Patent ID: 7507828

Claim:
A compound having the formula or a pharmaceutically acceptable salt thereof, wherein: X represents independently for each occurrence O or S; Z represents a bond; R 9 is phenyl, naphthalenyl, pyridinyl, quinolinyl or isoquinolinyl; wherein R 9 is unsubstituted or substituted with one or more of the following groups: phenyl, -halo, —C 1 -C 6 alkyl, —O-(C 1 -C 6 alkyl), —OH, —NO 2, —OR′, —CN, —COOR′, —OC(O)R′, —NHR′, —N(R′) 2 , —NHC(O)R′ or —C(O)NHR′; R′ is independently H or unsubstituted —C 1 -C 6 alkyl; m is an integer ranging from 1-5; and n is an integer ranging from 1-5.