Synthesis,structural, spectral,thermal and comparative biological activity studies of [V<Subscript>2</Subscript>O<Subscript>2</Subscript>(SO<Subscript>4</Subscript>)<Subscript>2</Subscript>(H<Subscript>2</Subscript>O)<Subscript>6</Subscript>]

The hydrothermal reaction of a mixture of V₂O₅, VCl₃, 2,5-pyridinedicarboxylic acid and diluted H₂SO₄ for 68 h at 180°C gives a blue colored solution which yields prismatic blue crystals of IV ₂ ^IV O₂(SO₄)₂(H₂O)₆] (1) in 32% yield (based on V). Complex 1 was investigated by means of elemental analysis (C, H and S), TGA, FT-IR, manganometric titration, Single Crystal X-ray Diffraction Methods and also comparative antimicrobial activities. Crystal data for the compound: monoclinic space group P2₁/c and unit cell parameters are a = 7.3850(12) Å, b = 7.3990(7) Å, c = 12.229(2) Å, β = 108.976(12)° and Z = 2. Although structure of 1 as a natural mineral has been previously determined, this work covers new preparation method and full characterization of 1 along with comparison of antibacterial activity between 1 and the commercial vanadium(IV) oxide sulfate hydrate compounds, VOSO₄ · xH₂O (Riedel-de Haën and Alfa Aesar brand names). 1 was evaluated for the antimicrobial activity against gram-positive, gram-negative bacteria, yeasts and mould compared with the commercial VOSO₄ · xH₂O compounds. 1 showed weak activity against bacteria Bacillus cereus, Nocardia asteroides and yeast Candida albicans. A good antimicrobial activity was recorded against Cirtobacter freundii (15 mm). There are only a few reproducible well-defined vanadium(IV) starting materials to use for exploring the synthesis of new materials. VCl₄, VO(acac)₂, VOSO₄ · xH₂O and [V(IV)OSO₄(H₂O)₄] · SO₄ · [H₂N(C₂H₄)₂NH₂] are common starting materials for such applications. In addition to these compounds, 1 can be used as an oxovanadium precursor.     

Spectroelectrochemical Study of 9‐Substituted Acridines with Potential Antitumor Activity

The electrochemical and spectroelectrochemical behavior of 9‐substituted with ? CN and ? COOH acridine N‐oxides with potential antitumor activity was investigated. In SER spectra of the investigated compounds, the ring stretching vibration at 1568 cm^?1 for 9‐CN‐substituted compound respectively 1639 cm^?1 for 9‐COOH‐substituted compound was analyzed. Cyclic voltammograms indicates that the reduction potential ?0.766 V for ? CN substituted compound increase towards ?0.745 V for ? COOH substituted compound. The proposed theoretical method in the electrochemical impedance spectroscopy uses a reference redox dielectrode and a multielectrode containing the compound. To account for the change of electrochemical impedance we have considered two theoretical quantities: a pseudocapacitance and a pseudo inductance. Two possible arrangements of them: in series, respective in parallel can be used like criteria of drug classification.     

Numerical modelling and simulation of Laviron treatment for poly-phenothiazine derivative-modified glassy carbon electrodes

Electropolymerization of a new phenothiazine derivative (bis-phenothiazin-3-yl methane, BPhM) on glassy carbon electrodes leads to electroactive and conducting layers of poly-BPhM. Based on the Laviron method, the kinetic parameters (the heterogeneous electron transfer rate constants k _s and transfer coefficients α) were calculated out of the experimental and theoretical data. The theoretical data have been obtained by using the analogical modelling and numerical simulating method. The modified electrodes present high values of k _s(~50s⁻¹) in phosphate buffer solutions of different pH values. A good correlation of mathematical and numerical simulated kinetic parameters has been obtained, with the experimental values and the norm of residuals being very close to zero.     

Synthesis and characterization of new polyfluorinated dendrimeric phthalocyanines

The synthesis of new polyfluorinated dendrimeric metallophthalocyanines (M = Zn, Ni, Co) bearing 3,5-bis(2′,3′,4′,5′,6′-pentafluorobenzyloxy)benzyloxy moieties (2–4) was achieved by cyclotetramerization of phthalonitrile derivative 1 in the presence of zinc, nickel or cobalt salts in DMF. All the target phthalocyanines were separated by column chromatography and their spectroscopic, fluorescence and energy transfer properties, and aggregation behavior were investigated in different solvents and at different concentrations in chloroform. The compounds were characterized by Fourier transform-infrared, fluorine, proton and carbon nuclear magnetic resonance, mass, ultraviolet–visible and fluorescence spectral data. The phthalocyanines (2–4) were extremely soluble in various organic solvents, such as tetrahydrofuran, acetone and dichloromethane.     

Complexation of metal ions with the novel azathia crown ethers carrying anthracene pendant in acetonitrile–dichloromethane

A series of crown ethers carrying an anthracene group with nitrogen–sulfur donor atom, which differ in having three, four and five sulfur atoms in the macrocycle was designed and synthesized by the reaction of the corresponding macrocyclic compound and 9-chloromethyl-anthracene. The influence of metal cations such as Al³⁺, Zn²⁺, Fe²⁺, Fe³⁺, Co²⁺, Ni²⁺, Mn²⁺, Cu²⁺, Cd²⁺, Hg²⁺ and Pb²⁺ on the spectroscopic properties of the ligands was investigated in acetonitrile–dichloromethane (1:1) by means of absorption and emission spectrometry. Absorption spectra show isosbestic points in the spectrophotometric titration of Al³⁺, Zn²⁺, Fe²⁺, Fe³⁺, Cu²⁺, Hg²⁺ and Pb²⁺ the results of which disclosed the complexation compositions and complex stability constants of the novel ligands with these cations. The monoazapentathia crown ether showed sensitivity for Al³⁺ with linear range and detection limit of 2.6 × 10⁻⁶ M–2.6 × 10⁻⁵ M and 8.1 × 10⁻⁷ M, respectively.     

