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Volume 38, Issue 10
Displaying 1-50 of 63 articles from this issue
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Fujio KAMETANI, Hakim BANGUN, Yukihiro IKEDA, Saburo SHIMABAYASHI1990 Volume 38 Issue 10 Pages 2623-2626
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe molar binding ratio (xpip) of piperazine (i.e., piperazinium ion) to a carboxylate group of alginate (Alg) was studied by using the titration/dialyzing method in a salt-free system. The value of xpip at the equivalence point of piperazine to alginic acid was far less than untiy, because the dominant ionic species of piperazine at the equivalence point (pH 5.0) was bivalent piperazinium cation. The ratio increased further with the amount of added piperazine, leveling off at unity after adding a sufficient quantity of piperazine, where the dominant species was univalent cation. On the other hand, competition of alkali metal ion with piperazinium ion for Alg was observed when MCl (M=Li+, Na+, or K+) was added. The effect was in the order of Li+>Na+>K+. The sum of xpip and xM (binding ratio of M) was almost unity even at low pH where dominant species of piperazine was bivalent piperazinium cation. This fact suggests that a bivalent piperazinium cation is bound to a carboxylate group of Alg through one of two positively charged sites while another site captures chloride anion as another counter ion by electrostatic force.View full abstractDownload PDF (777K) -
Hiroshi TAKAHASHI, Ichiro MORIMOTO, Kimio HIGASHIYAMA1990 Volume 38 Issue 10 Pages 2627-2631
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSNew chiral heterocyclic compounds, (3aS, 6R)-5-oxa-7, 8a-diazaperhydroazulen-8-ones (2a-c), were synthesized and their absolute configurations were determined by X-ray analysis. The reaction of (3aS, 6R)-2a-c with diethylzinc proceeded under mild conditions with extremely high diastereoselectivity.View full abstractDownload PDF (722K) -
Tohru HINO, Hideya UEHARA, Mika TAKASHIMA, Tomohiko KAWATE, Hiroko SEK ...1990 Volume 38 Issue 10 Pages 2632-2636
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe cyclic tautomer (5) of Nb-methyl-3-indoleacetamide (4) has been prepared by dissolving 4 in phosphoric acid. The bromination of 5 with 1 or 2 mol of N-bromosuccinimide (NBS) or 2, 4, 4, 6-tetrabromo-2, 5-cyclohexadienone (TABCO) gave the 5-bromo- (8) and the 5, 7-dibromo (9) derivatives. On the other hand, the 5-bromo derivative (11) was the major product of the bromination of the N-acetyl cyclic tautomer (6) even with 2 mol of NBS. The 5-nitro derivative (17) was obtained in excellent yield by the nitration of 6 with ammonium nitrate in trifluoroacetic anhydride (TFAA). Reduction of 17 followed by bromination gave the 4, 6-dibromo derivative (19), which gave the tribromide (20) in the Sandmeyer reaction. The 4, 5, 6-tribromo-3-indoleacetamide (7), which is the indole moiety of a marine indole alkaloid, chartelline A, was obtained by the ring opening of 20. Furthermore, the oxidation of 5 with lead tetraacetate followed by acetylation gave the 5-acetoxy derivative (22). The selective hydrolysis and bromination of 22 gave the 4, 6-dibromo-5-hydroxy derivative (24).View full abstractDownload PDF (878K) -
Mitsuaki WATANABE, Mutsuhiro DATE, Kenji KAWANISHI, Takako HORI, Sunao ...1990 Volume 38 Issue 10 Pages 2637-2643
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAryl tetramethylphosphorodiamidates were effectively ortho-lithiated with sec-BuLi in tetrahydrofuran at -105°C.The resulting lithiated species were trapped with a variety of electrophiles at -105°C to provide ortho-substituted phosphorodiamidates. When the lithiation was carried out at -78°C, O→C migration of the bis(dimethylamino)phosphoryl group took place rapidly and 2-hydroxyarylphosphonic tetramethyldiamides were produced regioselectively. The ortho-directing ability of the phosphorodiamidates was investigated by intermolecular competition experiments with other directed metalation groups.View full abstractDownload PDF (985K) -
Masayuki TANNO, Shoko SUEYOSHI, Shozo KAMIYA1990 Volume 38 Issue 10 Pages 2644-2649
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSNitrosation of 3, 3-dialkyl-1-(4-tolyl)ureas (9) with sodium nitrite in formic acid under ice-cooling gave 3, 3-dialkyl-1-(4-tolyl)-1-nitrosoureas (10). In the nitrosation of the ureas with a benzyl group, small amounts of dealkylated nitrosourea, 3-benzyl-1-(4-tolyl)-3-nitrosourea, were formed as a by-product. Decomposition of 10 in CCl4 at 33°C under an argon atmosphere gave 4-tolyl isocyanate (11) and N-nitrosodialkylamines (12) besides ureas (9), 3, 3-dialkyl-1-(2-nitro-4-tolyl)ureas (13) and 3, 3-dialkyl-1-(4-tolyl)triazenes (14). Formation of 11 and 12 suggests the involvement of an O-nitrosoisourea intermediate (15) in the decomposition of 10. In the thermolysis of 10 involving radical decomposition, nitric oxide generated from 10 was trapped as an NO3 complex of N, N'-etylenebis-(salicylideneiminato)iron (Fe(III)-salen-NO3).View full abstractDownload PDF (855K) -
Masateru ONO, Tomoji FUKUNAGA, Toshio KAWASAKI, Kazumoto MIYAHARA1990 Volume 38 Issue 10 Pages 2650-2655
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFour glycosidic acids, operculinic acids D, E, F and G, were isolated from the glycosidic acid fraction afforded by alkaline hydrolysis of the ether-soluble crude resin glycoside ("jalapin") from Rhizoma Jalapae Braziliensis (roots of Ipomoea operculata).They were respectively characterized as 11S-jalapinolic acid 11-O-β-D-glucopyranosyl-(1→3)-O-[α-L-rhamnopyranosyl-(1→4)]-O-α-L-rhamnopyranosyl-(1→4)-O-α-L-rhamnopyranosyl-(1→2)-β-D-xylopyranoside, 11S-jalapinolic acid 11-O-α-L-rhamnopyranosyl-(1→4)-O-α-L-rhamnopyranosyl-(1→4)-O-α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranoside, 11S-jalapinolic acid 11-O-α-L-rhamnopyranosyl-(1→4)-O-α-L-rhamnopyranosyl-(1→4)-O-α-L-rhamnopyranosyl-(1→2)-β-D-xylopyranoside and 11S-jalapinolic acid 11-O-(2-O-methyl-β-D-glucopyranosyl-(1→3))-O-[α-L-rhamnopyranosyl-(1→4)]-O-α-L-rhamnopyranosyl-(1→4)-O-α-L-rhamnopyranosyl-(1→2)-β-D-fucopyranoside, on the bases of chemical and spectroscopic data.View full abstractDownload PDF (774K) -
Taisuke ITAYA, Masatoshi MORISUE, Motoko TAKEDA, Yukinari KUMAZAWA1990 Volume 38 Issue 10 Pages 2656-2661
