Heteroaryl substituted aminopyridine compounds

A compound of Formula (I)

• or a salt thereof, wherein:
• HET is a heteroaryl selected from oxazolyl, pyrazolyl, imidazo[1,2-b]pyridazin-3-yl, and pyrazolo[1,5-a]pyrimidin-3-yl, wherein said heteroaryl is attached to the pyridinyl group in the compound of Formula (I) by a carbon ring atom in the heteroaryl and wherein said heteroaryl is substituted with zero to 2 Rb;
• each Rb is independently selected from H, F, Cl, —CN, —NH2, C1-3 alkyl, C1-2 fluoroalkyl, C1-3 alkoxy, C3-6 cycloalkyl, —NH(C1-3 alkyl), —NH(C1-4 hydroxyalkyl), cyanophenyl, pyridinyl, and hydroxypyrrolidinyl;
• R1 is:
• (i) C3-6 alkyl substituted with 1 to 4 substituents independently selected from F, —CN, —OH, —OCH3, —OCD3, —NHC(O)(C1-3 alkyl), —S(O)2(C1-3 alkyl), and C1-2 fluoroalkoxy;
• (ii) —(CRyRy)1-3Rx or —(CH2)1-3C(O)Rx, wherein Rx is phenyl, oxetanyl, tetrahydropyranyl, morpholinyl, piperidinyl, imidazolyl, pyridinyl, thiophenyl, or C4-6 cycloalkyl, each substituted with zero to 3 substituents independently selected from F, Cl, —OH, C1-3 alkyl, C1-2 alkoxy, and —S(O)2NH2;
• (iii) C4-6 cycloalkyl substituted with zero to 2 substituents independently selected from —OH, C1-4 hydroxyalkyl, C1-3 alkoxy, —(CH2)1-3O(C1-3 alkyl), —C(O)NH(C1-4 alkyl), —C(O)NH(C3-6 cycloalkyl), —N(C1-3 alkyl)2, —NHC(O)(C1-3 alkyl), —NHC(O)O(C1-3 alkyl), and —NHC(O)(C1-4 hydroxyalkyl);
• (iv) tetrahydrofuranyl, tetrahydropyranyl, piperidinyl, piperazinyl, pyrrolyl, pyrazolyl, imidazolyl, or triazolyl, each substituted with zero to 2 substituents independently selected from C1-4 hydroxyalkyl, —S(O)2(C1-3 alkyl), —CH2C(O)NH(C1-3 alkyl), —CH2C(O)NH(C1-6 hydroxyalkyl), —CH2C(O)NH(C1-6 fluoroalkyl), and —CH2C(O)NH(C1-6 hydroxy-fluoroalkyl);
• or
• (v) 1-oxa-7-azaspiro[3.5]nonanyl;
• each Ry is independently H, F, or —OH;
• and
• R3 is:
• (i) C2-5 alkyl, C2-5 fluoroalkyl, C2-5 hydroxyalkyl, —(CH2)1-3Rz, —CH(CH3)Rz, or —CH(CH2OH)CH2Rz, wherein Rz is C4-6 cycloalkyl, oxetanyl, tetrahydrofuranyl, tetrahydropyranyl, or phenyl, each substituted with zero to 1 substituent selected from —OH and —CH3;
• (ii) C3-6 cycloalkyl substituted with zero to 3 substituents independently selected from F, Cl, —CN, —OH, C1-3 alkyl, C1-3 fluoroalkyl, C1-4 hydroxyalkyl, C1-4 alkoxy, —C(O)NH2, —C(O)NH(C1-3 alkyl), and —C(O)(C1-3 fluoroalkyl);
• (iii) oxetanyl, tetrahydrofuranyl, tetrahydropyranyl, pyrrolidinyl, piperidinyl, pyrazolyl, thiazolyl, bicyclo[1.1.1]pentanyl, bicyclo[2.2.1]heptanyl, or 4,5,6,7-tetrahydropyrazolo[1,5-a]pyrazinyl, each substituted with zero to 2 substituents independently selected from F, —OH, C1-4 alkyl, C1-3 hydroxyalkyl, C1-4 fluoroalkyl, —CH2(C3-6 cycloalkyl), —(CH2)1-3O(C1-3 alkyl), —C(O)(C1-3 fluoroalkyl), —S(O)2(C1-3 alkyl), C3-6 cycloalkyl, C3-6 fluorocycloalkyl, oxetanyl, tetrahydrofuranyl, tetrahydropyranyl, pyrimidinyl, fluoropyrimidinyl, and methoxypyrimidinyl;
• or
• (iv) phenyl substituted with zero to 3 substituents independently selected from F, Cl, —CN, —OH, —C(O)NH2, —C(O)NH(C1-3 alkyl), and —C(O)(C1-3 fluoroalkyl).