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Volume 48, Issue 11
Displaying 1-50 of 53 articles from this issue
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Viqar Uddin AHMAD, Akbar ALI, Zulfiqar ALI, Farah Naz ZAFAR, Muhammad ...2000 Volume 48 Issue 11 Pages 1597-1601
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo novel bidesmosidic cycloartane-type glycosides, depressosides C and D were isolated from Corchorus depressus L. Their structures were elucidated as (22R)-16β, 22-epoxy-3β, 26-dihydroxy-9, 19-cyclolanost-24E-ene 3, 26-di-O-β-D-glucopyranoside and (22R, 24S)-22, 25-epoxy-3β, 16β-24-trihydroxy-9, 19-cyclolanostane 3, 24-di-O-β-D-glucopyranoside, respectively on the basis of chemical evidence and detailed spectroscopic studies.View full abstractDownload PDF (759K) -
Kazutoyo ENDO, Ikuko SAITO, Chikako HONDA, Ken-ichiro MATSUMOTO, Yasus ...2000 Volume 48 Issue 11 Pages 1602-1605
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe α-diimine Fe2+ complexes, [Fe(phen)3]2+, [Fe(bpy)3]2+, and [Fe(terpy)2]2+, (phen : 1, 10-phenanthroline, bpy : 2, 2'-bipyridyl, terpy : α, α', α"-tripyridine) were intercalated into zirconium dihydrogenphosphate phosphate dihydrate (γ-zirconium phosphate, γ-ZrP), Zr(PO4)(H2PO4)·2H2O. The rate of the intercalation, the molar ratio of Fe to Zr, was found to be 3.82-7.76%. Mossbauer spectra indicated that one part of [Fe(phen)3]2+ and [Fe(bpy)3]2+ changed from a low-spin Fe2+ to high-spin Fe2+ state on intercalation, but [Fe(terpy)2]2+ did not change in chemical state. The lattice dynamics of the complexes and the intercalation compounds were investigated in terms of the temperature dependence of the area intensity on the Mossbauer spectra. A linear relationship was established for all the complex salts and the intercalation compounds investigated between the ln[A(T)/A(82)] and absolute temperature, T, where A(T) and A(82) show the intensities of a doublet at T and 82 K of the Mossbauer spectra, respectively. From the slope of the linear relation, the Θ2M values, which were derived based on the Debye approximation of lattice vibration, were evaluated for the complex salts and the intercalation compounds. The Fe2+ complexes showed Θ2M values of 1.27 to 2.32×106, whereas the intercalation compounds showed very similar values to each other, ranging from 2.19 to 2.39×106, irrespective of different α-diimine ligands. The results were explained in terms of the characteristics layered structure of zirconium phosphate, and by the tight bond between the α-diimine Fe2+ complexes and the host γ-ZrP.View full abstractDownload PDF (719K) -
Li-Quan WANG, Meselhy R. MESELHY, Yan LI, Guo-Wei QIN, Masao HATTORI2000 Volume 48 Issue 11 Pages 1606-1610
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSeven metabolites were isolated after anaerobic incubation of secoisolariciresinol diglucoside (1) with a human fecal suspension. They were identified as (-)-secoisolariciresinol (2), 3-demethyl-(-)-secoisolariciresinol (3), 2-(3-hydroxybenzyl)-3-(4-hydroxy-3-methoxybenzyl)butane-1, 4-diol (4), didemethylsecoisolariciresinol (5), 2-(3-hydroxybenzyl)-3-(3, 4-dihydroxybenzyl)butane-1, 4-diol (6), enterodiol (7) and enterolactone (8).Furthermore, two bacterial strains, Peptostreptococcus sp. SDG-1 and Eubacterium sp. SDG-2, responsible for the transformation of 1 to a mammalian lignan 7, where isolated from a human fecal suspension. The former transformed 2 to 3 and 5, as well as 4 to 6, and the latter transformed 5 to 6 and 7.View full abstractDownload PDF (854K) -
Giacomina R. MANDELLI, Stefano MAIORANA, Patrizia TERNI, Giuseppina LA ...2000 Volume 48 Issue 11 Pages 1611-1622
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA series of 5H-dibenz[b, f]azepine derivatives was prepared and evaluated for binding affinities to muscarinic receptors in vitro. Among them, compound 8 showed a high affinity for human recombinant M2 receptors (Ki=2.6 nM), a low affinity for M4 receptors (39-fold less than for M2 receptors) and a very low affinity for M1 and M3 receptors (119- and 112-fold less than for M2 receptors, respectively). The high M2 selectivity of 8 may be attributed to the olefinic bond of the azepine ring. Functional experiments showed 8 to be a competitive antagonist with high affinity to the cardiac (pA2=7.1) and low affinity to the intestinal muscarinic receptors (IC50=0.54 μM). In vivo experiments confirmed the in vitro M2 selectivity of 8. Acetylcholine-induced bradycardia was dose-dependently antagonized in rats after both intravenous and intraduodenal administration of 8. In rats, cholinergic functions mediated by M1 or M3 receptors (salivary secretion, pupil diameter, gastric emptying, intestinal transit time) were not affected by the oral administration of 8 even at doses as high as 30 times the antibradycardic effective dose. Furthermore, 8 had no analgesic activity in mice, indicating poor central nervous system penetration. In dogs, nocturnal bradycardia was dose-dependently inhibited by the oral route with a duration of action of about 24 h. Compound 8 appears to be a promising cardioselective antimuscarinic agent for the treatment of dysfunctions of the cardiac conduction system such as sinus or nodal bradycardia ("sick-sinus syndrome") and atrioventricular block.View full abstractDownload PDF (1590K) -
MarcoAntonio MORENO, Paloma FRUTOS, Ma Paloma BALLESTEROS, ...2000 Volume 48 Issue 11 Pages 1623-1627
