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Volume 43, Issue 1
Displaying 1-35 of 35 articles from this issue
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Akira SHIBATA, Junya KOHARA, Satoru UENO, Takuya YAMASHITA1995 Volume 43 Issue 1 Pages 1-4
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe structural changes of bacteriorhodopsin (bR) in purple membrane (PM) at the air-water interface and the effects of monovalent cations were examined using a monolayer technique and Fourier transform IR spectroscopy. The low initial coverage (ci) of the interface with PM films significantly caused the denaturation of bR accompanied by a collapse in the PM bilayer structure. The IR spectra of LB films of the PM monolayer films showed that the α-helical bR molecule in the PM film was partially transformed into a β-sheet depending on the ci value. The surface pressure-area (π-A) isotherms of the PM films in the presence of 50 mM alkali metal chlorides were condensed in the sequence Cs+>K+>Na+>Li+. The α-helix content of bR in the PM films in the presence of 50 mM alkali metal chloride was 84.3% for Cs+, 83.5% for K+, 78.9% for Na+, and 76.0% for Li+, comparable to 68.2%, the value for the subphase ion-free water. The present data indicated that the unfolding of the α-helical bR in the PM monolayer films was depressed by the addition of small amounts of monovalent cations into the subphase water.View full abstractDownload PDF (715K) -
Kenji SHIOJIMA, Masayoshi SUZUKI, Hiroshi AOKI, Hiroyuki AGETA1995 Volume 43 Issue 1 Pages 5-8
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFom the fresh leaflets of a fern, Gleichenia japonica, four new labdane-type diterpenoid glycosides, 18-O-α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranosyl-13-epitorreferol (1), 3-O-α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranosyl-3β-hydroxymanool (2), 3-O-α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranosyl-3β-hydroxy-13-epimanool (3), and 3-O-α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranosyl-(13E)-labda-8(17), 13-diene-3β, 15-diol (4), were isolated together with two known compounds, (6S, 13S)-6-O-α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranosyl-6, 13-dihydroxycleroda-3, 14-diene (5) and 3-O-β-D-glucopyranosyl-13-O-α-L-rhamnopyranosyl-3β-hydroxymanool (6), and their structures were determined.View full abstractDownload PDF (587K) -
Reiko MIZUNO, Nobuo KAWAHARA, Koohei NOZAWA, Mikio YAMAZAKI, Shoichi N ...1995 Volume 43 Issue 1 Pages 9-11
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAn 18, 22-cyclosterol, Mer-NF8054X (1), first isolated from a shaken culture of Aspergillus ustus as a strong antifungal agent with activity against Aspergillus fumigatus, was isolated from the culture filtrate of Emericella heterothallica. The absolute structure of 1 was established as 11-oxo-18, 22-cycloergosta-6, 8(14)-diene-3β, 5β, 9β, 23S-tetraol by spectroscopic and chemical investigation, and X-ray crystallographic analysis.View full abstractDownload PDF (456K) -
Hirokazu TAMAMURA, Akira OTAKA, Wataru TAKADA, Yoshihiro TERAKAWA, Hid ...1995 Volume 43 Issue 1 Pages 12-18
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESST22 ([Tyr5, 12, Lys7]-polyphemusin II) was previously synthesized by a solid-phase method and was found to have a strong anti-human immunodeficiency virus (HIV) activity, comparable to that of 3'-azido-2', 3'-dideoxy-thymidine (AZT). In the present study, the solution-phase synthesis of T22 was attempted in order to produce this peptide on a large scale. An 18-residue peptide amide corresponding to the entire amino acid sequence of T22 was synthesized by assembling four peptide fragments and two amino acid derivatives, followed by thioanisole-mediated deprotection