9-[3-(4-Phenoxymethylpiperidino)-propyl]-adenines of the formula ##STR1## wherein R.sub.1 is a hydrogen atom or a lower alkyl radical,R.sub.2 is a hydrogen atom, a ower alkyl radical optionally substituted by hydroxyl, or a cycloalkyl radical, orR.sub.1 and R.sub.2 together with the nitrogen atom to which they are attached form a heterocyclic ring, andR.sub.3 is a hydrogen atom, a halogen atom, a lower alkyl radical or a lower alkoxy radical,In the form of the free base or a salt thereof, exhibit anti-allergic, anti-inflammatory, anti-oedematous and anti-hypertensive activity.