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Volume 45, Issue 3
Displaying 1-33 of 33 articles from this issue
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EL-NADER ABU, Mohamed Hamed1997 Volume 45 Issue 3 Pages 427-430
Published: March 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe kinetics of the double exchange of ligands between Mn bipy2+ or Mn phen2+ and a trisoxalatocobaltate(III) complex was studied in dimethylformamide (DMF)-water media. The reaction kinetics were followed spectrophotometrically in the temperature range of 20-40±0.1°C. The rates of the reactions were found to decrease with increasing DMF in the medium. The solvent effect on the reaction rate was discussed in terms of the dielectric constant of the medium and the thermodynamic properties of activation. A chain mechanism was proposed to account for the exchange process.View full abstractDownload PDF (560K) -
Atsuomi KIMURA, Naohito KUNI, Hideaki FUJIWARA1997 Volume 45 Issue 3 Pages 431-436
Published: March 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS^<23>Na-NMR spectroscopy has been applied to study the transport of Na+ ions across unilamellar vesicle membranes mediated by ionophores. The ionophores used were amphotericin B and nystatin. Also, monensin, lasalocid A and gramicidin D were included for the sake of comparison since the transport processes of these ionophores are well characterized as carrier-, and carrier- channel-types, respectively. The 23Na-NMR techniques employed were 2D-EXSY (exchange spectroscopy) and the 1D time-course monitoring techniques, and the measurement exchange rates. These techniques were also applied at different temperatures, and the activation parameters were determined for the ionophore-mediated Na+ exchange. These activation parameters disclosed an unusual behavior of amphotericin B and nystatin. That is, cation transport through the membrane is decreased on increasing the temperature of measurement, resulting in negative values for the apparent enthalpy of activation. Such unusual behavior is related to the fluidity of the model membrane and to intermolecular interactions in the membrane.View full abstractDownload PDF (902K) -
Kazuhito OGIHARA, Rieko YAMASHIRO, Matsutake HIGA, Seiichi YOGI1997 Volume 45 Issue 3 Pages 437-445
Published: March 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSVarious naphthoquinone derivatives were prepared from a natural product, 5-hydroxy-2-methyl-1, 4-naphthoquinone (plumbagin); these were mostly substituted at C-3 through carbon-carbon bond formation mediated by a metal-based oxidant such as lead tetraacetate in the presence of various carboxylic acids. The halogenated compounds showed stronger ichthyotoxicity than plumbagin, but other derivatives were less active.View full abstractDownload PDF (1148K) -
Tokunaru HORIE, Kenichi SHIBATA, Kazuyo YAMASHITA, Yasuhiko KAWAMURA, ...1997 Volume 45 Issue 3 Pages 446-451
Published: March 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe demethylation of 3, 4-dioxygenated 6-methoxy-2-isopropoxyacetophenones was studied and it was found that 4-benzyloxy-6-hydroxy-3-methoxy-2-isopropoxyacetophenone was easily obtained from 4-benzyloxy-3, 6-dimethoxy-2-isopropoxyacetophenone by selective demethylation with anhydrous aluminum bromide-sodium iodide in acetonitrile. The acetophenone was converted into 7-benzyloxy-3-hydroxy-6-methoxy-5-isopropoxyflavones by cyclization followed by oxidation with dimethyldioxirane. The isopropoxy group in the flavones was selectively cleaved with anhydrous aluminum chloride via the corresponding tosylates to give 7-benzyloxy-3, 5-dihydroxy-6-methoxyflavones, which were converted into the desired 3, 5, 7-trihydroxy-6-methoxyflavones by hydrogenolysis. The process was suitable as a general method for synthesizing 3, 5, 7-trihydroxy-6-methoxyflavones and five flavones were synthesized. We also examined the 13C-NMR spectra of twelve kinds of 3, 5, 6, 7-tetraoxygenated 4'-methoxyflavones and revised the proposed structure of a natural flavone.View full abstractDownload PDF (888K) -
Yoshio OKADA, Jidong WANG, Takeshi YAMAMOTO, Toshio YOKOI, Yu MU1997 Volume 45 Issue 3 Pages 452-456
