Trease and Evans' pharmacognosy

Some new nano-sized Fe(II), Cd(II) and Zn(II) Schiff base complexes as precursor for metal oxides: Sonochemical synthesis, characterization, DNA interaction, in vitro antimicrobial and anticancer activities.

Three new nano sized Cu(II), Co(II) and Ni(II) complexes of imine ligand derived from the condensation of 2-amino-3-hydroxypyridine and 3-methoxysalicylaldehyde have been prepared and investigated using various chemical techniques such as NMR, elemental analysis, molar conductance, IR, electronic spectra, TGA and magnetic moment measurements. The obtained chemical analysis data showed that the synthesis of 1:1 (metal:ligand) ratio and octahedral geometry was proposed on the basis of magnetic moment and spectral data studies except the Cu(II) complex which is tetrahedral geometry. Nano-sized particles of the investigated complexes were prepared by sonochemistry method. Furthermore, metal oxides nanoparticles were gained by calcination of the prepared corresponding complexes at 500°C and their structures were characterized by powder x-ray and transmittance electron microscopy. Moreover, the free ligand, its complexes and their metal oxides have been checked in vitro against a number of bacteria and fungi in order to assess their antimicrobial activities. In addition to that, DNA binding of the prepared complexes was tested by many routes such as electronic spectra, viscosity and gel electrophoresis. The results showed that the investigated complexes could bind to DNA via an intercalative mode. The cytotoxicity of the Schiff base complexes on human colon carcinoma cells, (HCT-116 cell line) and Breast carcinoma cells, (MCF-7 cell line) showed potent cytotoxicity effect against growth of carcinoma cells compared to the clinically used Vinblastine standard.

Sonochemical synthesis, DNA binding, antimicrobial evaluation and in vitro anticancer activity of three new nano-sized Cu(II), Co(II) and Ni(II) chelates based on tri-dentate NOO imine ligands as precursors for metal oxides.

Synthesis, Characterization and Biological Assay of Salicylaldehyde Schiff Base Cu(II) Complexes and their Precursors

Environmental side effects of the injudicious use of antimicrobials in the era of COVID-19.

A novel Schiff base ligand of type HL was prepared by the condensation of amoxicillin trihydrate and nicotinaldehyde. The metal complexes of Co+2, Ni+2, Cu+2, and Zn+2 were characterized and investigated by physical and spectral techniques, namely, elemental analysis, melting point, conductivity, 1H NMR, IR, UV-Vis spectra, ESR, SEM, and mass spectrometry measurements. They were further analyzed by thermal technique (TGA/DTA) to gain better insight about the thermal stability and kinetic properties of the complexes. Thermal data revealed high thermal stability and nonspontaneous nature of the decomposition steps. The Coats-Redfern method was applied to extract thermodynamic parameters to explain the kinetic behavior. The molar conductance values were relatively low, showing their nonelectrolytic nature. The powder XRD pattern revealed amorphous nature except copper complex (1c) that crystallized in the triclinic crystal system. The EPR study strongly recommends the tetrahedral geometry of 1c. The structure optimization by MM force field calculation through ArgusLab 4.0.1 software program supports the concerned geometry of the complexes. The in vitro antibacterial activity of all the compounds, at their two different concentrations, was screened against four bacterial pathogens, namely, E. coli, P. vulgaris, K. pneumoniae, and S. aureus, and showed better activity compared to parent drug and control drug.

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Metal Complexes of a Novel Schiff Base Based on Penicillin: Characterization, Molecular Modeling, and Antibacterial Activity Study

Bioactivity of some divalent M(II) complexes of penicillin based Schiff base ligand: Synthesis, spectroscopic characterization, and thermal study

