Radioligands and their use for identifying potassium channel modulators

A compound of formula (I)

• wherein
• n is an integer of 0-1;
• m is an integer of 1-2;
• provided that when n is 1, then m is 1;
• A is selected from the group consisting of C(O) and S(O)2;
• D is selected from the group consisting of O, S and CR2R3;
• Z is selected from the group consisting of O and S;
• R1 is selected from the group consisting of alkyl, cyano, haloalkoxy, haloalkyl, halogen and nitro;
• and
• R2, R3, R4, R5, R6 and R7 are each independently selected from the group consisting of hydrogen and alkyl;
• provided that when A is S(O)2;
• then D is CR2R3;
• and
• further provided that when D is S;
• then n is 1 and A is C(O).