Synthesis, characterization, X-ray structures, and biological activity of some metal complexes of the Schiff base 2,2′-(((azanediylbis(propane-3,1-diyl))bis(azanylylidene))bis(methanylylidene))diphenol

Synthesis, characterization, and biological activity of a fresh class of sonochemically synthesized Cu2+ complexes

The synthesis and characterization of metal complexes have garnered significant attention due to their versatile applications in scientific and biomedical fields. In this research, two novel copper (Cu) complexes, [Cu(L)(L')(H2O)2] (1) and [Cu(L)(Im)H2O] (2), where L = pyridine-2,6-dicarboxylic acid, L' = 2,4-diamino-6-hydroxypyrimidine, and Im = imidazole, were investigated concerning their sonochemical synthesis, spectroscopic analysis, and biological activity. The complexes' structural characterization was achieved using analytical techniques, including single-crystal X-ray structure determination, FTIR, PXRD, TGA and DTA, SEM, TEM, and EDS. Complex (1) displayed a six-coordinated Cu2+ ion, while complex (2) exhibited a five-coordinated Cu2+ ion. The crystal structures revealed monoclinic (C2/c) and triclinic (P-1) space groups, respectively. Both complexes showcased zero-dimensional (0D) supramolecular networks, primarily driven by hydrogen bonding and π-π stacking interactions, which played pivotal roles in stabilizing the structures and shaping the unique supramolecular architecture. Both complexes demonstrated significant antioxidant activity, suggesting their capability to neutralize free radicals and mitigate oxidative stress-related diseases. Hemolysis percentages were less than 2%, per the ASTM F756-00 standard, indicating non-hemolytic behavior. Low cytotoxicity was observed against fibroblast and MCF-7 cell lines. They do not exhibit antibacterial activity against Escherichia coli and Staphylococcus aureus. These findings suggest that the synthesized Cu2+‒complexes hold considerable promise for applications in drug delivery and cancer treatment. This research contributes to the advancement of supramolecular chemistry and the development of multifunctional materials for diverse scientific and medical applications.

Mixed-ligand complexes of copper(ii) with thienoyltrifluoroacetonate and nitrogen containing ligands: synthesis, structures, antimicrobial activity, cytotoxicity, Hirshfeld surface analysis and DFT studies

Mixed-ligand complexes of copper(ii) with thienoyltrifluoroacetonate (TTA-H), 2,2'-bipyridine (bipy), 1,10-phenanthroline (phen), and tetramethylethylenediamine (tmen), associated with counter ions such as Cl-, and NO3 - have been synthesized and characterized by molar conductance measurements, elemental analysis, mass spectrometry, IR and UV-Vis spectroscopy, antimicrobial activity, cytotoxicity assay studies, and single-crystal X-ray diffraction. The UV-Vis spectra and crystal structures are consistent with the adoption of square pyramidal geometry for all of the complexes except [Cu(TTA)tmen]NO3 and [Cu(TTA)2tmen] which have square planar and octahedral geometries, respectively. Conductance measurements of the mixed-ligand complexes indicated that they were all non-electrolytes, with the ligands and anions being coordinated to Cu except [Cu(TTA)tmen]NO3 which is a 1 : 1 electrolyte. All of the complexes were moderately active on all the fungi tested (Candida albicans, Aspergillus niger, Penicillium notatum, Rhizopus stolonifer) except [Cu(TTA)bipyCl] which showed increased activity in Candida albicans and Aspergillus niger. All of the compounds tested showed LC50 values greater than 100 with [Cu(TTA)(phen)NO3] being the least toxic of the compounds. Molecular geometries of the complexes were optimized at the PBE1PBE/def2SVP and PBE1PBE/6-311g(d,p) level of theory and the results were compared with the single-crystal X-ray diffraction data. Electronic properties such as HOMO, LUMO, HOMO-LUMO gaps and global reactivity descriptors are reported at the PBE1PBE/6-311g(d,p) level of theory. Hirshfeld surface analysis was carried out to investigate the cooperative non-covalent supramolecular interactions within the various complexes.

Synthesis, characterization, spectroscopic studies and biological evaluation of Schiff bases derived from 1-hydroxy-2-acetonapthanone

The four Schiff bases (I - IV) were synthesized by the condensation reaction of 1(1-hydroxynaphthalen-2-yl)ethanone, 1-(4-chloro-1hydroxynaphthalen-2-yl)ethanone and 1-(4-bromo-1-hydroxynaphthalen-2-yl)ethanone with propane-1,3-diamine and pentane-1,3-diamine. The structural analysis is done by UVvis., FT-IR, 1H NMR, 13C NMR, LCMS and elemental analyses. These compounds were assayed for antibacterial (Escherichia coli and Salmonella Typhi) activity and antioxidant (2,2-Diphenyl-1-Picryl Hydrazyl(DPPH) and Hydroxyl radical scavenging method) activity. The antibacterial and antioxidant activities of synthesized Schiff bases exhibited better degrees of inhibitory effects. Among these, Schiff base 2,2'-((propane-1,3-diylbis(azanylylidene))bis(ethan-1-yl-1-ylidene))bis(4-chloronaphthalen-1-ol) (II) exhibited excellent antibacterial activity with MICs of 0.12, 0.25, 0.5 and 1 mg/ml against E. coli and Salmonella Typhi. Furthermore, two Schiff bases such as, 2,2'-((propane-1,3-diylbis(azanylylidene))bis(ethan-1-yl-1-ylidene))bis(naphthalen-1-ol) (I) and 2,2'-((pentane-1,3-diylbis(azanylylidene))bis(ethan-1-yl-1-ylidene))bis(4-bromonaphthalen-1-ol) (IV) exhibited promising antioxidant activity.

The crystal structure of ethyl 4-((2-hydroxybenzyl)amino)benzoate, a Schiff base, C16H17NO3

C16H17NO3, triclinic, P1̅ (no. 2), a = 7.5445(7) Å, b = 8.3326(9) Å, c = 12.4291(10) Å, α = 94.468(8)°, β = 91.063(7)°, γ = 116.644(10)°, V = 695.01(13) Å3, Z = 2, R gt(F) = 0.0461, wR ref(F 2) = 0.1240, T = 291 K.

Coordination compounds of a hydrazone derivative with Co(iii), Ni(ii), Cu(ii) and Zn(ii): synthesis, characterization, reactivity assessment and biological evaluation

Increasing inhibitory effect of Zn-Hp2DAP < Hp2DAP < Co-Hp2DAP on ABC transporter MDR1 drug efflux pump.