bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dioxygen Oxidation of Coordinated Nitrosyl to Nitro on Dmf-Bridged Dinuclear CoPb Complex
Authors: Furutachi Hideki , Okawa Hisashi 
Published: August 2005

Abstract
The CoIIPbII complex [CoPb(L)(CH3OH)(ClO4)2] reacts with nitrogen monoxide to give the nitrosyl complex [CoPb(L)(NO)(dmf)2(ClO4)]ClO4 (1), where H2L is a dinucleating macrocycle derived from the [2 : 1 : 1] condensation of 2,6-diformyl-4-methylphenol, ethylenediamine, and diethylenetriamine and has a “salen”- and a “saldien”-like metal-binding site sharing the phenolic entities. 1 crystallizes in the triclinic space group , a = 12.729(4), b = 17.103(6), c = 10.548(4) Å, α = 107.42(4)°, β = 106.18(2)°, γ = 101.33(3)°, V = 2003(1) Å3, and Z = 2. The refinement converges with R = 0.045 and Rw = 0.049 for 3768 reflections with I &gt; 3.00σ(I). The Co resides in the “salen” site and the Pb in the “saldien” site. The metal ions are bridged by the two phenolic oxygens of L2− and a dmf oxygen, in the Co–Pb intermetallic separation of 3.511(2) Å. The Co–O(dmf) and O(dmf)–Pb bond distances are 2.14(1) and 3.072(8) Å, respectively. The NO coordinates to the Co at the axial site trans to the bridging dmf oxygen, providing a six-coordinate geometry about the metal; the Co–N(nitrosyl) distance is 1.92(1) Å and the Co–N–O angle is 117(1)°. The Pb has an eight-coordinate geometry together with the bridging dmf oxygen, a terminal dmf oxygen and a perchlorate oxygen. The nitrosyl complex 1 is oxidized with molecular oxygen to the nitro complex [CoPb(L)(NO2)(dmf)2(ClO4)]ClO4 (2). 2 crystallizes in the triclinic space group , a = 12.748(4), b = 17.139(5), c = 10.359(3) Å, α = 106.34(3)°, β = 106.44(3)°, γ = 101.42(3)°, V = 1986(1) Å3, and Z = 2. The refinement converges with R = 0.039 and Rw = 0.042 based on 6202 reflections with I &gt; 3.00σ(I). 2 has a dinuclear core very similar to that of 1, bearing an NO2 group instead of an NO group. The Co–N(nitro) bond distance is 1.889(6) Å. 1H NMR, 13C NMR, and 13C–1H COSY spectroscopies indicate that the dmf-bridged dinuclear cores of 1 and 2 are retained in solution.
Interglycosidic Acetals IV. Preparation and Regioselective Cleavage of Phenyl 2,2′ : 4,6 : 4′,6′-Tri-O-benzylidene-1-thio-β-laminaribiosides
Authors: Sakairi Nobuo , Okazaki Yasunori , Furukawa Jun-ichi , Kuzuhara Hiroyoshi , Nishi Norio , Tokura Seiichi 
Published: August 2005

Abstract
A (+)-10-Camphorsulfonic acid-catalysed acetal exchange reaction of phenyl 1-thio-β-laminaribioside using 3.5 molar equivalents of α,α-dimethoxytoluene gave a tris(benzylidene acetal), which was isolated and characterized as phenyl 3′-O-acetyl-2,2′ : 4,6 : 4′,6′-tri-O-benzylidene-1-thio-β-laminaribioside, and the corresponding 3′-O-benzyl derivative 6. Upon a treatment with pyridinium p-toluenesulfonate, the interglycosidic 2,2′-acetal in 6 underwent selective cleavage to give the 2,2′-diol. Additionally, a reductive ring-opening reaction of 6 with lithium aluminium hydride/anhydrous aluminium chloride, followed by O-acetylation, gave the 2,6,6′-O-acetyl-4,2′,3′,4′-tetra-O-benzyl derivative in 73% yield. A different regioselectivity was observed in the reduction of 6 with borane-trimethylamine adduct/anhydrous aluminium chloride or sodium cyanotrihydroborate/methanesulfonic acid, giving the corresponding 2,4,4′-triol as the major product.
Solvolysis of 1-[trans-2-(m- or p-Substituted Phenyl)cyclopropyl]-1-methylethyl p-Nitrobenzoates
Authors: Kusuyama Yoshiaki 
Published: August 2005

