Synthesis and evaluation of novel prodrugs of caspase inhibitors.

A novel type of caspase inhibitor prodrug that improves systemic exposure after oral administration in rats has been designed. Such a prodrug, based on a 6,6a-dihydrofuro[3,2-d]oxazol-5(3aH)-one motif, has the advantage of rapidly liberating the active inhibitor without producing any cleavage by-product. Prodrugs 6-8, are synthesised in a high yielding one-step transformation from the active parents with high diastereomeric excess.