NADH dihydronicotinamide adenine

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+... 

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. 

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... 

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. 

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. 

FIGURE 9.28 CVs of GC, EPPG, nondoped CNT, 4.0 atom% N-CNT, and 7.4 N-CNT electrodes in the presence of 2 mM NADH. (Reprinted with permission from Goran, J.M., Favela, C.A., and Stevenson, K.J., Electrochemical oxidation of dihydronicotinamide adenine dinucleotide at nitrogen-doped carbon nanotube electrodes, Anal. Chem., 85,9135-9141. Copyright 2013, American Chanical Society.)... 

Moiroux J, Elving PJ (1980) Adsorption phenomena in the NAD+/NADH oxidation of dihydronicotinamide adenine dinucleotide (NADH). J Am Chan Soc 102 6533-6538... 

Gorton L, Johansson G, Torstensson A. A kinetic study of the reaction between dihydronicotinamide adenine dinucleotide (NADH) and electrode modified by adsorption of l,2-benzophenoxazine-7-one. J Electroanal Chem 1985 196 81-92. 

Cai CX, Xue KH. The effects of concentration and solution pH on the kinetic parameters for the electrocatal)4ic oxidation of dihydronicotinamide adenine dinucleotide (NADH) at... 

The reduction of 5-nitrouracil derivatives 381 has been performed using l-benzyl-l,4-dihydronicotinamide 382 as a reduced nicotinamide adenine dinucleotide (NADH) model <1998H(49)475>, although the same products can also be obtained with sodium borohydride <1976JME1072>. 

The NAD —enzyme complex exhibits absorption regions that characterize protein, adenine and nicotinamide, i.e. in the range 240 to 290 nm. In the NADH—enzyme complex, the dihydronicotinamide part absorbs at 340 nm. 

The dihydronicotinamide ring of NADH fluoresces weakly at 470 nm when excited within its absorption band. The intensity of fluorescence in water is low and can be increased by solution in organic solvents 30) and shifted to shorter wavelengths (330 nm) by cleaving the pyrophosphate bond and thus removing the interaction with adenine (231). The fluorescence is increased on combination with the enzyme [122,2. but can be either enhanced or quenched when a ternary complex forms. 

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