Synthesis and evaluation of novel 1-(2-acylhydrazinocarbonyl)-cycloalkyl carboxamides as interleukin-1β converting enzyme (ICE) inhibitors

Novel 1-(2-acylhydrazinocarbonyl)cycloalkyl carboxamides were designed as peptidomimetic inhibitors of interleukin-1β converting enzyme (ICE). A short synthesis was developed and moderately potent ICE inhibitors were identified (IC50 values <100 nM). Most of the synthesized examples were selective for ICE versus the related cysteine proteases caspase-3 and caspase-8, although several dual-acting inhibitors of ICE and caspase-8 were identified. Several of the more potent ICE inhibitors were also shown to inhibit IL-1β production in a whole cell assay (IC50 < 500 nM).