The thermodynamic characteristics of solution of acetoacetyl- and 1,1′-<Emphasis Type="Italic">bis</Emphasis>-(acetoacetyl)ferrocene in water-propanol and water-isopropanol mixtures

The polythermal solubility of acetoacetylferrocene and 1,1′-bis-(acetoacetyl)ferrocene in water-propanol and water-isopropanol solvents of various compositions was studied. The solubility of both derivatives increased as the contents of the alcohols grew, to a slightly greater extent for acetoacetylferrocene than for 1,1′-bis-(acetoacetyl)ferrocene. The solubilities of the same compounds in water-propanol and water-isopropanol mixtures at equal alcohol contents were almost equal. An analysis of the logarithmic dependences of solubility on the molar concentration of the alcohols led us to suggest two solubility mechanisms, cavity and solvation. The thermodynamic characteristics of solution calculated from the temperature dependences of solubility substantiate this suggestion.     

Crystal structure of the molecular complex of 1,3,5-<Emphasis Type="Italic">tris</Emphasis>-<Emphasis Type="Italic">m</Emphasis>-chlorophenylisocyanurate with ε-caprolactone

The molecular complexes of 1,3,5-tris-m-chlorophenylisocyanurate and ε-caprolactone were synthesized by the reaction of the latter with 3-chlorophenylisocyanate in the presence of triethylamine. Single crystals were grown, and the molecular and crystal structures of the synthesized complexes were investigated.     

<Emphasis Type="Italic">N</Emphasis>-arylsulfanyl-<Emphasis Type="Italic">N</Emphasis>-arylsulfonyl(acyl)-<Emphasis Type="Italic">N</Emphasis>′-phenylthiourea sodium salts

Reactions of N-arylsulfonyl(acyl)arenesulfenamide sodium salts with phenyl isothiocyanate afforded N-arylsulfanyl-N-arylsulfonyl(acyl)-N-phenylthioura sodium salts which were found to increase thermal stability of finely dispersed poly(vinyl chloride).Translated from Zhurnal Organicheskoi Khimii, Vol. 40, No. 10, 2004, pp. 1532–1535.Original Russian Text Copyright © 2004 by Koval, Oleinik.     

Physicochemical properties and complexing ability of <Emphasis Type="Italic">N</Emphasis>-(2-ethylhexanoyl)-<Emphasis Type="Italic">N</Emphasis>′-sulfonylhydrazines

The effect of substituent at the sulfonyl group on the physicochemical properties and complexing ability of the sulfonyl derivatives of 2-ethylhexanoic acid hydrazide of the general formula C₄H₉CH(C₂H₅)C(O)·NHNHSO₂C₆H₅R [R = H, CH₃, NO₂, NHC(O)CH₃, Cl] with respect to Cu(II), Co(II), and Ni(II) ions was studied.     

Cyclization of the substituted <Emphasis Type="Italic">N</Emphasis>-(<Emphasis Type="Italic">Ortho</Emphasis>-cyclopropylphenyl)-<Emphasis Type="Italic">N′</Emphasis>-aryl ureas and thioureas in the gas phase and solution

Electron ionization (EI), chemical ionization (CI), tandem mass spectrometry, high-resolution measurements, and labeling studies as well as quantum chemical calculations were used to understand the behavior of the molecular radical cations (EI) and protonated molecules (CI) of substituted N-(ortho-cyclopropylphenyl)-N'-aryl ureas and N-(ortho-cyclopropylphenyl)-N'-aryl thioureas in a mass spectrometer. Fragmentation schemes and possible mechanisms of primary isomerization were proposed. According to the fragmentation pattern, formation of the corresponding benzoxazines and benzothiazines was considered as the major process of isomerization of the original M(+.) and MH(+), although some portions of these ions definitely transformed into other structures. The treatment of N-(ortho-cyclopropylphenyl)-N'-phenyl urea and N-(ortho-cyclopropylphenyl)-N'-phenylthiourea in solution with strong acids formed predicted 4-ethyl-N-phenyl-4H-3,1-benzoxazin-2-amin and 4-ethyl-N-phenyl-4H-3,1-benzothiazin-2-amine as principal products.     

