bluuebunny/crossref_metadata_2025_split huggingface dataset:
Superconducting Y–Ba–Cu–O Films with Tc&gt;70 K Prepared by Thermal Decomposition Technique of Y-, Ba-, and Cu-2ethylhexanoates
Authors: Nasu Hiroyuki , Makida Seigo , Kato Takeshi , Ibara Yoshikazu , Imura Takeshi , Osaka Yukio 
Published: July 2006

Abstract
High Tc superconducting Y–Ba–Cu–O films with Tc(end)&gt;70 K were prepared on yttria stabilized zirconia substrates by the thermal decomposition technique using Y-, Ba-, and Cu-2ethylhexanoates. The observed Tc(onset) was 95 K and Tc(end) was 72 K, and they are currently the highest Tc values for films obtained from organic acid salts.
The Synthesis of 2′,3′-Dideoxycytidine and Its 2′-Azido Analogue. Applications of the Deoxygenative [1,2]-Hydride Shift of Sulfonates with Mg(OMe)2–NaBH4
Authors: Kawana Masajiro , Yamasaki Noritsugu , Nishikawa Masahiro , Kuzuhara Hiroyoshi 
Published: July 2006

Abstract
New synthetic routes to the title compounds from cytidine were developed. Key intermediates were prepared by the deoxygenative reduction of 3′-O-mesylcytidine derivatives with the title reagents in a one-pot procedure.
Reactions of (η5-Cyclopentadienyl)(1,5-cyclooctadiene)cobalt(I), Diphenylacetylene, and a Mixture of S8 and Se8. Formation of (η5-Cyclopentadienyl)(1,2-diphenyl-2-selenolatoethylenethiolato-S,Se)cobalt(III) Complex
Authors: Kajitani Masatsugu , Ochiai Ryuji , Kobayashi Norikazu , Akiyama Takeo , Sugimori Akira 
Published: July 2006

Abstract
(η5-Cyclopentadienyl)(1,2-diphenyl-2-selenolatoethylenethiolato-S,Se)cobalt(III) (1) is formed in the reaction of CpCo(1,5-cyclooctadiene) (4), Ph–C≡C-Ph (5), and a mixture of S8 and Se8, together with the dithiolato and diselenolato complexes. A possible mechanism for the formation of 1 is the attack of 5 to some S,Se-mixed clusters which are formed in the reaction of 4 with Se8 and S8.
Efficiently Catalytic C–H Activation. Direct and Mild Carbonylation of Benzene and Cyclohexane by RhCl(CO)(PMe3)2 under Irradiation
Authors: Sakakura Toshiyasu , Tanaka Masato 
Published: July 2006

Abstract
A high turnover number was achieved in the photo-assisted carbonylation of C–H bonds of benzene catalyzed by RhCl(CO)(PMe3)2 under mild conditions (1 atm, 37 °C) to give mainly benzaldehyde. Cyclohexane could also be carbonylated under the same conditions.
Fluoride-promoted Epoxidation of α,β-Unsaturated Compounds
Authors: Miyashita Masaaki , Suzuki Toshio , Yoshikoshi Akira 
Published: July 2006

Abstract
The epoxidation of α,β-unsaturated compounds using tetrabutylammonium fluoride is described. This method has been demonstrated to be directly applicable to base-sensitive substrates such as cinnamaldehyde and α-phenylcinnamonitrile.
Michael Addition of Acetonitrile to Chalcones under Ultrasound Irradiation
Authors: Shibata Katsuyoshi , Urano Katsuyoshi , Matsui Masaki 
Published: July 2006

Abstract
When chalcones were treated with potassium superoxide (KO2) in acetonitrile under ultrasound irradiation, chalcone-acetonitrile adducts were obtained in moderate yields.
Superconductivity and Lattice Parameters in (La1−xSrx)2CuO4−δ Solid Solution System
Authors: Kanbe Shinsaku , Kishio Kohji , Kitazawa Koichi , Fueki Kazuo , Takagi Hidenori , Tanaka Shoji 
Published: July 2006

