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Volume 43, Issue 12
Displaying 1-44 of 44 articles from this issue
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Masayuki KUZUYA, Yukinori YAMAUCHI, Junji NIWA, Shin-ichi KONDO, Yoko ...1995 Volume 43 Issue 12 Pages 2037-2041
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWe report here the specific features of plasma-induced free radicals of cellulose derivatives such as ethylcellulose (EC) and hydroxyethylcellulose (HEC) on its comparison with those of cellulose. The electron spin resonance (ESR) spectra of Ar plasma-irradiated EC and HEC consist of three kinds of discrete spectral components, two isotropic spectra [doublets (I) and triplets (II), both being assigned to hydroxylalkyl radicals] and one anisotropic spectrum [doublet of doublets (IV) assigned to an acylalkyl radical], and a single broad line spectrum (III). The special feature here is the fact that the spectrum (III) is a major component, contrary to cellulose, which was assigned to an immobilized dangling-bond site (DBS) at the cross-linked region. The results suggest that plasma-induced cross-linking reactions are very predominant in EC and HEC relative to that of cellulose, due to the presence of alkyl substituents in EC and HEC.View full abstractDownload PDF (659K) -
Jun-ichi UEDA, Akira HANAKI, Naoko YOSHIDA, Terumi NAKAJIMA1995 Volume 43 Issue 12 Pages 2042-2047
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe complexation of Zn(II) with glycyl-L-histidylglycine and its deuterated derivatives, glycyl-d2-L-histidyl-glycine and glycyl-L-histidylglycine-d2, was studied by proton nuclear magnetic resonance spectroscopy over the pD range, from 3.4 to 11.0, at 25°C. Addition of Zn(II) to the peptide made the resonances of both imidazole C2-H and C4-H and both methylene-protons of glycyl residues at the amino-terminal and carboxylate end split to three lines in the pD range above 7.0. From the behavior of the C2-H and C4-H chemical shifts, formation of at least two species, in which the imidazole and amino nitrogens coordinated to the metal ion forming a chelate ring, was suggested. Those two species, the ratio of which varied depending on the total concentrations of complexes, seemed to be interconvertible; one referred to as B is a monomer and the other, referred to as C, may be a dimeric or polymeric complex.View full abstractDownload PDF (733K) -
Kiyoshi YOSHIKAWA, Kazuo ACHIWA1995 Volume 43 Issue 12 Pages 2048-2053
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWe have prepared several new, efficient, chiral N-acyl pyrrolidine carboxylic acid ligands for dirhodium-catalyzed asymmetric cyclopropanation and found that the steric and electronic effects of the rhodium(II) complexes and substrates influenced the enantioselectivity and catalytic activity. These electron-rich catalysts were shown to be efficient for asymmetric cyclopropanation using 1-chloro-1-fluoroethylene as a substrate.View full abstractDownload PDF (855K) -
Tokunaru HORIE, Yasuhiko KAWAMURA, Hitoshi YAMAMOTO, Kazuyo YAMASHITA1995 Volume 43 Issue 12 Pages 2054-2063
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe methoxymethyl ethers of 6-hydroxy-5, 7, 8-trimethoxyflavones, which were derived from 2', 5'-dihydroxy-3', 4', 6'-trimethoxyacetophenone, were oxidized with dimethyldioxirane to give the corresponding 3-hydroxyflavones. Selective O-alkylation and dealkylation of the 3-hydroxyflavones were examined and a convenient method for synthesizing the following ten kinds of 3, 5, 6, 7, 8-pentaoxygenated flavones was established : 3-hydroxy-5, 6, 7, 8-tetramethoxyflavones, 3, 5-dihydroxy-6, 7, 8-trimethoxyflavones, 3, 6-dihydroxy-5, 7, 8-trimethoxyflavones, 3, 5, 6-trihydroxy-7, 8-dimethoxyflavones, 3, 5, 6, 7-tetrahydroxy-8-methoxyflavones, and their 3-methyl ethers. Furthermore, 3, 5, 8-trihydroxy-4', 6, 7-trimethoxyflavone, 3, 8-dihydroxy-4', 5, 6, 7-tetramethoxyflavone, and 5, 8-dihydroxy-3, 6, 7-trimethoxyflavones were similarly synthesized and their spectral properties were examined. Additionally, the proposed structures of three natural flavones were revised.View full abstractDownload PDF (1308K) -
