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BackgroundHypoxia is a detrimental factor in solid tumors, leading to aggressiveness and therapy resistance. OMX, a tunable oxygen carrier from the heme nitric oxide/oxygen-binding (H-NOX) protein family, has the potential to reduce tumor hypoxia. [18F]Fluoromisonidazole ([18F]FMISO) positron emission tomography (PET) is the most widely used and investigated method for non-invasive imaging of tumor hypoxia. In this study, we used [18F]FMISO PET/CT (computed tomography) to assess the effect of OMX on tumor hypoxia in spontaneous canine tumors.ResultsThirteen canine patients with various tumors (n = 14) were randomly divided into blocks of two, with the treatment groups alternating between receiving intratumoral (IT) OMX injection (OMX IT group) and intravenous (IV) OMX injection (OMX IV group). Tumors were regarded as hypoxic if maximum tumor-to-muscle ratio (TMRmax) was greater than 1.4. In addition, hypoxic volume (HV) was defined as the region with tumor-to-muscle ratio greater than 1.4 on [18F]FMISO PET images. Hypoxia was detected in 6/7 tumors in the OMX IT group and 5/7 tumors in the OMX IV injection group. Although there was no significant difference in baseline hypoxia between the OMX IT and IV groups, the two groups showed different responses to OMX. In the OMX IV group, hypoxic tumors (n = 5) exhibited significant reductions in tumor hypoxia, as indicated by decreased TMRmax and HV in [18F]FMISO PET imaging after treatment. In contrast, hypoxic tumors in the OMX IT group (n = 6) displayed a significant increase in [18F]FMISO uptake and variable changes in TMRmax and HV.Conclusions[18F]FMISO PET/CT imaging presents a promising non-invasive procedure for monitoring tumor hypoxia and assessing the efficacy of hypoxia-modulating therapies in canine patients. OMX has shown promising outcomes in reducing tumor hypoxia, especially when administered intravenously, as evident from reductions in both TMRmax and HV in [18F]FMISO PET imaging.

New isatin-thiosemicarbazone (1–6) were obtained from various 5-methylisatin and various isothiocyanates with good yields and efficient methods. The structures of the synthesized compounds were clarified by FT-IR, 1H-NMR, and 13C-NMR spectroscopic techniques and elemental analysis. The antioxidant activity properties of the compounds were investigated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging method and total reducing power determinations. In our total reducing power study, where we chose Trolox as the standard antioxidant, it was found that the reducing powers of compounds containing different substituent groups and positions were close to each other and lower than Trolox. In the study using butylated hydroxytoluene (BHT) as a reference antioxidant, DPPH antiradical scavenging capacities of the synthesized compounds were determined. The free radical scavenging effects of the synthesized compounds were compared with the IC50 values obtained from the concentration equations and were found in the order BHT > 6 > 3 > 5 > 1 > 2 > 4. Structural and electronic properties of the compounds were examined by density functional theory (DFT) calculations and their relationship with the antioxidant properties of the compounds was discussed. DFT calculations played an important role in determining how the electronic properties of the synthesized compounds, especially in the presence of different substituents and in the ortho and meta positions, and accordingly the antioxidant properties of the compounds, changed. Experimental and theoretical results confirmed that methoxy-containing structures in the synthesized compounds exhibit higher antioxidant effects compared to halogen-containing structures, regardless of their position. [ABSTRACT FROM AUTHOR]

ABSTRACT Tin complexes, Sn(IV)‐TSC 1·MeOH and Sn(IV)‐TSC 2, with thiosemicarbazones possessing an N2S ligation system [TSC 1 = 4‐(4‐nitrophenyl)‐1‐((pyridin‐2‐yl)methylene)thiosemicarbazide and TSC 2 = 4‐(2‐methoxyphenyl)‐1‐((pyridin‐2‐yl)methylene)thiosemicarbazide] were prepared and structurally characterized. These complexes are found in the space groups P1¯$$ \overline{1} $$ and P21/n, respectively, with their tin atoms in octahedral environments established by three chlorine atoms and an anionic thiosemicarbazone ligand. All compounds (20 mg/mL in DMSO) were tested for their antibacterial [against Bacillus subtilis, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa] and antifungal [against Aspergillus flavus and Candida albicans] properties. The ligand TSC 2 displayed inhibitions in the S. aureus and E. coli cultures (with zones of 11 and 10 mm, respectively), whereas Sn(IV)‐TSC 1·MeOH and Sn(IV)‐TSC 2 inhibited all bacteria with 11–15 and 14–16 mm, respectively. In the fungal cultures, only Sn(IV)‐TSC 1·MeOH (10 mm) showed an inhibition zone against A. flavus. The ligands' antiproliferative activities were determined against human cancer cells of the lung, breast, liver, and colon, and both ligands afforded the highest activity against the breast MCF‐7 cells. The complexation enhanced the ligands' activities as TSC 1, TSC 2, Sn(IV)‐TSC 1·MeOH, and Sn(IV)‐TSC 2 afforded respective IC50 values of 52.4, 153.7, 18.3, and 63.9 μM. However, against normal baby hamster kidney (BHK) cells, these compounds showed IC50 data of 54.8, 82.7, 16.1, and 15.3 μM, respectively. [ABSTRACT FROM AUTHOR]

In this study, we present a simple method for preparing a new series of thiazoles with excellent isolated yields. To synthesize the target thiazole scaffolds, a straightforward one‐pot procedure was developed including an amine‐mediated reaction of isoxazolethiazolidin‐4‐one derivative, thiosemicarbazide, and appropriate hydrazonyl chlorides. The reaction conditions for this one‐pot protocol were optimized by experimenting with different solvents and amines. The best results were achieved by conducting the reaction in dioxane with triethylamine at 100°C for 5 h. The structures of the desired products were proved by different elemental analyses and spectral data. Additionally, the antimicrobial efficacy of all target derivatives was assessed against various types of microorganisms. The results observed indicated that the antimicrobial activity of the thiosemicarbazone derivative 2 was the strongest activity among the new series, with MIC values ranging from 0.03 ± 0.01 to 0.98 ± 0.15 μg/mL. Moreover, antioxidant evaluations were conducted on all the desired targets, using ascorbic acid as a reference drug. Significantly, derivatives 2 and 10 demonstrated the most promising antioxidant inhibitory effects. Additionally, further toxicity studies were performed on the most active novel compounds, revealing their best drug‐like properties and varying toxicity risks in humans. [ABSTRACT FROM AUTHOR]

A novel (E)-1-(4-methylbenzylidene)-4-(3-isopropylphenyl) thiosemicarbazone was synthesized in a one-pot four-step synthetic route. Fourier transform infrared spectroscopy (FTIR), 1H and 13C nuclear magnetic resonances (NMR), single-crystal X-ray diffraction, and UV-visible absorption spectroscopy were utilized to confirm the successful preparation of the title compound. Single-crystal data indicated that the intramolecular hydrogen bond N(3)-H(3)···N(1) and intermolecular hydrogen bond N(2)-H(2)···S(1) (1 − x, 1 − y, 1 − z) existed in the crystal structure and packing of the title compound. Besides the covalent interaction, the non-covalent weak intramolecular hydrogen bond N(3)-H(3)···N(1) discussed by atoms in molecules (AIM) theory also functioned in maintaining the title compound's crystal structure. The strong intermolecular hydrogen bond N(2)-H(2)···S(1) (1 − x, 1 − y, 1 − z) discussed by Hirshfeld surface analysis played a major role in maintaining the title compound's crystal packing. The local maximum and minimum electrostatic potential of the title compound was predicted by electrostatic potential (ESP) analysis. The UV-visible spectra and HOMO-LUMO analysis revealed that the title compound has a low ΔEHOMO–LUMO energy gap (3.86 eV), which implied its high chemical reactivity due to the easy occurrence of charge transfer interactions within the molecule. Molecular docking and in vitro antifungal assays evidenced that its antifungal activity is comparable to the reported pyrimethanil, indicating its usage as a potential candidate for future antifungal drugs. [ABSTRACT FROM AUTHOR]