Abstract
The solvolyses of 1-[trans-2-(m- or p-substituted phenyl)cyclopropyl]-1-methylethyl p-nitrobenzoates in 80% aqueous acetone have been studied with regard to both reactivity and product composition. For the less reactive substituents such as m-Br, m-Cl, and m-CF3, the solvolysis products were the corresponding 2-(2-arylcyclopropyl)-2-propanol, indicating the cyclopropylmethyl cation intermediate. The ring-opened products increased as the electron-donating ability of the substituents increased. The application of the Yukawa–Tsuno equation to the reactivity afforded a ρ value of −1.43 and r value of 0.59 with a correlation coefficient of 0.997. A large value of r indicates the presence of the allylic cation intermediate where much more charge develops at the benzylic carbon for the derivatives with electron-donating substituents than is the case for the cyclopropylmethyl cation intermediate. Thus the solvolysis reaction proceeds via two independent pathways: one has a cyclopropyl cation intermediate and the other has a homoallylic cation intermediate.
The Stability of Seven-Coordinate Species of Earlier Members in the First Transition Series: Heptahydrated Ti(II), V(II), Cr(II), and Mn(II) Ions Relevant to Intermediate and Transition State in Water-Exchange Reaction
Authors: Tsutsui Yuko , Wasada Hiroaki , Funahashi Shigenobu 
Published: August 2005

Abstract
The structure and stability of heptahydrated divalent cations of earlier members in the first transition series ([M(H2O)7]2+: M = Ti, V, Cr, and Mn) have been studied by ab initio molecular-orbital methods, because the heptahydrated cations are relevant to intermediates and transition states in their water-exchange reactions. The structure is pentagonal bipyramidal with a distorted equatorial plane. The heptahydrated divalent cations with d0, d1, d2, and d5 configurations are at the local minima, and those with d3 and d4 are at the saddle points, though there is an increase in hydration energy across the row of the periodic table from calcium to zinc. The trend of stability in a series of heptahydrated divalent cations strongly depends on the d-electron configuration, and differs significantly in the case of the penta- or hexahydrated cations that are at the local minima. It is concluded that an associative mechanism is possible for the water-exchange reaction on hexahydrated divalent cations of the earlier members in an aqueous solution.
Lithiosilanes with Si–Si Bonds: Synthesis and 6Li, 7Li, and 29Si NMR Studies
Authors: Nanjo Masato , Sekiguchi Akira , Sakurai Hideki 
Published: August 2005

Abstract
Lithiopentamethyldisilane (LiSiMe2SiMe3, 1a), two isomer of lithioheptamethyltrisilane (LiSiMe2SiMe2SiMe3, 1b; LiSi(SiMe3)2Me, 1c), lithio[tris(trimethylsilyl)]silane (LiSi(SiMe3)3, 1d), 2-lithio-1,3-diphenylpentamethyltrisilane (LiSi(SiMe2Ph)2Me, 1e), 2-lithio-2-phenylhexamethyltrisilane (LiSi(SiMe3)2Ph, 1f), 3-lithio-1,5-diphenylnonamethylpentasilane (LiSi(SiMe2SiMe2Ph)2Me, 1g), lithio[bis(dimethlphenylgermyl)]methylsilane (LiSi(GeMe2Ph)2Me, 1h), and lithiotrimethylsilane (LiSiMe3, 3) were prepared by lithium–mercury exchange reactions. The unsolvated lithiosilanes exist as the aggregated oligomers in non-polar solvents, whereas those solvated by THF or Et2O exist as monomers. Synthesis and detailed spectroscopic studies of the lithiosilanes with Si–Si bonds are reported.
Dimensiosolvatic Effects. III. Quantification of Dimensiosolvatic Effects by Solvolyses of 2-Bromoadamantane in Water–Alcohol Mixtures
Authors: Oki Michinori , Ikeda Hiroshi , Toyota Shinji 
Published: August 2005

