Phenazine

Phenazine (C₁₂H₈N₂ or C₆H₄N₂C₆H₄), also called azophenylene, dibenzo-p-diazine, dibenzopyrazine, and acridizine, is a dibenzo dyestuffs, such as the eurhodines, toluylene red, indulines and safranines.

Organic synthesis

A classic method for the synthesis of phenazine is the reaction of nitrobenzene and aniline in the Wohl-Aue reaction (1901). Other methods are known.

• Phenazene may be obtained by distilling the salt of azobenzoate
• by passing aniline vapor over lead oxide
• or by the oxidation of dihydrophenazine, which is prepared by heating o-phenylenediamine.
• It is also formed when ortho-aminodiphenylamine is distilled over lead peroxide.

Phenazine Sulfuric acid dissolves it, forming a deep-red solution.

Derivatives

• The more complex phenazines, such as the naphthophenazines, naphthazines and naphthotolazines, may be prepared by condensing acids.
• If alkyl or aryl-ortho-diamines be used, azonium fluorescence.
• The hydrochloric acid the amino group is replaced by the hydroxyl group and the phenolic eurhodols are produced.

diaminophenazine

Phenazine Natural Products

Many phenazine compounds are found in nature and are produced by bacteria such as Pseudomonas spp., Streptomyces spp., and Pantoea agglomerans. These phenazine natural products have been implicated in the virulence and competitive fitness of producing organisms. For example, the phenazine pyocyanin produced by Pseudomonas aeruginosa contributes to its ability to colonise the lungs of cystic fibrosis patients. Similarly, phenazine-1-carboxylic acid, produced by a number of Pseudomonas, increases survival in soil environments and has been shown to be essential for the biological control activity of certain strains ^{[2] [3]}.

Phenazine Biosynthesis

Phenazine biosynthesis branches off the biological activities.

References

This article incorporates text from the Encyclopædia Britannica Eleventh Edition, a publication now in the public domain.