bluuebunny/crossref_metadata_2025_split huggingface dataset:
TRANSANNULAR CYCLIZATION OF [1(10)E,4Z]-3β,8β-DIHYDROXY-13-METHOXY-1(10),4-GERMACRADIENO-12,6α-LACTONE. FORMATION OF CADINANE-TYPE LACTONES
Authors: Toma Kazunori , Murae Tatsushi , Takahashi Takeyoshi 
Published: July 2006

Abstract
On treatment with boron trifluoride etherate, [1(10)E,4Z]-3β,8β-dihydroxy-13-methoxy-1(10),4-germacradieno-12,6α-lactone (1) gave five cadinane-type 12,8β-lactones by transannular cyclization and concomitant lactonization with the C-8 hydroxyl group. Some of the cadinane-type lactones were also formed by thermal reaction of 1.
SYNTHESIS OF C-TERMINAL HEPTAPEPTIDE ANALOGS OF SUBSTANCE P: THE SUBSTITUTION OF GLUTAMINE BY GLYCINE OR 5-AMINOVALERIC ACID
Authors: Torigoe Keisuke , Katayama Takayoshi , Sofuku Shosuke , Muramatsu Ichiro 
Published: July 2006

Abstract
C-Terminal heptapeptide analogs of substance P, in which the glutaminyl residues were substituted by Gly or δAva, were synthesized by the liquid phase method. These analogs showed substance P activity. The results suggest that glutaminyl residues are not essential for the intrinsic activity on a guinea-pig ileum.
STEREOSELECTIVE SYNTHESIS OF (±)-INTEGERRINECIC ACID
Authors: Narasaka Koichi , Uchimaru Tadafumi 
Published: July 2006

Abstract
A synthesis of (±)-integerrinecic acid, an acid part of 12-membered bislactonic pyrrolizidine alkaloid, has been achieved stereoselectively starting from 2-methyl-2-cyclopentenone.
CATALYTIC ELECTROREDUCTION OF MOLECULAR OXYGEN AT GLASSY CARBON ELECTRODES MODIFIED WITH IRON PORPHYRINS
Authors: Kobayashi Nagao , Fujihira Masamichi , Osa Tetsuo , Dong Shaojun 
Published: July 2006

Abstract
The reduction of molecular oxygen (O2) at glassy carbon surfaces modified with iron porphyrins was studied by cyclic voltammetry and differential pulse polarography in 0.05 mol dm−3 aqueous H2SO4 solution. O2 was reduced more effectively at the electrode modified with iron porphyrin lying in parallel to the electrode surface than at the one with iron porphyrin protruding vertically from the surface.
SYNTHESIS OF VICINALLY SUBSTITUTED CYCLOPENTENE DERIVATIVE VIA CYCLOADDITION OF METHYL(PHENYL(OR TERT-BUTYL)THIOMETHYL)KETENE
Authors: Ohshiro Yoshiki , Ishida Masaru , Shibata Jun-ichi , Minami Toru , Agawa Toshio 
Published: July 2006

Abstract
Cycloaddition of methyl(phenyl(or tert-butyl)thiomethyl)ketene to cyclopentadiene gave a bicyclic cyclobutanone derivative which was further transformed to cyclopentene systems having alkenyl and carbonyl substituents at vicinal positions.
CHARACTERISTIC BEHAVIOR OF N-(PHENYLSULFONYL)BENZOHYDRAZONOYL AZIDE. BASE-INDUCED DECOMPOSITION TO BENZONITRILE AND CYCLIZATION TO A TETRAZOLE
Authors: Ito Suketaka , Tanaka Yumo , Kakehi Akikazu 
Published: July 2006

Abstract
N-(Phenylsulfonyl)benzohydrazonoyl azide decomposed to give benzonitrile on treatment with triethylamine at room temperature, and cyclized to 5-pnenyl-1-(phenylsulfonyl)aminotetrazole on heating in benzene, along with the formation of benzonitrile and other products.
1,4-ADDITION REACTION OF NON-ALLYLIC SULFONYL CARBANION WITH CYCLOPENTENONE DERIVATIVE IN THE PRESENCE OF HMPA. SYNTHESIS OF 15-KETO PROSTAGLANDIN F1
Authors: Nokami Junzo , Ono Toshio , Kurihara Hideyuki , WaKabayashi Shoji 
Published: July 2006

