Compositions and methods for modulating c-kit and PDGFR receptors

A compound of Formula (1):

• or a pharmaceutically acceptable salt thereof, wherein:
• Y is CR and Z is N;
• L is NR—C(O), C(O)NR, C(O)NRC(O)NR, NRC(O)NRC(O), NRC(S)NRCO, NRS(O)0-2 or NRCONRS(O)0-2;
• R1 is halo, (CR2)kNR7R8, (CR2)kOR9, (CR2)kSR9, aryl or heteroaryl;
• or R1 is C1-6 alkyl, C2-6 alkenyl or C2-6 alkynyl, wherein each of said C1-6 alkyl and C2-6 alkenyl is optionally substituted with ureayl, guanidyl, O(C1-6 alkyl), or optionally substituted with C3-7 cycloalkyl, phenyl, or heteroaryl, said phenyl is further optionally substituted with halo or an optionally halogenated C1-6 alkyl;
• R2 is (CR2)1-4OR9, (CR2)1-4NR7R8 or aryl;
• or R2 is C1-6 alkyl, C2-6 alkenyl or C2-6 alkynyl, wherein said C1-6 alkyl is optionally substituted with phenyl, or heteroaryl;
• R3 is halo or C1-6 alkyl;
• R4 is (CR2)kR6, dihydroindenyl, C1-6 alkyl or (CR2)kOR9;
• R5 is H, halo or C1-6 alkyl;
• R6 is C3-7 cycloalkyl, aryl, heterocyclic ring or heteroaryl, each of which is optionally substituted with halo, cyano, nitro, NR7R8, NRCOR7, (CR2)pOR9′, (CR2)pR10, or a C1-6 alkyl optionally substituted with halo, hydroxyl, C1-6 alkoxy or cyano;
• R9′ is H, an optionally halogenated C1-6 alkyl or (CR2)pR10;
• R10 is C3-7 cycloalkyl, aryl, 5-7 membered heterocyclic ring, or heteroaryl, each of which is optionally substituted with halo, cyano, nitro, NR7R8, NRCOR7, NRC(O)(CR2)pNR7R8(7), NRCONR(CR2)pNR7R8, OR9, or C1-6 alkyl optionally substituted with hydroxyl;
• R7, R8 and R9 are independently H or C1-6 alkyl;
• or R7 and R8 together with N in each NR7R8 may form a 5-7 membered heterocyclic ring;
• each R is H or C1-6 alkyl;
• k is 0-6;
• and
• n is 0-2;
• provided L is C(O)NRC(O)NR, NRC(O)NRC(O), NRC(S)NRCO or NRCONRS(O)0-2 when R1 is halo or (CR2)kNR7R8 and R2 is C1-6 alkyl.