Abstract
Solvolyses of 2-bromoadamantane in aqueous alcohols were carried out to find the selectivities, kether/kalcohol, at various concentrations of water in an alcohol and at various temperatures. While the observed ratios contain a large error or fluctuate at low concentrations of water, they were almost constant for 1.0 : 0.8 alcohol/water mixtures. The selectivity was also independent of temperatures of the reaction. The significance of the selectivity, which is determined by the ease of solvent intervention into contact ion pairs, is discussed. D values, which are obtained by taking reciprocals of the selectivity for the 1.0 : 0.8 mixture, are proposed as a measure of the dimensiosolvatic effects when a solvent molecule intervenes into the contact ion pair.
Efficient Dimerization of Propene by Nickel-Phosphine Catalysis in the Presence of Sulfonic Acids and/or Dialkyl Sulfates. Effects of Phosphine Ligands and Additives
Authors: Itagaki Makoto , Suzukamo Gohfu , Nomura Kotohiro 
Published: August 2005

Abstract
The effect of the phosphines for the dimerization of propene using a nickel catalyst system consisting of nickel naphthenate, tertiary phosphine (PCy3, P(i-Pr)3, PEt3, PEt2Ph, and PPh3; Cy = cyclohexyl), triethylaluminum, and 2,4,6-trichlorophenol in the presence of sulfonic acids and/or dialkyl sulfates was investigated. A remarkable increase in both the catalytic activity (turnover number (TON) for the formation of C6 olefins) and the selectivity of dimers (selectivity of dimers based on the propene reacted) was observed, especially upon the addition of sulfonic acids, such as MeSO3H, CF3SO3H, and/or dialkyl sulfates (Me2SO4 or Et2SO4). The reaction products formed by the above catalyst system with PEt3 and PEt2Ph were exclusively C6 olefins (selectivity of dimers: 97 and 93%, respectively). It was also revealed in this catalyst system that the electronic factor of phosphine is important for the catalytic activity, and that the dimer’s proportion greatly depends upon the kind of phosphine used.
Fluorescence Detection of Hybrid Formation between Pyrrolidine-based Oxy-peptide Nucleic Acid and DNA
Authors: Kitamatsu Mizuki , Shigeyasu Masanori , Sisido Masahiko 
Published: August 2005

Abstract
When an oxy-peptide nucleic acid that contains pyrrolidine rings (pyrrolidine-based oxy-PNA = POPNA) hybridized with its complementary DNA, a fluorophore, DiSC2(5), bound specifically to the hybrid in aqueous solution. Free DiSC2(5) did not fluoresce by itself, but the bound DiSC2(5) showed strong fluorescence. The fluorescence was observed only on a fully-matched POPNA–DNA hybrid, but not on hybrids with even single mismatches. This finding provides bases for highly sensitive and highly specific detection of single nucleotide polymorphisms.
Chiral Bis-phosphoramidites Based on Linked-BINOL for Rhodium-catalyzed 1,4-Addition of Arylboronic Acids to α,β-Unsaturated Carbonyl Compounds
Authors: Yamamoto Yasunori , Kurihara Kazunori , Sugishita Noriyuki , Oshita Kengo , Piao Dongguo , Miyaura Norio 
Published: August 2005

Abstract
Cationic rhodium(I) complex prepared from Shibasaki’s linked-BINOL and [Rh(nbd)2]BF4 catalyzed asymmetric 1,4-addition of arylboronic acids to enones at room temperature with high enantioselectivities up to 99.8%ee.
Chemoselective Oxidation of Sulfides to Sulfoxides Using N-t-Butyl-N-chlorocyanamide
Authors: Kumar Vinod , Kaushik Mahabir Parshad 
Published: August 2005

