41 resultados para N-N-S donor ligands

em Deakin Research Online - Australia


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The synthesis of [R2Sn(H2O)2(OPPh3)2](O3SCF3)2 (R = Me (1), Bu (2)) by the consecutive reaction of R2SnO (R = Me, Bu) with triflic acid and Ph3PO is described. Compounds 1 and 2 feature dialkyltin(IV) dications [R2Sn(H2O)2(OPPh3)2]2+ apparently stabilized by the neutral ligands in the solid state. Compounds 1 and 2 readily dehydrate upon heating at 105 and 86 °C, respectively. The preparative dehydration of 1 afforded [Me2Sn(OPPh3)2(O3SCF3)](O3SCF3) (1a), which features both bidentate and non-coordinating triflate anions. In compounds 1 and 2 the ligands Ph3PO and H2O are kinetically labile in solution and undergo reversible ligand exchange reactions. Compounds 1, 1a and 2 were characterized by multinuclear solution and solid-state NMR spectroscopy, IR spectroscopy, electrospray mass spectrometry, conductivity measurements, thermogravimetry and X-ray crystallography.


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In the matter of Re Patrick, Guest J of the Family Court of Australia held that a sperm donor, known to the lesbian mother of the child, had a right under Australian law to regular contact with the child to the extent that this was in the child's best interests. However, his Honour also held that due to the way in which particular provisions of the Family Law Act 1975 (Cth) are drafted, a sperm donor cannot be regarded as the "parent" of the child, and accordingly called for legislative reform to recognise the rights of known sperm donors wanting involvement with the child. In this article, the authors will first explore the facts and decision in Re Patrick, and then outline a proposal to amend the Family Law Act 1975 so that sperm donors can apply for an order to be a 'parent' under the Act.

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The synthesis and characterization of unsymmetric diorganotellurium compounds containing a sterically demanding I-naphthyl or
mesitylligand and a small bite chelating organic ligand capable of 1,4-Te···N(O) intramolecular interaction is described. The reaction
of ArTeCl3 (Ar = I-ClOH7, Np; 2,4,6-Me3C6H2' Mes) with (SB)HgCI [SB = the Schiff base, 2-(4,4'-N02C6H4CH=NC6H3-Me)] or a methyl ketone (RCOCH3) afforded the corresponding dichlorides (SB)ArTeCI2 (Ar = Np, 1Aa; Mes, 1Ba) or (RCOCH2)ArTeCl2 (Ar = Np; R = Ph (2Aa), Me (3Aa), Np (4Aa); Ar = Mes, R = Ph (2Ba)). Reduction of 1Aa and 1Ba by Na2S205 readily gave the tellurides (SB)ArTe (Ar = Np (1A), Mes, (1B) but that of dichlorides derived from methylketones was complicated due to partial decomposition to tellurium powder and diarylditelluride (Ar2Te2), resulting in poor yields of the corresponding tellurides 2A, 2B and 3A. Oxidation of the isolated tellurides with S02Cl2, Br2 and I2 yielded the corresponding dihalides. All the synthesized compounds have been characterized with the help of IR, 1H, l3C, and 125Te NMR and in the case of 2Aa, and 2Ba by X-ray crystallography. Appearance of only one 125Te signal indicated that the unsymmetric derivatives were stable to disproportionation to symmetric species. Intramolecular 1,4-Te· . ·0 secondary bonding interactions (SBIs) are exhibited in the crystal structures of both the tellurium(IV) dichlorides, 2Aa, and 2Ba. Steric repulsion of the mesityl group in the latter dominates over lone pair-bond pair repulsion, resulting in significant widening of the equatorial C-Te-C angle. This appears to be responsible for the lack of Te· . ·CI involved supramolecular associations in the crystal structure of 2Ba.