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe release of nortriptyline hydrochloride from oil-in-water (o/w) microemulsions (isopropyl myristate as oil, propylene glycol as cosurfactant, polysorbate 80 as surfactant and phosphate buffer, pH 7.4, as the continuous phase) containing increasing concentrations of polyethylene glycol 400, used to facilitate the diffusion of a drug from the inner oily phase of the microemulsion to the outer aqueous phase of such a dispersion system, was studied by determing the permeability constants of the drug through hydrophilic and lipophilic membranes separating the o/w microemulsions from the receiving aqueous phase (phosphate buffer pH 7.4). The permeability of nortriptyline hydrochloride from microemulsions through the lipophilic membrane increased as the concentration of polyethylene glycol 400 in the disperse system increased. The apparent permeability constant for nortriptyline hydrochloride, from the microemulsion without polyethylene glycol, was 1.36×10-3 cm·h-1, it increased up to 7.80×10-3 cm·h-1 in the presence of polyethylene glycol at a concentration of 50% (v/v) of the initial volume of the aqueous phase.View full abstractDownload PDF (799K) -
Hajime KATAYAMA, Yoshimitsu KIRYU, Kimiyoshi KANEKO, Rie OHSHIMA2000 Volume 48 Issue 11 Pages 1628-1633
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe structure activity relationship (SAR) in the anti-cancer activities of pyrazolo[1, 5-a]indole derivatives was investigated, and the following conclusions were obtained : 1) N(1)-quaternarization is essential for anti-cancer activity, 2) the size and polarity of the 2-substituent is crucial for in vitro activity which allows further investigation in an in vivo test, 3) the effect of the 4-substituent on the activity is minor compared with the other two factors.View full abstractDownload PDF (1106K) -
Catherine PETIT, Vania BERNARDES-GENISSON, Pascal HOFFMANN, Jean-Pierr ...2000 Volume 48 Issue 11 Pages 1634-1638
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFive novel S-nitrosothiol compounds (6-10) derived from L-cysteine were generated in solution and their decomposition rate was followed by UV spectroscopy. In acetonitrile, compounds 9 and 10 were the most stable of this series with a half-life of 24 h. The final organic decomposition products of the five S-nitrosothiols were also analysed. Derivatives 8, 9, and 10, possessing a phenolic hydroxyl group, afforded an unexpected decomposition pathway, with nitration of aromatic ring occurring in non-aqueous media. A mechanism involving a phenoxy radical seems to be implicated.View full abstractDownload PDF (903K) -
Tin Wui WONG, Lai Wah CHAN, Paul Wan Sia HENG2000 Volume 48 Issue 11 Pages 1639-1643
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSMelt pelletization of lactose 450 M was carried out in an 8-l high shear mixer using PEG 3000 as the meltable binder. The pore size and size distribution of the melt pellets were determined using mercury intrusion porosimetry. The pore size distribution of melt pellets was found to be bimodal. With a higher binder concentration, post-melt impeller speed or longer post-melt processing time, the fraction of large pores in the agglomerates was reduced but the tendency of the agglomerates to develop sub-micron pores increased. The extent of formation of large pores was dependent on the interplay between the inter-particle distance of lactose particles and the contraction property of molten binder. High process temperature was associated with a greater amount of water loss from the melt agglomerates. The water vapor liberated from the lactose particles, was trapped in the molten PEG during the pelletization process. The formation of sub-micron pores was a result of escape of this water vapor on solidification of the molten PEG as well as agglomerate densification. The quantity of sub-micron pores produced was found to be related to the level of water loss. The melt agglomeration gave rise to large agglomerates when long post-melt processing time, high post-melt impeller speed or binder concentration was used.View full abstractDownload PDF (1362K) -
Yoshiaki SHIMADA, Nobuaki TANIGUCHI, Akira MATSUHISA, Kenichiro SAKAMO ...2000 Volume 48 Issue 11 Pages 1644-1651
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA series of compounds structually related to 4'-[(4, 4-difluoro-5-methylidene-2, 3, 4, 5-tetrahydro-1H-1-benzoazepin-1-yl)carbonyl]-2-phenylbenzanilide were synthesized and evaluated for arginine vasopressin (AVP) antagonistic activity. Compounds with a (Z)-olefin geometry at the 5-position of benzoazepine possessed potent affinity for both the V1A and V2 receptors. Further study has shown that one of these derivatives, (Z)-4'-({4, 4-difluoro-5-[(4-dimethylaminopiperidino)carbonylmethylene]-2, 3, 4, 5-tetrahydro-1H-1-benzoazepin-1-yl}carbonyl)-2-phenylbenzanilide monohydrochloride (29, YM-35471), exhibits exceptionally potent affinity for both of V1Aand V2 receptors, even when administered orally. The synthesis and pharmacological properties of this compound are detailed in this paper.View full abstractDownload PDF (1242K) -
Masashi ETO, Shoji KUBOTA, Hidetoshi NAKAGAWA, Yasuyuki YOSHITAKE, Kaz ...2000 Volume 48 Issue 11 Pages 1652-1659
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe solid β-cyclodextrin (β-CyD) complex of O-cinnamyl S-methyl dithiocarbonates (xanthate, 1a), upon heating at 45°C, underwent asymmetric [3, 3]-sigmatropic rearrangement to give the optically S-(1-phenylallyl) S-methyl dithiocarbonate (2a) with 60% ee. Heating the β-CyD complex of 2a at 120°C caused extrusion of COS to give cinnamyl methyl sulfide (3a) in high yield. The reaction behavior and role of β-CyD are discussed based on molecular orbital calculation data.View full abstractDownload PDF (1069K) -
Toshiyuki HATA, Yukio ONO2000 Volume 48 Issue 11 Pages 1660-1666
