Discovery and Optimization of 2,4-Diaminoquinazoline Derivatives as a New Class of Potent Dengue Virus Inhibitors

The results of a high-throughput screening assay using the DENV-2 replicon showed that the 2,4-diaminoquinazoline derivative 4a has a high dengue virus inhibitory activity (EC50 = 0.15 mu M). A series of 2,4-diaminoquinazoline derivatives based on 4a as a lead compound were synthesized and subjected to structure-antidengue activity relationship studies. Among the series of 2,4-diaminoquinazoline derivative probed, 4o was observed to display both the highest antiviral potency (EC50 = 2.8 nM, SI > 1000) and an excellent pharmacokinetic profile.