Use of isatin derivatives as ion channel activating agents

A method of treatment or alleviation of a disease or disorder or condition of a living animal body, including a human, which disorder or disease or condition is responsive to activation of SKCa and/or IKCa channels, comprising the step of administering to such a living animal body, including a human, in need thereof a therapeutically effective amount of an isatin compound represented by the formula

• 13
• or a pharmaceutically acceptable salt or an oxide or a hydrate thereof, wherein,
• R1 represents hydrogen;
• an alkyl group;
• a cycloalkyl group;
• an acyl group;
• a phenyl or a benzyl group, which phenyl and benzyl groups are unsubstituted or are substituted one or more times with substituents selected from halogen, —NO2, —CN, —CF3, alkyl, cycloalkyl, hydroxy, and alkoxy;
• a group of the formula —CH2CN;
• a group of the formula —CH2CO2R′, wherein R′ represents hydrogen or alkyl;
• a group of the formula —CH2CONRIVRV, wherein RIV and RV independently represents hydrogen, alkyl, phenyl or benzyl, which phenyl and benzyl groups are unsubstituted or are substituted one or more times with halogen and/or alkyl, or RIV and RV together with the N-atom to which they are attached form a heterocyclic 4 to 7 membered monocyclic group, which heterocyclic group are unsubstituted or are substituted one or more times with substituents selected from the group consisting of halogen, alkyl, cycloalkyl, alkyloxy, cycloalkyloxy, phenyl or benzyl;
• or a group of the formula —CH2C(═NOH)NH2;
• R2 represents hydrogen;
• an alkyl group;
• a cycloalkyl group;
• a group of the formula —CH2CO2R′, wherein R′ represents hydrogen or an alkyl group;
• a phenyl or a benzyl group, which phenyl and benzyl groups are unsubstituted or are substituted one or more times with substituents selected from halogen, —NO2, —CN, —CF3, alkyl, cycloalkyl, hydroxy, and alkoxy;
• and
• R3, R4, R5, and R6 independently of each another represents hydrogen;
• halogen;
• —NO2;
• —CN;
• —CF3;
• an alkyl group;
• an alkoxy group;
• a phenyl or a benzyl group, which phenyl and benzyl groups are unsubstituted or are substituted one or more times with substituents selected from halogen, —NO2, —CN, —CF3, alkyl, cycloalkyl, hydroxy, and alkoxy;
• or a group of the formula —SO2NR″R′″, wherein R″ and R′″ independently of each another represents hydrogen or an alkyl group;
• or R5 and R6 are as defined above, and R3 and R4 together form an additional 4 to 7 membered fused ring, which fused ring may be aromatic, saturated or partially saturated, and which fused ring are unsubstituted or are substituted one or more times with substituents selected from the group consisting of halogen, —NO2, —CN, —CF3, and a group of the formula —SO2NR″R′″, wherein R″ and R′″ independently of each another represents hydrogen or an alkyl group.