Published: March 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSNα-tert-Butyloxycarbonyl-Nπ-2-adamantyloxymethylhistidine, Boc-His(Nπ-2-Adom)-OH, was prepared by the reaction of Boc-His (Nτ-Boc)-OMe with 2-adamantyloxymethyl chloride (2-Adom-Cl), followed by saponification. The 2-Adom group was stable to trifluoroacetic acid (TFA), 1 N NaOH and 20% piperidine/DMF and easily removed by 1 M trifluoromethanesulfonic acid-thioanisole/TFA and HF. This new protecting group suppressed recemization during peptide synthesis and exhibited high solubility in organic solvents. It was applied to the synthesis of thyrotropin-releasing hormone (TRH) using both solution and solid-phase methods. The Nπ-2-Adom group can be used for peptide synthesis in combination with the tert-butyloxycarbonyl group as the Nd-protecting group in both solution and solid-phase methods.View full abstractDownload PDF (839K) -
Omar CHERKAOUI, Pascal NEBOIS, Houda FILLION1997 Volume 45 Issue 3 Pages 457-458
Published: March 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSMaturinone was efficiently prepared by means of a regiocontrolled Diels-Alder reaction between 5-bromo-2-ethoxycarbonyl-3-methylbenzo[b]furan-4, 7-dione 8 and penta-1, 3-diene.View full abstractDownload PDF (463K) -
Yoshiji TAKEMOTO, Taiichi OHRA, Yasuhiro YONETOKU, Chuzo IWATA1997 Volume 45 Issue 3 Pages 459-463
Published: March 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWe investigated the stereoselective construction of the C2 stereogenic center of the spiro[4.5]decane skeleton present in the spirovetivanes, spirolaurane, and spiroaxanes, and succeeded in synthesizing 2α- and 2β-substituted 6-spiro[4.5]decanones with diastereoselectivity by employing n-Bu3-SnH-mediated spiroannulation of the alkylmercury chloride, and Pd(II)-mediated spiroannulation followed by catalytic hydrogenation of the resulting unsaturated ester, respectively.View full abstractDownload PDF (814K) -
Masayuki YOSHIKAWA, Hiromi SHIMADA, Masami SAKA, Satoshi YOSHIZUMI, Jo ...1997 Volume 45 Issue 3 Pages 464-469
Published: March 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThree new ionone glucosides named corchoionosides A, B, and C were isolated from the leaves of Corhorus olitorius, commonly called "moroheiya" in Japanese, together with seven known compounds, an ionone glucoside (6S, 9R)-roseoside, a monoterpene glucoside betulalbuside A, two flavonol glucosides astragalin and isoquercitrin, two coumarin glucosides scopolin and cichoriine, and chlorogenic acid. The absolute stereostructures of corchoionosides A, B, and C were determined by chemical and physicochemical evidence, which included the result of application of a modified Mosher's method, the CD helicity rule, and chemical correlation with (6S, 9R)-roseoside. Corchoionosides A and B and (6S, 9R)-roseoside were found to inhibit the histamine release from rat peritoneal exudate cells induced by antigen-antibody reaction.View full abstractDownload PDF (945K) -
Noriaki KASHIWABA, Shigeo MOROOKA, Michiko KIMURA, Yoshie MURAKOSHI, M ...1997 Volume 45 Issue 3 Pages 470-475
Published: March 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFull details of the isolation and characterization of 52 alkaloids obtained from the tubers of Stephania cepharantha HAYATA (Menispermaceae) cultivated in Japan are presented, along with the structural determination of a new bisbenzylisoquinoline alkaloid, 3, 4-dehydrocycleanine (8).View full abstractDownload PDF (710K) -
Rong XU, Mei-Lin GO1997 Volume 45 Issue 3 Pages 476-481
Published: March 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe hydrolysis of a series of antimuscarinic tropinyl and N-methylpiperidinyl esters was investigated in 70% dimethyl sulfoxide (DMSO) (0.1 M NaOH) at 25°C. The hydrolysis followed pseudo-first order kinetics and the piperidinyl esters were hydrolyzed more rapidly than their tropinyl counterparts. Variation in the acyl (R-CO) moiety of the esters generally affected the hydrolysis of piperidinyl and tropinyl esters in a similar manner, but the orientation of the acyl moiety (axial or equatorial) did not influence the hydrolysis rate. The influence of hydrophobic, electronic and steric factors on the hydrolysis was investigated by using appropriate parameters to represent the hydrophobicity (log kw), size (molecular volume MV) and electronic character (Taft's polar substituent constant σ* and 13C chemical shift difference Δσ of R) of the esters. These were correlated to the rate constants of hydrolysis (pK1) by a series of regression equations. It was found that the hydrophobic character of the esters could account for 64% of the observed variation in pK1. However, a combination of σ* and molecular volume improved the correlation significantly, with r=0.94. The regression equation showed that an increase in the electron-withdrawing character of the acyl group R and a decrease in molecular volume of the ester favored hydrolysis.View full abstractDownload PDF (838K) -
