A compound of general formula in which: R 1 represents a group selected from: wherein * indicates the point of attachment of said group with the rest of the molecule; R 2 represents hydrogen, halogen, -NR 7 R 8, CN, C 1 -C 6 -alkyl, C 1 -C 6 -alkoxy, 3-to 10-membered heterocycloalkoxy, C 2 -C 6 -alkenyl, C 3 -C 6 -cycloalkyl, 3-to 10-membered heterocycloalkyl, 4-to 10-membered heterocycloalkenyl, phenyl, heteroaryl, - OR 7, - NR 7 R 8, -(SO 2)R 9, - R 9, -SR 9, -(SO 2)NR 7 R 8, -NR 7 (SO 2)R 9, -( =NR 11)R 10, -N= R 9 R 10, -SiR 10 R 11 R 12, - (OR 7) 2, - (OR 7)R 10 or - (R 10) 2, wherein each C 1 -C 6 -alkyl, C 1 -C 6 -alkoxy, 3-to 10-membered heterocycloalkoxy, C 2 -C 6 -alkenyl, C 3 -C 6 -cycloalkyl, 3- to 10-membered heterocycloalkyl, phenyl or heteroaryl is optionally substituted, one or more times, independently from each other, with halogen, OH, -NR 7 R 8, C 1 -C 6 -alkyl optionally substituted with hydroxyl or phenyl, C 1 -C 6 -haloalkyl, C 1 -C 6 -alkoxy, C 3 -C 6 -cycloalkyl, 3-to 6-membered heterocycloalkyl, phenyl, - OR 7, - NR 7 R 8, -NR 7 R 10, NR 8 OR 7, -NR 8 NR 7 R 8, -(SO 2)R 9, - R 9, -SR 9,-(SO 2)NR 7 R 8, -NR 7 (SO 2)R 9, -( =NR 11)R 10, -N= R 9 R 10, - (OR 7) 2, - (OR 7)R 10, - (R 10) 2 or with a heteroaryl group which is optionally substituted, one or more times, with C 1 -C 4 -alkyl; wherein each 4-to 10-membered heterocycloalkenyl is optionally substituted, one or more times, indepently from each other, with C 1 -C 4 -alkyl; R 3, R 4 represent, independently from each other, hydrogen or methyl; R 7, R 8 represent, independently from each other, hydrogen, C 1 -C 6 -alkyl, C 3 -C 6 -cycloalkyl or phenyl, which phenyl is optionally substituted, one or more times, with halogen; or R 7 and R 8 together represent a 4-, 5-, 6- or 7-membered cyclic amine group, which is optionally substituted, one or more times, independently from each other, with a substituent selected from C 1 -C 6 -alkyl, C 1 -C 6 -haloalkyl, said 4-, 5-, 6- or 7-membered cyclic amine group optionally containing one further heteroatom selected from the group consisting of O, N and S; R 9 represents C 1 -C 4 -alkyl or phenyl, wherein each C 1 -C 4 -alkyl or phenyl is optionally substituted, one or more times, independently from each other, with R 13; R 10 represents C 1 -C 4 -alkyl; or R 9 and R 10 together, in case of -N= R 9 R 10 group, represent a 5-to 8-membered heterocycloalkyl group; R 11 represents hydrogen, C 1 -C 4 -alkyl, - OR 7, - NR 7 R 8 or CN; R 12 represents hydrogen or C 1 -C 4 -alkyl; R 13 represents halogen, OH, -NR 7 R 8, CN, NO 2, C 1 -C 6 -alkyl, C 1 -C 6 -haloalkyl, C 1 -C 6 -alkoxy, C 1 -C 6 -haloalkoxy, C 2 -C 6 -alkenyl, C 3 -C 6 -cycloalkyl, - OR 7 or - NR 7 R 8; or a stereoisomer, a tautomer, an N-oxide, a hydrate, a solvate, or a salt thereof, or a mixture of same. R 1 represents a group selected from: wherein * indicates the point of attachment of said group with the rest of the molecule; R 2 represents hydrogen, halogen, -NR 7 R 8, CN, C 1 -C 6 -alkyl, C 1 -C 6 -alkoxy, 3-to 10-membered heterocycloalkoxy, C 2 -C 6 -alkenyl, C 3 -C 6 -cycloalkyl, 3-to 10-membered heterocycloalkyl, 4-to 10-membered heterocycloalkenyl, phenyl, heteroaryl, - OR 7, - NR 7 R 8, -(SO 2)R 9, - R 9, -SR 9, -(SO 2)NR 7 R 8, -NR 7 (SO 2)R 9, -( =NR 11)R 10, -N= R 9 R 10, -SiR 10 R 11 R 12, - (OR 7) 2, - (OR 7)R 10 or - (R 10) 2, wherein each C 1 -C 6 -alkyl, C 1 -C 6 -alkoxy, 3-to 10-membered heterocycloalkoxy, C 2 -C 6 -alkenyl, C 3 -C 6 -cycloalkyl, 3- to 10-membered heterocycloalkyl, phenyl or heteroaryl is optionally substituted, one or more times, independently from each other, with halogen, OH, -NR 7 R 8, C 1 -C 6 -alkyl optionally substituted with hydroxyl or phenyl, C 1 -C 6 -haloalkyl, C 1 -C 6 -alkoxy, C 3 -C 6 -cycloalkyl, 3-to 6-membered heterocycloalkyl, phenyl, - OR 7, - NR 7 R 8, -NR 7 R 10, NR 8 OR 7, -NR 8 NR 7 R 8, -(SO 2)R 9, - R 9, -SR 9,-(SO 2)NR 7 R 8, -NR 7 (SO 2)R 9, -( =NR 11)R 10, -N= R 9 R 10, - (OR 7) 2, - (OR 7)R 10, - (R 10) 2 or with a heteroaryl group which is optionally substituted, one or more times, with C 1 -C 4 -alkyl; wherein each 4-to 10-membered heterocycloalkenyl is optionally substituted, one or more times, indepently from each other, with C 1 -C 4 -alkyl; R 3, R 4 represent, independently from each other, hydrogen or methyl; R 7, R 8 represent, independently from each other, hydrogen, C 1 -C 6 -alkyl, C 3 -C 6 -cycloalkyl or phenyl, which phenyl is optionally substituted, one or more times, with halogen; or R 7 and R 8 together represent a 4-, 5-, 6- or 7-membered cyclic amine group, which is optionally substituted, one or more times, independently from each other, with a substituent selected from C 1 -C 6 -alkyl, C 1 -C 6 -haloalkyl, said 4-, 5-, 6- or 7-membered cyclic amine group optionally containing one further heteroatom selected from the group consisting of O, N and S; R 9 represents C 1 -C 4 -alkyl or phenyl, wherein each C 1 -C 4 -alkyl or phenyl is optionally substituted, one or more times, independently from each other, with R 13; R 10 represents C 1 -C 4 -alkyl; or R 9 and R 10 together, in case of -N= R 9 R 10 group, represent a 5-to 8-membered heterocycloalkyl group; R 11 represents hydrogen, C 1 -C 4 -alkyl, - OR 7, - NR 7 R 8 or CN; R 12 represents hydrogen or C 1 -C 4 -alkyl; R 13 represents halogen, OH, -NR 7 R 8, CN, NO 2, C 1 -C 6 -alkyl, C 1 -C 6 -haloalkyl, C 1 -C 6 -alkoxy, C 1 -C 6 -haloalkoxy, C 2 -C 6 -alkenyl, C 3 -C 6 -cycloalkyl, - OR 7 or - NR 7 R 8;