Patent ID: 8207208

Claim:
A compound having the general formula: wherein R is selected from the group consisting of Y is selected from the group consisting of 1) R 5 , 2) —C(R 1 R 2 )(C(R 3 R 4 )) 0-1 Y 1 R 5 , and 3) —C(R 1 R 2 )—O—Y 1 R 5 , R 1 , R 2 , R 3 and R 4 are independently selected from the group consisting of hydrogen and C 1-4 alkyl; and R 5 is selected from the group consisting of Y 1 is selected from the group consisting of —C(O)—O— and —P(O)(OR 6 )—O—; and R 6 is hydrogen or CH 3 , or a pharmaceutically acceptable salt thereof.