Thiophene-Derived Schiff Base Complexes: Synthesis, Characterization, Antimicrobial Properties, and Molecular Docking

Abstract

Novel thiophene-derived Schiff base ligand DE, where DE is (E)-N 1 ,N 1 -diethyl-N 2 -(thiophen-2-ylmethylene)ethane-1,2-diamine, and the corresponding M(II) complexes, [M(DE)X 2 ] (M = Cu or Zn, X = Cl; M = Cd, X = Br), were prepared and structurally characterized. X-ray diffraction studies revealed that the geometry around the center of the M(II) complexes, [Zn(DE)Cl 2 ] and [Cd(DE)Br 2 ], could be best described as a distorted tetrahedral. In vitro antimicrobial screening of DE and its corresponding M(II) complexes, [M(DE)X 2 ], was performed. The complexes were more potent and showed higher activities against Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa, fungi Candida albicans, and protozoa Leishmania major compared to the ligand. Among the studied complexes, [Cd(DE)Br 2 ] exhibited the most promising antimicrobial activity against all the tested microbes compared to its analogs. These results were further supported by molecular docking studies. We believe that these complexes may significantly contribute to the efficient designing of metal-derived agents to treat microbial infections.

An all-rounder aminoguanidine based ligand, its unusual anionic zinc(ii) and cadmium(ii) coordination complexes and their biological implications

“…The variations are influenced by the properties of the metal ions and may be coupled to the ligand framework and coordination, metal ion size, nature, etc. 37 Here, the same ligand, coordination framework, geometry and counter ion but with different metal ions are showing distinct antibacterial activities.…”

“…The spectra of the complexes 1 and 2 showed similar absorption features, but with slight shifts in λ max compared to that of the free ligand, signifying the coordination to the metal. 37 No d–d bands were observed for both the complexes and are attributed to the complete d 10 electronic configurations.…”

Theoretical and Experimental In‐vitro Studies of Novel Thiophene Based Organotellurium(IV) Complexes

“…The thiophene system and its derivatives [22][23][24] have attained prominent attention in material chemistry due to the presence of sulphur heteroatom which provides an alluring core frame-work for innumerable drugs to cure several contagious diseases. Nowadays, 2-thiophene carboxaldehyde is used in the industrial, [25][26][27][28] agricultural, [29] and medicinal fields because of its antibacterial, [30][31][32] antifungal, [33,34] antioxidant [35,36] and antitumor properties. [37,38] The metal complexes of tellurium [39] are significant due to their broad range of applications in biological processes.…”

Synthesis, XRD/HSA‐Interactions, QTAIM Analysis, Optical and Nonlinear Optical Responses Studies of Cu(II) Complex with the Schiff Base Ligand Derived from 5‐Bromosalicylaldehyde

“…[4][5][6][7] In recent investigations, a multitude of reports have elucidated that these ligands and their corresponding complexes can find applications in various fields, such as medicinal chemistry, biological systems, luminescent materials, and catalysis. [8][9][10][11][12] Indeed, the architecture of a coordinated metal complex is intricately shaped by a confluence of factors, including the metal's coordination abilities, the flexibility of ligands, and the propensity for interactions between ligands and metal ions. Notably, complexes of transition metals hold particular allure owing to their adaptability in geometric arrangements, a variety of coordination numbers, and a range of oxidation states.…”

“…Among the distinguished varieties of polydentate ligands, the Schiff base stands out prominently, commanding considerable interest among researchers for its adeptness in orchestrating coordination with metals through multiple binding sites [4–7] . In recent investigations, a multitude of reports have elucidated that these ligands and their corresponding complexes can find applications in various fields, such as medicinal chemistry, biological systems, luminescent materials, and catalysis [8–12] …”