Synthesis and evaluation of thiazepines as interleukin-1β converting enzyme (ICE) inhibitors

The synthesis of a series of monocyclic ICE inhibitors is reported. A series of monocyclic thiazepine inhibitors of interleukin-1β converting enzyme (ICE) were synthesized in eight steps from commercially available intermediates. In vitro biological evaluation showed the thiazepines to be moderately potent ICE inhibitors, with the most active compound exhibiting an IC50 value of 30nM in an enzyme inhibition assay. Compounds of this class possessed good selectivity against the related enzymes caspase-3 and caspase-8.