Substituted benzimidazole antiviral agents

A method for treating mammals infected with RSV comprising the administration of a therapeutically effective amount of a compound having the Formula II or Formula III, or a pharmaceutically acceptable salts thereof,

• wherein:
• R1, R2, R3, R4, R5, R6, R7 and R8 are independently H, alkyl, alkyl substituted with 1 to 6 halogen atoms, NO2, CN, halogen, COR′, COOR′, and CONHR′, R′ is H or alkyl, and said alkyl contains 1 to 6 carbon atoms;
• X is straight, branched or cyclic alkylene group optionally containing one unsaturation double or triple bond, wherein said groups has 2 to 12 carbon atoms;
• Y is selected from:
• (a) R9, —NR9R10, —+NR9R10R11, —NHCOR9, ═N—O—R9;
• —CONHR9, —COOR9, —CO—R9, —OR9, wherein R9, R10 and R11 are independently H, straight, branched or cyclic alkyl containing 1 to 7 carbon atoms;
• or R9 taken together with R10 forms a cyclic alkyl group having 3 to 7 carbon atoms;
• (b) —N3, —CN, halogen, —NO2, —NR″SO2R′″, —SR″, —SOR″, —SO2R″, —SO2NR″,
• wherein said R″ and R′″ are independently hydrogen, C1–C6 alkyl, phenyl, or phenyl substituted with from 1 to 6 halogen atoms or C1–C6 alkyl groups;
• (c) phenyl or heterocycle, selected from dioxolane, pyridine, pyrrole, thiophene, pyrrolidine or piperidine, and wherein said phenyl is optionally substituted with from 1 to 6 halogen atoms or C1–C6 alkyl groups;
• or X and Y taken together is selected from —CH2Ph, —CH2COPh, —CH2CHOHPh,
• wherein n is 1 or 2, R is C1–C4 alkyl and Ph is phenyl;
• and
• Z is —(CR12R13)n—, wherein n is 1–4, and R12 and R13 are independently H, straight, branched or cyclic C1–C6 alkyl.