotinamide Adenine Dinucleotide , J. Am. Chem. Soc. 105 (1983) 1805-1814. 

Gorton, L., Johansson, G., Torstensson, A., A Kinetic Study of the Reaction between Dihydronicotinamide Adenine Dinucleotide (NADH) and an Electrode Modified by Adsorption of I,2-Benzophenoxazine-7-One , J. Electroanal. Chem. 196 (1985) 81-92. 

Ph2P(S)CH2PPh2 Ph2P(Se)CH2PPh2 diphosphopyridine nucleotide dihydronicotinamide adenine dinucleotide bis( 1,4-diphenylphosphino)butane bis( 1,2-diphenylphosphino)ethane bis( 1,1 -diphenylphosphino)methane bis( 1,3 -diphenylphosphino)propane diphenyl sulphoxide differential thermal gravimetry... 

The PMEs were investigated for their ability to mediate oxidation of such biologically important analytes as ascorbic acid (AA) and dihydronicotinamide adenine dinucleotide (NADH). Van Koppenhagen and Majda incorporated ferricyanide ions into a film of polyacrylamide and acrylamide/vinylpyridine copolymers on electrode surfaces by ion exchange, and they examined the kinetics of the mediated oxidation of AA by ferricyanide. The mediated reaction occurred at lower anodic potentials (200 mV versus Ag/AgCl) than the corresponding... 

Liu et al. established a colorimetric sensing strategy for dihydronicotinamide adenine dinucleotide (NADH, 34). When 4-mercaptophenylboronic acid (MPBA) is introduced on the surface of AuNPs through Au-S interaction. 

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