Pyridopyrimidone derivatives, preparation thereof, therapeutic use thereof

A compound corresponding to the formula (I):

• in which:
• R1 is selected from the group consisting of:
• H, (C1-C6)alkyl, (C2-C6)alkenyl, (C2-C6)alkynyl, (C3-C7)cycloalkyl and (C3-C7)cycloalkyl (C1-C6)alkyl;
• R2 and R3 are independently selected from the group consisting of:
• H, halogen, (C1-C4)alkyl, trifluoromethyl and (C1-C4)alkoxy;
• Ar1 represents a radical chosen from:
• R5 is selected from the group consisting of:
• H, cyano, hydroxy(C1-C4)alkyl, (C1-C6)alkoxy(C1-C4)alkyl, —(CH2)nNR6R7, —(CH2)mCO2R6, —(CH2)mCONHNR6R7, —(CH2)mCONR6R7, —(CH2)mCONR7OR8, —(CH2)nNR6COR7 and —(CH2)nNR6COOR7;
• R4 is selected from the group consisting of:
• H, (C1-C4)alkyl and R5;
• when Ar1 takes the value a), then R4 and R5 are not two hydrogen atoms;
• R6 and R7 are independently selected from the group consisting of:
• H, (C1-C4)alkyl, (C3-C7)cycloalkyl and (C3-C7)cycloalkyl(C1-C4)alkyl;
• R7 can also represent a tert-butoxycarbonyl or benzyloxycarbonyl group;
• or R6 and R7, together with the nitrogen atom to which they are bonded, constitute an azetidinyl, pyrrolidinyl, piperidinyl, piperazinyl or morpholinyl radical;
• R8 is selected from the group consisting of:
• H and (C1-C4)alkyl;
• X is O or S;
• X1 and X2 are independently selected from the group consisting of:
• H and —(C1-C6)alkyl-N((C1-C6)alkyl)2;
• when one of X1 and X2 is other than H, then X3 is selected from the group consisting of:
• hydroxyl and (C1-C6)alkoxy;
• when X1 and X2 are H, then X3 is selected from the group consisting of:
• —(CH2)n—CH(NHR9)-CO—R10, —O—(CH2)n—CH(NHR9)-CO—R10 and —NHSO2—(C1-C6)alkyl;
• R9 is selected from the group consisting of:
• H, t-butyloxycarbonyl, benzyloxycarbonyl and (C1-C6)alkyl;
• R10 is selected from the group consisting of:
• hydroxyl, (C1-C6)alkoxy and —NR11R12;
• R11 and R12 are independently selected from the group consisting of:
• H and (C1-C6)alkyl;
• or R11 and R12, together with the nitrogen atom to which they are bonded, constitute an azetidinyl, pyrrolidinyl, piperidinyl, piperazinyl or morpholinyl radical;
• m represents 0, 1, 2 or 3;
• n represents 1, 2 or 3;
• or a pharmaceutically acceptable salt, hydrate or solvate thereof.