Synthesized Schiff Base Ligand Research Articles

Antibacterial, Antidiabetic, Antioxidant and DNA cleavage studies of novel N(3-(bis(pyridine-2ylmethyl)amino)-2-hydroxypropyl) benzene sulphonamide ligand

The novel N (3-(bis(pyridine-2ylmethyl)amino)-2-hydroxypropyl) benzene sulphonamide ligand have been synthesized from 1,3-Diamino-propan-2-ol. The structure of the ligand was confirmed by Mass spectroscopy and 1H NMR spectroscopy. The synthesized Schiff base ligand was tested for their in vitro anti bacterial action with Gram-positive and negative bacteria. The anti-diabetic activities have been tested with α-amylase inhibition method and antioxidant effect of the compound was established using DPPH method. Thus all the studies reveals that the synthesised Schiff base compound has significant antibacterial, antidiabetic and antioxidant activities. The DNA cleavage studies shown that, the DNA binding nature of the ligand was appreciably good. The Molecular docking characteristics were supported that the binding approach of the effective inhibitors with the active site of enzymes.

Synthesis, Electrochemical Studies and Theoretical Calculations of Sulfo‐Schiff Bases

AbstractIn this study, two different water‐soluble Schiff base ligands as sodium(Z)‐3((2,5‐dihydroxybenzylidene)amino)benzene sulfonate (SLI) ve sodium (Z)3‐((3,4‐dihydroxybenzylidene)amino)benzene sulfonate (SLII) were synthesized as a result of the condensation reaction of 3‐aminobenzenesulfonicacid containing sulfo group with 2,5‐dihydroxybenzaldehyde and 3,4‐dihydroxybenzaldehyde, respectively. The chemical structures of the synthesized Schiff base ligands were characterized by melting point determination, elemental analysis, FT‐IR and 1H‐NMR techniques. Electrochemical behaviors of synthesized SLI and SLII ligands were examined by cyclic voltammetry technique against Ag/AgCl/KCl(sat) at the glassy carbon electrode in Britton Robinson buffer solution, pH 5.0. Electrode surfaces modified with SLI and SLII ligands were characterized by cyclic voltammetry technique in the presence of ferrocene and potassium hexacyanoferrate (III) redox probes, water contact angle measurement, scanning electron microscope and atomic force microscope and compared with the data of the bare glassy carbon electrode surface. Theoretical calculations of SLI and SLII ligand were performed with Density Functional Theory (DFT) and compared with experimental results.

Synthesis, structural characterization and biological applications of mono- and binuclear Cu(II) and Ni(II) complexes with N2O2 Schiff bases

The present work aims to synthesize and characterize new Schiff base metal complexes (Cu(II) and Ni(II)) derived from 4,5-Dichloro-o-phenylenediamine and 3,5-Dichloro-2-hydroxyacetophenone. The synthesized Schiff base and their complexes have been characterized with the support of more than a few standard physicochemical techniques such as elemental analysis, spectroscopic, thermal, and cyclic voltammetry studies. Further the molecular structures are ascertained by computational methods like density functional theory (DFT) methods. The newly synthesized Schiff base ligand acts as ONNO donor tetradentate chelate and coordinated through an azomethine nitrogen and phenoxo oxygen atom to the Cu(II) and Ni(II). Moreover, all the newly prepared compounds exhibit moderate biological activity such as antibacterial. The synthesized compounds were screened for their antibacterial by the disc agar diffusion method. Spectral analysis exhibits square planar geometry for Cu(II) & Ni(II) mono and binuclear complexes. The antimicrobial results indicate that the homo binuclear copper (II) complex was more active than the other mono and binuclear complexes. The theoretical DFT calculations were applied to verify the molecular geometry of chelators and their complexes. The DFT optimized geometries of the complexes are in agreement with experimental observations.