Minoru OKADA, Toru YODEN, Eiji KAWAMINAMI, Yoshiaki SHIMADA, Masafumi ...1997 Volume 45 Issue 3 Pages 482-486
Published: March 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA series of [(4-bromobenzyl)(4-cyanophenyl)amino]azoles and their azine analogs, which have the side chain of the selective aromatase inhibitor YM511, were synthesized and evaluated for aromatase-inhibitory activity (in vivo) and for pregnant mare serum gonadotropin (PMSG)-induced estrogen synthesis inhibitory activity (in vitro). Among these aza-heterocycles, the pyrimidin-5-yl derivative (6a) was the most potent aromatase inhibitor and its in vitro inhibitory activity was comparable to that of YM511. Compound 6a also showed weak inhibitory activity on aldosterone synthesis. These data indicated that the pyrimidin-5-yl moiety is useful as a new azole fragment in place of the 4H-1, 2, 4-triazol-4-yl moiety of the aromatase inhibitor YM511.View full abstractDownload PDF (649K) -
Akio HASHIMOTO, Takashi NAKAMURA, Yoshio KOKUSENYA, Hideo NAKAI, Tadas ...1997 Volume 45 Issue 3 Pages 487-491
Published: March 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAn analytical method for determining the contents of 7 nucleic acid bases, 6 ribonucleosides and 5 deoxyribonucleosides in animal crude drugs were established. The contents in free nucleic acid components (the ice-cold extracts) and in total nucleic acid components (the heated extracts) of 8 crude drugs were quite different from one another, indicating that these content pattrens could be used as a "signal" of each animal crude drug. For example, the contents of inosine in Lumbricus, uracil in Cervi Parvum Cornu, and guanine and hypoxanthine in Hippocampus were high. The total contents in each crude drug were about twice or three times as large as the free contents. The main degradation products by the heated extracts were adenine and guanine.These results suggested that the contents of nucleic acid components could be one of the "signal" constituents for evaluation of animal crude drugs.View full abstractDownload PDF (746K) -
Effect of the Basidiomycete Poria cocos on Experimental Dermatitis and Other Inflammatory ConditionsMaria Jesus CUELLAR, Rosa Maria GINER, Maria del Carmen RECIO, Maria J ...1997 Volume 45 Issue 3 Pages 492-494
Published: March 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe hydroalcoholic extract from P. cocos was examined for oral and topical anti-inflammatory activities. It proved to be active against carrageenan, arachidonic acid, tetradecanoyl phorbol acetate (TPA) acute edemas, TPA chronic inflammation and oxazolone delayed hypersensitivity in mice. Two lanostane-type triterpenes were isolated and identified by spectroscopic methods as dehydrotumulosic and pachymic acids. Their ID50 on acute TPA edema was 4.7×10-3 and 6.8×10-4 μmol/ear, respectively.View full abstractDownload PDF (616K) -
Yu-Ming CHI, Fumio HASHIMOTO, Wen-Mei YAN, Toshihiro NOHARA, Masami YA ...1997 Volume 45 Issue 3 Pages 495-498
Published: March 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe absolute configuration of incarvilline (1), an important core compound of a number of alkaloids isolated from Incarvillea sinensis LAM., has been determined by the application of Mosher's method and X-ray crystallographic analysis of incarvilline methiodide (1a). Furthermore, the structure of hydroxyincarvilline (2) was also determined by spectroscopic means.View full abstractDownload PDF (519K) -
Tomonori NAKAMURA, Emi OKUYAMA, Atsushi TSUKADA, Mikio YAMAZAKI, Motoy ...1997 Volume 45 Issue 3 Pages 499-504