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe Vilsmeier-Haack reaction of 3-(2, 3, 5-tri-O-acetyl-β-D-ribofuranosyl)wye (7c) followed successively by reduction with sodium borohydride and catalytic hydrogenolysis afforded the 7-methyl derivative 12c, which provided the title compound 12a on deprotection. Compound 12c was more effectively produced by direct hydrogenolysis of the 7-formyl derivative 8c, especially by use of Pearlman's catalyst. Similar treatment of 1-benzyl-7-formylwye (14) led to a better synthesis of 7-methylwye (1b), the fluorescent base isolated from Archabacterial transfer ribonucleic acids. Although hydrogenolysis of the 6-formyl compound 11 took place smoothly even over ordinary palladium on charcoal to afford 12c, this route had a bottleneck in the step of transformation of 8c into 11.Compound 12a proved to be highly sensitive to acidic hydrolysis at the glycosyl bond and the rate determined in 0.1N hydrochloric acid at 25°Cwas virtually the same as that of 3-β-D-ribofuranosylwye (7a).View full abstractDownload PDF (1047K) -
Akikazu KAKEHI, Suketaka ITO, Hidetoshi ISAWA, Tsuneaki TAKASHIMA1990 Volume 38 Issue 10 Pages 2662-2666
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSome pyridinium 1-[[(2-substituted ethy)thio]thiocarbonyl]aminides (4a-h) were prepared in moderate yields by the reactions of N-unsubstituted pyridinium aminides (2a-e) with carbon disulfide and ethyl acrylate (3a) or acrylonitrile (3b). The S-alkylations of these aminides 4a-h with bromoacetonitrile (5a) or ethyl bromoacetate (5b) at room temperature and the subsequent treatment of the resulting pyridinium salts with 1, 8-diazabicyclo[5.4.0]undec-7-ene (DBU) and then with chloranil at 0°C gave the corresponding 2-[(2-substituted ethyl)thio]pyrazolo[1, 5-a]pyridine derivatives (6a-p) in 40-75% yields. The β-eliminations of the 2-substituents in these pyrazolo[1, 5-a]pyridines 6a-p with potassium tert-butoxide in N, N-dimethylfomamide (DMF) proceeded smoothly to provide the title compounds, pyrazolo[1, 5-a]pyridine-2-thiols (7a-j), in good yields along with the release of 3a, b.View full abstractDownload PDF (639K) -
Akikazu KAKEHI, Suketaka ITO, Tosio SAKURAI, Kunio URUSHIDO, Hidetoshi ...1990 Volume 38 Issue 10 Pages 2667-2675
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSVarious 2-(acylmethylthio)-, 2-(benzylthio)-, and 2-(propargylthio)pyrazolo[1, 5-a]pyridine derivatives (4a-n' and 7a-n') were prepared in moderate to good yields by the reactions of potassium pyrazolo[1, 5-a]pyridine-2-thiolates (2 and 6), readily available by the treatment of 2-[(2-ethoxycarbonylethyl)thio]- and 2-[(2-cyanoethyl)thio]pyrazolo[1, 5-a]pyridines (1a-h and 5a-h) with potassium tert-butoxide in N, N-dimethylformamide (DMF), with alkylating agents such as chloroacetone (3a), phenacyl bromides (3b-d), ethyl bromoacetate (3e), benzyl bromides (3f-k), and propargyl bromide (31). Of these S-functionalied pyrazolo[1, 5-a]pyridines only 2-(acetonylthio)- and 2-(phenacylthio)pyrazolo[1, 5-a]pyridine-3-carbonitriles (4a-t) were converted to new heterocyles, thieno[2', 3' : 3, 4]pyrazolo[1, 5-a]pyridines (8a-t) by heating them with 1, 8-diazabicyclo[5.4.0]undec-7-ene (DBU); the other compounds did not provide any tricyclic heterocycles under various alkaline conditions. The structures of thieno[2', 3' : 3, 4]pyrazolo[1, 5-a]pyridines (8a-t) were determined mainly by elemental analyses and spectral inspections, and the structural assignment was confirmed by the X-ray analysis of compound 8d.View full abstractDownload PDF (924K) -
Magoichi SAKO, Seiji OHARA, Kosaku HIROTA, Yoshifumi MAKI1990 Volume 38 Issue 10 Pages 2676-2680
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSPhotooxygenation of naphthalene (4), phenanthrene (5), pyrene (6), and benzo[a]pyrene (7) by pyrimido[5, 4-g]pteridine N-oxide (1) was examined in comparison with that of benzene. These polycyclic aromatic hydrocarbons (PAHs)consumed 1 more smoothly than did benzene under irradiation with ultraviolet-visible light, as expected from the fact that their oxidation potentials for conversion to the corresponding phenols and/or further oxidized products are lower. The photooxygenation of the PAHs occurred predominantly at the most reactive position of the corresponding cation-radicals. These and other experimental results led us to conclude that the PAHs are oxygenated via photo-induced single-electron transfer (SET) from the PAHs to 1 followed by oxygen-atom transfer between the resulting radical-ion pairs. The occurrence of the SET in an excited charge-transfer complex formed between the PAHs and 1 is at variance with the case of benzene. The photooxygenation of 7 by 1 can be regarded as a simple reaction mimic for one of the metabolic activation processes involved in carcinogenesis by 7.View full abstractDownload PDF (876K) -
Takashi YOSHIDA, Tong CHOU, Yasuhiko MARUYAMA, Takuo OKUDA1990 Volume 38 Issue 10 Pages 2681-2686
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo new dimeric hydrolyzable tannins, camelliins A and B, which exist as equilibrium mixtures of anomers, have been isolated from flower buds of Camellia japonica L., and their structures were elucidated. Camelliin B belongs to a unique class of dimers having a macrocyclic structure. The flower of Camellia sasanqua THUNB. yielded five tannins which were identical with those of C. japonica.View full abstractDownload PDF (879K) -
Shigetoshi KADOTA, Yasushi TAKAMORI, Khin Nyein Nyein, Tohru KIKUCHI, ...1990 Volume 38 Issue 10 Pages 2687-2697
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWoodfruticosin (woodfordin C), a new cyclic dimeric hydrolyzable tannin having an inhibitory activity toward deoxyribonucleic acid (DNA) topoisomerase II, has been isolated from the leaves of Woodfordia fruticosa KURZ (Lythraceae) along with three known flavonol glycosides and three known flavonol glycoside gallates. The structure of woodfruticosin (woodfordin C) was determined by the use of two-dimensional nuclear magnetic resonance (2-D NMR) spectroscopy including heteronuclear multiple quantum coherence (HMQC) and heteronuclear mucltiple bond connectivity (HMBC) techniques. Detailed analyses of the proton and carbon-13 NMR (1H-and 13C-NMR) spectra of six known flavonoids were performed.View full abstractDownload PDF (1183K) -
