A compound of Formula or a salt thereof, wherein: HET is a heteroaryl selected from pyrazole, indole, pyrrolo[2,3-b]pyridine, pyrrolo[2,3-d]pyrimidine, pyrazolo[3,4-b] pyridine, pyrazolo[3,4-d]pyrimidine, or purine, wherein said heteroaryl is substituted with zero or one substituent selected from F, Cl, Br, -OH, -CN, -CH 3, -NH 2, -N(CH 3) 2, -NHCH 2 C(CH 3) 2 OH, -NHC CH 3, -NHCH 2 CH 2 OH, -C NH 2, hydroxypyrrolidine, and pyridazine; R 1 is: (i) C 1-7 alkyl substituted with 1 to 4 substituents independently selected from F, -OH, -OCH 3, -OCH(CH 3) 2, -OC(CH 3) 3, -C NHCH 3, -NH(CH(CH 3) 2), -NHS 2 CH 3, -NHC C(CH 3) 2 OC CH 3, -C NH(tetrahydrothiophene 1,1-dioxide), -OP 2, morpholine, and phenyl substituted with -S 2 NH 2; (ii) bicyclo[2.2.1]heptan-1-ol, tetrahydrobenzo[d]thiazol-2-amine, or 1,3-diazaspiro[4.5]decane-2,4-dione; or (iii) C 3-6 cycloalkyl substituted with 1 to 3 substituents independently selected from F, -OH, -NO 2, -CH 3, -C(CH 3) 2 OH, -C NH(CH 3), -C NH(CD 3), -C NH(CH 2 CH 3), -C NH(cyclopropyl), -NHC CH 3, -NHC OCH 3, -NHS 2 CH 3, -S 2 CH 3, -SCH 3, pyridine, methylimidazole, methylpyrazole, and thiazole; and R 2 is: (i) C 2-6 alkyl substituted with zero to three substituents independently selected from F and -OH; (ii) -(CH 2) 0-3 -R x wherein R x is C 3-6 cycloalkyl, oxetane, tetrahydrofuran, or tetrahydropyran, each substituted with zero to 2 substituents selected from F, -OH, and -CH 3; (iii) adamantane, benzothiazole, or bicyclo[2.2.1]heptan-1-ol; or (iv) phenyl substituted with -OH, -CN, -CH 2 OH, -C(CH 3) 2 OH, -OCH 3, -C NH 2, -C NH(CH 3), -NHC CH 3, -NHS 2 CH 3, -S 2 NH 2, pyrazole, triazole, or methyl tetrazole. HET is a heteroaryl selected from pyrazole, indole, pyrrolo[2,3-b]pyridine, pyrrolo[2,3-d]pyrimidine, pyrazolo[3,4-b] pyridine, pyrazolo[3,4-d]pyrimidine, or purine, wherein said heteroaryl is substituted with zero or one substituent selected from F, Cl, Br, -OH, -CN, -CH 3, -NH 2, -N(CH 3) 2, -NHCH 2 C(CH 3) 2 OH, -NHC CH 3, -NHCH 2 CH 2 OH, -C NH 2, hydroxypyrrolidine, and pyridazine; R 1 is: (i) C 1-7 alkyl substituted with 1 to 4 substituents independently selected from F, -OH, -OCH 3, -OCH(CH 3) 2, -OC(CH 3) 3, -C NHCH 3, -NH(CH(CH 3) 2), -NHS 2 CH 3, -NHC C(CH 3) 2 OC CH 3, -C NH(tetrahydrothiophene 1,1-dioxide), -OP 2, morpholine, and phenyl substituted with -S 2 NH 2; (ii) bicyclo[2.2.1]heptan-1-ol, tetrahydrobenzo[d]thiazol-2-amine, or 1,3-diazaspiro[4.5]decane-2,4-dione; or (iii) C 3-6 cycloalkyl substituted with 1 to 3 substituents independently selected from F, -OH, -NO 2, -CH 3, -C(CH 3) 2 OH, -C NH(CH 3), -C NH(CD 3), -C NH(CH 2 CH 3), -C NH(cyclopropyl), -NHC CH 3, -NHC OCH 3, -NHS 2 CH 3, -S 2 CH 3, -SCH 3, pyridine, methylimidazole, methylpyrazole, and thiazole; and (i) C 1-7 alkyl substituted with 1 to 4 substituents independently selected from F, -OH, -OCH 3, -OCH(CH 3) 2, -OC(CH 3) 3, -C NHCH 3, -NH(CH(CH 3) 2), -NHS 2 CH 3, -NHC C(CH 3) 2 OC CH 3, -C NH(tetrahydrothiophene 1,1-dioxide), -OP 2, morpholine, and phenyl substituted with -S 2 NH 2; (ii) bicyclo[2.2.1]heptan-1-ol, tetrahydrobenzo[d]thiazol-2-amine, or 1,3-diazaspiro[4.5]decane-2,4-dione; or (iii) C 3-6 cycloalkyl substituted with 1 to 3 substituents independently selected from F, -OH, -NO 2, -CH 3, -C(CH 3) 2 OH, -C NH(CH 3), -C NH(CD 3), -C NH(CH 2 CH 3), -C NH(cyclopropyl), -NHC CH 3, -NHC OCH 3, -NHS 2 CH 3, -S 2 CH 3, -SCH 3, pyridine, methylimidazole, methylpyrazole, and thiazole; and R 2 is: (i) C 2-6 alkyl substituted with zero to three substituents independently selected from F and -OH; (ii) -(CH 2) 0-3 -R x wherein R x is C 3-6 cycloalkyl, oxetane, tetrahydrofuran, or tetrahydropyran, each substituted with zero to 2 substituents selected from F, -OH, and -CH 3; (iii) adamantane, benzothiazole, or bicyclo[2.2.1]heptan-1-ol; or (iv) phenyl substituted with -OH, -CN, -CH 2 OH, -C(CH 3) 2 OH, -OCH 3, -C NH 2, -C NH(CH 3), -NHC CH 3, -NHS 2 CH 3, -S 2 NH 2, pyrazole, triazole, or methyl tetrazole. (i) C 2-6 alkyl substituted with zero to three substituents independently selected from F and -OH; (ii) -(CH 2) 0-3 -R x wherein R x is C 3-6 cycloalkyl, oxetane, tetrahydrofuran, or tetrahydropyran, each substituted with zero to 2 substituents selected from F, -OH, and -CH 3; (iii) adamantane, benzothiazole, or bicyclo[2.2.1]heptan-1-ol; or (iv) phenyl substituted with -OH, -CN, -CH 2 OH, -C(CH 3) 2 OH, -OCH 3, -C NH 2, -C NH(CH 3), -NHC CH 3, -NHS 2 CH 3, -S 2 NH 2, pyrazole, triazole, or methyl tetrazole.