Novel oxazolidinone zinc(II) complexes as antibacterial and anti-SARS-CoV-2 agents: synthesis, characterization, DFT calculations, ADMET, in silico molecular docking and biological activities

A series of Zn(II) complexes with oxazolidinone derivatives has been synthesized and characterized using spectroscopic techniques: IR, H-1 NMR, UV-Vis spectroscopy, and TGA/DTG thermal investigation. Theoretical computations were carried out using B3LYP/6-31G(d) and B3LYP/LanL2DZ to analyze the vibrational properties, NBO charges, global chemical reactivity indices and to illustrate the FOMs. TD-DFT calculations using WB97XD functional were realized with 6-31 G(d) and LAN2DZ basis set on oxazolidinone ligands and their zinc complexes. The pharmacokinetic properties and toxicity of the investigated compounds were predicted using in silico ADMET studies. Moreover, the S. aureus, E. coli, S. pneumoniae, ribosome 50S subunit, SARS-Cov-2 spike protein and ACE2 human receptor were selected for molecular docking study. The docking study shows that HL4 and ZnL4 bind better to the spike protein and hACE2 receptor. The redox properties were also studied for ligands and their corresponding complexes using cyclic voltammetry. Finally, antioxidant activity studies using DPPH radical scavenging showed efficiency for HL2 and [Zn(L-2)(2)] with low values of IC50 compared to ascorbic acid. The antimicrobial activity against B. subtilis (ATCC 9372), E. faecalis (ATCC 29212), S. aureus (ATCC 6538), E. coli (ATCC 4157), bacteria strains, C. albicans (ATCC 24433) and A. niger fungi strains were evaluated.

Structural and Computational Studies of Cobalt(II) and Copper(II) Complexes with Aromatic Heterocyclic Ligand

Two coordination complexes, a cobalt(II) complex tris(1,10-phenanthroline)-cobalt perchlorate hydrate, [Co(phen)3]·(ClO4)2·H2O(1), and a copper(II) complex tris(1,10-phenanthroline)-copper perchlorate 4-bromo-2-{[(naphthalene-1-yl)imino]methyl}phenol hydrate, [Cu(phen)3]·(ClO4)2·HL·[O] (2), [where, phen = 1,10-phenathroline as aromatic heterocyclic ligand, HL = 4-bromo-2-((Z)-(naphthalene-4-ylimino) methyl) phenol] have been synthesized and structurally characterized. Single crystal X-ray analysis of both complexes has revealed the presence of a distorted octahedral geometry around cobalt(II) and copper(II) ions. density functional theory (DFT)-based quantum chemical calculations were performed on the cationic complex [Co(phen)3]2+ and copper(II) complex [Cu(phen)3]2+ to get the structure property relationship. Hirshfeld surface and 2-D fingerprint plots have been explored in the crystal structure of both the metal complexes. To find potential SARS-CoV-2 drug candidates, both the complexes were subjected to molecular docking calculations with SARS-CoV-2 virus (PDB ID: 7BQY and 7C2Q). We have found stable docked structures where docked metal chelates could readily bound to the SARS-CoV-2 Mpro. The molecular docking calculations of the complex (1) into the 7C2Q-main protease of SARS-CoV-2 virus revealed the binding energy of −9.4 kcal/mol with a good inhibition constant of 1.834 µM, while complex (2) exhibited the binding energy of −9.0 kcal/mol, and the inhibition constant of 1.365 µM at the inhibition binding site of receptor protein. Overall, our in silico studies explored the potential role of cobalt(II) complex (1), and copper(II) complex (2) complex as the viable and alternative therapeutic solution for SARS-CoV-2.

