Patent ID: 8680071

Claim:
A compound of Formula I: or a pharmaceutically acceptable salt, a stereoisomeric, tautomeric or polymorphic form thereof, wherein; R is a moiety derivable by removal of a hydrogen from a hydroxy group of an antiviral drug; X is O or S; Q is OR 4 , SR 4 or NR 5 R 6 ; each E is independently CR 7 R 8 ; each n is 1 or 2; R 1 and R 2 are selected as follows: i) R 1 and R 2 are each independently hydrogen, alkyl, alkenyl, alkynyl, aryl, aralkyl, cycloalkyl, cycloalkenyl, alkylheterocyclyl or alkylheteroaryl; ii) R 1 and R 2 together with the nitrogen atom on which they are substituted form a 3-7 membered heterocyclic or heteroaryl ring; or iii) R 1 is hydrogen, alkyl or cycloalkyl, and R 2 is (G) m C(O)Q 1 , wherein Q 1 is OR 4 , SR 4 or NR 5 R 6 ; each G is independently CR 7 R 8 ; and each m is 1 or 2; R 3 and R 4 are each independently hydrogen, alkyl, alkenyl, alkynyl, aryl, aralkyl, cycloalkyl or cycloalkenyl; R 5 and R 6 are selected as follows: i) R 5 and R 6 are each independently hydrogen, alkyl, alkenyl, alkynyl, aryl, aralkyl, cycloalkyl or cycloalkenyl; or ii) R 5 and R 6 together with the nitrogen atom on which they are substituted form a 3-7 membered heterocyclic or heteroaryl ring; and R 7 and R 8 are selected as follows: i) R 7 and R 8 are each independently hydrogen, alkyl, alkenyl, alkynyl, aryl, aralkyl, cycloalkyl, cycloalkenyl, alkylheterocyclyl or alkylheteroaryl, wherein alkyl is optionally substituted by alkoxy; or ii) R 7 and R 8 together with the carbon atom to which they are attached form a 3-7 membered cycloalkyl ring; and wherein if R 2 is (G) m C(O)Q 1 , G is CR 7 R 8 ; m is 1, and one of R 7 or R 8 is hydrogen, the other of R 7 and R 8 is isobutyl.