There are three isomers, varying in where the oxygen is positioned in the oxepin heterocycle relative where the benzene is fused to it.

1-Benzoxepin, with the oxygen closest to the benzene, is found in the skeleton of several fungal metabolites.

[1] 2-Benzoxepin skeletons are likewise found in fungal metabolites.

[2] 3-Benzoxepin, with the oxygen furthest from the benzene, is the core of natural products such as perilloxin from Perilla frutescens (variant Acuta)[3] and tenual and tenucarb from Asphodeline tenuior.

This article about a heterocyclic compound is a stub.