Search

Infectious diseases have held a prominent place in the history of humanity, shaping societies, influencing medical advances, and affecting the lives of individuals on a global scale and are caused by a variety of pathogens that lead to a wide range of illnesses. Among this diverse group of ailments, tuberculosis (TB), inflammatory conditions, and various bacterial and fungal diseases stand out as major challenges that have long plagued humanity. Thus, the aim of this research is delve a significant combatting agent against TB, inflammation, bacterial and fungal deformities. To explore the above facts and to examine the therapeutic potential, the previously synthesized thiosemicarbazones (1–2) and their Co (II), Ni (II), Cu (II), Zn (II) complexes (3–10) of benzaldehydes and 4‐(4‐ethylphenyl)‐3‐thiosemicarbazide were proposed for in vitro investigation by microplate Alamar Blue, bovine serum albumin, and serial dilution methods. The compound (10) demonstrates almost double effectiveness in controlling TB dysfunction (minimum inhibitory concentration [MIC] value 0.006 ± 0.001 μmol/mL), surpassing streptomycin, whereas (6) and (9) have comparable TB inhibition efficacy to streptomycin. The compound (10) also has the highest potency for inflammation (6.75 ± 0.09 μM), bacterial (0.0066 μmol/mL), and fungal (0.0066 μmol/mL) ailments among the tested compounds with comparable inhibition abilities to their respective standard drugs. Moreover, molecular docking (targeting the PDB ID 6H53 and 1CX2 proteins), density functional theory (DFT), molecular electrostatic potential (MESP), and absorption, distribution, metabolism, excretion, and toxicity (ADMET) evaluations were performed against the highly efficient ligand (2) and its complexes (7–10) to validate the in vitro results. In this endeavor, our aim is to actively participate in the continuous initiatives aimed at fighting infectious diseases and enhancing global health and overall well‐being. [ABSTRACT FROM AUTHOR]

In this study, Schiff base ligand 1,1′‐((propane‐1,3‐diylbis [azaneylylidene]) bis (methaneylylidene))bis (naphthalen‐2‐ol) based Organyltellurium (IV) complexes were synthesized with formulae C32H27ClN2O3Te (5a)\C31H25ClN2O3Te (5b)\C32H27ClN2O3Te (5c)\ C39H34N2O4Te (5d)\ C37H30N2O4Te (5e)\ C39H34N2O4Te (5f) for acquiring a potential therapeutic agent. The synthesized compounds were characterized by ultraviolet–visible (UV–Vis), FT‐IR, 1H‐NMR, 13C‐NMR, mass spectrometry, molar conductance, elemental analysis, powder X‐ray diffraction and EDAX, which states that the tetradentate Schiff base ligand (HNDP) coordinated via oxygen and nitrogen atom with tellurium giving hexa‐coordinated tellurium (IV) complexes. The thermal features of the ligand and complexes were studied using thermal (TGA and DTG) technique. The biochemical behavior of the Schiff base and its complexes was assessed by examining their reactivity against various microbial strains, DPPH free radicals as well as normal and cancer cells. The complex 5c exhibited the highest inhibition activity against bacterial strains while complex 5f showed the strongest inhibition activity against fungal strains. Complexes 5e and 5f displayed the most effective suppression of DPPH free radicals. The results of in vitro cytotoxicity study revealed that complex 5a demonstrated moderate cytotoxic effect on the L929 cell lines. Complex 5c displayed a significant cytotoxic effect on the PC3 cell line. Moreover, complex 5a, 5c and 5e exhibited the best cytotoxic activity against the Saos‐2 cell line. Additionally, the structural forms of synthesized compounds were elucidated by DFT study. Furthermore, pharmacokinetic ADMET properties were estimated for their drug similarity behavior. The results advocate that complexes can be utilized as biological drugs. [ABSTRACT FROM AUTHOR]