with 1 M trimethylsilyl trifluoromethanesulfonate (TMSOTf) in trifluoroacetic acid followed by air-oxidation. During this deprotection, a significant by-product derived from the transfer of the p-methoxybenzyl (MBzl) group from the sulfhydryl group of the cysteine residue to the side chain of the tryptophan residue was formed. This side reaction was found to be efficiently suppressed by adopting a two-step deprotection procedure using silver trifluoromethanesulfonate (AgOTf)-TMSOTf or trimethylsilyl bromide (TMSBr)-TMSOTf.View full abstractDownload PDF (1115K) -
Haruki SASHIDA, Koichi ITO, Takashi TSUCHIYA1995 Volume 43 Issue 1 Pages 19-25
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSNovel 2-alkyl-1-benzotellurepines (11) and 2-alkyl-1-benzoselenepines (12) were obtained by sodium borohydride reduction of di[o-(1-buten-3-ynyl)phenyl] ditellurides (8) and diselenides (9), together with 2-alkylidene-2H-tellurachromenes (13) and 2-alkylidene-2H-selenachromenes (14), respectively, via the phenyltellurol and phenylselenol intermediates (10). The dimers (8, 9) were readily prepared from the 4-alkyl-1-(o-bromophenyl)-1-buten-3-ynes (7) by successive treatment with tert-butyllithium, tellurium or selenium powder, and potassium ferricyanide in one pot. The 2-alkyl-1-benzothiepines (16) were obtained directly from the enynes (7) by successive treatment with tert-butyllithium, sulfur powder, and ethanol in one pot. To examine the chemical behavior of the novel tellurepine ring, several reactions of 2-tert-butyetellurepine (11c) weree carried out.View full abstractDownload PDF (1025K) -
Masashi OHBA, Tsuyoshi HANEISHI, Tozo FUJII1995 Volume 43 Issue 1 Pages 26-31
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFormal syntheses of (±)-boschnialactone (5) and three cyclopentano-monoterpene lactones [i.e., (±)-iridomyrmecin (6), (±)-isoiridomyrmecin (7), and (±)-allodolicholactone (8)] have been accomplished in the form of the syntheses of 2-(methoxymethyl)-3-methyl-2-cyclopenten-1-one (11) and (±)-(4aα, 7α, 7aα)-hexahydro-7-methylcyclopenta[c]pyran-3(1H)-one (19), respectively, starting from 6, 7-dihydrocyclopenta-1, 3-dioxin-5(4H)-one (2). A synthesis of (±)-isodehydroiridomyrmecin (9) has also been achieved through a route including direct substitution of the hydroxy group of 2-(tert-butyldimethylsilyloxymethyl)-3-methyl-2-cyclopenten-1-ol (22) with 1-(tert-butyldimethylsilyloxy)-1-methoxyethene (23) as a key step.View full abstractDownload PDF (1054K) -
Shigeko OZAKI, Hidenori MATSUSHITA, Miho EMOTO, Hidenobu OHMORI1995 Volume 43 Issue 1 Pages 32-36
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSNickel(II) complex-catalyzed indirect electroreduction of N-allyl and N-propargyl-α-bromoamides conducted in dimethylformamide with 2 eq of a hydrogen atom donor, diphenylphosphine, afforded the corresponding pyrrolidinones as the sole cyclized product in good yields, while that of N-allyl-α-iodoamides in acetonitrile gave the iodinated pyrrolidinones. Under both conditions the trans-C-3 : C-4 pyrrolidinones were formed predominantly.View full abstractDownload PDF (757K) -
Iwao UTSUNOMIYA, Hideaki MURATAKE, Mitsutaka NATSUME1995 Volume 43 Issue 1 Pages 37-48
