The present invention relates to novel compounds of formula (I) or a salt thereof: wherein R1 is a 5-membered heteroaryl group, optionally fused with a 6-membered hetero or carbocycle; such 5 or 11-membered system, may be optionally substituted by 1, 2, 3 or 4 substituents selected from the group consisting of: halogen, cyano, C1-4alkyl, haloC1-4alkyl, C1-4alkoxy, C1-4alkanoyl, haloC1-4alkoxy and SF5; and n is 1 or 2; their use in therapy, as modulators of dopamine D3 receptors, e.g. to treat drug dependency, as antipsychotic agents, to treat obsessive compulsive spectrum disorders, or premature ejaculation.