Katsumi YAMAMOTO, Jyunichi KOYANAGI, Ikuko HORIE, Masayuki OGAWA, Kats ...1995 Volume 43 Issue 12 Pages 2064-2067
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSMethyl 5-(2-carboxyphenylthio)-2-furancarboxylate (2) was obtained by the nucleophilic substitution of methyl 5-nitro-2-furancarboxylate (3) with the disodium salt of thiosalicylic acid, and chlorination of 2 gave methyl 5-(2-chloroformylphenylthio)-2-furancarboxylate (4). The reaction of 4 with sodium azide gave methyl 5-(2-azidocarbonylphenylthio)-2-furancarboxylate (8) and methyl 5-(2-isocyanatophenylthio)-2-furancarboxylate (9) was obtained by the thermolysis of 8. Finally, the new tricyclic compound, 5H-2-methoxycarbonyl-4-oxofuro[2, 3-b][1, 5]benzothiazepine (1) was obtained by cyclization of 9 in the presence of aluminum chloride.View full abstractDownload PDF (662K) -
Tadashi HASHIMOTO, Kazuhiro OHKI, Naoki SAKURA1995 Volume 43 Issue 12 Pages 2068-2074
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe susceptibility of the pyroglutamyl-peptide bond in some biologically active peptides, dog neuromedin U-8 fragment (pGlu-Phe-Leu-Phe-Arg-Pro-Arg-OH), human big gastrin fragment (pGlu-Leu-Gly-Pro-OH) and thyrotropin releasing hormone (TRH) fragments (pGlu-His-Pro-OH, pGlu-His-OH), to 1N HCl under mild conditions and/or at 60°C was studied. It was found that the N-terminal portion of pGlu-peptides is extremely labile to acid hydrolysis, giving not only the ring-opened product of the pyrrolidone of the pGlu residue, but also the cleavage product of the pGlu-peptide linkage. The ring-opening reaction predominated over the cleavage reaction in hydrolysis of the four peptides in 1N HCl at 60°C. The ring-opening reaction and the cleavage reaction of pGlu-peptide linkage proceeded faster than the cleavage of internal peptide bonds. The rate of hydrolysis was affected by the reaction temperature, and the ring-opening reaction was greatly diminished at 4°C in comparison with the cleavage reaction. Thus, the phenomenon that the pGlu-peptide bond is susceptible to dilute HCl as compared to the other peptide bonds appears to be a general one.View full abstractDownload PDF (1045K) -
Masayuki YAMASHITA, Kazunori OKUYAMA, Takashi OHHARA, Ikuo KAWASAKI, K ...1995 Volume 43 Issue 12 Pages 2075-2081
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe cyclopropane ring in 2-substituted 1, 1-cyclopropanedicarboxylates was regioselectively opened by using samarium(II) diiodide (SmI2) in a hexamethylphosphoric triamide (HMPA)-tetrahydrofuran (THF) (1 : 10) system under mild and neutral conditions to give (2-substituted ethyl)malonates in moderate to good yields. The cyclopropane ring in 2-substituted cyclopropanecarboxylates or 2-substituted 3-(trimethylsilyl)cyclopropanecarboxylates was similarly cleaved regioselectively by using SmI2 in a HMPA-THF (1 : 1) system to give 4-arylbutyrates or 4-aryl-3-(trimethylsilyl)butyrates in 16-89% yields. The reaction mechanism of these ring-opening reactions is discussed.View full abstractDownload PDF (968K) -
Kunihiko ITOH, Haruo SEKIZAKI, Eiko TOYOTA, Kazutaka TANIZAWA1995 Volume 43 Issue 12 Pages 2082-2087
