PROBLEM TO BE SOLVED: To provide a novel phosphorus substituted-quinoxaline-type piperidine compound that has affinity to opioid receptor-like (ORL-1) receptor, and is effective in the treatment of chronical and acute pains.SOLUTION: Provided are: a phosphorus substituted-quinoxaline-type piperidine compound represented by the following formula, and a pharmaceutically acceptable derivative thereof; a composition containing an effective amount of a phosphorus-substituted quinoxaline-type piperidine compound; and a method for treating or preventing a pain or the like by administering an effective amount of a phosphorus-substituted quinoxaline-type piperidine compound.SELECTED DRAWING: None【課題】オピオイド受容体様(ORL-1)受容体に親和性を有し、慢性・急性疼痛の治療に有効な新規なリン置換キノキサリンタイプピペリジン化合物の提供。【解決手段】下式で例示されるリン置換キノキサリンタイプピペリジン化合物及びその製薬上許容される誘導体、有効量のリン置換キノキサリンタイプピペリジン化合物を含有する組成物、及び有効量のリン置換キノキサリンタイプピペリジン化合物を投与する、疼痛等を治療又は予防する方法。【選択図】なし