Novel 3-chloro-6-nitro-1-indazole derivatives as promising antileishmanial candidates: synthesis, biological activity, and molecular modelling studies.

An efficient pathway was disclosed for the synthesis of 3-chloro-6-nitro-1-indazole derivatives by 1,3-dipolar cycloaddition on dipolarophile compounds and . Faced the problem of separation of two regioisomers, a click chemistry method has allowed us to obtain regioisomers of triazole-1,4 with good yields from 82 to 90% were employed. Also, the antileishmanial biological potency of the compounds was achieved using an MTT assay that reported compound as a promising growth inhibitor of . Molecular docking demonstrated highly stable binding with the Leishmania trypanothione reductase enzyme and produced a network of hydrophobic and hydrophilic interactions. Molecular dynamics simulations were performed for TryR- complex to understand its structural and intermolecular affinity stability in a biological environment. The studied complex remained in good equilibrium with a structure deviation of ∼1-3 Å. MM/GBSA binding free energies illustrated the high stability of TryR- complex. The studied compounds are promising leads for structural optimisation to enhance the antileishmanial activity.