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAn acid-catalyzed indole formation reaction previously reported by us was successfully applied to the preparation of variously substituted 4-hydroxy-1H-indoles 11a-g having carbon and/or heteroatom substituents at the benzene portion of the indole ring, using as substrates 3-(4, 4-dialkoxy-1-oxobutyl)-1H-pyrroles 10a-g, which are readily available from simple pyrroles in several steps. Employing one of these indoles, 11g, as a starting intermediate, an enantiospecific synthesis of the mitosene analogues 8, 9a and 9b related to antitumor antibiotics FR 900482 (1) and FR 66979 (2) was achieved by i) condensation of 20 with a chiral aldehyde 21, ii) transformation of 22a and 22b into the tricyclic compounds 29a and 29b, iii) introduction of the additional one-carbon unit as a formyl group, iv) formation of the aziridine ring, and v) removal of the benzyl protecting group. Elimination of the tert-butyloxycarbonyl group was also examined to provide the basis for a future project to synthesize 5a, the cross-linkage product of 2 and DNA.View full abstractDownload PDF (2157K) -
Tozo FUJII, Masashi OHBA, Shigeki SETO1995 Volume 43 Issue 1 Pages 49-52
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA detailed account is given of the first chiral synthesis of the Ophiorrhiza alkaloid ophiorrhizine [(-)-1]. The synthesis was started by coupling the lactim ether (+)-4, readily available from cincholoipon ethyl ester [(+)-3], with 6-benzyloxy-3-chloroacetylindole (6) to form the lactam ketone (+)-8 and proceeded through the intermediates (+)-9, (+)-10, 11, (-)-12, (-)-13, 14, (-)-15, and (-)-16. The identity of synthetic (-)-1·H2O with natural ophiorrhizine unequivocally established the absolute stereochemistry of this alkaloid.View full abstractDownload PDF (793K) -
Tozo FUJII, Kazuo OGAWA, Tohru SAITO, Keiko KOBAYASHI, Taisuke ITAYA, ...1995 Volume 43 Issue 1 Pages 53-62
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA detailed account is given of the first unequivocal synthesis of adenine 7-oxide (8). The synthesis started with peroxycarboxylic acid oxidation of 3-benzyladenine (6), readily obtainable from adenine (1) by benzylation, and proceeded through nonreductive debenzylation of the resulting 3-benzyladenine 7-oxide (7). The location of the oxygen function in 7 and 8 was confirmed by their chemical reactions including deamination and methylation and by X-ray crystallographic analysis. A UV spectroscopic approach suggested that the neutral species of 8 exists in H2O as an equilibrated mixture of the N(7)-oxide (8) and N(7)-OH (21) tautomers. Treatment of 6 with 30% aqueous H2O2 in MeOH in the presence of MeCN and KHCO3 at 30°C produced the N(7)-oxide 7 and 7-acetamido-3-benzyladenine (15) in 12% and 1% yields, respectively.View full abstractDownload PDF (1493K) -
Jun SEGAWA, Kenji KAZUNO, Masato MATSUOKA, Ichiro SHIRAHASE, Masakuni ...1995 Volume 43 Issue 1 Pages 63-70
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA seried of 1, 8-disubstituted 6-fluoro-4-oxo-7-piperazinyl-4H-[1, 3]thiazeto[3, 2-a]quinoline-3-carboxylic acid derivatives was prepared and evaluated for antibacterial activity. In the 7-piperazinyl series, addition of a fluorine at C-8, which increased the in vitro activity for the 1-hydrogen and 1-methyl analogues and decreased it for the 1-phenyl analogue, improved the in vivo activity of all the analogues. Introduction of a methoxy group at C-8 of the 1-methyl-7-piperazinyl analogue also improved its in vivo antibacterial activity. The effect of 8-substituents on the in vitro and in vivo antibacterial activity of the 1-methyl-7-(4-methyl-1-piperazinyl) series is also discussed.View full abstractDownload PDF (1079K) -
Kiyoshi TANIGUCHI, Kazuo OKUMURA, Kazuhiko TAKE, Kazunori TSUBAKI, Tak ...1995 Volume 43 Issue 1 Pages 71-77