Novel Ni(II) and Zn(II) Schiff base metal chelates as promising DNA binder, Antioxidant and Antifungal agents

<p>Schiff base ligands and their 3d-metal chelates have gained significant attention due to various applications in various scientific platforms. Due to their chelating propensity, they possess a wide range of biological, biochemical, catalytic, clinical, dying, and pharmacological properties.<strong> </strong>Here, in present studies,<strong> </strong>two novel Ni(II) and Zn(II) transition metal chelates have been synthesized by condensing their metal salts with Schiff base ligand 4-chloro-2-(2,5-dimethoxybenzylideneamino)-5-nitrophenol<strong> </strong>originated from 2,5-dimethoxybenzaldehyde and 2-amino-4-chloro-5-nitrophenol. The synthesized Schiff base ligand and its metal chelates have been Spectro-chemically examined by FT-IR, UV-Vis absorption spectroscopy, Mass Spectrometry, <sup>1</sup>HNMR, Thermogravimetric analysis (TGA) and Powdered-XRD. These compounds are biologically reactive and exhibit antifungal, antioxidant, and DNA-binding activity. The Ni(II) metal chelate gives better biological activity than the Zn(II) metal chelate and parent Schiff base ligand.</p>

Studies of the nonlinear optical properties of a synthesized Schiff base ligand using visible cw laser beams

The synthesized Schiff base ligand (compound Z1) is analyzed by IR, mass, 1HNMR, and 13CNMR spectroscopies. Computational chemical modeling is performed to examine the geometry optimization and molecular structure of compound Z1 by using the DFT/ WB97XD/6-31+G(d,p) method. The parameters HOMO–LUMO energies with nonlinear optical (NLO) properties are computed. The results indicate good agreement between experimental and theoretical data, so that compound Z1 to have good NLO properties. The NLO properties of the compound Z1 are examined under excitation with a 473 nm, cw, low power laser beam via two techniques, viz., diffraction patterns (DPs) and the standard Z-scan techniques. As high as 3.03 × 10−11 m2 W−1 of the compound Z1 of the nonlinear refractive index (NLRI), n2, is obtained via the DPs. Both static and dynamic all –optical switching (SAOS and DAOS) are tested using 473 nm and 532 nm cw low power laser beams.

Synthesis, Characterization and Bioactivity Evaluation for Some Metal Ions Complexes with New Ligand Derived from 2-hydroxy-1- napthaldehyed

تم مفاعلة قاعدة شيف المُحضرة حديثًا (E)-2-((2-phenylhydrazono)methyl)naphthalen-1-ol (مشتق فينيل هيدرازين) مع كل من الأيونات المعدنية التالية: Ni2 + ، Cu2 + Zn2 + , Cd2+للحصول على معقدات فلزية بأشكال هندسية مختلفة. تم الاستدلال عن تكوين معقدات قاعدة شيف وأيضًا قاعدة شيف الأصلية باستخدام كروماتوغرافيا السائل-مطياف الكتلة التي تتفق مع الكتلة المولية التي تم الحصول عليها نظريا، أثبت دراسات مطيافية الاشعة تحت الحمراءحدوث التناسق من خلال N من azobenzene و اوكسجين مجموعة ال OH من خلال ملاحظة الانزياح في قمةazomethines والظهور كل من قمتيM-N و N-O. علاوة على ذلك ، يمكننا أيضًا أن نكتشف بواسطة هذا الجهاز وجود جزيء ماء داخل مجال التناسق. كشفت أطياف UV-Vis لجميع النتائج عن حدوث تناسق من خلال ملاحظة الانزياح في الانتقالات الإلكترونية التي حدثت في الليكاند في المنطقة فوق البنفسجية. تثبت قياسات TGA و DSC لكل من الليكاند و معقد النيكل أيضًا تكون المعقد ووجود جزيء ماء داخل مجال التناسق. بالإضافة إلى ذلك ، كانت نتائج التوصيلية المولارية و الامتصاص الذري اللهبي FAA أقرب إلى نتائج المحسوبة نظريا. أعطت نتائج التشخيص معقدات أحادية النواة وسلوك ثنائي السن واشكال هندسية رباعي السطوح لجميع المعقدات. اعتمادا على خاصية المضادات الحيوية لقاعدة شيف ومعقداتها ، قمنا بدراسة الفعالية الحيوية لقاعدة شف ومعقداتها كما مفصل في المخطوطة.

