bluuebunny/crossref_metadata_2025 huggingface dataset:
Effectiveness of strategies to recruit underrepresented populations into cancer clinical trials
Authors: Lai Gabriel Y , Gary Tiffany L , Tilburt Jon , Bolen Shari , Baffi Charles , Wilson Renee F , Howerton Mollie W , Gibbons M Chris , Tanpitukpongse Teerath Peter , Powe Neil R , Bass Eric B , Ford Jean G
Published: May 2006

Background Certain populations, including racial and ethnic minorities and older persons, have had a history of low participation in cancer-related trials, yet there has been little information reported on recruitment strategies tailored to improve their enrollment.

Methods We conducted a systematic literature review to examine the methods used to study recruitment of underrepresented populations into cancer prevention and treatment trials and examined the studies that compared the efficacy and/or effectiveness of different recruitment strategies. We performed an electronic search through multiple databases including PubMed and a hand search of 34 journals. Potential studies were pulled and underwent title, abstract, and article review by at least two investigators.

Results Fourteen articles examined recruitment of underrepresented populations into cancer trials and, of these, five compared efficacy or effectiveness of different strategies for recruitment of underrepresented populations into randomized or concurrent controlled trials. These five studies used various strategies but only three reported that specific recruitment strategies, such as media campaigns and churchbased project sessions, resulted in improvement in accrual to cancer trials.

Conclusion There is limited evidence for efficacious or effective strategies to recruit underrepresented populations in cancer-related trials. The available evidence cannot be generalized to these heterogeneous groups. Further study is needed on efficacious strategies for recruitment of underrepresented populations into cancerrelated trials.
Listen to all the voices: an advocate's perspective on early access to investigational therapies
Authors: Mayer Musa
Published: May 2006

In this issue of the journal, The Society for Clinical Trials, whose members are clinical investigators and regulators in academia, government and industry, has published the rationale for their opposition to US Senate bill S. 1956, the socalled “ACCESS” act, which would allow the marketing of therapies that have undergone only Phase I studies (dose finding and toxicity testing) in humans, to patients with “serious and life-threatening” disease who have exhausted other treatment options. While this bill reflects the views and efforts of some cancer advocates and their supporters, it does not represent the beliefs of the cancer advocacy community overall. The essay that follows is inspired by the need for other voices from the patient and advocacy communities to be heard in this debate.
Revolution and Nostalgia: American Elegies for British Empire
Authors: Tamarkin Elisa
Published: May 2006

Elisa Tamarkin is assistant professor of English at the University of California, Irvine. She is completing a book, American Anglophilia: Deference, Devotion, and Antebellum Culture.
Body, Earth, and Migration: The Poetics of Suffering in Zhang Wei's September Fable
Authors: Xu Jian
Published: May 2006

Jian Xu is assistant professor of comparative literature at the University of Wisconsin at Milwaukee. His article “Representing Rural Migrants in the City: Experimentalism in Wang Xiaoshuai's So Close to Paradise and Beijing Bicycle” appeared in the Winter 2005 issue of Screen.
Walking byIxodes ricinusticks: intrinsic and extrinsic factors determine the attraction of moisture or host odour
Authors: Crooks Emily , Randolph Sarah E.
Published: May 2006

Spontaneous walking by Ixodes ricinus nymphs in the horizontal plane was investigated within choice arenas to test whether these ticks move preferentially up a humidity gradient, and whether they are attracted towards host odour, specifically volatile substances from the back of a dog's ear. Responses by ticks with high and low fat contents and in different states of hydration were compared. Ticks with higher energy reserves were more likely to walk horizontally over short distances. Only if they were slightly dehydrated were they more likely to walk towards fully saturated air than drier air, and only if the atmosphere was sufficiently wet were they likely to walk towards odour secreted by host skin. It seems that, under certain circumstances, ticks of this ambushing species will move short distances towards host odour.
Temperature Dependence of Mixed-Valence States in Solvated and Non-Solvated Trinuclear Iron Stearates
Authors: Nakamoto Tadahiro , Katada Motomi , Sano Hirotoshi
Published: May 2006

Solvated and non-solvated mixed-valence trinuclear iron stearates were prepared and their Mössbauer spectra were determined. XRD patterns of the compounds show that they have layer structures having different inter-layer distances. A temperature-dependent mixed-valence state was observed in the non-solvated compound, while not in the solvated compound.
Allyltris(trimethylsilyl)silane as Radical Allylating Agent for Organic Halides
Authors: Kosugi Masanori , Kurata Hiroshi , Kawata Ken-ichi , Migita Toshihiko
Published: May 2006

Reaction of allyltris(trimethylsilyl)silane with organic halides under the free radical conditions resulted in allylation of the halides in modrate to good yields. The presence of three trimethylsilyl groups on the silicon could enhance the homolytic dissociation of a Si–C bond in the β-silylalkyl radical.
Oxidation of Uranium(IV) by Nitrite Ion in Dimethyl Sulfoxide. Evidence of Direct Oxygen Transfer Mechanism
Authors: Park Yoon-Yul , Ikeda Yasuhisa , Harada Masayuki , Tomiyasu Hiroshi
Published: May 2006

The oxidation of [U(dmso)8]4+ (dmso = dimethyl sulfoxide) by nitrite ion was studied in dmso. The reaction was found to proceed via two steps: the first step was the rapid formation of 1 : 2 complex between U(IV) and nitrite ion, and the second one the intramolecular oxygen transfer reaction from nitrite to U(IV). The latter step was confirmed by oxygen labeled experiments using 17O-NMR.
Unexpected Thermal Rearrangement of N-[1-Methyl-6-(methoxycarbonyl)-5-hexynylidene]methylamine N-Oxide
Authors: Kang Han-Young , Cho Yong Seo , Koh Hun Yeong , Chang Moon Ho
Published: May 2006

N-[1-Methyl-6-(methoxycarbonyl)-5-hexynylidene]methylamine N-oxide, a ketonitrone which was prepared from the reaction between methyl 7-oxooct-2-ynoate and N-methylhydroxylamine rearranged thermally into two isomeric bicyclic compounds instead of the expected intramolecular [3+2] cycloadduct. Also an aldonitrone, N-[6-(methoxycarbonyl)-5-hexynylidene]methylamine N-oxide provided the corresponding rearranged product.
Photoinduced Electron-Transfer Reaction in a Zinc Myoglobin–Hexacyanoferrate(III) Complex
Authors: Tsukahara Keiichi , Asami Satoko
Published: May 2006

The photoinduced electron transfer was observed in a zinc myoglobin–hexacyanoferrate(III) complex, which forms by electrostatic interactions, and was inhibited in addition of poly-L-lysine by forming a stable complex of poly-L-lysine and hexacyanoferrate(III) ions.
The Asymmetric Diels–Alder Reaction of α,β-Unsaturated Aldehydes with Dienes Using a Chiral Boron Reagent as a Catalyst
Authors: Kobayashi Shu , Murakami Masatoshi , Harada Tsunehiro , Mukaiyama Teruaki
Published: May 2006