Toshikatsu TAKANAMI, Akie ABE, Kohji SUDA, Hidenobu OHMORI, Masaichiro ...1990 Volume 38 Issue 10 Pages 2698-2701
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSElectrochemical oxidation of triphenylphosphine (1) in dichloromethane containing allylsilanes (2) in an undivided cell afforded allyltriphenylphosphonium salts (3). The addition of 1 to 2 took place exclusively at the γ-position of 2 and the reaction was extended to provide a convenient method for the synthesis of cyclic phosphonium salts (3) bearing β-exo-methylene. The yields of 3 depended on the cathode material : use of a lead cathode, which has a high hydrogen overpotential, gave favorable results. Based on the results of the voltammetric study, the process of formation of 3 is suggested to involve electrophilic attack of the triphenylphosphine radical cation on 2 as the key step.View full abstractDownload PDF (659K) -
Tozo FUJII, Masashi OHBA, Miwa SAKARI, Satoshi MATSUBARA1990 Volume 38 Issue 10 Pages 2702-2706
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS(1'R)-1'-Methyl-cis-zeatin (2b) and its 9-β-D-ribofuranoside (4b) have been synthesized for the first time from D-alanine (5) in 7 steps. The new cis-zeatin derivatives 2b and 4b, together with known cis-zeatin (2a), were tested for cytokinin activity in the tobacco callus and the lettuce seed germination bioassays. In both bioassays, the cytokinin activity was found to follow the order 2a>2b>4b, indicating that 2b and 4b were less active than the corresponding trans isomers 1b and 3b (natural cytokinins from Pseudomonas syringae pv savastanoi), respectively.View full abstractDownload PDF (812K) -
Tsutomu HATANO, Akira OKONOGI, Kazufumi YAZAKI, Takuo OKUDA1990 Volume 38 Issue 10 Pages 2707-2711
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTrapanin A (6), a trimeric hydrolyzable tannin, and trapanin B (7), a tetrameric hydrolyzable tannin, were isolated from the leaves of Trapa japonica (Trapaceae), and their structures were determined on the basis of spectroscopic and chemical data. The following tannins were also isolated from the leaves : cornusiin C (8) (trimer); cornusiin A (3), camptothin B (4) and cornusiin D (5) (dimer); gemin D (1), tellimagrandin I (2), pedunculagin, casuarictin and casuarinin (monomer).View full abstractDownload PDF (682K) -
Nobuo IKOTA, Akira HANAKI1990 Volume 38 Issue 10 Pages 2712-2718
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS(-)-Swainsonine (1) and (-)-8-epi-swainsonine were synthesized from (S)- and (R)-glutamic acid derivatives. (2R, 3S, 4R)-3, 4-Dihydroxy-2-hydroxymethylpyrolidine derivatives (9a and 9b) were prepared by cis-dihydroxylation of α, β-unsaturated compounds 6, 10 and 15 with OsO4 as the key reaction. The diastereoselective allylation of the aldehydes 18 derived from 9a and 9g, followed by cyclization, gave 1 and (-)-8-epi-swainsonine.View full abstractDownload PDF (1293K) -
Tokumi MARUYAMA, Yoshiko SATO, Takahiko HORII, Hiroshi SHIOTA, Keiko N ...1990 Volume 38 Issue 10 Pages 2719-2725
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS9-Cyclobutyladenine (4a), cis- and trans-9-[3-(hydroxymethyl)cyclobutyl]adenine (4b) and 9-[3, 3-bis(hydroxymethyl)cyclobutyl]adenine(4d) were prepared from the corresponding cyclobutylamine derivatives (1a, 1b and 1d). Guanine congeners (9a, cis- and trans-9b and 9d) and carbocyclic oxetanocin G (1', 2'-trans-9f) were also prepared. Carbocyclic oxetanocin A(1', 2'-trans-4f), the preparation of which we have already published, and G were found to be active against herpes simplex virus (type 1 and 2) in vitro, while cis-4b and cis-9b showed an in vitro antiretrovial activity against human immunodeficiency virus (type 1).View full abstractDownload PDF (950K) -
Yoshifumi WATANABE, Hiroyuki USUI, Toshiro SHIBANO, Tsuyoshi TANAKA, M ...1990 Volume 38 Issue 10 Pages 2726-2732
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSNew serotonine 2(5-HT2) antagonists with a monocyclic or bicyclic 2, 4(1H, 3H)-pyrimidinedione have been prepared and their activities evaluated. In a series of monocyclic compounds, 1-substituted 5-phenyl-2, 4(1H, 3H)-pyrimidinedione 14 showed potent in vitro activity, and the corresponding 3-substituted 5-phenyl and 6-phenyl derivatives 3, 8 and 20a also showed moderate activity. In the bicyclic compounds, 3-substituted 5, 6, 7, 8-tetrahydro-2, 4(1H, 3H)-quinazolinedione 33 exhibited the most potent activity among the compounds prepared in this paper. The in vivo antagonist activity of 33 was comparable of that of ketanserin, a typical peripheral 5-HT2 antagonist.View full abstractDownload PDF (896K) -
Satoshi TERASHIMA, Mineo SHIMIZU, Hajime NAKAYAMA, Masatoshi ISHIKURA, ...1990 Volume 38 Issue 10 Pages 2733-2736
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFor several years we have screened natural products having aldose reductase (AR) inhibitory activity. 3, 3', 4-Tri-O-methylellagic acid 4'-sulfate potassium salt (2) was isolated from a Mexican herb "Sinfito" (Potentilla candicans) as a potent AR inhibitory active constituent. 2 was more potent (IC<50>=8.0×10<-8>M) than ellagic acid, which is one of the natural inhibitors of AR. So we examined the synthesis of ellagic acid derivatives and found that the sulfate group is one of the important function.View full abstractDownload PDF (719K) -
Midori TAKASAKI, Takao KONOSHIMA, Kazuyoshi FUJITANI, Shigeo YOSHIDA, ...1990 Volume 38 Issue 10 Pages 2737-2739
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwelve euglobals from Eucalyptus globulus and their twenty-six related compounds were examined for their inhibitory effects on Epstein-Barr virus activation by a short-term in vitro assay. The results showed that most of the euglobals having monoterpene structures, and euglobal-III (8) had strong inhibitory activity. Grandinol (18), homograndinols (19 and 20), and compounds 26, 27, 28, and 32 showed stronger inhibitory effects. Based on the results, the structural requirements for the activity of these compounds were discussed.View full abstractDownload PDF (542K) -
Toshimitsu HAYASHI, Kana OKAMURA, Masawo KAKEMI, Shinji ASANO, Motofum ...1990 Volume 38 Issue 10 Pages 2740-2745