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This paper examines the potential for using service blueprinting to assist non-profit organizations in better managing donor exchanges. In many cases organizations are unclear of donors' expectations in relation to the overall giving experience. Failure to deliver on expectations could potentially result in donor 'dissatisfaction', which in turn may result in reductions of future donations to these organizations. This article begins with a review of blueprinting and the benefits of using such as tool as to assist in understanding the donation exchange. Zeithaml and Bitner's (2000) steps in building a blueprint are explained in the context of non-profit-donor exchanges. An example of a hypothetical blueprint provided to highlight the complexity and divergence encountered in such exchanges and used to identify potential problems associated with the various aspects of the donation experience. Finally, implications for managing giving and suggestions for future research are offered.

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A class of new conjugated copolymers containing a donor (thiophene)−acceptor (2-pyran-4-ylidene-malononitrile) was synthesized via Stille coupling polymerization. The resulting copolymers were characterized by 1H NMR, elemental analysis, GPC, TGA, and DSC. UV−vis spectra indicated that the increase in the content of the thiophene units increased the interaction between the polymer main chains to cause a red-shift in the optical absorbance. Cyclic voltammetry was used to estimate the energy levels of the lowest unoccupied molecular orbital (LUMO) and the highest occupied molecular orbital (HOMO) and the band gap (Eg) of the copolymers. The basic electronic structures of the copolymers were also studied by DFT calculations with the GGA/B3LYP function. Both the experimental and the calculated results indicated an increase in the HOMO energy level with increasing the content of thiophene units, whereas the corresponding change in the LUMO energy level was much smaller. Polymer photovoltaic cells of a bulk heterojunction were fabricated with the structure of ITO/PEDOT/PSS (30 nm)/copolymer−PCBM blend (70 nm)/Ca (8 nm)/Al (140 nm). It was found that the open-circuit voltage (Voc) increased (up to 0.93 V) with a decrease in the content of thiophene units. Although the observed power convention efficiency is still relatively low (up to 0.9%), the corresponding low fill factor (0.29) indicates considerable room for further improvement in the device performance. These results provided a novel concept for developing high Voc photovoltaic cells based on donor-π-acceptor conjugated copolymers by adjusting the donor/acceptor ratio.

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Nitric oxide (NO) has been implicated as an important signaling molecule in the insulin-independent, contraction-mediated glucose uptake pathway and may represent a novel strategy for blood glucose control in patients with type 2 diabetes (T2DM). The current study sought to determine whether the NO donor, sodium nitroprusside (SNP) increases glucose uptake in primary human skeletal muscle cells (HSkMC) derived from both healthy individuals and patients with T2DM. Vastus lateralis muscle cell cultures were derived from seven males with T2DM (aged 54 ± 2 years, BMI 31.7 ± 1.2 kg/m2, fasting plasma glucose 9.52 ± 0.80 mmol/L) and eight healthy individuals (aged 46 ± 2 years, BMI 27.1 ± 1.5 kg/m2, fasting plasma glucose 4.69 ± 0.12 mmol/L). Cultures were treated with both therapeutic (0.2 and 2 μM) and supratherapeutic (3, 10 and 30 mM) concentrations of SNP. An additional NO donor S-nitroso-N-acetyl-D,L-penicillamine (SNAP) was also examined at a concentration of 50 μM. Glucose uptake was significantly increased following both 30 and 60 min incubations with the supratherapeutic SNP treatments (P = 0.03) but not the therapeutic SNP doses (P = 0.60) or SNAP (P = 0.54). There was no difference in the response between the healthy and T2DM cell lines with any treatment or dose. The current study demonstrates that glucose uptake is elevated by supratherapeutic, but not therapeutic doses of SNP in human primary skeletal muscle cells derived from both healthy volunteers and patients with T2D. These data confirm that nitric oxide donors have potential therapeutic utility to increase glucose uptake in humans, but that SNP only achieves this in supratherapeutic doses. Further study to delineate mechanisms and the therapeutic window is warranted.

