Use of N-(2-((3-(4-bromophenyl)-2-propenyl)amino)ethyl)-5-isoquinolinesulfonamide (I) to prepare a medicament for the treatment of hyperpigmentary disorders. ACTIVITY : Cytostatic; Dermatological. MECHANISM OF ACTION : Tyrosine kinase inhibitor. The tyrosine kinase inhibiting activity of (I) was tested. The result showed that (I) had a percentage activation of 120.