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe structure of scopadulcic acid B (2, SDB), a major ingredient of the Paraguayan herb "Typycha kuratu" (Scoparia dulcis L.), was elucidated mainly by comparison of its spectral data with that of scopadulcic acid A (1). SDB inhibited both the K+-dependent adenosine triphosphatase (ATPase) activity of a hog gastric proton pump (H+, K+-ATPase) with a value of 20-30μM for IC50 and proton transport into grastric vesicles. Pharmacokinetic studies of SDB in rats indicated that plasma SDB concentrations after i.v. injection of the sodium salt of SDB (SDB-Na) were described reasonably well by a two-compartment open model with Michaelis-Menten elimination kinetics. Plasma concentrations after oral administration of SDB-Na or SDB showed a much slower decline than what was expected following the i. v. study. It was suggested that the sustained plasma level of SDB after oral administration of SDB-Na or SDB was accounted for by relatively slow but efficient gastro-intestinal absorption in rats.View full abstractDownload PDF (830K) -
Kazuo KOIKE, Katsuyoshi MITSUNAGA, Taichi OHMOTO1990 Volume 38 Issue 10 Pages 2746-2749
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFour new des-4-methylated picrasane type quassinoids, javanicins E, F, G and M, were isolated from the bark of Indonesian Picrasma javanica (Simaroubaceae). In addition, the known quassinoid, quassin, was also identified. The structures were determined by spectroscopic data and chemical evidence.View full abstractDownload PDF (583K) -
Tetsu OGATA, Shoji YAHARA, Reiko HISATSUNE(nee SAIJO), Ryoji KONISHI, ...1990 Volume 38 Issue 10 Pages 2750-2755
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIn a previous paper, we reported the isolation of the twenty-seven monomeric and dimeric isoflavonoid derivatives from the heartwood of Dalbergia odorifera T. CHEN (Leguminosae) and the structure elucidation of twelve monomeric and five dimeric isoflavonoids, which presented novel examples of naturally occuring biisoflavonoids. In a continuing study on this plant, we deal with the structure determination of four new dimeric flavonoids and a new arylbenzofuran among the uncharacterized compounds among the isolated ones.View full abstractDownload PDF (785K) -
Takeshi KINOSHITA, Koji ICHINOSE, Chiho TAKAHASHI, Feng-Chi HO, Jin-Bi ...1990 Volume 38 Issue 10 Pages 2756-2759
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo new pterocarpans, sophoracarpans A and B, were isolated from Sophora tomentosa L. (Leguminosae) in addition to three known isoflavonoids, wighteone (erythrinin B), sophoraisoflavanone A and l-maackiain. The structures of sophoracarpans A and B were elucidated as 6β, 9-dimethoxy-3-hydroxypterocarpan and 3-hydroxy-6β-methoxy-8, 9-methylenedioxypterocarpan, respectively, on the spectroscopic basis. The configurations at C-6, C-6a, and C-11a of both compounds were determined by a series of nuclear magnetic resonance irradiation experiments. The isoflavone wighteone, known as an antifungal phytoalexin in several genera of leguminous plants, was also found to occur in the genus Sophora.View full abstractDownload PDF (658K) -
Shigeru TABATA, Kentaro TANAKA1990 Volume 38 Issue 10 Pages 2760-2765
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe role of the ligand (oligosaccharide) of an Fe(II) complex (B1-c) produced in wine by Saccharomyces cerevisiae in gastrointestinal Fe absorption was examined. B1-c was found to consist of Fe(II) and an oligosaccharide having the composition of Ara : Xyl : Man : Glc : GalUA (1 : 1 : 1 : 5 : 1), and the sequence of these constituent monosaccharides was presumed by means of partial hydrolysis of B1-c with glycosidases and a diluted acid. The physicochemical comparison of the partially hydrolyzed, Fe(II)-containing products (Fe-containing fragments) obtained by glycosidase treatment indicated that the Man and GalUA residues of the ligand should be essential for stabilization of the complex form at the physiological pH in the digestive tract. The intestinal Fe absorption in vivo showed marked differences among the Fe-containing fragments having different ligands (sugar chains). Furthermore, the inhibitory effets of the Fe-containing fragments on B1-c uptake by brush border membrane vesicles of the small intestine varied with the ligand, probably being related to the composition of the sugar chain. These results suggest that the sugar chain of the ligand of B1-c may be involved, through its coordination with Fe(II), in (i) high stability and Fe solubility of B1-c at the physiological pH in the digestive tract and (ii) recognition of B1-c molecules in its transport system on the intestinal brush border membrane and, thereby, may contribute to excellent intestinal Fe absorption from B1-c.View full abstractDownload PDF (791K) -
Kenji AKASAKI, Yasunori YAMAGUCHI, Masaya OHTA, Fumito MATSUURA, Koji ...1990 Volume 38 Issue 10 Pages 2766-2770
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA major lysosomal membrane glycoprotein (LGP107) which has an apparent molecular weight (Mr) of 107 kilodaltons (kDa) was purified from rat liver by a simple method with a yield of 1mg/87g wet weight of liver. The purification procedures include; preparation of tritosomal membranes of triton-filled lysosomes (tritosomes), extraction of tritosomal membranes by Lubrol PX, wheat germ agglutin in (WGA)-Sepharose affinity chromatography, and monoclonal antibody-Sepharose affinity chromatography. The quantitative immunoblot analysis indicated that LGP107 represents 6.2% of the total protein of tritosomal membranes. The isoelectric point of the purified glycoprotein was 2.7, and it moved toward neutral pH after sialidase treatment, with its molecular weight decreased by about 10kDa. LGP107 contained 52% carbohydrates, and the carbohydrate moiety was composed of Fuc, Man, Gal, GlcNAc and sialic acid in a molar ratio of 7.2 : 68.2 : 40.6 : 63.0 : 32.3, respectively, indicating that LGP107 was highly glycosylated with N-linked complex-type oligosaccharide chains. Out of the N-linked glycans released from the glycoprotein by hydraziolysis/N-reacetylation, about 70% was sialylated. Anion exchange and reverse-phase high performance liquid chromatography analysis on the structure of N-glycans revealed that a disialy biantennary form is a major component in the oligosaccharide chains of LGP107.View full abstractDownload PDF (951K) -
