PROBLEM TO BE SOLVED: To provide a small molecule inhibitor of phosphatidyl inositol 3-kinase (PI3K) relating to many malignant diseases such as ovarian cancer, cervical cancer, breast cancer, colon cancer, rectal cancer and glioblastoma.SOLUTION: There is provided a quinoxaline sulfonamide compound represented by the formula (I).【課題】卵巣癌、子宮頸癌、乳癌、大腸癌、直腸癌、及び膠芽細胞腫のような多くの悪性疾患に関連するホスファチジルイノシトール3-キナーゼ(PI3K)の小分子インヒビターの提供。【解決手段】式(I)で表されるキノキサリンスルホンアミド化合物。【選択図】なし