A compound of formula (A): where: Ar is independently selected from C6-C10 aryl and a 5-10 membered heteroaryl where: C6-C10 aryl and heteroaryl are optionally substituted with one to three groups selected from F, Cl, Br , I, OR22, OR25, NR23R24, NHOH, NO2, CN, CF3, C1-C6 alkyl, C2-C6 alkenyl, C2-C6 alkynyl, C3-C7 cycloalkyl, 3-7 membered heterocycloalkyl, phenyl, 5 or heteroaryl 6 members, arylalkyl, C (= O) R22, CO2R22, OC (= O) R22, C (= O) NR23R24, NR21C (= O) R22, NR21CO2R22, OC (= O) NR23R24, NR21C (= S) R22 and S (O) and R22； X is O, S (O) and, N (R10), OC (R22) 2, (R22) 2CO, C (R22) 2NR21, NR21C (R22) 2, C (= O) N (R21), NR21C ( = O), S (O) 2NR22, NR22S (O) 2, C (R22) 2C (R22) 2, CR21 = CR21 or C≡C； Y is C1-C6 alkylene； or (C1-C4 alkylene) m-Z- (C1-C4 alkylene) n； wherein said alkylene groups are optionally substituted with one to three R20 groups； Z is O, NR10A, S (O) and, CR21 = CR21, C≡C, C6-C10 arylene, 5-10 membered heteroarylene, C3-C6 cycloalkylene, or 3-6 membered heterocycloalkylene； wherein said arylene, heteroarylene, cycloalkylene and heterocycloalkylene groups are optionally substituted with one to three R20 groups； R1 is selected from NR12R13, NR21C (= O) R14, C (= O) R14, CO2R11, OC (= O) R11, C (= O) NR12R13, C (= NR11) NR12R13, OC (= O) NR12R13, NR21S (O) 2R11, NR21C (= O) NR12R13 and NR21S (= O) 2NR12R13； R2 and R3 are each independently selected from H, F, Cl, Br, I, OR22, OR25, NR23R24, NHOH, NO2, CN, CF3, C1-C6 alkyl, C2-C6 alkenyl, C2-C6 alkynyl, C3- C7 cycloalkyl, 3-7 membered heterocycloalkyl, phenyl, 5- or 6 membered heteroaryl, arylalkyl, C (= O) R22, CO2R22, OC (= O) R22, C (= O) NR23R24, NR21C (= O) R22 , NR21CO2R22, OC (= O) NR23R24, NR21C (= S) R22 and S (O) and R22； R10 and R10A are each independently selected from H, C1-C6 alkyl, C6-C10 aryl, C (= O) R14 and S (O) and R14； wherein said alkyl and aryl groups are optionally substituted with one to three R20 groups； R11 each time it appears is independently selected from H, C3-C7