The antiproliferative and antibacterial activities of thiosemicarbazones increase markedly with the presence of metal ions. One of the factors determining the activity of metal thiosemicarbazone complexes is the coordination structure. In this study, the biological effects of new antimony (III) and bismuth (III) thiosemicarbazone complexes with different binding modes and geometrical structures were demonstrated. Three new complexes, with the formulae {[SbCl3(µ2-S-Hacptsc)(η1-S-Hacptsc)], 2/3H2O,1/3CH2Cl2}, {[SbCl3(κ2-S,N-Hacpmtsc)(η1-S-Hacpmtsc)2CH2Cl2]}, and{[BiCl3(η1-S-Hbzmtsc)3]·C2H5OH}, where Hacptsc: acetophenone thiosemicarbazone, Hacpmtsc: acetophenone-N-methyl thiosemicarbazone, Hbzmtsc: benzaldehyde-N-methyl thiosemicarbazone) were elucidated by different methods and deeply analyzed in accordance with their structure by X-ray structure analysis and Atoms-In-Molecules topological analysis. This analysis provided a deeper understanding of the coordination spheres of the Sb/Bi complexes. For instance, the first reported two binding modes of the same ligand are observed in a single crystal structure of antimony (III) halide complexes. Additionally, in one of the complexes, a solid-to-solid phase transition was detected and analyzed in detail. Those complexes, very unique in terms of their geometry, have also been tested for their in vitro cytotoxic activity against human adenocarcinoma cervical cancer (HeLa) cells, whereas antimony (III) complex 1is the most active complex of this study. Further, the antibacterial activity of the complexes has been screened against two Gram-negative (Pseudomonas aeruginosa and Escherichia coli) and two Gram-positive (Staphylococcus epidermidis and Staphylococcus aureus) pathogenic bacteria. From the results, it is found that all the complexes exhibited significant activity against the Gram-negative pathogenic bacteria. [ABSTRACT FROM AUTHOR]

Iron plays a crucial role in various metabolic processes. However, the impact of 5-aminolevulinic acid (ALA) in combination with iron chelators on iron metabolism and the efficacy of ALA-photodynamic therapy (PDT) remain inadequately understood. This study aimed to examine the effect of thiosemicarbazone derivatives during ALA treatment on specific genes related to iron metabolism, with a particular emphasis on mitochondrial iron metabolism genes. In our study, we observed differences depending on the cell line studied. For the HCT116 and MCF-7 cell lines, in most cases, the decrease in the expression of selected targets correlated with the increase in protoporphyrin IX (PPIX) concentration and the observed photodynamic effect, aligning with existing literature data. The Hs683 cell line showed a different gene expression pattern, previously not described in the literature. In this study, we collected an extensive analysis of the gene variation occurring after the application of novel thiosemicarbazone derivatives and presented versatile and effective compounds with great potential for use in ALA-PDT. [ABSTRACT FROM AUTHOR]

Heterocyclic systems containing 2-(2-hydrazinyl) thiazole moieties were synthesized by heterocyclization of thiosemicarbazones with arylglyoxals and Meldrum's acid in ethanol and water 1:1 (v/v) under reflux conditions. The paper reports an efficient, facile, and environmentally friendly protocol via a novel one-pot three-component reaction to access a broad range of 2-(2-Hydrazinyl) thiazole derivatives. Products were isolated by plate chromatography and their structures were established from their spectroscopic data, then the antibacterial and antioxidant activity of synthesized 2-(2-hydrazinyl) thiazole derivatives were evaluated, and demonstrated encouraging antibacterial activity against Staphylococcus aureus as a gram positive bacteria and Escherichia coli as a gram negative bacteria. Furthermore, when representative products were assessed for radical scavenging activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH0), high antioxidant effects were observed, indicating their potential safety for use in pharmacological studies. [ABSTRACT FROM AUTHOR]

Dihydrofolate reductase (DHFR), an essential enzyme in folate metabolism, presents a promising target for drug development against various diseases, including cancer and tuberculosis. Herein, we present an integrated approach combining in vitro biochemical assays with in silico molecular docking analysis to evaluate the inhibitory potential of 4-piperidine-based thiosemicarbazones 5(a-s) against DHFR. In our in vitro study, a novel series of 4-piperidine-based thiosemicarbazones 5(a-s) were assessed for their inhibitory activity against DHFR enzyme. The synthesized compounds 5(a-s) exhibited potent inhibition with IC50 values in the range of 13.70 ± 0.25 µM to 47.30 ± 0.86 µM. Among all the derivatives 5p displayed highest inhibitory activity. Simultaneously, in silico analysis were performed and compared with standard drug (Methotrexate) to predict the binding affinity and interaction pattern of synthesized compounds with DHFR active site. SAR analysis was done to elucidate how structural modifications impact compound’s biological activity, guiding the rational design of potent and selective drug candidates for targeted diseases. These findings may provide a comprehensive assessment of 4-piperdine-based thiosemicarbazones as DHFR inhibitors and contribute to the development of novel therapeutics targeting DHFR-associated diseases. [ABSTRACT FROM AUTHOR]

In this investigation, the bio‐activity and biosafe potential of thiosemicarbazonates of nickel(II) as well as that of ligands are described. Reactions of nickel(II) acetate with a series of thiosemicarbazones, {R1(py)C2=N3‐N2(H)‐C1(=S)‐NHR; R1=py, Me, H and Ph; R=H, Me, Et, Ph}, led to the loss of acidic hydrazinic N2(H) protons, and resulted in the formation of six‐coordinated complexes of stoichiometry, [Ni(N,N,S−L)2], where anionic N,N,S−L=py2tsc‐NHR, 1–4; apytsc‐NHR, 5–8; pytsc‐NHR, 9–12 and bpytsc‐NHR, 13–16. All these complexes have been characterized using analytical data, IR and UV‐visible spectroscopy and ESI‐mass spectrometry. The single crystal X‐ray crystal structure of several complexes {2(Me), 7(Et), 11(Et), 12(Ph), 13(H),14(Me) and 15(Et)} were also determined. Thio‐ligands coordinate to nickel(II) through pyridyl nitrogen‐N4, azomethine nitrogen‐N3 and thiolato sulfur atoms, resulting in the formation of homoleptic complexes with octahedral structures. Complexes 1–16 and uncoordinated thiosemicarbzones, were evaluated for their antimicrobial activity, in terms of ZOI, MIC, time kill assay and in vitro percent cell viability MTT assay, against clinical isolate methicillin‐resistant Staphylococcus aureus (MRSA), Staphylococcus aureus (MTCC740), Klebsiella pneumonia (MTCC109), Salmonella typhimurium (MTCC1251), and Candida albicans (MTCC227), a yeast. Both the ligands and their metal complexes exhibited moderate to high bioactivity, and were found to be biosafe with high cell viability, 88–92 %, in several cases. [ABSTRACT FROM AUTHOR]

Nickel transition metal complexes have shown various biological activities that depend on the ligands and geometry. In this contribution, six Ni(II) nitrate complexes with pyridoxal-semi, thiosemi, and isothiosemicarbazone ligands were examined using theoretical chemistry methods. The structures of three previously reported complexes ([Ni(PLSC)(H2O)3]∙2NO3−, [Ni(PLTSC)2] ∙2NO3−∙H2O, and [Ni(PLITSC)(H2O)3]∙2NO3−) were investigated based on Hirshfeld surface analysis, and the most important stabilization interactions in the crystal structures were outlined. These structures were optimized at the B3LYP/6-311++G(d,p)(H,C,N,O,(S))/LanL2DZ(Ni) level of theory, and the applicability was checked by comparing theoretical and experimental bond lengths and angles. The same level of theory was applied for the optimization of three additional structures, ([Ni(PLSC)2]2+, [Ni(PLTSC)(H2O)3]2+, and [Ni(PLITSC)2]2+). The interactions between selected ligands and Ni(II) were examined using the Natural Bond Orbital (NBO) and Quantum Theory of Atoms in Molecules (QTAIM) approaches. Particular emphasis was placed on interactions between oxygen, sulfur, and nitrogen donor atoms and Ni(II). Human Serum Albumin (HSA) and the DNA-binding properties of these complex cations were assessed using molecular docking simulations. The presence of water molecules and various substituents in the thermodynamics of the processes was demonstrated. The results showed significant effects of structural parameters on the stability and reactivity towards important biomolecules. [ABSTRACT FROM AUTHOR]