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThis article describes the synthesis of 4, 4-diphenyl-2-cycloalkenylamines (3, 5a) including FK584 (S(-)-3a) and 3, 3- or 4, 4-diphenylcycloalkylamines (2, 4, 5b), and their inhibitory activities against detrusor contraction. The order of inhibitory activity (i.v.) of the N-tert-butylamine derivatives against urinary bladder rhythmic contraction in rats was as follows : S(-)-4, 4-diphenyl-2-cyclopentenylamine (FK584, S(-)-3a)>4, 4-diphenylcyclohexylamine (5b)=R(-)-3, 3-diphenylcyclopentylamine (R(-)-4)≥3, 3-diphenylcyclobutylamine (2)≥terodiline hydrochloride (HCl)(1)=RS(±)-4, 4-diphenyl-2-cyclohexenylamine (5a)>R(+)-4, 4-diphenyl-2-cyclopentenylamine (R(+)-3a)≥S(+)-3, 3-diphenylcyclopentylamine (S(+)-4). Although the inhibitory activity of FK584 and compounds R(-)-4 and 5b against detrusor contraction in vitro induced with KCl in guinea-pigs was less potent than that of terodiline HCl, their inhibitory activities against detrusor contractions in vitro induced by electrical field stimulation and carbachol were more potent than those of terodiline HCl.View full abstractDownload PDF (989K) -
Masashi HASEGAWA, Atsushi NAKAYAMA, Toru HOSOKAMI, Yoichi KUREBAYASHI, ...1995 Volume 43 Issue 1 Pages 78-83
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA series of bicyclic thiazoline derivatives (4a-s) was synthesized and evaluated for hepatoprotective activity against galactosamine-induced and monoclonal antibody-induced acute liver injuries in rats. The structure-activity relationships were investigated. Among the compounds synthesized, ethyl 3-(N-methylcarbamoyl)-5, 6-dihydrothiazolo[2, 3-c][1, 4]thiazine-8-carboxylate (4p) exhibited remarkable hepatoprotective activity and lower toxicity. This compound suppressed galactosamine-induced hepatic injury at 100 mg/kg by gavage and further prevented monoclonal antibody-induced hepatic injury at 30 mg/kg by intraperitoneal injection, as evaluated by measuring changes in serum transaminase activities.View full abstractDownload PDF (875K) -
Shirou MAEDA, Hiroshi MASUDA, Takashi TOKOROYAMA1995 Volume 43 Issue 1 Pages 84-90
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe oxidative coupling reaction of the hydroxycinnamate 11 derived from daphnetin has been investigated. The reaction with silver oxide afforded, after acetylation, a dihydrobenzofuran derivative 17 and a benzodioxane derivative 16a as major products accompanied with a small amount of a bis(benzylidene) succinate 18 and a dihydronaphthalene 19, while the oxidation with iron(III) chloride gave the dihydronaphthalene derivative 20 corresponding to 19. The reaction with potassium hexacyanoferrate(III) and Na2CO3 produced, after acetylation, 16a and 19 in lower yields. The propensity for product formation in the reaction of 11 is discussed in relation to data for the reactions of hydroxycinnamate derivatives studied so far.The obtained compounds were tested for inhibitory effects on lipid peroxidation in rat brain homogenate and rat liver microsomes. In the rat brain homogenate the five compounds showed inhibitory activity more potent than that of idenbenone. Compounds 17 and 20 were then tested in rat liver microsomes, and found to be more potent than schizotenuin A and much more potent than (±)-α-tocopherol.View full abstractDownload PDF (945K) -
Yoshiko SATO, Tokumi MARUYAMA1995 Volume 43 Issue 1 Pages 91-95
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new procedure for the synthesis of 3'-fluorocarbocyclic oxetanocin A (1b) was developed. Addition of iodine fluoride to O-cyclohexylidene-cis-2-hydroxymethyl-3-methylene-1-cyclobutanol (4) afforded O-cyclohexylidene-(1S*, 2S*, 3R*)-3-fluoro-3-iodomethyl-2-hydroxymethyl-1-cyclobutanol (5) and the undesired (1S*, 2S*, 3S*)-isomer (6) in 6.2% and 38% yields, respectively. When fluorine was introduced into the carbocycle after condensation of 6-chloropurine, 6-chloro-9-[(1R*, 2S*, 3R*)-3-fluoro-3-iodomethyl-2-(trityloxymethyl)cyclobutyl]purine (10) was obtained as a sole addition product, which was readily converted to 1b. This compound (1b) exhibited a broad spectrum of antiviral activity, especially against human cytomegalovirus.View full abstractDownload PDF (840K) -