New Nickel (II), Copper (II) and Cobalt (II) Complexes Based Salicyaldehyde Schiff Base: Synthesis, Characterisation, and Antiviral Activity

The three metal complexes were synthesized from schiff base which were formed by condensation of salicyaldehyde and 4-chlorophenylethanaamine. The spectral characterisation is done by UV–Vis., 1H NMR and LCMS. The spectroscopic results evidenced the interaction of the ligands and their Nickel (II), Cobalt (II) and Copper (II) complexes. Antivirals are medicines that help stop a virus infecting healthy cells or multiplying in body. Metal–organic frameworks (MOFs) combined with bio macromolecules, viruses and cells have emerged as novel bio composites for application to drug delivery, bio sensing, bio specimen preservation, and cell and virus manipulation These synthesized compounds have been screened for antiviral activity (covid virus, hepatitis B virus) strains by using dics diffusion method. Antiviral medicines target the virus (SARS-CoV-2) that causes COVID-19 to prevent it infecting healthy cells in your body and multiplying. The antiviral activity of synthesized Schiff bases and metal complexes exhibited moderate degrees of inhibitory effects. Among these, complex 3 show better activity toward covid virus and hepatitis virus. It was found that complex 3 displayed higher antiviral activity than Schiff base ligand (L-1) compared with the Acyclovir used as standard.

A Comprehensive Survey on the Expediated Anti-COVID-19 Options Enabled by Metal Complexes-Tasks and Trials.

Contemporary pharmacology dating back to the late 19th/early 20th centuries has benefitted largely from the incorporation of metal complexes. Various biological attributes have been successfully realized using metal/metal complex-based drugs. Among anticancer, antimicrobial, and antiviral applications, anticancer applications have extracted the maximum benefit from the metal complex, Cisplatin. The following review has compiled the various antiviral benefits harnessed through inputs from metal complexes. As a result of exploiting the pharmacological aspects of metal complexes, the anti-COVID-19 deliverables have been summarized. The challenges ahead, the gaps in this research area, the need to improvise incorporating nanoaspects in metal complexes, and the need to test metal complex-based drugs in clinical trials have been discussed and deliberated. The pandemic shook the entire world and claimed quite a percentage of the global population. Metal complex-based drugs are already established for their antiviral property with respect to enveloped viruses and extrapolating them for COVID-19 can be an effective way to manipulate drug resistance and mutant issues that the current anti-COVID-19 drugs are facing.

Synthesis, characterization, molecular docking and network pharmacology of bioactive metallic sulfonamide-isatin ligands against promising drug targets

• Synthesis of new Sulfonamide-isatin based scaffolds to incorporate first row metals. • Molecular docking to find a best docking pocket for COVID-19 protein. • Online network pharmacology to find a best target for Alzheimer and carbonic anhydrase-II related gene targets. • Characterization with most promising analytical techniques and DFT based studies. • In vitro enzyme inhibition and antimicrobial profiling of new compounds. A series of sulfonamide and isatin based Schiff bases, (S1) and (S2), and their metal (Co2+, Ni2+, Cu2+ and Zn2+) complexes (1)-(8) were synthesized and characterized by spectroscopic (UV, IR, MS, 1H and 13C-NMR), elemental, magnetic and physical techniques. The non-electrolytic character of Co2+, Ni2+, and Zn2+ compounds and electrolytic nature of Cu2+ was established by their conductance studies. The energies of Frontier Molecular Orbitals (FMOs) were also used to explore various global and quantum chemical qualities. To find the activity and molecular targets in curing Alzheimer's Disease (AD) and Carbonic Anhydrase II (CA-II) inhibition, Network Pharmacology modeling was used. The prospective targets were predicted using the Swiss Target PredictionR online facility. The Gene CardsR database has been used to find genes linked to AD and CA-II. We also conducted Gene OntologyR (GO) analysis on the intersecting genes targets on active targets of synthesized compounds by DAVID (Database for Annotation, Visualization and Integrated Discovery) Bioinformatics Services using the CytoscapeR program. The in vitro enzyme inhibition assays were done against protease, amylase, acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) while their antimicrobial studies were performed against pathogenic bacterial and fungal species. The antioxidant values, evaluated as 2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing assay power (FRAP) (%) ranged between 51.0±0.11-68.1±0.11% with IC 50 ranging 146.84-196.08 µL/mol. [Display omitted] [ FROM AUTHOR]

Metal complexes of Tridentate Schiff base: Synthesis, Characterization, Biological Activity and Molecular Docking Studies with COVID-19 Protein Receptor.

