Abstract: The invention relates to new peptide derivatives which act on the central nervous system and correspond to the general formula (I),X--Y--W--NH.sub.2 (I)whereinX is L-pyroglutamyl, D-pyroglutamyl, L-2-keto-imidazolidine-4-carbonyl, L-6-keto-pipecolyl, L-thiazolidine-4-carbonyl, L-prolyl or orotyl group,Y is L-leucyl, L-norvalyl or L-histidyl group, andW is L-prolyl, D-prolyl, L-thiazolidine-4-carbonyl, L-pipecolyl, L-homoprolyl, L-leucyl, L-isoleucyl, L-methionyl or D-pipecolyl group, orthe W-NH.sub.2 group stands for pyrrolidyl or piperidyl group, with the proviso that if X is L-pyroglutamyl and Y is L-histidyl group, W is other than L-prolyl group, and pharmaceutically acceptable complexes thereof.These compounds are prepared by methods commonly applied in the peptide chemistry.

Abstract: The invention relates to new peptide derivatives which act on the central nervous system and correspond to the general formula (I),Glp--X--Y--NH--A (I)whereinX is L-norleucyl, L-leucyl, L-norvalyl, D-leucyl, L-prolyl, L-2-aminobutyryl, L-valyl, L-threonyl, L-isoleucyl, L-2-aminodecanoyl, L-cyclohexylalanyl or L-tert.-butyl-seryl group andY is L-prolyl group, orX is L-histidyl group andY is L-homoprolyl or D-pipecolyl group, furthermoreA is hydrogen, a C.sub.1-10 alkyl group or a C.sub.1-3 alkyl group having a dimethylamino substituent,with the proviso that if X is L-leucyl group, A is other than hydrogen, and pharmaceutically acceptable complexes thereof.These compounds are prepared by methods commonly applied in the peptide chemistry.

Abstract: A process for the preparation of L-aspartyl-(O-sulfato-L-tyrosyl)-L-methionyl-glycyl-L-tryptophyl-L-methion yl-L-aspartyl-L-phenylalanine amide, which comprises treating the protected octapeptide amide of the general formula (II) ##STR1## wherein X is BOC, Cbz or Ddz,Y is O.sup.t Bu, OBzl or OH andW is O.sup.t Bu, OBzl or OH,in the presence of an ether with an excess of the complex compound of sulfur trioxide and a tertiary amine containing at least one alkyl group, converting the obtained sulfate ester of the protected octapeptide amide into an alkali metal salt and simultaneously removing the formyl group from the tryptophan unit by reacting the sulfate ester with an alkali metal hydroxide, and then splitting off the remaining protective groups by acidolysis.