Abstract
1,4-Addition reaction of aliphatic (non-allylic) sulfonyl carbanion to cyclopentenone derivative was studied to build the vinyl ketone function at the β position of the carbonyl of cyclopentenone. 15-Keto PG F1 (6) was synthesized from sulfone ketal 1 and cyclopentenone derivative 2.
OXYGEN EVOLUTION BY WATER OXIDATION WITH TRIS(2,2′-BIPYRIDYL)RUTHENIUM(III) COMPLEX
Authors: Kaneko Masao , Awaya Nobuhiko , Yamada Akira 
Published: July 2006

Abstract
Oxygen evolution by water oxidation with tris(2,2′-bipyridyl)ruthenium(III) complex was studied by mass spectrum, gas chromatography, visible spectrum, and volumetric method. It was confirmed that water is oxidized to give dioxygen. A model for water oxidation through Ru(bpy)32+ was studied.
AN ENANTIOSELECTIVE ROUTE TO AN INTERMEDIATE OF THE CARBAPENAM SYSTEM FROM THE CHIRAL γ-BUTYROLACTONE
Authors: Takano Seiichi , Kasahara Chiyoshi , Ogasawara Kunio 
Published: July 2006

Abstract
A new enantioselective synthesis of the keto ester(16) containing β-lactam ring system has been developed using the chiral lactone(1) as a starting material.
USE OF UNCHARGED NEUTRAL LIGANDS IN THE ISOTACHOPHORETIC ANALYSIS OF ALKALI AND ALKALINE EARTH METALS
Authors: Tazaki Masato , Takagi Makoto , Ueno Keihei 
Published: July 2006

Abstract
The use of uncharged complexing agent in the isotachophoretic separation of ions is described. 18-Crown-6 interacted with ammonium and some alkali and alkaline earth metal ions, improving the separation among these ions. α-Cyclodextrin assisted the separation of anions through a host–guest interaction.
A CONVENIENT METHOD FOR THE PREPARATION OF N,N′-DISUBSTITUTED THIOUREAS USING 2-CHLOROPYRIDINIUM SALT, SODIUM TRITHIOCARBONATE AND AMINES
Authors: Takikawa Yuji , Inoue Noriyuki , Sato Ryu , Takizawa Saburo 
Published: July 2006

Abstract
N,N′-Disubstituted thioureas were prepared in high yields by treating 2-chloropyridinium salt with sodium trithiocarbonate and subsequently adding amines.
HYDROXYLATION OF BENZENE BY HYDROGEN PEROXIDE CATALYZED BY AN Fe3+-CATECHOL CATALYST SUPPORTED ON SILICA GEL
Authors: Tamagaki Seizo , Hotta Kazuhiko , Tagaki Waichiro 
Published: July 2006

Abstract
A silica gel-supported Fe3+-catechol catalyst was found to be active to convert benzene to phenol in moderate yields.
ALKALINE HYDROLYSIS OF A p-NITROPHENYL ESTER CATALYZED BY PROTEIN–SURFACTANT COMPLEXES
Authors: Koga Joichi , Chen Keng-Ming , Nawata Masahiro , Yamazaki Yoshihiro , Kuroki Nobuhiko 
Published: July 2006

Abstract
The large enhancement in the rate of alkaline hydrolysis of p-nitrophenyl hexanoate in aqueous solutions of tetradecyltrimethylammonium bromide in the presence of bovine serum albumin was found. A maximum in the rate enhancement appeared in the vicinity of the critical micelle concentration of the surfactant. It was suggested that the rate enhancement was attributable to the formation of protein–surfactant complexes providing a new pseudo-phase for the reaction.
A NOVEL STEREOCHEMICAL ASPECT OF NITRO SUGAR DERIVATIVES: “AXIAL” NITRO GROUP PREDOMINATED OVER EQUATORIAL ONE IN EQUILIBRIUM
Authors: Sakakibara Tohru , Minami Toshiaki , Ishido Yoshiharu , Sudoh Rokuro 
Published: July 2006

Abstract
2-Nitro sugar derivatives bearing an axial nitro group were proved to be thermodynamically more stable than the corresponding 2-epimers, bearing an equatorial nitro group.
SELECTIVE CATALYTIC HYDROGENATION OF PROPARGYL ALCOHOL WITH HETEROPOLY ACID-MODIFIED PALLADIUM
Authors: Izumi Yusuke , Tanaka Yoshiyuki , Urabe Kazuo 
Published: July 2006

