West Nile Virus (WNV) is a mosquito-borne pathogen that causes febrile illness and, occasionally, encephalitis when transmitted to humans. Infection can cause significant health problems such as West Nile fever and neuroinvasive disease. The goal of the assay was to identify and develop chemical probes that inhibit in vitro replication of WNV. An unbiased phenotypic whole virus cell-based assay was utilized to select chemical probes that inhibit WNV propagation without adversely affecting the host cell. The two probe candidates described in this report, ML143 (CID-2557019) and ML142 (CID-928277), provide two small molecules that demonstrate modest yet useful potency against the West Nile Virus, but with a robust margin of selectivity against cell cytotoxicity, providing potentially useful evaluation tools for small animal toxicity and efficacy studies.