Mononuclear chelates of Cr(III), Mn(II), Fe(III), Ni(II), Cu(II), Zn(II) and Cd(II) resulted from new tridentate Schiff base ligand, 4-((1-(5-acetyl-2,4-dihydroxyphenyl)ethylidene)amino)-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one, were synthesized. Metal to ligand ratio was found to be1 : 1, which was revealed via elemental analysis and characterized via various spectroscopic tools. IR has point out that the coordination of the ligand towards the metal ions was carried out via NOO donor atoms. UV-Vis, 1H NMR spectral data, molar conductivity measurements, BET surface area, melting points and theoretically through density function theory were used such as characterizing techniques in supporting further interpretation of the complexes structures. The complexes were octahedral except Cu(II) and Ni(II) complexes were tetrahedral as suggested from the magnetic moment measurement. The complexes were found to have surface area, pore volume and particle radius of 23-176 m2 g-1, 0.02-0.33 cc/g and 8.71-4.32 nm, respectively, as pointed out from BET measurement. Schiff base ligand and metal complexes were tested in vitro to estimate their antimicrobial activity opposed to Gram-negative and Gram-positive bacterial and fungal organisms. MOE 2008 was used headed for screen potential drugs with molecular docking by the protein sites of new coronavirus and the study was constructed to molecular docking without validation through MD simulations.

New Schiff base copper(II) and nickel(II) complexes for biomedical applications with reference to SARS-CoV-2 and HIV virus

A series of nickel(II) and copper(II) complexes viz. [Ni(L1)2](1), [Cu(L1)2](2), [Ni(L2)2](3) and [Cu(L2)2](4) (where L1H=(E)-N-phenyl-2-(thiophen-2-ylmethylene)hydrazine-1-carboxamide, L2H=(E)-2-((3-methylthiophen-2-yl) methylene)N-phenylhydrazine-1-carbothioamide), have been synthesized and designed as potential inhibitors against SARS-CoV-2 and HIV-1 virus. The quantum computational calculations are used for structure-property relationship. A detailed structural and non-covalent supramolecular interaction in the ligand (L1H) is investigated by single crystal structure analysis and computational approaches. Hirshfeld surface analysis is done in the crystal structure of the ligand (L1H), while 3D topology of the crystal packing is visualized through an energy framework. To find potential inhibitors of the SARS-CoV-2 and HIV-1 virus, molecular docking of the ligands and their corresponding metal complexes with SARS-CoV-2 and HIV-1 virus is performed. The X-ray crystallographic structure of the main protease of the SARS-CoV-2 (PDB ID: 7VNB) and HIV-1 virus (PDB ID: 1REV) is retrieved from the protein data bank and used as receptor proteins. The molecular docking results has shown that Schiff bases and their complexes with SARS-CoV-2 and HIV-1 virus exhibited good binding affinity at binding site of receptor protein. It is also observed that the binding affinities of the Schiff bases and metal complexes towards SARS-CoV-2 are comparatively higher than the HIV virus. This study may offer the new antivirus drug candidates against SARS-CoV-2 and HIV-1 virus. © 2022 Indian Journal of Chemistry (IJC). All right reserved.

New nickel(ii) Schiff base complexes as potential tools against SARS-CoV-2 Omicron target proteins: an in silico approach