The asymmetric Diels–Alder reaction of α,β-unsaturated aldehydes with cyclopentadiene is catalyzed by a novel chiral boron reagent generated in situ from boron tribromide and a chiral prolinol derivative, to afford the corresponding adducts in good yields with fairly good to excellent ees.
Synthesis and Structural Analysis of Dimethoxy[2.n]metacyclophanes
Authors: Okada Yukihiro , Mabuchi Shunsuke , Kurahayashi Masaki , Nishimura Jun
Published: May 2006

Dimethoxy[2.n]metacyclophanes were obtained in 46–68% yields through [2 + 2] photocycloaddition of corresponding styrene derivatives. These metacyclophanes were assigned to be of syn-conformation (n = 3, 4, 5, and 6) or the mixture of syn- and anti-conformers with the syn/anti ratio of 4/3 (n = 2).
Facile Synthesis of α-Hydroxybutenolides and α-Keto-β-allyl-γ-butyrolactones
Authors: Shimizu Isao , Maruyama Takashi , Hasegawa Hajime
Published: May 2006

The reaction of α-keto-β-alkyl-β-allyloxycarbonyl-γ-butyrolactones with ammonium formate in the presence of palladium catalyst gave α-hydroxybutenolides in good yields. When the reaction was carried out without ammonium formate, decarboxylation-allylation took place to give allyl enol ethers of α-hydroxybutenolides, which were converted to α-keto-β-allyl-γ-butyrolactones by the thermal Claisen rearrangement.
Alignment of Liquid Crystal on the Conductive Pyrolyzed Polyimide Langmuir–Blodgett Films
Authors: Akatsuka Takahisa , Tanaka Hideaki , Toyama Jiro , Nakamura Takayoshi , Matsumoto Mutsuyoshi , Kawabata Yasujiro
Published: May 2006

Highly conductive pyrolyzed polyimide Langmuir–Blodgett (LB) films showed good aligning properties for a twisted nematic liquid crystal. Static and dynamic alignment properties of the LB films were similar to those of rubbed polyimide films on ITO electrodes.
Synthesis of Benzo[c]quinolizinium Salts by Photocyclization
Authors: Arai Sadao , Tabuchi Kunihisa , Arai Hitoshi , Yamagishi Takamichi , Hida Mitsuhiko
Published: May 2006

The photocyclization of 2-[2-(2-chlorophenyl)vinyl]-6-methylpyridine and 2-[2-(2-chlorophenyl)vinyl]quinoline in acetonitrile afforded new compounds 1-methylbenzo[c]quinolizinium salt and dibenzo[c,f]quinolizinium salt in 56% and 41% yields, respectively.
Reactions of Ethynylcarbenes Related to Solid-State Polymerization of 1-Phenyl-1,3-butadiyne
Authors: Koga Noboru , Matsumura Masahiro , Noro Masaki , Iwamura Hiizu
Published: May 2006

1,8-Diphenyl-1,8-bis(diazo)-octa-4-ene-2,6-diyne was prepared and photolyzed to give 1-phenyl-1,3-butadiyne in high yield. Ethynylphenylcarbene and β-phenylethynylcarbene generated by photolysis in MTHF at 6 K are in equilibrium in which the latter predominates at 90 K.
Synthesis and Radical Polymerization of Adamantyl-Containing Maleic and Fumaric Esters Leading to Formation of Thermally Stable Poly(substituted methylene)s with a Rigid Chain Structure
Authors: Matsumoto Akikazu , Otsu Takayuki
Published: May 2006

Several dialkyl maleates and fumarates bearing 1-adamantyl and 3,5-dimethyl-1-adamantyl groups were prepared and polymerized with a radical initiator, resulting in formation of high molecular weight and thermally stable poly(substituted methylene)s with a rigid chain structure.
A New and Stereoselective Synthetic Route to an Amaryllidaceae Alkaloid, (±)-Lycorine
Authors: Hoshino Osamu , Ishizaki Miyuki , Kamei Keisuke , Taguchi Minoru , Nagao Takashi , Iwaoka Kiyoshi , Sawaki Shohei , Umezawa Bunsuke , Iitaka Yoichi
Published: May 2006

Formal and total syntheses of an Amaryllidaceae alkaloid, (±)-lycorine, were achieved by a new synthetic route via (±)-3-(phenylseleno)-seco-dihydro-B-norlycorin-5-one.
Induction of Left-Handed Helical Arrangement of 4-Nitrobenzyl Ester Residues in Cast Film from Poly(L-Glutamate) by Using a Cationic Bilayer Forming Compound
Authors: Hirayama Chuichi , Ihara Hirotaka , Shiraga Ryuichi
Published: May 2006

Poly(γ-4-nitrobenzyl L-glutamate) provided S-chirality with strong exciton coupling in cast film by using dihexadecylammonium bromide (2C16N+2C1) as an additive. The X-ray and IR spectra showed that the main chain formed helices. The addition of 2C16N+2C1 induced a left-handed helical conformation of the main chain, along which the chromophoric residues were helically arranged.
Chemiluminescence of Tryptophan with Electrogenerated Tris(2,2′-bipyridine)ruthenium(III)
Authors: Uchikura Kazuo , Kirisawa Makoto
Published: May 2006

A system for electrogenerated chemiluminescence based on the reaction of electrogenerated Ru(bpy)33+ with tryptophan (Trp) is described. The orange chemiluminescence was generated by reaction of Ru(bpy)33+ with Trp in acidic solution. The lowest detection limit was 0.1 pmol for Trp. This newly demonstrated system should prove useful for the selective and sensitive detection of Trp.
α-Methylene Cyclic Carbonate as a Conjunctive Agent for Aromatic Aldehydes
Authors: Inoue Yoshio , Matsushita Koichi , Yen I-Fang , Imaizumi Shin
Published: May 2006

α-Methylene cyclic carbonate underwent decarboxylative cycloaddition to aromatic aldehydes to yield dihydrofuranone derivatives in the presence of a dicationic palladium complex.
A Convenient Route for the Synthesis of 2-C-Substituted 2-Deoxyhexoses
Authors: Sugimura Hideyuki , Osumi Kenji , Koyama Tatsuyuki
Published: May 2006

A facile method has been developed for the synthesis of 2-C-substituted 2-deoxy-D-glucoses and 2-C-disubstituted 2-deoxy-D-arabino-hexoses using the BF3-catalyzed cyclization between 1-alkenyl ethers and 2,3-O-isopropylidene derivative of aldehydo-D-erythrose.
Synthesis and Properties of Optically Active α-Aryl-γ-alkyl-γ-lactones as Chiral Dopants for Ferroelectric Liquid Crystals
Authors: Sakaguchi Kazuhiko , Kitamura Tohru , Shiomi Yutaka , Koden Mitsuhiro , Kuratate Tomoaki
Published: May 2006

