| abstract |
Compounds of Formula I: ##STR1## where R 5 is a group selected from Formulae (a), (b), (c) and (d): ##STR2## and the pharmaceutically acceptable salts and N-oxides thereof, are α 1 -adrenergic receptor antagonists useful for the treatment of diseases involving directly or indirectly an obstruction of the lower urinary tract, such as benign prostatic hyperplasia. |