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The reaction of Ta(NMe2)5 with CS2 resulted in the isolation of azametallacyclopropane complex [Ta(MeDtc)3(η2-CH2NMe)] (I, MeDtc = dimethyldithiocarbamate), which was characterized by X-ray diffraction in the solvent-free form and as a toluene solvate (CCDC nos. 2005837 (I), 2049693 (I∙0.5C7H8)) and by NMR spectroscopy and DFT calculations.

Herein, we describe the synthesis of coordination compounds starting from carbohydrazide ((H2NHN)2C=O (CHZ)) and the Zn2+ salt of dinitramic acid (HDN), which are high-nitrogen substances that exhibit properties similar to those of a burning-rate inhibitor of pyrotechnic compositions. This study demonstrates that these compounds react with glyoxal to furnish adducts of metal–organic macrocyclic cages bearing the elements of carbohydrazide, complexing metals and the HDN anion, depending on the ratio of the starting reactants. The assembled macrocyclic cage has “host–guest” properties and is a safe container for the storage of HDN salts. X-ray crystallographic analysis of the resultant coordination compound, [Zn(chz)3(N(NO2)2)2]), indicated that the metal–ligand association occurs via the N and O atoms of carbohydrazide. The zinc salt of dinitramic acid, which is enclosed into adducts with a macrocycle, is thermally stable and insensitive to mechanical impacts. The complex zinc salt of dinitramide was shown herein to exhibit inhibitory activity towards the burning rate of pyrotechnic compositions.

Here, we report the study results of the nitration of 3,7,10-trioxo-2,4,6,8,9,11-hexaaza[3.3.3]propellane (THAP) by different nitrating agents such as nitric acid, mixed nitric/sulfuric acids, nitric anhydride, and mixed concentrated nitric acid/acetic anhydride to furnish 3,7,10-trioxo-2-nitro-2,4,6,8,9,11-hexaaza[3.3.3]propellane and 3,7,10-trioxo-2,8-dinitro-2,4,6,8,9,11-hexaaza[3.3.3]propellane, whereas a lactam–lactim rearrangement was found to take place upon vigorous cooling to give 10-hydroxy-2,4,6,8,9,11-hexaazatricyclo[3.3.3.01,5]undec-9-ene-3,7-dione. The two competing reactions, lactam–lactim rearrangement, and nitration were found to take place. The acylation of 3,7,10-trioxo-2,4,6,8,9,11-hexaaza[3.3.3]propellane was examined and the formation conditions of 2,6-di- and 2,6,9-triacetyl-substituted and 3,7,10-trioxo-2,4,6,8,9,11-hexaacetyl-2,4,6,8,9,11-hexaaza[3.3.3]propellane were established. The acetyl derivatives were found to be instable in an acidic medium and to undergo deacylation. The obtained findings correlate well with the quantum-chemical calculations.

Substitution of apical halide ligands in [{Re6Sei8}Xa6]3- (X = Cl, Br) by benzimidazole (bimzH) accompanied by a self-assembly process leads to the formation of microporous Re6-based hydrogen-bonded organic frameworks (Re6-HOFs) constructed on N-H···X hydrogen bonds and π-π-stacking interactions between bimzH ligands. Re6-HOFs demonstrate sorption properties with a Brunauer-Emmett-Teller surface area of up to 443 m2 g-1 and luminescence with a quantum yield and an emission lifetime of up to 0.16 and 16 μs, respectively. The compounds obtained complement small groups of transition-metal cluster-based HOFs, which are a perspective for the development of multifunctional frameworks.

Mixed-ligand amidophenolate complexes [Ta(APDipp)(NMe2)3] (I) and [Ta(APDipp)2(NMe2)] (II) were obtained by the reaction of Ta(NMe2)5 with 2,4-di-tert-butyl-6-((2,6-diisopropylphenyl)amino)phenol (H2APDipp). The products were characterized by X-ray diffraction (CIF file CCDC nos. 2060699 (I), 2060700 (II∙0.5C5H12)) and NMR spectroscopy.

