M. Napoletano et al., STEREOSELECTIVE SYNTHESIS AND EVALUATION OF ALL STEREOISOMERS OF Z4349, A NOVEL AND SELECTIVE MU-OPIOID ANALGESIC, Bioorganic & medicinal chemistry letters, 5(6), 1995, pp. 589-592
A stereoselective synthesis of 1 was devised in order to obtain all 12
possible isomers. The pharmacological data clearly show a highly ster
eochemical requirement for the affinity and selectivity towards the mu
-receptor and the related analgesic activity.