Ryoko GONDA, Masashi TOMODA, Mieko KANARI, Noriko SHIMIZU, Haruki YAMA ...1990 Volume 38 Issue 10 Pages 2771-2774
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA novel acidic polysaccharide, designated as MVS-VI, was isolated from the seeds of Malva verticillata L. It was homogeneous on electrophoresis and gel chromatography, and its molecular mass was estimated to be 26000. It is composed of L-arabinose : D-xylose : D-galactose : D-glucose : L-rhamnose : D-galacturonic acid in the molar ratio of 30 : 15 : 20 : 3 : 2 : 10, in addition to small amounts of peptide moiety. Methylation analysis, carbon-13 nuclear magnetic resonance and periodate oxidation studies indicated its structural features to have mainly acidic α-arabino-3, 6-β-galactan type structural units. MVS-VI showed significant reticuloendothelial system-potentiating activity in a carbon clearance test, and it possesses remarkable anti-complementary activity.View full abstractDownload PDF (679K) -
Jian-Guo HU, Tsunehiro KITAGAWA1990 Volume 38 Issue 10 Pages 2775-2779
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe dose-response relationships of a viomycin (VM) immunogen for total immunoglobulin (Ig) G and anti-VM antibody response of mouse using aluminum hydroxide as adjuvant was studied. The condition required to absorb a protein on aluminum gel was first established. The effective immunogen dose for total and specific IgG response of mouse using aluminum hydroxide as the adjuvant was found to be in the narrow range of 5 to 20μg, and 10μg per mouse was optimal. The most effective number and intervals of booster injections were studied : when mice were immunized with a lower antigen dose than the optimal, both the number and interval period of booster injections greatly affected the immune response; the more boosters were given, the higher was the response level of specific IgG. The results are contrary to those obtained by immunizing with the optimal or a higher antigen dose.View full abstractDownload PDF (678K) -
Tomoko TAKAHASHI, Yoshio IKEGAMI, Masachika IRIE, Etsuko NAKAO1990 Volume 38 Issue 10 Pages 2780-2783
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo glucoamylases [EC 3.2.1.3] of Asperigillus saitoi, Gluc M1 (molecular weight (M.W.) 90000) and Gluc M2 (M.W.70000), which have similar pH optima and specific activities towards soluble starch were studied as to their behavior towards raw starch. The pH optima for raw starch digestion were different, 3.5 for Gluc M1 and 4.0 for Gluc M2. These enzymes digested raw starch almost completely but at quite different rates, Gluc M2 being 51 times less effective than Gluc M1. Gluc M1 tightly bound to raw starch with maximum binding occurring at pH 3.0. The binding constant K of Gluc M1 to raw starch at pH 3.0 and 4°C was 1.6×105M<-1>. In contrast, Gluc M2 which lacks the C-terminal region of Gluc M1, had as small a K value as 3.2×103M<-1>, with practically no binding to the raw starch. These results indicate that only Gluc M1 has an additional raw starch-binding site, besides the active center, in the C-terminal region.View full abstractDownload PDF (657K) -
Makoto HAGA, Katsumi SAITO, Junichi ANDO, Yuriko KATO1990 Volume 38 Issue 10 Pages 2784-2787
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe effects of two methods of preparing small unilamellar vesicles (SUV) (detergent removal or sonication) on their in vivo elimination and tissue distribution was investigated in rats. The SUV prepared by either method had the same size distribution and lipid composition (egg yolk phosphatidylcholine/cholesterol/dipalmitoyl phosphatidylethanolamine or palmitic acid=20/10/0.3, molar ratio). Three types of SUV made by either method were prrepared. These contained one of three different surface ligand-binding functional groups (N-hydroxysuccinimide ester of palmitic acid, NHSP; glutaraldehyde-phosphatidylethanolamine, GA-PE; N-[4-(p-maleimidophenyl)butyryl]phosphatidylethanolamine, MPB-PE). SUV prepared by detergent removal were eliminated slowly from the circulation, and exhibited a low liver uptake and little leakage of [3H]inulin. There was no significant difference in elimination of the NHSP-SUV, GA-SUV or MPB-SUV prepared by detergent removal and their tissue distribution was similar. In contrast, the sonicated SUV were eliminated from the circulation much more rapidly mainly by liver uptake. The leakage of [3H]inulin from sonicated SUV into urine was relatively large. When sonicated control-SUV were prepared in the presence of the antioxidant, α-tocopherol (α-T-SUV), which reduces lipid peroxidation during sonication, the α-T-SUV were eliminated slowly with only a low liver uptake. Our results indicate that the rapid elimination and greater liver uptake of sonicated SUV is partly due to lipid peroxidation during preparation. These findings have relevance to the use of liposomes as a drug delivery system.View full abstractDownload PDF (709K) -
Kazuto OHKURA, Kiyomi IWAMOTO, Hiroshi TERADA1990 Volume 38 Issue 10 Pages 2788-2791
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe permeation of nitrophenols through epidermal cells from newborn rat skin cultured on type IV collagen-coated Millipore filters was studied under various conditions. The order of permeation through the cultured skin cells was found to be p->m->o-nitrophenol at both 10 and 37°C. This order was the same as that of their affinities to isolated skin cells. The permeation of nitrophenols was not inhibited by the inhibitors of energy transduction 2-deoxyglucose and NaN3. These results suggest that the permeation of nitrophenols across a cultured cell layer occurs by simple diffusion. The order of permeation of nitrophenols across newborn abdominal epidermis was exactly the opposite of that of their permeation across a cultured cell layer.View full abstractDownload PDF (822K) -
Hajime TOGUCHI, Yasuaki OGAWA, Katsumi IGA, Takatsuka YASHIKI, Tsugio ...1990 Volume 38 Issue 10 Pages 2792-2796
