Caspase inhibitors and uses thereof

A method for treating a disease in a patient that is alleviated by treatment with a caspase inhibitor, which method comprises administering to a patient in need of such a treatment a therapeutically effective amount of a compound of formula I:

• 69
• wherein:
• Ring A is an optionally substituted piperidine, tetrahydroquinoline or tetrahydroisoquinoline ring;
• R1 is hydrogen, CN, CHN2, R, or CH2Y;
• R is an optionally substituted group selected from an aliphatic group, an aryl group or an aralkyl group;
• Y is an electronegative leaving group;
• R2 is CO2H, CH2CO2H, or esters, amides or isosteres thereof;
• and
• R3 is hydrogen, an optionally substituted aryl group, an optionally substituted aralkyl group, or an optionally substituted C1-6 aliphatic group, R4 is an optionally substituted group selected from an aryl group or a heterocyclyl group, or R3 and R4 taken together with the nitrogen to which they are attached optionally form a substituted or unsubstituted monocyclic, bicyclic or tricyclic ring.