Problem to be solved: to provide a cytotoxic novel benzodiazepine compound useful for the treatment of various cell proliferative diseases, and a combination of the combination of the compound and the cell binding agent such as the antibody.A cytotoxic benzodiazepine dimer compound having a reactive group covalently associated with a cell binding agent (CBA) represented by the following compound.(y is h, etc.)No selection【課題】毒性が少なく、様々な細胞増殖性疾患の治療に有用な細胞障害性新規ベンゾジアゼピン化合物、及び前記化合物と抗体等の細胞結合剤が共有結合した複合体の提供。【解決手段】下記化合物に代表される、細胞結合剤（ＣＢＡ）と共有結合可能な反応性基を分子内に有する細胞傷害性ベンゾジアゼピン二量体化合物。（ＹはＨ等）【選択図】なし