Abstract
The Keggin type heteropoly acid was readily reduced with hydrogen in the aqueous phase at 30°C in the presence of Pd(II) or metallic Pd, taking up 1 to 11 molecules of hydrogen per Keggin unit. The palladium catalyst prepared by the H2-reduction of an aqueous solution containing Pd(II) and heteropoly acid was very effective for the aqueous-phase selective semihydrogenation of propargyl alcohol.
AN ION-FLOTATION METHOD FOR EVALUATING THE INTERACTION OF ZINC ION WITH HUMIC ACID
Authors: Sugawara Masao , Saito Shigeru , Kambara Tomihito 
Published: July 2006

Abstract
An ion-flotation technique by using a surface-active cetylpyridinium chloride (CPC) in conjunction with spectrophotometry was found to be a useful method for evaluating the degree of interaction of zinc(II) with soil-derived humic acid.
THE CONDENSATION OF p-TROPOQUINONES WITH 5-HYDROXYTROPOLONE: A “PHENOL OXIDATION REACTION” IN THE TROPONOID SYSTEM
Authors: Takeshita Hitoshi , Kusaba Tomoyuki , Mori Akira 
Published: July 2006

Abstract
Condensation of p-tropoquinones and 5-hydroxytropolones, preferably by acid, yielded dicycloheptafurandione derivatives, which have the same carbon framework with utahin, a naturally-occurring dimeric tropolone. Partial oxidation of 5-hydroxytropolones and partial reduction of p-tropoquinones respectively yielded the condensates. This should exemplify the “phenol oxidation” in troponoids.
REGIOSELECTIVITY OF β-VINYL-β-PROPIOLACTONE TOWARD VARIOUS NUCLEOPHILES
Authors: Fujisawa Tamotsu , Sato Toshio , Takeuchi Masashi 
Published: July 2006

Abstract
Regioselectivity in the reaction of β-vinyl-β-propiolactone with various nucleophiles was found to depend on the hard and soft acid and base (HSAB) principle. A hard base such as methoxide ion attacked the acyl carbon exclusively, while the nucleophilic attack of soft bases such as iodide and dialkyl cuprate preferred the terminal vinyl carbon to the β-carbon.
CATALYTIC ACTIVITIES OF ALKALINE EARTH METAL OXIDES FOR DISPROPORTIONATION OF NITROGEN MONOXIDE
Authors: Kanno Yoshinori , Imai Hisao 
Published: July 2006

Abstract
The disproportionation of nitrogen monoxide over alkaline earth metal oxides was carried out at 0°C. The catalysts were found to exhibit high activity for the formation of dinitrogen oxide from nitrogen monoxide. The order of the catalytic activity per unit surface area was obtained as MgO&gt; CaO&gt; SrO&gt; BaO.
HYDRIDING BEHAVIORS OF ZrxTi1−x(FeyMn1−y)z ALLOYS
Authors: Suzuki Akira , Nishimiya Nobuyuki , Ono Shuichiro , Higano Sakae , Kamino Kimiyuki 
Published: July 2006

Abstract
ZrxTi1−x(Fey Mn1−y)z alloys, where x and y are 0 to 1 and z is 1 to 2, are found to have practically promising characteristics that their hydrogen equilibrium pressures can be adjusted to 0.1 to 1 MPa at about 400K by varying the three parameters.
ABSORPTION OF DIHYDROGEN BY [Fe4S4(SPh)4]2− AND [Mo2Fe6S8(SPh)9]3−, AND THE H–D EXCHANGE REACTION BETWEEN H2 AND D2 CATALYZED BY THE REDUCED SPECIES OF THESE CLUSTERS
Authors: Tanaka Masahiro , Tanaka Koji , Tanaka Toshio 
Published: July 2006

Abstract
Two and four molar amounts of H2 can be absorbed quantitatively by [Fe4S4(SPh)4]2− and [Mo2Fe6S8(SPh)9]3−, respectively, in dimethylformamide, and the H2-absorbed clusters exhibit the metal-hydride stretching bands in the matrix of polyvinylchloride films. Moreover, the reduced species of the clusters prepared chemically or electrochemical ly catalyze the H–D exchange reaction between H2 and D2. The active species for the catalytic reaction are shown to be [Fe4S4(SPh)4]4− and [Mo2Fe6S8(SPh)9]5−.
RING OPENING OF CYCLOPROPYL KETONES ASSISTED BY THE TRIMETHYLSILYL GROUP
Authors: Ochiai Masahito , Sumi Kenzo , Fujita Eiichi 
Published: July 2006

