This invention relates to a process for synthesizing heterocyclic pharmaceutical compound which binds to the CXCR4 chemokine receptor. In one embodiment, the process comprises: a) reacting a 5,6,7,8-tetrahydroquinolinylamine and an alkyl aldehyde bearing a phthalimide or a di-tertiary-butoxycarbonyl (di-BOC) protecting group to form an imine; b) reducing the imine to form a secondary amine; c) reacting the secondary amine with a haloalkyl substituted heterocyclic compound, to form a phthalimido-protected or di-tert-butoxycarbonyl protected tertiary amine; and d) hydrolyzing the protected amine to obtain a compound having Formula I' ##STR00001##