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSMonte Carlo (MC) simulations were carried out for an infinitely dilute aqueous solution of two stable conformers (gGg' and tGg') and of three conformations between gGg' and tGg' conformers of ethylene glycol (EG) at 298 K. Based on the spatial distribution function (SDF) gOO(x, y, z), obtained from the MC simulation in the above conformations in liquid water, the high distribution of hydration water molecules could be divided into hydrogen acceptor (HA), hydrogen donor (HD), MIX (overlapped distribution of HA and HD), and hydrophobic hydration (HH) regions. The spatial orientations of hydrogen-bonded water molecules were found to be of a linear type with a triple-layer structure in the HA region and HA part (in the MIX region), and double-layer structures in the HD region and HD part (in the MIX region). In addition, it was apparent that the spatial orientations of these water molecules were of the linear type throughout the conformational change process from gGg' to tGg' conformers in liquid water. From the difference SDF (DSDF), ΔgOO(x, y, z), between the SDFs of two conformations, we concluded that the distribution of hydration water molecules in the HA and HD parts of the MIX region are governed by the competition of internal hydrogen bonds between the hydrogen atom and two lone-pair electrons on the oxygen atom of an EG molecule.View full abstractDownload PDF (1344K) -
Katsuhiro KAWAKAMI, Hisashi TAKAHASHI, Hitoshi OHKI, Kenichi KIMURA, S ...2000 Volume 48 Issue 11 Pages 1667-1672
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA series of 8-methoxyquinolones bearing 3-amino-4-methylpyrrolidines or 3-amino-4-fluoromethylpyrrolidines at the C-7 position was synthesized and their physicochemical and biological properties were evaluated. All of the compounds synthesized showed more potent activity than LVFX (3) against both gram-positive and - negative bacteria. Increases in lipophilicity of these compounds had desirable effects on their potency of single intravenous toxicity and pharmacokinetic profiles in animals. Among the compounds synthesized, 1-fluorocyclopropyl derivatives 17 and 20, and 7-(cis-3-amino-4-fluoromethylpyrrolidinyl) derivative 19 (DC-756h) showed negative responses in the micronucleus test in mice while 1-cyclopropyl-7-(3-aminopyrrolidinyl) derivative 16 showed a positive response. These results suggested that the introduction of a fluorine atom into the 3-aminopyrrolidinyl substituent resulted in favorable influence on genetic toxicity as well as into the N-1 cyclopropyl substituent.View full abstractDownload PDF (958K) -
Toshiyuki MURAKAMI, Kentarou KOHNO, Akinobu KISHI, Hisashi MATSUDA, Ma ...2000 Volume 48 Issue 11 Pages 1673-1680
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new ent-kaurane-type glycoside, canavalioside, and eight new acylated flavonol glycosides, gladiatosides A1, A2, A3, B1, B2, B3, C1 and C2, were isolated from the seed of Canavalia gladiata together with robinin, kaempferol 3-O-β-D-galactopyranosyl-7-O-α-L-rhamnopyranoside, and kaikasaponin III. The absolute stereostructures of canavalioside and gladiatosides A1, A2, A3, B1, B2, B3, C1 and C2 were elucidated on the basis of chemical and physicochemical evidence.View full abstractDownload PDF (1200K) -
Chao-mei MA, Norio NAKAMURA, Masao HATTORI2000 Volume 48 Issue 11 Pages 1681-1688
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSOleanolic acid derivatives with different lengths of 3-O-acidic acyl chains were synthesized and evaluated for their inhibitory activity against HIV-1 protease. The lengths of the acidic chains were optimized to 6 and 8 carbons. Changing a 3-ester bond to an amide bond or dimerization of the triterpenes retained their inhibitory activity against HIV-1 protease. Introduction of an additional acidic chain to C-28 of oleanolic acid increased the inhibitory activity appreciably, though a derivative with only one acidic chain linked at C-28 also showed potent activity against HIV-1 protase.The inhibitory mechanism was proved directly by size exclusion chromatography to be inhibition of dimerization of the enzyme polypeptides. The ester bonds of the triterpene derivatives were found to be stable to lipase under mild alkaline conditons.View full abstractDownload PDF (1215K) -
Susumu IGARASHI, Hiroshi INAMI, Hiromu HARA, Hiroshi KOUTOKU, Hiroyuki ...2000 Volume 48 Issue 11 Pages 1689-1697
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWhile searching for novel nonsteroidal inhibitors of human and rat prostatic 5α-reductases, we found a new series of indoline and aniline derivatives that showed potent inhibitory activities for both enzymes. Among them, 3-chloro-4-{1-(4-phenoxybenzyl)indolin-5-yl]oxy}benzoic acid (2e, YM-36117) showed a more portent inhibitory activity for the human enzyme than ONO-3805 with an IC50 value of 5.3 nM and a reduced rat prostatic dihydrotestosterone (DHT) concentration by oral administration. The synthesis and the structure-activity relationships of these indoline and aniline derivatives are presented.View full abstractDownload PDF (1197K) -
Shuji KITAGAWA, Masatoshi KASAMAKI, Ai IKARASHI2000 Volume 48 Issue 11 Pages 1698-1701
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSEffects of cetyltrimethylammonium and two other n-alkyltrimethylammoniums on the permeation of benzoic acid through excised guinea pig dorsal skin were examined. Cetyltrimethylammonium markedly increased both the flux and permeability coefficient in the concentration range of 0.5 and 5 mM. However, 50 mM cetyltrimethylammonium decreased them. The presence of 2 mM cetyltrimethylammonium, which induced a maximal enhancement effect, also increased the fluxes of 4-methyl, 4-ethyl and 4-n-propyl substituents of benzoic acid, but the enhancement effects were less. Analysis of the free energy of transfer of the methylene group of the substituents from the aqueous phase to skin suggested that cetyltrimethylammonium made the skin relatively more hydrophilic. Electron spin resonance spectra analysis by a long-chain quanternary alkylammonium analog, 4-(N, N-dimethyl-N-pentadecyl)ammonium-2, 2, 6, 6-tetramethylpiperidine-1-oxyl iodide (CAT-15), showed that the spin label was present in a nearly solid state in both excised skin and its stratum cornuem. This finding suggested the high affinity of the long-chain alkylammoniums to proteins in the stratum corneum and the involvement of the intraction between the cationic surfactants and the proteins in their improvement of the hydrophilic property of the skin, as well as their marked enhancement effects on the skin permeation of relatively hydrophilic drugs.View full abstractDownload PDF (693K) -
