2-(Ethylthio)-1-methyl-6-{2-[1-(6-methylpyridazin-3-yl)piperidin-4-yl]ethoxy}-1H-benzimidazole and 2-(Ethylthio)-1-methyl-5-{2-[1-(6-methylpyridazin-3-yl)piperidin-4-yl]ethoxy}-1H-benzimidazole AIDS-167368 AIDS167368