Efficient One-Pot Synthesis of Indolhydroxy Derivatives Catalyzed by SnCl2, DFT Calculations and Docking Study

In this work we used an efficient and simple synthesis for the preparation of new indolhydroxy derivatives that has been performed by the reduction reaction of 2-nitrocinnamic acid or 2-nitrophenyl pyruvic acid with anhydrous stannous chloride (SnCl2) as a metal catalyst in different alcoholic solvents. During this transformation there was the involvement of intramolecular elimination cyclization. In the case of the reduction of 2-nitrocinnamic acid we obtained hydroxyindole plus hydroxyquinoline, on the other hand, the reduction of 2-nitrophenyl pyruvic acid gives hydroxyindole only, the products were obtained in suitable yields. The structures of all the synthesized compounds were fully characterized by different spectroscopic techniques such as 1H NMR, 13C NMR. In addition, the obtained products have been tested in silico against anti-human immunodeficiency virus type 1 (HIV-1) and SARS-CoV-2 virus. The outcomes of this work are very promising to develop more efficient antiviral compounds, indicating that these products may be a probable drugs for the SARS-CoV-2.