A compound of formula (I), or a pharmaceutically acceptable salt thereof wherein n is 0-3; R and R are independently H (provided only one is H at the same time), -OH (provided R is other than hydrogen), CN, CH2CN, 2- or 4-CF3, CH2CF3, CH2CHF2, CH=CF2, (CH2)2CF3, ethenyl, 2-propenyl, OSO2CH3, OSO2CF3, SSO2CF3, COR , COOR , CON(R )2, SOxCH3 (where, x is 0-2), SOxCF3, O(CH2)xCF3, SO2N(R )2, CH=NOR , COCOOR , COCOON(R )2, C1-8 alkyls, C3-8 cycloalkyls, CH2OR , CH2(R )2, NR SO2CF3, NO2, halogen, a phenyl at positions 2, 3 or 4, thienyl, furyl, pyrrole, oxazole, thiazole, N-pyrroline, triazole, tetrazole or pyridine; R is hydrogen, CF3, CH2CF3, C1-C8 alkyl, C3-C8 cycloalkyl, C4-C9 cycloalkyl-methyl, C2-C8 alkenyl, C2-C8 alkynyl, 3,3,3-trifluoropropyl, 4,4,4-trifluorobutyl, -(CH2)m-R (where m is 1-8), CH2SCH3 or a C4-C8 alkyl bonded to said nitrogen and one of its adjacent carbon atoms inclusive to form a cyclic structure; R is independently hydrogen, CF3, CH2CF3, C1-C8 alkyl, C3-C8 cycloalkyl, C4-C9 cycloalkyl-methyl, C2-C8 alkenyl, C2-C8 alkynyl, 3,3,3-trifluoropropyl, 4,4,4-trifluorobutyl, -(CH2)m-R where m is 1-8; R is phenyl, phenyl (substituted with a CN, CF3, CH2CF3, C1-C8 alkyl, C3-C8 cycloalkyl, C4-C9 cycloalkyl-methyl, C2-C8 alkenyl, C2-C8 alkynyl), 2-thiophenyl, 3-thiophenyl, -NR CONR R , or -CONR R ; R and R are independently hydrogen, C1-C8 alkyl, C3-C8 cycloalkyl, C4-C9 cycloalkylmethyl, C2-C8 alkenyl or C2-C8 alkynyl; and with the proviso that when R is 2-CN or 4-CN, R is H, R is n-Pr and n is 1 or 3 then such compound is a pure enantiomer. The formula (I) compounds possess selective pharmacological properties and are useful in treating central nervous system disorders related to dopamine receptor activity including depression symptoms, geriatric disorders in the improvement of mental and motor functions, schizophrenia, narcolepsy, MBD, obesitas, and disturbances of sexual functions and impotence.