Pyradazine compounds as GSK-3 inhibitors

A compound of Formula (I):

• or a salt thereof, wherein
• D is N;
• R1 is phenyl, where said phenyl may be optionally substituted one or more times with C1-C6 alkyl, C1-C6 alkoxy, halogen, or C1-C6 haloalkyl,
• a is 1 or 2;
• y is 0, 1, or 2;
• R2 is hydrogen, C1-C6 alkyl, C1-C6 alkenyl, C1-C6 alkynyl, C1-C6 haloalkyl, C3-C7 cycloalkyl, halogen, tetrahydrofuranyl, pyranyl, 1,4-dioxanyl, 1,3-dioxanyl, piperidinyl, pyrrolidinyl, morpholinyl, tetrahydrothiopyranyl, tetrahydrothiophenyl, aryl, furanyl, thiophenyl, pyrrolyl, imidazolyl, pyrazolyl, triazolyl, tetrazolyl, thiazolyl, oxazolyl, isoxazolyl, oxadiazolyl, thiadiazolyl, isothiazolyl, pyridinyl, pyrazinyl, pyrimidinyl, quinolinyl, isoquinolinyl, benzofuranyl, benzothiophenyl, indolyl, indazolyl, cyano, azido, nitro, —OR8, —OR6R8, —R6R7, —R6R″, S(O)yR7, —C(O)R7, —C(O)OR7,—C(O)NR4R5, —NR′(C═NR4)NR4R5, —OC(O)NR4R5, —OC(O)OR7, —C(═NR4)NR4R5, —NR4R5, —OC(O)R7, or —NR7C(O)R7;
• R3 is -(Q)p-(Q1)
• where
• Q is O, N(R8) or S(O)y,
• p is 0 or 1,
• y is 0, 1, or 2, and
• Q1 is C1-C6alkyl, C3-C7cycloalkyl, C1-C6haloalkyl, aryl, aryl substituted with —C(O)N(H)R6NR4R5 or —OC(H)(OH)R6NR4R5, furanyl, thiophenyl, pyrrolyl, imidazolyl, pyrazolyl, triazolyl, tetrazolyl, thiazolyl, oxazolyl, isoxazolyl, oxadiazolyl, thiadiazolyl, isothiazolyl, pyridinyl, pyridazinyl, pyrazinyl, pyrimidinyl, quinolinyl, isoquinolinyl, benzofuranyl, benzothiophenyl, indolyl, indazolyl, aralkyl, or —R6NR4R5;
• R4 and R5 are independently hydrogen, C1-C3 alkyl, C3-C7 cycloalkyl, or R4 and R5 together with the nitrogen atom to which they are bound form piperidinyl, pyrrolidinyl, morpholinyl, or tetrahydrothiophenyl;
• R6 is alkylene, arylene, furan-2,5-diyl, thiophene-2,4-diyl, 1,3,4-oxadiazole-2,5-diyl, 1,3,4-thiadiazole-2,5-diyl, 1,3-thiazole-2,4-diyl, 1,3,4-thiazole-2,5-diyl, pyridine-2,4-diyl, pyridine-2,3-diyl, pyridine-2,5-diyl, pyrimidine-2,4-diyl, quinoline-2,3-diyl, cycloalkylene, alkenylene, cycloalkenylene, or alkynylene;
• R7 is hydrogen, C1-C6alkyl, C1-C6alkenyl, C1-C6alkynyl, —NR4R5, aryl, aralkyl, heteroaryl, cycloalkyl, heterocyclyl, —S(O)yR8, —C(O)R8, —C(O)OR8, —C(O)NR4R5, —S(O)2NR4R5, —NR′(C═NR4)NR4R5, —OC(O)NR4R5, —OC(O)OR8, —C(═NR4)NR4R5, —NR4R5, or —NR7C(O)R7
• R8 is hydrogen, C1-C6 alkyl, C1-C6 alkenyl, C1-C6 alkynyl, —NR4R5, aryl, aralkyl, heteroaryl, cycloalkyl, tetrahydrofuranyl, pyranyl, 1,4-dioxanyl, 1,3-dioxanyl, piperidinyl, pyrrolidinyl, morpholinyl, tetrahydrothiopyranyl, tetrahydrothiophenyl, or —S(O)2R9;
• R9 is C1-C6 alkyl or C1-C6 haloalkyl;
• R′ is C1-C3 alkylene;
• and
• R″ is —OR7, —OC(O)NR4R5, —OC(O)OR7, —OC(O)R7.