Optically active α-aryl-γ-alkyl-γ-lactones were synthesized from chiral epichlorohydrin in several steps and found to be good chiral dopants for ferroelectric liquid crystals (FLCs). Relationship between molecular structures and properties is discussed.
Crystalline Complexes of Acyclic p-Cresol-Formaldehyde Tetramer with Benzene. An Induced Fit Type Binding of Benzene Molecule
Authors: Usui Shuji , Deyama Kazuhito , Fukazawa Yoshimasa , Sone Tyo , Ohba Yoshihiro
Published: May 2006

An acyclic p-cresol-formaldehyde tetramer (1) has syn-anti arrangement of cresol units and forms “partial cone” type cavity. A benzene is included in the cavity composed of the two facing partial cones. While 1 forms cyclic dimer via intra- and intermolecular hydrogen bondings, its dibromo derivative forms acyclic dimer with anti-anti arrangement of cresol units.
Solid-State Organic Reactions Proceeding by Pulverization of Inorganic Solid-Supports. Reactions of lodosobenzene with Unsaturated Hydrocarbons on Acid-Treated Silica Gel
Authors: Sohmiya Hajime , Kimura Takahide , Bauchat Patrick , Fujita Mitsue , Ando Takashi
Published: May 2006

Pulverization of solid mixtures of hydrogen halide-treated silica gels, iodosobenzene, and alkenes or an alkyne in the absence of a solvent brings about smooth and rapid reaction to give halogenated or oxidized products in good yields.
Synthesis and Magnetic Property of Imidazolate-Bridged Trinuclear Cu(II)–Fe(III)–Cu(II) Complexes. Effect of Fe(III) Spin-State Upon Spin-Coupling
Authors: Matsumoto Naohide , Tamaki Hiroko , Inoue Keiji , Koikawa Masayuki , Maeda Yonezo , Okawa Hisashi , Kida Sigeo
Published: May 2006

Imidazolate-bridged trinuclear Cu(II)–Fe(III)–Cu(II) complexes [Cu(A)Fe(acen)Cu(A)]ClO4·2H2O (1) and [Cu(A)Fe(salen)Cu(A)]ClO4·2H2O (2) are synthesized and characterized by magnetic susceptibilities, Mossbauer spectra, and ESR spectra, where H2A = 4-(6-methyl-8-oxo-2,5-diazanonane-1,5,7-trienylimidazole. The Fe(III) of 1 is in low-spin state (S = 1/2) and the spin-coupling between the Fe(III) and Cu(II) ions is ferromagnetic. On the other hand, the Fe(III) of 2 is in high-spin state (S = 5/2) and the spin-coupling is antiferromagnetic.
Cobalt-Catalyzed Photochemical Carbonylation of Allylic Amines
Authors: Mori Sadayuki , Matsuyoshi Hiroaki , Kudo Kiyoshi , Sugita Nobuyuki
Published: May 2006

Allylic amines are carbonylated at room temperature in the presence of cobalt catalysts under UV irradiation. With allylamine, 2-pyrrolidone, N,N′-diallylurea, and N-allyl-3-butenamide were obtained. The photochemical cleavage of C–N bond of amines coordinated to cobalt metals was suggested.
Unusual Differences between the Average Mn–Se and Mn–S Distances and between Se–C and S–C Distances in (NMe4)2[Mn(QPh)4] (Q = Se, S)
Authors: Ueyama Norikazu , Kajiwara Atsushi , Yasuoka Noritaka , Nakamura Akira
Published: May 2006

Crystal structures of (NMe4)2[MnII(SePh)4] and (NMe4)2[MnII(SPh)4]were determined to compare their structures, properties and catalytic activities. Both complexes have a tetrahedral geometry of MnSe4 or MnS4 core. An unusual difference (0.22 Å) between Mn–Se and Mn–S distances, and a large difference (0.22 Å) between Se–C and S–C were found, compared with those (0.11 Å and 0.15 Å, respectively) in (NMe4)2[MII(QPh)4] (M = Cd, Zn; Q = Se, S). The differences are ascribed to the stronger Mn–S π-bonding character than those of Cd–S, Zn–S and Fe–S.
Substituent Effects on the Formal Potential of the CoII/CoIII Redox Couple for Co(salen) Derivatives
Authors: Nishinaga Akira , Tajima Kunihiko , Speiser Bernd , Eichhorn Emerich , Rieker Anton , Ohya-Nishiguchi Hiroaki , Ishizu Kazuhiko
Published: May 2006

The formal potential of the CoII/CoIII redox couple in Co(salen) derivatives determined in DMF varies with the electronic as well as the steric properties of substituents at the aromatic rings in the salen ligand, where t-butyl groups shift the potential to more positive values, indicating strong steric interactions with solvent molecules.
Stereoselective Reduction of Enamino Sulfoxides
Authors: Ogura Katsuyuki , Tomori Hiroshi , Fujita Makoto
Published: May 2006

Enamino sulfoxides, p-TolS(O)CH=C(NR1R2)R (where R1 = alkyl, R2 = H or alkyl), were reduced with lithium tri(s-butyl)borohydride or borane·THF, respectively, to give β-amino sulfoxides of R*,R* configuration with high stereoselectivity.
Determination of Ethanol in Aqueous Solutions Using a Fiber-Optic Sensor with a Chitosan/Poly(vinyl alcohol) Cladding
Authors: Kurauchi Yoshiaki , Yanai Takayuki , Ohga Kazuya
Published: May 2006

Ethanol in aqueous solutions was determined by the use of an optical fiber with a cladding composed of chitosan and poly(vinyl alcohol). The response time of the probe for 50 v/v% ethanol was about 1 min and the relative standard deviation of the reproducibility was below 3% (n = 40).
Rearrangement of Allylic and Propargylic Alcohols Catalyzed by the Combined Use of Tetrabutylammonium Perrhenate(VII) and p-Toluenesulfonic Acid
Authors: Narasaka Koichi , Kusama Hiroyuki , Hayashi Yujiro
Published: May 2006

Allylic rearrangement and/or dehydration of allylic alcohols proceed by the use of a catalytic amount of tetrabutylammonium perrhenate and p-toluenesulfonic acid. Treatment of propargylic alcohols with the above reagents affords the rearranged products, α,β-unsaturated carbonyl compounds.
Thermolyses of Hexakis(trimethylsilyl)benzene and Pentakis(trimethylsilyl)toluene. The First Unique Trimethylsilyl-Triggered Rupture of Benzene Rings
Authors: Sekiguchi Akira , Ebata Keisuke , Terui Yoriko , Sakurai Hideki
Published: May 2006