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTo obtain information as to a suitable formulation of ethyl 2-chloro-3-[4-(2-methyl-2-phenylpropyloxy)-phenyl]propionate (AL-294), an antihyperlipidemic drug of low water solubility, the bioavailability after its oral administration in various dosage forms was evaluated in rats and dogs. After AL-294 was administered orally, AL-294 acid (2-chloro-3-[4-(2-methyl-2-phenylpropyloxy)phenyl]propionic acid), which is a metabolite of AL-294, was detected in the plasma. Therefore, absorbability of AL-294 was evaluated using plasma AL-294 acid levels. AL-294 in an oil solution or in a gelatin capsule showed poor absorption, whereas it's absorption was greatly enhanced in the form of an emulsion. The postprandial administration also showed batter absorption. The elimination rate of AL-294 acid from the plasma after oral administration of the emulsion was similar to that after intravenous administration of a sodium salt of AL-294 acid.View full abstractDownload PDF (661K) -
Hajime TOGUCHI, Yasuaki OGAWA, Tsugio SHIMAMOTO1990 Volume 38 Issue 10 Pages 2797-2800
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe effect of the physicochemical properties of the emulsion formulation on the absorption of ethyl 2-chloro-3-[4-(2-methyl-2-phenylpropyloxy)phenyl]propionate (AL-294) in rats and dogs was studied.When emulsions of different particle sizes were adiministered to rats, the higher the ratio of Tween-80 to the drug was, the smaller was the particle size and the higher was the absorption. When the emulsions of similar particle size (2μm) with different Tween-80 ratios were administered to rats, no significant difference was observed in the extent of absorption. The absorption of AL-294 was correlated with the dissolution rate from the oil phase to the aqueous phase but not correlated with the amount of AL-294 solubilized by Tween-80. These results indicate that the absorption of AL-294 from emulsions depends mainly on the particle size in the gastro-intestinal fluid and that Tween-80 serves only to reduce the particle size in the emulsion.View full abstractDownload PDF (601K) -
Hajime TOGUCHI, Yasuaki OGAWA, Katsumi IGA, Tsugio SHIMAMOTO1990 Volume 38 Issue 10 Pages 2801-2804
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe main absorption site of ethyl 2-chloro-3-[4-(2-methyl-2-phenylpropyloxy)phenyl]propionate (AL-294) in rats was the upper portion of the small intestine. Both AL-294 and AL-294 acid (2-chloro-3-[4-(2-methyl-2-phenylpropyloxy)phenyl]propionic acid), a hydrolyzed form of AL-294, were absorbed in a smaller quantity under the bile fistula condition (pancretic juice and bile were excluded). Compared with the absorption of AL-294 as an emulsion under the sham operation condition, the sbsorption of AL-294 as the emulsion decreased under the condition where only pancreatic juice was excluded. The bioavailability under this condition was very similar to that under the bile fistula condition, whereas the absorption of AL-294 acid did not decrease when the pancreatic juice was excluded. From these results, the absorption mechanism of AL-294 is considered as follows : AL-294 was hydrolyzed to AL-294 acid by lipase in pancreatic juice, then AL-294 acid was solubilized with bile salts to form mixed micelles in the intestinal lumen. AL-294 acid from this form was easily absorbed into the systemic circulation. Absorption of AL-294 increased when the particle size of the emulsion was smaller. The reason was assumed to be that the smaller particle size offered the greater oil-water interface for lipase activity against AL-294.View full abstractDownload PDF (630K) -
Rensuke GOTO, Hiroyuki KUBO, Yuko DAICHO, Shoji OKADA1990 Volume 38 Issue 10 Pages 2805-2809
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe interaction of 99mTc-labeled liposomes prepared from synthetic amphiphiles containing amino acid residues with Ehrlich ascites tumor cells in vitro and their tissue distribution in Ehrlich solid tumor-bearing mice were investigated. The amphiphiles used were N, N-didodecyl-Na-[6-(trimethylammonio)hexanoyl]-L-alaninamide bromide (N+C5Ala2C12), N, N-didodecyl-Na-{6-[dimethyl(2-carboxyethyl)ammonio]hexanoyl}-L-alaninamide bromide (CAC2N+C5Ala2C12) and S-{1-carboxy-2-([2, 3-bis(hexadecyloxy)propoxy]carbonyl)ethyl}homocysteine (HcyM-G2C16). Most of the radioactivity of N+C5Ala2C12 and CAC2N+C5Ala2C12 liposomes was firmly bound to Ehrlich ascites tumor cells in vitro. On the other hand, the accumulation of three 99mTc-labeled liposomes in the tumor of Ehrlich solid tumor-bearing mice was low (about 1% dose per gram of tissue), and most of the liposomes were taken up highly in the liver and spleen of the tumor-bearing mice. However, the radioactivity of the liposomes in the tumor, especially that of N+C5Ala2C12 and CAC2N+C5Ala2C12 liposomes, decreased more slowly with time than in the liver in up to 24 h after injection, suggesting that these liposomes were hard to separate from the tumor cells.View full abstractDownload PDF (792K) -
Hiroaki MIZUTA, Yasushi KAWAZOE, Kenji OGAWA1990 Volume 38 Issue 10 Pages 2810-2813
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSGastrointestinal absorption properties of chlorothiazide was investigated in dogs by a double-marker method using acetaminophen and salicylazosulfapyridine as the markers.The mean absorption time of acetaminophen (MATAAP) and the time for first appearance of sulfapyridine in plasma (TFASP) were used for the assessment of gastric emptying and oro-colonic transit times, respectively. Chlorothiazide absorption efficiency was increased by pretreatment with atropine sulfate. There was a good correlation between MATAAP and the extent of bioavailability of chlorothiazide, however, there was no correlation between TFA<SP> and the extent of bioavailability of the drug. These results indicate that chlorothiazide absorption takes place primarily in a limited segment of the upper small intestine, supporting the assumption reported previously. This double-marker method seems to be a useful tool for the investigation of the relationship between drug absorption and its gastrointestinal transit.View full abstractDownload PDF (586K) -
Shigeyuki ISHIKAWA, Masao KOBAYASHI1990 Volume 38 Issue 10 Pages 2814-2820