The greatest pandemic of the century, COVID-19, is an ongoing global public health problem. With a clinically approved treatment available only for those who are acutely ill and are hospitalized, the control of this disease in the general population is still largely dependent on the preventive measures issued by the World Health Organization. Among the general control measures other than immunization with the COVID-19 vaccines, handwashing with soap and water has been emphasized the most because it is cost-effective and easily accessible to the general public. Studies have reported that soaps offer unique chemical properties that can completely destroy enveloped viruses. However, the general public seems to be still uncertain about whether soaps can shield us from a highly contagious disease such as COVID-19. In an attempt to help eliminate the uncertainty, we analyzed the mechanisms underlying the efficacy of soap and its prospect for preventing the spread of COVID-19. In this paper, we provide an overview of the history and characteristics of the SARS-CoV-2 virus, the current global COVID-19 situation, the possible mechanisms of the deactivation of viruses by soaps, and the potential effectiveness of soap in eliminating coronaviruses including SARS-CoV-2.

https://www.preprints.org/manuscript/202005.0060/v1/download

Fighting the SARS CoV-2 (COVID-19) Pandemic with Soap

A series of three new metal (II) complexes of Schiff base were synthesized from the novel ligand derived from Streptomycin and Amoxicillin in stoichiometric ratio They were characterized by elemental analysis and spectral techniques like IR, 1H NMR, electronic spectrum and mass spectrum IR spectral data suggested that the tetradentate ligand has coordination to metal ions through azomethine nitrogen, glycosidic oxygen and two amine nitrogens Electronic spectral measurement indicated square planar geometry of Ni and Zn-complexes and tetrahedral geometry of Cu-complex with diamagnetic behavior Molar conductivity measurements revealed non-electrolyte nature of the complexes where metal ions have coordination through doubly negative charged anions of the Schiff base The thermal behavior (TGA/DTA) of the complexes was studied and kinetic parameters were determined by Coats-Redfern method XRPD technique revealed monoclinic crystal systems for Ni- and Zn-complexes and hexagonal crystal system for Cu-complex The possible geometries of the metal complexes with their bond length were optimized by MM2 calculations using CsChem3D Ultra-11 program package software Antibacterial sensitivity of the ligand and its metal complexes were assayed in vitro against four bacterial pathogens viz E coli, B subtilis, S aureus and K pneumonia by Kirby Bauer paper disc diffusion method and showed moderate to better potency

/pdf/in-vitro-antimicrobial-screening-of-metal-complexes-of-2gk08d16ha.pdf

In Vitro Antimicrobial Screening of Metal Complexes of Schiff Base derived from Streptomycin and Amoxicillin: Synthesis, Characterization and Molecular Modelling

The discovery of new chemotherapeutics with novel bioactivities and functionalities to fight current emerging diseases has become the most significant research in pharmaceutical science. Schiff bases are versatile pharmacophores that can form complexes by chelation with metals of different oxidation states. Over a few decades of intensive research on metal-based drugs, Schiff base metal complexes have been considered as the active field of research in coordination chemistry, owing to their valuable applications in various fields of science. As therapeutic drugs, they have potential applications as antibiotic, antimicrobial, antitumor, antiviral, anti-inflammatory, analgesic, antifungal, and many more. There has been a global threat of drug resistance in medical science in recent years because most of the pathogenic organisms are developing the ability to deactivate drug substances. For this reason, it requires urgent attention from chemical and pharmaceutical scientists to address the severe challenges of multidrug resistance. This review summarizes the current developments in the last few decades' research on the chemotherapeutic activities of Schiff base metal complexes. \nBIBECHANA 18 (2021) 214-230

/pdf/schiff-base-metal-complex-as-a-potential-therapeutic-drug-in-477n8nd6ax.pdf

Narendra Kumar Chaudhary

Papers

Metal Complexes of a Novel Schiff Base Based on Penicillin: Characterization, Molecular Modeling, and Antibacterial Activity Study

Bioactivity of some divalent M(II) complexes of penicillin based Schiff base ligand: Synthesis, spectroscopic characterization, and thermal study

Fighting the SARS CoV-2 (COVID-19) Pandemic with Soap

In Vitro Antimicrobial Screening of Metal Complexes of Schiff Base derived from Streptomycin and Amoxicillin: Synthesis, Characterization and Molecular Modelling

Schiff base metal complex as a potential therapeutic drug in medical science: A critical review