| abstract |
This invention provides compounds of formula (I): wherein Z is oxygen or sulfu; R1 is hydrogen, -CHN¿2?, R, CH2OR, CH2SR, or -CH2Y; --- next to R?3¿ represents a single or double bond; Y is an electronegative leaving group; R2 is CO¿2?H, CH2CO2H, or esters, amides or isosteres thereof; R?3¿ is a group capable of fitting into the S2 subsite or a caspase enzyme; R4 is hydrogen or C¿1-6?alkyl or R?3and R4¿ taken together form a ring; Ring A and Ring B are each heterocyclic rings, and R and R5 are as described in the specification. The compounds are effective inhibitors of apoptosis and IL-1β secretion. |