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In the search for new therapeutic agents, a variety of diorganotin (IV) complexes were synthesized from Schiff base ligands (H2L1–H2L2) derived from 2‐amino‐4,6‐dichloro‐5‐methylphenol and 5‐nitrosalicylaldehyde/5‐chlorosalicylaldehyde. Structural characterization was performed using various analytical and physical techniques. Spectroscopic data confirmed that the ligands coordinate to the diorganotin (IV) ion via O‐ and N‐donor sites in an iminol configuration, indicating a pentacoordinated stereochemistry. TGA studies showed stability up to 120°C, and low conductance suggested nonelectrolytic nature. Bioactivity screening included the alamar blue assay for antituberculosis activity, serial dilutions for antimicrobial testing, and the bovine serum albumin technique for anti‐inflammatory evaluation. Notably, Complex 6 [Ph2SnL1] displayed the highest efficacy against tuberculosis (MIC: 0.0102 ± 0.0017 μmol/mL) and inflammation (IC50:7.9437 ± 0.02 μM) dysfunctions, which is comparable to standard drugs. Moreover, the metal complexes, particularly Complexes 6 and 10, exhibited the most promising antimicrobial activity with 0.0051–0.0052 μmol/mL MIC values. The efficacy pattern was Ph2SnL1–2 > Bu2SnL1–2 > Et2SnL1–2 > Me2SnL1–2. Evaluation of the ADMET profile elucidated the low toxicity levels and drug likeness properties of these compounds, highlighting their potential as promising therapeutic agents. [ABSTRACT FROM AUTHOR]

In the 21st century, pathogenic deformities contribute significantly to global morbidity and mortality. Our research investigates the antimalarial, antimicrobial, and antioxidant activities of newly synthesized hydrazones and their organotin (IV) complexes, derived from 2‐benzoyl‐1H‐indene‐1,3(2H)‐dione and 2‐phenoxypropanehydrazide/2‐(2,4‐dichlorophenoxy)propanehydrazide. Structural confirmation was achieved through multinuclear nuclear magnetic resonance (NMR), UV–Vis, IR, HRMS, thermogravimetric analysis (TGA), and scanning electron microscopy (SEM)‐energy‐dispersive X‐ray analysis (EDAX), revealing tridentate coordination of ligands to the tin metal via imine nitrogen and two enolic oxygens, forming a pentacoordinated geometry. The SEM analysis revealed that hydrazone ligand (1) exhibits a rectangular bar‐like microstructure, whereas its complex (5) shows a rugged surface with distinct territorial patches. Compounds (5) [Bu2SnL1] and (6) [Ph2SnL1] stood out with significant bioactivity, with antimalarial IC50 values ranging from 0.54 ± 0.07 to 0.67 ± 0.06 μM and antioxidant IC50 values from 4.39 ± 0.02 to 4.67 ± 0.01 μM. Additionally, compounds (6) [Ph2SnL1] and (10) [Ph2SnL4] exhibited the highest antimicrobial activity, with MIC values ranging from 0.0045 to 0.0042 μmol/mL, respectively, comparable to standard drugs. Complementing the experimental data, in silico molecular docking studies were performed on the most effective ligand (1) [H2L1] and its phenyl complex (6) [Ph2SnL1] with Plasmodium falciparum lactate dehydrogenase, revealing binding energies of −6.0 and −6.9 kcal/mol, respectively, and corroborating the experimental findings. Further, comprehensive absorption, distribution, metabolism, excretion, and toxicity (ADMET) evaluations were performed on each compound to gauge their suitability as drug candidates and potential for toxicity. [ABSTRACT FROM AUTHOR]

In recent times, there has been a growing exploration of transition metal complexes as potential solutions for significant health challenges, including tuberculosis, microbes infection, and inflammation. Therefore, in our ongoing effort to identify biologically effective agents, Co(II), Ni(II), Cu(II), and Zn(II) metal complexes of H2L1–H2L2 hydrazone ligands were synthesized. The structural features of synthesized compounds were recognized by employing several techniques such as FT‐IR, 1H NMR, 13C NMR, powder x‐ray diffraction (XRD), UV‐Vis, ESR, TG‐DTA, mass spectrometry, and molar conductance measurements. The bonding of ligands via Ophenolic, Oenolic, and Nazomethine donor atoms and the attachment of the three water molecules with metal ion to form the octahedral structure of complexes were corroborated by different spectroscopic techniques. The anti‐tuberculosis, antimicrobial, and anti‐inflammatory activities of the synthesized compounds were assessed using the microplate alamar blue assay, serial dilution, and bovine serum albumin (BSA) methods, respectively, and highlighted the more potency of the complexes than ligands. The synthesized Cu(II) (9) and Zn(II) (10) metal complexes exhibited excellent ability to inhibit the growth of H37Rv strain of Mycobacterium tuberculosis in comparison to standard drug streptomycin. The Cu(II) (6 and 9) and Zn(II) (10) complexes showed superb ability as antimicrobial agents, whereas Cu(II) (5) and Zn(II) (6) complexes exhibited significant anti‐inflammatory ability. The in vitro findings on the antituberculosis activity were reinforced by a significant molecular docking study, which has become a crucial component of computational research utilizing the enzyme Mtb Pks13 thioesterase domain of M. tuberculosis. Additionally, in this research work, the absorption–distribution–metabolism–excretion–toxicity (ADMET) study sparked the compounds' drug‐like behavior. [ABSTRACT FROM AUTHOR]