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTo understand the influence of powder properties on the viscoelasticity of a powder-filled semisolid, 8 powders (zinc oxide, titanium dioxide, hydrated sillicone dioxide, synthetic aluminum silicate, magnesium stearate, talc, cornstarch and glycyrrhetic acid) were added to macrogol ointment (MGO), and the viscoelasticity of the powder-filled MGO was investigated using the oscillation method at the rheological ground state and the continuous shear method at a high shear rate.As determined by the oscillation method, storage modulus (G') and loss modulus (G'') were increased in all cases by the addition of powders, suggesting the formation of a bridge structure through the particles. Though the increasing rate of G' or G'' on the weight fraction was different from powder to powder, a good linearity was maintained between logG' or logG'' and the square root of the contacting surface area (√(SA)), irrespective of the powder species. A master curve between log G' or log G'' and mean surface distance could be drawn. These simple relationships were more obvious than in the case of vaseline, studied previously. For this difference, it was presumed that in MGO, individual powder properties such as rigidity or lubricating function were masked by the more thickly adhered layers around the particles, and these thicker layers were formed due to the high consistency of MGO.As determined by the continuous shear method, the structures formed in MGO were susceptible to being ruptured easily. Thus, the powder properties seemed to have a stronger influence on the rheological properties at a higher shear rate than those at the rheological ground state.View full abstractDownload PDF (1062K) -
Jun WATANABE, Hiroya MURANISHI, Hisashi NAKAGAKI, Hiroaki YUASA, Shoji ...1990 Volume 38 Issue 10 Pages 2821-2824
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe effect of α-globulin, the dominant binding protein for fractionated 3H-heparin, on the hepatic uptake of 3H-heparin was studied by liver perfusion experiments in rats. Fractionated 3H-heparin concentration in the recirculated perfusate declined one-exponentially with time for each of six initial concentration levels of α-globulin. The hepatic uptake clearance of fractionated 3H-heparin was 0.154ml/min/g liver in the absence of α-globulin, and it decreased with increasing α-globulin concentrations. This result indicates that the hepatic uptake rate of α-globulin-boundfractionated 3H-heparin is lower than that of unbound fractionated 3H-heparin.On the other hand, it was indicated that almost all fractionated 3H-heparin binds to α-globulin at 8mg/ml of α-globulin in in vitro study. However, the hepatic uptake clearance of the heparin at the concentration was of a certain value that could not to be ignored. It was suggested that α-glonbulin-bound fractionated 3H-heparin also contributed to the hepatic uptake of fractionated 3H-heparin. Therefore, a protein-mediated transport system, which has been reported for some low molecular weight drugs, may also exist in the hepatic uptake of such a high molecular weight compound as fractionated 3H-heparin.View full abstractDownload PDF (640K) -
Hiroaki MIZUTA, Yasushi KAWAZOE, Kenji OGAWA1990 Volume 38 Issue 10 Pages 2825-2828
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe gastrointestinal absorption of 2-[3-(3, 5-di-tert-butyl-4-hydroxyphenyl)-1H-pyrazolo[3, 4-b]pyridin-1-yl]ethyl acetate (1), a new non-steroidal anti-inflammatory agent was investigated in dogs. A method using acetaminophen and salicylazosulfapyridine as the markers (double-marker method) was applied to trace the gastrointestinal transit of orally dosed 1. The mean absorption time of acetaminophen in plasma was used as an inidication of gastric emptying, and the first appearance time of sulfapyidine (a metabolite of salicylazosulfapyridine) in plasma was employed to detect the arrival of the marker to the colon. A remarkable inter-individual variation was observed in the absorption of 1. The extent of bioavailability was little affected by the gastric emptying time, but significantly influenced by the small intestinal transit time. Under a pretreatment with atropine, the transit time was prolonged to result in a significant enhancement of the bioavailability. Consequently, the absorption of 1 is confirmed to take place mainly in the small bowel.View full abstractDownload PDF (662K) -
Taro OGISO, Masahiro IWAKI, Akiko KANOKOGI, Yasuko TERAO1990 Volume 38 Issue 10 Pages 2829-2833
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIn order to estimate the pharmaceutical usefulness of 1, 3-glyceryl dinitrate (1, 3-GDN), an active metabolite of nitroglycerin, a trial transdermal delivery system designed to sustain a suitable plasma concentration of 1, 3-GDN was produced using a porous membrane (Hipore 2100 or 4500) and it was a gel base or ethylhexyl acrylate-based adhesive (adhesive) and it was applied to rats. Additionally, for practical use of the transdermal system, a simple pharmacokinetic model to describe plasma 1, 3-GDN levels after percutaneous (p.c.) application is presented.As a result, the drug was penetrated through the rat skin in vitro at a zero-order rate, although the penetration rate from the gel base was significantly greater than that from the adhesive. In vivo, the drug was rapidly absorbed through the rat skin, with a peak plasma level of 581±151 and 265±+62ng/ml for the gel ointment and adhesive systems without a porous membrane, respectively. The plasma levels after application of the systems with a membrane were relatively constant for a long time, indicating that the membranes act as a controlled-release barrier. The bioavailability of 1, 3-GDN after gel base systems with and without a membrane was relatively high. The model presented was successfully able to describe the time course of plasma 1, 3-GDN concentrations following p.c. application of the systems.View full abstractDownload PDF (754K) -
Makoto YOSHIHAMA, Kohji TAMURA, Masamichi NAKAKOSHI, Junji NAKAMURA, N ...1990 Volume 38 Issue 10 Pages 2834-2837
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSVarious derivatives of androst-4-ene-3, 17-dione derived from microbial transformation were evaluated as inhibitors of human placental aromatase. 14α-Hydroxyandrost-4-ene-3, 6, 17-trione was the most potent inhibitor showing a time-dependent, pseudo-first-order inactivation of aromatase in the presence of reduced nicotinamide adenine dinucleotide phosphate with apparent Ki of 1.3μM and Kinact of 0.23min-1. This compound also inhibited aromatase in rat ovary and suppressed serum estradiol levels in in vivo experiments.View full abstractDownload PDF (598K) -
