Disclosed are compounds of formula (I) or the pharmaceutically acceptable salts thereof wherein: ##STR1## G represents a group of the formula (a), (b) or (c) 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; and W is optionally susbtituted aryl or heteroaryl. Compounds of the present invention demonstrate high affinity and selectivity in binding to the D.sub.3 receptor subtype.