An efficient asymmetric synthesis of the potent β-blocker ICI-118,551 allows the determination of enantiomer dependency on biological activityWe would like to dedicate this paper to the memory of Sir James Black who instigated this work as part of a larger βAR study at UCL.Electronic supplementary information (ESI) available: Full experimental details are provided. See DOI: 10.1039/c0cc00142b

A highly efficient, practical and flexible two-step asymmetric synthesis of the β2-selective β-blocker ICI 118,551 is reported, allowing an unambiguous determination of the dependency of biological activity with optical activity, revealing the S,S-enantiomer to be the most potent. [ABSTRACT FROM AUTHOR]