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Bidentate Schiff bases (I1–I9) are synthesized by condensation between substituted anilines, benzothiazoles, and 2-hydroxy aromatic aldehydes. The Zn(II) derivatives (1–9) are prepared by reacting the respective ligand and zinc acetate dihydrate in a 2:1 mole ratio in dry methanol using triethylamine as a base. They are characterized by FTIR, NMR, and single-crystal XRD techniques. The XRD data confirmed distorted tetrahedral molecular geometry for 6; the intermolecular interactions are investigated comprehensively by 3-D Hirschfeld surface analysis and 2-D fingerprint plots. The DFT studies for the compounds are conducted for geometrical and energy optimization by applying 3-21 G* and 6-311++G (d, p)/B3LYP basis sets. Molecular docking data show that ligands possess GOLD scores in the range 51.5–46.7, whereas 2 and 3 have shown good fitness score of 57.7 and 53.3, respectively, with a maximum score of 60.2 for 7. The antibacterial data for 7 shows zone of inhibition as 17.3 mm against Staphylococcus aureus and 16.3 mm against Staphylococcus epidermidis, whereas 2 exhibits maximum value of 15.6 mm against gram negative bacteria Escherichia coli. The maximum and comparable alpha amylase inhibition potential of 12.6 and 12.3% are found for 8 and 3, respectively. [ABSTRACT FROM AUTHOR]

A series of imidazolium‐based symmetrical and asymmetrical dicationic ionic liquids (DcILs) with alkyl spacers of different length and with [FeCl3Br]− as counter ion have been synthesized. The synthesized DcILs are characterized by using FTIR and Raman spectroscopy as well as mass spectrometry, along with single‐crystal XRD analysis. Physicochemical properties such as solubility, thermal stability and magnetic susceptibility are also measured. These compounds show low melting points, good solubility in water and organic solvents, thermal stability, and paramagnetism. The products of molar susceptibility and temperature (χmol⋅T) for the synthesized DcILs have been found between 4.05 to 4.79 emu mol−1 K Oe−1 and effective magnetic moment values have also been determined to be compared to that expected from the spin‐only approximation. [ABSTRACT FROM AUTHOR]

In a quest to discover new formulations for the treatment of various parasitic diseases, a series of heteroleptic triorganobismuth(V) biscarboxylates of type [BiR3(O2CR′)2], where R=C6H5 for 1–4 and p-CH3C6H4 for 5–8, were synthesized, characterized and evaluated for their biological potential against L. tropica. All the synthesized complexes were fully characterized by elemental analysis, FT-IR, multinuclear (1H and 13C) NMR spectroscopy and X-ray crystallography. The crystal structures for [BiPh3(O2CC6H4(o-Br))2] (1), [BiPh3(O2CC2H2C6H4)2] (2), [BiPh3(O2CC6H4(m-NO2))2] (3) and [BiPh3(O2CC6H4(2-OH,3-CH3))2] (4) were determined and found to have a distorted pentagonal bipyramidal molecular geometry with seven coordinated bismuth center for 1–3 and for 4 distorted octahedral geometry, respectively. All the synthesized complexes demonstrated a moderate to significant activity against leishmania parasites. A broad analytical approach was followed to testify the stability for (1–8) in solid state as well as in solution and in leishmanial culture M199, ensuring them to be stable enough to exert a significant antileishmanial effect with promising results. Cytotoxicity profile suggests that tris(tolyl) derivatives show lower toxicity against isolated lymphocytes with higher antileishmanial potential. Molecular docking studies were carried out to reveal the binding modes for (1–8) targeting the active site of trypanothione reductase (TR) (PDB ID: 4APN) and Trypanothione Synthetase-Amidase structure (PDB ID 2vob). [ABSTRACT FROM AUTHOR]

A series of ferrocenyl substituted hydrazones (I–VII) derived from ferrocene carboxaldehyde and substituted hydrazides have been prepared and characterized by FTIR, 1H NMR spectroscopy, and crystallographic studies. The single-crystal X-ray analysis for III·0.5H2O·0.5CH3CN (CIF file CCDC no. 1968937) further authenticates the structural motif of the synthesized compounds. The C(11) of ferrocene carboxaldehyde is linked with N(1) of the hydrazide moiety with a bond length of 1.283(5) Å, confirming the binding of the two structural units present in the final product. They were preliminarily screened for their antimicrobial activity and demonstrate good results. The free radical scavenging activity for the compounds (III, IV) has been found to be more than 90% when compared with the ascorbic acid. The total antioxidant capacity and total reducing power assays for VI show significant activity whereas the data for the other compounds are also encouraging. Quantum chemical calculations at the DFT level predict that compound II is the softest while VII is the hardest within the series, resultantly II can be used as a synthon for further chemical reactions. [ABSTRACT FROM AUTHOR]