Haruko TAKECHI, Yoshiyuki ODA, Naozumi NISHIZONO, Kazuaki ODA, Minoru ...2000 Volume 48 Issue 11 Pages 1702-1710
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIn order to find a highly sensitive fluorophore, 3-azolyl-7-diethylaminocoumarin derivatives were synthesized. Both the absorption and fluorescence maxima of the coumarin-thiazole compounds showed red shifts with increases of the molar absorptivities and fluorescence intensities, in comparison with those of the corresponding coumarin-oxazole compounds. Among them, 3-(5-ethoxycarbonyl-1, 3-thiazol-2-yl)-7-diethylamino-2H-chromen-2-one (3e) was one of the most promising candidates as a fluorophore accessible for analytical purposes in the fields of analytical and biological chemistry.View full abstractDownload PDF (1217K) -
Yasuhiro TEZUKA, Pavlos STAMPOULIS, Arjun H. BANSKOTA, Suresh AWALE, K ...2000 Volume 48 Issue 11 Pages 1711-1719
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFrom the MeOH extract of the aerial part of Vietnamese Orthosiphon stamineus, five new isopimarane-type diterpenes [orthosiphols F-J (1-5)] and two new diterpenes [staminols A (6) and B (7)] with a novel carbon-framework, to which we proposed the name "staminane", and three new highly-oxygenated staminane-type diterpenes [staminolactones A (8) and B (9) and norstaminol A (10)] were isolated. Moreover, staminolactone A (8) is 8, 14-secostaminane-type and staminolactone B (9) is 13, 14-secostaminane-type, while norstaminol A (10) is 14-norstaminen-type. Together with these new diterpenes, sixteen known compounds were also isolated and identified to be : 7, 3', 4'-tri-O-methylluteolin (11), eupatorin (12), sinensetin (13), 5-hydroxy-6, 7, 3'4'-tetramethoxyflavone (14), salvigenin (15), ladanein (16), tetramethylscutellarein (17), 6-hydroxy-5, 7, 4'-trimethoxyflavone (18), vomifoliol (19), aurantiamide acetate (20), rosmarinic acid (21), caffeic acid (22), oleanolic acid (23), ursolic acid (24), betulinic acid (25), and β-sitosterol (26). All the isolated compounds were tested for their cytotoxicity towards highly liver metastatic murine colon 26-L5 carcinoma cells, and the new diterpenes, except for 4, and flavonoids (11, 12, 16, 18) showed cytotoxicity with an ED^<50> value between 10 and 90 μg/ml.View full abstractDownload PDF (1175K) -
Toshiyuki MURAKAMI, Junko NAKAMURA, Tadashi KAGEURA, Hisashi MATSUDA, ...2000 Volume 48 Issue 11 Pages 1720-1725
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFollowing the investigation of assamsaponins A, B, C, D, and E, four new saponins termed assamsaponins F, G, H, and I were isolated from the seeds of the tea plant (Cammellia sinensis L. var. assamica PIERRE), while assamsaponin J was isolated from its leaves. The structures of assamsaponins F-J were elucidated on the basis of chemical and physicochemical evidence and found to be 16, 22-O-diacetyl-21-O-angeloyltheasapogenol E 3-O-[β-D-galactopyranosyl(1→2)][β-D-glucopyranosyl(1→2)-α-L-arabinopyranosyl(1→3)]-β-D-glucopyranosiduronic acid, 21-O-angeloyl-22-O-acetyltheasapogenol E 3-O-[β-D-galactopyranosyl(1→2)][β-D-glucopyranosyl(1→2)-α-L-arabinopyranosyl(1→3)]-β-D-glucopyranosiduronic acid, 21-O-angeloyl-28-O-acetyltheasapogenol E 3-O-[β-D-galactopyranosyl(1→2)][β-D-glucopyranosyl(1→2)-α-L-arabinopyranosyl(1→3)]-β-D-glucopyranosiduronic acid, 21-O-tigloyl-28-O-acetyltheasapogenol E 3-O-[β-D-galactopyranosyl(1→2)][β-D-glucopyranosyl(1→2)-α-L-arabinopyranosyl(1→3)]-β-D-glucopyranosiduronic acid, and 16, 21-O-biacetyl-22-O-cinnamoyltheasapogenol B 3-O-[β-D-galactopyranosyl(1→2)][β-D-rhamnopyranosyl(1→2)-α-L-arabinopyranosyl(1→3)-β-D-glucopyranosiduronic acid, respectively.The saponin mixture from the seeds of the tea plant was found to exhibit an inhibitory effect no gastric emptying and an accelerating effect on gastrointestinal transit in mice. Theasaponin E1, the principle saponin of the tea plant, showed potent activity, while theasaponin E2 showed none, so that the position of the acyl groups in the sapogenin moiety is important from a pharmacological point of view.View full abstractDownload PDF (1034K) -
Lia Dewi JULIAWATY, Mariko KITAJIMA, Hiromitsu TAKAYAMA, Sjamsul Arifi ...2000 Volume 48 Issue 11 Pages 1726-1728
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new type of natural product, idenburgene (1), was isolated from Crytocarya idenburgensis, and its unique structure was elucidated. Four known compounds, 3-hydroxy-5-methoxystilbene (2), 2', 6'-dihydroxy-4'-methoxy-dihydrochalcone (3), stigmast-4-ene-3-one, and β-sitosterol were also isolated and identified.View full abstractDownload PDF (538K) -
[2-(ω-Phenylalkyl)phenoxy]alkylamines III : Synthesis and Selective Serotonin-2 Receptor Binding (2)Naoki TANAKA, Riki GOTO, Rie ITO, Miho HAYAKAWA, Atsuhiro SUGIDACHI, T ...2000 Volume 48 Issue 11 Pages 1729-1739
