Patent ID: 8481495

Claim:
A compound of Formula (I): or a pharmaceutically acceptable salt thereof, wherein: X1, X2 and X3 are each independently O or S: R is selected from H; alkyl; substituted alkyl; alkenyl; substituted alkenyl; cycloalkyl; substituted cycloalkyl; aryl; substituted aryl; heteroaryl; or substituted heteroaryl; R1a and R1b are each independently selected from H; alkyl; or substituted alkyl; R2 is selected from H; alkyl; substituted alkyl; cycloalkyl; substituted cycloalkyl; heterocycloalkyl; substituted heterocycloalkyl; aryl; substituted aryl; heteroaryl; or substituted heteroaryl; R4 and R5 are each independently selected from H; alkyl; substituted alkyl; cycloalkyl; substituted cycloalkyl; aryl; substituted aryl; heterocycloalkyl; substituted heterocycloalkyl; heteroaryl; or substituted heteroaryl; or R4 and R5 together with the nitrogen to which they are attached represent heterocycloalkyl; or substituted heterocycloalkyl; R6 is selected from H; alkyl; substituted alkyl; alkoxy; substituted alkoxy; alkylsulfonyl; arylsulfonyl; cycloalkyl; substituted cycloalkyl; heterocycloalkyl; substituted heterocycloalkyl; aryl; substituted aryl; heteroaryl; or substituted heteroaryl; and R12 is selected from H or hydroxy.