In the search of novel and effective anti‐infectious agents, new hydrazone ligands (1–4) and their diorganotin (IV) complexes (5–20) were synthesized by condensing piperonylic hydrazide with salicylaldehyde derivatives, which have been further characterized by numerous physical and spectral techniques [1H, 13C, 119Sn] NMR, mass spectroscopy, UV–Vis, IR). These techniques ascertained dibasic tridentate coupling of hydrazone ligands with diorganotin (IV) through phenolic, enolic oxygens, and imine nitrogen, demonstrating pentacoordinated stereochemistry of the complexes. The thermal stability of up to 160°C of the complexes was ascertained by TGA studies whereas low conductance signified compounds have non‐electrolytic nature. Further, the antimicrobial activity was evaluated against four bacterial and two fungal strains by serial dilution assay, which demonstrated that the metal complexes (10, 11, 12) have comparable MIC values (0.0085–0.0098 μmol/ml) with ciprofloxacin and excellent biological responses in comparison of fluconazole. The phenyl complex [Ph2SnL2] (12) was found to be the most active antimicrobial agent with the lowest MIC value (0.0085 μmol/ml). The compounds were also screened for in vitro anti‐inflammatory activity by BSA denaturation assay and the phenyl complex [Ph2SnL2] (12) has been reported as most potent with 7.62 IC50 value, which is comparable with diclofenac sodium. Further, the biologically active complexes (9–12) and their hydrazone ligand [H2L2] were theoretically analyzed by computational investigations to support the in vitro results. The molecular docking analysis of compounds was performed on the active site of C. albicans (PDB ID: 5V5Z) and E. coli (PDB ID: 1HNJ) to assess the binding interactions and binding energy. The DFT and MESP (2, 9–12) revealed the most reactive areas, molecular geometry, Mulliken atomic charges, electronegativity, etc. of the compounds (2, 9–12). The ADMET profile showed the toxicity level and drug‐likeness properties, showing their potential to operate as viable antagonists. [ABSTRACT FROM AUTHOR]

Malaria, a relentless and ancient adversary, continues to cast its shadow over vast swathes of the globe, afflicting millions of people and have a heavy toll on human health and well-being. Despite substantial progress in the fight against this parasitic disease in recent decades, malaria still persists as a substantial global health concern, especially in some specific region which have limited resources and vulnerable populations. Thus, to ascertain an combating agent for malaria and its associated dysfunction, 4-(4-ethylphenyl)-3-thiosemicarbazide and benzaldehydes based two new thiosemicarbazone ligands (1–2) and their cobalt(II), nickel(II), copper(II), zinc(II) metal complexes (3–10) were synthesized in the present research work. The synthesized compounds were comprehensive characterized through spectral and physical investigations, demonstrating octahedral stereochemistry of the complexes. Further, the antimalarial and antioxidant potential of the compounds (1–10) were analyzed by micro assay and DPPH assay protocols, respectively, to examine the therapeutic aspect of the compounds. The performed biological evaluations revealed that the complexes are more efficient in controlling infectious ailment in comparison of ligands. The complexes (5), (6), (10) shows significant efficiency for malarial and oxidant dysfunctions whereas Zn(II) complex (6) exhibit highest potency with 1.02 ± 0.07 and 2.28 ± 0.05 µM IC50 value. Furthermore, to support the highest antimalarial potency of the (3–6) complexes and their associated ligand (1), the computational studies like molecular docking, DFT, MESP and ADMET analysis were executed which were supported the biological efficacy of the complex (6) by providing numerous parameters like binding interaction electronegativity, electrophilicity, HOMO value and electron density. [ABSTRACT FROM AUTHOR]

In the current research, we have reported the synthesis of eight new Co (II), Ni (II), Cu (II) and Zn (II) metal complexes from aldehyde derivatives and 3,5‐dichlorobenzohydrazide‐based hydrazone ligands (HL1HL2) in an effort to identify a combating agent for infectious ailments. Further, numerous physical and spectral studies were carried out to characterize the compounds and the spectral analysis indicates octahedral geometry around central metal ions in the complexes. The anti‐tuberculosis (TB) activity indicates that the complexes (3–10) are highly active for TB ailment and Zn (II) complex (10) has double efficacy to control the TB dysfunction with MIC value (0.006 ± 0.001 μmol/mL) in comparison with streptomycin (0.010 ± 0.001 μmol/mL) while complexes (6), (8), and (9) are comparably active (0.013 ± 0.001–0.014 ± 0.002 μmol/mL MIC) to inhibit the TB malformation. The antimicrobial investigation affirmed that zinc complex (10) has higher efficacy to control the microbial ailments with 0.0064–0.0129 μmol/mL MIC value. The anti‐inflammatory activity also revealed that the complexes (3–10) are highly active for inflammation and the Zn complex (10) has comparable IC50 value (7.58 ± 0.02 μM) with diclofenac sodium to hinder the inflammation diseases. Furthermore, the computational techniques such as molecular docking, density functional theory, molecular electrostatic potential and absorption, distribution, metabolism, excretion and toxicity studies were conducted against highly active ligand (2) and its complexes (7–10) which advocates that the biological activity of the hydrazone ligands was increased on complexation and the complex (10) has higher potency to control infectious ailments that behave as effective infection inhibitor without any toxic effects. Hence, the present research gives a new insight for in vivo investigation. [ABSTRACT FROM AUTHOR]

