Patent ID: 8729109

Claim:
A compound represented by Formula I, its individual enantiomers, its individual diastereoisomers, its individual tautomers or a pharmaceutically acceptable salt thereof wherein: R 1 is —C 6-10 aryl, —C 5-6 heterocycle, —C 3-8 cycloalkyl, —C 3-8 cycloalkenyl, —C 1-6 alkyl, or hydrogen; R 2 is —OPO 3 H 2 , carboxylic acid, —PO 3 H 2 , —C 1-6 alkyl, —S(O) 2 H, —P(O)(Me)OH, —OP(O)(OMe) 2 , —P(O)(H)OH, —OR 3 or —OP(O)(OMe)(OH); and R 3 is H or —C 1-3 alkyl.