PD-404182 is an inhibitor of bacterial 2-keto-3-deoxyctulosonic acid (KDO) 8-P synthase. It is a virucidal compound that compromises the structural integrity of both hepatitis C virus and human immunodeficiency virus, likely by interacting with a nonlipid structural element of these viruses. In vitro studies revealed that PD-404182 physically disrupts variously pseudotyped lentiviruses and exposes the viral genomic RNA in a time- and temperature-dependent manner. Also, PD-404182 might be a tightly bound, covalent, or an irreversible inhibitor of human dimethylarginine dimethylaminohydrolase 1.