Hiratoshi KATSUDA, Tadashi KOBAYASHI, Haruo SAITO, Takayuki MATSUNAGA, ...1990 Volume 38 Issue 10 Pages 2838-2840
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAn X-band electron spin resonance (ESR) imaging apparatus with a pin-hole TE102 mode cavity and a rapid scan coil was constructed. Using this apparatus, ESR imaging of melanin in mouse B16 melanoma was observed for the first time. The ESR spectrum of B16 melanoma is similar to that of natural melanin extracted from sepia officinalis in microwave power dependence.View full abstractDownload PDF (470K) -
Yoshiyasu KITAHARA, Tatsuya NAKAI, Masaro SHIMIZU, Akinori KUBO1990 Volume 38 Issue 10 Pages 2841-2846
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwenty-five 8-amino-5, 6-quinolinediones were prepared by copper(II)-catalyzed oxidation of 6-quinolinol in methanol with secondary amines, or by oxidative demethylation of the corresponding 5, 6-dimethoxyquinolines in aqueous acetonitrile with cerium(IV) ammonium nitrate.View full abstractDownload PDF (734K) -
Keizo MATSUO, Yoko HASUIKE, Harumi KADO1990 Volume 38 Issue 10 Pages 2847-2849
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS(-)-Malyngolide, which is an antibiotic isolated from a marine blue-green alga, was synthesized starting from D-lactose.View full abstractDownload PDF (543K) -
Takayoshi HIRAN0, Kenji INAGAKI, Takashi FUKAI, Maarten ALINK, Hideaki ...1990 Volume 38 Issue 10 Pages 2850-2852
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe asymmetric platinum complexes cis-Pt(LL')Cl2 (L=NH3, L'=CH3NH2, (CH3)2NH, C2H5NH2 and (C2H5)NH and LL'=N, N-dimethylethylenediamine), -one of the NH3 groups of cis-Pt(NH3)2Cl2 was substituted by alkylamine-, were synthesized and their cytotoxic effects have been measured using L-1210 cells. The IC50 values of the asymmetric platinum complexes, -being obtained after 24 h exposure of L-1210 cells to the platinum complexes-, are almost comparable to the corresponding value of cis-Pt(NH3)2Cl2. lIn 2 h exposure, however, the IC50 values of the platinum complexes were dramatically chaged, i.e., a marked difference was observed between those of L'=RNH2 and L'=R2NH. On the other hand, the amounts of platinum taken into the L-1210 cells is little affected by the alkylamino substitution. The results suggest that the bifunctional platinum binding to the target molecule may be responsible for the cytotoxicity.View full abstractDownload PDF (544K) -
Keiji KUBO, Katsuaki ODA, Tatsuhiko KANEKO, Hioroshi SATOH, Akira NOHA ...1990 Volume 38 Issue 10 Pages 2853-2858
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSMany 2-[[(4-fluoroalkoxy-2-pyridyl)methyl]sulfinyl]-1H-benzimidazoles were synthesized and tested for antisecretory, antiulcer, and cytoprotective activities. Most of these compounds were superior to omeprazole in antisecretory and antiulcer potencies, and especially in protecting the gastric mucosa from ethanol-induced damage. Among these compounds 2-[[[3-methyl-4-(2, 2, 2-trifluoroethoxy)-2-pyridyl]methyl]sulfinyl]-1H-benzimidazole, AG-1749 (lansoprazole) (6f), was selected for further development and clinical evaluation.View full abstractDownload PDF (791K) -
Masami KARIKURA, Toshio MIYASE, Hisayuki TANIZAWA, Yoshio TAKINO, Tosh ...1990 Volume 38 Issue 10 Pages 2859-2861
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe decomposition of ginsenoside Rb2 (Rb2) in the rat large intestine after oral administration was investigated in detail. A part of Rb2 was decomposed and six decomposition products (I-VI) were observed on thin-layer chromatogram. Among them, five products (I-V) were isolated, and identification of these compounds was done by carbon-13 nuclear magnetic resonance (13C-NMR).On the basis of 13C-NMR analysis, these compounds were identified as ginsenoside Rd (I), 3-O-β-D-glucopyranosyl-20-O-[α-L-arabinopyranosyl(1→6)-β-D-glucopyranosyl]-20(S)-proto-panaxadiol (II), ginsenoside F2 (III), 20-O-[α-L-arabinopyranosyl(1→6)-β-D-glucopyranosyl]-20(S)-protopanaxadiol (IV), and compound K (V), respectively.View full abstractDownload PDF (556K) -
Atsushi NUMATA, Chika TAKAHASHI, Ryoko FUJIKI, Eisaku KITANO, Akihiko ...1990 Volume 38 Issue 10 Pages 2862-2865
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThree antifeedants for larvae of the yellow butterfly, Eurema hecabe mandarina DE L'ORZA, were isolated from Osmunda japonica THUNB. and identified as osmundalin, parasorboside and methyl (3S, 5S)-5-hydroxy-3-(β-D-glucopyranosyloxy)hexanoate. In the course of isolation of the antifeedants. a new glycoside, dihydroisoosmudalin (9), was isolated together with maltol β-D-glucopyranoside, 2-deoxy-L-ribopyranolactone, 5-hydroxymethyl·2-furfural and glycerin. The structure of 9 was elucidated as (4R, 5S)-5-(β-D-glucopyranosyloxy)hexan-4-olide on the basis of chemical and spectroscopic evidence.View full abstractDownload PDF (537K) -
Kazushi SHINGU, Yoriko FURUSAWA, Nobuhiro MARUBAYASHI, Ikuhiko UEDA, S ...1990 Volume 38 Issue 10 Pages 2866-2867
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe structure of a new withanolide, (17R, 20R, 22R, 25R)-21, 24R-epoxy-27-methoxy-1-oxowitha-2, 5-dienolide, isolated from the methanolic extract of the fresh aerial parts of Datura metel L. (Solanaceae), was established by X-ray analysis.View full abstractDownload PDF (338K) -
Kazutaka TANIZAWA, Takashi MIYAURA, Yuichi KANAOKA1990 Volume 38 Issue 10 Pages 2868-2870
Published: October 25, 1990
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIn our previous work a new method for the cross-linking of protein was proposed. The method is based on the spontaneous chelate formation process between salicylaldehyde and α-amino acid residues. Thus, the facile procedure for the introduction of these residues into protein is required. In this paper, a modification reagnent which affords γ-glutamylation products, i.e., introducing an α-amino acid functional group to the protein was proposed. Versatility of the reagent for the preparation of a cross-linked enzyme was examined.View full abstractDownload PDF (609K)