MST1 kinase inhibitor and use thereof

A kinase inhibitor compound of Formula (I) or a pharmaceutically acceptable salt, solvate, ester, acid, or prodrug thereof,

• wherein,
• R1 is selected from
• and C3-C6 heterocycloalkyl;
• R2 and R3 are each independently selected from C1-C6 alkyl;
• R4 is selected from C3-C6 cycloalkyl, C4-C8 cycloalkylalkyl, C2-C6 spirocycloalkyl, aryl optionally substituted with 1-3 R9, aryl-C1-C6 alkyl optionally substituted with 1-3 R9 and heteroaryl optionally substituted with 1-3 R9;
• R5 and R6 are each independently selected from hydrogen, C1-C6 alkyl, C3-C6 cycloalkyl, C4-C8 cycloalkylalkyl, C3-C6 heterocycloalkyl, hydroxyl C1-C6 alkyl, C1-C6 alkylamino, C1-C6 haloalkyl, C1-C6 alkylamino C1-C6 alkyl, C1-C6 alkoxy C1-C6 alkyl, and C3-C6 heterocyclyl C1-C6 alkyl;
• R7 and R8 are each independently selected from C1-C6 alkyl, or R7 and R8, together with the carbon atom attached thereto, form C3-C6 cycloalkyl or C3-C6 heterocyclyl;
• and
• R9 is selected from halogen, C1-C6 alkyl, C1-C6 alkoxy, and C1-C6 haloalkyl.