Tyrosinase, a key enzyme in melanin synthesis, represents a crucial therapeutic target for hyperpigmentation disorders due to excessive melanin production. This study aimed to design and evaluate a series of indole–thiourea derivatives by conjugating thiosemicarbazones with strong tyrosinase inhibitory activity to indole. Among these derivatives, compound 4b demonstrated tyrosinase inhibitory activity with an IC50 of 5.9 ± 2.47 μM, outperforming kojic acid (IC50 = 16.4 ± 3.53 μM). Kinetic studies using Lineweaver–Burk plots confirmed competitive inhibition by compound 4b. Its favorable ADMET and drug-likeness properties make compound 4b a promising therapeutic candidate with a reduced risk of toxicity. Molecular docking revealed that the compounds bind strongly to mushroom tyrosinase (mTYR) and human tyrosinase-related protein 1 (TYRP1), with compound 4b showing superior binding energies of −7.0 kcal/mol (mTYR) and −6.5 kcal/mol (TYRP1), surpassing both kojic acid and tropolone. Molecular dynamics simulations demonstrated the stability of the mTYR−4b complex with low RMSD and RMSF and consistent Rg and SASA values. Persistent strong hydrogen bonds with mTYR, along with favorable Gibbs free energy and MM/PBSA calculations (−19.37 kcal/mol), further support stable protein–ligand interactions. Overall, compound 4b demonstrated strong tyrosinase inhibition and favorable pharmacokinetics, highlighting its potential for treating pigmentary disorders. [ABSTRACT FROM AUTHOR]

The electrochemical oxidation of anodic metals (M = nickel and palladium) in an acetonitrile solution of the thiosemicarbazone ligands (E)-2-(1-(4-methoxyphenyl)ethylidene)-N-methylhydrazine-1-carbothioamide (a), (E)-2-(1-(p-tolyl)ethylidene)hydrazine-1-carbothioamide (b), and (E)-N-phenyl-2-(1-(p-tolyl)ethylidene)hydrazine-1-carbothioamide (c) yielded the homoleptic complexes [ML2], 1a, 1b, 1c, and 2c and [M4L4], 2a as air-stable solids. The crystal structures for 1a, 1b, 1c, and 2c show the ligands in a transoid disposition with the [S,S] and [N,N] donor atom pairs occupying cis positions on the nearly square planar coordination plane of the metal. The structure for 2a of S4 symmetry comprises a tetranuclear palladacycle where the metalated ligands are arranged around a central Pd4S4 environment: a crown ring with alternating palladium and sulfur atoms. The latter complex is the first example of an electrochemical preparation of a cyclometalated palladium compound, marking a milestone in the chemistry of such species. The compounds have been fully characterized by elemental microanalysis, mass spectrometry, infrared (IR), and 1H nuclear magnetic resonance (NMR) spectra. [ABSTRACT FROM AUTHOR]

Two complexes of Sn (IV), Sn (IV)‐TSC 1 and Sn (IV)‐TSC 2, with the ligands 4‐(2,4‐dimethylphenyl)‐1‐([pyridin‐2‐yl]methylene)thiosemicarbazide (TSC 1) and 4‐(2,5‐dimethoxyphenyl)‐1‐([pyridin‐2‐yl]methylene)thiosemicarbazide (TSC 2) were synthesized. X‐ray crystallographic investigation of Sn (IV)‐TSC 2 afforded valuable information on its octahedral geometry, monoclinic lattice and C 1 2/c 1 space group. The ligands are monoanionic tridentate via a deprotonated thiol sulfur atom and two nitrogen atoms of pyridine and azomethine moieties. These atoms coordinate tin alongside three independent chlorine atoms making the tin atoms in the complexes tetravalent, despite of incorporating tin (II) chloride in the reactions. Solutions of the ligands TSC 1 and TSC 2 (20 mg/ml in dimethyl sulfoxide) induced growth inhibitions only to Staphylococcus aureus (14 and 10 mm) and Escherichia coli (15 and 10 mm) bacteria. But the complexes displayed activities against four bacterial species, that is, S. aureus, E. coli, Bacillus subtilis and Pseudomonas aeruginosa (complex Sn (IV)‐TSC 1, complex Sn (IV)‐TSC 2 and ampicillin showed inhibition diameters with 12–14, 13–14 and 21–26 mm). All TSC ligands and coordination compounds induced cytotoxicity in MCF‐7 cancer and BHK normal cells. The compounds TSC 1, TSC 2, Sn (IV)‐TSC 1, Sn (IV)‐TSC 2 and doxorubicin inhibited the MCF‐7 (BHK) cells with IC50 values of 68.9 (126.6), 145.4 (110.6), 22.6 (16.7), 34.2 (16.1) and 9.66 (36.42) μM, respectively. [ABSTRACT FROM AUTHOR]

Abstract Dihydrofolate reductase (DHFR), an essential enzyme in folate metabolism, presents a promising target for drug development against various diseases, including cancer and tuberculosis. Herein, we present an integrated approach combining in vitro biochemical assays with in silico molecular docking analysis to evaluate the inhibitory potential of 4-piperidine-based thiosemicarbazones 5(a-s) against DHFR. In our in vitro study, a novel series of 4-piperidine-based thiosemicarbazones 5(a-s) were assessed for their inhibitory activity against DHFR enzyme. The synthesized compounds 5(a-s) exhibited potent inhibition with IC50 values in the range of 13.70 ± 0.25 µM to 47.30 ± 0.86 µM. Among all the derivatives 5p displayed highest inhibitory activity. Simultaneously, in silico analysis were performed and compared with standard drug (Methotrexate) to predict the binding affinity and interaction pattern of synthesized compounds with DHFR active site. SAR analysis was done to elucidate how structural modifications impact compound’s biological activity, guiding the rational design of potent and selective drug candidates for targeted diseases. These findings may provide a comprehensive assessment of 4-piperdine-based thiosemicarbazones as DHFR inhibitors and contribute to the development of novel therapeutics targeting DHFR-associated diseases.

Nine potentially bidentate thiosemicarbazone (HLn) ligands and their tricarbonylrhenium(I) complexes, [ReY(HLn)(CO)3] (Y=Cl, Br), were synthesized and their binding affinity towards the alpha and beta receptors were determined using a competitive standard radiometric assay with [3H]‐estradiol. Even in the absence of a base, coordinated thiosemicarbazones can undergo deprotonation causing the release of the coordinated halide forming dimeric species, [Re2(Ln)2(CO)6]. The observation of the formation of the dinuclear complex where the thiosemicarbazone ligand adopts the zwitterionic form, [Re2(HL9)2(CO)6]Br2, motivated the theoretical study of the relative stability of these species. Despite the ease of formation of the dimer complexes, it was possible to optimize a synthetic route to obtain the [2+1] complexes [Re(Ln)(pym)(CO)3] where pym is the monodentate ligand 4‐dimethylamino‐pyridine or 4‐hydroxy ‐pyridine. The inclusion of this additional ligand substantially improves the affinity against the receptors (in some cases against both). [99mTc(Ln)(pym)(CO)3] complexes were also prepared using [99mTc(H2O)(CO)3]+, an excess of HLn ligand and in the presence of pym. The radiochromatograms show the formation of the [2+1] complex but also the presence of species resulting from the substitution of pym by chloride and water. However, the ratio of intensities between the three signals remains constant with the variation of the relative concentration of the three monodentate ligands suggesting an equilibrium between the three complexes. [ABSTRACT FROM AUTHOR]