Abstract
The superconducting critical temperature TC increased with increase in x in (La1−xSrx)2CuO4−δ associated with the shortening of the Cu–O bond in the basal plane and the elongation of the lattice along the c-axis in the K2NiF4. structure. The results are discussed in terms of two-dimensional itinerant band formation of Cu:dx2-y2–O:pσ bond.
Cobalt Salts-Catalyzed Carbonylation of Aromatic Halides under Photostimulation
Authors: Kudo Kiyoshi , Shibata Tadashi , Kashimura Tsugunori , Mori Sadayuki , Sugita Nobuyuki 
Published: July 2006

Abstract
A novel method for the carbonylation of aromatic halides by the cobalt salt catalysts such as Co(OAc)2·4H2O, CoCl2·6H2O, CoSO4·7H2O, Co(OH)2, Co(OH)3, CoO,and Co2O3 was investigated in an aqueous alkaline solution under photostimulation. These salts were found to have a catalytic activity as high as that of Co2(CO)8 under mild conditions.
Preparation of New Solid Superbase and Its Catalytic Activity
Authors: Suzukamo Gohfu , Fukao Masami , Minobe Masao 
Published: July 2006

Abstract
A solid superbase whose basicity (H−) was higher than 37 was prepared by the successive treatment of γ-alumina with sodium hydroxide and sodium at 280–350 °C under nitrogen. The base was highly effective in the catalytic isomerization of 5-vinylbicyclo[2.2.1]hept-2-ene to 5-ethylidenebicyclo[2.2.1]hept-2-ene.
Synthesis of Peptides Containing α,α′-Iminodicarboxylic Acids
Authors: Yamada Takashi , Motoyama Noboru , Taniguchi Teiji , Kazuta Yasuaki , Miyazawa Toshifumi , Kuwata Shigeru , Matsumoto Kiyoshi , Sugiura Makiko 
Published: July 2006

Abstract
The peptides containing α,α′-iminodicarboxylic acids which are hardly prepared by the conventional methods of peptide synthesis, were well synthesized by the four-component condensation. The diastereomers were isolated, and their configurations were determined.
Transition-Metal Complex Catalyzed Perfluoroalkylation. A Facile Synthesis of Fluorine-Containing Esters by Carbo-Carbonylation of Alkynes and Alkenes
Authors: Urata Hisao , Yugari Hideki , Fuchikami Takamasa 
Published: July 2006

Abstract
Palladium-catalyzed reaction of perfluoroalkyl iodides with terminal alkynes or alkenes in alcohols under carbon monoxide pressure in the presence of potassium carbonate directly gives β-perfluoroalkyl-substituted alkenoates or alkanoates, respectively.
Stereoselective Selenolactonization by Superelectrophilic Benzeneselenenyl Triflate
Authors: Murata Shizuaki , Suzuki Toshiyasu 
Published: July 2006

Abstract
Benzeneselenenyl triflate is prepared from benzeneselenenyl chloride and silver trifluoromethanesulfonate. It performs selenium-induced cyclization of β,γ-, γ,δ-, and δ,ε-unsaturated carboxylic acids.
Selective Reduction of Aromatic Aldehyde in The Presence of Aromatic Ketone by NaBH4 and SnCl2 in THF
Authors: Ono Aoi , Hayakawa Hiroshi 
Published: July 2006

Abstract
Aromatic aldehydes were more selectively reduced to the corresponding alcohols than the related ketones by a reducing system consisting of NaBH4 and SnCl2 in THF in a common flask.
Synthesis of Optically Active Litsenolide C
Authors: Wakabayashi Shoji , Ogawa Hideki , Ueno Naomi , Kunieda Norio , Mandai Tadakatsu , Nokami Junzo 
Published: July 2006

Abstract
Lithium enolate, derived from alkyl 2-(phenylthio)alkanoate with lithium diisopropylamide, reacted with aldehyde in the presence of diethylaluminum chloride to give alkyl 2-phenylthio-2-alkyl-3-hydroxyalkanoate, which was converted to 2-alkylidene-3-hydroxy-alkanoate via thermolysis of the corresponding sulfoxide. The title compound was synthesized from methyl 2-(phenylthio)hexadecanoate and (R)-(+)-2-tert-butyldimethylsilyloxypropanal by employing the method.
Diacetonitrilebis(β-diketonato)ruthenium(II) Complexes. Their Preparation and Use as Intermediates for the Synthesis of Mixed-ligand β-Diketonato Ruthenium(III) Complexes
Authors: Kobayashi Tadashi , Nishina Yasuhiro , Shimizu Kunio , Satô Gen P 
Published: July 2006