Herein, we report the in silico design and synthesis of two new nickel(ii) coordination complexes, viz., [Ni(L-1)][(PPh3)]DMF (1) and [Ni(L-2)] (2), based on Schiff bases derived from the 2-hydroxy-1-naphthaldehyde moiety (where, (LH2)-H-1 = (E)-3-(((5-chloro-2-hydroxyphenyl)imino)methyl)naphthalene-2-ol), ((LH2)-H-2 = 2,2 & PRIME;-((1E,1 & PRIME;E)-(ethane-1,2-diylbis(azaneylylidene))bis(methaneylylidene))bis(naphthalen-2-ol)), PPh3 = (triphenylphosphine). The synthesized ligands (LH2)-H-1 and (LH2)-H-2 were coordinated to Ni(ii) ions through the tridentate-ONO and tetradentate-N2O2 donor atoms, respectively. The newly synthesized complexes were fully characterized using X-ray crystallography analysis. The synthesized complexes (1) and (2) crystallized in the triclinic and monoclinic crystal system with the P1 and P21/c space group, respectively, and exhibited a square planar geometry around the Ni(ii) ions. Computational approaches were employed to determine the structure-property relationship of the complexes. Hirshfeld surface analysis was also performed to investigate intermolecular interactions in the crystal systems. The strength of the interaction and 3D topology of crystal packing were visualized through an energy framework. To gain insights into the potential application of Ni(ii) complexes as effective SARS-CoV-2 Omicron inhibitors, we performed the following docks (a) Ni(ii) complexes with S protein from original SARS-CoV-2 (PDB ID: 7CWO), (b) Ni(ii) complexes with selected Omicron targets (PDB ID: 7QTK and 7WK8) and (c) controls ivermectin and levosalbutamol with the original SARS-CoV-2 spike protein and the Omicron S proteins. The synthesized Ni(ii) complexes (1) and (2) showed good docking results with the S protein of SARS-CoV-2, where the binding energies (& UDelta;G) and respective K-i (inhibition constants) correlation values are -7.38 (3.87 mu M) and -8.82 (341.77 nM), respectively. The molecular docking results revealed that the synthesized complexes (1) and (2) with the SARS-CoV-2 Omicron target protein (PDB ID: 7QTK) resulted the binding energy (& UDelta;G) of -7.46 kcal mol(-1) with an inhibition constant (K-i) of 3.39 mu M and binding energy (& UDelta;G) of -7.56 kcal mol(-1) with an inhibition constant (K-i) of 2.89 mu M, respectively. Similarly, the synthesized Ni(ii) complexes (1) and (2) with the SARS-CoV-2 Omicron target protein (PDB ID: 7WK8) exhibited the binding energy (& UDelta;G) and inhibition constant (K-i) of -7.03 kcal mol(-1) and 7.08 mu M and -7.89 kcal mol(-1) and 1.64 mu M, respectively. It was predicted that ivermectin shows a larger binding energy (& UDelta;G) for S proteins compared to levosalbutamol after molecular docking. Further, in silico ADMET to predict the drug-likeness behaviour and pharmacokinetic response of the synthesized complexes was also explored. Overall, the present study suggests that nickel(ii) complexes can be considered as potential therapeutic drugs against the Omicron target protein of SARS-CoV-2.

Synthesis, structural investigations, XRD, DFT, anticancer and molecular docking study of a series of thiazole based Schiff base metal complexes

A novel Schiff base (SB) ligand, abbreviated as HDMPM, resulted from the condensation of 2-amino-4 -phenyl-5-methyl thiazole and 4-(diethylamino)salicyaldehyde, and its metal complexes with [Co(II), Cu(II), Ni(II), and Zn(II)] ions in high yield were formed. The physico-chemical techniques such as elemental analysis, molar conductance, IR, 1 H and 13 C NMR, mass spectroscopy, and electronic absorption studies were utilized to characterize the synthesized compounds. The studied compounds were examined for their possible anticancer activity against a number of human cancerous cell lines, including A549 lung carcinoma, HepG2 liver cancer, HCT116 colorectal cancer, and MCF-7 breast cancer cell lines, with dox-orubicin serving as the standard. The study revealed that Zn(II) complex showed significant activity to inhibit growth of HepG2, MCF7, A549, and HCT116 cell lines by a factor of 88, 70, 75, and 70, respec-tively, when compared to untreated. In addition, the reported compounds were optimized by employing Gaussian16 program package with B3LYP functional incorporating dispersion with two different basis sets (LanL2DZ and 6-31G(d,p)). Moreover, Autodock Vina software was used to assess the biological effective-ness of the studied compounds against SARS-CoV-2 Omicron variant (PDB ID: 7T9K).(c) 2022 Elsevier B.V. All rights reserved.

