Compounds of the formula ** Formula ** in which B1 is CR7 or N； B2 is CR8 or N； R1 is selected from the group consisting of phenyl, said phenyl being unsubstituted or substituted with one, two or three groups selected from the group consisting of C1-7 alkyl, C1-7 cycloalkyl, halogen, hydroxy, C1-7 alkoxy , halogen-C1-7 alkyl, halogen-C1-7 alkoxy, cycloalkyloxy, cycloalkyl-C1-7 alkoxy, cyano, cyano-C1-7 alkoxy, carboxyl, carboxy-C1-7 alkyl, C1-7 alkoxycarbonyl, hydroxy-alkyl C1-7, hydroxy-C1-7 alkoxy, C1-7 alkoxy-C1-7 alkyl, carboxy-C1-7 alkoxy, C1-7 alkoxycarbonyl-C1-7 alkoxy, amino, C1-7 alkylamino, di-C1- alkylamino 7, phenyl-C 1-7 alkoxy, heterocyclyloxy and heterocyclyl-C 1-7 alkoxy, wherein the heterocyclyl is unsubstituted or substituted with C 1-7 alkoxycarbonyl, heteroaryl, said heteroaryl being unsubstituted or substituted with one, two or three groups selected from the group consisting of C1-7 alkyl, C1-7 cycloalkyl, halogen, hydroxy, C1-7 alkoxy, halogen-C1-7 alkyl, halogen-C1-7 alkoxy, cycloalkyloxy, ci chloalkyl-C1-7 alkoxy, heterocyclyloxy and heterocyclyl-C1-7 alkoxy, wherein the heterocyclyl is unsubstituted or substituted with C1-7 alkoxycarbonyl, 3,6-dihydro-2H-pyran-4-yl, and piperidinyl, being said piperidinyl substituted with one to four C1-7 alkyl groups； R2 is selected from the group consisting of hydrogen, C1-7 alkyl, halogen, halogen-C1-7 alkyl, halogen-C1-7 alkoxy, cyano, C1-7 alkoxy, amino, C1-7 alkylamino, C1-alkylamino -7, aminocarbonyl, C 1-7 alkylaminocarbonyl, di- C 1-7 alkylaminocarbonyl, hydroxyC 1-7 alkyl- (C 1-7 alkyl) amino, C 1-7 alkoxy-C 1-7 alkyl- (C 1-7 alkyl) amino, and heteroaryl； R2a is selected from the group consisting of hydrogen, methyl and halogen； R3 is selected from the group consisting of C1-7 alkyl, halogen-C1-7 alkyl, hydroxy-C1-7 alkyl, C1-7 alkoxy-C1-7 alkyl, C1-7 alkylcarbonyl-C1-7 alkyl, carboxy- C1-7 alkyl, C1-7 alkoxycarbonyl-C1-7 alkyl, cyano-C1-7 alkyl, aminocarbonyl-C1-7 alkyl, alkylaminocarbonyl C1-7-C1
