Compounds of formula wherein R a is hydrogen or C 1-7 -alkyl; R 1 is or may be selected from the group consisting of R 8 is hydrogen, halogen or aryl optionally substituted by halogen; X is a bond, -(CH 2) n -, -CHRCH 2, -CHR(CH 2) 2 -, -O-CHRCH 2 - or and R is C 1-7 -alkyl or C 1-7 -alkyl substituted by halogen; R 2 is a) C 1-7 -alkyl; b) hydrogen; c) NH-aryl, optionally substituted by one or more substituents selected from halogen or C 1-7 -alkyl substituted by halogen; d) NH-heteroaryl, optionally substituted by one or more substituents selected from halogen or C 1-7 -alkyl substituted by halogen; e) (CR'R") m -cycloalkyl, optionally substituted by halogen, C 1-7 -alkyl, C 1-7 -alkyl substituted by halogen, halogen-substituted phenyl or by heteroaryl; f) heterocycloalkyl, optionally substituted by halogen or C 1-7 -alkyl substituted by halogen; g) (CR'R") m -heteroaryl, optionally substituted by halogen, C 1-7 -alkoxy, C 1-7 -alkyl substituted by halogen, C 1-7 -alkoxy substituted by halogen, C 1-7 -alkyl, cycloalkyl, NHC - C 1-7 -alkyl, cyano, S 2 - C 1-7 -alkyl, NR 6 R 7, or by heteroaryl or by heterocyclyl which is optionally substituted by halogen; h) (CR'R") m -aryl, optionally substituted by halogen, C 1-7 -alkyl substituted by halogen, C 1-7 -alkoxy substituted by halogen, C 1-7 -alkyl, alkynyl, C 1-7 -alkoxy, CH 2 - C 1-7 -alkoxy or cyano; i) -O(CH 2) o -aryl, optionally substituted by halogen, C 1-7 -alkoxy or C 1-7 -alkyl substituted by halogen; R' and R" are independently from each other hydrogen, C 1-7 -alkoxy or C 1-7 -alkyl; or may form together with the C-atom a cycloalkyl group; R 3 is aryl or heteroaryl, wherein the aromatic rings are optionally substituted by one or more substituents selected from halogen or C 1-7 -alkoxy; R 4 is C 1-7 -alkyl, aryl or heteroaryl, wherein the aromatic rings are optionally substituted by one or more substituents selected from halogen, cyano or C 1-7 -alkoxy; R 5 is hydrogen, C 1-7 -alkyl or aryl substituted by halogen: or R 4 and R 5 may form together with the N-atom to which they are attached a heterocyclic ring; R 6 /R 7 are independently from each other hydrogen, lower alkyl or (CH 2) 2 -O-lower alkyl; m is 0, 1 or 2; n is 1, 2 or 3; o is 0 or 1; p is 0, 1 or 2; or a pharmaceutically suitable acid addition salt thereof. R a is hydrogen or C 1-7 -alkyl; R 1 is or may be selected from the group consisting of R 8 is hydrogen, halogen or aryl optionally substituted by halogen; X is a bond, -(CH 2) n -, -CHRCH 2, -CHR(CH 2) 2 -, -O-CHRCH 2 - or and R is C 1-7 -alkyl or C 1-7 -alkyl substituted by halogen; R 2 is a) C 1-7 -alkyl; b) hydrogen; c) NH-aryl, optionally substituted by one or more substituents selected from halogen or C 1-7 -alkyl substituted by halogen; d) NH-heteroaryl, optionally substituted by one or more substituents selected from halogen or C 1-7 -alkyl substituted by halogen; e) (CR'R") m -cycloalkyl, optionally substituted by halogen, C 1-7 -alkyl, C 1-7 -alkyl substituted by halogen, halogen-substituted phenyl or by heteroaryl; f) heterocycloalkyl, optionally substituted by halogen or C 1-7 -alkyl substituted by halogen; g) (CR'R") m -heteroaryl, optionally substituted by halogen, C 1-7 -alkoxy, C 1-7 -alkyl substituted by halogen, C 1-7 -alkoxy substituted by halogen, C 1-7 -alkyl, cycloalkyl, NHC - C 1-7 -alkyl, cyano, S 2 - C 1-7 -alkyl, NR 6 R 7, or by heteroaryl or by heterocyclyl which is optionally substituted by halogen; h) (CR'R") m -aryl, optionally substituted by halogen, C 1-7 -alkyl substituted by halogen, C 1-7 -alkoxy substituted by halogen, C 1-7 -alkyl, alkynyl, C 1-7 -alkoxy, CH 2 - C 1-7 -alkoxy or cyano; i) -O(CH 2) o -aryl, optionally substituted by halogen, C 1-7 -alkoxy or C 1-7 -alkyl substituted by halogen; a) C 1-7 -alkyl; b) hydrogen; c) NH-aryl, optionally substituted by one or more substituents selected from halogen or C 1-7 -alkyl substituted by halogen; d) NH-heteroaryl, optionally substituted by one or more substituents selected from halogen or C 1-7 -alkyl substituted by halogen; e) (CR'R") m -cycloalkyl, optionally substituted by halogen, C 1-7 -alkyl, C 1-7 -alkyl substituted by halogen, halogen-substituted phenyl or by heteroaryl; f) heterocycloalkyl, optionally substituted by halogen or C 1-7 -alkyl substituted by halogen; g) (CR'R") m -heteroaryl, optionally substituted by halogen, C 1-7 -alkoxy, C 1-7 -alkyl substituted by halogen, C 1-7 -alkoxy substituted by halogen, C 1-7 -alkyl, cycloalkyl, NHC - C 1-7 -alkyl, cyano, S 2 - C 1-7 -alkyl, NR 6 R 7, or by heteroaryl or by heterocyclyl which is optionally substituted by halogen; h) (CR'R") m -aryl, optionally substituted by halogen, C 1-7 -alkyl substituted by halogen, C 1-7 -alkoxy substituted by halogen, C 1-7 -alkyl, alkynyl, C 1-7 -alkoxy, CH 2 - C 1-7 -alkoxy or cyano; i) -O(CH 2) o -aryl, optionally substituted by halogen, C 1-7 -alkoxy or C 1-7 -alkyl substituted by halogen; R' and R" are independently from each other hydrogen, C 1-7 -alkoxy or C 1-7 -alkyl; or may form together with the C-atom a cycloalkyl group; R 3 is aryl or heteroaryl, wherein the aromatic rings are optionally substituted by one or more substituents selected from halogen or C 1-7 -alkoxy; R 4 is C 1-7 -alkyl, aryl or heteroaryl, wherein the aromatic rings are optionally substituted by one or more substituents selected from halogen, cyano or C 1-7 -alkoxy; R 5 is hydrogen, C 1-7 -alkyl or aryl substituted by halogen: or R 4 and R 5 may form together with the N-atom to which they are attached a heterocyclic ring; R 6 /R 7 are independently from each other hydrogen, lower alkyl or (CH 2) 2 -O-lower alkyl; m is 0, 1 or 2; n is 1, 2 or 3; o is 0 or 1; p is 0, 1 or 2;