phenoxazine

chemistry

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July 17, 2026

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Phenoxazine is a crystalline compound with the chemical formula C₁₂H₉NO. It is structurally analogous to phenothiazine, with an oxygen atom replacing the sulfur atom. Phenoxazine is the parent compound for oxazine dyes, such as gallocyanine. It belongs to the class of heterocyclic compounds, which are cyclic compounds containing atoms of at least two different elements in their rings. Specifically, phenoxazine features a six-membered ring system with nitrogen and oxygen heteroatoms. Compounds containing the phenoxazine ring are utilized as biological stains, fabric dyes, and light-emitting materials in dye lasers.12

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heterocyclic compound
Five- and six-membered rings with two or more heteroatoms
The phenoxazine system is a chromophoric (colour-imparting) part of the molecular structures of the naturally occurring actinomycin antibiotics, which are yellow-red in colour. Many polycyclic compounds containing a phenoxazine ring are used as biological stains, fabric dyes, and light-emitting materials in dye lasers (e.g., cresyl violet…
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The phenoxazine system is a chromophoric (colour-imparting) part of the molecular structures of the naturally occurring actinomycin antibiotics, which are yellow-red in colour. Many polycyclic compounds containing a phenoxazine ring are used as biological stains, fabric dyes, and light-emitting materials in dye lasers (e.g., cresyl violet…
Read More