Co(II), Ni(II), Cu(II) and Zn(II) complexes of Schiff base ligands: synthesis, characterization, DFT, in vitro antimicrobial activity and molecular docking studies

Three Schiff base ligands [H2L1-H2L3] containing nitrogen/oxygen donor atoms and their Co(II), Ni(II), Cu(II) and Zn(II) complexes were synthesized by stirring metal acetates with Schiff base ligands obtained from condensation reaction of 2-amino-6-chloro-4-nitrophenol with 5-chloro salicylaldehyde/3,5-dibromo salicylaldehyde/3-methoxy-5-nitro salicylaldehyde. The structural traits of the synthesized compounds were done by using elemental analysis, spectroscopic techniques (UV-Vis, H-1 and C-13 NMR, FT-IR), mass spectrometry and some physical studies (XRD, TGA). According to spectral data, ligands behave as a tridentate (ONO) and formed complexes with octahedral geometry. The thermogravimetric analysis revealed that metal complexes decay in multi-steps leaving metal oxide as an end product. Powder XRD study suggested crystalline nature of the compounds. The energy gap (HOMO-LUMO) and molecular electrostatic potential calculation were computed by using DFT/B3LYP/6-31G** basis set. Derived ligands and complexes were explored for in vitro antimicrobial potential toward two gram-positive bacteria, two gram-negative bacteria, i.e., S. aureus, B. subtilis, P. aeruginosa, E. coli, and two fungal strains, i.e., A. niger, C. albicans, through serial dilution method taking ciprofloxacin and fluconazole as standard. The investigated results showed that complexes are more potent than free Schiff base ligands. The Cu(L-2)(H2O)(3) (0.0115 mu mol/mL) and Zn(L-2)(H2O)(3) (0.0115 mu mol/mL) complexes were found to be more active among all the investigated compounds. Additionally, molecular docking studies were also performed for some compounds in the active site of DNA Gyrase enzyme (PDB code: 1AJ6), suggesting good hydrophobic interactions of compounds with the enzyme.

Brief History, Pathophysiology, Transmission of SARS-CoV-2 Virus, and Recent Advances on Transition Metal Complexes and Nanocomposites as the Potent Antiviral Agents from COVID-19 Perspectives

The outbreak of SARS-CoV-2 has resulted in an unprecedented and greatest global health crisis in the present century affecting more than 220 countries with 3.7 million deaths and 173.5 million individual infections till now. This pandemic has had an enormous impact on global healthcare, economy, and society, which has prompted extensive research on exploring the biology of SARS-CoV-2 and the discovery of new drugs for COVID-19. The lack of effective antiviral drugs for COVID-19 has initiated the effort to repurpose selected FDA-approved antiviral drugs for the treatment of COVID-19 along with plasma therapy. Vaccination has proven to be the effective prevention strategy against the SARS-CoV-2 virus, although mutations in the SARS-CoV-2 virus have become the major concern due to the decreasing effectiveness of the vaccines Therefore, an effective cure for COVID-19 is still an elusive goal. Transition metal complexes by a broad spectrum of formal charge and oxidation states, wide range of coordination number and geometry, tunable kinetic, thermodynamic, and redox properties, diverse reaction pathways have emerged as the alternative and viable tools in the medicinal domain from therapeutics to diagnostics. Several transition metal complexes proved their efficacy against various types of viruses and recent advances on the potent transition metal complexes or nanoconjugates are reviewed in this chapter. The present chapter also aims to discuss the perspectives on the potential utility of transition metal complexes or the nanoconjugates against SARS-CoV-2. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

Syntheses and structural characterization of divalent metal complexes (Co, Ni, Pd and Zn) of sterically hindered thiourea ligand and a theoretical insight of their interaction with SARS-CoV-2 enzyme.