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA series of [2-(2-phenylethyl)phenoxy]ethylpyrrolidine derivatives were synthesized, and their affinity for serotonin-2 (5-HT2) and dopamine-2 (D2) receptors was examiend. Among them, compound 17, (2R, 4R)-4-hydroxy-2-[2-[2-[2-(3-methoxyphenyl)ethyl]phenoxy]ehtyl]-1-methylpyrrolidine hydrochloride. showed high 5-HT2 receptor affinity in vitro. This compound was a more potent inhibitor of ex vivo 5-HT-induced platelet aggregation than compound 3, which was previously shown to be more potent than ketanserin (1) and sarpogrelate (2a). However, compound 17 produced gastric irritaiton in rats. Therefore, we carried out a further derivatization of 17, and compound 45 (R-102444), a lauryl ester prodrug of compound 17, was found to be a promising candidate as an antithrombotic agent. Oral administration of R-102444 produced a marked inhibition of 5-HT-induced ex vivo platelet aggregation, and R-102444 did not cause any gastric irritation. The antiaggregatory effects of R-102444 were more potent than those of sarpogrelate (2a) and its active metabolite, M-1 (2b). In addition, R-102444 exhibited more potent antithrombotic effects than sarpogrelate in a rat photochemically-induced thrombosis model.View full abstractDownload PDF (1692K) -
Keiko HOJO, Mitsuko MAEDA, Shin IGUCHI, Timothy SMITH, Hiroshi OKAMOTO ...2000 Volume 48 Issue 11 Pages 1740-1744
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSp-Nitroanilides of amino acids and peptides are widely used as the chromogenic substrates for the determination of the activity of proteolytic enzymes. However, the preparation of a p-nitroanilide is not easy, in part due to the low nucleophilicity of the amino group of p-nitroaniline. A facile preparation of p-nitroanilide analog by the solid-phase method was investigated. 5-Amino-2-nitrobenzoic acid (Anb5, 2) was used instead of p-nitroaniline (pNA) for preparation of p-nitroanilide analogs. Anb5, 2 was introduced on a p-methylbenzhydrylamine resin without protection of the amino group of Anb5, 2 by the 2-(H-benzotriazol-1-yl)-1, 1, 3, 3-tetramethyluronium tetrafluoroborate (TBTU) method in the presence of p-dimethylaminopyridine. The coupling reaction of a Nα-, NG-protected arginine with a Anb5, 2-resin was difficult to achieve by common coupling methods (such as the carbodiimide and diphenylphosphoryl azide methods), but the phosphoryl chloride method was relatively successful. Synthetic benzoyl-Arg-Anb5, 2-NH2 and benzoyl-Arg-pNA were hydrolyzed by trypsin and the both reaction mixtures exhibited same spectroscopic characteristics. H-D-Val-Leu-Arg-Anb5, 2-NH2, an analog of human urine kallikrein substrate, was readily prepared by the solid-phase method. H-Arg-Anb5, 2-OH and H-D-Val-Leu-Arg-Anb5, 2-OH were also synthesized on a Wang resin by the solid-phase method. The aqueous solubility of these free-carboxyl materials was better than those of the corresponding amide analogs. 4-Amino-3-nitrobenzoic acid (Anb4, 3) was also introduced on the p-methybenzhydrylamine resin, but the resulting H-Anb4, 3-resin did not react with Nα-, NG-protected arginine by any of the coupling methods.View full abstractDownload PDF (842K) -
Honghua CAO, Kentaro TANAKA, Mitsuhiko SHIONOYA2000 Volume 48 Issue 11 Pages 1745-1748
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA chelator-type β-C-nucleoside having a catechol ligand as the nucleobase was found to form a stable 2 : 1 complex with trimethyl borate, which was characterized by 1H-NMR and electrospray ionization time-of-flight (ESI-TOF) mass spectroscopies. Both phosphoramidite and phosphoriester derivatives of this nucleoside were also prepared as synthetic precursors for DNA oligomer syntheses.View full abstractDownload PDF (576K) -
Naoki NODA, Shinichi KUBOTA, Yoko MIYATA, Kazumoto MIYAHARA2000 Volume 48 Issue 11 Pages 1749-1752
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo optically active N-acetyldopamine dimers together with four phenolic monomers were isolated from the crude drug "Zentai, " a cast-off shell of the cicada of Cryptotympana sp. (Cicadidae). The former two were 2-(3', 4'-dihydroxyphenyl)-1, 4-benzodioxane derivatives carrying substituents at the 3 and 6 (or 7) positions, which are known to becomponents of sclerotized insect cuticles. Their structures including absolute configurations were determined on the basis of NMR and circular dichroism (CD) spectroscopic data.View full abstractDownload PDF (641K) -
Yoshihiro SATO, Masanori TAKIMOTO, Miwako MORI2000 Volume 48 Issue 11 Pages 1753-1760
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTotal synthesis of prostaglandin F2α utilizing a nickel(0)-catalyzed cyclization of 1, 3-diene and tethered aldehyde was achieved. The cyclization proceeded via a transmetalation of nickelacycle with diisobutylaluminum acetylacetonate (iBu2-ALAC). Thus, the reaction of 19, having a side chain corresponding to the α-chain in PGF2α with Ni(cod)2 (10 mol %), PPh3 (20 mol %), and 1, 3-cyclohexadiene (25 mol %) in the presence of iBu2-ALAC (1.5 eq) proceeded stereoselectively to give the cyclized product 26 in 54% yield. During the cyclization of 19, the Z-olefin at C-5 in the side chain completely retained its geometry, and the four contiguous chiral carbon centers in PGF<2α> were stereoselectively constructed. Transformation of the key intermediate 19 into PGF<2α> was successfully achieved.View full abstractDownload PDF (1408K) -
Bao-Zhong ZHENG, Megumi YAMAUCHI, Hiroo DEI, Osamu YONEMITSU2000 Volume 48 Issue 11 Pages 1761-1765
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA stereoselective synthesis is described of the C5-C13 fragment (4) of myriaporone 4 (1) starting from D-glucose by a coupling of the C5-C9 aldehyde (5), prepared using a regioselective reductive ring-opening of methoxy-benzylidene acetal, with the C10-C13 iodoolefin (6).View full abstractDownload PDF (921K) -
Dae Keun KIM, Ok Pyo ZEE2000 Volume 48 Issue 11 Pages 1766-1767