Structural and crystal chemistry analysis of (4<Emphasis Type="Italic">E</Emphasis>)- and (4<Emphasis Type="Italic">Z</Emphasis>)-6,6′,7,7′-tetrahydro-5H,5′H-4,4′-<Emphasis Type="Italic">bis</Emphasis>-1-benzothiophenes

(4E)-6,6′,7,7′-tetrahydro-5H,5′H-4,4′-bis-1-benzothiophene and (4Z)-6,6′,7,7′-tetrahydro-5H,5′H-4,4′-bis-1-benzothiophene are studied by means of X-ray diffraction. The intermolecular interaction energy is calculated and the structural subclass of each compound is derived. These compounds have been found to have similar full crystal energies and packing efficiencies. The observed pseudosymmetry effects are described.     

Synthesis and characteristics of <Emphasis Type="Italic">N</Emphasis>-(glyoxyldioxime)-<Emphasis Type="Italic">N</Emphasis>′-(2-hydroxybenzylidene)-1,4-diaminonaphthalene and its metal complexes

A new vic-dioxime, N-(glyoxyldioxime)-N′-(2-hydroxybenzylidene)-1,4-diaminonaphthalene, was synthesized proceeding from naphthalene. Its complexes of nickel, copper and cobalt were prepared. The vicdioxime and its complexes were charecterized by FT-IR, UV, ¹H NMR, mass spectrometry, elemental analysis, DTA/TG analysis techniques and conductometric measurements. Published in Russian in Zhurnal Obshchei Khimii, 2008, Vol. 78, No. 5, pp. 797–802. The text was submitted by authors in English.     

Synthesis of <Emphasis Type="Italic">N</Emphasis>-nitro-<Emphasis Type="Italic">N</Emphasis>′-(trimethylsilyl)carbodiimide

Nitration of N,N′-bis(trimethylsilyl)carbodiimide with N₂O₅ or (NO₂)₂SiF₆ afforded N-nitro-N´-(trimethylsilyl)carbodiimide, the first representative of N-nitro carbodiimides. Its further nitration led to the release of CO₂, which is presumably formed in the course of N,N´-dinitrocarbodiimide decomposition. The reactions of N-nitro-N´-(trimethylsilyl)carbodiimide with nucleophiles take place both at the tri methylsilyl group (for example, with NH₃) to give nitrocyanamide salts and at the carbodiimide C atom (for example, with Et₂NH) to give the corresponding nitroguan idines.     

Synthesis of imidazo[4,5-<Emphasis Type="Italic">e</Emphasis>]benzo[1,2-<Emphasis Type="Italic">c</Emphasis>;3,4-<Emphasis Type="Italic">c</Emphasis>´]difuroxanes

A method for the synthesis of imidazo[4,5-e]benzo[1,2-c;3,4-c´]difuroxanes, potential nitric oxide donors, has been developed. The synthesized compounds were characterized by IR and NMR spectroscopy, high resolution mass spectrometry, and elemental analysis.     

Synthesis and reactivity of 2-(2-furyl)-1,7-dimethyl-1<Emphasis Type="Italic">H</Emphasis>,7<Emphasis Type="Italic">H</Emphasis>-benzo[1,2-<Emphasis Type="Italic">d</Emphasis>: 3,4-<Emphasis Type="Italic">d</Emphasis>′]diimidazole

2-(2-Furyl)-1,7-dimethyl-1H,7H-benzo[1,2-d: 3,4-d′]diimidazole was synthesized by the Weidenhagen reaction followed by N-methylation. Electrophilic substitution reactions of the title compound (nitration, bromination, sulfonation, formylation, and acylation) involved both the furan ring and central benzene fragment.     

