Phenoxathiin (dibenzooxathiane) C12H8OS is a heterocyclic compound of molecular weight 200.25632 g/mol with the CAS Registry Number 262-20-4.

[2] Diphenyl ether is a starting material in the production of phenoxathiin via the Ferrario reaction.

[3] Phenoxathiin is used in polyamide and polyimide production.

[4]