The inheritance of allelic variants of aromatic alcohol dehydrogenase CADim (CAD intermediate) and their effect on the severity of plant traits in spring bread wheat (fluorescence of seedling slices, micromorphology, and chemical composition of tissues) were studied. The plants with contrast CADim genotypes (homozygotes +/+ and –/–) were used to study the tissue autofluorescence, micromorphology, and chemical composition. The thickness of the straw walls in the CADim– genotype is higher than that in the CADim+ genotype, which can affect the resistance of wheat plants to lodging. Differences in the chlorophyll content, particularly, in the ratio of chlorophylls A and B, were observed; this probably affects photosynthesis. An increased content of carbonyl groups in the CADim+ genotype, as well as differences in the cinnamon monomers of lignin, were found. It follows from these results that CADim+ and CADim– allelic variants have a significant effect on a number of plant traits and, consequently, that the polymorphism at the CADim locus is functional, which enables its use in breeding and biotechnology.

Despite the great potential of octahedral tungsten cluster complexes in fields of biomedical applications such as X-ray computed tomography or angiography, there is only one example of a water-soluble W6Q8-cluster that has been reported in the literature. Herein we present the synthesis and a detailed characterization including X-ray structural analysis, NMR, IR, UV–Vis spectroscopies, HR-MS spectrometry, and the electrochemical behavior of two new cluster complexes of the general formula W6Q8L6 with phosphine ligands containing a hydrophilic carboxylic group, which makes the complexes soluble in an aqueous medium. The hydrolytic stability of the clusters’ aqueous solutions allows us to investigate for the first time the influence of W6-clusters on cell viability. The results obtained clearly demonstrate their very low cytotoxicity, comparable to the least-toxic clusters presented in the literature.

A series of cadmium(II) coordination compounds with bis(benzimidazol-2-yl)methane (L) is synthesized. Single crystals are obtained, and molecular and crystal structures of [Cd4(L)4Cl6(EtOH)0.77(H2O)1.23] [CdCl4]·H2O·5EtOH, [Cd(L)I2], and [Cd(L)2(EtOH)2][Cd(L)(NO3)3]2·6EtOH complexes are determined. According to the single crystal X-ray diffraction analysis, the organic ligand has a bidentate cyclic coordination. Distinctions in the structures of the compounds depending on the anion present are observed. The [Cd(L)I2] complex is mononuclear with cadmium ions are in the tetrahedral environment. Cadmium chloride and nitrate complexes are cationic-anionic with cadmium ions in different environments, and their coordination numbers vary in the range of 4-7.

A new approach is suggested herein for the synthesis of pyrazole derivatives by reacting 4-nitrosemicarbazide with acetylacetone. Additional studies were done on the reaction of acetylacetone with semicarbazide and its derivatives (4-aminosemicarbazide, methylsemicarbazide, and dimethylsemicarbazide). The study on the reaction with acetylacetone resulted in monocyclic 3,5-dimethyl-N-nitropyrazole-1-carboxamide, monocyclic 5-hydroxy-3,5-dimethyl-2-pyrazoline, and bicyclic bis(3,5-dimethylpyrazole-1-carbonyl)hydrazine, and conditions for the formation of acetone semicarbazone were identified. The structures of the resultant compounds were validated by physicochemical analytical methods, including X-ray diffraction. The computer-aided screening in the PASS prediction software discovered a high biological activity of the newly obtained compounds.