Published: March 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSActeoside (verbascoside) was isolated as an analgesic principle from Cedron (leaves and stem of Lippia triphylla (L'HER) O. KUNTZE; Verbenaceae), a Peruvian medicinal plant, by activity-guided separation. The compound exhibited analgesia on acetic acid-induced writhing and on tail pressure pain in mice by the oral administration of 300 mg/kg and 100 mg/kg, respectively. Acteoside also caused weak sedation by its effect on the prolongation of pentobarbital-induced anesthesia and on the depression of locomotion enhanced by methamphetamine. An intravenous injection of acteoside reduced the effective dose to 2 mg/kg by the writhing method. Thirteen related compounds were tested for the activity by intravenous and oral administration to obtain information on the active structure.View full abstractDownload PDF (932K) -
Makio SHIBANO, Satoshi KITAGAWA, Genjiro KUSANO1997 Volume 45 Issue 3 Pages 505-508
Published: March 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo new pyrrolidine alkaloids called broussonetines C and D were isolated from the branch of Broussonetia kazinoki SIEB. (Moraceae). Broussonetines C and D were formulated as (2R, 3R, 4R, 5R)-2-hydroxymethyl-3, 4-dihydroxy-5-(10-oxo-hydroxytridecyl)pyrrolidine (1) and (2R, 3R, 4R, 5R)-2-hydroxymethyl-3, 4-dihydroxy-5-(9-oxo-13-hydroxytridecyl)pyrrolidine (2), respectively, by spectroscopic and chemical methods. 1 and 2 showed an inhibition to β-galactosidase and β-mannosidase.View full abstractDownload PDF (615K) -
Chun-Ren CHEN, Yaw-Hung LIN, Shu-Ling CHO, Shu-Yang YEN, Hsueh-Ling S. ...1997 Volume 45 Issue 3 Pages 509-512
Published: March 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThis study used acetaminophen as a model drug and investigated the effect of soluble excipients and super disintegrants on the dissolution difference between acidic and neutral media. Tablets with various formulas were prepared and their disintegration and dissolution in both acidic and neutral media were studied. A formula containing acetaminophen and crospovidone (Polyplasdone XL), with or without sucrose, did not show a big dissolution difference between acidic and neutral media, which correlates well with the disintegration study. In contrast, a formula containing acetaminophen, sucrose and croscarmellose sodium (Ac-Di-Sol) caused longer disintegration and slower dissolution in the acidic medium than those in the neutral medium. The difference of disintegration and dissolution in both media might be due to the interaction among ingredients.View full abstractDownload PDF (681K) -
Takahiro UCHIDA, Kazushi YOSHIDA, Yoichi NAKADA, Noriko NAGAREYA, Yuri ...1997 Volume 45 Issue 3 Pages 513-517
Published: March 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSPolylactic acid (PLA) microspheres containing water-soluble anesthetics (phenobarbital sodium, pentobarbital sodium, procaine hydrochloride, lidocaine hydrochloride, or dibucaine hydrochloride) with low molecular weight were prepared using a water-in-oil-in-water (w/o/w) emulsion solvent evaporation method, and the optimization of preparative conditions was performed. In the microencapsulation of sodium salt anesthetics (phenobarbital sodium, pentobarbital sodium) into PLA matrix, the addition of NaCl (10% (w/v)) into the external aqueous phase and the choice of comparatively high concentration of PLA (16% (w/v)) in CH2Cl2 significantly improved drug loading efficiency compared to the case when no additives were added to the external aqueous phase, or low PLA concentration (4% (w/v)) in CH2Cl2 was employed in the manufacturing process. The loading efficiency of hydrochloride salt anesthetics (procaine hydrochloride, lidocaine hydrochloride, or dibucaine hydrochloride) in PLA microspheres, in constract, was dramatically improved using the alkalic buffer solution as the external aqueous phase. The mean volume diameter was obtained in the region of 20-30 μm and normal distribution for prepared microspheres in all cases. PLA microspheres containing 10% (theoretical) of various anesthetics exhibited so-called burst releases, but, some portion of the loaded anesthetics still remained in the microspheres at 7 d.View full abstractDownload PDF (822K) -
Toru MAEJIMA, Takashi OSAWA, Kingo NAKAJIMA, Masao KOBAYASHI1997 Volume 45 Issue 3 Pages 518-524