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSNα-(tert-Butyloxycarbonyl)peptide p-guanidinophenyl esters were synthesized by amidination of Nα-(tert-butyloxycarbonyl)peptide p-aminophenyl esters with 1-[N, N'-bis(benzyloxycarbonyl)amidino]pyrazole, followed by deprotection by catalytic hydrogenation, in good total yields. These synthetic esters were characterized as specific substrates for trypsin, and kinetic parameters for the trypsin-catalyzed hydrolysis are presented.View full abstractDownload PDF (910K) -
Lih-Geeng CHEN, Ling-Ling YANG, Kun-Ying YEN, Tsutomu HATANO, Takashi ...1995 Volume 43 Issue 12 Pages 2088-2090
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThree hydrolyzable tannins of new types, glochiins M1, M2 and C1, were isolated from dried leaves of Glochidion rubrum BLUME, and their structures were elucidated by spectral and chemical methods.View full abstractDownload PDF (504K) -
Keizo MATSUO, Takahiko ARASE1995 Volume 43 Issue 12 Pages 2091-2094
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new pyridone alkaloid, cerpegin, was synthesized in five steps starting from the Michael reaction between phenylthioacetonitrile and 2-methoxycarbonyl-4-methyl-2-penten-4-olide. Catalytic hydrogenation of a nitrile group in the presence of a conjugated carbon-carbon double bond was performed by addition of 1 eq of concentrated HCl.View full abstractDownload PDF (673K) -
Makoto TANAKA, Toshitsugu KAI, Xue-Long SUN, Hiroaki TAKAYANAGI, Kimio ...1995 Volume 43 Issue 12 Pages 2095-2098
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSN-Glycolyl-8-O-sulfoneuraminic acid (1) was synthesized for the first time in good yield. The key intermediates for synthesis of 1, neuraminic acid O-benzyl α-glycoside (3) and neuraminic acid S-methyl α-glycoside (10) were prepared from readily available N-acetylneuraminic acid. The structures of these compounds were confirmed by analysis of their NMR spectra.View full abstractDownload PDF (741K) -
Takashi MATSUMOTO, Yoshio TAKEDA, Masaki OIWAMOTO, Kazunari FUJII, Mas ...1995 Volume 43 Issue 12 Pages 2099-2104
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSVeratraldehyde was condensed with methyl 2-chloropropanoate to give a glycidic ester. This was hydrolyzed with aqueous sodium hydroxide and the resulting sodium salt was treated with lead(IV) tetraacetate to give 1-acetoxy-1-(3, 4-dimethoxyphenyl)propan-2-one (13). Condensation of 13 with dimethyl malonate, followed by acidic hydrolysis and sodium borohydride reduction afforded (2R*, 3S*, 4R*)-4-(3, 4-dimethoxyphenyl)-2-methoxycarbonyl-3-methyl-4-butanolide (7a). The γ-lactone 7a was then converted into 5'-demethoxyporosin (10) by means of a series of reactions : Michael reaction with methyl vinyl ketone, elimination of the methoxycarbonyl group, acetalization, allylation, deacetalization, and intramolecular aldol reaction. Introduction of a hydroxyl group at the C-5' position in 10, followed by methylation with diazomethane afforded racemic porosin. The synthetic porosin was further converted into 5-demethoxymegaphone acetate.View full abstractDownload PDF (1002K) -
Kyung-Sik SONG, Soo-Muk CHO, JaeHoon LEE, Hwan-Mook KIM, Sang-Bae HAN, ...1995 Volume 43 Issue 12 Pages 2105-2108
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSHot water extract prepared from the mycelial culture of mushroom Phellinus linteus stimulated polyclonal antibody production in an in vitro culture system. The active fraction PLP was purified from the extract ca. 1030-fold by ethanol precipitation followed by DEAE-cellulose and gel permeation chromatography. PLP contained 13.2% (w/w) peptide and 82.5% (w/w) carbohydrate. About 6.8% (w/w) of the total carbohydrate was uronic acid. The molecular weight distribution of PLP was found to be nearly homogeneous (153kDa) in gel permeation HPLC analysis. Neutral sugar composition analysis revealed Ara (7.0%), Xyl (3.7%), Glc (21.1%), Gal (24.1%) and Man (44.2%). Uronic acid was identified as a glucuronic acid by gas chromatography. Ten amino acids were detected and Asp and Glu were the major components. In our assay system, the half-maximal concentration of PLP for B-lymphocyte stimulation was ca. 3μg/ml. Partial acid hydrolysis as well as sodium periodate treatment of PLP decreased the activity significantly, suggesting that both the full molecular size and the sugar moiety were essential. However, proteinase K treatment for up to 48h did not affect the activity.View full abstractDownload PDF (781K) -