Thermolysis of highly distorted hexakis(trimethylsilyl)benzene and pentakis(trimethylsilyl)toluene resulted in the formation of products arising from the ruptures of the aromatic rings.
Fluorination of Chlorinated Trifluoromethyl Ethers
Authors: Sekiya Akira , Ueda Kunimasa
Published: May 2006

Chlorine atoms in the chlorinated trifluoromethyl ether prepared from the reaction between chlorinated ethylenes and trifluoromethyl hypofluorite were fluorinated directly by fluorine gas. Tin(II) fluoride/sodium fluoride system was effective in the fluorination.
Synthesis of 2-Bis(trifluoromethyl)hydroxymethyl Substituted Cyclic Amines through Novel Intramolecular Substitution of an Arylsulfonyl Group
Authors: Taguchi Takeo , Suda Yoshimitsu , Hamochi Masahiko , Fujino Yasuhiro , Iitaka Yoichi
Published: May 2006

ω-Amino-1,1-bis(trifluoromethyl)-2-sulfonyl-1-pentanol or -hexanol provided the corresponding pyrrolidine or piperidine having BTHM group at the 2-position via intermediary epoxide by treating with NaOH in the presense of phase-transfer catalyst.
Synthesis and Characterization of Novel Tetranuclear and Binuclear Manganese(III) Complexes with 1,5-Bis(salicylideneamino)-3-pentanol
Authors: Mikuriya Masahiro , Yamato Yo , Tokii Tadashi
Published: May 2006

Tetranuclear and binuclear manganese(III) complexes with 1,5-bis(salicylideneamino)-3-pentanol (H3L), [Mn4(L)2(O)2(CH3COO)2]·4H2O·2CH3OH and [Mn2(L)(CH3O)(NCO)2(H2O)2], have been prepared and characterized by X-ray structure analysis and magnetic susceptibilities (80–300 K).
Pd-Catalyzed Regie- and Stereo-selective Carboxylation of Cycloalkanes with CO
Authors: Satoh Ko-ichi , Watanabe Jun , Takaki Ken , Fujiwara Yuzo
Published: May 2006

The reactions of cycloalkanes with CO via the C–H bond activation by Pd(OAc)2 catalyst have been found to proceed regio- and stereo-selectively to give corresponding carboxylic acids. The reactivity of C–H bonds of cycloalkanes decreases in the order: tert- > sec- > prim-carbon, and the stereochemistry of the substituents on the main products is all equatorial.
Palladium Catalyzed Carboxylation of Cyclohexane with Carbon Monoxide
Authors: Nakata Kazuyuki , Watanabe Jun , Takaki Ken , Fujiwara Yuzo
Published: May 2006

Very high turnover numbers of the catalyst in direct carboxylation of cyclohexane with CO have been obtained using palladium catalyst, to give 8.8% yield (turnover number 205) of cyclohexanecarboxylic acid based on the starting alkane.
Synthesis of 6-Deoxy-4-O-methyl-6-phenylphosphinyl-D-fructopyranoses. The First P-in-the-Ring Analogs of a Ketose
Authors: Hanaya Tadashi , Okamoto Ryuji , V. Prikhod’ko Yurij , Yamamoto Hiroshi
Published: May 2006

Treatment of D-fructose with 2-methoxypropene–TsOH, followed by tosylation, gave 1,3-O-isopropylidene-6-O-tosyl-α-D-fructofuranose (5). Methyl 6-deoxy-6-[(ethoxy)phenylphosphinyl]-4-O-methyl-α-D-fructofuranoside (8) was derived from 5 in a 3 step sequence (67% overall yield). Compound 8 was converted into the title compounds, which were characterized as the 1,3,5-tri-O- and 1,2,3,5-tetra-O-acetyl derivatives.
Stereospecific One-pot Synthesis of Enamides and Enimides by the Copper Iodide Promoted Vinylic Substitution
Authors: Ogawa Takuji , Kiji Toshiyuki , Hayami Kazuo , Suzuki Hitomi
Published: May 2006

Enamides and enimides were prepared stereospecifically from vinyl bromides by direct vinylic substitution in the presence of copper salt in aprotic polar solvents.
Ytterbium Tricyanide, a Highly Efficient Catalyst for the Addition of Cyanotrimethylsilane to Carbonyl Compounds
Authors: Matsubara Seijiro , Takai Tsutomu , Utimoto Kiitiro
Published: May 2006

Reaction of cyanotrimethylsilane with various carbonyl compounds was effectively catalyzed by Yb(CN)3 to give the adducts in excellent yields; reaction with substituted cyclohexanones proceeded in a highly stereoselective manner.
An Ordering of Complexation Ability for a Series of Permethylated Aldopyranoses with Metal Cations in Solution. 1H-NMR Relaxation Probes
Authors: Takai Yoshio , Shizuma Motohiro , Okumura Yasuo , Hidaka Yukio , Hanafusa Terukiyo , Takahashi Shigetoshi , Sawada Masami
Published: May 2006

By using 1H-NMR relaxation technique, an ordering of complexation ability for a series of permethylated aldopyranoses with metal cations in solution has been determined, which is identical with that of the peak-intensity for the 1:1 adduct ions by FAB mass spectrometry.
Site-Selective Photocyclization of Acetylglycine–Anthraquinone Molecules
Authors: Maruyama Kazuhiro , Hashimoto Masakazu , Tamiaki Hitoshi
Published: May 2006

5-[(N-Acetylglycyl)amino]pentyl, 5-[(N-acetylglycyl-α-methylalanyl)amino]pentyl, and 5-[(N-acetylglycyl-α-methylalanyl-α-methylalanyl)amino]pentyl anthraquinone-2-carboxylate underwent a photocyclization in an acetonitrile solution to produce efficiently large-sized ring-closure compounds as isolable products. In the photocyclization, high site-selectivity in the carbonyl groups of anthraquinone moiety was first observed.
Synthesis of γ-Lactones by the Intramolecular Radical Cyclization of 2-Bromo-3,3-bis(methylthio)propionates. A Useful Ketene Radical Synthon
Authors: Iwasa Seiji , Yamamoto Makoto , Furusawa Atsuko , Kohmoto Shigeo , Yamada Kazutoshi
Published: May 2006

The first example of intramolecular radical cyclization of ketene radical synthon is presented. Intramolecular radical cyclization of 2-bromo-ketene-S,S-acetals proceeded highly regioselectively to give the corresponding 5-exo-trig cyclized γ-lactones.
Synthesis and Properties of [2.2](3,5)- and [2.2.2.2](3,3′,5,5′)-Diphenoquinonophanes
Authors: Tani Keita , Takano Junji , Tohda Yasuo , Ariga Masahiro , Higuchi Hiroyuki , Misumi Soichi
Published: May 2006

