Discovery of diphenylmethane analogs as anti-bovine diarrhea viral agents.

Based on antiviral screening of our diphenylmethane derivatives prepared as steroid substitutes, we identified a 1,1-diphenylcyclobutane analog (9) and two diethyldiphenylsilane analogs (12 and 13) as superior lead compounds with potent anti-bovine viral diarrhea virus (BVDV) activity, having 50% effective concentration (EC(50): based on reduction of BVDV replication-induced cell destruction) and 50% cytotoxic concentration (CC(50): based on reduction of viable cell number) values of 6.2-8.4 microM and >100 microM, respectively, in Madin-Darby bovine kidney (MDBK) cells infected with BVDV.