Abstract: Compounds of formula (1a) and pharmaceutically acceptable salts, solvates, and hydrates thereof and related methods of modulatin perforin activity on a cell: wherein Ring A is selected from a 6-10 membered aryl, 5-6 membered cycloalkyi, 5-6 membered heteroaryl or 5-6 membered heterocyclyl, wherein the heteroaryl and heterocyclyl rings comprise at least one heteroatom selected from N, O or S; and wherein the aryl, cycloalkyi, heteroaryl or heterocyclyl rings are optionally substituted with 1 to 3 substituents selected from halo, nitro, —C1-Cealkyl, —C1-Ceaminoalkyl, —C1-C6hydroxyalkyl, -haloC1-C6alkyl, —C1-C6alkoxyl, -haloC1—C<aIkoxyl, heteroaryl, aryl, hydroxyl, —C(0)Ci-C6alkyl, —OC(0)Ci-C6alkyl, —CH2OC(O)CrC6alkyl, —C(O)OC1, —C6alkyI, —NHC(O)C1, —C6alkyl, —NHS(O)2C1-C6alkyl, —S(O)2C1-C6alkyl, —S(O)2NH2, and —C(O)NJJ; Ring B is a 6-10 membered arylene or a 5-6 membered heteroarylene comprising at least one heteroatom selected from N, 0 or S; and wherein the aryl or heteroaryl is optionally, substituted wit