Published: March 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new method, the tumbling melt granulation (TMG) method, for preparing spherical beads without any use of solvents, was developed. A powdered mixture of meltable materials and non-meltable materials was fed gradually and successively onto the seed materials, which were blown with hot slit air using a centrifugal fluidizing bed granulator. As a consequence, the mixture adhered to the seed materials to spontaneously from the spherical beads. First, the effects of several factors concerned with granulatability were investigated using nonpareil as the seed materials; lactose as the non-meltable material; and polyethylene glycol, hydrogenated rape oil, and fatty acids as meltable material. In order to prepare spherical beads with a narrow particle size distribution and a smooth surface, it was concluded from this series of experiments that the bed temperature during the processing should be maintained at least 5°C higher than the melting point of the meltable material; particle sizes of both the meltable and the non-meltable materials should be lowered below one-sixth of the diameter of the seed materials; and the mixing ratio of the meltable material in the powdered mixture should be set at an optimum value. Then, the TMG method was applied to several kinds of drugs with various physicochemical properties. It was revealed that this method was very useful and widely applicable since even bisbentiamine, with which it was difficult to prepare spherical beads by the wet powder coating method, could be granulated easily by this new method. Further, it was shown that this method could be applied successfully to seed materials whose shape was non-spherical, such as cube-shaped sucrose crystals.View full abstractDownload PDF (1064K) -
Keiichi TOKIHIRO, Tetsumi IRIE, Kaneto UEKAMA1997 Volume 45 Issue 3 Pages 525-531
Published: March 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSMaltosyl-β-cyclodextrin (G2-β-CyD) suppressed the aggregation of insulin in neutral solution, while the sulfate of β-CyD (S-β-CyD) accelerated the aggregation. On the other hand, the sulfobutyl ether of β-CyD (SBE-β-CyD) showed varying effects on insulin aggregation, depending on the degree of substitution of the sulfobutyl group : i.e., the inhibition at relatively low substitution and acceleration at higher substitution. Differential scanning calorimetric studies indicate that the self-association of insulin stabilized the native conformation of the peptide, as indicated by an increase in the mean unfolding temperature (Tm). G2-β-CyD and SBE-β-CyD decreased the Tm value of insulin oligomers, while S-β-CyD increased the Tm value. 1H-Nuclear magnetic resonance spectroscopic studies suggest that G2-β-CyD includes accessible hydrophobic side chains of insulin within the CyD cavity, and hence perturbs the intermolecular hydrophobic contacts between aromatic side chains across the monomer-monomer interfaces. By contrast, the electrostatic interaction between the positive charges of insulin and the concentrated negative charges of the sulfate and sulfonate groups of a the anionic β-CyDs seems to be more of factor than the inclusion effects. These results suggest proper use of the CyD derivatives could be effective in designing rapid or long-acting insulin preparations.View full abstractDownload PDF (1036K) -
Tomohiro ENDO, Hiromasa NAGASE, Haruhisa UEDA, Shoichi KOBAYASHI, Tsun ...1997 Volume 45 Issue 3 Pages 532-536
Published: March 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSCyclomaltodecaose (ε-cyclodextrin, ε-CD), cyclomaltoundecaose (ζ-CD) and cyclomaltotridecaose (θ-CD) are a series of cyclomalto-oligosaccharides composed of ten, eleven and thirteen α-(1→4)-linked D-glucopyranose units, respectively. ε-CD, ζ-CD and θ-CD were purified from the commercially available CD powder mainly using the combined treatment of HPLC and column chromatographies. The molecular weights of ε-CD, ζ-CD and θ-CD were determined by FAB-MS, and their cyclic structures were identified by 1H-NMR and 13C-NMR. Furthermore, the 13C-NMR chemical shift of large-ring cyclodextrins composed of several α-(1→4)-linked D-glucopyranose units, in which numbers 9, 10, 11, 12, and 13 are named δ-, ε-, ζ-, η-, θ-CD, were elucidated and compared with those of conventional α-, β-, and γ-CD.View full abstractDownload PDF (612K) -