Yoshio OKADA, Yuko TSUDA, Yu MU, Kenichi HIRANO, Hiroshi OKAMOTO, Yosh ...1995 Volume 43 Issue 1 Pages 96-99
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSBased on the results of X-ray analysis of the complex between Suc-Gln-Val-Val-Ala-Ala-pNA, a fairly potent thiol proteinase inhibitor, and papain, iNoc-Gln-Val-Val-Ala-Ala-pNA was designed and prepared and its inhibitory activity against thiol proteinases was examined. iNoc-Gln-Val-Val-Ala-Ala-pNA inhibited cathepsin L fairly specifically, although its potency is not high.View full abstractDownload PDF (625K) -
Hideo SHIMASAKI, Hiroyuki KAGECHIKA, Hiroshi FUKASAWA, Emiko KAWACHI, ...1995 Volume 43 Issue 1 Pages 100-107
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSeveral retinoid candidates which possess an amide bond at the position corresponding to the 9-ene part of retinoic acid (1) were synthesized and their conformations and biological activities were investigated. N-(Methoxycarbonyl)dienamines, prepared by the rearrangement of dienoic acid azides trapped by methanol, were condensed with acid chlorides, followed by removal of the methoxycarbonyl group and hydrolysis of the ester group to afford the secondary dienamides, N-(2, 6, 6-trimethyl-1-cyclohexen-1-yl)muconamic acid (7a), 5-[[3-(2, 6, 6-trimethyl-1-cyclohexen-1-yl)-2-propenoyl]amino]-2, 4-pentadienoic acid (8a), and 4-[N-[2-[2, 6, 6-trimethyl-1-cyclohexen-1-yl)ethenyl]carbamoyl]benzoic acid (26a). The tertiary amide derivatives were also prepared by N-methylation of the secondary amides. NMR studies indicated that the secondary dienamides exist predominantly in trans-amide form in solution, like the potent retinoidal aromatic amide, 4-[(5, 6, 7, 8-tetrahydro-5, 5, 8, 8, -tetramethyl-2-naphthalenyl)-carbamoyl]benzoic acid (Am80). N-Methylation of the secondary amides resulted in cis-amide preference in solution. The biological activities of these amides were examined in terms of the differentiation-inducing activity towards human promyelocytic leukemia cell line HL-60.View full abstractDownload PDF (1231K) -
Ryoichi KIZU, Takeshi YAMAMOTO, Tohru YOKOYAMA, Makiko TANAKA, Motoich ...1995 Volume 43 Issue 1 Pages 108-114
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA sensitive postcolumn derivatization/UV detection system has been developed for HPLC analysis of antitumor divalent and quadrivalent platinum complexes. It is based on the derivatization of platinum complexes by reaction with sodium bisulfite to cerresponding product(s) which has enhanced absorptivity at 280-300 nm. Platinum complexes examined in this study were cisplatin, carboplatin and oxaliplatin (divalent platinum complexes) and oxoplatin and tetraplatin (quadrivalent ones). The proposed detection system was sensitive to all these complexes. Under the detection conditions optimized for individual complexes, the HPLC gave linear relationships between the complex concentration and the peak height. Detection limits at 290 nm with 100 μl injection were 20 nM for cisplatin, 40 nM for oxoplatin, 60 nM for carboplatin and tetraplatin and 100 nM for oxaliplatin (S/N=3 at 0.005 AUFS). The proposed system was successfully applied for the determination of cisplatin and oxoplatin in plasma and urine. Pharmacokinetic behavior of oxoplatin and its reduced product cisplatin following a single intravenous injection of oxoplatin in rabbits has been discussed.View full abstractDownload PDF (969K) -
Dongming ZHANG, Toshio MIYASE, Masanori KUROYANAGI, Kaoru UMEHARA, Aki ...1995 Volume 43 Issue 1 Pages 115-120
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTen new oleanane-type saponins, polygalasaponins I-X, along with two known saponins, bayogenin-3-O-β-D-glucopyranoside and lobatoside B were isolated from the aerial part of Polygala japonica HOUTT. The structures of these compounds were established on the basis of spectroscopic and chemical evidence.View full abstractDownload PDF (821K) -