Investigating spectroscopic properties, biological effects, and molecular docking studies of synthesized Schiff base metal complexes

In this current investigation, we have accomplished the synthesis of a Schiff base ligand termed (E)-4-methyl-N′-(2,4,5-trimethoxybenzylidene)benzohydrazide (HL) through a reversible condensation reaction, which engaged a carbonyl compound and a primary amine. This synthesized Schiff base ligand, HL, served as the foundation for the preparation of two metal complexes, namely, M1L (Cu complex) and M2L (La complex). To characterize these compounds, we employed various analytical techniques, including thermogravimetric studies, elemental analysis, powder X-ray diffraction, FT-IR spectroscopy and 1H NMR. The examination of powder X-ray diffraction data provided valuable insights into the crystalline structures of the Cu and La complexes. These shifts are indicative of structural changes in the complexes. Our electronic spectrum analysis revealed the pivotal involvement of the ligand in promoting charge transfer processes, substantiated by an increased concentration of charge transfer transitions observed when the ligand was present. Additionally, we evaluated the antibacterial efficacy of the Schiff base ligand HL and its metal complexes (Cu, La) against a spectrum of bacteria, encompassing both gram-positive (Bacillus subtilis, Enterococcus faecalis) and gram-negative (Escherichia coli) strains. In the current investigation, we utilized molecular docking techniques to explore the interactions between the synthesized HL and its M1L and M2L complexes with protein receptor molecules. These results highlighted the favorable binding energies and stable interactions of these compounds with the protein receptor, M1L displayed notably more stable interactions and lower binding energy compared to M2L. This suggests that M1L may have a stronger potential impact on the free binding energy and molecular interactions.

Synthesis and Characterization of Biopotent Transition Metal Complexes of Schiff Base 2-{(1)-1-[2-(1,3-Benzothiazol-2-yl)hydrazinylidene]ethyl}-6,10b-dihydro-3H-benzo[f]chromen-3-one and their Biological Evaluation

Three transition metal(II) complexes (M = Co/ Zn/Pd) were synthesized by using a newly synthesized Schiff base ligand 2-{(1E)-1-[2-(1,3-benzothiazol-2-yl)hydrazinylidene]ethyl}-6,10b-dihydro-3H-benzo[f]chromen-3-one (L) by conventional method. The structure of the compounds were determined by physical and analytical techniques like UV-visible, FT-IR, 1H and 13C NMR and mass spectroscopic techniques and the crystallinity and inter-planar distance of the complexes were confirmed by XRD. The electron density in HOMO and LUMO was determined by DFT studies. The studies of electronic spectra and measurements of magnetic susceptibility suggest that Co(II) complex shows an octahedral geometry, Pd(II) complexes show square planar geometry and (ZnL2Cl2) complex shows tetrahedral geometry. The molar conductivity results suggested the non-electrolytic nature of the metal(II) complexes. The synthesized compounds was tested against antibacterial activity for Gram-positive and Gram-negative bacteria. The molecular docking study demonstrated that the ligand and its metal(II) complexes possess antibacterial and anticancer properties, and the results showed that the compounds were effective against the microorganisms that were examined. Furthermore, the results found that metal(II) complexes provided enhanced immunity against cancer cell lines.

Investigation on Biological Activities of Thiosemicarbazide Derived Schiff Base-Metal Complexes

A Schiff base ligand was synthesized via the condensation reaction of thiosemicarbazide and salicylaldehyde. A series of transition metal complexes of VO(IV), Ni(II), Cu(II), and Zn(II) were obtained by the complexation reaction with the synthesized Schiff base ligand. The Schiff base ligand and its metal complexes were characterized by UV-Vis and FTIR spectroscopy, TGA-DTA, and some physical measurements. FTIR spectral studies showed that the NOS donor ligand coordinated to the metal ions through the N of azomethine group, S of thiolate, and O of deprotonated hydroxyl group. Molar conductance values indicated non electrolytic nature of the complexes. Magnetic moment values coupled with electronic spectral data exhibited the geometrical structure of the complexes. The Schiff base and its complexes were exposed to disinfectant studies tested by using the disc diffusion method. All the synthesized compounds exhibited moderate to strong antibacterial activity. The copper complexes showed more antibacterial activity than other complexes and Schiff bases. All the Synthesized complexes showed a good cytotoxic activity.