1,3-Diamino-2-Hydroxypropane-<Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>′,<Emphasis Type="Italic">N</Emphasis>′-Tetraacetic Acid: Crystal and Molecular Structures

The synthesis, IR spectroscopic study, and X-ray diffraction analysis (CIF file CCDC no. 1574078) are carried out for 1,3-diamino-2-hydroxypropane-N,N,N′,N′-tetraacetic acid (I). The structural units of a crystal of compound I are (H_4.5HPdta)^0.5– anions, (H_5.5HPdta)^0.5+ cations, and molecules of water of crystallization joined by a branched network of hydrogen bonds: strong intermolecular O–H…O and intramolecular N–H…O bonds.     

Crystal and molecular structure of (±)-2-[(1<Emphasis Type="Italic">S</Emphasis>,3<Emphasis Type="Italic">S</Emphasis>)-3-acetyl-2,2-dimethylcyclobutyl]-N-(<Emphasis Type="Italic">p</Emphasis>-tolyl)acetamide

The structure of (±)-2-[(1S,3S)-3-acetyl-2,2-dimethylcyclobutyl]-N-(p-tolyl)acetamide has been determined by single crystal X-ray diffraction analysis. The crystal belongs to triclinic system, space group P-1, a = 8.8700(18) Å, b = 10.331(2) Å, c = 10.363(2) Å, α = 71.11(3)°, β = 65.06(3)°, γ = 72.18(3)°, V = 798.6(3) ų, Z = 2, formula unit C₁₇H₂₃NO₂. The title compound has a fragment of 2,2-dimethylcyclo-butane and its conformation represents semi-chair. The intermolecular hydrogen bonds N-H...O and C-H...O are revealed.     

X-ray and computational structural study of neutral <Emphasis Type="Italic">bis</Emphasis>(<Emphasis Type="Italic">N,N,N</Emphasis>′,<Emphasis Type="Italic">N</Emphasis>′-tetramethylthiophosphoramidoyl)-methylamine

The structure of bis(N,N,N′,N′-tetramethylthiophosphoramidoyl)-methylamine 1 has been determined by single-crystal X-ray diffraction. The compound 1 crystallizes in the monoclinic system, with a space group P2₁/c, a = 11.836(2) Å, b = 11.659(2) Å, c = 12.796(5) Å and β = 95.28(3)°, V = 1758.3(5) Å³ and Z = 4. The X-ray crystallographic data have been assessed by semi-empirical and ab-initio density functional theory and by Hartree–Fock molecular orbital methods. A comparative study of the results of the different methods is given.     

Preparation of surfactant-free nanoparticles of methoxy poly(ethylene glycol)-<Emphasis Type="Italic">b</Emphasis>-poly(D,L-lactide-<Emphasis Type="Italic">co</Emphasis>-glycolide-<Emphasis Type="Italic">co</Emphasis>-ɛ-caprolactone)

Surfactant-free nanoparticles of methoxy poly(ethylene glycol)-b-poly(D,L-lactide-co-glycolide-co-ɛ-caprolactone) diblock copolymers (MPEG-b-PDLLGCL) with different DLL:G:CL ratios were prepared by modified-spontaneous emulsification solvent diffusion method. Sizes of resulted colloidal nanoparticles obtained from light-scattering analysis were in the range of 121–132 nm with narrow size distribution. The nanoparticle sizes depended on the composition of the PDLLGCL block. Scanning electron microscopy demonstrated that the nanoparticles were aggregated after drying process, suggested they were soft nanoparticles. However, their initial aggregates can be observed and it was shown that the nanoparticles have spherical shape with smooth surface. The text was submitted by the authors in English.     

Synthesis and structure of the cobalt(II) coordination compounds with <Emphasis Type="Italic">N,N</Emphasis>-dimethyl-<Emphasis Type="Italic">N</Emphasis>′,<Emphasis Type="Italic">N</Emphasis>′-dimethylthiocarbamoylsulfenamide

The CoLX₂ complexes were obtained by the reaction of N,N-dimethyl-N′,N′-dimethylthio-carbamoylsulfenamide (L) with CoX₂ (X = Cl, Br, I, NCS). The complexes were investigated by elemental and X-ray analysis, IR, ¹H NMR, and electron spectroscopy, conductometry, magnetochemistry, thermogravimetry. It is found that these compounds are high-spin complexes of pseudotetraedral structure with bidentate coordination of L through the thione sulfur atom and sulfenamide nitrogen atom.     

