Novel oxazole derivatives that inhibit syk

A compound of formula (I):

• or a pharmaceutically acceptable salt thereof, wherein:
• R1, R2, R3, and R4 are each independently selected from the group consisting of:
• hydrogen,
• cyano,
• haloalkyl,
• halogen,
• alkyl group optionally substituted with a group selected from the group consisting of an heterocycle and —NRR′,
• alkoxy group optionally substituted with a group selected from the group consisting of an heterocycle and —NRR′,
• water-solubilising group,
• heterocycle,
• —CO—NRR′,
• —SO2—NRR′,
• —NRR′,
• —NR—CO—R′, and
• —NR—SO2R′ group;
• wherein R and R′ are each independently selected from the group consisting of hydrogen and alkyl group;
• R5 is an alkyl group optionally substituted with a group selected from the group consisting of heterocycle, hydroxyl, cyano, amino, and alkoxy;
• R6 is selected from the group consisting of hydrogen, alkyl group, and cycloalkyl group;
• W is selected from the group consisting of aryl and heteroaryl groups, the aryl or heteroaryl groups being optionally substituted by one or more substituents selected from the group consisting of:
• cyano,
• haloalkyl,
• halogen,
• an alkyl group optionally substituted with an heterocycle,
• a cycloalkyl group,
• an alkoxy group optionally substituted with an heterocycle,
• an aryl group,
• a heteroaryl group,
• a heterocycloalkyl group optionally substituted with an alkyl group,
• a water-solubilising group,
• —CO—NRR′,
• —SO2—NRR′,
• —NRR′,
• —NR—CO—R′, and
• —NR—SO2R′ group;
• wherein R and R′ are each independently selected from the group consisting of hydrogen and alkyl group,
• wherein the water-solubilising group is selected from the group consisting of:
• N—(CH2)zR″,
• N—(CH2)z—C(O)R″,
• N—(CH2)z—C(O)OR″,
• N—(CH2)z—S(O)2R″,
• N—(CH2)z—S(O)2OR″,
• N—(CH2)z—C(O)NR″R′″,
• and the following structures (a)-(k):
• wherein:
• L is selected from the group consisting of CH and N;
• M is selected from the group consisting of —CH(R″)—, —CH2—, —O—, —S—, —NH—, —N(—(CH2)z—R″)—, —N(—(CH2)z—C(O)R″)—, —N(—(CH2)z—C(O)OR″)—, —N(—(CH2)z—S(O)2R″)—, —N(—(CH2)z—S(O)2OR″)— and
• —N(—(CH2)z—C(O)NR″R′″)—,
• with the proviso that L and M are not both simultaneously CH and CH2, respectively;
• z is an integer ranging from 0 to 6;
• R″ and R′″ are each independently selected from the group consisting of:
• hydrogen;
• a C1-C10 alkyl group which is optionally substituted with one or more heteroatoms selected from the group consisting of F, Cl, Br, I, O, and N;
• a C1-C10 alkoxy group;
• an unsubstituted aryl;
• and an unsubstituted heteroaryl.