Abstract
Diacetonitrilebis(β-diketonato)ruthenium(II) complexes were readily prepared by reducing the corresponding tris(β-diketonato)ruthenium(III) with zinc amalgam in an acetonitril–ethanol–water mixture. When a mixed-ligand β-diketonato complex [RuL2L′] is treated in this way, the more electron-donating ligand is preferentially displaced by two acetonitrile molecules. The diacetonitrile complexes are useful intermediates for the synthesis of mixed-ligand β-diketonato ruthenium( III) complexes of the type [RuL2L″].
Palladium-Catalyzed Reaction of Acyliron Complexes with Aryl Halides. A Convenient Synthesis of Aromatic Ketones
Authors: Koga Teruyoshi , Makinouchi Shinako , Okukado Nobuhisa 
Published: July 2006

Abstract
Acyliron complexes, easily prepared from disodium tetracarbonylferrate and alkyl halides, reacted with aryl iodides in the presence of a catalytic amount of Pd(PPh3)4 and a cocatalyst, ZnCl2, to give aromatic ketones in good yields. (R)-2-Methyl-1-phenyl-1-octanone was prepared starting from (S)-2-bromooctane in an excellent optical yield.
Synthesis of Poly(2,5-dimethoxy-p-phenylenevinylene) Film through a New Precursor Polymer
Authors: Momii Tatsuo , Tokito Shizuo , Tsutsui Tetsuo , Saito Shogo 
Published: July 2006

Abstract
Poly(2,5-dimethoxy-p-phenylenevinylene) was synthesized through a new precursor polymer. The new precursor polymer was soluble in organic solvents and chemically stable at room temperature.
Four New Metabolites Produced by Penicillium Citreo-viride B. on Addition of NaBr
Authors: Shizuri Yoshikazu , Shigemori Hideyuki , Sato Ryutaro , Yamamura Shosuke , Kawai Kazuaki , Furukawa Hideyuki 
Published: July 2006

Abstract
Four new metabolites (citreobiphenyl, precitreobiphenyl, citreoviranol, and demethylcitreoviranol) have been isolated from the mycelium of Penicillium citreo-viride B. (IFO 4692) incubated on the polished rice together with sodium bromide, and their structures have also been elucidated on the basis of their spectral data.
New Addition Reaction of Active Ester or Cyclic Ester with Epoxy Compounds Catalyzed by Insoluble Polystyrene-bound Quaternary Phosphonium or Ammonium Salts
Authors: Nishikubo Tadatomi , Shiina Atsushi , Isobe Naoki 
Published: July 2006

Abstract
Regioselective addition reaction of active ester S-phenyl thioacetate with 2-phenoxymethyloxirane was catalyzed by insoluble polystyrene-bound quaternary phosphonium or ammonium salts and gave 1-phenoxy-3-thiophenoxy-2-propyl acetate. Five-membered cyclic carbonates were also synthesized by the reaction of cyclic ester β- butyrolactone with some epoxy compounds using the same polymeric catalysts.
Photochemical Image Storage in Polymer Liquid Crystals
Authors: Ikeda Tomiki , Horiuchi Shin , Karanjit Durga B , Kurihara Seiji , Tazuke Shigeo 
Published: July 2006

Abstract
Amplified optical image storage has been demonstrated in polymer liquid crystals (PLC). A small amount (&lt; 5 mol%) of a low molecular weight mesogen with a photoresponsive moiety, 4-butyl-4′-methoxyazobenzene (BMAB), was doped in the films of polyacrylates with mesogenic side chain, poly(4′-methoxyphenyl-4-acryloyloxyalkoxybenzoate)(PAn), in which the alkyl spacer length (CH2)n was varied as n = 2, 3, 5, and 6. Photoirradiation of the PA3/BMAB film with a 366 nm light caused trans→cis isomerization of BMAB, which induced simultaneously the nematic (N)→isotropic phase transition of the PLC films. This photochemically induced phase transition was reversible and photoirradiation with a 525 nm light which induced cis→trans isomerization restored the system to the initial phase (N). The photo-induced phase transition was found to be strongly dependent on molecular weight of the host PLC and temperature.
Regioselective Nitration of Aromatic Hydrocarbons by Metallic Nitrates on the K10 Montmorillonite under Menke Conditions
Authors: Laszlo Pierre , Vandormael Joseph 
Published: July 2006