Li HAN, Tsutomu HATANO, Takuo OKUDA, Takashi YOSHIDA1995 Volume 43 Issue 12 Pages 2109-2114
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThree new complex tannins, stachyuranins A (1), B (2) and C (3), were isolated from the leaves of Stachyurus praecox (Stachyuraceae), and their structures, each consisting of a catechin or gallocatechin residue and a monomeric hydrolyzable tannin moiety, were assigned. Structures 1 and 2 lack a C-C linkage between glucose C-1 and the aroyl group at glucose O-2, suggesting that they may be biogenetic precursors of complex tannins with the C-C linkage.View full abstractDownload PDF (832K) -
Masayuki YOSHIKAWA, Toshiyuki MURAKAMI, Takahiro UENO, Masashi KADOYA, ...1995 Volume 43 Issue 12 Pages 2115-2122
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSE-Senegasaponins a, b, and c were isolated from Senegae Radix, the root of Polygala senega L. var. latifolia TORREY et GRAY, together with their Z-isomers of the 4"-methoxycinnamoyl moiety, Z-senegasaponins a, b, and c. The structures of E-senegasaponins a and b and Z-senegasaponins a and b have been elucidated on the basis of chemical and physicochemical evidence, and the geometrical isomeric structure of the 4"-methoxycinnamoyl group in each saponin was found to show tautomer-like behavior in methanol solution or under irradiation with fluorescent lamps.E and Z-Senegasaponins a and b were found to exhibit potent inhibitory effects on alcohol absorption and hypoglycemic activity in the oral D-glucose tolerance tests in rats, and some structure-activity relationships of the acylated bisdesmoside-type saponins were clarified.View full abstractDownload PDF (1124K) -
Masahiro FUJITA, Hiroshi EGAWA, Masahiro KATAOKA, Teruyuki MIYAMOTO, J ...1995 Volume 43 Issue 12 Pages 2123-2132
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS4, 5-Disubstituted 6-cyclopropyl-6, 9-dihydro-9-oxo-1H-imidazo- (30-32) and triazolo[4, 5-f]quinoline-8-carboxylic acids (33-35) were synthesized starting from 5, 6-diaminoquinolones 25. The imidazoquinolones 30-32 were equal or superior to the corresponding triazoloquinolone analogues 33-35 in in vitro antibacterial activity. As for the C-5 substituents, a fluorine atom was the most favorable of the three groups, H, F, and Cl. Among the compounds prepared, 4-(cyclic amino)-5-fluoro-imidazoquinolones 31a-d showed potent and well-balanced antibacterial activity against both gram-positive and gram-negative bacteria. Structure-activity relationships for the C-4 substituents (cyclic amino groups) were also examined in detail.View full abstractDownload PDF (1499K) -
Koichi KAWASAKI, Machiko NAMIKAWA, Yuko YAMASHIRO, Yuji IWAI, Takao HA ...1995 Volume 43 Issue 12 Pages 2133-2138
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSHybrids of fibronectin-related peptides [Arg-Gly-Asp (RGD), Arg-Gly-Asp-Ser (RGDS)] and poly(ethylene glycol) (PEG) were prepared and their inhibitory effects on experimental metastasis in mice were examined. The inhibitory effect of RGD was markedly potentiated by hybrid formation with poly(ethylene glycol) #6000. As to inhibitory effect, RGD was more potent than RGDS and RGD PEG hybrids were superior to RGDS PEG hybrids. Hybrid formation with PEG #6000 was more effective than that with PEG #4000.View full abstractDownload PDF (938K) -
