Abstract: The invention provides compounds of the formula: wherein B is a nucleobase selected from the groups (a) to (d): and the other variables are as defined in the claims, which are of use in the treatment or prophylaxis of hepatitis C virus infection, and related aspects.

Abstract: Compounds of the formula I wherein R2a and R2b are independently H, halo, C1-C4alkyl, C1-C4haloalkyl or C1-C4alkoxy, or R2a and R2b together with the carbon atom to which they are attached form a C3-C6cycloalkyl; R3 is a C5-C10 alkyl, optionally substituted with 1-3 substituents independently selected from halo, C1-C4haloalkyl, C1-C4alkoxy, C1-C4haloalkoxy; or R3 is a C2-C4alkyl chain with at least 2 chloro or 3 fluoro substituents; or R3 is C3-C7cycloalkylmethyl, optionally substituted with 1-3 substituents independently selected from C1-C4alkyl, halo, C1-C4haloalkyl, C1-C4alkoxy, C1-C4haloalkoxy; R4 is C1-C6alkyl, C1-C6haloalkyl, C1-C6alkoxy, C1-C6haloalkoxy, C1-C6alkylamino, C1-C6dialkylamino or; R4 is Het or Carbocyclyl, either of which is optionally substituted with 1-3 substituents R4 is Het, carbocyclyl, C1-C6alkyl, C1-C6haloalkyl, C1-C6alkoxy or C1-C6haloalkoxy; n is 1, 2 or 3; for the use in the prophylaxis or treatment of a disorder characterised by inappropriate expression or activation of cat

Abstract: Compounds of the formula I wherein R2a and R2b are independently H, halo, C1-C4alkyl, C1-C4haloalkyl or C1-C4alkoxy, or R2a and R2b together with the carbon atom to which they are attached form a C3-C6cycloalkyl; R3 is a C5-C10 alkyl, optionally substituted with 1-3 substituents independently selected from halo, C1-C4haloalkyl, C1-C4alkoxy, C1-C4haloalkoxy; or R3 is a C2-C4alkyl chain with at least 2 chloro or 3 fluoro substituents; or R3 is C3-C7cycloalkylmethyl, optionally substituted with 1-3 substituents independently selected from C1-C4alkyl, halo, C1-C4haloalkyl, C1-C4alkoxy, C1-C4haloalkoxy; R4 is C1-C6alkyl, C1-C6haloalkyl, C1-C6alkoxy, C1-C6haloalkoxy, C1-C6alkylamino, C1-C6dialkylamino or; R4 is Het or Carbocyclyl, either of which is optionally substituted with 1-3 substituents R4 is Het, carbocyclyl, C1-C6alkyl, C1-C6haloalkyl, C1-C6alkoxy or C1-C6haloalkoxy; n is 1, 2 or 3; for the use in the prophylaxis or treatment of a disorder characterised by inappropriate expression or activation of ca

Abstract: Compounds of the formula I wherein R1a is H; and R1b is C1-C6alkyl, Carbocyclyl or Het; or R1a and R1b together define a saturated cyclic amine with 3-6 ring atoms; R2a and R2b are independently H, halo, C1-C4alkyl, C1-C4haloalkyl or C1-C4alkoxy, or R2a and R2b together with the carbon atom to which they are attached form a C3-C6cycloalkyl; R3 is a branched C5-C10 alkyl chain, C2-C4haloalkyl or —CH2C3-C7 cycloalkyl; R4 is C1-C6alkyl, C1-C6haloalkyl, C1-C6alkylamino or C1-C6dialkylamino; for use in the prophylaxis or treatment of a disorder characterised by inappropriate expression or activation of cathepsin S.

Abstract: Compounds of Formula II wherein R1a is H; and R1b is C1-C6alkyl, Carbocyclyl or Het; or R1a and R1b together define a saturated cyclic amine with 3-6 ring atoms; R2a and R2b are independently H, halo, C1-C4alkyl, C1-C4haloalkyl or C1-C4alkoxy, or R2a and R2b together with the carbon atom to which they are attached form a C3-C6cycloalkyl; R3 is a branched C5-C10 alkyl chain, C2-C4haloalkyl or —CH2C3-C7 cycloalkyl; R4? is C1-C6alkyl, C1-C6haloalkyl or oxetany-3-yl. for use in the prophylaxis or treatment of a disorder characterized by inappropriate expression or activation of cathepsin S.

Abstract: Compounds of the formula I wherein R2a and R2b are independently H, halo, C1-C4alkyl, C1-C4haloalkyl or C1-C4alkoxy, or R2a and R2b together with the carbon atom to which they are attached form a C3-C6cycloalkyl; R3 is a C5-C10 alkyl, optionally substituted with 1-3 substituents independently selected from halo, C1-C4haloalkyl, C1-C4alkoxy, C1-C4haloalkoxy; or R3 is a C2-C4alkyl chain with at least 2 chloro or 3 fluoro substituents; or R3 is C3-C7cycloalkylmethyl, optionally substituted with 1-3 substituents independently selected from C1-C4alkyl, halo, C1-C4haloalkyl, C1-C4alkoxy, C1-C4haloalkoxy; R4 is C1-C6alkyl, C1-C6haloalkyl, C1-C6alkoxy, C1-C6haloalkoxy, C1-C6alkylamino, C1-C6dialkylamino or; R4 is Het or Carbocyclyl, either of which is optionally substituted with 1-3 substituents R4 is Het, carbocyclyl, C1-C6alkyl, C1-C6haloalkyl, C1-C6alkoxy or C1-C6haloalkoxy; n is 1, 2 or 3; for the use in the prophylaxis or treatment of a disorder characterised by inappropriate expression or activation of cath

Abstract: Compounds of Formula II wherein R1a is H; and R1b is C1-C6alkyl, Carbocyclyl or Het; or R1a and R1b together define a saturated cyclic amine with 3-6 ring atoms; R2a and R2b are independently H, halo, C1-C4alkyl, C1-C4haloalkyl or C1-C4alkoxy, or R2a and R2b together with the carbon atom to which they are attached form a C3-C6cycloalkyl; R3 is a branched C5-C10 alkyl chain, C2-C4haloalkyl or —CH2C3-C7 cycloalkyl; R4? is C1-C6alkyl, C1-C6haloalkyl or oxetany-3-yl. for use in the prophylaxis or treatment of a disorder characterised by inappropriate expression or activation of cathepsin S.

Abstract: Compounds of the formula I wherein R1a is H; and R1b is C1-C6alkyl, Carbocyclyl or Het; or R1a and R1b together define a saturated cyclic amine with 3-6 ring atoms; R2a and R2b are independently H, halo, C1-C4alkyl, C1-C4haloalkyl or C1-C4alkoxy, or R2a and R2b together with the carbon atom to which they are attached form a C3-C6cycloalkyl; R3 is a branched C5-C10 alkyl chain, C2-C4haloalkyl or —CH2C3-C7 cycloalkyl; R4 is C1-C6alkyl, C1-C6haloalkyl, C1-C6alkylamino or C1-C6dialkylamino; for use in the prophylaxis or treatment of a disorder characterised by inappropriate expression or activation of cathepsin S.