Yukiya YAMAGUCHI, Tsutomu USAMI, Hideshi NATSUME, Takao AOYAGI, Yu NAG ...1997 Volume 45 Issue 3 Pages 537-541
Published: March 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFour polymeric membranes were prepared consisting of various ratios of 2-hydroxyethyl-methacrylate/polydimethylsiloxane-methacrylate copolymer. These membranes had both lipophilic and hydrophilic domains in their copolymer networks like skin barrier. From permeation studies of the aqueous solutions or suspensions of various lipophilic and hydrophilic drugs using these membranes, a membrane having a similar drug permeability to hairless rat and human skins was selected. Permeation of indomethacin through the selected polymer membrane from simple ointment, gel and a marketed cream were then measured. About 102 times higher permeability was found in the polymer membrane than through excised hairless rat skin, but the rank order of the permeability through the polymer membrane among the formulations was the same through the skin membranes. These higher permeations of indomethacin were probably related to physical and chemical properties of pharmaceutical additives in the topical formulations. It is concluded that these synthetic polymer membranes may be utilized as an alternative tool to predict human or rat skin permeability of various (hydrophilic or lipophilic) drugs as well as to screen drug candidates for transdermal drug delivery.View full abstractDownload PDF (793K) -
Kosaku HIROTA, Keiko KUBO, Hironao SAJIKI1997 Volume 45 Issue 3 Pages 542-544
Published: March 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe reaction of the 5-thioformyluracil 1 with phenylhydrazine and various amines readily afforded the hydrazone 3a and Schiff bases 3b-d, respectively. Further, carbanions and Wittig reagents reacted with 1 to give pyrido[2, 3-d]pyrimidines 4 and 9. The corresponding 5-formyluracil 2 possessed much lower reactivities toward these nucleophiles than did 1.View full abstractDownload PDF (612K) -
Noriaki KASHIWABA, Shigeo MOROOKA, Minoru ONO, Jun TODA, Hideki SUZUKI ...1997 Volume 45 Issue 3 Pages 545-548
Published: March 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFrom the leaves of Stephania cepharantha HAYATA (Menispermaceae) cultivated in Japan, a new morphinane alkaloid, cephasugine (1), was isolated together with 14 known alkaloids. The structure of 1 was elucidated as the N-methyl derivative of sinococuline (17) by comparison of spectroscopic data with those of cephakicine (16). This is the first report of the alkaloidal constituents of the leaves of S. cepharantha.View full abstractDownload PDF (470K) -
Masazumi IKEDA, Kazumi MARUYAMA, Youichi NOBUHARA, Toshihiro YAMADA, S ...1997 Volume 45 Issue 3 Pages 549-551
Published: March 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSBis(1H-pyrazol-1-yl)- and bis(1H-imidazol-1-yl)pyrimidines were synthesized and evaluated for cytoprotective effects. Among them, 4, 6-bis(1H-pyrazol-1-yl)pyrimidine (3) showed a potent inhibitory effect on the HCl·ethanol-, ethanol-, and water immersion stress-induced gastric lesions in rats, and a very low acute toxicity. One of the major factors reponsible for the cytoprotective effects of 3 is the increase in the bicarbonate secretion. This compound appears to be a promising cytoprotective drug for the treatment of gastric mucosal ulcers.View full abstractDownload PDF (655K) -
Motoh MUTSUGA, Keisuke KOJIMA, Iclal SARACOGLU, Yukio OGIHARA1997 Volume 45 Issue 3 Pages 552-554
Published: March 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFour new minor saponins, papyrioside LE-LH, were isolated from the leaves of Tetrapanax papyriferum, and their structures were determined on the basis of spectroscopic evidence.View full abstractDownload PDF (487K) -
Achmad SYAHRANI, Gunawan INDRAYANTO, SUTARJADI, Alistair WILKINS1997 Volume 45 Issue 3 Pages 555-557
Published: March 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new conversion product, salicylamide 2-O-β-D-glucopyranoside was isolated from cell suspension cultures of Solanum mammosum following the administration of salicylamide. The time-course of the bioconversion was monitored in these suspension cultures.View full abstractDownload PDF (488K) -
