Synthesis,Characterization, biocidal, Anti-diabetic, Anti-inflammatory and Anti-Cancer(MCF-7) Studies of Schiff base ligand and its metal (II) complexes

A new Schiff base ligand (L1) was prepared from 3-aminoquinoline with 2, 5 dimethoxybenzaldehyde in 1:1 molar ratio. Two different co-ordination of mononuclear metal(II) complexes [(ML1) &(ML1L2)] [ M= Co(II), Ni(II), Cu(II) and Zn(II)] were synthesized & characterized. ML1wereprepared from L1 and metal acetate salts molar proportion One:Two. ML1L2 synthesized from L1, metal salts and 8-hydroxy quinoline (L2) molar ratiois 1:1:1. Elemental analyses, IR, NMR, Electronic spectra, Mass spectra, EPR, SEM and Powder XRD &molar conductivity are need to clarify the structure of synthesized metal(II) complexes. The squareplanar geometry is proposed for CuL1, NiL1, ZnL1, NiL1L2 and ZnL1L2, tetrahedral geometry for CoL1&CoL1L2 and distorted square planar geometry for CuL1L2complex. Powder XRD reveals that L1, ML1& ML1L2 have crystalline nature. Antibacterial activity of Ligand,ML1& ML1L2 were screened against bacterium Gram(+), Gram(-) &antifungal activity was determined against fungus. Theanti-inflammatory and anti-diabetic actions of the L1, CuL1 &CuL1L2complexes were studied. Theanticancer activity of L1, CuL1 and CuL1L2 were studied opposed toMCF-7 using MTT assay method.

Synthesis, characterization, and biological studies of some biometal complexes

Background Metal complexes Cu[C13H8O4N]22, Ni[Cl3H8O4N]23, and Co[C13H8O4N]24 of bioinorganic relevance have been synthesized with the Schiff base ligand 2-furylglyoxal–anthranilic acid (FGAA) [C13H9O4N] 1. All the complexes are well characterized by various spectral and physical methods. The antimicrobial activity of the complexes has been studied against some of the pathogenic bacteria and fungi. Results Results indicate that complexes have higher antimicrobial activity than the free ligand. This would suggest that chelation reduces considerably the polarity of the metal ions in the complexes which in turn increases the hydrophobic character of the chelate and thus enables permeation, through the lipid layer of microorganisms. All the complexes were assessed for their anticancer studies against a panel of selected cancer cells HOP62 and BT474 respectively. Results showed that the complexes are promising chemotherapeutic alternatives in the search of anticancer agents. The fluorescence quenching phenomenon is observed in the Schiff base metal complexes. Conclusion The octahedral transition metal complexes 2, 3, and 4 have been obtained by treatment of ligand 2-furylglyoxal-anthranilic acid (FGAA) 1 with metal acetate. Complexes under investigations have shown antimicrobial, potential anticancer, and the DNA binding studies. Graphical abstract

Design, synthesis and biological evaluation of heterocyclic methyl substituted pyridine Schiff base transition metal complexes

In recent years heterocyclic Schiff base metal complexes attract more attention in biological application and also showing interesting co-ordination chemistry. In this research article a novel heterocyclic methyl-substituted pyridine Schiff base transition metal complexes of Fe(III), Co(III), Cu(II), and Ni(II) have been design and synthesized by reacting metal acetate or metal salts (FeCl3, CoOAc, CuOAc, NiOAc), with substituted heterocyclic ligand. All newly synthesized metalcomplexes were characterized by spectroscopic data and screened for elemental analysis, FT-IR, ESR, Magnetic susceptibility and TGA. The Electronic spectra and magnetic susceptibility measurements indicates that square planer and octahedral geometry of these complexes also suggest their structure in which (N, O) group acts as bidentate ligand. The thermal stability, decomposition rate and thermodynamic parameters of synthesized metal complexes were calculated by Freeman Carroll method. Also the biostatistical data of antimicrobial and anti-oxidant activities of synthesized metal complexes indicates moderate to good results. Graphic abstract

Binding of Divalent Cations to Aqueous Acetate: Molecular Simulations Guided by Raman Spectroscopy

<div> <div> <div> <p>In spite of the biological importance of the binding of Zn2+, Ca2+, and Mg2+ to the carboxylate group, cation-acetate binding affinities and binding modes remain actively debated. Here, we report the first use of Raman multivariate curve resolution (Raman-MCR) vibrational spectroscopy to obtain self-consistent free and bound metal acetate spectra and one-to-one binding constants, without the need to invoke any a priori assumptions regarding the shapes of the corresponding vibrational bands. The experimental results, combined with classical molecular dynamics simulations with a force field effectively accounting for electronic polarization via charge scaling and ab initio simulations, indicate that the measured binding constants pertain to direct (as opposed to water separated) ion pairing. The resulting binding constants do not scale with cation size, as </p><div> <div> <div> <p>the binding constant to Zn2+ is significantly larger than that to either Mg2+ or Ca2+, although Zn2+ and Mg2+ have similar radii that are about 25% smaller than Ca2+. Remaining uncertainties in the metal acetate binding free energies are linked to fundamental ambiguities associated with identifying the range of structures pertaining to non-covalently bound species. </p> </div> </div> </div> </div> </div> </div>