New diorganotin(IV) complexes (R2SnL, where R is Me, Et, Bu, and Ph) of Schiff base ligands N'-(2-hydroxybenzylidene)-3-methoxybenzohydrazide (H2L1), N'-(5-chloro-2-hydroxybenzylidene)-3-methoxybenzohydrazide (H2L2), N'-(2-hydroxy-5-nitrobenzylidene)-3-methoxybenzohydrazide (H2L3), and N'-(4-(diethylamino)-2-hydroxybenzylidene)-3-methoxybenzohydrazidefrom (H2L4) derived from 3-methoxybenzohydrazide with salicylaldehyde and its derivatives were synthesized. The ligands and their metal complexes were structurally characterized by spectroscopic techniques (FT-IR, 1H, 13C, and 119Sn NMR), elemental analysis, mass spectrometry, melting point, and molar conductance studies. The spectral data showed that ligands are coordinated to the tin atom in a tridentate manner with N and O donor sites of the azomethine-N, enolic-O, and aromatic hydroxyl-O to form a penta-coordinated geometry around central tin atom. The molar conductance data revealed that all compounds are non-electrolytes. In vitro antimicrobial activities of compounds were determined against various pathogens with reference to standard antibiotics which showed that compounds (12) (Ph2SnL2) and (16) (Ph2SnL3) are the most potent antimicrobial agents. Furthermore, the compounds were evaluated for antioxidant activity by using DPPH assay. The results obtained emphasized that the phenyl derivatives of complexes have enhanced antimicrobial and antioxidant activities as compared to other complexes. To check the drug-likeness, in silico studies of the synthesized compounds were carried out which described that all the compounds except (12) (Ph2SnL2), (19) (Bu2SnL4), and (20) (Ph2SnL4) can be used as orally active drugs. [ABSTRACT FROM AUTHOR]

The transition metal complexes of Co(II), Ni(II), Cu(II) and Zn(II) with bidentate Schiff base ligands (HL1−5) were obtained from condensation of 1, 2, 3, 4‐tetrahydro‐naphthalen‐1‐ylamine with methanolic solution of 3‐hydroxy‐salicylaldehyde, 4‐hydroxy‐salicylaldehyde, 5‐bromo‐salicylaldehyde, 3,5‐dibromo‐salicylaldehyde, and 2‐hydroxy‐1‐napthaldehyde. The synthesized compounds were structurally elucidated by spectral and physical methods. The spectral characterization emphasized bidentate nature (NO) of Schiff base ligands which gets chelated with metal via nitrogen atom of imine group and deprotonated oxygen of salicylaldehyde/2‐hydroxy‐1‐napthaldehyde group to form octahedral geometry around metal atom. Thermal results supported that the complexes are stable upto 200°C leaving metal oxide as an end products. The reported compounds (1–25) in this series were screened against the bacterial strains, that is, two Gram positive: Bacillus subtilis and Staphylococcus aureus, two Gram negative: Pseudomonas aeruginosa and Escherichia coli, and two fungal strains: Candida albicans andAspergillus niger and their results that indicated moderate to good activity with compounds 20 and 21 having good antimicrobial activity (minimum inhibitory concentration [MIC] value 0.0269–0.0067 μmol/ml) as compared with control drugs ciprofloxacine and fluconazole. Furthermore, cytotoxic studies of synthesized compounds were carried out against three human cancer cell lines: HCT‐116 (colon), A549 (alveolar), and MCF‐7 (breast) using standard drug paclitaxel. The results demonstrated that compounds 1 (IC50 values = 12.93, 15.13, 17.24), 3 (11.9, 9.29, 12.64), 9 (17.06, 20.06, 22.87), 14 (16.21, 18.47, 20.00), and 25 (17.54, 17.21, 20.23) for three cancer cell lines were found to be most potent candidates among the synthesized compounds. [ABSTRACT FROM AUTHOR]

A series of diorganotin(IV) complexes of type R2SnL, (where R = Me, Et, Bu and Ph) were prepared by the reaction of tridentate (NOO) donor Schiff base ligands with diorganotin(IV) dichloride in an equimolar ratio. The products were characterized by various spectroscopic techniques and physical and analytical methods (UV–vis, FTIR, NMR, fluorescence, elemental analysis). Spectroscopic data suggest that the Schiff base acts as a tridentate ligand (NOO) coordinated with a central tin atom via two oxygen and one imine nitrogen atom in a pentacoordinated fashion. The synthesized compounds were assayed for their in vitro antimicrobial activity against bacterial and fungal strains. All the compounds displayed promising results with the complexes being more potent than free ligands. The antioxidant activity of the compounds was determined by interaction with 2,2-diphenyl-1-picrylhydrazyl free radical. Complex Ph2SnL3 (16) was found to have the most potential antimicrobial activity against all tested strains and also exhibited excellent antioxidant activity. Quantitative structure–activity relationship of compounds was studied for antimicrobial activity with molar refractivity indices as significant statistical parameter. [ABSTRACT FROM AUTHOR]