A compound of Formula I or a salt thereof, wherein: the compound of Formula I corresponds to: R 1 is selected from the group consisting of cyano, halogen, methyl, and ethyl; R 2 is selected from the group consisting of hydrogen, halogen, methyl, and ethyl; R 3 is selected from the group consisting of halogen, methyl, and ethyl; R 4 is selected from the group consisting of hydrogen, halogen, methyl, ethyl, and methoxy; as to R 5 and R 6: R 5 and R 6 are independently selected from the group consisting of hydrogen, C 1 -C 6 -alkyl, and hydroxy-C 1 -C 6 -alkyl; or R 5 and R 6, together with the nitrogen to which they are both attached, form a 5- or 6-member heterocycloalkyl, wherein: the heterocycloalkyl is optionally substituted with one or more substituents independently selected from the group consisting of halogen, hydro xyl, and C 1 -C 4 -alkyl; R 7 and R 8 are independently selected from the group consisting of hydrogen and C 1 -C 4 -alkyl; R 9 is selected from the group consisting of C 1 -C 6 -alkyl, C 3 -C 6 -cycloalkyl, C 1 -C 6 -alkyl-C 3 -C 6 -cycloalkyl, halo-C 1 -C 6 -alkyl, C 1 -C 6 -alkoxy, halo-C 1 -C 6 -alkoxy, and C 1 -C 6 -alkoxy-C 1 -C 6 -alkyl; and X is selected from a bond, CH 2, and O. the compound of Formula I corresponds to: R 1 is selected from the group consisting of cyano, halogen, methyl, and ethyl; R 2 is selected from the group consisting of hydrogen, halogen, methyl, and ethyl; R 3 is selected from the group consisting of halogen, methyl, and ethyl; R 4 is selected from the group consisting of hydrogen, halogen, methyl, ethyl, and methoxy; as to R 5 and R 6: R 5 and R 6 are independently selected from the group consisting of hydrogen, C 1 -C 6 -alkyl, and hydroxy-C 1 -C 6 -alkyl; or R 5 and R 6, together with the nitrogen to which they are both attached, form a 5- or 6-member heterocycloalkyl, wherein: the heterocycloalkyl is optionally substituted with one or more substituents independently selected from the group consisting of halogen, hydro xyl, and C 1 -C 4 -alkyl; R 7 and R 8 are independently selected from the group consisting of hydrogen and C 1 -C 4 -alkyl; R 9 is selected from the group consisting of C 1 -C 6 -alkyl, C 3 -C 6 -cycloalkyl, C 1 -C 6 -alkyl-C 3 -C 6 -cycloalkyl, halo-C 1 -C 6 -alkyl, C 1 -C 6 -alkoxy, halo-C 1 -C 6 -alkoxy, and C 1 -C 6 -alkoxy-C 1 -C 6 -alkyl; and X is selected from a bond, CH 2, and O. R 1 is selected from the group consisting of cyano, halogen, methyl, and ethyl; R 2 is selected from the group consisting of hydrogen, halogen, methyl, and ethyl; R 3 is selected from the group consisting of halogen, methyl, and ethyl; R 4 is selected from the group consisting of hydrogen, halogen, methyl, ethyl, and methoxy; as to R 5 and R 6: R 5 and R 6 are independently selected from the group consisting of hydrogen, C 1 -C 6 -alkyl, and hydroxy-C 1 -C 6 -alkyl; or R 5 and R 6, together with the nitrogen to which they are both attached, form a 5- or 6-member heterocycloalkyl, wherein: the heterocycloalkyl is optionally substituted with one or more substituents independently selected from the group consisting of halogen, hydro xyl, and C 1 -C 4 -alkyl; R 5 and R 6 are independently selected from the group consisting of hydrogen, C 1 -C 6 -alkyl, and hydroxy-C 1 -C 6 -alkyl; or R 5 and R 6, together with the nitrogen to which they are both attached, form a 5- or 6-member heterocycloalkyl, wherein: the heterocycloalkyl is optionally substituted with one or more substituents independently selected from the group consisting of halogen, hydro xyl, and C 1 -C 4 -alkyl; the heterocycloalkyl is optionally substituted with one or more substituents independently selected from the group consisting of halogen, hydro xyl, and C 1 -C 4 -alkyl; R 7 and R 8 are independently selected from the group consisting of hydrogen and C 1 -C 4 -alkyl; R 9 is selected from the group consisting of C 1 -C 6 -alkyl, C 3 -C 6 -cycloalkyl, C 1 -C 6 -alkyl-C 3 -C 6 -cycloalkyl, halo-C 1 -C 6 -alkyl, C 1 -C 6 -alkoxy, halo-C 1 -C 6 -alkoxy, and C 1 -C 6 -alkoxy-C 1 -C 6 -alkyl; and X is selected from a bond, CH 2, and O.