Compounds of formula (I), or a salt or prodrug thereof, wherein R represent hydrogen or C.sub.1-6 alkyl; Q represents a moiety of formula Qa or Qb; they are antagonists of dopamine receptor subtypes within the brain, having a selective affinity for the dopamine D.sub.4 receptor subtype over other dopamine receptor subtypes, and are accordingly of benefit in the treatment and/or prevention of psychotic disorders such as schizophrenia whilst manifesting fewer side-effects than those associated with classical neuroleptic drugs. ##STR1##
公式(I)的化合物,或其盐或前药,其中R代表氢或C.sub.1-6烷基;Q代表公式Qa或Qb的基团;它们是大脑内
多巴胺受体亚型的拮抗剂,具有对
多巴胺D.sub.4受体亚型的选择亲和力,优于其他
多巴胺受体亚型,并且因此对治疗和/或预防精神分裂症等精神障碍有益,同时表现出比与经典神经阻滞药物相关的副作用更少。