To investigate the coordination chemistry of the complexes formed by aromatic thiosemicarbazones with main group elements, a number of complexes of benzaldehyde-derived thiosemicarbazone ligands with antimony(III) halides were synthesized. Three new complexes were prepared by the reaction of thiosemicarbazones with antimony(III) halides in 2 : 1 molar stoichiometric ratios. The molecular structures of these complexes were revealed using spectroscopic methods. The stoichiometric ratio in the complexes was determined by the elemental analysis method. By using FT-IR, FT-Raman and 1H and 13C NMR spectroscopy methods, it was observed that thiosemicarbazones were bound in the thione form and η1-S coordination type and µ2-Cl bridging bond in all complexes. Thermal stability and degradation steps due to heating were examined by thermogravimetric differential thermal analysis method (TG-DTA). [ABSTRACT FROM AUTHOR]

One of the most serious future challenges to health care professionals is the emergence of multi-drug resistance pathogenic microbes that rapidly develop resistance to currently used antibiotics. So, as a way to overcome the antimicrobial drug-resistance problems, it is urgent need to synthesize several new lead molecules that are expected to have antibacterial and antifungal activities. So, some new thiazolidinone and methylthiazole derivatives incorporating benzodioxole nucleolus were constructed. Two different series of N-substituted thiosemicarbazones carrying a benzodioxole nucleus were synthesized through mutation reaction of the different aromatic and heterocyclic aldehydes with benzodioxolyl thiosemicarbazide. Cycloalkylation reaction of the latter thiosemicarbazones through with both of the ethyl chloroacetate or chloroacetone gave the thiazolidin-4-ones or 4-methylthiazoles, respectively. The antimicrobial activity of the thiazolidin-4-one and 4-methylthiazole derivatives was investigated. All of compounds showed from weak to moderate effects toward all tested bacteria. [ABSTRACT FROM AUTHOR]

Thiosemicarbazones (TSCs) with their modular character (thiosemicarbazides + carbonyl compound) allow broad variation of up to four substituents on the main R1R2C=N(1)–NH–C(S)–N(4)R3R4 core and are thus interesting tools for the formation of conjugates or the functionalization of nanoparticles (NPs). In this work, di-2-pyridyl ketone was introduced for the coordination of metals and 9-anthraldehyde for luminescence as R1 and R2 to TSCs. R3 and R4 substituents were varied for the formation of conjugates. Amino acids were introduced at the N4 position to produce [R1R2TSC–spacer–amino acid] conjugates. Further, functions such as phosphonic acid (R–P(O)(OH)2), D-glucose, o-hydroquinone, OH, and thiol (SH) were introduced at the N4 position producing [R1R2TSC–spacer–anchor group] conjugates for direct NP anchoring. Phenyl, cyclohexyl, benzyl, ethyl and methyl were used as spacer units. Both phenyl phosphonic acid TSC derivatives were bound on TiO2 NPs as a first example of direct NP anchoring. [R1R2TSC–spacer–end group] conjugates including OH, S–Bn (Bn = benzyl), NH–Boc (Boc = tert-butyloxycarbonyl), COOtBu, C≡CH, or N3 end groups were synthesized for potential covalent binding to functional molecules or functionalized NPs through amide, ester, or triazole functions. The synthesis of the thiosemicarbazides H2NNH–C(S)–NR3R4 starting from amines, including amino acids, SCCl2 or CS2, and hydrazine and their condensation with dipyridyl ketone and anthraldehyde led to 34 new TSC derivatives. They were synthesized in up to six steps with overall yields ranging from 10 to 85% and were characterized by a combination of nuclear magnetic resonance spectroscopy and mass spectrometry. UV-vis absorption and photoluminescence spectroscopy allowed us to easily trace the dipyridyl imine and anthracene chromophores. [ABSTRACT FROM AUTHOR]

This study focuses on the synthesis of azo‐thiosemicarbazone ligand, which is designed by reacting 2‐hydroxy‐5‐(phenyldiazenyl)benzaldehyde with hydrazine carbothioamide. Hence, this ligand was exploited for chelation with nickel and cupric salts in (1 M:1 L) molar ratio. These synthetics were structurally investigated using a variety of physical, analytical, and spectroscopic (1D/2D‐NMR, UV–Vis, FT‐IR, and E‐mass) tools as well as theoretically. The finding demonstrated that the resulting azo‐thiosemicarbazone (H4Azo‐TSC) bonded with the nickel and cupric ions as mono/di‐basic tridentate chelators, binding them via deprotonated phenolic oxygen, imino nitrogen, and thionic/thiol sulfur atoms adopting square planar geometry. The theoretical investigation was examined by DFT/B3LYP/LanL2dZ, including energetic parameters, HOMO‐LUMO energy gap, dipole moment, and geometrical optimization, which were applied to support the complexes' geometrical structure. The in vitro microbicidal activities of the azo‐thiosemicarbazone, compared with its Ni2+ and Cu2+ complexes, display superior activity over the metal complexes against different bacterial and fungal species. The anticancer efficacy of the synthetics was tested against human lung fibroblast (WI38) and mammary gland breast cancer (MCF‐7) compared with Doxorubicin as a standard drug. The cytotoxic efficiency of metallic complexes exceeded that of un‐chelated azo‐thiosemicarbazone. The most effective complex is Ni2+ complex with IC50 equal to 11.75 and 14.05 μg/ml, respectively. It has been demonstrated that Ni2+ and Cu2+ complexes are more biocompatible than free azo‐thiosemicarbazone; this finding may be related to the chelation process. [ABSTRACT FROM AUTHOR]

Purpose: Prostate cancer afflicts thousands of men around the world. This condition is the most common in men among all cancer diagnoses, and it ranks second in terms of fatality after lung cancer. Six out of ten males in the 65-year-old age group have been diagnosed with prostate cancer, making it a common malignancy among this age group and accounting for about 80% of all reported instances of prostate cancer. Method: Quantitative structure-activity relationship (QSAR) techniques was utilized to construct five models on (24) prostate cancer PC3 cell line therapeutic agents. Result: Among the five models built, model one was the best because of its statistical fitness of (R²) = 0.9882, (R² adj) = 0.9828, (SEE) = 0.0488, (MEA) = 0.0258 and (CCC) = 0.9235 and based on docking results, the top ranking compounds with high docking scores at the range of (-7.7 to -8.2kcal/mol) respectively. Furthermore, none of the top ranking compounds was found to violate any of the five filters in the study, therefore, displaying good pharmacokinetics and drug- likeness properties. Conclusion: Three top ranking compounds were identified using molecular docking virtual screening and compound 12 was recognized to have the most excellent docking score of (-8.2 kcal/mol). Also, the most common type of interaction among the chosen ligands is hydrogen bond interaction, electrostatic and hydrophobic interaction. [ABSTRACT FROM AUTHOR]

Currently, there are many uses of metal complexes, especially in the fields of medicinal chemistry and catalysis. Thus, fabrication of new complexes which perform as a catalyst and chemotherapeutic drug is always a beneficial addition to the literature. Herein, we report three heterocyclic thiosemicarbazone-based Pd(II) complexes [Pd(HL1)Cl] (C1), [Pd(L2)(PPh3)] (C2) and [Pd(L3)(PPh3)]Cl (C3) having coligands Cl and PPh3. Thiosemicarbazone ligands (H2L1, H2L2 and HL3) and the complexes (C1–C3) were characterized methodically using several spectroscopic techniques. Single-crystal X-ray diffraction methods reveal that the structural environment around the metal center of C2 is square planar, while for C1 and C3 it is a slighty distorted square plane. The supramolecular network of compounds was built via hydrogen bonds, C–H⋯π and π⋯π interactions. Density functional theory (DFT) study of the structure of the complexes supports experimental findings. The application of these complexes as catalysts toward Suzuki–Miyaura coupling reactions has been examined with various aryl halides and phenyl boronic acid in PEG 400 solvent. The complexes displayed good biomolecular interactions with DNA/protein, with a binding constant value of the order of 105 M−1. C3 showed greater binding efficacy toward these biomolecules than the other complexes, which might be due to the cationic nature of C3. Furthermore, antitumor activity of the complexes was studied against the human triple-negative breast cancer (TNBC) cell line MDA-MB-231. It was found that C3 was more toxic (IC50 = 10 ± 2.90 μM) toward MDA-MB-231 cells than the other complexes. A known chemotherapeutic drug, 5-fluorouracil, was included as positive control. The programmed cell death mechanism of C3 was confirmed. Additionally, complex-induced apoptosis was confirmed and occurred via a mitochondria-dependent (intrinsic) pathway. [ABSTRACT FROM AUTHOR]

