Synthesis, structural, optical and anti-rheumatic activity of metal complexes derived from (E)-2-amino-N-(1-(2-aminophenyl)ethylidene)benzohydrazide (2-AAB) with Ru(III), Pd(II) and Zr(IV)

N'-(Furan-2-ylmethylene)-2-hydroxybenzohydrazide and its metal complexes: synthesis, spectroscopic investigations, DFT calculations and cytotoxicity profiling

The ligand, N'-(furan-2-ylmethylene)-2-hydroxybenzohydrazide (H2L), was synthesized characterized through various spectral studies which cleared out that the free ligand existed in keto form. The ligand upon reaction with Cu(II), Co(II), Ni(II) and Zn(II) acetates yielded complexes with stoichiometric ratio 1:2 (M:L) which has been validated through the elemental and mass spectral measurements. The IR and NMR spectral studies of the isolated complexes disclosed that the ligand chelated to metal ion in mononegative bidentate fashion via the azomethine nitrogen and deprotonated enolized carbonyl oxygen. Moreover, the DFT quantum chemical calculations designated that the ligand and Ni(II) complex exhibited the highest and lowest values of HOMO, LUMO energies and HOMO-LUMO energy gap, respectively. Furthermore, the in vitro cytotoxic activity towards HePG-2 and HCT-116 cell lines of the isolated compounds was investigated and the data cleared out that the ligand was more potent than the metal complexes.

Behavior of a Dynamic Covalent Library Driven by Combined Pd(II) and Biphasic Effectors for Metal Transport between Phases

This work reports the effect of Pd(II) as chemical effector on an acylhydrazone-based dynamic covalent library (DCL) in biphasic systems (water/chloroform). The constituents of the DCL are self-built and distributed in the two phases, two of them are lipophilic enough to play the role of a carrier agent that may transfer Pd(II) from the aqueous phase to the organic phase. Upon addition of Pd(II), the DCL of components exhibits a strong amplification of the constituent that is the most adapted to stabilize Pd(II) in chloroform as well as its agonist in water. This evolution is driven by the combination of the interaction of the DCL with Pd(II) and the presence of the two phases. This study paves the way to a novel approach for liquid/liquid extraction and metal recovery by means of adaptive extractant species generated in situ by a DCL.

Radiation synthesis and anticancer drug delivery of poly(acrylic acid/acrylamide) magnetite hydrogel

Hydrogels had gained considerable importance in drug delivery systems. Polyacrylic acid/acrylamide (AAc/AAm) and polyacrylic acid/acrylamide doped with magnetite (AAc/AAm)Fe3O4 hydrogels have been prepared by ɣ-radiations and characterized by Fourier transform infrared spectra (IR), X-ray diffractions (XRD), scanning electron microscope (SEM) and transmittance electron microscope (TEM). The morphology and the particle size were determined from TEM images. The average particle size of Fe3O4 was found to be 12 nm. The degree of cross-linking of Poly (AAc/AAm) hydrogel was determined from the gel fraction at different radiation doses and compositions. Swelling of the hydrogel was studied at different conditions. The magnetism of (AAc/AAm) Fe3O4 was studied by vibrating sample magnetometer and the results indicated super-paramagnetic character of (AAc/AAm)Fe3O4. The band gap (Eg) was determined and the values suggested semi-conductivity of the hydrogels. Doxorubicin loading and release by (AAc/AAm)Fe3O4 hydrogel was studied and indicated that the hydrogel can load 78% of doxorubicin.

Synthesis, spectral and extended spectrum beta-lactamase studies of transition metal tetraaza macrocyclic complexes

Urinary tract infections commonly occur in humans due to microbial pathogens invading the urinary tract, which can bring about a range of clinical symptoms and potentially fatal sequelae. The present study is aimed at addressing the development of a new antimicrobial agent against extended spectrum beta lactamase (ESBL) producing E. coli bacteria. We have synthesised some biologically potent (NNNN) donor macrocycles (L ₁  = dibenzo[f,n]dipyrido[3,4-b:4',3'-j][1,4,9,12]tetraazacyclohexadecine-6,11,18,23(5H,12H, 7H, 24H)-tetraone, and L ₂  = 6,12,19,25-tetraoxo-4,6,11,12,16,18,23,24-octahydrotetrabenzo [b,g,k,p][1,5,10,14]tetra azacyclooctadecine-2,13-dicarboxylic acid) and their Ti and Zr metal complexes in alcoholic media using microwave protocol. Macrocyclic ligands were synthesised by incorporating of 3,5-diaminobenzoic acid, phthalic acid and 3,4-diaminopyridine in 1:1:1 molar ratio. The macrocyclic ligands and their metal complexes have been characterised by elemental analysis, conductance measurement, magnetic measurement and their structure configurations have been determined by various spectroscopic (FTIR, ¹H/¹³C NMR, UV-Vis, LC-MS mass, XRD and TGA) techniques. [ZrL₂Cl₂]Cl₂ metal complex shows excellent antibacterial activity against ESBLs. A zone of inhibition and minimum inhibitory concentration was determined by McFarland and the dilution method, respectively. The spectral studies confirm the binding sites of the nitrogen atom of the macrocycles. An octahedral geometry has been assigned to the metal complexes based on the findings.