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new cyanogenic glycoside, sutherlandin-5-trans-p-coumarate was isolated along with a known cardiospermin-5-(4-hydroxy) benzoate from the aerial parts of Sorbaria sorbifolia (L.) A. Br. var. stellipila MAX. (Rosaceae). The structure of the new compound was established based on spectral evidence.View full abstractDownload PDF (377K) -
Lionel VIORNERY, Charles SALIBA, Jean Baptiste DASKIEWICZ, Christine B ...2000 Volume 48 Issue 11 Pages 1768-1770
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSPhytochemical investigation of the leaves of Umbilicus pendulinus afforded in addition to 2-O-caffeoyl malate, isoquercitrin and Z-venusol, the new isomer E-venusol. Special NMR experiments were carried out to elucidate the configuration of the two latter compounds.View full abstractDownload PDF (498K) -
Hafiz Rub NAWAZ, Abdul MALIK, Pir Muhammad KHAN, Shahida SHUJAAT, Atta ...2000 Volume 48 Issue 11 Pages 1771-1773
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA novel β-glucuronidase inhibiting triterpene (1) has been isolated from the chloroform fraction of Paeonia emodi. Its structure has been established as 1β, 3β, 5α, 23, 24-pentahydroxy-30-norolean-12, 20(29)-dien-28-oic acid on the basis of spectroscopic analysis, including high resolution mass spectroscopy, one and two-dimensional NMR techniques. Oleanolic acid, betulinic acid, ethyl gallate, methyl grevillate and 1, 5-dihydroxy-3-methyl-anthraquinone are also reported for the first time from Paeonia emodi.View full abstractDownload PDF (552K) -
Emika OHKOSHI, Mitsuko MAKINO, Yasuo FUJIMOTO2000 Volume 48 Issue 11 Pages 1774-1775
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA novel bisnorkaurenic acid-type diterpenelactone, named mikanialactone (1), was isolated along with five known kaurenic acid-type diterpenes (2-6) from the aerial parts of Mikania hirsutissima DC (Compositae). The structure of the new bisnorditerpene was determined by spectroscopic means.View full abstractDownload PDF (392K) -
William N. SETZER, Xuyuan GU, Eric B. WELLS, Mary C. SETZER, Debra M. ...2000 Volume 48 Issue 11 Pages 1776-1777
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe synthesis of a series of diacetylenic compounds related to the natural product falcarindiol has been carried out. Unsymmetrical diacetylenes were prepared by a modification of the Cadiot-Chodkiewicz coupling reaction, while a Glaser coupling was used to prepare symmetrical diacetylenes. These compounds have been tested for in vitro cytotoxic activity aginst Hep-G2, and H-4-II-E cell lines. Diacetylenes with additional unsaturation at C-1, 2, appended with hydroxyl groups at C-3 and C-8, or with long hydrophobic chains, exhibited IC50 values in the micromolar range.View full abstractDownload PDF (421K) -
Toshiyuki MATSUNO, Masanobu KATO, Hiroya SASAHARA, Tetsuo WATANABE, Ma ...2000 Volume 48 Issue 11 Pages 1778-1781
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTriamino-substituted 1, 3, 5-triazine and pyrimidine derivatives were synthesized and tested for antimtuor activities using some human cancer cell lines and murine leukemia cell lines. All the compounds having benzimidazolyl and morpholino groups as substituents on the 1, 3, 5-traizine ring showed antitumor activity. Pyrimidine derivatives having the same groups as substituents also showed antitumor activity. Among them, the compounds having 1-benzimidazolyl, morpholino and cis-2, 3-dimethylmorpholino groups as substituents on the 1, 3, 5-triazine ring or pyrimidine ring exhibited the most potent antitumor activity, and these compounds exhibited no or very weak aromatase inhibitory activity. In contrast, the compounds having imidazolyl group instead of benzimidazolyl group as a substituent on the 1, 3, 5-triazine ring showed a potent aromatase inhibitory activity.View full abstractDownload PDF (711K) -
Nobuyuki OKAMURA, Tomonori MAKI, Sachie ISHIDA, Chie URAGUCHI, Yuka ON ...2000 Volume 48 Issue 11 Pages 1782-1785
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWe describe here a method using HPLC for the simultaneous determination of albiflorin, paeoniflorin, glycyrrhizin and six flavanone glycosides (liquiritin, liquiritin apioside, naringin, neohesperidin, hesperidin and narirutin) in the Kampo medicines, Shigyaku-san and Haino-san. All nine components were separated in less than 40 min by linear gradient elution using a mobile phase containing aqueous phosphoric acid and acetonitrile. The dissolution of these components from powders of Shigyaku-san in aqueous solution at pH 1.80, 4.08 and 6.89 was examined. All of the components except glycyrrhizin were dissolved entirely within 5 min regardless of pH. Dissolution of glycyrrhizin was dependent on the pH of the aqueous solution, and increased with increasing pH.View full abstractDownload PDF (606K) -
Soon Sung LIM, Sang Hoon JUNG, Jun JI, Kuk Hyun SHIN, Sam Rok KEUM2000 Volume 48 Issue 11 Pages 1786-1789
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSInhibitory effects of synthetic 2'-hydroxychalcone derivatives on rat lens aldose reductase (RLAR) and on platelet aggregation were investigated for the prevention or the treatment of chronic diabetic complications. 5'-chloro-4, 2'-dihydroxychalcone (8) and 5'-chloro-3, 2'-dihydroxychalcone (27) exhbited a potent inhibitory effect on rat platelet aggregation induced by ADP (IC50=0.10 and 0.06 mg/ml, respectively) and collagen (IC50=44 and 16 μg/ml, respectively) but showed relatively weak inhibitory activities on RLAR.View full abstractDownload PDF (656K) -
Junko KOYAMA, Izumi MORITA, Akari KINO, Kinuko IWASA, Kiyoshi TAGAHARA2000 Volume 48 Issue 11 Pages 1790-1792