Abstract
A simple, efficient and highly chemoselective method has been developed for the synthesis of sulfoxides from sulfides using N-t-butyl-N-chlorocyanamide as an oxidant in a mixed acetonitrile–water solution with a 1:1 mol ratio of oxidant to sulfides. N-t-butyl-N-chlorocyanamide, a source of positive chlorine, has been used for conversion of the variety of sulfides into their corresponding sulfoxides in quantitative yields.
Theoretical investigations of the reactivity of MO4 and the electronic structure of Na2[MO4(OH)2], where M=Ru, Os, and Hs (element 108)
Authors: Pershina V. 
Published: August 2005

Abstract
Fully relativistic, four-component, density functional theory calculations (4c-DFT) were performed for [MO4(OH)2]2- and Na2[MO4(OH)2], where M=Ru, Os, and Hs. The electronic structure of the Hs complex ion was shown to be similar to that of the Os complex ion, though [HsO4(OH)2]2- should be more covalent than the lighter congeners in group 8, by analogy with MO4. The calculations of the free energy change, Δ G
r, of the [MO4(OH)2]2- and Na2[MO4(OH)2] formation reactions from the volatile tetroxides and NaOH have shown that HsO4 should be slightly less reactive than OsO4, with the difference in ΔG
r being less than 52 kJ/mol. In the experimental study of the deposition of OsO4 and HsO4 on the surface of NaOH in the presence of water, such a difference in reactivity has not yet been clearly revealed. The anionic complex of Ru(VIII) was found to be much less stable than those of Os and Hs. Also, Delta;G
r for the formation of [RuO4(OH)2]2- from RuO4 was found to be ∼300 kJ/mol more positive than ΔG
r for analogous reactions of Os and Hs, which explains why the Ru(VIII) complex is not known. The ionic radii, IR(Hs8+)=0.454 Å for CN=4, IR(Os8+) = 0.49 Å and IR(Hs8+) = 0.54 Å for CN=6, have been obtained on the basis of the calculations of bond lengths in MO4, as well as via a correlation between R
max of the outer np obitals and IR of the 5d and 6d elements, respectively.
Sorption of U(VI) species on hydroxyapatite
Authors: Thakur P. , Moore R. C. , Choppin G. R. 
Published: August 2005

AbstractThe sorption of uranyl (UO22+) cations to hydroxyapatite was studied as a function of the amount of sorbent, ionic strength, U(VI) concentration, pH and temperature. The rate of uranyl sorption on hydroxyapatite decreased with increased uranyl concentrations. The amount sorbed decreased with increased ionic strength and increased with pH to a maximum at 7–8. The sorption data for UO22+were fitted well by the Freundlich and Dubinin–Radushkevich (D–R) isotherms. The anions Cl−, NO3−, SO42-and CH3COO−decreased the sorption of uranium on hydroxyapatite while S2O32-slightly increased it. The sorbed uranium was desorbed by 0.10 M and 1.00 M solutions of HCl and HNO3.The thermodynamic parameters for the sorption of UO22+were measured at temperatures of 298, 313, 323 and 333 K. The temperature dependence confirmed an endothermic heat of sorption. The activation energy for the sorption process was calculated to be +2.75±0.02 kJ/mol.
Synthesis and biodistribution of 99mTc-Vancomycin in a model of bacterial infection
Authors: Roohi Samina , Mushtaq A. , Malik Salman A. 
Published: August 2005

Abstract
Vancomycin Hydrochloride is an antibiotic produced by the growth of certain strains of Streptomyces orientalis. As Vancomycin Hydrochloride is poorly absorbed after oral administration; it is given intravenously for therapy of systemic infections. Vancomycin was labeled with technetium-99m pertechnetate using SnCl2·2H2O as reducing agent. The labeling efficiency depends on ligand/reductant ratio, pH, and volume of reaction mixture. Radiochemical purity and stability of 99mTc-Vancomycin was determined by thin layer chromatography. Biodistribution studies of 99mTc-Vancomycin were performed in a model of bacterial infection in Sprague–Dawley rats. A significantly higher accumulation of 99mTc-Vancomycin was seen at sites of S. aureus infected animals. Whereas uptake of 99mTc-Vancomycin in turpentine inflamed rats were quite low.
Prospects and problems in the production of 143Pr for radionuclide therapy applications
Authors: Vimalnath K. V. , Das M. K. , Venkatesh Meera , Ramamoorthy N. 
Published: August 2005

