A compound of formula in which: R 1 represents a halogen atom or a group selected from: C 1 -C 6 -alkyl, C 3 -C 6 -cycloalkyl, C 1 -C 6 -alkoxy, C 3 -C 6 -cycloalkyloxy, C 1 -C 6 -haloalkyl, C 1 -C 6 -haloalkoxy, cyano, (C 1 -C 6 -alkyl)-S-, (C 1 -C 6 -alkyl)-S(=O)-, (C 1 -C 6 -alkyl)-S(=O) 2 -, (C 1 -C 6 -haloalkyl)-S-, (C 1 -C 6 -haloalkyl)-S(=O)-, (C 1 -C 6 -haloalkyl)-S(=O) 2 -, -C(=O)OR 9, -C(=O)N(R 10)R 11 and -N(R 10)R 11; R 2 represents a hydrogen atom; R 3 represents a hydrogen atom; R 4 represents a hydrogen atom or a halogen atom; R 5 represents a group selected from: -C(=O)OR 9, R 9 OC(=O)-(C 1 -C 6 -alkyl)-, R 9 OC(=O)-(C 2 -C 6 -alkenyl)-, R 9 OC(=O)-(C 1 -C 6 -alkoxy)-, -C(=O)N(R 10)R 11, R 10 (R 11)NC(=OHC 1 -C 6 -alkyl)-, R 10 (R 11)NC(=O)-(C 2 -C 6 -alkenyl)- and R 10 (R 11)NC(=O)-(C 1 -C 6 -alkoxy)-; R 6 represents a hydrogen atom or a halogen atom or a group selected from: C 1 -C 6 -alkyl, C 1 -C 6 -alkoxy, C 3 -C 6 -cycloalkyl, C 3 -C 6 -cycloalkyloxy, C 1 -C 6 -haloalkyl, C 1 -C 6 -haloalkoxy and cyano; R 7 represents a hydrogen atom; R 8 represents a hydrogen atom; R 9 represents a hydrogen atom or a group selected from: C 1 -C 6 -alkyl and C 3 -C 6 -cycloalkyl; R 10 and R 11 are independently of each other selected from: hydrogen and C 1 -C 6 -alkyl; or R 10 and R 11 together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocycloalkyl; said 4-to 6-membered heterocycloalkyl being optionally substituted with one substituent selected from: C 1 -C 3 -alkyl, C 1 -C 3 -haloalkyl, C 1 -C 3 -alkoxy, C 1 -C 3 -haloalkoxy, amino, hydroxy, halogen and cyano; or said 4-to 6-membered heterocycloalkyl being optionally substituted with two halogen atoms; or a stereoisomer, an N-oxide, a hydrate, a solvate, or a salt thereof, or a mixture of same. R 1 represents a halogen atom or a group selected from: C 1 -C 6 -alkyl, C 3 -C 6 -cycloalkyl, C 1 -C 6 -alkoxy, C 3 -C 6 -cycloalkyloxy, C 1 -C 6 -haloalkyl, C 1 -C 6 -haloalkoxy, cyano, (C 1 -C 6 -alkyl)-S-, (C 1 -C 6 -alkyl)-S(=O)-, (C 1 -C 6 -alkyl)-S(=O) 2 -, (C 1 -C 6 -haloalkyl)-S-, (C 1 -C 6 -haloalkyl)-S(=O)-, (C 1 -C 6 -haloalkyl)-S(=O) 2 -, -C(=O)OR 9, -C(=O)N(R 10)R 11 and -N(R 10)R 11; R 2 represents a hydrogen atom; R 3 represents a hydrogen atom; R 4 represents a hydrogen atom or a halogen atom; R 5 represents a group selected from: -C(=O)OR 9, R 9 OC(=O)-(C 1 -C 6 -alkyl)-, R 9 OC(=O)-(C 2 -C 6 -alkenyl)-, R 9 OC(=O)-(C 1 -C 6 -alkoxy)-, -C(=O)N(R 10)R 11, R 10 (R 11)NC(=OHC 1 -C 6 -alkyl)-, R 10 (R 11)NC(=O)-(C 2 -C 6 -alkenyl)- and R 10 (R 11)NC(=O)-(C 1 -C 6 -alkoxy)-; R 6 represents a hydrogen atom or a halogen atom or a group selected from: C 1 -C 6 -alkyl, C 1 -C 6 -alkoxy, C 3 -C 6 -cycloalkyl, C 3 -C 6 -cycloalkyloxy, C 1 -C 6 -haloalkyl, C 1 -C 6 -haloalkoxy and cyano; R 7 represents a hydrogen atom; R 8 represents a hydrogen atom; R 9 represents a hydrogen atom or a group selected from: C 1 -C 6 -alkyl and C 3 -C 6 -cycloalkyl; R 10 and R 11 are independently of each other selected from: hydrogen and C 1 -C 6 -alkyl; R 10 and R 11 together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocycloalkyl; said 4-to 6-membered heterocycloalkyl being optionally substituted with one substituent selected from: C 1 -C 3 -alkyl, C 1 -C 3 -haloalkyl, C 1 -C 3 -alkoxy, C 1 -C 3 -haloalkoxy, amino, hydroxy, halogen and cyano; or said 4-to 6-membered heterocycloalkyl being optionally substituted with two halogen atoms;