Abstract
Cyclopropyl ketones 2 were smoothly cleaved with boron trifluoride-acetic acid under mild reaction conditions by the assistance of trimethylsilyl group to give γ,δ-enones in good yields and the reaction was applied to the formal total synthesis of cis-jasmone.
PREPARATION OF NEW PHTHALOCYANINE COMPLEXES OF SOME RARE-EARTH ELEMENTS
Authors: Sugimoto Hiroshi , Higashi Teruaki , Mori Masayasu 
Published: July 2006

Abstract
The reaction of tris(1,3-diphenyl-1,3-propanedionato) complexes of heavier rare-earth elements, M3+(dbm)3 and lithium phthalocyaninato(2−), Li2(pc) gave two types of new stable phthalocyanine complexes, [M3+(pc) (dbm) (dbmH)] and [M3+(pc) (dbm)] depending on the solvents used for the preparation. The structure of both types of complexes are tentatively proposed.
NOVEL CONVERSION OF A KETONE DIMETHYL DITHIOACETAL S,S-DIOXIDE TO THE CORRESPONDING KETONE AND ITS APPLICATION TO SYNTHESIS OF ACYCLIC AND CYCLIC KETONES
Authors: Ogura Katsuyuki , Suzuki Michiyo , Watanabe Jun-ichi , Yamashita Mitsuo , Iida Hirotada , Tsuchihashi Gen-ichi 
Published: July 2006

Abstract
A ketone dimethyl dithioacetal S,S-dioxide was easily hydrolyzed with hydrochloric acid in refluxing methanol and this transformation was applied to a new method for making acyclic and cyclic ketones by the use of formaldehyde dimethyl dithioacetal S,S-dioxide.
DIMERIZATION OF ALKYL VINYL KETONES WITH SODIUM NITRITE-ACETIC ACID IN DIMETHYL SULFOXIDE
Authors: Miyakoshi Tetuo , Saito Shojiro , Kumanotani Ju 
Published: July 2006

Abstract
Dimerization of alkyl vinyl ketones in the presence of a catalytic amount of sodium nitrite-acetic acid in DMSO gave the corresponding 1,6-diketones in 58–86% yield.
REACTIONS OF CYCLIC ENAMINES WITH DICYANOMETHYLENECYCLOPROPENES. FORMATION OF MEDIUM RING COMPOUNDS AND TRANSANNULATION TO FULVENES
Authors: Tsuge Otohiko , Okita Shigeru , Noguchi Michihiko , Kanemasa Shuji 
Published: July 2006

Abstract
Several cyclic enamines with five to seven-membered rings react with 2-(1,2-diphenyl-3-cyclopropenylidene)propanedinitrile to give medium ring compounds, showing that the latter is a versatile reagent which can insert three carbon atoms between α- and β-carbons of cyclic enamines. These medium ring compounds undergo transannular reactions on treatment with hydrochloric acid to yield fulvene derivatives with the elimination of an amine component in the enamine.
CHROMATOGRAPHIC RESOLUTION OF TRIS(ACETYLACETONATO)COBALT(III) ON A Δ-TRIS(1,10-PHENANTHROLINE)NICKEL(II) MONTMORILLONITE COLUMN
Authors: Yamagishi Akihiko , Ohnishi Ryuichiro , Soma Mitsuyuki 
Published: July 2006

Abstract
Tris(acetylacetonato)Co(III) was partially resolved on a 2.5×1.5 cm o.d. chromatographic column of Δ-tris(1,10-phenanthroline)Ni(II) montmorillonite at 2°C. The percentage resolution of Λ-tris(acetylacetonato)Co(III) was attained to be 36% for the first eluted fraction.
KINETIC STUDY ON TWO TYPES OF NOVEL INTRAMOLECULAR REARRANGEMENTS OF HEPTA-COORDINATE OXOMOLYBDENUM(IV) COMPLEXES: MoO(S2CNEt2)2(EtOOCN=NCOOEt) AND MoO(S2CSPri)2(MeOOCC≡CCOOMe)
Authors: Kashiwagi Tohru , Tanaka Koji , Tanaka Toshio 
Published: July 2006