Abstract
Aromatic hydrocarbons are nitrated with good regioselectivities by clay-supported cupric nitrate in the presence of acetic anhydride. The procedure commends itself by its simplicity and gives useful yields (75–98%). In each case, the predominant product can be predicted by consideration of the Hückel HOMO for the aromatic ring.
An Efficient Synthesis of erythro-β-Hydroxy-l-histidine, the Pivotal Amino Acid of Bleomycin-Fe(II)–O2 Complex
Authors: Owa Takashi , Otsuka Masami , Ohno Masaji 
Published: July 2006

Abstract
erythro-β-Hydroxy-l-histidine is efficiently synthesized in organic solvents from the aldol reaction of (R)-3-bromoacetyl-4-isopropyl-1,3-oxazolidin-2-one and 1-triphenylmethylimidazole-4-carbaldehyde followed by SN2 reaction with LiN3 and hydrogenation.
Optical Resolution of Sulfoximines by Complex Formation with Optically Active 2,2′-Dihydroxy-1,1′-binaphthyl or 1,6-Di(o-chlorophenyl)-1,6-diphenylhexa-2,4-diyne-1,6-diol
Authors: Mori Koji , Toda Fumio 
Published: July 2006

Abstract
Some alkyl aryl and dialkyl sulfoximines were resolved efficiently by complex formation with optically active 2,2′-dihydroxy-1,1′-binaphthyl and 1,6-di(o-chlorophenyl)-1,6-diphenylhexa-2,4-diyne-1,6-diol, respectively.
In-Situ Scanning Tunneling Microscopy of Platinum Electrode in Sulfuric Acid
Authors: Itaya Kingo , Higaki Katsutoshi , Sugawara Shizuo 
Published: July 2006

Abstract
An in-situ scanning tunneling microscope (STM) was applied to clean Pt surfaces in aqueous sulfuric acid solutions. An electrochemical pretreatment was employed for a Pt electrode. It was suggested that the migration of ad-atoms of Pt produced by the oxidation and reduction cycles should occur towards a particular crystallographic direction.
Structure and Receptor Participation of Periplanone A, the Sex Pheromone of the American Cockroach
Authors: Nishino Chikao , Kobayashi Koji , Fukushima Masako , Imanari Mamoru , Nojima Kazutetsu , Kohno Shizue 
Published: July 2006

Abstract
Periplanones A (24 μg) and B (15 μg), the sex pheromones of the American cockroach, were isolated from the materials derived from 11500 females. The structure of periplanone A was elucidated to be (1Z,5E,7S*,10R*)-10(14)-epoxy-1,4(15),5-germacratrien-9-one. Either pheromone was revealed to participate with the corresponding sex pheromone receptor.
Synthesis and Chiral Recognition Property of 3-Acetylamino-3-deoxy-β-cyclodextrin
Authors: Murakami Teiichi , Harata Kazuaki , Morimoto Satoshi 
Published: July 2006

Abstract
Mono( 3-acetylamino-3-deoxy)-β-cyclodextrin (4) was firstly prepared via regioselective ring opening of manno-epoxide by ammonia. 1H-NMR investigation clearly demonstrated that 4 recognized the chirality of mandelic acids and N-acetyl-phenylglycine by the formation of diastereomeric inclusion complexes.
Valence States of Layered Vanadium Chalcogenophosphates, VPS3 and V0.78PS3
Authors: Ichimura Kenji , Sano Mizuka 
Published: July 2006