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In 1991, the World Health Assembly approved a set of Guiding Principles which emphasize voluntary donation, non-commercialization and a preference for cadavers over living donors” (World Health Organization). The objective of this paper is to identify the factors that affect the ratio of cadaveric transplants to all transplants. This paper first provides informational background on problems surrounding kidney transplants and then uses a theoretical framework which employs standard economic assumptions but incorporates a setup where the persons needing kidneys can obtain it from their compatible relatives or purchase it from individuals who are willing to sell one of their kidneys. The methods of economic theoretical analyses are used where following definitions and assumptions some conclusions are drawn. This paper finds that factors such as inequality, rule of law and religion have significant effect on the ratio of cadaveric transplants to all transplants. The paper concludes that improvement in equality and in rule of law will increase the use of cadaveric kidney transplants. In addition, fighting religious beliefs against cadaveric kidney transplants too will lead to a higher ratio of cadaveric transplants to all transplants.

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The study, carried out within an infertility support group, concern disclosure of donor conception and its possible effects upon our constructions of conception, kinship and identity. It also examines perceptions of rights, information and its access or denial, knowledge/power, secrecy and the medicalization of reproduction.

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Derivatives of pharmaceutical compounds that could potentially bind irreversibly to a hypertension controlling receptor were synthesised to provide tools for studying this receptor. Also compounds that simultaneously activate two cardiovascular receptors with opposing cellular mechanisms were synthesised. This resulted in a desired partial reduction in the activity of one receptor.

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The mechanisms responsible for the immunosuppression associated with sepsis or some chronic blood infections remain poorly understood. Here we show that infection with a malaria parasite (Plasmodium berghei) or simple systemic exposure to bacterial or viral Toll-like receptor ligands inhibited cross-priming. Reduced cross-priming was a consequence of downregulation of cross-presentation by activated dendritic cells due to systemic activation that did not otherwise globally inhibit T cell proliferation. Although activated dendritic cells retained their capacity to present viral antigens via the endogenous major histocompatibility complex class I processing pathway, antiviral responses were greatly impaired in mice exposed to Toll-like receptor ligands. This is consistent with a key function for cross-presentation in antiviral immunity and helps explain the immunosuppressive effects of systemic infection. Moreover, inhibition of cross-presentation was overcome by injection of dendritic cells bearing antigen, which provides a new strategy for generating immunity during immunosuppressive blood infections.

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This paper reports an empirical study of the factors affecting burden sharing among OECD's 22 DAC members in 'bankrolling' the multilateral aid agencies. Annual data over 1970–2000, pooled across the donor countries, form the basis for the empirical estimation of each donor's share in the ODA aid receipts for each multilateral agency. Our findings suggest the existence of reverse exploitation, i.e., the financial burden of the agencies is disproportionally carried by the smaller donors. The study also finds that factors such as inherent donor generosity, donor concern for domestic egalitarianism, and the extent to which donors are pro-poor in their bilateral aid policies have an impact on their readiness to support multilateral agencies financially. Size of the donor government and its budgetary balance positively influence burden sharing of contributions to other multilateral agencies. But neither the phase of economic cycle nor the rate of economic growth affects the burden-sharing responsibility of donors. It was also observed that contributions by EU members to the EC do not appear to crowd-out their contributions to other multilateral aid agencies and that right-wing donor governments are generally more parsimonious with regard to financial assistance to multilateral aid agencies. The preferred alternative, particularly among EU member countries, appears to be the EC.

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The preparations and characterisations of a range of lanthanoid 4-(R)-substituted (4-Rcinn, R = OH, OMe, NO2, Cl), known to have good anticorrosion properties, are reported. The crystal structure of [Ce(4-OHcinn)3(MeOH)2(H2O)]·MeOH is a polymer, in which the cerium atoms are nonacoordinate, and adjacent cerium atoms are bridged by either two bridging bidentate or two bridging tridentate carboxylate ligands. Each cerium atom also has one monodentate 4-hydroxycinnamate ligand, one aqua ligand, and two methanol ligands.