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Abstract: One-to-one mixtures of Co(hfpip and hfnip)2; hfpip=1,1,1,5,5,5-hexafluoro-4-(phenylimino)-2-pentanonato and hfnip=1,1,1,5,5,5-hexafluoro-4-(1-naphthylimino)-2-pentanonato, and 1,3-phenylenebis(4-pyridyldiazomethane), D2py2 , gave diazo-cobalt complexes, 1 and 2, respectively, formulated by [Co(hfpip and hfnip)2(D2py2)] n . Complex 2 was obtained as a single crystal and was found to have a zig-zag chain structure in the cis coordination of pyridines in D2py2 to the cobalt ions by X-ray crystallography. After irradiation of microcrystalline samples of 1 and 2, the generated carbene-cobalt complexes, 1c and 2c, showed magnetic properties due to ferromagnetic chains. Those complexes exhibited slow magnetic relaxations with U eff/k B =109 and 129K and temperature-dependent hysteresis loops with H c =11 and 9kOe at 1.9K for 1c and 2c, respectively. [Copyright &y& Elsevier]

Abstract: The mixtures of Co(X-hfpip)2; X=I and H, and bisdiazo-dipyridine ligands, D2py2 (TBA), in 1:1 ratios gave the discrete cobalt complexes, 1 and 2, respectively. The molecular structures for 1 and 2 revealed by X-ray crystallography were cyclic 2:2 cobalt complexes formulated as [(Co(X-hfpip) 2 ) 2 (D2py2 (TBA)) 2 ], in which the cobalt units were compressed octahedra. After irradiation of the microcrystalline samples, the resulting Co–carbene complexes, 1c and 2c, showed SMM behaviors exhibiting slow magnetic relaxations. In dc and ac magnetic susceptibility experiments, the activation barrier, U eff, for reorientation of the magnetic moment were estimated to be 139 and 135K for 1c and 2c, respectively, and the hysteresis loops of the magnetization (the coercive force, H c, and 26 and 15kOe at 1.9K for 1c and 2c, respectively) were observed. In addition, the values of the quantum tunneling time, τ Q, were determined to be 1.1×105 and 5.4×105 s (t 1/2 =21 and 104h) for 1c and 2c, respectively, below 2.5K. [Copyright &y& Elsevier]

Renal cyclooxygenase (COX) derived eicosanoids are elevated and lipoxygenase (LOX) products are reduced in the Han:SPRD- Cy rat model of polycystic kidney disease (PKD). Selective COX2 inhibition reduces kidney disease progression, but COX1 levels also are elevated in this model. Since the effect of reducing the products of both COX isoforms and the role of LOX products is not known, weanling normal and diseased Han:SPRD- cy littermates were given either low dose acetylsalicylic acid (ASA), nordihydroguaiaretic (NDGA) or no treatment for eight weeks. Renal eicosanoids were altered in the diseased compared to normal cortex, with COX products being higher and LOX products being lower. ASA reduced COX products, cyst growth and kidney water content, while NDGA reduced LOX products without altering disease progression or kidney function. Hence, a human equivalent ASA dose equal to less than one regular strength aspirin per day slowed disease progression, while further reduction of LOX products did not worsen disease progression. [ABSTRACT FROM AUTHOR]