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA cyclodextrin modified capillary zone electrophoresis (CD-CZE) for the enantiomeric separation of tetrahydroprotoberberine N-metho salts was established. The resolution was optimized by changing the concentraion of the electrolyte solution, hydroxypropyl-β-CD (0.02 M, 0.07 M, or 0.14 M) or dimethyl-β-CD (0.05 M or 0.15 M) in phosphate buffer (pH 2.5 or 3) containing 10% acetonitrile with an applied voltage of 20 kV. This method was applied toward the enantioselective bio-conversion of quanternary tetrahydroprotoberberine N-metho salts in cultured cells of Corydalis species.View full abstractDownload PDF (511K) -
Tadashi KIHO, Takashi KOBAYASHI, Hotaka MORIMOTO, Shigeyuki USUI, Shig ...2000 Volume 48 Issue 11 Pages 1793-1795
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe structure of an anti-diabetic polysaccharide (TAP) obtained from the fruiting bodies of Tremella aurantia was investigated by methylation analysis, Smith degradation, partial acid hydrolysis, 13C-NMR spectrometry, and enzymatic digestion. The results suggested that TAP was composed of (1→3)-linked α-D-mannopyranosyl residues as a backbone, some of which were substituted at position 2 with (1→3)-linked β-D-xylopyranose side chains and with β-D-glucopyransyluronic acid at position 4 linked to terminal α-D-mannopyranose.View full abstractDownload PDF (505K) -
Hak Cheol KWON, Chil Mann JUNG, Cha Gyun SHIN, Jong Kyo LEE, Sang Un C ...2000 Volume 48 Issue 11 Pages 1796-1798
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe phytochemical study of the aerial parts of Aster scaber THUNB. (Asteraceae) yielded a new caffeoyl quinic acid, (-) 3, 5-dicaffeoyl-muco-quinic acid (2) and three known compounds, (-) 3, 5-dicaffeoyl quinic acid (1), (-) 4, 5-dicaffeoyl quinic acid (3), (-) 5-caffeoyl quinic acid (4). The structures were established by high resolution spectroscopic methods. The antiviral effects against HIV-1 integrase of the compounds was evaluated. (-) 3, 5-Dicaffeoyl-muco-quinic acid (2) exhibited potent antiviral activity with an IC50 value of 7.0±1.3 μg/ml.View full abstractDownload PDF (511K) -
Masayuki YAMASHITA, Kazunori OKUYAMA, Ikuo KAWASAKI, Seikou NAKAMURA, ...2000 Volume 48 Issue 11 Pages 1799-1802
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAlkylidenemalonates were readily dimerized in the presence of SmI2 to give 2, 3-disubsituted 1, 1, 4, 4-butanetetracarboxylates as mixtures of meso and racemic isomers in moderate to good yields. The structure of the less polar isomer of tetraethyl 2, 3-diphenyl-1, 1, 4, 4-butanetetracarboxylate was determined by X-ray crystallographic analysis to be the meso form. Characteristic 1H-NMR behavior of the meso and racemic isomers is also discussed.View full abstractDownload PDF (708K) -
Xiao-Ming DU, Ning-Yi SUN, Nobuto IRINO, Yukihiro SHOYAMA2000 Volume 48 Issue 11 Pages 1803-1804
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe glycosidic constituents of whole platns of Anoectochilus formosanus propagated by tissue culture were investigated. A new compound, 2-(β-D-glucopyranosyloxymethyl)-5-hydroxymethylfuran, along with the known compounds, 3-(R)-3-β-D-glucopyranosyloxybutanolide (kinsenoside), 3-(R)-3-β-D-glucopyranosyloxy-4-hydroxy-butanoic acid, 1-O-isopropyl-β-D-glucopyranoside, (R)-(+)-3, 4-dihydroxy-butanoic acid γ-lactone, 4-(β-D-glucopyranosyloxy)benzyl alcohol, (6R, 9S)-9-hydroxy-megastigma-4, 7-dien-3-one-9-O-β-D-glucopyranoside, and corchoionoside C were isolated.View full abstractDownload PDF (441K) -
Dong-Yun SHIN, Hwa-Soon KIM, Kyung-Hoon MIN, Soon-Sil HYUN, Soon-Ai KI ...2000 Volume 48 Issue 11 Pages 1805-1806
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA highly potent anti-MRSA sesquiterpenoid has been isolated from Ulmus davidiana var. japonica, which has been traditionally used to treat infectious diseases in Korea. This naturally occurring antibiotic was identified as mansonone F (1). This compound has been found to be highly active specifically against MRSA and showed an MIC range of 0.39-3.13 μg/ml which is comparable to that of vancomycin.View full abstractDownload PDF (416K) -
Maki YOSHIDA, Kenji MORI, Tetsuya WATANABE, Tetsuya HASEGAWA, Kenji SU ...2000 Volume 48 Issue 11 Pages 1807-1809
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe enhancing effect of electroporation on the in vitro skin permeation of benzoate was evaluated. Needle and ring electrodes made of Ag/AgCl were connected to an electrical power source, which produced exponentially decaying pulses. The needle electrode was kept in contact with the skin surface, and the ring electrode was positioned either on or under the skin. The electrical pulse was applied to abdominal hairless rat skin at 150-600 V every minute from 4 to 6 h during the 10-h permeation experiment. Skin permeation of benzoate was promoted by electroporation and the effect was increased by application of a higher voltage. No immediate recovery to the control flux, however, was observed for high voltage groups after turning off the voltage application. When the cathode and anode were separated by the skin membrane by setting in the epidermal and dermal sides, respectively, an iontophoretic effect may also play a role in benzoate flux. These results indicated that the drug permeation by electroporation is the result of passive diffusion and an iontophoretic effect as well as the electroporation effect.View full abstractDownload PDF (559K) -
Nobuko MIBU, Kunihiro SUMOTO2000 Volume 48 Issue 11 Pages 1810-1813
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe reactions of exophilic metal phenolates having electron-donating substituent (1a-c) with aromatic aldehydes (2, 3) were selectively condensed at the ortho-position of the starting phenol to afford 2, 2'-dihydroxy-triphenylmethanes (8-11). This method was also applicable to the preparation of bisphenols (12-17) starting with naphthaldehydes (4, 5) and pyridinecarboxyaldehydes (6, 7), but in low yields. In the case of these aldehydes (4-7), satisfactory yields could be obtained by sonication.View full abstractDownload PDF (629K) -
