Trichloro-mono-beta-diketonato oxorhenium(V) complexes: synthesis, characterization and crystal structure

Oxorhenium(V) complexes of beta-diketonate systems have been synthesized and isolated in pure form. The red complexes n-Bu4N[ReO(R1COCHCOR2)Cl-3] (acac, R-1=R-2=CH3; bzac, R-1=CH3 and R-2=C6H5; bzbz, R-1=R-2=C6H5) have been characterized by elemental analyses, spectroscopic and other physico-chemical tools. One complex, n-Bu4N[ReO(bzbz)Cl-3] (1c) has been subjected to single-crystal X-ray analysis. In the structure of the anion, the metal has a six-coordinate octahedral environment in which the bidentate -diketone ligand is cis and trans to the terminal oxygen.

Oxorhenium(V) complexes with tetradentate NSNO pyridylthioazophenolates: syntheses, spectral and electrochemical studies

A family of oxorhenium (V) complexes of newly designed pyridylthioazophenolate ligands has been synthesized and isolated in pure form. The solid state structure of an organic compound (HL1) has been established by X-ray crystallography. The molecular structure observed in the solid state is that the two molecules of the ligand (HL1) in the asymmetric unit have similar geometries, except for the orientation of the pyridine ring. This series of organic moieties acts as tetradentate monobasic NSNO donor chelators in oxorhenium(V) complexes which has been characterized by elemental analyses, IR, H-1-NMR, UV-Vis. The complexes are 1: 1 electrolytes in nature in MeOH solution, the counter anion being ClO4). The electrochemical studies of the [(ReO)-O-V(L)Cl]ClO4 complexes in MeCN using TBAP as supporting electrolyte exhibit quasi-reversible voltammogram showing one-electron couple for [(ReO)-O-VI(L)Cl](2+)-[(ReO)-O-V(L)Cl](+) in the 1.11-1.29 V vs SCE range.

Oxorhenium(V) Complexes with 2,3-Dihydroxynaphthalene

2,3-Dihydroxynaphthalene (H(2)dhn) reacts with [ReOCl(3)-(PPh(3))(2)] or [ReOBr(3)(PPh(3))(2)] in a 1:1 molar ratio with formation of the isostructural complexes [ReOCl(2)(PPh(3))(2)(Hdhn)] (4) and [ReOBr(2)-(PPh(3))(2)(Hdhn)] (5). They have distorted octahedral coordination spheres with the halide and the triphenylphosphine ligands arranged in equatorial trans positions to each other. The Hdhn-ligand coordinates monodentately in trans position to the oxo ligand. Intramolecular hydrogen bonds between the Hdhn and the halogeno ligands stabilize this coordination mode. The products represent the first examples of oxorhenium(V) complexes with monodentate catecholate-type ligands.

Synthesis, Structural Characterization, and Biological Evaluation of Oxorhenium(V) Complexes with a Novel Type of Thiosemicarbazones Derived from N-[N `,N `-Dialkylamino(thiocarbonyl)]benzimidoyl Chlorides

Reactions of N-[N`,N`-diethylamino(thiocarbonyl)]benzimidoyl chloride with 4,4-dialkylthiosemicarbazides give a novel class of thiosemicarbazides/thiosemicarbazones, H(2)L, which causes a remarkable reduction of cell growth in in vitro experiments. These strong antiproliferative effects are also observed for oxorhenium(V) complexes of the general composition [ReOCl(L)], which are formed by reactions of the potentially tridentate ligands with (NBu(4))[ReOCl(4)]. A systematic substitution of the alkyl groups in the thiosemicarbazone building blocks of the ligands do not significantly influence the biological activity of the metal complexes, while the replacement of the chloro ligand by a PPh(3) ligand (by the replacement of the oxo unit by a nitrido ligand) completely terminated the cytotoxicity of the metal complexes.

Oxo-rhenium(V) complexes with bidentate phosphine ligands: synthesis, crystal structure and catalytic potentiality in epoxidation of olefins using hydrogen peroxide activated bicarbonate as oxidant

Two oxorhenium(V) complexes with bidentate phosphine ligands were synthesized and isolated as [ReOCl3(dppm)] 1 and [ReOCl3(dppp)] 2 [where dppm = 1,1-bis(diphenylphosphino) methane and dppp = 1.3-bis(diphenylphosphino) propanel. Complex 2 was structurally characterized. Both the complexes were used as catalysts in the epoxidation of olefins using NaHCO3 as co-catalyst and H2O2 as terminal oxidant. (c) 2008 Elsevier B.V. All rights reserved.

