Synthesis, biological evaluation and molecular modeling of a novel series of fused 1,2,3-triazoles as potential anti-coronavirus agents

Abstract

Synthesis and biological evaluation of a novel library of fused 1,2,3-triazole derivatives are described. The in-house developed multicomponent reaction based on commercially available starting materials was applied and broad biological screening against various viruses was performed, showing promising antiviral properties for compounds 14d, 14n, 14q, 18f and 18i against human coronavirus 229E. Further in silico studies identified the key molecular interactions between those compounds and the 3-chymotrypsin-like protease, which is essential to the intracellular replication of the virus, supporting the hypothesis that the protease is the target molecule of the potential antiviral derivatives.

Keywords: 1,2,3-triazole; 3CL protease; Biological evaluation; Coronavirus; Respiratory syndrome.

Graphical abstract

Fig. 1

Representative A) peptidic and B) small molecule SARS-CoV 3CL^pro inhibitors., , , , ,

Scheme 1

Synthetic pathway towards derivatives 14a–r. Reagents and conditions:(a) AcOH, CuCl, 24 h, 110 °C, 55%, (b) NaH, Toluene, EtOH, 6 h, 100 °C, 90%, (c) BnBr, K₂CO₃, THF, 6 h, 70 °C, 65%,(d) Toluene, 18 h, 100 °C.

Scheme 2

Reagents and conditions: (a) Pd(OAc)₂, XPhos, NaO-t-Bu, Toluene/t-BuOH (5:1), 18 h, 120 °C, 65%, (b) aq. HCl (5 N), 3 h, 100 °C, 45%,(c) Toluene, 18 h, 100 °C.