Chemical basis for the biological activity of imexon and related cyanoaziridines

Bhashyam S Iyengar1, Robert T Dorr, William A Remers

  • 1Arizona Cancer Center and Department of Pharmacology and Toxicology, University of Arizona, Tucson, Arizona 85721, USA.

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The reaction of weakly electrophilic aryldiazonium (also called arenediazonium) salts with highly activated aromatic compounds leads to the formation of products with an —N=N— link, called an azo linkage. This reaction, presented in Figure 1, is known as diazo coupling and occurs without the loss of the nitrogen atoms of the aryldiazonium salt. Highly activated aromatic compounds such as phenols or arylamines favor the diazo coupling reaction. The coupling generally occurs at the para position.
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Aldehydes and Ketones with Amines: Imine and Enamine Formation Overview

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Imines are formed under mildly acidic conditions. A pH of 4.5 is ideal for the reaction.
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