Binding of Divalent Cations to Aqueous Acetate: Molecular Simulations Guided by Raman Spectroscopy

<div> <div> <div> <p>In spite of the biological importance of the binding of Zn2+, Ca2+, and Mg2+ to the carboxylate group, cation-acetate binding affinities and binding modes remain actively debated. Here, we report the first use of Raman multivariate curve resolution (Raman-MCR) vibrational spectroscopy to obtain self-consistent free and bound metal acetate spectra and one-to-one binding constants, without the need to invoke any a priori assumptions regarding the shapes of the corresponding vibrational bands. The experimental results, combined with classical molecular dynamics simulations with a force field effectively accounting for electronic polarization via charge scaling and ab initio simulations, indicate that the measured binding constants pertain to direct (as opposed to water separated) ion pairing. The resulting binding constants do not scale with cation size, as </p><div> <div> <div> <p>the binding constant to Zn2+ is significantly larger than that to either Mg2+ or Ca2+, although Zn2+ and Mg2+ have similar radii that are about 25% smaller than Ca2+. Remaining uncertainties in the metal acetate binding free energies are linked to fundamental ambiguities associated with identifying the range of structures pertaining to non-covalently bound species. </p> </div> </div> </div> </div> </div> </div>

Just Add Water: For Instant and Scalable Conversion of Metal Acetate to Metal-Organic Frameworks

<div><p>MOFs are typically synthesized under harsh conditions that require high pressure and temperature. So, here we necessitating advances in their expedient and scalable synthesis at ambient conditions. Toward that end, the Cu-BDC & Cu-BTC can now be prepared in minutes via a controlled dissolution– crystallization route with divalent metal acetate as a precursor at room temperature, which would be highly desired for industrial implementation and commercialization<br></p></div>

Just Add Water: For Instant and Scalable Conversion of Metal Acetate to Metal-Organic Frameworks

<div><p>MOFs are typically synthesized under harsh conditions that require high pressure and temperature. So, here we necessitating advances in their expedient and scalable synthesis at ambient conditions. Toward that end, the Cu-BDC & Cu-BTC can now be prepared in minutes via a controlled dissolution– crystallization route with divalent metal acetate as a precursor at room temperature, which would be highly desired for industrial implementation and commercialization<br></p></div>

Hybrid Quinoline-Sulfonamide Complexes (M2+) Derivatives with Antimicrobial Activity

Two new series of hybrid quinoline-sulfonamide complexes (M2+: Zn2+, Cu2+, Co2+ and Cd2+) derivatives (QSC) were designed, synthesized and tested for their antimicrobial activity. The synthesis is straightforward and efficient, involving two steps: acylation of aminoquinoline followed by complexation with metal acetate (Cu2+, Co2+ and Cd2+) or chloride (Zn2+). The synthesized QSC compounds were characterized by FTIR and NMR spectroscopy and by X-ray diffraction on single crystal. The QSC compounds were preliminary screened for their antibacterial and antifungal activity and the obtained results are very promising. In this respect, the hybrid N-(quinolin-8-yl)-4-chloro-benzenesulfonamide cadmium (II), considered as leading structure for further studies, has an excellent antibacterial activity against Staphylococcus aureus ATCC25923 (with a diameters of inhibition zones of 21 mm and a minimum inhibitory concentration (MIC) of 19.04 × 10−5 mg/mL), a very good antibacterial activity against Escherichia coli ATCC25922 (with a diameters of inhibition zones of 19 mm and a MIC of 609 × 10−5 mg/mL), and again an excellent antifungal activity against Candida albicans ATCC10231 (with a diameters of inhibition zones of 25 mm and a MIC of 19.04 × 10−5 mg/mL).

Binding of Biologically Relevant Divalent Cations to Aqueous Carboxylates: Molecular Simulations Guided by Raman Spectroscopy

In spite of the biological importance of the binding of Zn2+, Ca2+, and Mg2+ to carboxylate anions, previous experimental and computational studies have reached conflicting conclusions regarding the corresponding binding affinities. Here, we report the first use of Raman multivariate curve resolution (Raman-MCR) vibrational spectroscopy to obtain self-consistent free and bound metal acetate spectra and one-to-one binding constants, without the need to invoke any a priori assumptions regarding the shapes of the corresponding vibrational bands. The experimental results, combined with classical molecular dynamics simulations with a force field effectively accounting for electronic polarization via charge scaling and ab initio simulations, indicate that the measured binding constants pertain to direct (as opposed to water separated) ion pairing. The resulting binding constants do not scale with cation size, as the binding constant to Zn2+ is significantly larger than that to either Mg2+ or Ca2+, although Zn2+ and Mg2+ have similar radii that are about 25% smaller than Ca2+. Remaining uncertainties in the metal acetate binding free energies are linked to fundamental ambiguities associated with identifying the range of structures pertaining non-covalently bound species.