A compound of formula I where: Ar 1 is phenyl, pyridinyl, pyridazinyl, pyrimidinyl, pyrazinyl, pyrrolyl, furanyl, thienyl, pyrazolyl, isoxazolyl, isothiazolyl, imidazolyl, oxazolyl, thiazolyl, triazinyl, oxadiazolyl, thiadiazolyl, or benzodioxyl, and is substituted with 1-3 substituents selected from cyano, halo, (C 1-6)alkyl, halo(C 1-6)alkyl, (C 1-6)alkoxy, halo(C 1-6)alkoxy, (C 1-6)alkylthio, and SO 2 R 6; Ar 2 is phenyl, pyridinyl, pyridazinyl, pyrimidinyl, or pyrazinyl, and is substituted with 0-3 substituents selected from from cyano, halo, (C 1-6)alkyl, halo(C 1-6)alkyl, (C 1-6)alkoxy, and halo(C 1-6)alkoxy; Ar 3 is (C 6-12)aryl or heteroaryl, and is substituted with 0-3 substituents selected from cyano, halo, (C 1-6)alkyl, halo(C 1-6)alkyl, hydroxy(C 1-6)alkyl, (C 1-6)alkoxy(C 1-6)alkyl, (NR 1 R 2)(C 1-6)alkyl, (CO 2 R 3)(C 1-6)alkyl, (CONR 4 R 5)(C 1-6)alkyl, (SO 2 R 6)(C 1-6)alkyl, hydroxy, (C 1-6)alkoxy, halo(C 1-6)alkoxy, (C 3-7)cycloalkoxy, NR 1 R 2, CO 2 R 3, CONR 4 R 5, SO 2 R 6, oxo, (C 6-12)aryl, and heteroaryl; wherein heteroaryl means a 5 to 7 membered monocyclic or 8 to 11 membered bicyclic aromatic ring system with 1-5 heteroatoms independently selected from nitrogen, oxygen, and sulfur; R 1 is hydrogen, (C 1-6)alkyl, (C 1-6)alkylcarbonyl, (C 1-6)alkylsulfonyl, or halo(C 1-6)alkylsulfonyl; R 2 is hydrogen or (C 1-6)alkyl; or NR 1 R 2 taken together is selected from azetidinyl, pyrrolidinyl, piperidinyl, piperazinyl, and morpholinyl, and is substituted with 0-3 substituents selected from halo, (C 1-6)alkyl, halo(C 1-6)alkyl, (C 1-6)alkoxy, and halo(C 1-6)alkoxy; and R 3 is (C 1-6)alkyl or halo(C 1-6)alkyl; R 4 is hydrogen, (C 1-6)alkyl, or (R 7 R 8 N)(C 1-6)alkyl; R 5 is hydrogen or (C 1-6)alkyl; or NR 4 R 5 taken together is selected from azetidinyl, pyrrolidinyl, piperidinyl, piperazinyl, and morpholinyl, and is substituted with 0-3 substituents selected from halo, (C 1-6)alkyl, halo(C 1-6)alkyl, (C 1-6)alkoxy, and haloC 1-6)alkoxy; R 6 is (C 1-6)alkyl or R 7 R 8 N; R 7 is hydrogen or (C 1-6)alkyl; R 8 is hydrogen or (C 1-6)alkyl; or NR 7 R 8 taken together is selected from azetidinyl, pyrrolidinyl, piperidinyl, piperazinyl, and morpholinyl, and is substituted with 0-3 substituents selected from halo, (C 1-6)alkyl, halo(C 1-6)alkyl, (C 1-6)alkoxy, and halo(C 1-6)alkoxy; and X is hydrogen, halo, hydroxy, or (C 1-6)alkoxy; or a pharmaceutically acceptable salt thereof. Ar 1 is phenyl, pyridinyl, pyridazinyl, pyrimidinyl, pyrazinyl, pyrrolyl, furanyl, thienyl, pyrazolyl, isoxazolyl, isothiazolyl, imidazolyl, oxazolyl, thiazolyl, triazinyl, oxadiazolyl, thiadiazolyl, or benzodioxyl, and is substituted with 1-3 substituents selected from cyano, halo, (C 1-6)alkyl, halo(C 1-6)alkyl, (C 1-6)alkoxy, halo(C 1-6)alkoxy, (C 1-6)alkylthio, and SO 2 R 6; Ar 2 is phenyl, pyridinyl, pyridazinyl, pyrimidinyl, or pyrazinyl, and is substituted with 0-3 substituents selected from from cyano, halo, (C 1-6)alkyl, halo(C 1-6)alkyl, (C 1-6)alkoxy, and halo(C 1-6)alkoxy; Ar 3 is (C 6-12)aryl or heteroaryl, and is substituted with 0-3 substituents selected from cyano, halo, (C 1-6)alkyl, halo(C 1-6)alkyl, hydroxy(C 1-6)alkyl, (C 1-6)alkoxy(C 1-6)alkyl, (NR 1 R 2)(C 1-6)alkyl, (CO 2 R 3)(C 1-6)alkyl, (CONR 4 R 5)(C 1-6)alkyl, (SO 2 R 6)(C 1-6)alkyl, hydroxy, (C 1-6)alkoxy, halo(C 1-6)alkoxy, (C 3-7)cycloalkoxy, NR 1 R 2, CO 2 R 3, CONR 4 R 5, SO 2 R 6, oxo, (C 6-12)aryl, and heteroaryl; wherein heteroaryl means a 5 to 7 membered monocyclic or 8 to 11 membered bicyclic aromatic ring system with 1-5 heteroatoms independently selected from nitrogen, oxygen, and sulfur; R 1 is hydrogen, (C 1-6)alkyl, (C 1-6)alkylcarbonyl, (C 1-6)alkylsulfonyl, or halo(C 1-6)alkylsulfonyl; R 2 is hydrogen or (C 1-6)alkyl; or NR 1 R 2 taken together is selected from azetidinyl, pyrrolidinyl, piperidinyl, piperazinyl, and morpholinyl, and is substituted with 0-3 substituents selected from halo, (C 1-6)alkyl, halo(C 1-6)alkyl, (C 1-6)alkoxy, and halo(C 1-6)alkoxy; and R 3 is (C 1-6)alkyl or halo(C 1-6)alkyl; R 4 is hydrogen, (C 1-6)alkyl, or (R 7 R 8 N)(C 1-6)alkyl; R 5 is hydrogen or (C 1-6)alkyl; or NR 4 R 5 taken together is selected from azetidinyl, pyrrolidinyl, piperidinyl, piperazinyl, and morpholinyl, and is substituted with 0-3 substituents selected from halo, (C 1-6)alkyl, halo(C 1-6)alkyl, (C 1-6)alkoxy, and haloC 1-6)alkoxy; R 6 is (C 1-6)alkyl or R 7 R 8 N; R 7 is hydrogen or (C 1-6)alkyl; R 8 is hydrogen or (C 1-6)alkyl; or NR 7 R 8 taken together is selected from azetidinyl, pyrrolidinyl, piperidinyl, piperazinyl, and morpholinyl, and is substituted with 0-3 substituents selected from halo, (C 1-6)alkyl, halo(C 1-6)alkyl, (C 1-6)alkoxy, and halo(C 1-6)alkoxy; and X is hydrogen, halo, hydroxy, or (C 1-6)alkoxy; or a pharmaceutically acceptable salt thereof.