<P>PROBLEM TO BE SOLVED: To provide pro-drugs of caspase inhibitors that have an improved ability of crossing the blood-brain barrier and transmit brains and central nervous systems at therapeutically useful levels. <P>SOLUTION: This compound has a structure represented by formula I, wherein, X is -OR<SP>1</SP>or -N (R<SP>5</SP>)<SB>2</SB>; Y is halo, trifluorophenoxy, or tetrafluorophenoxy; and R<SP>1</SP>, R<SP>2</SP>, R<SP>3</SP>, R<SP>4</SP>and R<SP>5</SP>are each particularly defined. <P>COPYRIGHT: (C)2007,JPO&INPIT 
ESTER AND AMIDE DERIVATIVES OF 4-OXO-3-(1-OXO-1H-ISOQUINOLIN-2-YL ACETYLAMINO)-PENTANOIC ACID AND THEIR USE AS CASPASE INHIBITORS