Yukinobu IKEYA, Ko SUGAMA, Masahide TANAKA, Takeshi WAKAMATSU, Hiromas ...1995 Volume 43 Issue 1 Pages 121-129
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAfter oral administration of schizandrin (1) to rat, the bile was collected and treated with β-glucuronidase and arylsulfatase. Eleven metabolites, SZ-M0 (3), SZ-M1 (4), SZ-M2 (5), SZ-M3 (6), SZ-M4 (7), SZ-M5 (8), SZ-M6 (9), SZ-M7 (10), SZ-M8 (11), SZ-M9 (12) and SZ-M10 (13) were isolated from the bile treated with the enzymes. The bile after oral administration of 1 to dog was collected and treated with enzymes in the same way, and eight metabolites, 3-8, 10 and SZ-MD2 (14) were isolated from the bile treated with enzymes. The structures of these metabolites were determined on the basis of chemical and spectral studies. The major metabolite in the bile of rat was 7 and the major metabolites in the bile of dog were 7 and 14.View full abstractDownload PDF (1227K) -
Fumitoshi HIRAYAMA, Masayuki YAMANAKA, Takashi HORIKAWA, Kaneto UEKAMA1995 Volume 43 Issue 1 Pages 130-136
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new series of peracylated β-cyclodextrins (β-CyDs) with different alkyl chains (acetyl-lauroyl) was prepared in high purity by acylating all hydroxyl groups of β-CyD using acid anhydrides in pyridine, and their physicochemical properties of solubility, hydrolsis and release and interaction capacity were evaluated. The solublity of peracylated β-CyDs in water decreased with lengthening alkyl chain, whereas that in ethanol/water increased with increase in ethanol concentration, but tended to decrease at higher ethanol concentration. The solubility parameter of peracylated β-CyDs was determined by analyzing the peak-solubility phenomenon by a modified Hildebrand equation. The alkaline hydrolysis rate of peracylated β-CyDs decreased with lengthening alkyl chain, and was about 4-fold faster than that of the corresponding fatty acid ethyl esters. The interaction of perbutanoyl-β-CyD (TB-β-CyD) with a water-soluble drug, molsidomine, in the solid state was investigated by differential scanning calorimetry (DSC). The analysis of DSC curves suggested that molsidomine and TB-β-CyD form a binary solid dispersion with a 2 : 1 (drug : TB-β-CyD) molar ratio. The rate of drug release was markedly retarded by the combination with peracylated β-CyDs in the increasing order of the hydrophobicity of host molecules.View full abstractDownload PDF (957K) -
Kei-ichi SAMUKAWA, Hideyuki YAMASHITA, Hideaki MATSUDA, Michinori KUBO1995 Volume 43 Issue 1 Pages 137-141
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe presence of about 25 ginsenosides in Ginseng Radix and their structures have already been elucidated. Although some important neutral- and acidic-saponins have been detected by high performance liquid chromatography (HPLC), other saponins have not yet been examined by HPLC. Our present improved method for the detection of ginsenosides by HPLC with a C18 column and a CH3CN-H2O gradient system enabled the measurement of not only the representative ginsenosides in Red Ginseng [20(R)-ginsenoside-Rg2 and -Rh1, 20(S, R)-ginsenosides-Rg3 and -Rs1] but also the minor ginsenosides [ginsenosides-Rb3, -Rg2, -Rh1 and quinquenoside-R1]. Furthermore, the application of this method after a little modification of the eluent in particular to an extract of Ginseng Radix achieved simultaneous separation of 22 neutral- and acidic-ginsenosides. The qualitative and quantitative analysis of ginsenosides using the present method offers an efficient means of evaluating Ginseng Radix and commercial products containing it.View full abstractDownload PDF (577K) -
