Indoleamine derivatives of formula (IA), wherein R1 represents benzyl unsubstituted or substituted with halogen atom, -OH, or C1-C3-alkyl phenylsulphonyl unsubstituted or substituted in the phenyl ring with halogen atom, -OH or C1-C3-alkyl G1 represents phenoxyalkyl, heteroaryloxyalkyl- or heterocyclyloxyalkyl-piperazine moiety and pharmaceutically acceptable salts and solvates thereof. The compounds may be useful for the treatment and/or prevention of the central nervous system disorders.