This paper describes the design and synthesis of compounds belonging to a novel class of highly selective mammalian CD13 inhibitors. Racemic homologues of 3-amino-2-tetralone 1 were synthesised and evaluated for their ability to selectively inhibit the membrane-bound, zinc-dependent aminopeptidase-N/CD13 (EC 3.4. 11.2). Some of these novel non-peptidic compounds are potent, competitive inhibitors of the mammalian enzyme, with Ki values in ...