Properties of a poly(ethylene glycol)-<Emphasis Type="Italic">block</Emphasis>-poly(<Emphasis Type="Italic">γ</Emphasis>-benzyl <Emphasis Type="SmallCaps">l</Emphasis>-glutamate)-<Emphasis Type="Italic">graft</Emphasis>-poly(ethylene glycol) copolymer membrane

Poly(ethylene glycol)-block-poly(γ-benzyl l-glutamate)-graft-poly(ethylene glycol) (PEG-block-PBLG-graft-PEG) copolymer was synthesized by the ester exchange reaction of PBLG-block-PEG copolymer with a PEG chain. Surface morphology of the PEG-block-PBLG-graft-PEG copolymer membrane was characterized by atomic force microscopy (AFM). Mechanical and chemical properties of the PEG-block-PBLG-graft-PEG copolymer membrane were investigated by tensile testing and contact angle testing. The effects of grafting ratio on the properties of PEG-block-PBLG-graft-PEG copolymer membrane were primarilly studied.     

Synthesis and antibacterial and antifungal activities of <Emphasis Type="Italic">N</Emphasis>-(tetra-<Emphasis Type="Italic">O</Emphasis>-acetyl-β-<Emphasis Type="SmallCaps">d</Emphasis>-glucopyranosyl)thiosemicarbazones of substituted 4-formylsydnones

Background

Sydnone is a heterocycle that exhibits remarkable pharmacological activities, including antimicrobial, anti-inflammatory, analgesic, antipyretic and antioxidant activities. Thiosemicarbazones are of compounds that contain the –NHCSNHN=C< linkage group and are considerable interest because they exhibit important chemical properties and potentially beneficial biological activities. Similarly, thiosemicarbazones having carbohydrate moieties also exhibit various significant biological activities.

Results

The compounds of 3-formyl-4-phenylsydnones were obtained by Vilsmeyer-Haack’s formylation reaction and were transformed into thiosemicarbazones by condensation reaction with N-(2,3,4,6-tetra-O-acetyl-β-d-glucopyranosyl)thiosemicarbazide. Reaction were performed in the presence glacial acetic acid as catalyst using microwave-assisted heating method. Reaction yields were 43?85 %. The antimicrobial activities of these thiosemicarbazones were screened in vitro by using agar well diffusion and MIC methods. Among these thiosemicarbazones, compounds 4k, 4l, 4m and 4n were more active against all tested bacterial strains, especially against S. epidermidis, B. subtilis and E. coli. The MIC values in these cases are 0.156, 0.156 and 0.313 μg/mL, respectively. All compounds showed weak to moderate antifungal activity against C. albicans and A. niger than nystatin (MIC = 0.156?0.625 μg/mL vs. MIC = 0.078 μg/mL of nystatin), and thiosemicarbazones 4l, 4m and 4n exhibited significant activity with MIC = 0.156 μg/mL. These compounds also had good antifungal activity against F. oxysporum similarly to nystatin (MIC = 0.156 μg/mL). Among the tested compounds having halogen group 4k, 4l, 4m and 4n showed highest activity against three strains of fungal organisms.

Conclusions

In summary, we have developed a clean and efficient methodology for the synthesis of novel thiosemicarbazone derivatives bearing sydnone ring and d-glucose moiety; the heterocyclic and monosaccharide system being connected via ?NH?C(=S)NH?N=C< linker using molecular modification approach. The methodology could be further extended and used for the synthesis of other thiosemicarbazones of biological importance. 4-Formyl-3-arylsydnone N-(2,3,4,6-tetra-O-acetyl-β-d-glucopyranosyl)thiosemicarbazones have been synthesized under microwave-assisted heating conditions. Almost all obtained compounds showed remarkable activities against the tested microorganisms. Among the tested compounds having halogen group 4k, 4l, 4m and 4n showed highest activity against all tested strains of bacterial and fungal organisms.