Synthesis, Characterization, Investigation of Anticancer Activity and Molecular Docking Studies of N2O2 Type Schiff Base Ligand and Metal Complexes

AbstractSchiff base ligands and their metal complexes play a great important role in pharmaceutical sciences because of their wide and significant activities. They are versatile pharmacophores for the design and discovery of many drugs. In this study, a Schiff base ligand and its complexes were synthesized. Some spectroscopic techniques such as FT‐IR, 1H‐NMR, 13C‐NMR, XRD, SEM, and UV‐Vis were used for structural characterization. Antiproliferative activities of the synthesized ligand and complexes were investigated on the human breast (MCF‐7) and colon (HT‐29) cancer cell lines by XTT [2,3‐Bis(2‐methoxy‐4‐nitro‐5‐sulfophenyl)‐2H‐tetrazolium] method. The obtained data showed that the ligand and complexes exhibited dose‐dependent and cell‐selective in vitro antiproliferative activity on the tested cell line. In addition, it was determined that complexes showed statistically higher cytotoxic activity compared to the ligand. The binding parameter values and the important amino acids in the binding site were determined between the possible lead compounds synthesized by molecular docking from in silico approaches and the target. A molecular docking study of the cobalt complex was performed against Bcl‐2 (PDB ID:4IEH) and DNA recognition (PDB ID:423D) targets. In conclusion, these data show that the synthesized Schiff base ligand and metal complexes have the potential to be evaluated as a chemotherapeutic agent.

Novel terephthalaldehyde bis(thiosemicarbazone) Schiff base ligand and its transition metal complexes as antibacterial Agents: Synthesis, characterization and biological investigations

The synthesis and structural characterization of mixed ligand metal complexes from terephthalaldehyde bis(thiosemicarbazone) (TPTSC) (L1) and alanine (L2) by using ultrasonication are reported. The ligand and their transition metal complexes were characterized on the basis of their elemental, FT-IR, magnetic moment, molar conductance, mass spectra, and SEM analysis. The mixed ligand complexes are in the ratio 2:1:2 [M:L1:L2] ratio as found from the elemental analyses and found to have the formulae [M2L1(L2)2].nH2O where M = Co(II), Ni(II), Cu(II), Cd(II) and Zn(II), L1 = TPTSC and L2 = alanine. The molar conductance data show that complexes are non-electrolytes. FT-IR spectra show that the Schiff base is coordinated to the metal ions in a bidentate manner with N and S donor sites of the terephthalaldehyde bis(thiosemicarbazone) and second ligand alanine coordinated to the metal ions via its N and O of amino acid. The geometrical structure of these complexes is found to be tetrahedral. The antimicrobial activity of the synthesized Schiff base ligand and mixed-ligand metal complexes have been screened against gram-positive and gram-negative bacteria and two fungi species were tested. Mixed ligand complexes exhibited significant antibacterial activity against Klebsiella Pneumoniae, Salmonella typhi, Enterococcus Faecalis, Staphylococcus aureus, Escherichia coli and the fungi Aspergillus flavus and Aspergillus niger. Further, these compounds have been screened for their anticancer activity using Human Breast Cancer Cell Line MDA-MB-231.

New metal-organic framework coated sodium alginate for the delivery of curcumin as a sustainable drug delivery and cancer therapy system

The utilization of biocompatible drug delivery systems with extended drug release capabilities is highly advantageous in cancer therapy, as they can mitigate adverse effects. To establish such a biocompatible system with prolonged drug release behavior, researchers developed an innovative drug carrier. In this study, a sustainable approach was employed to synthesize a new zinc-based metal-organic framework (Zn-MOF) through the reaction between synthesized Schiff base ligands and zinc ions. Comprehensive analyses, including FT-IR, XRD, SEM, BET surface area, and TGA techniques, were employed to thoroughly characterize the frameworks. Following comprehensive characterization, curcumin (CUR) was loaded onto the Zn-MOF, resulting in CUR entrapment efficiency and loading capacity of 79.23 % and 26.11 %, respectively. In vitro evaluations of CUR release from CUR@MOF exhibited controlled release patterns, releasing 78.9 % and 50.0 % of CUR at pH 5.0 and pH 7.4, respectively. To mitigate initial burst release, a coating of the biopolymer sodium alginate (SA) was applied to CUR@Zn-MOF. In vitro CUR release tests indicated that SA/CUR@Zn-MOF outperformed pristine CUR@Zn-MOF. The release of CUR conformed to the Korsmeyer-Peppas model, displaying non-Fickian diffusion. Furthermore, an in vitro cytotoxicity study clearly demonstrated the potent anti-tumor activity of the synthesized CUR@Zn-MOF attributed to its controlled release of CUR. This led to the induction of apoptotic effects and cell death across HeLa, HEK293, and SH-SY5Y cell lines. These findings strongly suggest that the developed pH-sensitive carriers hold remarkable potential as targeted vehicles for drug delivery in cancer therapy.