Yoshihiro MIMAKI, Minpei KURODA, Osamu NAKAMURA, Yutaka SASHIDA, Tadaa ...1997 Volume 45 Issue 3 Pages 558-560
Published: March 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSNew polyhydroxylated steroidal saponins (1, 2) were isolated from the tubers of Brodiaea californica. The structures were determined by spectroscopic analysis and acid-catalyzed hydrolysis. The bisdesmosidic saponin (2) is unique in structure, and is the first representative of a steroidal saponin bearing 6-deoxy-D-gulopyranose among both the steroidal and triterpene saponins reported up to the present.View full abstractDownload PDF (496K) -
Masayuki YOSHIKAWA, Toshiyuki MURAKAMI, Masahiro INADUKI, Kazuhiro HIR ...1997 Volume 45 Issue 3 Pages 561-563
Published: March 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe absolute stereostructures of betavulgarosides III and IV, which were isolated from the roots of Beta vulgaris L. (sugar beet) and exhibited inhibitory activity on glucose absorption, were determined by the chemical correlation of betavulgaroside IV with a known saponin momordin I, which included the conversion from the α-L-arabinopyranosyl moiety of momordin I to the acidic acetal-type substituent of betavulgarosides III and IV via the α-L-ribopyranosyl derivative. Furthermore, four acidic acetal-type substituent analogues were synthesized from L- and D-arabinose.View full abstractDownload PDF (490K) -
Rena KASIMU, Purusotam BASNET, Yasuhiro TEZUKA, Shigetoshi KADOTA, Tsu ...1997 Volume 45 Issue 3 Pages 564-566
Published: March 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo new abietane-type diterpenoids, danshenols A (1) and B (2), were isolated from an MeOH extract of Salvia miltiorhiza BUNGE, and their structures determined by chemical and spectroscopic methods including the 2D NMR technique. Danshenol A (1) showed strong inhibitory activity against aldose reductase isolated from the eye lens of rats.View full abstractDownload PDF (477K) -
Koji HASE, Shigetoshi KADOTA, Purusotam BASNET, Jianxin LI, Shuichi TA ...1997 Volume 45 Issue 3 Pages 567-569
Published: March 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTetrahydroswertianolin (1), a new tetrahydroxanthone glycoside, was isolated from the whole plant of Swertia, MAKINO (Gentianaceae). Its structure was determined by chemical and spectroscopic methods including 2D-NMR. This compound was found to be very effective in immunologically induced liver injury in mice.View full abstractDownload PDF (472K) -
Masayuki YOSHIKAWA, Toshiyuki MURAKAMI, Nobuhiro YAGI, Nobutoshi MURAK ...1997 Volume 45 Issue 3 Pages 570-572
Published: March 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIndirect anodic oxidation of soyasapogenol B (3β, 22β, 24-trihydroxyolean-12-ene) was carried out using KI as a mediator in t-BuOH-H2O solution, so that the 3-ketone derivative was obtained as the only oxidation product in a favorable yield. As a result of application to various polyhydroxylated triterpenes, selective electrochemical oxidation was shown to occur in the C-3 hydroxyl group of the polyhydroxyl triterpenes with the C-24 hydroxyl group. The reaction pathway is discussed.View full abstractDownload PDF (491K) -
Akiko ITAI, Atsushi MATSUO, Miho Y. MIZUTANI, Nobuo TOMIOKA, Mayuko T. ...1997 Volume 45 Issue 3 Pages 573-575
Published: March 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWe simulated the docking of two teleocidin congeners to the cys2 domain structure observed in the crystalline complex of protein kinase Cδ with phorbol-13-acetate. The most stable docking models were searched for two conformers of (-)-indolactam-V ((-)-IL-V), twist and sofa form, and for (-)-benzolactam-V ((-)-BL-V8) by using an automatic docking method, ADAM, which can cover all possible binding modes and conformations. The twist form of (-)-IL-V and (-)-BL-V8 molecules fitted well into the same cavity as phorbol-13-acetate. Of the three functional groups hydrogen-bonding to the protein, two hydrogen-bonded with protein atoms in common with phorbol-13-acetate, but the third one hydrogen-bonded with a different protein atom from that in the case of phorbol-13-acetate.View full abstractDownload PDF (528K)
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