The first synthesis and the physical properties of diphenoquinonophanes is reported along with their spectral evidences.
Novel Preparation Method of Manganese(II) Manganese(IV) Oxide(Mn2Mn3O8, Mn5O8) by Citrate Process
Authors: Sugawara Michio , Ohno Masamichi , Matsuki Kenzo
Published: May 2006

The amorphous citrate precursor obtained by the reaction of manganese nitrate and citric acid resulted in the formation of single phase of Mn5O8 by the thermal decomposition at 300–400 °C in oxygen atmosphere.
A Novel Reagent for the Synthesis of Branched-chain Functionalized Sugars. Dichloromethyllithium
Authors: Sato Ken-ichi , Suzuki Katsuhiko , Ueda Miyuki , Katayama Masaftimi , Kajihara Yasuhiro
Published: May 2006

A few novel branched-chain functionalized sugars, which have important functions such as hydroxyl, hydro, chloro, or azido at quaternary carbon were prepared in good yield via the same intermediary spiro chloroepoxide derivative by use of dichloromethyllithium.
Synthesis of Optically Active 2,3,6-Tri-O-benzyl-D-myo-inositol from D-Glucose
Authors: Sato Ken-ichi , Sakuma Shogo , Muramatsu Shinya , Bokura Masayuki
Published: May 2006

The title compound was synthesized from D-glucose as a key intermediate of D-Inositol-1,4,5-triphosphate synthesis without doing any optical resolution by utilizing C2 symmetry.
Diastereoselective Claisen Condensation-Type Reactions of Alkyl 2,2-Dialkoxycyclopropanecarboxylates with Esters and Acid Chlorides Promoted by Titanium(IV) Chloride
Authors: Shimada Shigeru , Saigo Kazuhiko , Hashimoto Yukihiko , Maekawa Yasunari , Yamashita Takashi , Yamamoto Taketsugu , Hasegawa Masaki
Published: May 2006

In the presence of titanium(IV) chloride, alkyl 2,2-dialkoxycyclopropane carboxylates reacted with esters and acid chlorides to give Claisen condensation-type products. The reaction essentially proceeded with extremely high diastereoselectivity.
Reaction of Tantalum–Alkyne Complexes with Isocyanates Leading to (E)-α,β-Unsaturated Amides. Stereoselective Functionalization of Carbon-Carbon Triple Bonds
Authors: Takai Kazuhiko , Kataoka Yasutaka , Yoshizumi Kazuyuki , Oguchi Yoshiyuki , Utimoto Kiitiro
Published: May 2006

Treatment of alkynes with low-valent tantalum derived from TaCl5 and zinc produces tantalum-alkyne complexes (not isolated), which react with phenylisocyanate (or butylisocyanate) to give (E)-α,β-unsaturated amides stereoselectively.
Preparation of Iron(III) Complex with Nitrilotriacetic Acid and Origin of Its Unique Reactivity
Authors: Nishida Yuzo , Yoshizawa Kaori , Akamatsu Tetsuya
Published: May 2006

We have succeeded in isolating the iron(III) complex with nitrilotriacetate(nta3−) and concluded that this complex exists as μ-oxo dimeric species in both the solid and solution states. The unique reactivity observed for this complex solution was discussed in relation to its dimeric structure.
On the Mechanism of Oligomerization of Propylene by (C5Me5)2MCl2/Methylalumoxane Catalysts (M = Zr, Hf)
Authors: Mise Takaya , Kageyama Akiko , Miya Shinya , Yamazaki Hiroshi
Published: May 2006

In the oligomerization of propylene by (C5Me5)2MCl2 (M = Zr,Hf)/methylalumoxane, formation of abnormal oligomers such as 1-pentene(C5), 2,4-dimethyl-1-pentene(C7), 4-methyl-1-heptene(C8), and 2,4,6-trimethyl-1-heptene(C10) besides normal oligomers such as 4-methyl-1-pentene(C6) and 4,6-dimethyl-1-heptene(C9) is indicative of the mixing of unusual β-CH3 and usual β-H transfer terminations from each growing carbon chain which was initiated by insertion of propylene into either M–H or M–Me bond.
Adsorption of Metal Ions on a New Chelating Ion-Exchange Resin Chemically Derived from Chitosan
Authors: Tong Philip , Baba Yoshinari , Adachi Yoshio , Kawazu Kazuyoshi
Published: May 2006

A new chelating ion-exchange resin, pyrididene-chitosan, was synthesized through the reaction of pyridine-2-aldehyde with the free amino groups of chitosan. The pH dependencies and adsorption isotherms in the adsorption of various metal ions on the resin were investigated from 1 mol/1 of aqueous ammonium nitrate solution.
Photoreaction of 2,3-Bis[2-(4-chlorophenyl)ethenyl]pyrazine in the Crystalline State and in Acetonitrile Solution
Authors: Tsutsumi Takehiro , Takeuchi Atsuo , Hashimoto Yukihiko , Hasegawa Masaki , Iitaka Yoichi
Published: May 2006

The photoreaction behaviors of 2,3-bis[2-(4-chlorophenyl)ethenyl]pyrazine (1) in the crystalline state as well as in acetonitrile solution were examined mechanistically. In the crystalline state, stepwise [2+2] cycloadditions occurred between two facing molecules under the crystal lattice control to give a [2.2]orthocyclophane derivative in 74% yield. Photoirradiations of 1 in acetonitrile solution were also performed. In this case, products distributions were changed depending on the cut off wavelength.
Reactions of syn- and anti-Benzylideneaniline Radical Anions
Authors: Ishida Akito , Itoh Hiroshi , Takamuku Setsuo
Published: May 2006

Reactions of a benzylideneaniline radical anion have been studied by spectral and product analyses, in which successive irradiation of uv-light and ionizing radiation at low temperature have been applied to the production of the unstable syn-radical anions.
A New Amino Acid, L-3-(2-Carboxy-4-pyirolyl)-alanine from the Poisonous Mushroom Clytocybe acromelalga
Authors: Yamano Kimiaki , Konno Katsuhiro , Shirahama Haruhisa
Published: May 2006

A new amino acid, L-3-(2-carboxy-4-pyrrolyl)-alanine was isolated from Clytocybe acromelalga. Its structure was determined by spectral data and a synthesis.
An Optically Active Cobalt(III) Complex Containing Co–C Bond Prepared by the Photolysis of Optically Active (Ethylenediamine)(ethyleriediamirie-N,N′-dipropionato)cobalt(III) Complex Ion
Authors: Ama Tomoharu , Hasegawa Nobuyoshi , Kawaguchi Hiroshi , Yasui Takaji
Published: May 2006