Six new heteroleptic tri-organobismuth(V) complexes (1-6), of general formula, R3Bi(OOCR')2 where R = C6H5 (1-3), p-CH3C6H4 (4-6) and R' represents deprotonated 2-(methylthio)nicotinic acid (1, 4); 3-thiophenecarboxylic acid (2, 5) and 4-chlorosalicylic acid (3, 6) have been synthesized and characterized by FT-IR, NMR (1H, 13C) and single crystal XRD techniques in addition to elemental analyses. The solid-state structure for 3 has also been elucidated by crystallographic data, manifesting its distorted trigonal bipyramidal molecular geometry with a five-coordinate bismuth center. The carboxylate ligand(s) assume a monodentate coordination mode as predicted by IR and then confirmed by XRD data. The antibacterial, antifungal and antileishmanial potential for 1-6 have been evaluated and the preliminary screening data suggest significant to average biological activities. The antileishmanial activity data manifest comparatively lower IC50 value for 5 than the standard drug. A comprehensive study for 1-6 was also undertaken to testify their stability both in solid and solution phases as well as in leishmanial culture M199, which demonstrate high degree of stability that may ensure their significant antileishmanial effect. The % viability values of the organobismuth(V) bis-carboxylates highlight their role as significantly effective compounds, having potential candidature for future drug discovery and development processes. [ABSTRACT FROM AUTHOR]

Eight ionic liquids have been synthesized with the tetrachloroferrate anion and varying cations with the general formula of [RA]+[FeCl4]− (R = –CH3, –CH2C6H5; A = pyridine, benzimidazole, trimethylamine, triphenylphosphine). They were characterized using spectroscopic techniques such as FT-IR, ESI-MS, Raman, and AAS along with single-crystal XRD to validate their structural motifs. The ionic conductivity, electrochemical and magnetic properties were determined to assess their possible uses in synthesis, separation, magnetic and transportation technologies, and high-energy capacitors. The diffusion coefficient value for these compounds was calculated to be around 7.55 × 10−8 cm2 s−1 and the heterogeneous rate constant value is about 3.60 × 10−3 cm s−1, which quantitatively complemented not only quasi reversibility but also moderately fast electron transfer processes. The effective magnetic moment values for the ionic liquids were determined to be similar to that expected from the spin-only approximation. [ABSTRACT FROM AUTHOR]

New Zn(II) complexes (1–8) of general formula [Zn(R)2(L')2], where R = cinnamic acid (1–7), L' = 3-pyridine carboxamide (1), 2,2'-bipyridine (2), 3-pyridinecarbonitrile (3), 2-amino-5-(4-pyridinyl)-1,3,4-thiadiazole (4), 2-methylimidazole (5), 2-phenylimidazole (6), 2-imidazolidinethione (7) and for (8), R = acetic acid; L' = 2-amino-5-(4-pyridinyl)-1,3,4-thiadiazole)2, have been synthesized by a stoichiometric reaction between Zn(II) carboxylate(s) and the respective nitrogen-based ligands. The prepared compounds are analyzed by FTIR, NMR spectroscopy and single crystal X-ray diffraction techniques for their structural manifestations along with elemental analyses. The crystallographic data for 6 and 8 exhibit four-coordinated zinc having distorted tetrahedral molecular geometry. The thermogravimetric data demonstrate high stability of the compounds with gradual loss of acetate and thiadiazol fragments that ultimately lead to zinc oxide as the residual mass of 8. Quantum chemical calculations indicate that 7 is the softest in reactivity having the lowest band gap as determined from the energies of frontier molecular orbitals whereas 8 is highly polar with the highest dipole moment value of 12.61 D. The computational data are a complement to the success of the research. [ABSTRACT FROM AUTHOR]

The crystal structure of a palladium(II) complex of imidazolidine-2-thione (Imt), [Pd(Imt)4]Cl2 (I) was determined by X-ray crystallography (CIF file CCDC no. 1946290). The structure of complex I is ionic consisting of [Pd(Imt)4]2+ cation and two chloride counter ions. The palladium atom in the complex ion assumes a distorted square planar geometry. The complex cation and non-coordinated chloride ions are connected to each other through electrostatic and hydrogen bonding interactions. To compare the stability of I with its corresponding non-ionic species [Pd(Imt)2Cl2] . 2Imt (Ia), DFT calculations were performed in the gas phase as well as in the DMSO solvent. The IR spectra of the ligand Imt and complex I were reliably interpreted theoretically. The structures of two related cyanide complexes; [Pd(Imt)2(CN)2]2 (II) and [Pd(Imt)4][Pd(CN)4] (IIa) were also predicted by DFT calculations in terms of geometries and stability. The DFT results reveal that in the gas phase, the structure I is less stable in comparison to the calculated structure Ia by 11.26 kcal/mol (ΔG) but reverse is true when the DMSO solvent is included in the quantum chemical calculations. For the cyanide analogues, the ionic dinuclear form IIa is more stable than the dimer II of the mononuclear complex [Pd(Imt)2(CN)2] in gas phase by 13.37 kcal/mol but is less stable in calculations with DMSO by 6.86 kcal/mol. [ABSTRACT FROM AUTHOR]

