This invention is the okisepin derivative which possesses the histamine receptor competition action which is superior, there are times when useful chemical compound is offered as an anti- histamine medicine. This invention okisepin derivative has powerful histamine receptor competition activity. Furthermore this invention chemical compound at the time of receptor connection testing inside the brain which is prescribed to the mouse orally from the fact that movement characteristic inside the brain which is low is shown, has desirable quality in the point, reduction of the central characteristic side effect of sleepiness and the like. Therefore, as for this invention okisepin derivative they are very useful ones as the anti- histamine medicine which is new the central characteristic side effect of sleepiness and the like is little.本発明は優れたヒスタミン受容体拮抗作用を有するオキセピン誘導体であり、抗ヒスタミン薬として有用な化合物を提供することにある。本発明オキセピン誘導体は強力なヒスタミン受容体拮抗活性を有する。さらに本発明化合物は、マウスに経口投与した脳内受容体結合試験においても低い脳内移行性を示すことから、眠気等の中枢性副作用の軽減という点で好ましい特性を有する。従って、本発明オキセピン誘導体は眠気等の中枢性副作用が少ない新規な抗ヒスタミン薬として非常に有用なものである。