The present invention provides a genus of polycyclic pyrazines of formula (I): wherein A and B are independently substituted or unsubstituted 5- or 6- membered heterocycloalkyl, or substituted or unsubstituted 5- or 6- membered heteroaryl, W1 is W2is —CH═, —NH—, —N═, —S—, or —O—; Z1 is Z2 is —CH═, —NH—, —N═, —S—, or —O—; Y is a bond, —CH═N—NH—, —NH—CH2, or —NR5—; s and t are independently integers from 1 to 4; and the substituents R1, R2A, R2B and R3 are as defined in the specification for compounds of formula (I). The polycyclic pyrazine compounds are useful as modulators of potassium ion channels in both therapeutic and diagnostic methods.