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Graphical abstract:Synthesis and antibacterial and antifungal activities of N-(tetra-O-acetyl-β-D-glucopyranosyl)thiosemicarbazones of substituted 4-formylsydnones

     

Characteristics of the hydrogen bond and the structure of Н-complexes of <Emphasis Type="Italic">p</Emphasis>-n-propyloxybenzoic acid and <Emphasis Type="Italic">p</Emphasis>-n-propyloxy-<Emphasis Type="Italic">p</Emphasis>′-cyanobiphenyl

The conformational properties of p-n-propyloxybenzoic acid and p-n-propyloxy-p′-cyanobiphenyl molecules, which can exhibit liquid crystalline properties in the formation of Н-complexes, are studied (DFT/B3LYP)/cc-pVTZ method). It is found that a molecule of p-n-propyloxybenzoic acid has 16 conformers that can be divided into four groups with respect to relative energies (0 kcal/mol, 1.6 kcal/mol, 6.5 kcal/mol, and 8.1 kcal/mol), and a molecule of p-n-propyloxy-p′-cyanobiphenyl has six conformers with relative energies of 0 kcal/mol (two conformers, φ(С_Ph–O–C–C)=180°) and 1.6 kcal/mol (four conformers, φ(С_Ph–O–C–C)=64.4°). In all conformers of the 3-AOCB molecule, phenyl rings are turned at 35° relative to each other. A conformation with the planar arrangement of two rings has a higher energy by 1.5 kcal/mol. Barriers to the internal rotation of different groups are determined and it is established that the structural nonrigidity of the molecules is mainly due to the possible rotation of the–C₂Н₅ moiety about the C–C bond. It is shown that with increasing temperature the vibrational amplitudes of the OC₃H₇ substituent, which enhance the probabilities of transitions between the conformers, become appreciably larger. It is found that p-n-propyloxybenzoic acid and p-n-propyloxy-p′-cyanobiphenyl can form Н-complexes with the medium hydrogen bond. Two types of the structural organization of Н-complexes are considered: linear and angular. The similarity of energies of Н-complexes with different structures (NBO analysis) can be the reason for the occurrence of two liquid crystalline subphases of p-n-propyloxybenzoic acid and p-n-propyloxy-p′-cyanobiphenyl system.     

Thermal studies of Co(II), Ni(II) and Cu(II) complexes of N,N′-<Emphasis Type="Italic">bis</Emphasis>(3,5-Di-<Emphasis Type="Italic">t</Emphasis>-butylsalicylidene)ethylenediamine

The thermal decomposition kinetics of sterically hindered salen type ligand (L) and its metal complexes [M=Co(II), Ni(II), Cu(II)] were investigated by thermogravimetric analysis. A direct insertion probe-mass spectrometer (DIP-MS) was used for the characterization of metal complexes of L and all fragmentations and stable ions were characterized. The thermogravimetry and differential thermogravimetry (TG-DTG) plots of salen type salicylaldimine ligand and complexes showed a single step. The kinetic analysis of thermogravimetric data was performed by using the invariant kinetic parameter method (IKP). The values of the invariant activation energy, E _inv and the invariant pre-exponential factor, A _inv, were calculated by using Coats-Redfern (CR) method. The thermal stabilities and activation energies of metal complexes of sterically hindered salen type ligand (L) were found as Co(II)>Cu(II)>Ni(II)>L and E _Cu>E _Ni>E _Co>L. Also, the probabilities of decomposition functions were investigated. The diffusion functions (D _n) are most probable for the thermal decomposition of all complexes.     

Synthesis of New Thieno[2,3-<Emphasis Type="Italic">b</Emphasis>:5,4-<Emphasis Type="Italic">c</Emphasis>′]dipyridines

Summary. We describe the formation of thieno[2,3-b:5,4-c]dipyridines from 5,6-dihydropyridine-2(1H)-thiones. The two-step reaction mechanism was revealed by isolation of an intermediate. The oxo and thioxo groups of the obtained tricyclic compounds were hydrogenated selectively. The structures of all new compounds were elucidated by NMR experiments.Received December 17, 2002; accepted December 20, 2002 Published online June 2, 2003