Pyrimidone derivatives as selective cytotoxic agents against hiv infected cells

A compound of Formula I:

• or a pharmaceutically acceptable salt thereof, wherein:
• Ring A is selected from:
• R1a is halo, —C1-3alkyl unsubstituted or substituted with 1 to 7 of F;
• —OC1-3alkyl unsubstituted or substituted with 1 to 7 of F;
• or —NH2, —NH—C1-3alkyl, —N(C1-3alkyl)2, or —C3-6cycloalkyl;
• R2a is —H, halo, —C1-3alkyl, —CF3, —CHF2, —CH2F, —OC1-3 alkyl, —NH2, —NH—C1-3alkyl, —N(C1-3alkyl)2, or —C3-6cycloalkyl or —OC1-3alkyl unsubstituted or substituted with 1 to 3 of F;
• R3a is —H or halo;
• provided that R2a and R3a are not both —H;
• R1b is halo, —C1-3alkyl, —CF3, —CHF2—CH2F, —NH2, —NH—C1-3alkyl, —N(C1-3alkyl)2, —C3-6cycloalkyl, or —OC1-3alkyl unsubstituted or substituted with 1 to 3 of F;
• R3b is halo, —C1-3alkyl, —CF3, —CHF2—CH2F, —NH2, —NH—C1-3alkyl, —N(C1-3alkyl)2, —C3-6cycloalkyl, or —OC1-3 alkyl unsubstituted or substituted with 1 to 3 of F;
• R1c is —H, halo, —C1-3alkyl, —CF3, —CHF2, —CH2F, —NH2, —NH—C1-3alkyl, —N(C1-3alkyl)2, —C3-6cycloalkyl, or —OC1-3alkyl unsubstituted or substituted with 1 to 3 of F;
• R2c is —H, bromo, —C1-3alkyl, —CF3, —CHF2, —CH2F, —NH2, —NH—C1-3alkyl, —N(C1-3 alkyl)2, —C3-6cycloalkyl, or —OC1-3alkyl unsubstituted or substituted with 1 to 3 of F;
• provided that one of R1c or R2c is —H and the other is not —H;
• R4 is halo or —C1-6alkyl substituted with 1 to 8 of —F;
• R5 is —H, —NH2, —NH—C1-3alkyl, —N(C1-3alkyl)2, —C3-6cycloalkyl, or —C1-3alkyl unsubstituted or substituted with 1 to 7 of —F;
• R6 is —H, —C1-4alkyl, —C2-4 alkenyl, —NH2, —NH—C1-3alkyl, —N(C1-3alkyl)2, C3-6cycloalkyl, -pyrazolyl unsubstituted or substituted with C1-3alkyl, or —C1-4alkyl substituted with R7;
• and
• R7 is —OH, —OC1-3alkyl, —C(O)OC1-3alkyl or —CH2O-pyrimidinyl.