This disclosure describes novel substituted .omega.-aroyl(propionyl or butyryl)-L-prolines and the esters and cationic salts thereof which are useful as hypotensive agents in mammals.
base-catalyzed cascade nucleophilic/aza-Michael addition reaction of N-alkoxy β-oxo-acrylamides with isocyanates has been developed to afford various highly functionalized hydantoin derivatives in 80–98% yields under mild reaction conditions. The intriguing features of this method include metal-free reaction conditions, low catalyst loading, broad substrate scope and short reaction time.