An optically active cobalt(III) complex ion containing Co–C bond, (H2eedmp: 4,7-diaza-nonanoicacid; en: ethylenediamine), was prepared by the photolysis of (H2eddp: ethylenediamine-N,N′-dipropionic acid). This complex was stable and hardly racemized in an aqueous solution. A 13C NMR signal broadened by the Co–C spin-spin coupling was observed at −5.5 ppm.
Olefin Oxidation Catalyzed by Electron Deficient Metallo-Porphyrin
Authors: Ogoshi Hisanobu , Suzuki Yasuhiko , Kuroda Yasuhisa
Published: May 2006

Olefin oxidations catalyzed by Fe or Mn complexes of 2,4,6,8-tetratrifluoromethyl-1,3,5,7-tetraethylporphyrin (TFTEP) using iodosobenzene as oxidant were investigated. Comparison of TFTEP with usual OEP/iodosobenzene systems shows that the electronic effect in porphyrin ring does not seriously affect the selectivity of norbornene oxidations.
Conglomeratic Solid Solutions in trans(N,t-N)-[Co(leucinato)(tren)]I2 and trans(N,t-N)-[Co(norleucinato)(tren)](ClO4)2 (tren = tris(2-aminoethyl)amine)
Authors: Yamanari Kazuaki , Fuyuhiro Akira
Published: May 2006

Ternary solubility isotherms of trans(N,t-N)-[Co(leu)(tren)]I2 and trans(N,t-N)-[Co(n-leu)(tren)](ClO4)2 (leu = leucinate(1−), n-leu = norleucinate(1−), and tren = tris(2-aminoethyl)amine) at 25 °C consist of two branches of solubility curve and one eutectic point, but the tie lines do not converge to any apex of the pure enantiomers and diverge widely. These facts mean that both racemates form a conglomerate and simultaneously a solid solution. The X-ray crystal analysis of the former iodide (D : L = 63 : 37; space group P32) confirms the existence of this conglomeratic solid solution.
Reversal of Diastereofacial Selectivity in the Addition Reaction of Organometallics to Chiral Imines
Authors: Ukaji Yutaka , Watai Toshiyuki , Sumi Takashi , Fujisawa Tamotsu
Published: May 2006

It was observed that diastereofacial selectivity in the addition reaction of organometallics to the chiral imines derived from (R)-2-methoxy-1-phenylethylamine was regulated under appropriate conditions; i. e., organolithium and organocerium reagents added from the re-face of the chiral imines selectively, while organocopper reagents attacked from the si-face. The utility of the present method was demonstrated in the enantioselective synthesis of solenopsin A.
Synthesis of the Functionalized Cyclohexanecarbaldehyde Derivative. A Potential Key Compound for Total Synthesis of Optically Active Tetrodotoxin
Authors: Sato Ken-ichi , Kajihara Yasuhiro , Nakamura Yutaka , Yoshimura Juji
Published: May 2006

Oxidation of 1L-(1,2,3′,4,5/3,6)-3-hydroxymethyl-2,4,5-tri-O-methoxymethyl-3,3′-O-methylene-6-nitro-2,3,4,5-tetrahydroxycyclohexanecarbaldehyde dimethyl acetal with potassium t-butoxide and m-chloroperbenzoic acid has given corresponding carbonyl derivative in 65% yield. The carbonyl compound has been successfully converted into the desired key compound for tetrodotoxin synthesis in excellent yield via the spiro α-chloro-epoxide derivative.
Selective Dyeing of Organopolysilane Films Patterned by Ultra-violet Light Irradiation
Authors: Yokoyama Masaaki , Koura Takashi , Hiroshige Yuji , Notsu Shusuke
Published: May 2006

Utilizing the swelling effect induced by UV light irradiation in organopolysilane films, the patterned dyeing with water-soluble dyes was successfully demonstrated. Only basic dyes gave the dyeing effect, suggesting the existence of a specific interaction between basic dyes and Si–OH moieties formed by UV photodecomposition. The narrow line pattern of 40 μm width was completely reproduced with dyeing.
DC Conductivity of Li1.3Al0.3Ti1.7(P4)3 Ceramic with Li Electrodes
Authors: Aono Hiromichi , Sugimoto Eisuke , Sadaoka Yoshihiko , Imanaka Nobuhito , Adachi Gin-ya
Published: May 2006

The ionic conductivity of a solid electrolyte, Li1.3Al0.3Ti1.7(PO4)3, was measured with Li and Li–Al alloy electrodes. The contact resistance between the Li electrode and the electrolyte was a dominant factor for the DC conductivity. A higher DC conductivity was obtained by an utilization of the Li4Al alloy electrodes.
Peak Splitting for Co(III) and Al(III) Complexes in High Performance Liquid Chromatography by Linkage Isomerism of Unsymmetric o,o′-Dihydroxyazobenzene Derivatives
Authors: Wada Hiroko , Hakamata Takeshi , Yasui Katsuro , Yuchi Akio , Nakagawa Genkichi
Published: May 2006

Peak splitting, which was found in reversed phase chromatography of Co(III) and Al(III) complexes with unsymmetric dihydroxyazobenzene derivatives, is ascribed to linkage isomerism by 1H NMR spectroscopy. Both isomerization and dissociation reactions take place in the column in contrast to normal phase chromatography.
Separation of Enantiomeric Amino Acid Derivatives on Axially Chiral 1,1′-Binaphthyl-2,2′-bis(N-decylcarboxamide) as a Stationary Phase for Capillary Gas Chromatography
Authors: Ôi Shuichi , Ochiai Yoshiro , Miyano Sotaro
Published: May 2006

Axially chiral 1,1′-binaphthyl-2,2′-bis(N-decylcarboxamide) was utilized as a chiral stationary phase for capillary gas chromatograpic separation of enantiomers. This stationary phase showed efficient differentiation for amino acid derivatives allowing complete separation of eleven N-trifluoroacetyl amino acid isopropyl esters.
Simple Synthesis and the Diels–Alder Reaction of 3-(p-Tolylthio)-2-(trimethylsilyloxy)-1,3-butadiene
Authors: Kosugi Hiroshi , Hoshino Kunihide , Uda Hisashi
Published: May 2006

The reaction of 3-(p-tolylsulfinyl)-2-butanone with trimethylsilyl trifluoromethanesulfonate in the presence of diisopropylethylamine gave 3-(p-tolylthio)-2-(trimethylsilyloxy)-1,3-butadiene (2) quantitatively. The Diels–Alder reactions of 2 and the related dienes with methyl acrylate were studied.
Catalytic Hydrogenation of Alkenes Using Zirconocene–Alkene Complexes
Authors: Takahashi Tamotsu , Suzuki Noriyuki , Kageyama Motohiro , Nitto Yu , Sabur Masahiko , Negishi Ei-ichi
Published: May 2006