Reacting two equivalents of sterically hindered 1,3-bis(2,6-diethylphenyl)thiourea ligand (L) with CoCl2, NiBr2, PdX2 (X = Cl; Br) and ZnI2 in acetonitrile afforded the corresponding bulky thiourea ligand stabilized four coordinated monomeric [L2CoCl2] (1), [L2NiBr2] (2), [L2PdX2] (3a: X = Cl; 3b: X = Br) and [L2ZnI2] (4.2CH3CN) complexes. Compound 1, 2 and 4.2CH3CN are tetrahedral whereas Pd complexes (3a and 3b) are square planar. In solution, palladium complexes are dominated by cis-isomers. Structural characterization shows inter- and intramolecular hydrogen bonding. Hirshfeld surface and fingerprint plots indicated significant intermolecular interactions in the crystal network. Molecular docking analysis revealed relatively higher SARS-CoV-2 enzyme interacting abilities of the synthesized complexes compared to the free ligand. All compounds have been characterized by elemental analyses, NMR spectroscopy and single-crystal X-ray diffraction.

Synthesis, Characterization, Biological Activity, Molecular Docking and Thermal Analysis of Binuclear Complexes

Because of their potential medical applications as antimicrobial medicines, metal-ligand complexes have sparked a lot of attention. Synthesis and characterization of various metal-diamine complexes were the goals of the research detailed in this paper. As a result, synthesis of new binuclear ligand;N,N'-bis(3-carboxysalcylidene)-4-chloro-1,2-phenylenediamine (H(4)fsacph) which is derivative from the condensation of 3-formyl-2-hydroxybenzoic acid and 4-chlorobenzene-1,2-diamine has been performed. The new synthesized ligand has formed a mononuclear complex with Cu(II). The mononuclear Cu(II) complex was used to form binary nuclear complexes with some metal ions, like Cr(III), Mn(II), Fe(III), Ru(III), Pd(II) and La(III) ions. Elemental analysis, IR, UV-Visible, and thermal analyzes have been used to characterize the complexes. The interaction of a ligand with the receptors of Candida albicans and SARS-CoV-2 was predicted using molecular docking. Toward bacteria and fungi showing predominant activity against all fungi verified antibacterial activity of the synthesized complexes, while they have almost no activity against all bacteria. All compounds have shown antibacterial and antifungal activities, but the metal complexes showed better activities as compared to the original ligands, especially all zinc(II) complexes. The above results suggest that both ligands and their metal complexes have the potential to be explored as active pharmaceutical agents.

Synthesis and characterization of violurate-based Mn(II) and Cu(II) complexes nano-crystallites as DNA-binders and therapeutics agents against SARS-CoV-2 virus

Synthesis and structural characterization of nano crystallites of bis-violurate-based manganese(II) and copper(II) chelates is the subject of the present study. Analytical data and mass spectra as well as thermal analysis determined the molecular formulas of the present metal chelates. Spectroscopic and magnetic measurements assigned the structural formula of the present violurate metal complexes. The spectroscopic and magnetic investigations along with structural analysis results indicated the square planar geometry of both the Mn(II) and Cu(II) complexes. The structural analysis of the synthesized metal complexes was achieved by processing the PXRD data using specialized software Expo 2014. Spectrophotometeric and viscosity measurements showed that violuric acid and its Mn(II) and Cu(II) complexes successfully bind to DNA with intrinsic binding constants Kb from 38.2 x 105 to 26.4 x 106 M-1. The antiviral activity study displayed that the inhibitory concentrations (IC50) of SARS-CoV-2 by violuric acid and its Mn(II) and Cu(II) complexes are 84.01, 39.58 and 44.86 lM respectively. Molecular docking calculations were performed on the SARS-CoV-2 virus protein and the computed binding energy values are -0.8, -3.860 -5.187 and -4.790, kcal/mol for the native ligand, violuric acid and its Mn(II) and Cu(II) complexes respectively. Insights into the relationship between structures of the current compounds and their degree of reactivity are discussed.(c) 2022 The Author(s). Published by Elsevier B.V. on behalf of King Saud University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Synthesis, characterization, theoretical study and molecular docking studies of some new cobalt(II), chromium(II) and nickel (II) complexes