Abstract
A kinetic study reveals that the reaction of MoO(S2CNR2)2 with ROOCN=NCOOR (R = Me, Et) proceeds via two successive steps which consist of the formation of a mono-capped trigonal prismatic intermediate followed by intramolecular rearrangement, affording the final product with a pentagonal bipyramidal configuration. The entropy and the volume of activation in the rearrangement (R=Et) are both positive (ΔS\eweq=+38.0 J mol−1K−1, ΔV\eweq=+13.6 cm3mol−1), which are in marked contrast to the negative values for a similar rearrangement of MoO(S2CSPri)2(MeOOCC≡CCOOMe) (ΔS\eweq=−83.5 J mol−1K−1, ΔV\eweq=−9.9 cm3mol−1). Based on these results, two different mechanisms are suggested for the intramolecular rearrangement of hepta-coordinate molybdenum complexes.
BIOMIMETIC SHORT-STEP SYNTHESIS OF (±)-CASBENE FROM GERANYLGERANIOL
Authors: Toma Kazunori , Miyazaki Eiji , Murae Tatsushi , Takahashi Takeyoshi 
Published: July 2006

Abstract
(±)-Casbene was synthesized from all-trans geranylgeraniol by a route involving intramolecular carbene-olefin cyclization.
DOUBLE CARBONYLATION REACTIONS OF METHYL- AND PHENYLPALLADIUM(II) COMPLEXES IN THE PRESENCE OF SECONDARY AMINES AFFORDING α-KETO AMIDES
Authors: Ozawa Fumiyuki , Yamamoto Akio 
Published: July 2006

Abstract
The reactions of trans-PdR(X)(PMePh2)2 (R = Me, X = I and R = Ph, X = Br) with carbon monoxide in the presence of secondary amines, R’2NH, were found to give α-keto amides, RCOCONR’2, as double carbonylation products under mild conditions in good yields and selectivities.
CONSECUTIVE 1,3-DIPOLAR CYCLOADDITIONS OF CYCLOIMMONIUM YLIDES TO BENZYNE: FORMATION OF NOVEL 18π BENZO[a]ISOINDOLO[1,2,3-cd]INDOLIZINES
Authors: Matsumoto Kiyoshi , Uchida Takane , Sugi Takazumi , Yagi Yoshiko 
Published: July 2006

Abstract
Benzo[a] isoindolo [1,2,3-cd]indolizines, a novel kind of 18π heterocycles, have been prepared by one pot successive 1,3-dipolar cycloadditions of pyridinium dicyanomethylides with benzyne.
DECARBOXYLATION OF SODIUM GLYCIDATES: A CONVENIENT METHOD FOR THE SYNTHESIS OF α-ACETOXYKETONES, α-DIKETONES, AND α-KETOESTERS
Authors: Reutrakul Vichai , Srikirin Yupayao , Panichanun Sirichai 
Published: July 2006

Abstract
The decarboxylation of aryl sodium glycidates having substituent at the α-carbon gave the corresponding α-acetoxyketones, α-diketones and α-ketoesters in synthetically useful yields.
THE ABSOLUTE CONFIGURATION OF DIARYLHEPTANOID XYLOSIDE, OREGONIN, ISOLATED FROM THE FEMALE FLOWERS OF ALNUS SERRULATOIDES
Authors: Suga Takayuki , Ohta Shinji , Hirata Toshifumi , Aoki Tadashi 
Published: July 2006

Abstract
It was found that (−)-diarylheptanoid xyloside isolated from the female flowers of Alnus serrulatoides is 1,7-bis(3,4-dihydroxyphenyl)-5-(β-d-xylopyranosyloxy)-3-heptanone, and its spectral data and chemical behaviors coincides perfectly with those of previously reported oregonin whose absolute configuration had not been clarified yet. Then, the absolute configuration of the diarylheptanoid xyloside was investigated by a combination of the 13C NMR spectroscopy and the X-ray crystallography, and established to be s.
ASYMMETRIC SYNTHESIS OF OPTICALLY ACTIVE CYCLOHEXENOL DERIVATIVES VIA HIGHLY STEREOSELECTIVE REDUCTION OF (R)-3-(p-t-BUTYLPHENYLTHIO) CYCLOHEXAN-1-ONE
Authors: Suzuki Keisuke , Ikegawa Akihiko , Mukaiyama Teruaki 
Published: July 2006