Hydrogenation reactions of alkenes were catalyzed by zirconium–alkene complex derivatives which were prepared from Cp2ZrCl2 (Cp = η5-C5H5) and n equiv. of RR′CHCH2M (M = MgX or Li). By the use of three or more equiv. of EtMgBr relative to Cp2ZrCl2, the product yield of hydrogenation of 1-decene was remarkably improved most likely due to the stabilization of the Zr(II) species.
Implications of the Positive Band at 1712 cm−1 in the Light-Induced Infrared Difference Spectrum of the Bacteriochlorophyll-a Special Pair in the Photosynthetic Reaction Center of Chromatium vinosum
Authors: Morita Eugene Hayato , Hayashi Hidenori , Tasumi Mitsuo
Published: May 2006

Assignments of bands observed in the light-induced infrared difference spectrum of reaction centers from Chromatium vinosum are discussed with particular attention to the carbonyl stretching region of the bacteriochlorophyll-a (BChl) special pair radical cation. It is pointed out that the infrared data reflect the localization of an unpaired electron on either one of the two bacteriochlorophyll-a’s in the special pair radical cation in the time scale of infrared absorption (10−13s).
Relationship between the Alignment of Liquid Crystal and Macroscopic Properties of Pyrolyzed Polyimide Langmuir–Blodgett Films
Authors: Akatsuka Takahisa , Tanaka Hideaki , Toyama Jiro , Nakamura Takayoshi , Matsumoto Mutsuyoshi , Kawabata Yasujiro
Published: May 2006

The aligning properties of liquid crystal on pyrolyzed polyimide Langmuir–Blodgett (PPI LB) films were studied together with the conductivity and the morphology of PPILB films. The aligning direction of the liquid-crystal was parallel to the dipping direction of the LB films.
Oxidation of Cytosine and 5-Methylcytosine Nucleosides and 5-Methyl-2′-deoxycytidine 5′-Monophosphate with Peroxosulfate Ions
Authors: Itahara Toshio
Published: May 2006

Reaction of 5-methylcytosine nucleosides and nucleotide with Na2S2O8 resulted in an oxidation of the 5-methyl group, while treatment of them and cytosine nucleosides with KHSO5 gave the corresponding N3-oxides.
Molecular Recognition by a Cationic Cage-type Host Bearing Chiral Binding Sites
Authors: Murakami Yukito , Ohno Teruhisa , Hayashida Osamu , Hisaeda Yoshio
Published: May 2006

The guest-binding behavior of a novel cage-type host bearing chiral binding sites was examined in aqueous media. The binding constants for inclusion of non-ionic and anionic dyes were in the order of 105–106 mol−1 dm3, and the circular dichroism was induced on an incorporated achiral guest through its stereochemical interaction with the chiral host cavity.
Facile Access to 2-Alkylidene 3-Oxy Propanals and Propionic Acids from Conjugated Enals
Authors: Huot Jean-Frangois , Outurquin Francis , Paulmier Claude
Published: May 2006

Conjugated enals or their methyl acetals react with benzeneselenenyl chloride in the presence of an oxygen nucleophile to give Michael-type adducts. The latter are oxidized into 2-alkylidene 3-oxy propanals and propionic acids.
Chemoenzymatic Synthesis of Both Enantiomers of Fluoxetine
Authors: Chenevert Robert , Fortier Geneviéve
Published: May 2006

Both enantiomers of fluoxetine have been synthesized from ethyl benzoylacetate. The key step is the enantioselective reduction of the starting material by baker’s yeast.
Separation, Detection, and UV/Visible Absorption Spectra of Fullerenes; C76, C78, and C84
Authors: Kikuchi Koichi , Nakahara Nobuo , Honda Masahiro , Suzuki Shinzo , Saito Kazuya , Shiromaru Haruo , Yamauchi Kotaro , Ikemoto Isao , Kuramochi Tadao , Hino Shojun , Achiba Yohji
Published: May 2006

New kinds of fullerenes were separated by HPLC with benzene from carbon soot. At least four fractions were well separated. Mass analysis confirmed the separation of C60, C70, C84 and the mixture of C76 and C78. Absorption spectra of C76, C78, and C84 were measured for the first time.
Tungsten Oxide-Based Semiconductor Sensor Highly Sensitive to NO and NO2
Authors: Akiyama Morito , Tamaki Jun , Miura Norio , Yamazoe Noboru
Published: May 2006

A sintered sensor element based on WO3 was found to be very sensitive to NO and NO2. The sensitivity, defined as the ratio of the resistance in the gases to that in air, was as high as 31 and 97 to 200 ppm NO and 80 ppm NO2, respectively, at 300 °C. The element was well suited for sensing the gases at low levels. Satisfactory performances to NO and NO2 were exhibited in the regions of 0–800 ppm and 0–200 ppm, respectively.
Synthesis of E-Vinylsilanes from Olefins with Vicinal Silyl and Stannyl Substituents
Authors: Mori Miwako , Watanabe Naoshi , Kaneta Naotake , Shibasaki Masakatsu
Published: May 2006

E-Vinylsilanes were synthesized regioselectively from olefins with vicinal silyl and stannyl substituents, prepared from the corresponding terminal alkynes, by destannylation with HI.
Triethylaluminum Catalyzed Ring Opening Reaction of 1-Acetyl-2-[(trimethylsilyl)methyl]cyclobutanes. Stereoselective Preparation of (Z)-Enol Trimethylsilyl Ethers
Authors: Fujiwara Tooru , Suda Atsushi , Takeda Takeshi
Published: May 2006

The triethylaluminum catalyzed ring opening reaction of 1-acetyl-2-[(trimethylsilyl)methyl]cyclobutanes gave (Z)-6-(trimethylsiloxy)-1,5-heptadienes stereoselectively. The starting materials were easily prepared by the 1,4-addition of (trimethylsilyl)methylmagnesium chloride to 1-cyclobutenyl ketones.
Synthesis and Properties of Optically Active 3-Aryl-5-alkyloxazolidin-2-ones. New Chiral Dopants for Ferroelectric Liquid Crystals
Authors: Kusumoto Tetsuo , Sato Ken-ichi , Hiyama Tamejiro , Takehara Sadao , Osawa Masashi , Nakamura Kayoko , Fujisawa Toru
Published: May 2006

New chiral dopants for ferroelectric liquid crystals containing an optically active oxazolidin-2-one moiety, synthesized from (R)-1,2-epoxyoctane, exhibit large spontaneous polarization.
Structure of Aerugidiol, a New Bridge-head Oxygenated Guaiane Sesquiterpene
Authors: Masuda Toshiya , Jitoe Akiko , Nakatani Nobuji
Published: May 2006