Malaria, a persistent and ancient adversary, continues to impact vast regions worldwide, afflicting millions and severely affecting human health and well‐being. Recently, despite significant progress in combating this parasitic disease, malaria remains a major global health concern, especially in areas with limited resources and vulnerable populations. Consequently, identifying and developing effective agents to combat malaria and its associated dysfunctions is essential therefore the two new Schiff base ligands incorporated Co(II), Ni(II), Cu(II) and Zn(II) ions were synthesized and thoroughly characterized. The synthesized compounds were assessed for in vitro anti‐malarial and antimicrobial efficacy, compounds (9, 10) demonstrated highest potential with IC50=1.08±0.09 to 1.18±0.04 μM against P. falciparum and MIC=0.0058 μmol/mL against C. albicans and E. coli, respectively. The complexes (5, 6) were effectively reduce mitigate oxidative stress with lowest IC50 value of 2.69±0.12 to 2.87±0.09 μM. Moreover, the biological findings were reinforced by a molecular docking investigation involving the potential compounds (2, 7–10) against dihydroorotate dehydrogenase and sterol 14‐alpha demethylase proteins which exposed complex's excellent biological response than their parent ligands. ADMET profiling was used to confirm the compounds' oral drug‐like features. This research offers promising prospects for future multi‐functional drug innovations targeting malaria, pathogenic infections, and oxidative stress. [ABSTRACT FROM AUTHOR]

Malaria caused by Plasmodium protozoa, transmitted by the Anopheles mosquitoes' is one ofthe most important diseases. Current antimalarial drugs target vital parasite progressions ormetabolic pathways essential for parasitic development, thus aiding the host in overcomingthe infection by inhibiting protozoa growth. However, at the same time, it also produces adisruptive consequence on the host cells. These cause severe adverse effects on the host andlead to drug resistance. The urgent need for novel, non‐toxic anti‐protozoal compounds isevident due to the resistance developed against drugs like chloroquine andhydroxychloroquine. Metal complexes of various elements like iron, gold, ruthenium, and othershave shown their anti‐malarial potential. We have reviewed the research ongoing globally on the developments of new molecules of chloroquine coupled with different transition elements and describe the structure–activity relationship of chloroquine, which also provides insights into the chemistry of these compounds. [ABSTRACT FROM AUTHOR]

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]

Our current efforts are aimed to synthesize 16 complexes of Co (II), Ni (II), Cu (II), and Zn (II) metal ions from heterocyclic hydrazone ligands by condensation reaction of 2,6‐diacetylpyridine with hydrazide derivatives to find out combating agent against microorganism diseases. The synthesized compounds were precisely characterized by various physicochemical and spectroscopic techniques like FT‐IR, UV–Vis, 1H and 13C NMR, magnetic susceptibility, ESR, mass spectrometry, powder XRD, TGA, and SEM that suggested the octahedral geometry of the complexes coordinating via enolic oxygen atoms, azomethine nitrogen atom, pyridine ring nitrogen atom of the hydrazone ligands, and oxygen atom of water molecule. The thermal stability of the complexes was demonstrated by thermal analysis revealing two‐step decompositions leaving behind metal oxide as an end residue. By using serial dilution method, the compounds (1–20) were tested for in vitro antimicrobial activity against four bacterial and two fungal pathogens. Among all the synthesized compounds, complex 16 was most active against B. subtilis, whereas complexes 13, 14, and 15 were most efficient for C. albicans. Moreover, the biological efficacy of H2L3(3) ligand and its (13–16) complexes were demonstrated by computational methods like molecular docking, MESP, DFT, and ADMET studies that highlight that complexes have more potency than the ligands and may be employed as effective drug for pathogen‐induced malformations. [ABSTRACT FROM AUTHOR]