Abstract
(R)-3-(p-t-Butylphenylthio)cyclohexan-1-one was reduced with LiAlH(OBut)3 to afford (1S,3R)-3-(p-t-butylphenylthio)cyclohexan-1-o1, while the same reduction with LiBH(s-Bu)3 afforded the (1R,3R) counterpart almost exclusively. Elaboration of each product furnished both enantiomers of optically pure cyclohexenol derivatives.
CHEMO- AND REGIOSELECTIVITIES IN ACID-CATALYZED RING EXPANSION OF 1-[1-METHYLSULFINYL-1-(METHYLTHIO)ALKYL]CYCLOBUTANOL DERIVATIVES
Authors: Ogura Katsuyuki , Yamashita Mitsuo , Suzuki Michiyo , Tsuchihashi Gen-ichi 
Published: July 2006

Abstract
A new ring expansion of the title compounds catalyzed by an acid was studied. The reaction of 2-methyl-1-[1-methylsulfinyl-1-(methylthio)alkyl]cyclobutanol was regio- and chemoselective to afford 3-methyl-2-(methylthio)cyclopentanone derivative.
PREPARATION OF MONOPHENYLTHALLIUM(III)DIBENZO-18-CROWN-6 COMPLEXES WITH A SOFT LIGAND: [C6H5Tl(DBC)X]ClO4
Authors: Kawasaki Yoshikane , Yokota Wataru , Enomoto Norihide 
Published: July 2006

Abstract
Monophenylthallium(III) complexes with a Tl–I or Tl–SR bond were prepared in the presence of dibenzo-18-crown-6. These complexes are stable in the air and to heat to their melting points. In the hydrogen sulfide complex, ν(S–H) band was found at 2570 cm−1 and δ(Tl–SH) was observed at 1.15 ppm with 2J(Tl-SH) = 405 Hz in CH2Cl2 solution.
REGIOSELECTIVE COPE REARRANGEMENT OF [2+2] CYCLOADDUCT OF 2-PHENYL-2-(1,2-DIPHENYL-3-CYCLOPROPENYLIDENE)ACETONITRILE TO AN ENAMINE LEADING TO PENTALENE DERIVATIVES
Authors: Tsuge Otohiko , Okita Shigeru , Noguchi Michihiko , Kanemasa Shuji 
Published: July 2006

Abstract
The reaction of 2-phenyl-2-(1,2-diphenyl-3-cyclopropenylidene)acetonitrile with 1-(1-pyrrolidinyl)acenaphthylene giving two isomeric tetrahydroindeno[1′,2′]cyclopenta[4,5-a]acenaphthylenes is the first example in which a phenyl group on the methylenecyclopropene ring took part in a cyclization: They are presumed to form via the regioselective Cope rearrangement of initially formed endo [2+2] cycloadducts followed by a hydrogen shift.
THE STRUCTURE OF POTAMOGETONIN
Authors: Hasegawa Shinichi , Hirose Yoshiyuki 
Published: July 2006

Abstract
By conversion of methyl 15,16-epoxy-20-oxo-8(17),13(16),14 labdatrien-19-oate (3) into 15,16-epoxy-8(17),13(16),14-labdatrien-19,20-olide (1) and 15,16-epoxy-8(17),13(16),14-labdatrien-20,19-olide (8), the structure of potamogetonin was proved to be 15,16-epoxy-8(17),13(16),14-ent-labdatrien-20,19-olide (10), not 1 as proposed by Smith et al.
HIGH EFFICACY OF SHORT CONTACT TIME PROCEDURE AT HIGH TEMPERATURE IN THE HYDROGEN TRANSFERRING LIQUEFACTION OF BROWN COAL
Authors: Mochida Isao , Otani Kazumasa , Korai Yozo , Fujitsu Hiroshi 
Published: July 2006

Abstract
Hydrogen transferring liquefaction of an Australian brown coal using pyrene hydrogenated with Li-ethylenediamine or a Ni–Mo catalyst is found very efficient to convert the coal hexane-soluble as well as benzene-soluble at yields as high as 70% and 90%, respectively, under the conditions of short contact time(1.5 min) at high temperatures (490–510°C). The structural differences of hydropyrenes are briefly discussed in relation with their performance in the liquefaction process of the present kind.
A NEW PROTECTING TACTICS FOR THE URACIL RESIDUE IN OLIGORIBONUCLEOTIDE SYNTHESIS
Authors: Kamimura Takashi , Masegi Tsukio , Urakami Ken-ichi , Honda Shinkichi , Sekine Mitsuo , Hata Tsujiaki 
Published: July 2006

