Disclosed are compounds of the formula ##STR1## or the pharmaceutically acceptable salts thereof wherein: G represents a group of the formula ##STR2## where R.sub.a and R.sub.b represent hydrogen, or organic or inorganic substituents;A is an optionally substituted alkylene;R.sub.1, R.sub.2, R.sub.3, R.sub.4 represent organic or inorganic substituents;R.sub.5 is hydrogen or lower alkyl;R.sub.6 and R.sub.7 independently represent hydrogen, lower alkyl; or together form a ring of 5-8 members;Z is nitrogen or carbon; andW is optionally substituted aryl or heteroaryl. Compounds of the present invention demonstrate high affinity and selectivity in binding to the D.sub.3 receptor subtype.