A compound of formula I wherein Ar 1 denotes a phenyl ring or a 5- or 6-membered monocyclic heteroaryl-group which has 1 to 4 heteroatoms independently selected from the group consisting of N, O and S; and wherein said phenyl ring or said 5- or 6-membered monocyclic heteroaryl-group may be linked to a group Ar 2 via a single bond or may be condensed to a group Ar 2, wherein one or more C-atoms may be substituted independently of one another with a substituent L1; and wherein one or more imino-groups may be substituted independently of one another with a substituent R N0; and Ar 2 denotes a 5- or 6-membered saturated or unsaturated carbocyclic ring which may have 1 or 2 heteroatoms independently selected from the group consisting of N, O and S, or may have 3 or 4 N-atoms; and W denotes a single bond, -C≡C-, -CH=CH-, -CH 2 -CH 2 - or -CH 2 -O-; R 1 denotes C 1-4 -alkyl; R 2 denotes H or C 1-4 -alkyl; R 3 denotes C 3-6 -alkenyl, C 3-6 -alkynyl, C 3-6 -cycloalkyl or R N1 R N2 N-, wherein each of said alkyl, alkenyl, alkynyl and cycloalkyl groups may be substituted with one or more substituents selected from the group consisting of R N1 R N2 N-, C 1 - 4 -alkyl-O-C(=O)-R N0 N-, HO-, C 1-4 -alkyloxy, C 3-7 -cycloalkyl, phenyl and pyridinyl, wherein said cycloalkyl, phenyl and pyridinyl may be substituted with one or more substituents L2; or denotes C 1-6 -alkyl, wherein the alkyl group may be mono- or polyfluorinated; R N0 denotes H or C 1-4 -alkyl; R N1, R N2 independently of each other selected from H, C 1-4 -alkyl, phenyl, pyridinyl, phenyl-C 1-3 -alkyl, pyridinyl-C 1-3 -alkyl or R N1, R N2 are linked to each other to form with the N-atom of the R N1 R N2 N- group a heterocyclic ring selected from the group consisting of pyrrolidinyl, piperidinyl, morpholinyl, thiomorpholinyl, piperazinyl or 4-(C 1-4 -alkyl)-piperazinyl; L0, L1 independently of each other selected from the group consisting of F, Cl, Br, cyano, OH, C 1-4 -alkyl, C 2-4 -alkenyl, C 1-4 -alkyloxy, C 1-4 -alkylcarbonyl, R N1 R N2 N-, R N1 R N2 N-C 1-3 -alkyl-, R N1 R N2 N-CO-, C 1-4 -alkyl-CO-NR N0 - and C 1-4 -alkyl-SO 2 -NR N0 -, wherein alkyl-groups may be mono- or polyfluorinated; L2 independently of each other selected from the group consisting of F, Cl, Br, cyano, OH, C 1-4 - alkyl, C 1-4 -alkyloxy, R N1 R N2 N-, R N1 R N2 N-C 1-3 -alkyl-, wherein alkyl-groups may be mono- or polyfluorinated; n denotes an integer from 0 to 4; or a salt thereof. Ar 1 denotes a phenyl ring or a 5- or 6-membered monocyclic heteroaryl-group which has 1 to 4 heteroatoms independently selected from the group consisting of N, O and S; and wherein said phenyl ring or said 5- or 6-membered monocyclic heteroaryl-group may be linked to a group Ar 2 via a single bond or may be condensed to a group Ar 2, wherein one or more C-atoms may be substituted independently of one another with a substituent L1; and wherein one or more imino-groups may be substituted independently of one another with a substituent R N0; and Ar 2 denotes a 5- or 6-membered saturated or unsaturated carbocyclic ring which may have 1 or 2 heteroatoms independently selected from the group consisting of N, O and S, or may have 3 or 4 N-atoms; and W denotes a single bond, -C≡C-, -CH=CH-, -CH 2 -CH 2 - or -CH 2 -O-; R 1 denotes C 1-4 -alkyl; R 2 denotes H or C 1-4 -alkyl; R 3 denotes C 3-6 -alkenyl, C 3-6 -alkynyl, C 3-6 -cycloalkyl or R N1 R N2 N-, wherein each of said alkyl, alkenyl, alkynyl and cycloalkyl groups may be substituted with one or more substituents selected from the group consisting of R N1 R N2 N-, C 1 - 4 -alkyl-O-C(=O)-R N0 N-, HO-, C 1-4 -alkyloxy, C 3-7 -cycloalkyl, phenyl and pyridinyl, wherein said cycloalkyl, phenyl and pyridinyl may be substituted with one or more substituents L2; or denotes C 1-6 -alkyl, wherein the alkyl group may be mono- or polyfluorinated; R N0 denotes H or C 1-4 -alkyl; R N1, R N2 independently of each other selected from H, C 1-4 -alkyl, phenyl, pyridinyl, phenyl-C 1-3 -alkyl, pyridinyl-C 1-3 -alkyl or R N1, R N2 are linked to each other to form with the N-atom of the R N1 R N2 N- group a heterocyclic ring selected from the group consisting of pyrrolidinyl, piperidinyl, morpholinyl, thiomorpholinyl, piperazinyl or 4-(C 1-4 -alkyl)-piperazinyl; L0, L1 independently of each other selected from the group consisting of F, Cl, Br, cyano, OH, C 1-4 -alkyl, C 2-4 -alkenyl, C 1-4 -alkyloxy, C 1-4 -alkylcarbonyl, R N1 R N2 N-, R N1 R N2 N-C 1-3 -alkyl-, R N1 R N2 N-CO-, C 1-4 -alkyl-CO-NR N0 - and C 1-4 -alkyl-SO 2 -NR N0 -, wherein alkyl-groups may be mono- or polyfluorinated; L2 independently of each other selected from the group consisting of F, Cl, Br, cyano, OH, C 1-4 - alkyl, C 1-4 -alkyloxy, R N1 R N2 N-, R N1 R N2 N-C 1-3 -alkyl-, wherein alkyl-groups may be mono- or polyfluorinated; n denotes an integer from 0 to 4;