Abstract
Four kinds of acyl groups as protecting group for the uracil imide functionhave been examined. Among them, the anisoyl group was found to be most promissing and used to demonstrate the synthesis of the dimer, UpUp.
SYNTHESIS AND EPIMERIZATION OF 11b-SUBSTITUTED-INDOLIZINO[8,7-b]INDOLE-5-CARBOXYLIC ACID METHYL ESTERS
Authors: Irikawa Hajime , Okumura Yasuaki 
Published: July 2006

Abstract
The methoxide-catalyzed epimerization at C-5 of the 11b-substituted-indolizino[8,7-b]indole-5-carboxylic acid methyl esters was in line with the stereochemical relationship of the substituent on C-11b and the methoxycarbonyl group on C-5.
STRUCTURES OF SESTERTERPENOIDS FROM THE SCALE INSECT CEROPLASTES CERIFERUS. REVISION OF THE 14-MEMBERED CERIFERENE SKELETON FROM 2-t/6-c/10-t TO 2-c/6-t/10-t
Authors: Pawlak Jan K , Tempesta Michael S , Iwashita Takashi , Nakanishi Koji , Naya Yoko 
Published: July 2006

Abstract
The structures of two new macrocyclic sesterterpenoids ceriferol-l 1 and ceriferic acid-1 2 isolated from the secretion of the scale insect Ceroplastes ceriferus were determined. The results led to the revision of the arrangement of annular double bonds in the carbon skeleton (from la to l) of all compounds correlated in the previous reports.
A FACILE OXIDATIVE LACTONIZATION OF 1,ω-DIOLS WITH SODIUM BROMITE
Authors: Kageyama Toshifumi , Kawahara Shuji , Kitamura Kohji , Ueno Yoshio , Okawara Makoto 
Published: July 2006

Abstract
A practically useful method for the oxidation of 1,ω-diols to lactones is described. The scope and limitations are also presented.
BENZYLATION OF ALCOHOLS TO BENZYL ETHERS WITH ALKALI CATION EXCHANGED Y TYPE ZEOLITE
Authors: Onaka Makoto , Kawai Motomitsu , Izumi Yusuke 
Published: July 2006

Abstract
Benzylation of alcohols with benzyl chloride is found to proceed efficiently in the presence of alkali cation exchanged Y type zeolite in a non-polar solvent under neutral conditions. The effects of solvent and alkali cation of zeolite are studied.
A SIMPLE SYNTHETIC METHOD OF DEOXYRIBODINUCLEOTIDE BLOCKS
Authors: Takaku Hiroshi , Kamaike Kazuo , Suetake Masanori 
Published: July 2006

Abstract
Deoxyribodinucleotide blocks can be prepared rapidly by combining the phosphorylation and coupling reaction steps in one flask which also contents the synthesis of deoxyribodinucleotide blocks containing the guanosine unit.
ABSORPTION SPECTRA OF VINYL CATIONS
Authors: Kobayashi Shinjiro , Kitamura Tsugio , Taniguchi Hiroshi , Schnabel Wolfram 
Published: July 2006

Abstract
The absorption spectra of α-(p-methoxyphenyl)vinyl cations were measured by laser flash photolysis of the corresponding vinyl halides in acetonitrile and the nucleophilicity of several alcohols to the vinyl cations was evaluated by measuring the decay rates in the presence of the alcohols.
PREPARATION OF ENANTIOMERICALLY PURE 1-HYDROXY-NEOCEMBRENES TO DETERMINE THE UNSOLVED ABSOLUTE CONFIGURATION OF CEMBRENOIDS
Authors: Aoki Mario , Uyehara Tadao , Kato Tadahiro , Kabuto Kuninobu , Yamaguchi Shozo 
Published: July 2006

Abstract
Cis and trans 1-hydroxy-neocembrenes were prepared in an enantiomerically pure form by reduction of dl-ketone with respective (+)- and (−)-Darvon-LiAlH4 complex followed by purification with the aids of esterification with d- and l-menthoxyacetyl chlorides and (−)-camphanic acid chloride, respectively. Absolute configuration of naturally occurring (+)-mayol and (+)-cembrenene was determined by correlation with enantiomerically pure compounds.