Microwave-assisted and conventional synthesis and stereogenic properties of monospirocyclotriphosphazene derivatives

The reactions of hexachlorocyclotriphosphazene, N₃P₃Cl₆, with N/O donor type N-alkyl or (aryl)-o-hydroxybenzylamines HO(C₆H₄)CH₂NHR(Ar), [R(Ar) = C(CH₃)₃ (1), Ph (2)] produce monospirocyclic tetrachlorocyclotriphosphazenes (1a and 2a). The geminal substituted cyclotriphosphazenes (1b, 1d, 2b and 2d) are obtained from the reactions of 1 equiv. of 1a and 2a with 2 equiv. of pyrrolidine or morpholine in THF, while the fully substituted phosphazenes (1c, 1e, 2c and 2e) are formed from the reactions of 1a and 2a with the excess pyrrolidine or morpholine in toluene, between 24 and 48 h. The microwave-assisted reactions of 1a and 2a with excess pyrrolidine or morpholine in toluene afford the fully substituted products with higher yields than those which were obtained by conventional methods. The structural investigations of the compounds have been verified by elemental analyses, ESI-MS, FTIR, ¹H, ¹³C, ³¹P NMR and HETCOR techniques. The crystal structure of 2a is determined by X-ray crystallography and the phosphazene ring is in the flattened boat form. Compounds 1b, 1d, 2b and 2d in which the spiro aryloxy moiety provides the one centre of chirality exist as racemates and the chirality has been confirmed by ³¹P NMR spectroscopy on addition of a chiral solvating agent (CSA), (S)-(+)-2,2,2-trifluoro-1-(9′-anthryl)ethanol.     

Electrical and interface state density properties of polyaniline–poly-3-methyl thiophene blend/p-Si Schottky barrier diode

We have formed conjugated polymeric aniline–thiophene organic material on p-Si substrate by adding polyaniline–poly-3-methyl thiophene blend solution in acetonitrile on top of a p-Si substrate and then evaporating the solvent. It has been seen that the forward bias current–voltage (I–V) characteristics of polyaniline–poly-3-methyl thiophene blend/p-Si/Al with a barrier height value of 0.60 eV and an ideality factor value of 3.37 showed rectifying behaviour at room temperature. The polyaniline–poly-3-methyl thiophene blend/p-Si/Al Schottky barrier diode showed non-ideal I–V behaviour with the value of ideality factor greater than unity that could be ascribed to the interfacial layer, interface states and series resistance. Furthermore, Cheung's functions and modified Norde's function were used to extract the diode parameters including ideality factor, barrier height and series resistance. It has been seen that there is a good agreement between the barrier height values from all methods. However, the values of series resistance obtained from Cheung's functions is higher than the values obtained from Norde's functions. The energy distribution of interface states density, determined from forward bias current–voltage (I–V) characteristic technique at room temperature, increases exponentially with bias from 2.81 × 10¹⁶ cm^?2 eV^?1 in (0.73–E_v) eV to 1.14 × 10¹⁷ cm^?2 eV^?1 in (0.48–E_v) eV.     

Spectroscopic characterization of charge-transfer complexes of morpholine with chloranilic and picric acids in organic media: Crystal structure of bis(morpholinium 2,4,6-trinitrocyclohexanolate)

Electron donor–acceptor interaction of morpholine (morp) with chloranilic acid (cla) and picric acid (pa) as π-acceptors was investigated spectrophotometrically and found to form stable charge-transfer (CT) complexes (n–π*) of [(Hmorp)₂(cla)] and [(Hmorp)(pa)]₂. The donor site involved in CT interaction is morpholine nitrogen. These complexes are easily synthesized from the reaction of morp with cla and pa within MeOH and CHCl₃ solvents, respectively. ¹HNMR, IR, elemental analyses, and UV–vis techniques characterize the two morpholinium charge-transfer complexes. Benesi–Hildebrand and its modification methods were applied to the determination of association constant (K), molar extinction coefficient (?). The X-ray crystal structure was carried out for the interpretation the predict structure of the [(Hmorp)(pa)]₂ complex.     

In vivo biodistribution of <Superscript>131</Superscript>I labeled bleomycin (BLM) and isomers (A2 and B2) on experimental animal models

Bleomycins (BLMs; BLM, A2, and B2) were labeled with ¹³¹I and radiopharmaceutical potentials were investigated using animal models in this study. Quality control procedures were carried out using thin layer radiochromatography (TLRC), high performance liquid chromatography (HPLC), and liquid chromatography (LC/MS/MS). Labeling yields of radiolabeled BLMs were found to be 90, 68, and 71%, respectively. HPLC chromatograms were taken for BLM and cold iodinated BLM (¹²⁷I-BLM). Five peaks were detected for BLM and three peaks for ¹²⁷I-BLM in the HPLC studies. Two peaks belong to isomers of BLM. The isomers of BLM were purified with using HPLC. Biological activity of BLM was determined on male Albino Wistar rats by biodistribution and scintigraphic studies were performed for BLMs by using New Zelland rabbits. The biodistribution results of ¹³¹I-BLM showed high uptake in the stomach, the bladder, the prostate, the testicle, and the spinal cord in rats. Scintigraphic results on rabbits agrees with that of biodistributional studies on rats. The scintigraphy of radiolabeled isomers (¹³¹I-A2 and ¹³¹I-B2) are similiarly found with that of ¹³¹I-BLM.