This work describes the synthesis of eight new Pd(II) and Pt(II) complexes with the general formula [M(TSC)Cl], where TSC represents the 4N-monosubstituted thiosemicarbazone derived from 2-acetylpyridine N-oxide with the substituents CH3 (H4MLO), C2H5 (H4ELO), phenyl (H4PLO) and (CH3)2 (H4DMLO). These complexes have been characterized by elemental analysis, molar conductivity, IR spectroscopy, 1H, 13C, 195Pt and ESI-MS. The complexes exhibit a square planar geometry around the metallic center coordinated by a thiosemicarbazone molecule acting as a donor ONS-type pincer ligand and by a chloride, as confirmed by the molecular structures of the complexes, [Pd(4ELO)Cl] (3) and [Pd(4PLO)Cl] (5), determined by single-crystal X-ray diffraction. The 195Pt NMR spectra of the complexes of formulae [Pt(4PLO)Cl] (6) and [Pt(4DMLO)Cl] (8) in DMSO show a single signal at −2420.4 ppm, confirming the absence of solvolysis products. Complexes 3 and 5 have been tested as catalysts in the Suzuki–Miyaura cross-coupling reactions of aryl bromides with phenylboronic acid, with yields of between 50 and 90% [ABSTRACT FROM AUTHOR]

The New Journal of Chemistry, published by The Royal Society of Chemistry, has released its latest issue containing a variety of articles on different topics in chemistry. The articles cover subjects such as photophysicochemical properties, synthesis of novel compounds, and catalytic reactions. Some specific topics explored in the papers include the synthesis of fluorescent compounds, structural dynamics of phosphorus-containing diesters, emission properties of glass ceramics, and the influence of different cations on spectral properties. Other papers discuss luminescence in lead-free perovskites, synthesis of materials for supercapacitors, photocatalytic activities of nanocomposites, and the adsorption and separation of composite pollutants. The journal aims to connect the world with the chemical sciences. [Extracted from the article]

Fifteen new coordination binuclear compounds of copper(II) were synthesized based on substituted 4-tert-butyl-2,6-bis(N4-thiosemicarbazonyl)phenol (H3L1–3) ditopic ligands. The complexes were characterized using FT-IR spectroscopy, elemental analysis, MALDI-TOF analysis and X-ray diffraction studies highlighting the formation of dinuclear species with various bridging ligands between the two copper(II) atoms and in some cases the dimerization of these species into tetranuclear complexes. The antioxidant, antimicrobial and antifungal activities of ligands and their copper(II) coordination complexes have been investigated. In particular, the complexes show similar or better antimicrobial and antifungal properties than the drugs commonly used in this field. The structure–biological activity relationship is discussed based on the nature of the ligand and the copper salt used in the synthesis of the complexes. [ABSTRACT FROM AUTHOR]

Quantitative extraction of the Pd(II) complex with 5-Chlorosalicylaldehyde thiosemicarbazone (CSTSC) was achieved at pH levels ranging from 3.6 to 4.4 after a 30-second equilibration period in n-butyl acetate. When the concentration of Pd(II) does not exceed 9.0 µg mL-1, the complex formed between Pd(II) and 5-Chlorosalicylaldehyde thiosemicarbazone complies with Beer's law, and it displays the highest absorbance at 400 nm. By means of the mole ratio method and the Jobs continuous variation method, it was determined that the stoichiometry of the Pd(II)-CSTSC complex is 1:2. The stability of the extracted complex persisted for 96 hours. The calculated Sandell's sensitivity was 9.92 x 10-3 µg cm-2, while the molar absorptivity was found to be 1.072 x 104 L mol-1 cm-1. Utilizing this method, effective analysis has been carried out on synthetic samples, complexes, and water samples. [ABSTRACT FROM AUTHOR]

In this study, we synthesized a new thiosemicarbazone derivative molecule (5) that exhibits sensor properties. The characterization of the synthesized molecule was performed using spectroscopic methods such as 1H−, 13C–NMR, FT–IR and Q–TOF. PVC‐membrane ion‐selective sensors were prepared in which the synthesized molecule was used as an ionophore. Surface images of the prepared sensors were examined by scanning electron microscope (SEM) technique. The prepared sensors exhibited selectivity towards barium(II) ions. The developed barium(II)‐selective sensor had a low detection limit of 5.54×10−7 M in the concentration range of 1.0×10−1–1.0×10−6 M. The proposed barium(II)‐selective sensor had fast response time, good repeatability and stability, and can be manufactured with low cost. The sensor can detect barium(II) ions in various water samples with very high recoveries. [ABSTRACT FROM AUTHOR]

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Biodiesel has several drawbacks, such as being prone to oxidation, having reduced stability, and having limited storage time. Antioxidants compatible with biodiesel are being used to address its drawbacks. Utilizing antioxidants effectively improves the quality of biodiesel. Enhancing the quality of biodiesel for use as a clean energy source benefits both the global economy and ecology. Therefore, we believe that our work will contribute to the advancement of the biodiesel industry worldwide. This study used blends consisting of 20% biodiesel and 80% diesel fuel. Isatin-thiosemicarbazones were tested as additives in blends at a concentration of 3000 parts per million (ppm) using an oxifast device and were compared with the chemical antioxidant Trolox. FT-IR, DSC, and TGA were used to characterize these samples. DSC measured sample crystallization temperatures (Tc). Samples with antioxidants showed decreased values compared to the non-antioxidant diesel sample D100. Several DSC tests were conducted to determine the antioxidant strengths of various samples. The results show that the FT-IR spectrum's antioxidant effect regions grow clearer with antioxidants. The extra antioxidant is effective. Biodiesel's oxidative stability improves with isatin-thiosemicarbazones at varying concentrations. The kinetics of thermal decomposition of isatin-thiosemicarbazones under non-isothermal conditions were determined using the Kissinger, Ozawa, and Boswell techniques. The activation energies of compounds 1 and 2 were calculated as 137–147 kJ mol−1 and 173–183 kJ mol−1, respectively. [ABSTRACT FROM AUTHOR]

An important component of the pathogenicity of potentially pathogenic bacteria in humans is the urease enzyme. In order to avoid the detrimental impact of ureolytic bacterial infections, the inhibition of urease enzyme appears to be an appealing approach. Therefore, in the current study, morpholine-thiophene hybrid thiosemicarbazone derivatives (5a-i) were designed, synthesized and characterized through FTIR, 1H NMR, 13C NMR spectroscopy and mass spectrometry. A range of substituents including electron-rich, electron- deficient and inductively electron-withdrawing groups on the thiophene ring was successfully tolerated. The synthesized derivatives were evaluated in vitro for their potential to inhibit urease enzyme using the indophenol method. The majority of compounds were noticeably more potent than the conventional inhibitor, thiourea. The lead inhibitor, 2-(1-(5-chlorothiophen-2-yl)ethylidene)- N-(2-morpholinoethyl)hydrazinecarbothioamide (5g) inhibited the urease in an uncompetitive manner with an IC50 value of 3.80 ± 1.9 μM. The findings of the docking studies demonstrated that compound 5g has a strong affinity for the urease active site. Significant docking scores and efficient binding free energies were displayed by the lead inhibitor. Finally, the ADME properties of lead inhibitor (5g) suggested the druglikeness behavior with zero violation. [ABSTRACT FROM AUTHOR]

