Chromophore relaxation in a side-chain methacrylate copolymer functionalized with 4-[N-ethyl-N-(2-hydroxyethyl)]amino-2 '-chloro-4 '-nitroazobenzene

A side-chain methacrylate copolymer functionalized with the nonlinear optical chromophore 4-[N-ethyl-N-(2-hydroxyethyl)]amino-2'-chloro-4'-nitroazobenzene, disperse red-13, was prepared and characterized. The chromophore relaxation was investigated measuring the decay of the electrooptic coefficient r(13) and the complex dielectric constant at different temperatures. Results obtained below and above T-g were analyzed using the Kohlrausch-Williams-Watts(KWW) equation, through the study of the temperature dependence of the KWW parameters. Above T-g the relaxation time experimental data were fitted to the Williams-Landel-Ferry (WLF) equation and its parameters determined. Chromophore relaxation leading to the decrease of electrooptic properties was found associated with a primary alpha relaxation. The obtained WLF equation parameters were introduced into the Adam-Gibbs-Tool-Narayanaswamy-Moynihan equation, and the overall relaxation time temperature dependence was successfully obtained in terms of the fictive temperature, accounting for the sample thermal treatment and allowing optimized thermal treatment to be found. The copolymer KWW stretching parameter at the glass transition temperature lies close to the limit value for short-range interactions, i.e., 0.6, suggesting that the chromophore group is participating in primary a relaxation.

Nova rota de preparação do 2-cloro-1,3,2-dioxofosfolana e 2-cloro-4,5-benzo-1,3,2-dioxofosfolana e caracterização por espectroscopia de RMN multinuclear

A new method for the preparation of 2-chloro-1,3,2-dioxaphospholane (1) and 2-chloro-4,5-benzo-1,3,2-dioxaphospholane (2), are reported. The modifications introduced in the synthetic route improved the yield and facilitated the control of reaction, but the synthesis require longer reaction time. The compounds were characterized by ¹H, 13C{¹H} and31P{¹H} NMR spectroscopy. Due to the complexity of the spin system AA'BB'X (A, A', B, B' = ¹H; X = 31P) of 2, a simulation of the ¹H NMR spectra was done and it's in agreement with the bibliography.

Solid-phase microextraction for determination of 3-chloro-4-(dichloromethyl)-5-hydroxy-2[5H]-furanone in water

Solid-phase microextraction, using on-line bis(trimethylsilyl)trifluoroacetamide derivatisation, gas chromatography, and mass spectrometry, was evaluated in the quantification of 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX) in water samples. Fibres encompassing a wide range of polarities were used with headspace and direct immersion sampling. For the immersion procedure, various parameters affecting MX extraction, including pH, salinity, temperature, and extraction time were evaluated. The optimised method (polyacrylate fibre; 20% Na2SO4; pH 2.0; 60 min; 20 °C) was applied for reservoir chlorinated water samples-either natural or spiked with MX (50 ng L-1 and 100 ng L-1). The recovery of MX ranged from 44 to 72%. Quantification of MX in water samples was done using external standard and the selected ion monitoring mode. Correlation coefficient (0.98%), relative standard deviation (5%), limit of detection (30 ng L-1) and limit of quantification (50 ng L-1) were obtained from calibration curve.

Modification of oxidative status in Plasmodium berghei-infected erythrocytes by E-2-chloro-8-methyl-3-[(4'-methoxy-1'-indanoyl)-2'-methyliden]-quinoline compared to chloroquine

E-2-chloro-8-methyl-3-[(4'-methoxy-1'-indanoyl)-2'-methyliden]-quinoline (IQ) is a new quinoline derivative which has been reported as a haemoglobin degradation and ß-haematin formation inhibitor. The haemoglobin proteolysis induced by Plasmodium parasites represents a source of amino acids and haeme, leading to oxidative stress in infected cells. In this paper, we evaluated oxidative status in Plasmodium berghei-infected erythrocytes in the presence of IQ using chloroquine (CQ) as a control. After haemolysis, superoxide dismutase (SOD), catalase, glutathione cycle and NADPH + H+-dependent dehydrogenase enzyme activities were investigated. Lipid peroxidation was also assayed to evaluate lipid damage. The results showed that the overall activities of glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase were significantly diminished by IQ (by 53.5% and 100%, respectively). Glutathione peroxidase activity was also lowered (31%) in conjunction with a higher GSSG/GSH ratio. As a compensatory response, overall SOD activity increased and lipid peroxidation decreased, protecting the cells from the haemolysis caused by the infection. CQ shared most of the effects showed by IQ; however it was able to inhibit the activity of isocitrate dehydrogenase and glutathione-S-transferase. In conclusion, IQ could be a candidate for further studies in malaria research interfering with the oxidative status in Plasmodium berghei infection.

Modulation of trans-to-cis photoisomerization and photoluminescence of 1,2-bis(4-pyridyl)ethylene or 4-styrylpyridine coordinated to fac-tricarbonyl(5-chloro-1,10-phenathroline)rhenium(I)

Photochemical and photophysical properties of fac-[Re(CO)(3)(Clphen)(trans-L)](+) complexes, Clphen = 5-chloro-1,10-phenathroline and L = 1,2-bis(4-pyridyl)ethylene, bpe, or 4-styrylpyridine, stpy, were investigated to complement the understanding of intramolecular energy transfer process in tricarbonyl rhenium(I) complexes having an electron withdrawing group attached to polypyridyl ligands. These new compounds were synthesized, characterized and the photoisomerization quantum yields were accurately determined by (1)H NMR spectroscopy. The true quantum yields for fac-[Re(CO)(3)(Clphen) (trans-bpe)](+) were constant (Phi = 0.55) at all investigated irradiation wavelengths. However, for fac-[Re(CO)(3)(Clphen)(trans-stpy)](+), similar true quantum yields were observed only at higher energy irradiation (Phi(313 nm) = 0.53 and Phi(365 nm) = 0.57), but it decreased significantly at 404 nm (Phi = 0.41). These results indicated different deactivation pathways for the trans-stpy complex photoisomerization. Quantum yields decreased as the (3)IL(trans-L) and (3)MLCT(Re -> NN) excited states become closer and the behavior was discussed in terms of the excited state energy gaps. Additionally, luminescence properties of photoproducts, fac-[Re(CO)(3)(Clphen)(cis-L)](+), were also investigated in different environments to analyze the relative energy of the (3)MLCT(Re -> Clphen) excited state for each compound. (C) 2011 Elsevier B.V. All rights reserved.