Antimicrobial activities and docking studies of new Schiff base ligand and its Cu(II), Zn(II) and Ni (II) Complexes: Synthesis and Characterization

New Schiff base ligand (E)-2-(((7-chloro-2-hydroxyquinolin-3-yl) methylene) amino)-3-phenylpropanoic acid was synthesized using 2,7-dichloroquinoline-3-carboaldehyde and Phenylanine in ethanol. Using new ligand Copper, Zinc and Nickel complexes were also synthesized and characterized using FTIR, UV–Vis, 1H NMR, 13C NMR, TGA-DTA, and pXRD spectroscopic techniques. From its FTIR spectra, the synthesized Schiff base ligand was verified to be a tridentate ligand containing ONO active binding sites. To evaluate the Schiff base and its metal complexes' antibacterial properties, the disc diffusion method was employed. The antibacterial activity the ligand at a concentration of 100 µg/ml against B. cereus, S. aureus, E. coli, and S. typhi were found to be 10.00 ± 0.41, 6.05 ± 0.21, 8.00 ± 0.408, and 7.17 ± 0.236, respectively, whereas its antifungal activity against C. albinas was found to be 11.25 ± 0.204. Zinc complex showed antibacterial activities against B. cereus (9.33 ± 0.62), S. aureus (12.08 ± 0.42), E. coli (9.50 ± 0.40), S. typhi (6.75 ± 0.20), C. albinas (10.33 ± 0.24) at a concentration of 100 µg/ml whereas the nickel complex exhibited a bit lower activities against B. cereus (6.05 ± 0.22), S. aureus (6.58 ± 0.11), E. coli (6.08 ± 0.11), S. typhi (6.50 ± 0.22), C. albinas (7.50 ± 0.25) at a concentration of 100 µg/ml. On the other hand, the copper complex showed relatively highest antibacterial activity against B. cereus (18.67 ± 0.41), S. aureus (25.05 ± 0.41), E. coli (21.08 ± 0.31), S. typhi (22.05 ± 0.07), and the antifungal activity against C. albinas was 24.08 ± 0.43 than the other two complexes and the ligand. The overall results showed that the copper complex was found to have good antibacterial and antifungal activities. This is mostly caused by its small crystalline size (29.7 nm), which was inferred from the pXRD results.

Exploring the novel aryltellurium(IV) complexes: Synthesis, characterization, antioxidant, antimicrobial, antimalarial, theoretical and ADMET studies

The current research study is focused on biological efficacy of newly synthesized Schiff base ligand 1,1′-(ethane-1,2-diylbis(azanylylidene))bis(methanylylidene))bis(naphthalen-2-ol) (HNED) and its aryltellurium(IV) complexes. The synthesized compounds were comprehensively characterized by physical and spectral investigations such asmolar conductance, Powder-XRD, EDAX, elemental, TGA-DTG analysis, mass, FT-IR, UV–Vis, 13C NMR and 1H NMR spectroscopy. The molecular and electronic structural characteristics of the synthesized compounds were explored by theoretical chemical estimations which was based on density functional theory (DFT). The outcome of the spectroscopic and theoretical data revealed that the Schiff base HNED was coordinated with tellurium ion through oxygen and nitrogen atoms, suggesting distorted octahedral geometry of complexes. The compounds displayed mild to strong antimicrobial activity against numerous microbial species, with the growth inhibitory activities of the complexes being greater than those of the Schiff base. Complexes 6c and 6f exhibited the highest scavenging ability. Complex 6a exhibited the highest efficiency in inhibiting malarial malformation. In silico molecular docking was executed to explore the binding interaction and binding energies of compound against the active site of the various receptors (3MZF, 4DXD, 3Q70 and 2GHU). The ADMET results indicated that the synthesized compounds have favorable drug-like behavior. This study suggest that the complexes may act as promising candidates for infection ailments.

