The compounds are N-(2,3,4-trimethoxybenzyl)piperazines N'-substituted by a radical containing a sulfonamide group, and pharmaceutically tolerable salts thereof, useful for treating myocardial ischaemic pathologies, cerebral vascular accident and manifestations of deficiency associated with chronic cerebral circulatory disorders. A compound disclosed is : N-benzyl-N-3,3-dimethyl-4-[4-(2,3,4-trimethoxybenzyl) piperazin-1-yl]butyl}-(isoquinolin-5-yl)sulfonamide and its fumarate.