Disclosed are novel substituted heterocyclic derivatives having the structure of Formula I: ##STR00001## The compounds are useful for the treatment of various disease states, in particular cardiovascular diseases such as atrial and ventricular arrhythmias, intermittent claudication, Prinzmetal's (variant) angina, stable and unstable angina, exercise induced angina, congestive heart disease, diabetes, and myocardial infarction.
