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The anticancer studies of a Schiff base; (E)‐2((2‐hydroxybenzylidene)amino‐3‐mercaptopropanoic acid (H2L) (obtained from 2‐hydroxybenzaldehyde and L‐cysteine) and its transition metal complexes have been reported. The evaluation of the growth inhibitory action was studied for the compounds against human colon carcinoma (HCT‐116), human hepatocellular liver carcinoma (HEPG‐2), normal melanocytes (HFB‐4) and human breast carcinoma (MCF‐7) cell lines. The obtained results revealed that the Schiff base and its chelates are active against human hepatocellular liver carcinoma (HEPG‐2) cell lines. The powder X‐ray diffraction analysis for the compounds was carried out through Phillips X′Pert High score software. The density functional theory computation for ligand and Co(II), Ni(II) and Cu(II) metal complexes were made to understand the mode of bonding by GAUSSIAN 03 rev. A.01 programme. The quantitative structure‐activity relationship investigation was performed by using HyperChem Professional 8.0.3 software to understand the biological potency of the ligands. Moreover, a docking analysis using iGEMDOCKv2.1 software was carried out against the kinase enzyme PDB ID:1fvv. [ABSTRACT FROM AUTHOR]

The azo ligand obtained from the diazotization reaction of 2-aminobenzothiazole and 4-nitroaniline yielded a novel series of complexes with Co(II), Ni(II), Cu(II), and Zn(II) ions. The complexes were investigated using spectral techniques such as UV-Vis, FT-IR, 1H and 13C NMR spectroscopic analyses, LC-MS and atomic absorption spectrometry, electrical conductivity, and magnetic susceptibility. The molar ratio of the synthesized compounds was determined using the ligand exchange ratio, which revealed the metal-ligand ratios in the isolated complexes were 1:2. The synthesized complexes were tested for antimicrobial activity against S. aureus, E. coli, C. albicans, and C. tropicalis bacterial species. Additionally, their binding affinities were predicted using molecular docking analysis, and their pharmacokinetic and drug-likeness properties were evaluated. [ABSTRACT FROM AUTHOR]

A novel series of Schiff base metal complexes of the type [M(L)2].nH2O, where L= 2-(α-methylsalicylidenehydrazino) benzimidazole (L1), 2-(α-phenylsalicylidenehydrazino)benzimidazole (L2), 2-(o-vanillinidenehydrazino)benzimidazole (L3), M = Cu(II), Co(II), Ni(II) and Zn(II), have been synthesized and characterized. The results are in consistent with tridentate chelation of ligand with azomethine nitrogen, ring nitrogen and a deprotonated phenolic oxygen atom. All these compounds have been screened for their antibacterial activities against B. subtilis, B. stearothermophilus, E. coli and S. typhi. [ABSTRACT FROM AUTHOR]

The ongoing COVID‐19 pandemic caused by SARS‐CoV‐2 is associated with high morbidity and mortality. This zoonotic virus has emerged in Wuhan of China in December 2019 from bats and pangolins probably and continuing the human‐to‐human transmission globally since last two years. As there is no efficient approved treatment, a number of vaccines were developed at an unprecedented speed to counter the pandemic. Moreover, vaccine hesitancy is observed that may be another possible reason for this never ending pandemic. In the meantime, several variants and mutations were identified and causing multiple waves globally. Now the safety and efficacy of these vaccines are debatable and recommended to determine whether vaccines are able to interrupt transmission of SARS‐CoV‐2 variant of concern (VOC). Moreover, the VOCs continue to emerge that appear more transmissible and less sensitive to virus‐specific immune responses. In this overview, we have highlighted various drugs and vaccines used to counter this pandemic along with their reported side effects. Moreover, the preliminary data for the novel VOC "Omicron" are discussed with the existing animal models. [ABSTRACT FROM AUTHOR]

• Syntheses of new Co(II), (C1); Ni(II), (C2); Cu(II), (C3) and Zn(II), (C4) complexes. • Characterization of the new complexes using various physicochemical and analytical techniques. • The free ligand and its metal complexes had been applied as disperse dyes on cotton fabrics. • The free ligand and its metal complexes were in vitro investigated for their antimicrobial activity. • Theoretical studies (DFT and molecular docking) were performed. Four Co(II), (C1); Ni(II), (C2); Cu(II), (C3) and Zn(II), (C4) chelates have been synthesized with 1-(4-((2-amino-5‑methoxy)diazenyl)phenyl)ethanone ligand (L). The produced compounds have been identified by using spectral studies, elemental analysis (C.H.N.O), conductivity and magnetic properties. The produced metal chelates were studied using molar ratio as well as sequences contrast types. Rate of concentration (1 ×10−4 - 3 ×10−4 Mol/L) sequence Beer's law. Compound solutions have been noticed height molar absorptivity. The free of ligand and metal chelates had been applied as disperse dyes on cotton fabrics. Furthermore, the antibacterial activity of the produced compounds against various bacteria had been investigated. For the gained datum, a tetrahedral geometrical structure has been suggested for each primed complex. Molecular docking investigation was carried out to ascertain the inhibitory action of the studied compounds against 1HNJ protein, the target enzyme for the antimicrobial agents. The findings showed that, when compared to other compounds, (C1) has the highest binding affinity. Therefore, these molecules might make good candidates for antimicrobials. The quantum chemical parameters are calculated, and the molecular structure complexes were theoretically optimized. [ABSTRACT FROM AUTHOR]

