| abstract |
Process for the preparation of cyclic hexapeptide somatostatin analogs, drug-acting substances, of the formula: Wherein R 1 and R 2 are different and represent a benzyl radical optionally substituted by one or two lower alkyl, halogen, hydroxy, amino, nitro or lower alkoxy radicals, a lower alkyl radical optionally substituted by a penta or hexaheterocyclic ring; R3 represents the 3-indolylmethyl radical, optionally substituted by methoxy or fluoro; R4 represents one of the methyl, ethyl, hydroxymethyl or hydroxyethyl radicals; R5 represents a methyl radical, R6 represents a methylene radical or together with the N atom form a pentaheterocycle. |