Compound of formula: its pharmaceutically acceptable salts, tautomers and/or solvates, wherein R 1 is CF 3, X is selected from among CH 2, NH, CHPh, CH 2 CH 2, CH 2 CHPh, CH=CH, CH 2 OCH 2, CH 2 NHCO, CH 2 NHCOCHPh and CH 2 NHCOCH 2, R 2, R 3, R 4 and R 5 are independently selected from among H, halogen and O-alkyl (C 1 -C 5), NH 2, NHR 6, CN, NO 2, OCF 3 and CO 2 R 6, R 6 is selected from among H and alkyl (C 1 -C 5), provided that that when X is CHPh, CH 2 CHPh or CH 2 NHCOCHPh, then R 2, R 3, R 4 and R 5 are H, for use for the treatment and/or prevention of a disease mediated by the CK-1 enzyme, wherein the disease mediated by CK-1 enzyme is a disease selected from among transoceanic syndrome, night shift worker sleep disorder, delayed sleep phase syndrome, advanced sleep phase disorder, Crohn's disease, ulcerative colitis, multiple sclerosis, encephalitis, myelitis, encephalomyelitis, vasculitis, arthritis, atherosclerosis, osteoarthritis, rheumatoid arthritis, neurological disorder, bipolar disorders, behavioural disorders, anxiety, depression, glaucoma, macular degeneration, retinitis pigmentosa, Alzheimer's disease, Parkinson's disease, postencephalitic Parkinsonism, Tourette syndrome, periodic limb movement pathologies, restless legs syndrome, Huntington's disease, progressive supranuclear palsy, Pick's disease, frontotemporal dementia, amyotrophic lateral sclerosis, muscular dystrophy, myotonic dystrophy and distal muscular dystrophy; cerebral palsy; Friedreich's ataxia, congenital myasthenic syndrome and myasthenia gravis; preferably the disease is selected from among depression, bipolar disorder, retinitis pigmentosa, Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis or frontotemporal dementia. its pharmaceutically acceptable salts, tautomers and/or solvates, wherein R 1 is CF 3, X is selected from among CH 2, NH, CHPh, CH 2 CH 2, CH 2 CHPh, CH=CH, CH 2 OCH 2, CH 2 NHCO, CH 2 NHCOCHPh and CH 2 NHCOCH 2, R 2, R 3, R 4 and R 5 are independently selected from among H, halogen and O-alkyl (C 1 -C 5), NH 2, NHR 6, CN, NO 2, OCF 3 and CO 2 R 6, R 6 is selected from among H and alkyl (C 1 -C 5), provided that that when X is CHPh, CH 2 CHPh or CH 2 NHCOCHPh, then R 2, R 3, R 4 and R 5 are H, for use for the treatment and/or prevention of a disease mediated by the CK-1 enzyme, wherein the disease mediated by CK-1 enzyme is a disease selected from among transoceanic syndrome, night shift worker sleep disorder, delayed sleep phase syndrome, advanced sleep phase disorder, Crohn's disease, ulcerative colitis, multiple sclerosis, encephalitis, myelitis, encephalomyelitis, vasculitis, arthritis, atherosclerosis, osteoarthritis, rheumatoid arthritis, neurological disorder, bipolar disorders, behavioural disorders, anxiety, depression, glaucoma, macular degeneration, retinitis pigmentosa, Alzheimer's disease, Parkinson's disease, postencephalitic Parkinsonism, Tourette syndrome, periodic limb movement pathologies, restless legs syndrome, Huntington's disease, progressive supranuclear palsy, Pick's disease, frontotemporal dementia, amyotrophic lateral sclerosis, muscular dystrophy, myotonic dystrophy and distal muscular dystrophy; cerebral palsy; Friedreich's ataxia, congenital myasthenic syndrome and myasthenia gravis; preferably the disease is selected from among depression, bipolar disorder, retinitis pigmentosa, Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis or frontotemporal dementia.