11 621 63 123451 661 61 627Substituted indole derivatives of formula (I) wherein the radicals have e. g. the following meaning: R is hydrogen C alkyl R is hydrogen C alkyl or cycloC alkyl R is OR R is hydrogen or halogen R is hydrogen C alkyl R is hydrogen C alkyl R is hydrogen or C alkyl X is a group C(O)CH or CH=CH R is hydrogen are potent inhibitors of Abeta peptide polymerization and can be used for the treatment of e.g. Alzheimers disease or ocular disorders.