Abstract
VPS3 and V0.78PS3 have been synthesized by calcination of elementary mixtures prepared in the ratios of V:P:S = 1:1:3 and 0.78:1:3, respectively. Their X-ray diffraction patterns indicate that they have the same crystalline structure and orientation of crystal growth. The X-ray photoelectron spectra of V2p show that the vanadium in V0.78PS3 is in a mixed valence state and the compound is expressed by the formula of (V0.32+V0.73+)0.78PS3.
Hydrocarbons in the Yamato-791198 Carbonaceous Chondrite from Antarctica
Authors: Naraoka Hiroshi , Shimoyama Akira , Komiya Masatoshi , Yamamoto Hiroshi , Harada Kaoru 
Published: July 2006

Abstract
Yamato-791198 yielded up to 44 aromatic hydrocarbons and related compounds in the range of naphthalene and pyrene, including almost all structural isomers of methyl- and dimethyl-naphthalene. Several predominant compounds were present at the level of 10−7 g/g. Normal alkanes(C12−C22) were predominant in the aliphatic hydrocarbons and were at the level of 10−8 g/g.
Alumina-anchored Cobalt(II) Schiff Base Catalyst for the Isomerization of Trimethyldicyanoquadricyclane to the Norbornadiene
Authors: Miki Sadao , Maruyama Toshiro , Ohno Toshinobu , Tohma Toshihiko , Toyama Shin-ichi , Yoshida Zen-ichi 
Published: July 2006

Abstract
N,N′-Disalicylidene-4-carboxy-1,2-phenylenediiminatocobalt(II) supported on polyaminesulfone modified alumina beads has been prepared. The immobilized complex revealed efficient catalysis for the conversion of trimethyldicyanoquadricyclane (TMDC-Q) to the corresponding norbornadiene (TMDC-NBD). Using a bench-scale fixed bed reactor, TMDC-Q in chlorobenzene (1 mol dm−3) isomerized to TMDC-NBD quantitatively during the flow through catalyst bed of only 20 cm with the temperature increase from 24.5 °C to 75 °C.
Lithium-ion Insertion/Extraction Reaction with λ-MnO2 in the Aqueous Phase
Authors: Ooi Kenta , Miyai Yoshitaka , Katoh Shunsaku , Maeda Hiroshi , Abe Mitsuo 
Published: July 2006

Abstract
The topotactic insertion of Li+ in λ-MnO2 involved an evolution of oxygen and a reduction of Mn(lV) to Mn(III) in a (LiCl + LiOH) solution. The major reaction could be represented as λ-MnO2 + xLiOH → LixMnO2 + (x/2)H2O + (x/4)O2, where x denotes moles of inserted Li+ per mole of λ-MnO2. The extraction of the inserted Li+ was studied by using a solution containing either an acid(HCl) or an oxidizing agent(Br2, K2S2O8).
Maternal testosterone levels during pregnancy are associated with offspring size at birth
Authors: Carlsen S M , Jacobsen G , Romundstad P 
Published: July 2006

Objective: Animal studies have indicated that maternal androgen levels influence the intrauterine environment and development of the offspring. Human data are missing. We therefore investigated the possible association between maternal androgens and offspring size at birth in humans.
Design: A random sample of parous Caucasian women (n = 147) was followed prospectively through pregnancy.
Methods: Maternal serum levels of dehydroepiandrosterone sulfate (DHEAS), androstenedione, testosterone and sex hormone-binding globulin (SHBG) were measured at gestational weeks 17 and 33. The main outcome measures were weight and length at birth. Associations between maternal androgen levels and offspring birth weight and length were investigated using multiple linear regression modeling adjusted for potential confounding by maternal height, pre-pregnancy body mass index, smoking, parity, offspring gender and gestational age at birth.
Results: Elevated maternal testosterone levels at week 17 and 33 were both associated with lower birth weights and lengths. Accordingly, at week 17, an increase in maternal testosterone levels from the 25th to the 75th percentile was associated with a decrease in birth weight by 160 g (95% confidence interval (CI); 29–290 g), while at week 33 that estimate was 115 g (95% CI; 21–207 g). No similar associations were observed for DHEAS, androstenedione or SHBG.
Conclusions: Elevated maternal testosterone levels during human pregnancy are associated with growth restriction in utero. Our results support animal studies, which have indicated that maternal androgen levels influence intrauterine offspring environment and development.
Frequency of the metabolic syndrome in obese Spanish pediatric population
Authors: López-Capapé Marta , Alonso Milagros , Colino Esmeralda , Mustieles Carmen , Corbatón José , Barrio Raquel 
Published: July 2006

