The present invention relates to novel compounds of formula (I) or a pharmaceutically acceptable salt thereof: wherein €¢ G is phenyl and (R 1 ) p is 4-trifluoromethyl €¢ R 2 is hydrogen €¢ R 3 is methyl €¢ R 4 is 4-pyridazinyl processes for their preparation, intermediates used in these processes, pharmaceutical compositions containing them and their use in therapy, as modulators of dopamine D 3 receptors, e.g. to treat drug dependency or as antipsychotic agents.