Reiko FUJITA, Masato HOSHINO, Hiroshi TOMISAWA, Hiroshi HONGO2000 Volume 48 Issue 11 Pages 1814-1817
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSDiels-Alder (DA) reactions of 2(1H)-pyrodines having an electron-withdrawing group at the 4-position with 2, 3-dimethoxy- and 2-methoxy-1, 3-butadienes gave isoquinoline derivatives. Furthermore, an isoquinoline alkaloid (6, 7-dimethoxy-2-methyl-1(2H)-isoquinolone) was synthesized by elimination of hydrogen cyanide and dehydrogenation of the DA-adduct having a cyano group at the 4a-position.View full abstractDownload PDF (659K) -
Fumihiro NAGASHIMA, Makoto SUZUKI, Shigeru TAKAOKA, Yoshinori ASAKAWA2000 Volume 48 Issue 11 Pages 1818-1821
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThree new clerodane-type diterpenoids have been isolated from the Japanese liverwort Jungermannia infusca (MITT.) STEPH., together with previously known compounds, nine clerodane- and four labdane-type diterpenoids, and δ-tocopherol. The structures of the new compounds were confirmed by 2D NMR experiments and X-ray crystallographic analysis.View full abstractDownload PDF (617K) -
Miyuki TAKAHASHI, Masakazu TANAKA, Eishi SAKAMOTO, Masanori IMAI, Kazu ...2000 Volume 48 Issue 11 Pages 1822-1825
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSRh-Catalyzed cyclization was applied to the formation of a chiral quaternary carbon. It has become clear that the Rh-complex can discriminate between isopropenyl and 2-isopentenyl (or isopentyl) substituents, and the cyclization afforded 3, 3, 4-trisubstituted cyclopentanones with a chiral quaternary carbon in a stereoselective manner. The cyclization of 4-pentenals 6a, b by an achiral neutral Rh(PPh3)3Cl afforded 3, 3, 4-cis-trisubstituted cyclopentanones (±)-7a, b in 86-96%, and the cyclization by a cationic Rh[(R)-BINAP]ClO4 afforded 3, 3, 4-trans-trisubstituted cyclopentanones (-)-8a, b of 82-86% ee in 88-98% yields. The mechanism of stereoselection by Rh-complexes is also discussed.View full abstractDownload PDF (737K) -
Motoyuki NAKAMURA, Katsumi KIDO, Junei KINJO, Toshihiro NOHARA2000 Volume 48 Issue 11 Pages 1826-1827
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo new actinidine-type monoterpene alkaloids, delavayines B (1) and C (2), were isolated from the MeOH extract of the aerial parts of Incarvillea delavayi, a close species of which, I. sinensis, is used as an analgesic for rheumatic pain in China, and the structures have been elucidated on the basis of spectroscopic evidence.View full abstractDownload PDF (380K) -
Takahiro UCHIDA, Yuka TOIDA, Yohko MIYANAGA, Kotoe MACHIDA, Koichi WAD ...2000 Volume 48 Issue 11 Pages 1828-1830
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSBasic amino acids were used as neutralizers in the gellation of Eudispert[○!R] as an acrylic hydrogel. Arginine and lysine successfully neutralized Eudispert[○!R], as did sodium hydroxide, and formed hydrogels. A gentle rise of pH was observed as the dosage of the base increased when arginine and lysine were used, in contrast to the sharp rise of pH observed when sodium hydroxide was used. The rank of viscosity of the prepared hydrogels was as follows : lysine>arginine>NaOH. The release rate of model drugs (salicylic acid, theophylline, and bovine insulin) from the prepared hydrogels ranked as follows : NaOH>lysine>arginine, the sustained-release profile being observed with arginine. The rate of diffusion of the model drug from the hydrogel was inversely proportional to the molecular weight of the cationized neutralizer used. It is concluded that the startegy of neutralization of acidic polymers by basic amino acids has advantage with the respect to both the sustained-release characteristics of the gel and the biocompatibility of the basic amino acids themselves.View full abstractDownload PDF (575K) -
Akimasa IWADO, Masaki MIFUNE, Jiro KATO, Junko ODA, Masahiko CHIKUMA, ...2000 Volume 48 Issue 11 Pages 1831-1832
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAnion-exchange resins modified with metal-prophine (M-Pr) have been investigated to develop a solid catalyst in the oxidative reaction of phenols by O2 in air. Co-Pr, which is easily prepared and separable from the reaction mixture, has been proved to accelerate the oxidative reaction of phenols such as 3, 5-di-tert-butyl-4-hydroxyanisole. The resulting main oxidative products were identified to be quinones by using the GC-MS method.View full abstractDownload PDF (426K) -
Chisato TODE, Yumiko YAMANO, Masayoshi ITO2000 Volume 48 Issue 11 Pages 1833-1834
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe first total synthesis of mytiloxanthin 2 was accomplished via the cyclopentyl ketone 7 prepared by stereoselective rearrangement of the epoxide 4a.View full abstractDownload PDF (414K) -
Hiroaki GOUDA, Toshiaki SUNAZUKA, Satoshi OMURA, Shuichi HIRONO2000 Volume 48 Issue 11 Pages 1835-1837
Published: November 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSMotilide, an erythromycin derivative, has been shown to equal activity to that of motilin as an agonist at the motilin receptor. However, there is little information on the three-dimensional (3D) structure-activity relationship between these two molecules, largely because they have quite different structures. In this study, we applied a rational computational procedure consisting of conformational analysis and a novel superposing method to investigate the 3D structure-activity relationship between motilide and motilin. We propose common 3D structural features between these molecules, which may be important for their similar activity.View full abstractDownload PDF (569K)