Synthesis, biological evaluation and study of in vitro pharmacokinetic properties of antiviral agents against dengue

BATTINI, LEANDRO; VIDELA, MARIELA; BOLLINI, MARIELA; FERNANDEZ, GABRIELA A.; AUCAR, MARÍA GABRIELA; CAVASOTTO, CLAUDIO N.; LEAL, EMILSE S.; ADLER, NATALIA S.; MONGE, MARIA EUGENIA

Ciudad Autónoma de Buenos Aires

Congreso; Drug Discovery for Neglected Diseases International Congress 2018; 2018

Facultad de Farmacia y Bioquímica - Universidad de Buenos Aires

Dengue disease is an infection caused by dengue virus (DENV), which is transmitted by mosquitoes of the genus Aedes. At present, no specific antiviral therapy or effective vaccine is available to control this disease. Therefore, new approaches are required to prevent replication, pathogenesis and viral transmission. The DENV particle comprises a lipid membrane and an envelope glycoprotein E, which interacts with specific receptors on the surface of the host cell, enabling its entry. The crystal structure of the E protein of DENV-2 revealed a hydrophobic pocket occupied by a detergent molecule n-octyl-β-D-glucoside (β-OG). This allows the development of small molecules that potentially bind to the β-OG pocket and inhibit the process of viral entry.1 Our approach to identify new candidates that likely bind to the β-OG pocket, involved de novo design strategies with the ligand-growing program Biochemical and Organic Model Builder (BOMB). Quinazoline and pyrimidine scaffolds were identified as the best candidates with high bomb score, acceptable solubility (logS > -5) and predicted key interactions with the protein. The most suitable candidates were synthesized and evaluated for antiviral antivity using a reporter DENV assay that allows discriminating virus entry and replication. The first series of synthesized compounds showed moderate inhibitory activities and some of the quinazolines were cytotoxic. So, a new class of pyrimidine analogues were developed using molecular modelling, isosteric replacements and solubility optimization approaches that resulted in a several compounds with EC50 values in the sub and low-micromolar range that acted at the entry stage.The identification and optimization of the properties of a compound in the early stage of the drug discovery process are of crucial importance. A successful drug-lead candidate must possess favourable characteristics, including potency and selectivity to the biological target, minimal toxicity, good stability and physicochemical profile, and desirable ADME properties. In this way, we evaluated the pharmacokinetic in vitro properties of the most active candidates. Until now, we have determined the solubility and drug stability in different media (pH 1.2, 6.8 and 7.4), plasma (mouse and human) and metabolic stability is in progress.In conclusion, we identified novel and potent inhibitors of DENV entry targeting protein E via de novo design approach. Several compounds exhibited EC50 values in the sub and low micromolar range. These compounds will be subject of a more detailed and elaborated virological study to gain insights into the precise mode of action. Compounds with high activity and good pharmacokinetic profile will be selected as candidates for in vivo evaluation. References1-Modis, Y.; Y.; Ogata, S.; Clements, D.; Harrison, S. C. Nature 2004, 427, 313?319.2-Leal, E. S.; Aucar, M. G.; Gebhard, L. G.; Iglesias, N. G.; Pascual, M. J.; Casal, J. J.; Gamarnik, A. V.; Cavasotto, C. N.; Bollini, M. Bioorg. Med. Chem. Lett. 2017, DOI: 10.1016/j.bmcl.2017.06.049.