Activation of nitrofurazone by azoreductases: multiple activities in one enzyme

Ali Ryan1, Elise Kaplan, Nicola Laurieri

  • 1Pharmacology Department, University of Oxford, OX1 3QT.

Scientific Reports
|February 23, 2012
PubMed

Related Concept Videos

Phase I Reactions: Reductive Reactions01:27

Phase I Reactions: Reductive Reactions

Phase I biotransformation reductive reactions are chemical processes that modify drugs by introducing or revealing polar functional groups via reduction. Enzymes called reductases catalyze these reactions, playing a pivotal role in drug metabolism by transforming lipophilic drugs into more polar, water-soluble metabolites for easy excretion. An essential type of reductive reaction is the carbonyl group reduction, where aldehydes and ketones are reduced to alcohols. An example is the...
Aryldiazonium Salts to Azo Dyes: Diazo Coupling01:11

Aryldiazonium Salts to Azo Dyes: Diazo Coupling

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.
Preparation of Amines: Reduction of Oximes and Nitro Compounds01:29

Preparation of Amines: Reduction of Oximes and Nitro Compounds

Oximes can be reduced to primary amines using catalytic hydrogenation, hydride reduction, or sodium metal reduction. The reduction of aliphatic and aromatic nitro compounds to primary amines takes place by either catalytic hydrogenation or by using active metals like Fe, Zn, and Sn in the presence of an acid.
Though catalytic hydrogenation can reduce nitrobenzenes, the reduction is nonselective in the presence of other functional groups. For instance, if nitrobenzene contains an aldehyde group,...
2° Amines to N-Nitrosamines: Reaction with NaNO201:20

2° Amines to N-Nitrosamines: Reaction with NaNO2

Secondary amines react with nitrous acid to form N-nitrosamines, as depicted in Figure 1. Nitrous acid, a weak and unstable acid, is formed in situ from an aqueous solution of sodium nitrite and strong acids, such as hydrochloric acid or sulfuric acid, in cold conditions. In the presence of an acid, the nitrous acid gets protonated. The subsequent loss of water results in the formation of the electrophile known as nitrosonium ion.
Nitrosation of Enols01:19

Nitrosation of Enols

The nitrosation reaction is one of the methods of preparing 1,2-diketones. The enol tautomer of the starting ketone reacts with sodium nitrite in hydrochloric acid, generating the 1,2-diketone after hydrolysis.
1° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Mechanism01:37

1° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Mechanism

Nitrous acid is a relatively weak and unstable acid prepared in situ by the reaction of sodium nitrite and cold, dilute hydrochloric acid. In an acidic solution, the nitrous acid undergoes protonation when it loses water to form a nitrosonium ion—an electrophile. Nitrous acid reacts with primary amines to give diazonium salts. The reaction is called diazotization of primary amines.