Abstract
Praseodymium-143 (T
1/2=13.57 d and E
β(max)= 0.937 MeV) is the beta decay product of 143Ce (T
1/2=33.04 h) and would provide an ideal complement to the widely used 32P (T
1/2= 14.3 d, E
β(max)=1.71 MeV), for some applications in radionuclide therapy (RNT), as it has a lower beta energy, but comparable half-life. For the production of 143Pr, 10-500 mg of two cerium compounds, ceric ammonium sulphate and ceric oxide, were irradiated in the reactor for 7 days at a neutron flux of ∼1×1013 n cm−2 s−1. After five days of post irradiation cooling, the samples were dissolved in appropriate reagents and aliquots drawn were subjected to high resolution gamma ray spectrometry for assay of activity and radionuclide purity. 7.4 MBq 143Ce per mg ceric oxide was produced under the aforesaid conditions along with other long-lived isotopes of cerium. An effort was made for the separation of no-carrier added (nca) 143Pr in order to study its utility for radionuclide therapy (RNT). A maximum yield of ∼450 MBq of 143Pr was obtained at calibration time defined as 7 d from end of irradiation (EOI). Hydroxyapatite (HA) was labeled with 143Pr at pH 5–6 and greater than 99.5% of 143Pr activity remained bound to HA even after 90 h post labeling. Despite the low cross-section of 142Ce(n,γ) reaction (0.1 barn) and isotopic abundance of 142Ce in natural targets (11.114%) being inherent disadvantages in large scale production of 143Pr, therapies needing low to medium doses would benefit from the use of ‘nca’ 143Pr.
Persistent diastolic dysfunction despite successful long-term octreotide treatment in acromegaly
Authors: van Thiel S W , Bax J J , Biermasz N R , Holman E R , Poldermans D , Roelfsema F , Lamb H J , van der Wall E E , Smit J W A , Romijn J A , Pereira A M 
Published: August 2005

Introduction: This study was designed to evaluate potential reversibility of left-ventricular (LV) dysfunction in patients with acromegaly following long-term control of disease. It is unknown whether the cardiac changes induced by acromegaly can be reversed completely by long-term strict control of growth hormone excess by octreotide.
Patients and methods: We compared LV systolic and diastolic function in inactive patients with acromegaly (n = 22), who were divided into patients with long-term control by octreotide (n = 14) and patients with long-term cure by surgery/radiotherapy (n = 8). We also assessed these parameters in patients with active acromegaly (n = 17).
Results: In patients with active acromegaly, systolic function at rest was decreased by 18% (P < 0.01), LV mass index increased by 40% (P < 0.04) and isovolumetric relaxation time increased by 19% (P < 0.01), compared with patients with inactive acromegaly. These parameters were not different between well-controlled and cured patients. Using tissue Doppler imaging, the ratio between early and late diastolic velocity (E′/A′ ratio) was decreased in active, compared with inactive acromegaly (0.75±0.07 versus 1.24±0.15; P < 0.01). This E′/A′ ratio was considerably higher in cured, compared with octreotide-treated, patients (1.75±0.41 versus 1.05±0.1; P < 0.01).
Conclusion: Diastolic function is persistently and significantly more impaired in acromegalic patients with long-term control by octreotide than in surgically cured patients, which points to biological effects of subtle abnormalities in growth hormone secretion. Criteria for strict biochemical control of acromegaly should thus be reconsidered.
Testosterone substitution with a new transdermal, hydroalcoholic gel applied to scrotal or non-scrotal skin: a multicentre trial
Authors: Kühnert B , Byrne M , Simoni M , Köpcke W , Gerss J , Lemmnitz G , Nieschlag E , _ _ 
Published: August 2005