[Cu(L)2] (1), [Co(L)2] (2), [Ni(L)2]·H2O (3) complexes where L is 2-{[(2-methoxyphenyl)amino]methylene}-5,5-dimethyl-cyclohexane-1,3-dionate are synthesized. Single crystals of complexes 1-3 are obtained. According to X-ray crystallographic data, in the Co and Ni complexes, a coordination polyhedron N2O4 is a distorted octahedron, and in the Cu complex, N2O2 is a distorted square. L is a tridentate ligand coordinated by oxygen atoms of carbonyl and methoxy groups as well as the nitrogen atom of the amide group. The cytotoxic properties of 2-{[(2-methoxyphenyl)amino]methylene}-5,5-dimethyl-cyclohexane-1,3-dione and respective complexes are studied on the Hep2 cell line (human laryngeal carcinoma). The compounds are shown to not exhibit cytotoxic properties in the studied concentration range (1-50 μM). Antibacterial, protistocidal, and fungistatic properties of HL, its structural analogue 2-anilinomethylidene-5,5-dimethylcyclohexane-1,3-dione (HL1), and complexes on their base are also studied. The antibacterial activity of HL and [Co(L1)2(C2H5OH)2] against S. aureus, of HL1 and [Co(L)2] against E. coli is revealed within 25-30% of the activity of reference drugs (ciprofloxacin, furazolidone). The [Ni(L1)2(C2H5OH)2] complex is found to have a pronounced protistocidal activity. Furthermore, the behavior of the [Ni(L)2]·H2O complex in phosphate buffered saline is analyzed at storage times t = 0 h, 24 h, 48 h and also in an aqueous solution at different pH values.

The paper demonstrates a “greener” oxidation of dextran polymer of various molecular masses, the component of many industrially and pharmaceutically important materials, by aqueous H2O2 in a no cat...

Pyrrolidine nitroxides with four bulky alkyl substituents adjacent to N-O group are known for their high resistance to bioreduction. The 3,4-unsubstituted 2

The family of chalcogenide molybdenum clusters is well presented in the literature by a series of compounds of nuclearity ranging from binuclear to multinuclear articulating octahedral fragments. Clusters actively studied in the last decades were shown to be promising as components of superconducting, magnetic, and catalytic systems. Here, we report the synthesis and detailed characterization of new and unusual representatives of chalcogenide clusters: square pyramidal complexes [{Mo5(μ3-Se)i4(μ4-Se)i(μ-pz)i4}(pzH)t5]1+/2+ (pzH = pyrazole, i = inner, t = terminal). Individually obtained oxidized (2+) and reduced (1+) forms have very close geometry (proven by single-crystal X-ray diffraction analysis) and are able to reversibly transform into each other, which was confirmed by cyclic voltammetry. Comprehensive characterization of the complexes, both in solid and in solution, confirms the different charge state of molybdenum in clusters (XPS), magnetic properties (EPR), and so on. DFT calculations complement the diverse study of new complexes, expanding the chemistry of molybdenum chalcogenide clusters.

Activation of a hydroxyl group towards nucleophilic substitution via reaction with methanesulfonyl chloride or PPh3-CBr4 system is a commonly used pathway to various functional derivatives. The reactions of (5R(S),6R(S))-1-X-6-(hydroxymethyl)-2,2-dimethyl- 1-azaspiro[4.4]nonanes 1a–d (X = O·, H, OBn, OBz) with MsCl/NR3 or PPh3-CBr4 were studied. Depending on substituent X, the reaction afforded hexahydro-1H,6H-cyclopenta[c]pyrrolo[1,2-b]isoxazole (2) (for X = O), a mixture of 2 and octahydrocyclopenta[c]azepines (4–6) (for X = OBn, OBz), or perhydro-cyclopenta[2,3]azeto[1,2-a]pyrrol (3) (for X = H) derivatives. Alkylation of the latter with MeI with subsequent Hofmann elimination afforded 2,3,3-trimethyl-1,2,3,4,5,7,8,8a-octahydrocyclopenta[c]azepine with 56% yield.

By the interaction of Nb(NMe2)5 and 1,3-(2,6-diisopropylphenyl)imidazolium (IPr·HBF4) tetrafluoroborate a binuclear complex with coordinated N-heterocyclic carbene [(IPr)Nb(=NMe)(NMe2)(μ-F)2(μ-NMe2) NbF2(NMe2)] (1) is obtained. The reaction of Nb(NMe2)5 and 1,3-(2,4,6-trimethylphenyl)imidazolium (IMes·HBF4) tetrafluoroborate yields [(IMes)2H][NbF6] salt (2). The structure of the complexes is determined by single crystal X-ray diffraction.