Synthesis, Hirshfeld surface analysis, thermal, and selective α-glucosidase inhibitory studies of Schiff base transition metal complexes

Abstract A synthesized Schiff base ligand 4-{(Z)-[(2-hydroxy-1-naphthyl)methylene]amino}-4-antipyrene (H-NAPP) was confirmed by single crystal diffraction analysis. The H-NAPP was crystalized in the P 21 21 21 space group and orthorhombic crystal system. The Schiff base ligand H-NAPP bears potential donor sites and therefore it was reacted with transition metal ions Co2+, Ni2+, Cu2+, and Zn2+ to yield respective metal complexes. All reaction products were investigated by elemental analyses and IR spectroscopic techniques. The combined spectroscopic characterizations revealed the distorted square planar geometries for all the synthesized metal complexes. The metal complexes were further studied for their thermal stabilities using TG techniques and proved to be thermally cleaved in the temperature range of 30–1,000°C in air. Pseudo-mirrored 2D fingerprint plots were used for the short interatomic interactions in the crystal structure. The major short interatomic interactions involve the hydrogen bonding which covers the Hirshfeld surfaces {H···H, O···H and C···H}. The ligand and complexes were investigated for a potential α-glucosidase inhibitory activity. While relatively inactive throughout, some notable differences were observed and, surprisingly, the ligand was found to be more active than its complexes.

Biological and Computational Investigation of Transition metal(II) Complexes of 2-phenoxyaniline-based Ligands

Aim: In the 21st century, we are witness of continuous onslaughts of various pathogen deformities which are a major cause of morbidity and mortality worldwide. Therefore, to investigate the grave for these deformities, antioxidant, anti-inflammatory and antimicrobial biological activities were carried out against newly synthesized Schiff base ligands and their transition metal complexes, which are based on newly synthesized 2-phenoxyaniline and salicylaldehyde derivatives. Materials & methods: The synthesized compounds were characterized by various physiochemical studies, demonstrating the octahedral stereochemistry of the complexes. Results: The biological assessments revealed that complex 6 (3.01 ± 0.01 μM) was found to be highly active for oxidant ailments whereas complex 14 (7.14 ± 0.05 μM, 0.0041–0.0082 μmol/ml) was observed as highly potent for inflammation and microbial diseases. Conclusion: Overall, the biological and computational studies demonstrate that the nickel(II) complex 14 can act as an excellent candidate for pathogen deformities.

Synthesis and characterization of some transition and inner transition mixed ligand complexes derived from Schiff base ligand and o-aminophenol

By the condensation reaction of benzophenone with naphthalene-1,8-diamine, a bidentate NN Schiff base ligand (L) was obtained. The preparation and structural characterization of mixed ligand chelates derived from Schiff base ligand as a primary ligand and o-aminophenol (o-AP) as a secondary ligand, were also reported. The synthesized Schiff base ligand and its transition and inner transition mixed ligand chelates were characterized based on elemental analyses, FT-IR, mass, 1H-NMR, UV-Vis., molar conductivity and magnetic studies. Thermogravimetric studies were also investigated to determine the thermal stability and degradation of the metal complexes. An octahedral geometry was suggested for all complexes based on spectroscopic and magnetic studies. The surface morphology of the Schiff base ligand and Mn(II) complex confirmed their nano-size. The mass spectra of Schiff base ligand and Er(III) mixed ligand complex pointed out the fair agreement between the calculated and found values. In-vitro antimicrobial activities of Schiff base ligand, o-aminophenol and the mixed ligand complexes were investigated against different pathogenic bacterial and fungal species. The anticancer activity of the new compounds had been also studied towards breast cancer (MCF-7). Molecular docking of the Schiff base ligand was also reported.

Investigating of the anticancer activity of salen/salophen metal complexes based on graphene quantum dots: Induction of apoptosis as part of biological activity

This research work is the first report on the synthesis and stabilization of [Fe-Salophen] and [Fe-Salen] complexes by two methods of surface modification and anchoring of synthesized Schiff base ligand on the surface of graphene quantum dots (GQDs). The GQDs contain oxygenated functional groups that can act as non-radiative electron-hole recombination centers. Therefore removing these oxygen functional groups may improve quantum yield by reducing or deactivating the surface. In this work, GQDs with the amine functional group were synthesized with a quantum yield of 37.48%. The physicochemical properties of GQDs were investigated by Ultraviolet–visible (UV–Vis) and fluorescence spectroscopies, Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), Powder X-ray diffraction (PXRD), Transmission electron microscope (TEM). The synthesis of GQDs-[Fe-Salen] and GQDs-[Fe-Salophen] was evaluated by FT-IR, Inductively coupled plasma atomic emission spectroscopy (ICP-AES) and Energy dispersive X-Ray analysis (EDX) analyses. Then, using MTT- assay, annexin V-FITC/PI, DAPI staining and cellular uptake assays, the biochemical activity of these complexes on the MCF7 cell line was investigated. The results shows that GQDs-[Fe-Salen] and GQDs-[Fe-Salophen] affect the survival of MCF7 cancer cells and, by nuclear fragmentation cause 35.77% and 19.41% of early apoptosis in cells, respectively. Also was found cellular uptake of GQDs-[Fe-Salen] is higher than that of GQDs-[Fe-Salophen].

