Synthesis of new compounds with promising antiviral properties against group A and B Human Rhinoviruses

The human common cold, which is a benign disease caused by the Rhinoviruses, generally receives palliative symptomatic treatments, since no specific therapy against any of these viruses currently exists. In this work, some original synthetic compounds were produced and tested, in order to find non-toxic substances with an improved protection index (PI) for infected cells, as compared to reference drugs such as Pirodavir. We designed a series of novel molecules with a double oxygen in the central hydrocarbon chain and some modifications of the lateral methylisoxazole and propoxybenzoate moieties of lead compound 6602 (ethyl 4-{3-[2-(3-methyl-1,2-isoxazol-5-yl)ethoxy]propoxy}benzoate). It was found that most of these substances were actually less toxic than Pirodavir; in addition, the new molecule indicated as 8c was more than 30 times less toxic than Pirodavir, about twice as active on the group A strain of Rhinovirus HRV14, and even four times more effective on the group B strain HRV39, as compared to Pirodavir’s PI.