Derivatives of piperazina for rent oxindols.

3-alkyl indole-2-one derivatives of general formula (I), ** see formula ** in which R 1 represents hydrogen, halogen, alkyl of 1 to 7 carbon atoms; R 2 and R 3 represent hydrogen; R 4 is hydrogen or halogen; R 5 represents halogen or trifluoromethyl; m is 4; and pharmaceutically acceptable acid addition salts thereof.