Certain benzothiazine dioxide endothelin antagonists and processes for their preparation

摘要

The instant invention is a series of benzothiazine dioxides, or a pharmaceutically acceptable salt thereof, which are potent endothelin A antagonists with profound in vitro activity, and improved syntheses for the Formula 1The compounds are useful in treating elevated levels of endothelin, essential renovascular malignant and pulmonary hypertension, cerebral infarction, cerebral ischemia, congestive heart failure, and subarachnoid hemorrhage.