Reactions of [{Re6Q8}Br6]4−/3− (Q = S, Se) with molten imidazole lead to the formation of two new neutral cluster complexes [{Re6Q8}(imzH)4(imz)2] (imzH = imidazole). The interaction of [{Re6Q8}(imzH)4(imz)2] with hydrohalic acids resulted in cationic complexes [{Re6Q8}(imzH)6]X2 (X = Cl, Br). All compounds were characterised by X-ray single-crystal and powder diffraction analyses, elemental analysis, energy dispersive X-ray and IR spectroscopies. The luminescence of the neutral compounds [{Re6Q8}(imzH)4(imz)2] was also studied.

Methylation of anionic cluster complexes [Re6Q8(CN)6]4− with ((CH3)3O)BF4 or CF3SO3CH3 afforded homoleptic isonitrile cluster complexes [Re6Q8(CH3NC)6]2+ (Q = S, Se, Te). The clusters were characterized by X-ray crystallography, mass spectrometry, 1H NMR, 13C NMR, 14N NMR, 15N NMR, 77Se NMR, and 125Te NMR techniques, electrochemistry, TGA, and photophysical measurements.

It has been established that ethyl iodoacelate and 1,4-diiodobutane alkylate triarylantimony Ar3Sb with the formation of [Ar3SbCH2C(O)OEt]+I− and [Ar3Sb(CH2)4I]+I−, \({[{\rm{A}}{{\rm{r}}_3}{\rm{Sb}}{({\rm{C}}{{\rm{H}}_2})_4}{\rm{I}}]^ + }{{\rm{I}}^ - },\;{[{\rm{A}}{{\rm{r}}_3}{\rm{Sb}}{({\rm{C}}{{\rm{H}}_2})_4}{\rm{SbA}}{{\rm{r}}_3}]^ {2+} }{\rm{I}}_2^ - \), where Ar = 2,6-(OMe)2C6H3. The complexes \([{\rm{A}}{{\rm{r}}_3}{\rm{SbC}}{{\rm{H}}_2}{\rm{C}}({\rm{O}}){\rm{OEt}}]_2^ + \;{[{\rm{H}}{{\rm{g}}_2}{{\rm{I}}_6}]^{2 - }}\) and \([{\rm{A}}{{\rm{r}}_3}{\rm{SbMe}}]_2^ + \;{[{\rm{Hg}}{{\rm{I}}_4}]^{2 - }}\) · DMSO have been synthesized by the reaction of [Ar3SbCH2C(O)OEt]+I− and [Ar3SbMe]+I− with mercury diiodide and studied by X-ray diffraction. The antimony and iodine atoms have a distorted tetrahedral coordination. The CSbC and IHgI angles are ranged within 103.28(14)°–116.68(14)°, 103.7(4)°–115.5(4)° and 98.122(9)°–125.590(12)°, 102.66(2)°–115.64(2)°, respectively.

Potato starch is one of the most important renewable sources for industrial manufacturing of organic compounds. Currently, it is produced from mixed potato varieties that often are harvested from different fields. Meanwhile, tuber starches of various potato breeds differ in their crystallinity, granule morphology, and other physical and chemical parameters. We studied the reactions of raw potato starches of different origins to chemical and biochemical reactions typically used for industrial starch modification. The results clearly demonstrate that there is a significant difference in the reactivity of the starches of different potato genotypes. While the main products of the transformations are the same, their preparative yields differ significantly. Thus, tuber starch of certain potato varieties may be more suitable for specific industrial purposes. Starch reactivity may potentially be a phenotypical trait for potato breeding to obtain potato starches for various industrial applications.