Masaru UBASAWA, Hideaki TAKASHIMA, Kouichi SEKIYA1995 Volume 43 Issue 1 Pages 142-143
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSBis(trimethylsilyl)pyrimidine bases were treated directly with 1, 3-dioxolane (or 2-methyl-1, 3-dioxolane), chlorotrimethylsilane and a metal iodide, such as KI or NaI, in acetonitrile at room temperature to afford acylopyrimidine derivatives, including 2-thiopyrimidine derivatives, in good yields. Introduction of an acyclic chain into 2-thiopyrimidine bases, however, necessitated the use of 2 eq of the reagents.View full abstractDownload PDF (405K) -
Shao Shun LI, Xue Long SUN, Haruo OGURA, Yaeko KONDA, Tomomitu SASAKI, ...1995 Volume 43 Issue 1 Pages 144-146
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe phorochemical reactions of 3', 5'-dibenzoyl-2'-deoxyuridine and -thymidine with 2, 3-dimethyl-2-butene by upon ultraviolet (UV) irradiation in acetone have been investigated. Each reactant gave a pair of diastereomers in good yield. After recrystallization, mixed crystals of diastereomers could by isolated and purified. An X-ray analysis of a mixed crystal of the thymidine derivative (3b) showed a pair of diastereomers (A and B) composing a unit cell.View full abstractDownload PDF (530K) -
Tsutomu SUGAHARA, Osamu YAMADA, Ikuko SATOH, Seiichi TAKANO1995 Volume 43 Issue 1 Pages 147-151
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTotal syntheses of the title compounds were achieved from the optically active (+)-Corey lactone alcohol (5).View full abstractDownload PDF (740K) -
New Route to 1-(5-Imidazolyl)ribofuranoid Glycals from Ribofuranosyl Chloride and 5-Lithio-imidazoleShinya HARUSAWA, Masayo KAWABATA, Yoshihiko MURAI, Ryuji YONEDA, Takus ...1995 Volume 43 Issue 1 Pages 152-155
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSReaction of ribofuranosyl chlorides with 2 eq of 5-lithio-imidazole afforded 1-(5-imidazolyl)ribofuranoid glycals in good yields. Hydrolysis of the glycal (3) with hydrochloric acid led to 4-(5-hydroxymethylfuran-2-yl)imidazole (7), which contains both hydrophilic and hydrophobic aromatic heterocycles.View full abstractDownload PDF (612K) -
Ryuichiro TANAKA, Atsutoshi HASHIMOTO, Naoki NODA, Kazumoto MIYAHARA1995 Volume 43 Issue 1 Pages 156-158
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTen choline glucerophospholipids (CGP) were isolated from the marine annelid, Marphysa sanguinea. Among them, six compounds were lyso platelet-activating factors (PAFs) and two were 1-hexadecyl-2-arachidonoyl-and 1-hexadecyl-2-eicosapentanoyl-sn-glycero-3-phosphocholines, which are regarded as stored precursor forms of PAF, so-called PAF-like lipid. These two compounds comprised 28% of the alkylacyl CGP fraction and are considered to be the main components of PAF-like lipid in this material.View full abstractDownload PDF (646K) -
Kunihiko MOHRI, Kazumi SUZUKI, Masumi USUI, Kimiaki ISOBE, Yoshisuke T ...1995 Volume 43 Issue 1 Pages 159-161
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSN-Alkylation of secondary amines with alkyl halides in the presence of potassium hydride and triethylamine gave corresponding tertiary amines in satisfactory yields.View full abstractDownload PDF (452K) -
Michel BOULOUARD, Josette LOUCHAHI-RAOUL, Florence HEUDE, Marie-Anne Q ...1995 Volume 43 Issue 1 Pages 162-165
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSNew thienyldihydropyridines were synthesized according to Hantzsch's method. The antihypoxic activity of these compounds was compared with that of three reference phenyldihydropyridines by means of the skin conductance reaction (SCR)-hypoxia test.View full abstractDownload PDF (635K) -
Kohji TERASHIMA, Hiroshi SHIMAMURA, Akito KAWASE, Yuji TANAKA, Keiji U ...1995 Volume 43 Issue 1 Pages 166-168
