A compound of the formula (I), or a salt thereof: wherein: X is N or CH； Z1 is N or CR1c； Z2 is N or CR1d, where at least one of Z1 and Z2 is not N； R1a is selected from the group consisting of hydrogen, alkyl of 1 to 6 carbon atoms, alkoxy of 1 to 6 carbon atoms, halo-alkyl of 1 to 6 carbon atoms, halo-alkoxy of 1 to 6 atoms of carbon, cyano or halogen； R1b is selected from the group consisting of hydrogen, amino, hydroxyl, alkyl of 1 to 6 carbon atoms, alkoxy of 1 to 6 carbon atoms, and mono- and di-alkyl of 1 to 4 carbon-amino atoms ； R1c is hydrogen, halogen, or alkyl of 1 to 6 carbon atoms； R1d is selected from the group consisting of hydrogen, halogen, alkyl of 1 to 6 carbon atoms, and alkoxy of 1 to 6 carbon atoms； R1e is selected from hydrogen, halogen, cyano, alkyl of 1 to 6 carbon atoms, halo-alkyl of 1 to 6 carbon atoms, alkoxy of 1 to 6 carbon atoms and halo-alkoxy of 1 to 6 atoms of carbon, sulfone, cycloalkyl of 3 to 7 carbon atoms； or R1a and R1b taken in combination, form a saturated or unsaturated 5-membered heterocyclic ring having one or two ring heteroatoms selected from N, O or S, whose heterocyclic ring is substituted with 0, 1 or 2 alkyl substituents from 1 to 6 independently selected carbon or halogen atoms； wherein at least one of R1a and R1e is not hydrogen； R2 is selected from the group consisting of hydrogen, alkyl of 1 to 6 carbon atoms, alkoxy of 1 to 6 carbon atoms, thioalkyl of 1 to 6 carbon atoms, cycloalkyl of 3 to 7 carbon atoms, cycloalkyl of 3 to 7 carbon-alkyl atoms of 1 to 4 carbon atoms and (CH2) pNR2aR2b, wherein each alkyl and alkoxy group is substituted with 0 or 2 substituents selected from the group consisting of hydroxyl, halogen, and alkoxy of 1 to 4 carbon atoms, amino, mono- and di-alkyl of 1 to 4 carbon-amino atoms； p is 0 or 1； R2a is hydrogen, alkyl of 1 to 6 carbon atoms, or hydroxy-alkyl of 1 to 6 carbon atoms； R2b is hydrogen, alkyl of 1 to 6 carbon atoms, cycloalkyl of 3 to 7 carbon atoms, or cycloalkyl of 3 to