A series of hydrazinyl thiazol-4-one based scaffolds (EBHT1-ETHT5) had been prepared through condensation process of substituted thiosemicarbazone with ethyl bromoacetate and sodium acetate. The structure confirmation of formed compounds was done through several spectroscopic methods. Beside synthesis, quantum chemical investigations were executed at MPW1PW91/6-311G(d,p) functional to explore nonlinearity of EBHT1-ETHT5. At first, the structures of prepared chromophores were optimized to get true minima geometries. These optimized geometries were further utilized to carry out the natural bond orbitals (NBO), transition density matrix (TDMx), UV-Vis analysis, density of states (DOS), and nonlinear optic (NLO) characteristics. A minimum Egap (4.433 eV) was achieved in EBHT1 with wider absorption spectrum (λmax= 339 nm) than that of other yielded compounds. A significant charge transference is seen with in molecules through DOS and TDM findings. The GRPs findings explored that all the afore-said chromophores had higher value of global hardness (η = 4.433–4.657 eV) along with lower softness (σ = 0.432–0.277 eV). Significant NLO results were obtained for prepared chromophores as compared to reference urea chromophore. These organic chromophores can be considered as potential candidates in NLO-based applications. [ABSTRACT FROM AUTHOR]

Herein, the chemical synthesis of new thiazole-based benzenesulfonamide-linked morpholine 4a,b–7via late-stage thiazolation of the corresponding thiosemicarbazone 3 is reported. The skeletal formulas of the new compounds were confirmed via instrumental analysis (FT-IR, NMR, and EI-MS). Their structural geometry optimization and the related quantum chemical descriptors were predicted via DFT-B3LYP/6-31G(d) calculations. Their antimicrobial screening demonstrated that all the tested compounds except 4a and b showed antibacterial efficacy against multidrug-resistant Klebsiella pneumoniae with an inhibition zone ranging from 10 to 15 mm. Compound 7, which bears a 4-thiazolone moiety, is the most potent towards K. pneumoniae with an inhibition zone diameter (IZD) of 15 mm and is the sole molecule that exhibited broad-spectrum antimicrobial activity against all pathogenic bacterial and fungal strains with an IZD spanning from 11 to 18 mm. Enzymatic in vitro bioassays indicated that 7 is more potent towards DHFR (IC50 = 0.521 ± 0.027 μg mL−1) than DNA gyrase (IC50 = 6.14 ± 0.27 μg mL−1). The best action mode via molecular docking disclosed that 7 is interlocked into the cavity centre of DHFR with a lower binding fitness (−123.615 kcal mol−1) than DNA gyrase (−112.537 kcal mol−1), validating the experimental results and showing that the 4-thiazolone-linked methyl ester and sulfonamide units are responsible for the hydrogen bonding interactions. Accordingly, thiazole 7 could be a promising antimicrobial lead candidate. [ABSTRACT FROM AUTHOR]

The reaction between 5-acetylbarbituric acid and 4-dimethylthiosemicarbazide or 4-hexamethyleneiminyl thiosemicarbazide produces 5-acetylbarbituric-4-dimethylthiosemicarbazone (H2AcbDM) and 5-acetylbarbituric-4N-hexamethyleneiminyl thiosemicarbazone (H2Acbhexim). Eight new complexes with different copper(II) salts have been prepared and characterized using elemental analysis, molar conductance, UV–Vis, ESI-HRMS, FT-IR, magnetic moment, EPR, and cyclic voltammetry. In addition, three-dimensional molecular structures of [Cu(HAcbDM)(H2O)2](NO3)·H2O (3a), [Cu(HAcbDM)(H2O)2]ClO4 (4), and [Cu(HAcbHexim)Cl] (6) were determined by single crystal X-ray crystallography, and an analysis of their supramolecular structure was carried out. The H-bonded assemblies were further studied energetically using DFT calculations and MEP surface and QTAIM analyses. In these complexes, the thiosemicarbazone coordinates to the metal ion in an ONS-tridentate manner, in the O-enolate/S-thione form. The electrochemical behavior of the thiosemicarbazones and their copper(II) complexes has been investigated at room temperature using the cyclic voltammetry technique in DMFA. The Cu(II)/Cu(I) redox system was found to be consistent with the quasi-reversible diffusion-controlled process. [ABSTRACT FROM AUTHOR]

New derivatives of 3-R-5-chloromethyl-1-thiocarbamoylpyrazole have been synthesized by the intramolecular heterocyclization of thiosemicarbazones of unsaturated ketones, obtained by the interaction of 3,4-dichlorobut-2-ene-1-ones with thiosemicarbazide, in a dioxane with a twofold excess of pyridine. The biological activity of a series of the synthesized substances in vitro has been studied and it has been revealed that the synthesized functional derivatives of pyrazoles show more expressed antimicrobial properties in relation to Staphylococcus aureus, Bacillus cereus, Escherichia coli and Candida albicans. [ABSTRACT FROM AUTHOR]

In the search for a more effective chemotherapy for the treatment of Chagas' disease, caused by Trypanosoma cruzi parasite, the use of gold compounds may be a promising approach. In this work, four gold(I) compounds [AuCl(HL)], (HL = bioactive 5-nitrofuryl containing thiosemicarbazones) were studied. The compounds were theoretically characterized, showing identical chemical structures with the metal ion located in a linear coordination environment and the thiosemicarbazones acting as monodentate ligands. Cyclic voltammetry and Electron Spin Resonance (ESR) studies demonstrated that the complexes could generate the nitro anion radical (NO2−) by reduction of the nitro moiety. The compounds were evaluated in vitro on the trypomastigote form of T. cruzi and human cells of endothelial morphology. The gold compounds studied showed activity in the micromolar range against T. cruzi. The most active compounds (IC50 of around 10 μM) showed an enhancement of the antiparasitic activity compared with their respective bioactive ligands and moderate selectivity. To get insight into the anti-chagasic mechanism of action, the intracellular free radical production capacity of the gold compounds was assessed by ESR and fluorescence measurements. DMPO (5,5-dimethyl-1-pirroline-N-oxide) spin adducts related to the bioreduction of the complexes and redox cycling processes were characterized. The potential oxidative stress mechanism against T. cruzi was confirmed. [ABSTRACT FROM AUTHOR]

The current research reports the synthesis of a library of thiosemicarbazones (3-16) through a two-step chemical transformation. All the synthesized derivatives were purified and fully characterized through mass spectrometry, NMR spectroscopy (1H-, and 13C-NMR), and IR spectroscopy. All the members of the synthesized library were found to be new except compound 8. The synthesized library was screened for its inhibition potential against the urease enzyme. Almost all the compounds exhibited potent activity with the IC50 = 5.3 ± 0.8 − 15.5 ± 0.6 µM in comparison to the thiourea and acetohydroxamic acid used as standard (IC50 = 21.1 ± 0.2, 20.5 ± 0.4 µM). While significant activity was exhibited by compounds 14 and 15 with the IC50 = 23.6 ± 0.6 and 27.3 ± 1.2 µM. Furthermore, kinetic studies were carried out to determine the inhibition mode and molecular docking was employed to recognize the ligand-enzyme interactions. Thereby, the docking results are well in the direction of the in vitro results. Compounds ((E)-N-(2,5-dichlorophenyl)-2-(4-fluorobenzylidene)hydrazine-1-carbothioamide (3) and (E)-2-(2-chlorobenzylidene)-N-(2-fluorophenyl) hydrazinecarbothioamide (5) were identified as the most potent inhibitors of urease by both the in vitro and in silico studies. [ABSTRACT FROM AUTHOR]

