Non-medical method of modulating of transient receptor potential channel melastatin member 8 (TRPM8) comprising bringing the receptor into contact with a compound of formula (la), a salt or solvate thereof wherein XisC, R 3 is selected from hydrogen, C 1 -C 6 alkyl, C 1 -C 7 alkyl substituted with one or two OH groups, C 3 -C 7 cycloalkyl, C 3 -C 7 cycloalkyl substituted with one or two OH groups, C 5 -C 7 cycloalkenyl, C 5 -C 7 cycloalkenyl substituted with one, two or three C 1 -C 3 alkyl groups, and phenyl; R 1 is selected from hydrogen, C 1 -C 6 alkyl, C 1 -C 7 alkyl substituted with one or two OH groups, C 3 -C 7 alkenyl, phenyl optionally substituted with up to five substituents selected from the group consisting of halogen, C≡N, NO 2, C 1 -C 6 alkyl, C 1 -C 6 alkyl comprising up to 5 halogen atoms, C 1 -C 6 alkyloxy, C 1 -C 6 alkyloxy comprising up to 5 halogen atoms, C 3 -C 7 cycloalkyl, -C O-R 10 wherein R 10 is selected from hydrogen and C 1 -C 3 alkyl, and -SR 11 wherein R 11 is selected from hydrogen and C 1 -C 3 alkyl, naphthyl optionally substituted with up to five substituents selected from the group consisting of halogen, C≡N, NO 2, C 1 -C 6 alkyl, C 1 -C 6 alkyl comprising up to 5 halogen atoms, C 1 -C 6 alkyloxy, C 1 -C 6 alkyloxy comprising up to 5 halogen atoms, C 3 -C 7 cycloalkyl, -C O-R 10 wherein R 10 is selected from hydrogen and C 1 -C 3 alkyl, and -SR 11 wherein R 11 is selected from hydrogen and C 1 -C 3 alkyl, and C 5 -C 10 mono- or bicyclic aryl wherein 1 or 2 C-atoms are replaced by a hetero atom independently selected from sulfur, nitrogen, and oxygen, optionally substituted with up to three substituents selected from the group consisting of halogen, C≡N, NO 2, C 1 -C 6 alkyl, C 1 -C 6 alkyl comprising up to 5 halogen atoms, C 1 -C 6 alkyloxy, C 1 -C 6 alkyloxy comprising up to 5 halogen atoms, C 3 -C 7 cycloalkyl, -C O-R 10 wherein R 10 is selected from hydrogen and C 1 -C 3 alkyl, and -SR 11 wherein R 11 is selected from hydrogen and C 1 -C 3 alkyl; R 2 is selected from hydrogen and methyl; R 4, R 5, and R 7 are independently selected from hydrogen and C 1 -C 6 alkyl; R 6 is selected from hydrogen, C 1 -C 6 alkyl, and C 3 -C 7 cycloalkyl; R 8 and R 9 are independently selected from hydrogen, and C 1 -C 6 alkly, or R 8 and R 9 form together with the C-atom to which they are attached a 3, 4, 5, 6, or 7- membered cycloalkyl ring. XisC, R 3 is selected from hydrogen, C 1 -C 6 alkyl, C 1 -C 7 alkyl substituted with one or two OH groups, C 3 -C 7 cycloalkyl, C 3 -C 7 cycloalkyl substituted with one or two OH groups, C 5 -C 7 cycloalkenyl, C 5 -C 7 cycloalkenyl substituted with one, two or three C 1 -C 3 alkyl groups, and phenyl; R 1 is selected from hydrogen, C 1 -C 6 alkyl, C 1 -C 7 alkyl substituted with one or two OH groups, C 3 -C 7 alkenyl, phenyl optionally substituted with up to five substituents selected from the group consisting of halogen, C≡N, NO 2, C 1 -C 6 alkyl, C 1 -C 6 alkyl comprising up to 5 halogen atoms, C 1 -C 6 alkyloxy, C 1 -C 6 alkyloxy comprising up to 5 halogen atoms, C 3 -C 7 cycloalkyl, -C O-R 10 wherein R 10 is selected from hydrogen and C 1 -C 3 alkyl, and -SR 11 wherein R 11 is selected from hydrogen and C 1 -C 3 alkyl, naphthyl optionally substituted with up to five substituents selected from the group consisting of halogen, C≡N, NO 2, C 1 -C 6 alkyl, C 1 -C 6 alkyl comprising up to 5 halogen atoms, C 1 -C 6 alkyloxy, C 1 -C 6 alkyloxy comprising up to 5 halogen atoms, C 3 -C 7 cycloalkyl, -C O-R 10 wherein R 10 is selected from hydrogen and C 1 -C 3 alkyl, and -SR 11 wherein R 11 is selected from hydrogen and C 1 -C 3 alkyl, and C 5 -C 10 mono- or bicyclic aryl wherein 1 or 2 C-atoms are replaced by a hetero atom independently selected from sulfur, nitrogen, and oxygen, optionally substituted with up to three substituents selected from the group consisting of halogen, C≡N, NO 2, C 1 -C 6 alkyl, C 1 -C 6 alkyl comprising up to 5 halogen atoms, C 1 -C 6 alkyloxy, C 1 -C 6 alkyloxy comprising up to 5 halogen atoms, C 3 -C 7 cycloalkyl, -C O-R 10 wherein R 10 is selected from hydrogen and C 1 -C 3 alkyl, and -SR 11 wherein R 11 is selected from hydrogen and C 1 -C 3 alkyl; R 2 is selected from hydrogen and methyl; R 4, R 5, and R 7 are independently selected from hydrogen and C 1 -C 6 alkyl; R 6 is selected from hydrogen, C 1 -C 6 alkyl, and C 3 -C 7 cycloalkyl; R 8 and R 9 are independently selected from hydrogen, and C 1 -C 6 alkly, or R 8 and R 9 form together with the C-atom to which they are attached a 3, 4, 5, 6, or 7- membered cycloalkyl ring.