3-Bromoquinolin-8-amine acts as a reagent for the synthesis and structure activity relationship of 3-(arylsulfonyl)-8-(piperidin-4-yl amino)quinoline derivatives as 5-HT6 receptor antagonists for the treatment of Alzheimer''s disease and Schizophrenia. Also acts as a reagent for the synthesis of certain 8-aminoquinolines and antimalarias.