Thiosemicarbazone metal complexes are intriguing molecules with a variety of applications in several fields, including the pharmaceutical sector, analytical chemistry, and textile industries. Here, we designed and synthesized 12 transition metal complexes based on thiosemicarbazone as a tridendate group and azo moiety as a chromophore part, in addition to evaluating their color strength and fastness properties. The tridentate ligand derivatives of 5-(m-tolyldiazenyl)salicylaldehyde thiosemicarbazone reacted with four transition metal salts (copper, cobalt, nickel, and iron salts) in refluxing alkaline ethanol to afford the corresponding thiosemicarbazone complexes. The ligands behaved as double-deprotonated tridentate ligands that connected to the transition metal ions through the deprotonation of phenolic-OH and thiol-SH, as well as the azomethine nitrogen atom, to generate fused five- and six-membered heterocycle rings. The obtained metal complexes were characterized by elemental analyses, atomic absorption, IR, and UV–Vis spectra. The color strength and fastness properties of the printed fabrics were tested, showing good to excellent properties. [ABSTRACT FROM AUTHOR]

New Co (II), Ni (II), and Cu (II) complexes based on ρ‐dimethylaminobenzaldehyde thiosemicarbazone (DABT) as chelating agents were synthesized. The structure of the three complexes was determined by elemental analysis and TGA with IR, UV–Vis, XRD, ESR spectra, conductivity, and magnetic measurements. It was found that the isolated DABT complexes have tetrahedral structure with a neutral nature. The antitumor activity of DABT complexes using viability assay was examined against hepatocellular carcinoma cell lines (HepG‐2). The DABT complexes have moderate activity with respect to the standard drugs. DABT–Ni (II) complex has higher antitumor activity (IC50 = 12 μM) than the other DABT complexes. In addition, a molecular docking study was performed for DABT and its complexes to investigate their therapeutic features as topoisomerase inhibitors. It is clear that the most effective compound was DABT–Ni (II) complex to bind to 3QX3. Also, density functional theory calculations with the structure–activity relationship were computed for DABT and its complexes using the Gaussian program. There was confirmation between the obtained theoretical data and the experimental studies. [ABSTRACT FROM AUTHOR]

The extensive industrial use of organic dyes causes large amounts of these substances to arrive at water sources, so nowadays, organic compound removal from fresh water is a major concern. The use of photocatalysts is an interesting approach to solving this problem, with coordination compounds playing an outstanding role. We report the selective synthesis and characterization of three new dissymmetric bis(thiosemicarbazone) ligands and their nickel(II) and zinc(II) complexes, which have been fully characterized by several techniques. The photocatalytic activity of the six complexes for methyl orange degradation was also evaluated. All the complexes can degrade this organic dye, although the photoefficiency of the nickel compounds is, in general, higher than for the zinc ones, as the degradation is faster and they do not reach a plateau. Density functional theory calculations show a clear dependence of the highest occupied molecular orbital (HOMO)–lowest unoccupied molecular orbital (LUMO) gap, as well as with the relative energies of these orbitals. On the other hand, the need for green fuels that do not produce the greenhouse effect is one of the major goals of modern life, and molecular hydrogen is one of the most promising ones. Considering the proven potential of bis(thiosemicarbazone) complexes to electrocatalyze H2 evolution recently reported in the literature, we also made some preliminary tests to investigate the potential of the nickel complexes to act as photocatalysts for water splitting. The results indicate that two of the complexes produce H2 in the conditions tested, so they could be used in the development of efficient photocatalytic systems for hydrogen evolution. [ABSTRACT FROM AUTHOR]

Several heterocyclic compounds bearing an imidazo(1,2a)pyridine moiety have been synthesized in this work, including triazole, thiazol, and thiazolone. This was done by condensation of 2-aminopyridine with 2-aminopyridine with 4- bromophencyl bromide or 4-phenylphencyl bromide to produce 2-substituted phenyl imidazo(1,2a)pyridine compounds 1 and 2. The Vilsmeier-Haak reaction was used to create the aldehyde group at position 3 of the 2-substituted phenyl imidazo(1,2a)pyridine ring (3 and 4). The reaction of compounds 3 and 4 with thiosemicarbazide afforded thiosemicarbazone derivatives 5 and 6 in 66 and 70% yields, respectively. These derivatives (5 and 6) were then subjected to three different cyclization reactions to obtain 1,3-thiazolone (7 and 8), 1,2,4-triazole (9 and 10), and 1,3-thiazole (11 and 12) derivatives. The FT-IR spectroscopy was used to confirm the structure of these derivatives, and the 1H NMR spectroscopy was used for some of them. A few of the produced compounds were examined for antimicrobial and antioxidant activities [ABSTRACT FROM AUTHOR]

Cu‐thiosemicarbazones have been intensively investigated for their application in cancer therapy or as antimicrobials. Copper(II)‐di‐2‐pyridylketone‐4,4‐dimethyl‐thiosemicarbazone (CuII‐Dp44mT) showed anticancer activity in the submicromolar concentration range in cell culture. The interaction of CuII‐Dp44mT with thiols leading to their depletion or inhibition was proposed to be involved in this activity. Indeed, CuII‐Dp44mT can catalyze the oxidation of thiols although with slow kinetics. The present work aims to obtain insights into the catalytic activity and selectivity of CuII‐Dp44mT toward the oxidation of different biologically relevant thiols. Reduced glutathione (GSH), L‐cysteine (Cys), N‐acetylcysteine (NAC), D‐penicillamine (D‐Pen), and the two model proteins glutaredoxin (Grx) and thioredoxin (Trx) were investigated. CuII‐Dp44mT catalyzed the oxidation of these thiols with different kinetics, with rates in the following order D‐Pen>Cys≫NAC>GSH and Trx>Grx. CuII‐Dp44mT was more efficient than CuII chloride for the oxidation of NAC and GSH, but not D‐Pen and Cys. In mixtures of biologically relevant concentrations of GSH and either Cys, Trx, or Grx, the oxidation kinetics and spectral properties were similar to that of GSH alone, indicating that the interaction of these thiols with CuII‐Dp44mT is dominated by GSH. Hence GSH could protect other thiols against potential deleterious oxidation by CuII‐Dp44mT. [ABSTRACT FROM AUTHOR]

The article discusses the bioinorganic chemistry of copper, highlighting its essential role in biological systems and its involvement in various biological functions. Copper compounds exhibit different configurations and oxidation states, leading to diverse reactivity and nuclearity. The article also explores the role of copper in neurodegenerative diseases and the development of new copper-containing coordination complexes with potential pharmacological properties, particularly in anticancer activities. The special issue of the journal Inorganics contains 14 articles that cover topics such as antiproliferative studies, anticancer agents, anti-inflammatory compounds, and potential diagnostic agents. [Extracted from the article]

1H-Indole-2,3-dione 3-[4-(4-sulfamoylphenyl)thiosemicarbazones] 6a-j were evaluated against para-influenza-3, reovirus-1, sindbis, coxsackie B4, and Punto Toro viruses. New 1-methyl-1H-indole-2,3-dione 3-[4-(4-sulfamoylphenyl) thiosemicarbazones] 7a-c were synthesized to evaluate the contribution of methyl substitution at position 1 of the indole ring to antiviral activity. The test results showed that 5-trifluoromethoxy substituted compound 6c (EC50 2-9 μM) and 5-bromo substituted 6f (EC50 2-3 μM) have non-toxic selective antiviral activity, while not all standards are active against reovirus-1. Molecular docking studies of 6c and 6f were carried out to determine the possible binding positions with reovirus-1. Trifluoromethoxy and bromine substitutions at position 5 of the indole ring provided selective antiviral activity, while methyl substitution at position 1 of the indole ring significantly decreased the activity against reovirus-1 and increased toxicity. [ABSTRACT FROM AUTHOR]

Thiosemicarbazones derived from 3-acetylfuran-2(5H)-ones reacted with diethyl acetylenedicar-boxylate in anhydrous ethanol, as well as with maleic anhydride in chloroform, to produce new derivatives containing furan-2(5H)-one and 4-oxothiazolidine fragments. The synthesized compounds were characterized by NMR spectra and elemental analyses. [ABSTRACT FROM AUTHOR]

