Metallo-antiviral aspirants: Answer to the upcoming virus outbreak

Abstract

In light of the current SARS-CoV-2 outbreak, about one million research papers (articles, reviews, communications, etc.) were published in the last one and a half years. It was also noticed that in the past few years; infectious diseases, mainly those of viral origin, burdened the public health systems worldwide. The current wave of the Covid-19 pandemic has unmasked critical demand for compounds that can be swiftly mobilized for the treatment of re-emerging or emerging viral infections. With the potential chemical and structural characteristics of organic motifs, the coordination compounds might be a promising and flexible option for drug development. Their therapeutic consequence may be tuned by varying metal nature and its oxidation number, ligands characteristics, and stereochemistry of the species formed. The emerging successes of cisplatin in cancer chemotherapy inspire researchers to make new efforts for studying metallodrugs as antivirals. Metal-based compounds have immense therapeutic potential in terms of structural diversity and possible mechanisms of action; therefore, they might offer an excellent opportunity to achieve new antivirals. This review is an attempt to summarize the current status of antiviral therapies against SARS-CoV-2 from the available literature sources, discuss the specific challenges and solutions in the development of metal-based antivirals, and also talk about the possibility to accelerate discovery efforts in this direction.

Keywords: Covid-19; Inorganic pharmacology; Metal-based compounds; Metallodrug; SARS–CoV–2; Therapeutic applications.

Graphical abstract

Fig. 1

Life process of the single-stranded RNA of the SARS-CoV-2.

Fig. 2

Structure of bis-violurate manganese(II) and copper(II) complexes.

Fig. 3

Structure of zinc pyrithiones complexes. (Where, X ​= ​–H in Zn–1; 3-CH₃ in Zn–2; 4-CH₃ in Zn–3; 5-CH₃ in Zn–4; and 6-CH₃ in Zn–5.

Fig. 4

Structure of Molybdenum carbonyl complexes with benzimidazole derivatives. (Where, X ​= ​–H in Mo–1; -Cl in Mo–2; and –OCH₃ in Mo–3.

Fig. 5

Structure of the half sandwich ruthenium compounds. (Where, X ​= ​–H in Ru-1; 4-Cl in Ru-2; 4-NO₂ in Ru-3; 4-COOH in Ru-4; and 3-methoxy-4-hrdroxy in Ru-5.

Fig. 6

Organorhodium compounds with pentamethylcyclopentadienide (Cp∗) ligand.

Fig. 7

Structure of palladium complexes prepared by Serbian research. (Where, X ​= ​–H in Pd–1; 3-Cl in Pd–2; and 4-Cl in Pd–3.

Fig. 8

Rhenium carbonyl compounds with 2,2'-bipyridine scaffolds. (Where, X ​= ​–CN in Re-2, Re-7, Re-15, Re-19, Re-23, Re-28, Re-36, Re-40; –OH in Re-3, Re-10, Re-16, Re-20, Re-24, Re-31, Re-37, Re-41; –COOH in Re-4, Re-12, Re-17, Re-25, Re-33, Re-38, –NH₂ in Re-5, Re-13, Re-18, Re-21, Re-26, Re-34, Re-39, Re-42; –CH₃ in Re-6, Re-27; -Cl in Re-8, Re-29; -Br in Re-9, Re-30; –OCH₃ in Re-11, Re-32; –NO₂ in Re-14 and Re-35).

Fig. 9

The Gold compounds examined against coronavirus molecular targets.

Fig. 10

Structure of Gallium maltolate (GaM).

Fig. 11

Bismuth porphyrin complexes. (Where, X ​= ​-Ar in Bi–1; and 3,4,5-trimethoxybenzene in Bi–2.