Rhenium chelate complexes with maltolate or kojate

Novel rhenium complexes containing the maltolate (mal) or kojate (koj) anions as chelating ligands have been synthesized: [ReOCl(mal)(2)] (1), [ReOCl(2)(mal)(PPh(3))] (2), [ReOBr(2)(mal)(PPh(3))] (3), [ReOCl2(koj)(PPh(3))] (4) and [ReOBr(2)(koj)(PPh(3))] (5). The products have been characterized by MR, (1)H, (13)C, and (31)P NMR spectroscopies and elemental analysis. The crystal and molecular structures of all complexes were determined. Complex I crystallizes monoclinic, space group C2/c, Z = 8. It contains two O, O`-bidentate maltolate ligands and one chloro ligand at the (ReO)(3+) unit, so that a distorted octahedral geometry is adopted by the six-coordinated rhenium(V) center. The chloro ligand occupies a cis position to the oxo ligand. Complexes 2 and 3 are isostructural and crystallize orthorhombic, space group Pbca and Z = 8. The isostructural complexes 4 and 5 crystallize monoclinic, space group P2(1)/n and Z = 4. In complexes 2-5, the (ReO)(3+) unit is coordinated by a monoanionic O,O-bidentate unit of the maltolate (2 and 3) or kojate (41 and 5) ligand, one triphenylphosphine and two halogeno ligands (Cl in 2 and 4; Br in 3 and 5), with the rhenium(V) center in a distorted octahedral environment. The halide ligands are in cis positions to each other. (c) 2008 Elsevier Ltd. All rights reserved.

Mixed-Ligand Complexes of Technetium and Rhenium with Tridentate Benzamidines and Bidentate Benzoylthioureas

Mixed-ligand complexes of technetium(V) or rhenium(V) containing tridentate N-[(dialkylamino)(thiocarbonyl)]benzamidine (H(2)L(1)) and bidentate N,N-dialkyl-N`-benzoylthiourea (HL(2)) ligands were formed in high yields when (NBu(4))[MOCl(4)] (M = Tc or Re) or [ReOCl(3)(PPh(3))(2)] was treated with mixtures of the proligands. Other approaches for the synthesis of the products are reactions of [MOCl(L(1))] complexes with HL(2) or compounds of the-composition [ReOCl(2)(PPh(3))(L(2))] with H(2)L(1). The resulting air-stable [MO(L(1))(L(2))] complexes possess potential for the development of metal-based radiopharmaceuticals. [TcO(L(1))(L(2))] complexes are readily reduced by PPh3 with formation of [Tc(L(1))(L(2))(PPh(3))]. The resulting Tc(III) complexes undergo two almost-reversible oxidation steps corresponding to one-electron transfer processes. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

Statutory protections from forfeiture of a leasehold estate following Apriaden Pty Ltd v Seacrest Pty Ltd

In Apriaden Pty Ltd v Seacrest Pty Ltd the Victorian Court of Appeal decided that termination of a lease under common law contractual principles following repudiation is an alternative to reliance upon an express forfeiture provision in the lease and that it is outside the sphere of statutory protections given against the enforcing of a forfeiture. The balance of authority supports the first aspect of the decision. This article focuses on the second aspect of it, which is a significant development in the law of leases. The article considers the implications of this decision for essential terms of clauses in leases, argues that common law termination for breach of essential terms should be subject to compliance with these statutory requirements and, as an alternative, suggests a way forward through appropriate law reform, considering whether the recent Victorian reform goes far enough.

Enhancement of DNA repair using topical T4 endonuclease V does not inhibit melanoma formation in Cdk4R24C/R24C/Tyr-NrasQ61K mice following neonatal UVR

To further investigate the use of DNA repair-enhancing agents for skin cancer prevention, we treated Cdk4R24C/R24C/NrasQ61K mice topically with the T4 endonuclease V DNA repair enzyme (known as Dimericine) immediately prior to neonatal ultraviolet radiation (UVR) exposure, which has a powerful effect in exacerbating melanoma development in the mouse model. Dimericine has been shown to reduce the incidence of basal-cell and squamous cell carcinoma. Unexpectedly, we saw no difference in penetrance or age of onset of melanoma after neonatal UVR between Dimericine-treated and control animals, although the drug reduced DNA damage and cellular proliferation in the skin. Interestingly, epidermal melanocytes removed cyclobutane pyrimidine dimers (CPDs) more efficiently than surrounding keratinocytes. Our study indicates that neonatal UVR-initiated melanomas may be driven by mechanisms other than solely that of a large CPD load and/or their inefficient repair. This is further suggestive of different mechanisms by which UVR may enhance the transformation of keratinocytes and melanocytes.