Objective: Obesity is associated with insulin-resistance (IR), type 2 diabetes (T2D) and a constellation of cardiovascular risk factors at the early years of life. These features define the so-called metabolic syndrome (MS).
Aims: To assess the frequency of the MS among obese pediatric Spanish population and analyse the individual contribution and the predictive potential of individual components to the development of the syndrome.
Patients and methods: A total of 429 patients, 220 boys and 209 girls, aged 4–18 years, with a body mass index of > 2 standard deviation scores for Spanish normative charts, were included in the study. Forty-seven percent were prepubertal and ten percent had Hispanic ethnicity. HbA1c, lipids, liver enzymes and uric acid levels were determined from blood and a standard 2-h oral glucose tolerance test was performed. MS was defined by the National Cholesterol Education Program’s Adult Treatment Panel III criteria modified by Cook as having at least three features among: obesity, low high-density lipoprotein (HDL), hypertriglyceridemia, hypertension (HTA) or impaired glucose metabolism (IGM). We defined IR as homeostatic model assessment of IR index and/or fasting insulin levels> 95th centile of the control population.
Results: Almost 18% of the patients had MS, with significantly higher frequency in Hispanic (32%) than in Caucasian (16%) population. There were no differences by sex or pubertal status. Prevalence of low HDL, HTA, hypertriglyceridemia and IGM were 27, 23, 16 and 7% respectively. No silent T2D was identified. According to International Obesity Task Force charts, 22% of the patients were overweight and not obese, but no differences in the frequency of individual features of MS between these two groups were observed. Among IR patients (35% of our population), the frequency of MS reached 28%. IR predicted the presence of MS independently from age and race.
Conclusion: MS is present in 18% of our obese pediatric population. IR is closely associated with the components of MS and strongly predicts its development.
The Danish investigation on iodine intake and thyroid disease, DanThyr: status and perspectives
Authors: Laurberg Peter , Jørgensen Torben , Perrild Hans , Ovesen Lars , Knudsen Nils , Pedersen Inge Bülow , Rasmussen Lone B , Carlé Allan , Vejbjerg Pernille 
Published: July 2006

Objective: Denmark was an area of iodine deficiency, and mandatory iodine fortification of table salt and salt in bread (13 p.p.m. iodine) was initiated in 2000/2001. The Danish investigation on iodine intake and thyroid disease (DanThyr) is the monitoring of the iodine fortification program.
Design and methods: DanThyr consists of three main parts: a study of population cohorts initialized before (n = 4649) and after (n = 3570) iodization of salt, a prospective identification of incident cases of overt hyper- and hypothyroidism in a population of around 550 000 people since 1997, and compilation of data from the national registers on the use of thyroid medication, thyroid surgery, and radioiodine therapy. Studies were carried-out in parallel in subcohorts living in areas with differences in iodine content of ground water.
Results: The study showed profound effects of even small differences in iodine intake level on the prevalence of goiter, nodules, and thyroid dysfunction. Mild and moderate iodine deficiency was associated with a decrease in serum TSH with age. Other environmental factors were also important for goiter development (increase in risk, smoking and pregnancy; decrease in risk, oral contraception and alcohol consumption), and the individual risk depended on the genetic background. Environmental factors had only a minor influence on the prevalence of thyroid autoantibodies in the population. There were more cases of overt hypothyroidism in mild than in moderate iodine deficiency caused by a 53% higher incidence of spontaneous (presumably autoimmune) hypothyroidism. On the other hand, there were 49% more cases of overt hyperthyroidism in the area with moderate iodine deficiency. The cautious iodine fortification program, aiming at an average increase in iodine intake of 50 μg/day has been associated with a 50% increase in incidence of hyperthyroidism in the area with the most severe iodine deficiency. The incidence is expected to decrease in the future, but there may be more cases of Graves’ hyperthyroidism in young people.
Conclusion: A number of environmental factors influence the epidemiology of thyroid disorders, and even relatively small abnormalities and differences in the level of iodine intake of a population have profound effects on the occurrence of thyroid abnormalities. Monitoring and adjustment of iodine intake in the population is an important part of preventive medicine.