Discovery and structural optimization of a new series of N-acyl-2-aminobenzothiazole as inhibitors of Zika virus.

Zika virus infection is associated to severe diseases such as congenital microcephaly and Zika fever causing serious harm to humans and special concern to health systems in low-income countries. Currently, there are no approved drugs against the virus, and the development of anti-Zika virus drugs is thus urgent. The present investigation describes the discovery and hit expansion of a N-acyl-2-aminobenzothiazole series of compounds against Zika virus replication. A structure-activity relationship study was obtained with the synthesis and evaluation of anti-Zika virus activity and cytotoxicity on Vero cells of nineteen derivatives. The three optimized compounds were 2.2-fold more potent than the initial hit and 20.9, 7.7 and 6.4-fold more selective. Subsequent phenotypic and biochemical assays were performed to evidence whether non-structural proteins, such as the complex NS2B-NS3pro, are related to the mechanism of action of the most active compounds.