Farmacocinética pré-clínica e avaliação toxicológica preliminar da nova tiazolidinadiona desenvolvida para o tratamento do diabetes mellitus tipo 2: 5-(4-cloro-benzilideno)-3-(4-metil-benzil)-tiazolidina-2,4-diona (GQ-2)

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Reversible addition–fragmentation chain transfer polymerization of 2-chloro-1,3-butadiene

Controlled polymerization of 2-chloro-1,3-butadiene using reversible addition–fragmentation chain transfer (RAFT) polymerization has been demonstrated for the first time. 2-Chloro-1,3-butadiene, more commonly known as chloroprene, has significant industrial relevance as a crosslinked rubber, with uses ranging from adhesives to integral automotive components. However, problems surrounding the inherent toxicity of the lifecycle of the thiourea-vulcanized rubber have led to the need for control over the synthesis of poly(2-chloro-1,3-butadiene). To this end, four chain transfer agents in two different solvents have been trialed and the kinetics are discussed. 2-Cyano-2-propylbenzodithioate (CPD) is shown to polymerize 2-chloro-1,3-butadiene in THF, using AIBN as an initiator, with complete control over the target molecular weight, producing polymers with low polydispersities (Mw/Mn < 1.25 in all cases).

(5R)-3-(2-Chloroacetyl)-4-methyl-5phenyl-1,3,4-oxadiazinan-2-one

The 1,3,4-oxadiazinan-2-one ring in the title compound, C(12)H(13)ClN(2)O(3), is in a distorted half-chair conformation. The phenyl and chloroacetyl groups occupy axial and equatorial positions, respectively, and lie to the opposite side of the molecule to the N-bound methyl substituent. Molecules are consolidated in the crystal structure by C-H center dot center dot center dot O interactions.

Synthesis, structure and magnetism of the oxalato-bridged chromium(III) complex [NBu4n](4)[Cr-2(ox)(5)]center dot 2CHCl(3)

The binuclear complex [NBu4n](4)[Cr-2(ox)(5)]. 2CHCl(3) has been prepared by an ion-exchange procedure employing Dowex 50WX2 cation-exchange resin in the n-butylammonium form and potassium tris(oxalato)chromate(III). The dimeric complex was characterised by a crystal structure determination: monoclinic, space group C2/c, a = 29.241(7), b = 15.192(2), c = 22.026(5) Angstrom, beta = 94.07(1)degrees, Z = 4. The magnetic susceptibility (300-4.2 K) indicated that the chromium(III) sites were antiferromagnetically coupled (J = -3.1 cm(-1)).

Synthesis of fluorinated 2-phenyl-4-quinolones from pyrrole-2,3-diones

A series of substituted 2-phenyl-4-quinolones 8-11 have been synthesized in good yields via ash vacuum thermolysis (FVT) of 1-aryl-4-cyano-5-phenylpyrrole-2,3-diones 7a-e and 1-aryl-4-methoxycarbonyl-5-phenylpyrrole-2,3-diones 7f-j. The pyrrolediones 7 were prepared from amines 3 and benzoylacetonitriles 5a-e or methyl 3-arylamino-3-phenylprop-2-enoates 5f-j.

1.° Chronica de narratione inchoationis et promotionis ordinis Cartusiensis. — 2.° Chronica de exordio ordinis Cartusiensis. — 3.° Bernardus de contemplatione. — 4.° Responsiones cujusdam Prioris majoris Cartusiae ad quemdam Monachum ejusdem ordinis Cartusiensis, Bonifacium nomine. — 5.° Miraculum de sancto Mauricio et Udone, Episcopo, editum anno 955. — 6.° Nonnulla ad vitam sancti Ludovici, Regis Francorum, spectantia. — 7.° Tractatus de approbatione et confirmatione ordinis Cartusiensis à sancta Romana Ecclesia : ad calcem subjicitur epistola concilii Basileensis ad Cartusienses. — 8.° Practica, quomodo procedi solet in electione Priorum ordinis Cartusiensis.

Colbertinus

1.° Bartholomaei Facii ad Alphonsum Regem dialogus de vitae felicitate. — 2.° Ejusdem epistola ad Robertum Strozam. — 3.° Mafei Vegii, Laudensis, dialogus de felicitate et miseria. — 4.° Ejusdem ad Eustachium, fratrem suum, dialogus de injuriis veritati illatis. — 5.° Anonymi dialogus inter Epicureum et Stoïcum de virtute et voluptate. — 6.° Platonis dialogus de morte contemnenda : interprete Cincio, Romano. — 7.° Plutarchi sermo de virtute et vitio : eodem interprete. — 8.° Apologia Socratis : authore Platone ; interprete verò Leonardo Aretino. — 9.° Platonis Crito : interprete anonymo. — 10.° Luciani Toxaris, sive, dialogus de amicitia : interprete anonymo.

Rogerii de Gaignieres