This work presents the design and synthesis of camphor, fenchone, and norcamphor N-acylhydrazone derivatives as a new class of inhibitors of the Hantaan virus, which causes haemorrhagic fever with renal syndrome (HFRS). A cytopathic model was developed for testing chemotherapeutics against the Hantaan virus, strain 76–118. In addition, a study of the antiviral activity was carried out using a pseudoviral system. It was found that the hit compound possesses significant activity (IC50 = 7.6 ± 2 µM) along with low toxicity (CC50 > 1000 µM). Using molecular docking procedures, the binding with Hantavirus nucleoprotein was evaluated and the correlation between the structure of the synthesised compounds and the antiviral activity was established.

Compounds based on new cyanide cluster anions [{Mo6I8}(CN)6]2&ndash, trans-[{Mo6I8}(CN)4(MeO)2]2&ndash, and trans-[{W6I8}(CN)2(MeO)4]2&minus, were synthesized using mechanochemical or solvothermal synthesis. The crystal and electronic structures as well as spectroscopic properties of the anions were investigated. It was found that the new compounds exhibit red luminescence upon excitation by UV light in the solid state and solutions, as other cluster complexes based on {Mo6I8}4+ and {W6I8}4+ cores do. The compounds can be recrystallized from aqueous methanol solutions, besides this, it was shown using NMR and UV-Vis spectroscopy that anions did not undergo hydrolysis in the solutions for a long time. These facts indicate that hydrolytic stabilization of {Mo6I8} and {W6I8} cluster cores can be achieved by coordination of cyanide ligands.

Interaction of the tetradentate redox-active 6,6'-[1,2-phenylenebis(azanediyl)]bis(2,4-di-tert-butylphenol) (H4 L) with TeCl4 leads to neutral diamagnetic compound TeL (1) in high yield. The molecule of 1 has a nearly planar TeN2 O2 fragment, which suggests the formulation of 1 as TeII L2- , in agreement with the results of DFT calculations and QTAIM and NBO analyses. Reduction of 1 with one equivalent of [CoCp2 ] leads to quantitative formation of the paramagnetic salt [CoCp2 ]+ [1].- , which was characterised by single-crystal XRD. The solution EPR spectrum of [CoCp2 ]+ [1].- at room temperature features a quintet due to splitting on two equivalent 14 N nuclei. Below 150 K it turns into a broad singlet line with two weak satellites due to the splitting on the 125 Te nucleus. Two-component relativistic DFT calculations perfectly reproduce the a(14 N) HFI constants and A∥ (125 Te) value responsible for the low-temperature satellite splitting. Calculations predict that the additional electron in 1.- is localised mainly on L, while the spin density is delocalised over the whole molecule with significant localisation on the Te atom (≥30 %). All these data suggest that 1.- can be regarded as the first example of a structurally characterised monomeric tellurium-nitrogen radical anion.

Here we explore the effect of the nature of organic ligands in rhenium cluster complexes [Re6 Q8 L6 ]4- (where Q=S or Se, and L=benzotriazole, 1,2,3-triazole or 1,2,4-triazole) on the biological properties of the complexes, in particular on the cellular toxicity, cellular internalization and localization. Specifically, the study describes the synthesis and detailed characterization of the structure, luminescence and electrochemical properties of the four new Re6 clusters with 1,2,3- and 1,2,4-triazoles. Biological assays of these complexes are also discussed in addition to those with benzotriazole using cervical cancer (HeLa) and immortalized human fibroblasts (CRL-4025) as model cell lines. Our study demonstrates that the presence of hydrophobic and π-bonding rich units such as the benzene ring in benzotriazole significantly enhances cellular internalization of rhenium clusters. These ligands facilitate binding of the clusters to DNA, which results in increased cytotoxicity of the complexes.