Objective: Testosterone-containing gels have improved testosterone substitution therapy, but they are associated with the risk of interpersonal transfer. Therefore, we tested a new hydroalcoholic 2.5% testosterone gel (TGW), which was removed by washing 10 min after administration.
Design: The gel was applied to scrotal or non-scrotal skin in comparison to two 2.5 mg Androderm® patches in a randomised, three-arm, parallel-group, controlled multicentre trial over a period of 24 weeks. We included symptomatic hypogonadal men whose morning testosterone levels were <10 nmol/l. Either 1 g TGW was applied to scrotal skin (n = 54) or 5 g to non-scrotal skin (n = 56) once daily; the patch group (n = 52) applied two patches/day. Dose titration was allowed.
Results: Whereas serum testosterone levels and the pre-post changes of the areas under the curve of testosterone and free testosterone between weeks 0 and 24 indicated equivalent treatment success for the patch and scrotal groups, the dermal gel group was significantly superior to the other two groups. Questionnaires on sexual function, mood and quality of life did not differ significantly between study groups, nor were prostate volume, prostate-specific antigen (PSA) levels and prostate symptoms different. However, tolerability was much better in the gel groups than the patch group.
Conclusion: Efficacy, safety and tolerability suggest TGW as a favourable treatment for hypogonadal patients.
Polyethylene glycol-conjugated growth hormone-releasing hormone is long acting and stimulates GH in healthy young and elderly subjects
Authors: Munafo A , Nguyen T X Q , Papasouliotis O , Lécuelle H , Priestley A , Thorner M O 
Published: August 2005

Objective: The clinical use of growth hormone-releasing hormone (GHRH) is limited by its short half-life. Polyethylene glycol-conjugated GHRH (PEG-GHRH) was developed to provide increased stability compared with the currently available GHRH(1–29). This study aimed to evaluate the safety, tolerability and pharmacodynamics of PEG-GHRH.
Design: PEG-GHRH was administered by subcutaneous injection to young healthy men (n = 12) and elderly men and women (aged > 60 years; n = 20).
Results: In both groups, administration of PEG-GHRH generated a clear increase in circulating GH compared with placebo. Following single-dose (0.25, 0.5, 2 or 4 mg) administration to young subjects, the effect persisted for 12 h, but a sustained increase was observed on repeated administration to the elderly. Serum insulin-like growth factor-I also increased in response to PEG-GHRH treatment. Injection-site reactions were more frequent with PEG-GHRH compared with placebo, but these were mild and transient; other adverse events were similar to those observed after placebo. Some impairment of glucose tolerance was observed in the elderly following repeated administration of PEG-GHRH. Antibodies to GHRH were not observed.
Conclusions: PEG-GHRH offers the possibility of less frequent dosing compared with GHRH. This possibility deserves further clinical testing.
Duct ligation and pancreatic islet blood flow in rats: physiological growth of islets does not affect islet blood perfusion
Authors: Jansson Leif , Bodin Birgitta , Källskog Örjan , Andersson Arne 
Published: August 2005

Objectives: The aim of this study was to evaluate islet blood-flow changes during stimulated growth of the islet organ without any associated functional impairment of islet function.
Design: A duct ligation encompassing the distal two-thirds of the pancreas was performed in adult, male Sprague–Dawley rats.
Methods: Pancreatic islet blood flow was measured in duct-ligated and sham-operated rats 1, 2 or 4 weeks after surgery. In some animals studied 4 weeks after surgery, islet blood flow was also measured also during hyperglycaemic conditions.
Results: A marked atrophy of the exocrine pancreas was seen in all duct-ligated rats. Blood glucose and serum insulin concentrations were normal. An increased islet mass was only seen 4 weeks after surgery. No differences in islet blood perfusion were noted at any time point after duct ligation. In both sham-operated and duct-ligated rats islet blood flow was increased during hyperglycaemia; the response was, however, slightly more pronounced in the duct-ligated part of the gland.
Conclusions: Normal, physiological islet growth does not cause any major changes in the islet blood perfusion or its regulation. This is in contrast to findings during increased functional demands on the islets or during deteriorated islet function, when increased islet blood flow is consistently seen.