Artful determination : "state of the art" and PCME Ltd v. Goyen COntrols Co. UK Ltd

In a recent decision by Mr Justice Laddie, a patent was held anticipated by, inter alia, prior use of a device which fell within the claims of the patent in suit, even though its circuitry was enclosed in resin. The anticipating invention had been "made available to the public" within the terms of section 2 (2) of the Patents Act 1977 because its essential integers would have been revealed by an interesting character, the "skilled forensic engineer".

Locking away the mysteries of fair basis : Lockwood v Doric in the High Court

This article updates a previous article on the Lockwood v Doric fair basing case in the Full Court of the Federal Court which was recently appealed to the High Court. The High Court's decision provides a new and welcome level of clarity in this difficult area of patent law. With this new clarity we can finally lock away some of the mysteries that have plagued the area for some time. Already, indications are that Lockwood's guidelines are being usefully applied in the Patent Office and Federal Court.

Recent developments : loss of chance in medical litigation : Tabet v Gett [2010] HCA 12.

Following the judgement of the High Court in Tabet v Gett [2010]HCA 12 handed down on 21 April 2010 it appears that in Australia there is now very limited scope for recovery in negligence for the loss of a chance of a better medical outcome.

Oxford Companion to Australian Gardens [contributions: entries S-V]

Shelton, Edward Mason; p.548 Sherwood Arboretum; p.550 Soutter, William; pp.563-564 Styles or gardens and designed landscapes; pp.575-576 Summer-house; pp.579-580 Trapnell, Walter George; p.602 Tropical Gardens; pp.604-605 Wickham Park; p.642 Wijaya, Made; p.642 Williams, George; p.644 Williams, Keith A.W.; p.644 Verandah Garadening; p.614

A myosin from a higher plant has structural similarities to class V myosins

In plant cells, myosin is believed to be the molecular motor responsible for actin-based motility processes such as cytoplasmic streaming and directed vesicle transport. In an effort to characterize plant myosin, a cDNA encoding a myosin heavy chain was isolated from Arabidopsis thaliana. The predicted product of the MYA1 gene is 173 kDa and is structurally similar to the class V myosins. It is composed of the highly-conserved NH2-terminal "head" domain, a putative calmodulin-binding "neck" domain an alpha-helical coiled-coil domain, and a COOH-terminal domain. Northern blot analysis shows that the Arabidopsis MYA1 gene is expressed in all the major plant tissues (flower, leaf, root, and stem). We suggest that the MYA1 myosin may be involved in a general intracellular transport process in plant cells.

Contribution of transmembrane domain V amino acids to β1l-adrenoceptor activity and affinity

Introduction. There are two binding sites on the β1-adrenoceptor (AR), β1H and β1L corresponding to high and low affinity binding sites respectively, which can be activated to cause cardiostimulation. Some β-blockers that block β1AR and β2ARs can activate β1LARs at higher concentrations than those required to cause blockade. The β2AR does not form a corresponding low affinity binding site and therefore we postulated that heterologous amino acids are responsible for the formation of β1LAR. Aim. To investigate whether heterologous amino acids of transmembrane domain V (TMDV) of β1AR and β2ARs contribute to β1LAR. Methods. β1ARs, β2ARs and mutant β1ARs containing all (β1(β2TMDV)AR) or single amino acids of TMDV of the β2AR were prepared and stably expressed in Chinese Hamster Ovary cells. Concentration-effect curves for cyclicAMP accumulation were carried out for (-)-CGP12177 in the absence or presence of (-)-bupranolol. Results. The potencies (pEC50) of (-)-CGP12177 were β2AR (9.24 ± 0.14, n = 5), β1(V230I)AR (9.07 ± 0.07, n = 10), β1(β2TMDV)AR (8.86 ± 0.10, n = 15), β1(R222Q)AR (8.09 ± 0.29, n = 6), β1AR (8.00 ± 0.11, n = 11). The affinities (pKB) of (-)-bupranolol were β2AR (9.82 ± 0.52, n = 5), β1(V230I)AR (7.64 ± 0.12, n = 8), β1(β2TMV)AR (8.06 ± 0.17, n = 8), β1(R222Q)AR (7.33 ± 0.23, n = 5), β1AR (7.23 ± 0.23, n = 5). Discussion. The potency of (-)-CGP12177 was higher at β2AR than at β1AR consistent with activation through a low affinity site at the β1AR (β1LAR). The presence of V230 in β1AR accounted for the lower potency of (-)-CGP 12177. The affinity of (-)-bupranolol was lower at β1AR compared to β2AR. The presence of V230 in β1AR accounted in part for the lower affinity. In conclusion TMDV of the β1AR contributes in part to the low affinity binding site of β1AR.