Octahedral molybdenum and tungsten clusters have potential biological applications in photodynamic therapy and bioimaging. However, poor solubility and hydrolysis stability of these compounds hinder their application. The first water-soluble photoluminescent octahedral tungsten cluster [{W6 I8 }(DMSO)6 ](NO3 )4 was synthesised and demonstrated to be at least one order of magnitude more stable towards hydrolysis than its molybdenum analogue. Biological studies of the compound on larynx carcinoma cells suggest that it has a significant photoinduced toxicity, while the dark toxicity increases with the increase of the degree of hydrolysis. The increase of the dark toxicity is associated with the in situ generation of nanoparticles that clog up the cisternae of rough endoplasmic reticulum.

A convenient and efficient method for the synthesis of polyfluorinated 2-mercaptobenzothiazoles from the corresponding aniline derivatives and CS2, mediated by 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) in toluene is described. The reaction proceeded via nucleophilic attack at the carbon atom of carbon disulfide by the nitrogen atom of NH2-group in arene followed by selective intramolecular fluorine atom substitution in the ortho-position to the amino group. This synthetic methodology could be used to prepare fluorinated 2-mercaptobenzothiazole containing alkynyl group in good to excellent yields. The reaction takes place under very mild reaction conditions (50 °C) and uses readily available starting materials.

Reaction of [Cp'2ZrMe2] (Cp' = η5-tBuC5H4) with 3,6-di-tert-butylcatechol (H2Cat36) leads to complex [Cp'2ZrCat36] (1). Analogous reaction of [Cp'2ZrMe2] with 3,6-di-tert-butyl-o-benzoquinone (Q36) results in migration of the methyl group from metal to the C6-ring and formation of a complex of 3-tert-butyl-6-methyl-catecholate [Cp'2ZrCat36Me] (2). Both products were characterized with single crystal X-ray diffraction and NMR spectroscopy.

(Bu4N)2[Mo6I8(N3)6] undergoes [3+2] cycloaddition with benzonitrile or 2,3,4,5,6-pentafluorobenzonitrile in the presence of I2 catalyst with the formation of novel hexakis(tetrazolate)complexes, (Bu4N)2[Mo6I8(N4C-Ar)6] (Ar = C6H5 (1), C6F5 (2)) with coordinated 2,5-tetrazolyl ligands. The products were characterized by X-ray analysis, NMR, IR and ESI-mass spectrometry. The complexes undergo quasi reversible oxidation and are red-light emissive upon UV photoexcitation.

In this work, a water-soluble supramolecular complex was synthesized in an aqueous suspension of betulin diacetate (BDA) and arabinogalactan (AG) upon microwave heating. Microwave heating allows reducing the time required for the complex formation, compared with conventional heating in a water bath. The specific effect of microwave irradiation on the initial reagents and preparation of a supramolecular complex was studied. In contrast to conventional heating, under microwave heating AG macromolecules may break into roughly equal fragments when the temperature increases up to 100 °C. A change in the surface morphology of BDA crystals under microwave heating of the suspension suggests that microwave irradiation facilitates the dissolution of BDA in water. It has been shown that the use of dimethylsulfoxide as a reaction medium for microwave heating led to a decrease in BDA content in the product due to the inclusion of DMSO into AG macromolecules. The BDA–AG complex was isolated from the microwave-heated aqueous solution, after water evaporation, as a thin amorphous film, which exhibited antitumor activity against Ehrlich ascites carcinoma cells and can be a promising material for pharmacological applications.

A tert-BuOOH/Fe(II) system is used for the free radical substitution of the chlorine atom at the rib of a boron capped iron(II) tris-dioximate chlathrochelate for 1,3,5-trioxane. The structure of the compound is determined by single crystal XRD and solution NMR.

The reaction of LaCl3 with s-diketoimine potassium salt KDipp,MeNacnac (KL) affords the molecular complex [LaLL'] with singly and doubly deprotonated diketoimine. The complex is characterized by single- crystal X-ray diffraction analysis (CIF file CCDC 1528658). The structure of [LaLL'] in solution is studied by 1D and 2D 1H and 13C NMR spectroscopy.