Patent ID: 8916708

Claim:
A compound of formula (I), or a pharmaceutically acceptable salt thereof: wherein; R 1 is a radical of formula (IB): wherein R 4b is C 1 -C 6 alkyl, C 3 -C 6 cycloalkyl, phenyl which is optionally substituted with at least one substituent selected from the group consisting of halo, —O-benzyl, hydroxyl, and hydroxyl(C 1 -C 6 )alkylthio; Y is —O—; A is a divalent radical of formula (Va) in either orientation; wherein t is 1, 2, or 3; R 2 is a radical of formula (IIIa), (IIIb), or (IIIc): wherein q is 0,1,2or 3; R 7 is —CH 3 ; —C 2 H 5 ; —CH 2 OH, —CH 2 SCH 3 ; —SCH 3 or —SC 2 H 5 ; R 8 is —CH 3 or —C 2 H 5 ; and each occurrence of R 6 is independently H, C 1 —C 6 alkyl, hydroxy or halo.