Cardiotonic ‘C’ Ring Modified Isomazole Analogues

Abstract
Isomazole analogues which have achiral electron withdrawing substituents at the 4′‐position and analogues with heterocyclic ‘C’ rings have been synthesized and evaluated as inotropic agents. It was found that pyridyl could replace phenyl in the ‘C’ ring without loss of activity. The 4′‐methylsulphonyl, ‐cyano, ‐carboxamido, and acetyl analogues had similar inotropic potencies to Isomazole whilst displaying superior cardiovascular profiles in in vivo studies.