Disclosed are compounds of the class of isoquinolines substituted at the 1-position by an amino function bearing a hydroxy-alkyl nitrate moiety, e.g., 1-(5-hydroxypentyl)-amino-6,7-methylene-dioxyisoquinoline nitrate. The compounds have various pharmacological activities in animals and are useful, for example, as anti-hypertensive agents, anti-anginal agents and in the treatment of shock. Also disclosed are the corresponding hydroxy intermediates which are useful in preparation of the nitrates and also as hypotensive agents or as agents in the treatment of shock.