The structure elucidation of aerugidiol, a new bridge-head oxygenated sesquiterpene isolated from the rhizomes of Curcuma aeruginosa, is described.
C-2 Epimerization of Disaccharides by Calcium(II)–Monoamine Systems. A Direct Synthesis of (1→4)-Linked Disaccharides Having a D-Mannose Unit as a Reducing Terminal
Authors: Takei Tomoyuki , Tanase Tomoaki , Yano Shigenobu , Hidai Masanobu
Published: May 2006

(1→4)- and (1→6)-linked disaccharides were epimerized at C-2 of the reducing terminal under mild conditions by calcium(II)–N-alkylated monoamine systems. Naturally rare (1→4)-linked heterodisaccharides having a D-mannose unit as a reducing terminal can be prepared in one step from disaccharides having a D-glucose unit which are abundunt in nature.
Chemical Oxidation of Polyaniline by Radical Generating Reagents, O2, H2O2–FeCl3 Catalyst, and Dibenzoyl Peroxide
Authors: Moon Doo-Kyung , Maruyama Tsukasa , Osakada Kohtaro , Yamamoto Takakazu
Published: May 2006

Polyaniline in the reduced form , leucoemeraldine base form) undergoes oxidation by radical generating reagents such as O2, H2O2–FeCl3, catalyst system, and dibenzoyl peroxide to give the 50% oxidized polymer , emeraldine base form). The oxidation by the H2O2–FeCl3 system shows kinetic behaviors characteristic of Fenton-type oxidation.
Photoinduced Electron and Hydrogen-Transfer Reaction in Micellar-Promoted Reduction of vic-Styrene Dibromide with 1-Benzyl-1,4-dihydronicotinamide
Authors: Yamashita Kohichi , Ishida Hitoshi , Ohkubo Katsutoshi
Published: May 2006

The photoreduction of vic-styrene dibromide by 1-benzyl-1,4-dihydronicotinamide (BNAH) gave (1-bromoethyl)benzene (StyHBr) in addition to styrene (Sty); Among the both products, StyHBr formation was found to include a direct hydrogen migration from BNAH by isotopic experiments with [2H2]BNAH. The remarkable acceleration of such a characteristic photoreaction became possible by the presence of ionic micelles.
Aggregation Structure of Bacteriochlorophyll c in Chlorosomes from Chlorobium tepidum
Authors: Nozawa Tsunenori , Suzuki Manabu , Ohtomo Katsunori , Morishita Yumi , Konami Hideo , Madigan Michael T
Published: May 2006

High resolution solid state 13C NMR signals of bacteriochlorophyll (BChl) c were obtained for chlorosomes from Chlorobium tepidum. Observed BChl c signals which resembled those from oligomeric BChl c afforded ring current shift from which an aggregation structure was proposed.
Photoelectrochemical Behavior of Purple Membrane Langmuir–Blodgett Films at the Electrode–Electrolyte Interface
Authors: Miyasaka Tsutomu , Koyama Koichi
Published: May 2006

Langmuir–Blodgett films of the halobacterial purple membrane were formed on SnO2 conductive electrodes. Generation and the behavior of bacteriorhodopsin induced photocurrents at the interface of electrode and aqueous electrolyte were investigated under controlled potentials in an electrochemical cell. Efficient and rectified photocurrents were obtained, demonstrating significant dependence on the electrode potential and pH of the electrolyte.
Transannular Se–Se Interaction in Electrochemical Oxidation of 5H,7H-Dibenzo[b,g][1,5]diselenocin and Formation of Its Diselena Dication in Concentrated Sulfuric Acid
Authors: Fujihara Hisashi , Ueno Yoko , Chiu Jer-Jye , Furukawa Naomichi
Published: May 2006

5H,7H-Dibenzo[b,g][1,5]diselenocin (1) undergoes the reversible electrochemical oxidation with low oxidation potential which is attributed to the transannular Se–Se interaction. The formation of diselena dication of 1 was observed in the reaction of 1 and its Se-oxide with concd H2SO4 by 1H, 13C, and 77Se NMR spectroscopy.
Lipase-Catalyzed Resolution of 2-Substituted 3-Cyclopenten-1-ol Derivatives
Authors: Sakai Takashi , Iida Yasuhiro , Kikuyama Shigeki , Tsuboi Sadao , Utaka Masanori
Published: May 2006

2-Oxabicyclo[3.3.0]oct-6-en-3-one, the key intermediate in the prostaglandin synthsis, was subjected to the optical resolution effectively by use of lipase after conversion to 2-[2-(t-butyldimetylsilyloxy)ethyl]-3-cyclopenten-1-yl acetate and 2-[2-(N,N-dimethylcarbamoyl)methyl]-3-cylopenten-1-yl acetate.
The Catalytic Beckmann Rearrangement of Ketoxime Trimethylsilyl Ethers Using an Antimony(V) Salt
Authors: Mukaiyama Teruaki , Harada Tsunehiro
Published: May 2006

In the presence of a catalytic amount of an antimony(V) salt generated from antimony(V) chloride and silver antimonate, the Beckmann rearrangement of several ketoxime trimethylsilyl ethers proceeds smoothly to give the corresponding amides or lactams in good yields.
Specific Cage Effects Provided by Kyuphane on Guest Recognition in Aqueous Media
Authors: Murakami Yukito , Kikuchi Jun-ichi , Ohno Teruhisa , Hirayama Takayuki , Hisaeda Yoshio , Nishimura Hiroshi
Published: May 2006

The fluorescence of α-PNA placed in Kyuphane was quenched by ketones incorporated into the same host cavity. A metastable 1:2 Kyuphane-pyrene complex initially formed was transformed into a thermodynamically stable 1:1 species as confirmed by fluorescence spectroscopy with attention to the monomer and excimer emission originated from pyrene.
Selective Dimerization by Paired Electrolysis of Enol Acetate
Authors: Maekawa Hirofumi , Nakano Kazuharu , Hirashima Tsuneaki , Nishiguchi Ikuzo
Published: May 2006

Electrolysis of enol esters of cyclic ketones possessing an alkyl group at the α-position using graphite carbon electrodes (EGM62 or EG10 : Nippon Carbon Co. Ltd.) brought about selective dimerization at the β-position of the ketones to give the corresponding 1,6-diketones in good to moderate yields. It was found that initial anodic formation of α,β-unsaturated ketones was successively followed by cathodic hydrodimerization (paired electrolysis) in an undivided cell.
Trichlorolanthanoid (LnCl3)/Zn Catalyzed Cyclodimerization of Chalcone
Authors: Takaki Ken , Nagase Kyoko , Beppu Fumikazu , Fujiwara Yuzo
Published: May 2006

The trichlorolanthanoid (LnCl3)/Zn system has been found to cause cyclodimerization of chalcone to give cyclopentanol derivatives (1 and 2) in both high yields and selectivities (1/2 ratio) compared with the reaction by Yb metal alone. Of trichlorolanthanoids the chlorides of Yb and Eu or Sm showed maximum yields and selectivities (1/2).