The synthesized thioureas, 1-(3-fluorobenzoyl))-3-(4-(diethyl aminophenyl) thiourea (I1), 1-benzoyl-3-(2-chlorophenyl) thiourea (I2) and 1-(2-fluorobenzoyl)-3-(2-chlorophenyl) thiourea (I3) along with triphenylphosphine were reacted with Cu(I) chloride in mole ratios 1:2:1 by using dry acetone as solvent under nitrogen to get 1–3. The synthesized thioureas and metal derivatives were characterized by spectroscopic techniques such as IR and multinuclear (1H, 13C) NMR. Compound 3 is analyzed by single crystal X-ray analysis and data reveal that the Cu is four coordinate having tetrahedral molecular geometry. The interaction of 1–3 with DNA is ascertained by cyclic voltammetry, determining binding constant, binding energy and diffusion coefficient. The findings suggest that the complexes interact with DNA in an electrostatic mode. The antioxidant activity data show that 3 has the highest free radical scavenging ability having Ic50 value of 10 µg/mL. The synthesized compounds were also screened against various bacterial strains and found some encouraging results. The binding interactions of the metal complexes with a specific protein were further validated by molecular docking studies and the results obtained show their strong interaction with amino acid residue in the binding pocket of the target protein. [ABSTRACT FROM AUTHOR]

Tributyltin(IV) derivative (1) was synthesized by reacting the ligand (A1) {2‐[(2‐methylpropanoyl)amino]propanoic acid} with tributyltin(IV)chloride in presence of potassium hydroxide. The compounds were characterized by elemental analysis, FTIR and multinuclear (1H, 13C and 119Sn) NMR spectroscopy. The 119Sn NMR data for (1) suggest that tin is five coordinated having trigonal bipyramidal molecular geometry. Molecular structures for (1) and (A1) were determined by single crystal X‐ray analysis. Some new and novel structural features of the compounds, are reported first time. Tributyltin(IV) complex has distorted trigonal bipyramidal molecular geometry around tin in the solid state exhibiting single chain tetramer which may be ascribed as tetra‐nuclear cage structure that is constructed from four tributyltin units and four ligand moieties. The tributyltin(IV) entities are bridged by one oxygen of the carboxylic group of one ligand and another oxygen of the amidic carbonyl of next ligand. The nature of Sn...O bond was analyzed with the help of natural bond orbital (NBO) analysis. The compounds were also screened in vitro for their anti‐microbial and urease inhibition activities, and found some encouraging results. [ABSTRACT FROM AUTHOR]

Five new substituted benzamide derivatives as ionic solids are prepared and characterized by FT-IR, 1H, and 13C NMR spectroscopy. The crystal structure for compound 2 is determined by X-ray crystallography. The compounds are bio-assayed for their bactericidal, fungicidal, anti-oxidant, and urease inhibition activities. The molecular docking results accumulated for the compounds correlate with their biological activity and reveal high binding affinity towards jack bean urease. [ABSTRACT FROM AUTHOR]

Five new carboxylic acid precursors bearing thiourea group and their corresponding bismuth(III) complexes were synthesized and characterized using CHNS and inductively coupled plasma analyses and infrared and NMR (1H, 13C) spectroscopies. Single-crystal X-ray diffraction analysis was also carried out for one of the precursors. The behaviour of the compounds was bioassayed for antibacterial, antifungal, antioxidant and enzyme (lipoxygenase, α-glycosidase and anti-urease) inhibition activities. It is concluded that the interaction of the compounds with bismuth enhances both the antimicrobial and enzyme inhibition activities. The synthesized compounds may prove to be good therapeutic agents. [ABSTRACT FROM AUTHOR]

Five new bromobenzoyl thiourea derivatives (1-5) linked with different amino acids were synthesized via the reaction of bromobenzoyl chloride with potassium thiocyanide and the corresponding amines. The synthetic compounds were characterized by single crystal XRD, IR and NMR (¹H- and 13C-) spectroscopy in addition to elemental analysis and melting point determinations. These compounds were also preliminary analyzed for antifungal and antibacterial activity against different strains of fungi and bacteria, respectively. The data suggest that the compounds exhibited promising antimicrobial activity and may prove potential lead compounds as antimicrobial agent. [ABSTRACT FROM AUTHOR]