Ureas and thioureas, otherwise known as carbamides and thiocarbamides, respectively, are rich sources of nitrogen. Urea has a wide range of applications in agriculture, the chemical industry, and automobile systems, and is an important chemical in medical uses. Thiourea, an organosulfur compound, has long been known as an important reagent in organic synthesis, and has been employed in textile processing, used as a source of sulphides, and acts as a precursor in the synthesis of several heterocyclic compounds. The exceptional ligating properties of these compounds enable them to form a large number of complex compounds with transition metals, a vast majority of which find abundant applications in potential areas. This has stimulated researchers to explore novel applications of the synthesized ligands and the metal complexes thereof. This review presents a report of the studies on the biological activities, sensor properties, opical nonlinear properties, corrosion inhibitior potential, and catalytic activities of these compounds and their metal complexes. [ABSTRACT FROM AUTHOR]

Abstract A novel series of complexes of the type, [ML 2 ].nH 2 O, [where L = 2-(α-methyl salicylidene–2′-imino) aminobenzo thiazole (HMAB), 2-(α-phenyl salicylidene–2′-imino) aminobenzo thiazole (HPAB), 2-(o-Vanillidene–2′-imino) amino benzothiazole (HVAB)] have been reported. These Schiff bases and their transition metal complexes were fully characterized by several physico-chemical and spectral techniques, which revealed the tridentate chelation of ligand. The DFT calculations of these reported compounds were made to obtain bonding inside the structure by GAUSSIAN 03 programme platforms. The QSAR study was performed by HyperChem Professional 8.0.3 software to explain the biological effeteness of the ligands. A docking analysis using the AutoDock Vina software was carried out to understand the binding pattern of the investigated compounds towards target proteins CYP121 and CYP51 from Mycobacterium tuberculosis. Furthermore, all the compounds have been reported to exhibit significant antifungal activity when tested against Aspergillus flavus and Aspergillus niger. Graphical abstract Image Highlights • Schiff base ligands are prepared from 2-hydrazinobenzothiazole. • The metal complexes are synthesized and characterised by spectroscopic, thermal and X.R.D. powder pattern. • Molecular modelling of the ligands and their Cu & Zn complexes are made to understand the mode of bonding. • Molecular docking, QSAR and antifungal study were ascertained to verify the bio-potency of the compounds. [ABSTRACT FROM AUTHOR]

Schiff bases are stable imines containing C=N, where N is bonded to an alkyl or aryl group, but not with hydrogen and are prepared by condensation of aliphatic or aromatic primary amine with carbonyl compounds. They have the general formula R1R2C = NR3, where R3 ≠ H. The presence of the basic donor N atom and the stability of the imine function render Schiff bases as the most favored ligands that have the ability to stabilize metal ions in different oxidation states. The chelating environment in a Schiff base profoundly influences the electron distribution in the coordination sphere of metal in a complex and thereby regulates the property of the compounds in a big way. The structural diversity in some of the metal complexes with multidentate Schiff base ligands has triggered a wide range of applications of this class of compounds in sensors, catalysis, biology, medicines, and photonics. This review compiles the synthesis and biological activities (antimicrobial, antioxidant, anticancer, antitubercular, DNA interaction studies) of benzaldehyde-based Schiff bases and their metal complexes. [ABSTRACT FROM AUTHOR]

• A series of mixed-ligand complexes was synthesized by using a Schiff base as main ligand and nicotinamide as secondary ligand. • The Schiff base was prepared by the interaction of ampicillin drug and 4-chlorobenzophenone. • The DFT calculations and molecular docking analysis were carried out. • The synthesized complexes exhibited significant antimicrobial activity. • The drug-likeness and toxicity of the compounds were also performed. A novel series of mixed-ligand complexes of the type, [ML 1 (L 2) 3 Cl x [M= Cr(III), Fe(III), Co(II),Ni(II), Cu(II), Cd(II) and Hg(II), n = 2, 3], was synthesized using Schiff base (HL 1) as main ligand, nicotinamide (L 2) as secondary ligand, and the corresponding metal ions in 1:3:1 molar ratio. The main ligand, HL 1 was prepared by the interaction of ampicillin drug and 4-chlorobenzophenone. The synthesized mixed ligand complexes were characterized by elemental analysis, UV-Vis, FT-IR,1H-NMR,13C-NMR and TG/DTG studies. In the mixed-ligand complexes, the Schiff base ligand, HL 1 showed coordination to the central metal ion in tridentate manner via azomethine nitrogen, β-lactam ring oxygen and deprotonated carboxylic oxygen atoms, whereas the secondary ligand L 2 (nicotinamide, Nam) coordinated through pyridine nitrogen atoms. The synthesized complexes exhibited significant antimicrobial activity when evaluated against P. pseudomonas, E. coli, S. aureus and B. subtilis microbes. The DFT calculations were also carried out to ascertain the bonding insights into the structure. In addition, molecular docking analysis was performed carried out to know the interactions between complexes and their probable binding sites in penicillin binding protein (PBP2). Moreover, drug-likeness and toxicity of the compounds were also performed to predict the suitability of the complexes as drugs. Image, graphical abstract [ABSTRACT FROM AUTHOR]