Fused tricyclic aryl compounds useful for the treatment of viral diseases

1. A compound having the formula:

or a pharmaceutically acceptable salt thereof, wherein each dotted line represents an optional and additional bond, such that only one optional and additional bond can be attached to each of Y 1 and Y 2 , and wherein:

A is imidazole or benzimidazole, wherein said imidazole group or said benzimidazole group can be optionally and independently substituted on one or more ring nitrogen atoms with R 1 and on one or more ring carbon atoms with R 3 ;

D is imidazole or benzimidazole, wherein said imidazole group or said benzimidazole group can be optionally and independently substituted on one or more ring nitrogen atoms with R 2 and on one or more ring carbon atoms with R 4 ;

L 1 and L 2 are each independently selected from a bond, C 1 -C 4 alkylene, —NH—, —C(O)—, —NHC(O)— and —S(O) 2 —;

the group:

is selected from:

each occurrence of R 1 is independently —C 1 -C 6 alkyl, —C 1 -C 6 haloalkyl, -(3 to 7-membered cycloalkyl) or -(4 to 7-membered heterocycloalkyl);

each occurrence of R 2 is independently —C 1 -C 6 alkyl, —C 1 -C 6 haloalkyl, -(3 to 7-membered cycloalkyl) or -(4 to 7-membered heterocycloalkyl);

R 3 and R 4 are each independently selected from:

each occurrence of R 5 is independently:

each occurrence of R a is independently H, C 1 -C 6 alkyl, haloalkyl, cycloalkyl or aryl; and

each occurrence of R b is independently C 1 -C 6 alkyl,

such that the compound of formula (I) contains at least one R 3 group and at least one R 4 group.

2. The compound of claim 1 , wherein L 1 and L 2 are each a bond.

3. The compound of claim 2 , wherein R 3 and R 4 are each:

4. The compound of claim 2 , wherein each occurrence of R 5 is independently selected from:

5. The compound of claim 4 , wherein each occurrence of R 5 is:

6. The compound of claim 1 having the formula:

or a pharmaceutically acceptable salt thereof,

wherein:

R f is H or F;

R g is H or F;

A and D are the same and are selected from:

 such that the bond adjacent to both nitrogen atoms in A and D is joined to the pyrrolidine ring of formula (Ib);

T is selected from:

7. The compound of claim 1 having the formula:

or a pharmaceutically acceptable salt thereof,

wherein:

R f is H or F;

R g is H or F;

A and D are the same and are selected from:

 such that the bond adjacent to both nitrogen atoms in A and D is joined to the pyrrolidine ring of formula (Ic);

L 1 is a bond, C 2 -C 4 alkylene, —NH—, —C(O)—, —NHC(O)— or —S(O) 2 —;

L 2 is a bond, C 2 -C 4 alkylene, —NH—, —C(O)—, or —S(O) 2 —, such that at least one of L 1 and L 2 is other than a bond; and

T is selected from:

8. The compound having the structure:

or a pharmaceutically acceptable salt thereof.

9. A pharmaceutical composition comprising at least one compound of formula (I) of claim 1 or a pharmaceutically acceptable salt thereof, and at least one pharmaceutically acceptable carrier.

10. The composition of claim 9 , further comprising at least one additional antiviral agent, which is not a compound of formula (I), wherein the additional antiviral agent(s) is selected from: an HCV polymerase inhibitor; an interferon; a RNA replication inhibitor; an antisense agent; a therapeutic vaccine; a protease inhibitor; an antibody therapy (monoclonal or polyclonal) and ribavirin.

11. A method for treating HCV infection in a patient, the method comprising administering to the patient an effective amount of at least one compound of formula (I) of claim 1 or a pharmaceutically acceptable salt thereof.

12. The method of claim 11 , further comprising administering to the patient at least one additional antiviral agent, which is not a compound of formula (I), wherein the additional antiviral agent(s) is selected from: an HCV polymerase inhibitor; an interferon; a RNA replication inhibitor; an antisense agent; a therapeutic vaccine; a protease inhibitor; an antibody therapy (monoclonal or polyclonal) and ribavirin, and wherein the amounts administered are together effective to treat the HCV infection.