University Chemistry ›› 2020, Vol. 35 ›› Issue (12): 247-260.doi: 10.3866/PKU.DXHX202006022

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Incorrect Interpretations from Biochemical Textbooks for 44 Years in the Case of Valence of Nitrogen Atom in Pyridine Ring

Kun Gao()   

  • Received:2020-06-04 Accepted:2020-08-02 Published:2020-09-01
  • Contact: Kun Gao


Understanding redox reactions in reaction of nicotinamide adenine dinucleotide (NAD+) and nicotinamide adenine dinucleotide phosphate (NADP+) requires a clear grasp of the textbook content. The reactions in nicotinamide coenzymes with reduced and oxidized forms have been compared in various biochemistry textbooks. Incorrect interpretations usually emphasize the valence changes that at nitrogen in the pyridine ring of a nicotinamide from +5 to +3. Actually, the valence of nitrogen in pyridine ring is -3. We have gathered shreds of evidences and provide here possible suggestions and caution for readers and instructors.

Key words: Nicotinamide adenine dinucleotide, Nicotinamide adenine dinucleotide phosphate, Oxidation and reduction, Valence


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