Three transition metal complexes with general formula [M(L)(2)] (Co = (1), Cr = (2) and Ni = (3)), were synthesized by treating CoCl2/CrCl3 center dot 6H(2)O/NiCl2 center dot 6H(2)O with an ONS-donor Schiff base ligand (HL) derived from the condensation of 3,5-Diiodosalicylaldehyde and 4,4-Dimethyl-3-thiosemicarbazide. The geometry around the centre metal ions was octahedral as revealed by the data collection from spectroscopic studies. The newly synthesized compounds were fully characterized by various physicochemical and spectroscopic methods. DFT calculations were performed on the compounds to get a structure-property relationship. Some global reactivity descriptors like chemical potential (mu), electronegativity (chi), hardness (eta) and electrophilicity index (omega) were also evaluated using DFT method. The ADMET prediction analyses have been explored. Molecular dynamics simulations were also studied. Besides this, to find a potential inhibitor for anti-SARS-CoV-2, metal complexes are also assessed through molecular docking and 3-D visualizations of intermolecular interactions against main protease (M-pro) of SARS-CoV-2 (PDB ID: 7JKV). The molecular docking calculations of the complex (1) into the main protease of SARS-CoV-2 virus (PDB ID: 7JKV) revealed the binding energy of -7.2 kcal/mol with an inhibition constant of 2.529 mu M at inhibition binding site of receptor protein. Complex (2) with SARS-CoV-2 resulted in the binding energy of -7.8 kcal/mol and the inhibition constant of 5.231 mu M. Similarly, complex (3) with SARS-CoV-2 (PDB ID: 7JKV) exhibited the binding energy and the inhibition constant of -7.5 kcal/mol and 3.585 mu M respectively at inhibition binding site of receptor protein. Overall, in silico studies explored the potential role of metal complexes, which would offer new drug candidates against SARS-CoV-2.

Metal-based complexes against SARS-CoV-2.

The first appearance of SARS-CoV-2 is dated back to 2019. This new member of the coronavirus family has caused more than 5 million deaths worldwide up until the end of January 2022. At the moment, and after intensive vaccination programmes throughout the world, the pandemic is still active, whilst new mutations constantly appear. Researchers are working intensively to discover antiviral drugs to combat the severe cases in intensive care units, giving the overloaded hospital units a breather. Alongside various research projects focusing on developing small pharmaceutical molecules, a significant proportion of the research community has shifted towards paying attention to metal drugs. In this small review, we make brief reference to the use of metal drugs in therapeutics and provide some examples of metal drugs that are of extreme interest in the current pandemic. At the same time, we will also examine some of their promising mechanisms of action and possible effectiveness against COVID-19.

Can New Series of Half-sandwich Lanthanum(III), Erbium(III), and Ytterbium(III) Complexes of Organometallic Ferrocenyl Schiff Base Ligands Display Biological Activities as Antibacterial and Anticancer Drugs?