Ten derivatives of phenylbenzylidene thiosemicarbazones (1–10) were synthesized by multicomponent reaction between hydrazine hydrate, isothiocyanate and substituted aldehydes in the presence of the phase transfer reagent Triton-B and subsequently heating the mixture. The synthesized compounds 1, 2, 5, 8 demonstrated to act as highly potent anticancer agents. They showed anticancer activity by mobilizing cellular 59Fe, inhibiting cellular uptake of 59Fe from 59Fe2-Tf, and mediating the ascorbate oxidation. Further, the structure activity relationship revealed that the donor atom and its stabilization resulted in better anticancer activity. The softness of the chelating donor atoms N and S yielded redox active iron complexes, which easily mediated ascorbate oxidation. This study identified the selective and potential chelators, which may act as anticancer agents and require further in vivo screening in future. [ABSTRACT FROM AUTHOR]

Nowadays, the search for new chemotherapeutic agents with low toxicity and high selectivity is a major concern. In this paper, we report the synthesis and characterization of a hybrid thiosemicarbazone/hydrazone ligand in its neutral form (L1H2) and as the chloride salt ([L1H3]Cl)-, three diorganotin (IV) complexes, and one complex with Sn (IV). The compounds have been fully characterized by IR, mass spectra, 1H, 13C, and 119Sn NMR, 119Sn CP/MAS NMR, and by single crystal X-ray diffraction. The organotin compounds have the empirical formula [SnR2L1] (R = Me, Bu, and Ph), but in the solid state, they are polymeric species with seven coordination number due to weak coordination of the pyridine nitrogen, whereas in solution, the polymeric structure is lost to afford hexacoordinate monomeric species. Reaction with SnI4 yields complex [Sn (L1)2]·EtOH, with the metal in a distorted dodecahedral arrangement. We have evaluated the antiproliferative activity of the two forms of the ligands and the four coordination compounds against MDA-MB-231, HeLa, PC3, and HepG2 cancer cell lines, and WI-38 normal cell line, and all the compounds present higher activity than cisplatin, used as the standard control. To investigate the mode of action, we have selected the most active complex, containing phenyl substituents, and used the triple negative breast cancer cell line MDA-MB-231. The results show that the complex induces apoptotic cell death promoted by generation of reactive oxygen species and by disruption of mitochondrial membrane potential. [ABSTRACT FROM AUTHOR]

In this research investigation, a total of eighteen diverse tetra- and penta-lateral cyclic compounds were synthesized. These included 1,3,4-thiadiazole, thiazolidin-4- one (via an alternative method), 1,2,4-triazole, carbothioamide, thiazole-4-one, azetidin-2-one, and oxazole. The synthesis procedure entailed a sequence of reactions. The thiazolidine-4-one 1 was obtained by reaction p-aminobenzoic acid with thiosemicarbazide, followed by treatment with p-tolualdehyde to produce Schiff base 2. Reaction Schiff base 2 with mercaptoacetic acid in dry benzene was carried out to produce thiazolidine-4-one 3. In another synthesis pathway, the esterification of p-nitro benzoic acid with ethanol in the presence of sulfuric acid was obtained to formation of compound 4. Compound 4 was subsequently reacted with thiosemicarbazide, yielding compound 5. Cyclization of compound 5 was then achieved using 4% sodium hydroxide solution. This formed the 1,2,4-triazole heterocycle, designated compound 6. Thiosemicarbazone 7-9 were prepared by reaction of thiosemicarbazide with different aldehydes. Additionally, 2-substituted1,3-thiazolidine-4-one derivatives 10-12 were synthesized through the reaction of thiosemicarbazone with chloroacetic acid in the presence of anhydrous sodium acetate. The Oxazole derivative 15 was obtained through a series of reactions starting with the reaction of p-amino benzoic acid with ethyl chloroacetate, resulting in compound 13. Compound 13 was then treated with urea to obtain compound 14, followed by a reaction with 4-phenyl phenacyl bromide to yield the final product, the Oxazole derivative 15. The 2-aminooxadiazole derivative 16 was synthesized by reaction urea with 4-bromoacetophenone which was reacted with 4- bromobenzaldehyde to produce Schiff base derivative 17. Finally, β-lactam 18 is obtained through reaction Schiff base with chloroacetyl chloride in the presence of triethyl amine. FT-IR, 1H-NMR, and 13C-NMR spectroscopy were used to confirm their proposed structures. Moreover, the antibacterial and antifungal activities of certain synthesized compounds, specifically 2,3,6,11,13,15,17, and 18, were assessed against Staphylococcus aureus, Escherichia coli, and Candida albicans, demonstrating encouraging outcomes.Keywords: Antibacterial, antifungal activity, oxadaizole, heterocyclic derivatives, Oxazole. [ABSTRACT FROM AUTHOR]

In an attempt to develop new thiazinanones, 2-oxoacenaphthylen-1(2H)-ylidene)hydrazineylidene)-5,6-diphenyl-1,3-thiazinan-4-ones were synthesized via the reaction of oxoacenaphthylen-hydrazinecarbothioamide derivatives with 2,3-diphenylcycloprop-2-enone in ethanol and catalyzed by triethyl amine. The structure of the obtained thiazinanones was elucidated by spectral data (IR, MS, 1H and 13C NMR spectra) in addition to elemental analysis. The mechanism describes the reaction pathway was also discussed. [ABSTRACT FROM AUTHOR]

The electronic structure, solvatochromic and some optoelectronic properties of five different thiosemicarbazone (TSCs) derivatives with different substituents consisted from indole ring, benzyl ring and conjugated thiosemicarbazide have been investigated in detail. UV–vis. absorption spectra of TSC compounds have been analyzed in solvent media with different polarity. The spectral changes are observed to forming of solvent effects and substituents. Spectral behaviors and electronic transitions are interpreted based on the UV-Vis. spectra. Solvatochromic behaviors were defined by linear solvation energy relationships via multiple linear regression analysis by using Kamlet-Abboud-Taft and Catalán parameters. In addition, the correlations of electronic absorption transition energy with Marcus optical dielectric parameter and Reichardt-Dimroth parameter were also determined. Some optoelectronic parameters such as forbidden band gap energy and refractive index have been determined in different solvent medium. Thiosemicarbazone derivatives have a global electronic absorption transition energy of about 3.351 eV. According to LSER calculations, polarizability-induction of electronic transitions of the investigated molecules is effective. The (E)-4-(4-nitrobenzyl)-1-(2-oxo-2H-indol-3(3aH)-ylidene)thiosemicarbazide (TSC-B) compound that does not a methoxy group and contain nitro group substituent and has the highest forbidden energy range. [ABSTRACT FROM AUTHOR]

4-ethylthiosemicarbazide in ethanol facilitated by acid catalysis. There is one crystallographically independent molecule in the asymmetric unit, which shows disorder of the terminal ethyl group of the jasmone carbon chain [site-occupancy ratio = 0.911 (5):0.089 (5)]. The thiosemicarbazone entity [N--N--C(S)--N] is approximately planar, with the maximum deviation of the mean plane through the N/N/C/S/N atoms being 0.0331 (8) Å, while the maximum deviation of the mean plane through the five-membered ring of the jasmone fragment amounts to - 0.0337 (8) Å. The dihedral angle between the two planes is 4.98 (7)°. The molecule is not planar due to this structural feature and the sp³-hybridized atoms of the jasmone carbon chain. Additionally, one H...N intramolecular interaction is observed, with graph-set motif S(5). In the crystal, the molecules are connected through pairs of H...S interactions with R2²(8) and R2¹(7) graph-set motifs into centrosymmetric dimers. The dimers are further connected by H...N interactions with graph-set motif R2²(12), which are related by an inversion centre, forming a mono-periodic hydrogen-bonded ribbon parallel to the b-axis. The crystal structure and the supramolecular assembly of the title compound are compared with four known cis-jasmone thiosemicarbazone derivatives (two crystalline modifications of the non-substituted form, the 4-methyl and the 4-phenyl derivatives). A Hirshfeld surface analysis indicates that the major contributions for the crystal cohesion are from H...H (70.7%), H...S/S...H (13.5%), H...C/C...H (8.8%), and H...N/N...H (6.6%) interfaces (only the disordered atoms with the highest s.o.f. were considered for the evaluation). [ABSTRACT FROM AUTHOR]