Inhibitors of hepatitis C virus polymerase

A compound according to Formula I:

• or a pharmaceutically acceptable salt thereof,
• wherein:
• one of X and Y is —CH— and the other is —N—;
• R1A and R1B are each selected from the group consisting of independently hydrogen, —C1-4alkyl, —C1-4alkyl-C3-7cycloalkyl, —C0-3alkyl-C5-7heterocycloalkyl, —C1-4hydroxyalkyl, —C1-4haloalkyl, —C1-4alkyl-O—C1-4alkyl, —S(O)2C1-4alkyl, —S(O)2—RP, —S(O)2C5-7aryl-C0-3alkyl, —C1-4alkyl-S(O)2RL, —C2-4alkyl-NRMRN, —C1-4alkyl-RO, —C0-3alkyl-RP, —C0-3alkyl-C(O)C1-4alkyl, —C0-3alkyl-C(O)—C1-4hydroxyalkyl, —C0-3alkyl-C(O)—O—C0-4alkyl-RO, —C0-3alkyl-C(O)—C0-4alkyl-RP, —C(O)O—C1-4alkyl, —C0-3alkyl-C(O)O—C0-4alkyl-RO, —C0-3alkyl-C(O)O—C0-4alkyl-RP, —C0-4alkyl-C(O)OH and, —C0-3alkyl-C(O)—C0-4alkyl-NRMRN;
• wherein:
• RL is selected from the group consisting of —C1-4alkyl, —C3-5cycloalkyl and, —NRMRN;
• RM and RN are independently hydrogen or, —C1-4alkyl;
• or RM and RN together with the atoms to which they are attached can form a 4- to 6-membered ring;
• RO is a 6- to 10-membered aryl or a 5- to 10-membered heteroaryl, in each case monocyclic or bicyclic, and optionally substituted with (a) one to three moieties independently selected from —C1-4alkyl, halogen, —NRMRN, and —C1-4haloalkyl, or (b) a 6-membered aryl or 5-6 membered heteroaryl, optionally substituted with one to three moieties independently selected from —C1-4alkyl, halogen, and —NRMRN;
• and
• RP is a 5- to 6-membered cycloalkyl or heterocycloalkyl group, optionally substituted with a hydroxyl;
• provided that at least one of R1A and R1B is hydrogen;
• R2 is selected from the group consisting of —C5-6cycloalkyl, —C5-6cycloalkyl-C1-3alkyl optionally substituted with a halogen, —C5-6cycloalkenyl, —C5-6cycloalkenyl-C1-3alkyl optionally substituted with a halogen and —C1-4alkyl-C3-5cycloalkyl;
• R3 is —RA—RB or halo;
• wherein RA is ethynyl, or phenyl optionally substituted with one or two halogens, and
• wherein RB selected from the group consisting of is hydrogen, —C1-6alkyl, —C0-3alkyl-NRMRN, —NHC1-3alkyl-RQ, —N(RU)C(O)—RQ, —C(O)NURQ, carboxyl, —C2-6alkenyl, —C2-6alkynyl, —C0-3alkyl-C3-6cycloalkyl, —C1-4alkoxy, -methyl-(C1-4alkoxy)1-2, —C0-3alkyl-NRSRT, —C3-7cycloalkyl-C0-3alkyl-RQ, —C0-4alkyl-RQ, —C2-6alkynylRQ and, —C2-4alkenyl-RQ;
• wherein RQ is a 5 to 9-membered monocyclic heteroaryl or 5 to 9-membered bicyclic heteroaryl or 3 to 7-membered cycloalkyl or 3 to 7-membered heterocycloalkyl, and, optionally substituted with one or two —C1-3alkyl or —NRMRN;
• RS and RT are each independently hydrogen or —C1-4alkyl, or one of RS and RT is hydrogen and the other is —C(O)-5- to 9-membered aryl or heteroaryl;
• and
• RU is hydrogen or —C1-4alkyl;
• provided that, if RA is phenyl, then RB appears at the para or meta position relative to the thiophene moiety;
• and
• R4 is selected from the group consisting of hydrogen, —C1-4alkyl, —C1-4alkyl-OC(O)O—C1-4alkyl, —C1-4alkyl-OC(O)—C1-4alkyl, —C1-4alkyl-OC(O)O—C3-6cycloalkyl, 5-methyl-2-oxo-[1,3]dioxol-4-ylmethyl-, —C0-3alkyl-C5-6aryl and, —C1-4alkyl-NRURV;
• wherein RU and RV are independently hydrogen or —C1-4alkyl.