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSEthyl 2-[(1H-benzimidazol-2-yl)sulfinylmethyl]-4-dimethylamino-5-pyrimidinecarboxylate (2) has been synthesized and evaluated for antiulcer properties. Compound 2 is a H+/K+-ATPase inhibitor that affords mucosal protection against absolute ethanol-induced gastric lesions in rats after oral and parenteral administrations. On the other hand, omeprazole, a representative H+/K+-ATPase inhibitor, showed mucosal protective action only after oral administration, indicating that it required gastric acid secretion to generate activity. The antiulcer activity of 2 in animal models, such as water-immersion stress-induced gastric ulcer in rats and acidified aspirin-induced gastric ulcer in rats, was three times higher than that of cimetidine.View full abstractDownload PDF (576K) -
Yoshiteru OSHIMA, Setsu MATSUOKA, Yasushi OHIZUMI1995 Volume 43 Issue 1 Pages 169-170
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA methanol extract of the roots of Valeriana fauriei (Valerianaceae), exhibited antidepressant activity in mice. The extract was fractionated, monitored by the activity, to afford α-kessyl alcohol as an active principle. The antidepressant activity of some guaiane and valerane types of sesquiterpenoids in the active fraction was also evaluated.View full abstractDownload PDF (406K) -
Shinji NAGUMO, Isao UMEZAWA, Junko AKIYAMA, Hiroyuki AKITA1995 Volume 43 Issue 1 Pages 171-173
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSN-Trifluoroacetyl-L-acosamine 20 and N-trifluoroacetyl-L-daunosamine 21 were formally synthesized from an achiral precursor, methyl sorbate 4, based on enzymatic chiral induction and diastereoselective 1, 4-conjugated addition of benzylamine to the olefinic moiety of the α, β-unsaturated ester 12.View full abstractDownload PDF (507K) -
Akira MIYASHITA, Yasushi SATO, Sayuri WATANABE, Ken-ichi TANJI, Takeo ...1995 Volume 43 Issue 1 Pages 174-176
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSLithiation of 3-(4, 4-dimethyl-2-oxazolin-2-yl)pyrazolo[1, 5-a]pyridine (1a) with 2 molar equivalents of n-BuLi followed by reaction with benzaldehyde yielded α-(4, 4-dimethyl-2-oxazolidinylidene)-6-(α-hydroxybenzyl)-2-pyridineacetonitrile (2a). Upon similar treatment of other electrophiles, the corresponding 2, 6-disubstituted pyridines 2 were produced. The formation of the pyridines proceeded through lithiation, reaction with an electrophile, and ring-cleavage of the pyrazole ring.View full abstractDownload PDF (408K) -
Yoshihiro SHIBATA, Mizue SHICHITA, Keizo SASAKI, Koji NISHIMURA, Yuich ...1995 Volume 43 Issue 1 Pages 177-179
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSPhthalimide analogs N-substituted with n-butyl, (tert)___--butyl, hexyl and adamantyl groups were designed and prepared as simplified analogs of thalidomide and methylthalidomide. All the compounds prepared except N-n-butylphthalimide showed thalidomidal activity on 12-0-tetradecanoylphorbol-13-acetate-induced tumor necrosis factor (TNF)-α production by human leukemia HL-60 cells. Among the investigated compounds, including thalidomide and methylthalidomide, N-adamantylphthalimide showed the most potent TNF-α production-enhancing activity.View full abstractDownload PDF (414K) -
Kenji SHIOJIMA, Hideki SUZUKI, Nobuyuki KODERA, Hiroyuki AGETA, Hsien- ...1995 Volume 43 Issue 1 Pages 180-182
Published: January 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA novel triterpenoid, ixerenol (1), has been isolated together with twelve known triterpenoid alcohols as acetates; its structure was determined by extensive spectroscopic analyses.View full abstractDownload PDF (402K)
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