Synthesis, spectroscopic characterization, density functional theory, molecular docking studies, antioxidant and antimicrobial potential of novel Schiff base macrocyclic complexes of bivalent manganese

The threat of antibiotic resistance to public health is becoming a major cause of mortality on a worldwide scale. It has stimulated the interest of researchers in the development of novel antibiotics. Therefore, a new series of Schiff base macrocyclic ligands (N8MacL1‐N8MacL3) and their bivalent manganese complexes were synthesized and analyzed for biological activities. Characterization of the synthesized macrocyclic compounds was done by various spectroscopic techniques like elemental analysis, infrared (IR), proton nuclear magnetic resonance (NMR), 13C NMR, ultraviolet–visible, mass, electron paramagnetic resonance (EPR), and powder X‐ray diffraction (PXRD). Based on spectral studies, an octahedral environment has been proposed around the manganese metal center in the synthesized macrocyclic complexes. Density functional theory (DFT) calculations were used to evaluate the stability and the electronic properties of the synthesized macrocyclic ligands and their Mn (II) complexes. The structures of the synthesized compounds were optimized by using the def2‐SVP basis set at B3LYP level. The synthesized compounds were evaluated against gram‐positive bacterial strains (Staphylococcus aureus and Bacillus cereus), gram‐negative bacterial strains (Escherichia coli and Xanthomonas campestris), and fungal strains (Candida albicans and Fusarium oxysporum) for their antimicrobial activity by agar well diffusion method. Among all of the newly synthesized compounds, the macrocyclic complex [Mn(N8MacL3)Cl2] exhibited high antimicrobial activity against all bacterial and fungal strains except S. aureus. The virtual screening of synthesized Schiff base ligand [L], macrocyclic ligands (N8MacL1‐N8MacL3), and their Mn (II) complex [Mn(N8MacL1)Cl2‐Mn(N8MacL3)Cl2] are performed against the receptors, which were used for in vitro antimicrobial testing, to identify the most plausible drug–ligand interactions. The scavenging activity of DPPH radicals was utilized to study the antioxidant activity of the synthesized compounds. The macrocyclic metal complex [Mn(N8MacL3)Cl2] exhibited excellent antioxidant activity.

A study on the synthesis and characterization of Schiff base stabilized silver nanoparticles against propionic bacteria

Bacteriological contamination removing one of the most conservational problem in various environmental areas, predominantly in biomedical, effect of health care and disinfected applications. As synthesized optically transparent Schiff base stabilized silver nanoparticles (L-1AgNPs) of Schiff base ligand (N-(diphenylmethylene)-6-nitrobenzo[d]thiazol-2-amine) (L-1), has been successfully prepared, Schiff base stabilized silver nanoparticles were synthesized by easy process and straight forward protocol and using co-precipitation method. The synthesis of Schiff base stabilized silver nanoparticles using Schiff base ligand as a stabilizer. The synthesized Schiff base ligand (L-1) and its stabilized silver nanoparticles characterized were various spectroscopic technique, such as Fourier transform infrared (FT-IR), 1H NMR, Electron Spray Ionization (ESI) Mass, and UV–Visible spectroscopy, P-XRD and Transmission Electron Microscopy (TEM). AgNPs using as shows antibacterial activities of pathogenic gram positive bacteria like Propionic bacteria by using disc diffusion method. Here disc diffusion methods used for comparative studies and found inhibition zone on culture plate. The antimicrobial enhancing efficiency for Ag-nanopartics and diminished the pathogenic behaviour as conservational problem. Here comparatively L-1 is less antimicrobial activity with comparatively L-1-AgNPs showing 14 mm zone of inhibition effect. There is no inhibition zone of pure AgNO3. The microorganism for Propionic Bacteria against L-1-AgNPs show good activity as compared to L-1 and AgNO3.