A series of N, N, N′-trisubstituted thioureas ( 1-12) and their Ni(II) complexes ( 1a-12a) were synthesized and characterized by multinuclear (H and C) NMR, FT-IR spectroscopy and LC-MS techniques in combination with elemental analysis. The crystal structures of both ligands and Ni(II) chelates of type Ni(L- O, S) were determined by single crystal X-ray diffraction analysis. All the complexes were adopted to have square planar geometry, where the N, N, N′-trisubstituted thioureas showed bidentate mode of coordination at nickel centre through oxygen and sulfur atoms. The synthesized complexes were screened for potential inhibitors of Jack bean urease. Compounds 1a and 3a were observed as most potent inhibitors of urease exhibiting IC values of 1.17 ± 0.12 and 1.19 ± 0.41 µM, respectively. Cytotoxicity assay on lung carcinoma (H-157) and kidney fibroblast (BHK-21) cell showed that compounds were significant anticancer agents. Additionally, the complexes were tested against Leishmania major and found to be potent antileishmanial agents. [ABSTRACT FROM AUTHOR]

Bioactive 3-ferrocenylaniline [(η-CH)Fe{CHNH}] has been successfully synthesized and characterized by means of various physico-analytical techniques such as FTIR and multinuclear (H and C) NMR spectroscopy along with melting point and elemental analysis. The interaction of the 3-ferrocenylaniline with DNA has been investigated by spectroscopic and viscometric measurements. The interaction of compound with DNA is presumably occurring via hydrogen bonding. Viscosity measurement of the compound has proved to change in length and is regarded as the least ambiguous and the most critical test of binding model in solution. The antibacterial activity was carried out using Gram-positive bacteria ( Staphylococcus aureus, Micrococcus luteus) and Gram-negative bacteria ( Escherichia coli, Klebsiella pneumoniae) and found to be selective and effective against Gram-positive bacteria. In vitro antifungal activity was determined against the fungal species ( Aspergillus niger and Aspergillus flavus) and demonstrated significant activity. Graphical Abstract: Compound 1 was synthesized from ferrocene and 3-nitroaniline in the presence of sodium nitrite/hydrochloric acid and the resulting product was reduced to 3-ferrocenyl aniline. The compound was characterized by IR, multinuclear (H and C) NMR, and elemental analysis. DNA interaction studies were examined by spectroscopic and viscosity measurements. Antibacterial and antifungal activities are also tested. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Some novel lower homologues of diorganotin derivatives of germyl substituted propanoic acids with general formula [Ar3GeCH(R1)CH(R2)COO]2 [image omitted], where Ar = p-CH3C6H4, C6H5, R1 = p-CH3C6H4, p-CH3OC6H4, o-CH3OC6H4, C6H5, R2 = H, CH3, R3 = CH3, C2H5 have been prepared by the condensation reaction of dialkyltin oxide and triarylgermyl(substituted) propanoic acid in 1 : 2 M ratio, respectively, and were characterized by IR, multinuclear (1H, 13C, 119Sn) NMR, 119mSn Mössbauer spectroscopy. The synthesized compounds were also screened for their toxicity and possible antibacterial, antifungal activities and found some encouraging results. [ABSTRACT FROM AUTHOR]

The phosphorescence bioimaging and sensing applications of Iridium (III) complexes, in particular to subcellular organelle staining as well as sensing of biologically important analytes, have been reviewed here. The bioimaging applications of the metal complexes provide an attractive alternative to fluorescent organic compounds in the construction of biosensors and biolabels because of having certain advantages. [ABSTRACT FROM AUTHOR]

Heteroleptic triorganobismuth (V) complexes of general formula, R3Bi(OOCR')2 (1–7), where R = C6H5 (1–3), p‐CH3C6H4 (4–7) and R' = 3,5‐Cl2C6H3 (1, 5); 3,4,5‐(OCH3)3C6H2 (2, 6); 3‐CH3C6H4 (3,7); 2‐OH‐3‐OCH3C6H3 (4) have been synthesized and fully characterized by FT‐IR, 1H &13C NMR spectroscopy, single crystal X‐ray crystallography and elemental analysis. The molecular geometry observed for the compounds is predominantly distorted trigonal bipyramidal, the fact which was subsequently authenticated through X‐ray analyses for (1–4). All the synthesized compounds have been bio‐assayed for antileishmanial (Leishmania tropica KWH23) and Jack beans urease inhibitory activity, and human Lymphocytes were used to measure the general toxicity. Of these, (4) proved to be highly effective against the target species (Leishmania tropica KWH23), while being non‐toxic towards the mammalian cells at levels below 0.74 μgmL−1, making it highly promising drug candidate. The high activities for (2, 4, and 6) against Jack beans Urease as compared to the reference standard demonstrate their significance in searching of therapeutic agents in future programs. The significant binding score of (2&4) against H. pylori in molecular docking studies further revealed their importance in future drug discovery processes. [ABSTRACT FROM AUTHOR]