A new series of La(III), Er(III), and Yb(III) complexes were synthesized from ferrocenyl Schiff base ligands (2-(1-((8-aminonaphthalen-1-yl)imino)ethyl)cyclopenta-2,4-dien-1-yl) (cyclopenta-2,4-dien-1-yl)iron (L-1) and (2-(1-((1-carboxyethyl)imino)ethyl) cyclopenta-2,4-dien-1-yl)(cyclopenta-2,4-dien-1-yl)iron (HL2). Complexes were designed, synthesized, and characterized using various spectroscopic techniques. Molar conductance data exposed that the complexes were electrolytes except La(III)-HL2 complex, which was non-electrolyte. IR spectra denoted that Schiff bases were coordinated with transition metal ions in a bidentate manner, N,N donor sites with L-1 and N,O donor sites with HL2. All complexes were octahedral and prepared in a 1:1 molar ratio with the ligands. Thermal behavior of the complexes was studied. The in vitro antibacterial activities of these compounds were evaluated against eight bacterial species such as four Gram positive bacteria (Staphylococcus aureus, Bacillus cereus, Bacillus subtilis, Streptococcus faecalis), and four Gram negative bacteria (Escherichia coli, Pseudomonas aeruginosa, Neisseria gonorrhoeae, Salmonella typhimurium) and results displayed that title compounds are biologically active. Also, they were assessed for their anticancer activities against cell line MCF-7 for breast cancer. Finally, molecular docking studies were tested for all prepared compounds with two different COVID-19 receptors (7BZ5 and 7C8J), also, against 3HB5 receptor of breast cancer. Molecular docking has shown favorable interaction between the title compounds and three protein receptors. This paper affords a manifestation of a novel tradition by which Comments on Inorganic Chemistry starts publishing original research content that, nonetheless, preserves the Journal's identity as a niche for a critical discussion of contemporary literature in inorganic chemistry;for previous manifestations, see Comments Inorg. Chem. 2020, 40, 277-303, and references cited in the thereof.

Coppers film fabrication on glass substrate by complex reduction method for rapid inactivation of SARS-CoV-2 (COVID-19)

A Cu film with the ability to rapidly inactivate the COVID-19 virus was easily fabricated at approximately 23°C on a Na-free glass substrate. The well-adhered Cu films with thickness of approximately 16 μm and surface area of 8.71 10-3 m2 g-1 were obtained by immersion of the glass substrate into an aqueous solution with dissolved Cu (II) complex of ammonia and ascorbic acid. The interface bonded between the film and glass substrate was very strong, such that the film did not peel off even when it was exposed to an ultrasonic wave of 100 mW (42 kHz) in water. The anti-COVID-19 activity in Dulbecco's modified Eagle's medium (DMEM) is effective within 2 h and is faster than that of commercial copper plates. The changes in the relative abundance of Cu2O and CuO crystallines on the Cu film due to DMEM treatment and those in surface morphology were examined by X-ray diffraction peak analysis and field emission-scanning electron microscopy, respectively. The flame atomic absorption analyses of the recovered solutions after DMEM treatment indicated that the Cu ions from the Cu film with DMEM treatment for 1 hour at a concentration of 0.64 ± 0.03 ppm were eluted 2.3 times faster than those from the Cu plate. The rapid elution of Cu ions from Cu2O crystallines on the film in the early stage is the primary factor in the inactivation of the COVID-19 virus, as elucidated from the time dependence of eluted Cu ions by DMEM treatment. Results from thermogravimetric and differential thermal analysis (TG-DTA) of the powder scratched from the Cu film suggested that a trace amount of organic residues remaining in the Cu film was important in the rapid activity. © 2022 World Scientific Publishing Company.

New Achievements for the Treatment of Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) constitutes a heterogeneous group of malignancies that are often aggressive and associated with a poor prognosis. The development of new TNBC treatment strategies has become an urgent clinical need. Diagnosis and subtyping of TNBC are essential to establish alternative treatments and targeted therapies for every TNBC patient. Chemotherapy, particularly with anthracycline and taxanes, remains the backbone for medical management for both early and metastatic TNBC. More recently, immune checkpoint inhibitors and targeted therapy have revolutionized cancer treatment. Included in the different strategies studied for TNBC treatment is drug repurposing. Despite the numerous medications available, numerous studies in medicinal chemistry are still aimed at the synthesis of new compounds in order to find new antiproliferative agents capable of treating TNBC. Additionally, some supplemental micronutrients, nutraceuticals and functional foods can potentially reduce the risk of developing cancer or can retard the rate of growth and metastases of established malignant diseases. Finally, nanotechnology in medicine, termed nanomedicines, introduces nanoparticles of variable chemistry and architecture for cancer treatment. This review highlights the most recent studies in search of new therapies for the treatment of TNBC, along with nutraceuticals and repositioning of drugs.