Disclosed are compounds of formula (I) such as N-(1,3-benzothiazol-2-yl)-2-(4-{ [(4-{ [(2R)-4-(dimethylamino)-I-(phenylsulfanyl)butan-2-yl]amino} -3-nitrophenyl)sulfonyl]carbamoyl} -1,3-thiazol-2-yl)-1,2,3,4-tetrahydroisoquinoline-8-carboxamide which inhibit the activity of anti-apoptotic Bcl-xL proteins. Compositions containing these compounds are suitable for treating diseases during which is expressed anti apoptotic Bcl-xL protein, wherein the diseases includes bladder cancer, brain cancer, breast cancer, bone marrow cancer, cervical cancer, chronic lymphocytic leukemia, colorectal cancer, esophageal cancer, hepatocellular cancer, lymphoblastic leukemia, follicular lymphoma, a lymphoid malignancy ofT-cell or B-cell origin, melanoma, myelogenous leukemia, myeloma, oral cancer, ovarian cancer, non-small cell lung cancer, prostate cancer, small cell lung cancer and spleen cancer.
