Formazan

The formazans are compounds of the general formula [R-N=N-C(R')=N-NH-R"], formally derivatives of formazan [H₂NN=CHN=NH], unknown in free form.^[1]

Formazan dyes are artificial chromogenic products obtained by reduction of tetrazolium salts by dehydrogenases and reductases. They have a variety of colors from dark blue to deep red to orange, depending on the original tetrazolium salt used as the substrate for the reaction.

^ formazans Archived 2022-01-20 at the Wayback Machine. In: Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"). Compiled by A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford (1997). Online version (2019-) created by S. J. Chalk. ISBN 0-9678550-9-8. doi:10.1351/goldbook.

[1] rmazans Archived 2022-01-20 at the Wayback Machine. In: Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"). Compiled by A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford (1997). Online version (2019-) created by S. J. Chalk. ISBN 0-9678550-9-8. doi:10.1351/goldbook.

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