The present invention relates to novel substituted methyl-amines, serotonin 5-HT6 receptor antagonists, to active components, pharmaceutical compositions, method for prophylaxis and treatment of CNS diseases and “molecular tools”, in which novel substituted methyl-amines represent compounds of the general formula 1 and their crystalline forms and pharmaceutically acceptable salts, wherein: W represents benzene, naphthalene, indolizine, quinoline or oxazole cycle; R1=H, F, Cl; R2 represents hydrogen, fluoro, methyl, phenyl, thienyl, furan-2-yl, pyridyl, piperazin-1-yl or 4-methylpiperazin-1-yl; R3 represents cyclopropyl or optionally substituted methyl; with the exception of the compounds in which W simultaneously represents oxazole cycle and R2=phenyl or pyridyl.