Kikuo ISHIZUMI, Atsuyuki KOJIMA, Fujio ANTOKU, Ikutaro SAJI, Mayumi YO ...1995 Volume 43 Issue 12 Pages 2139-2151
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSCyclic imides bearing ω-(4-benzisothiazol-3-yl-1-piperazinyl)alkyl moieties were synthesized and tested for antipsychotic activity. The in vitro binding affinities of these compounds were examined for dopamine 2 (D2) and serotonin 2 (5-HT2) receptor sites. Structure-activity relationships within these series are discussed. One of these compounds, N-[4-[4-(1, 2-benzisothiazol-3-yl)-1-piperazinyl]butyl]-1, 2-cis-cyclohexanedicarboximide (SM-9018), was found to be more potent and more selective in vivo than tiospirone in its antipsychotic activity. SM-9018 (17) is currently undergoing clinical evaluation as a selective antipsychotic agent.View full abstractDownload PDF (1571K) -
Akira KATO, Yuko IKEDA, Norifumi SUGITA, Toyohiko NITTA, Hiroyuki ENAR ...1995 Volume 43 Issue 12 Pages 2152-2158
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo series of 1, 2-disubstituted imidazolylmethylcyclopentanol derivatives (5a-d, 10a-d) were prepared by using easily available metyl 2-oxocyclopentanecarboxylate as the starting material. Evaluation of the aromatase inhibitory activities in vitro was performed. Their activities were compared with those of a steroidal aromatase inhibitor, Formestane, and a non-steroidal inhibitor, Fadrozole. Among these compounds, the aromatase inhibitory activities of 5d, 10a, 10b, 10c, 11a, 15a, and 15b were more potent than Formestane. One compound, 1-(4-chlorobenzyl)-cis-2-(1H-imidazol-1-ylmethyl)cyclopentanol (10a) was in particular identified as a potent aromatase inhibitor in vitro, exhibiting an IC50 value of 4×10-8M. The enantiomers of 10a were separated, and their absolute configurations were determined by X-ray crystallography.View full abstractDownload PDF (1101K) -
Masato SATOH, Yutaka KONDOH, Yoshinori OKAMOTO, Akito NISHIDA, Keiji M ...1995 Volume 43 Issue 12 Pages 2159-2167
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA novel series of 1-aroylmethyl-1, 3-dihydro-2H-1, 4-benzodiazepin-2-one derivatives was prepared and evaluated for activity as gastrin/cholecystokinin (CCK)-B receptor antagonists. In vitro binding studies showed that some derivatives exhibited potent affinity for gastrin/CCK-B receptor and high selectivity over peripheral CCK (CCK-A) receptor. Furthermore, these compounds potently inhibited pentagastrin-induced gastric acid secretion upon intravenous administration in an in vivo model in rats. Structure-activity relationship studies of this series suggested that 1-[(R)-2, 3-dihydro-1-(2-methylphenacyl)-2-oxo-5-phenyl-1H-1, 4-benzodiazepin-3-yl]-3-(3-methylphenyl)urea (35b, YM022) was the optimal compound with IC50 values of 0.17, 0.11 and 150nM for gastrin, CCK-B and CCK-A receptors, respectively, and an ED50 value of 9.5nmol/kg (i.v.) in rats. The absolute configuration of the precursor of YM022, an (R)-3-amino-1, 3-dihydro-2H-1, 4-benzodiazepin-2-one derivative ((R)-25), was determined by X-ray crystallographic analysis of its (S)-mandelate.It would be expected that YM022, a potent and selective gastrin/CCK-B receptor antagonist, inhibits gastric acid secretion without inducing gastrin-mediated side-effects such as hypergastrinemia and hyperplasia of oxyntic mucosa.View full abstractDownload PDF (1090K) -
Takashi SOHDA, Hitoshi IKEDA, Kanji MEGURO1995 Volume 43 Issue 12 Pages 2168-2172
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe metabolites of (±)-5-[p-[2-(5-ethyl-2-pyridyl)ethoxy]benzyl]-2, 4-thiazolidinedione (1, pioglitazone), which is a representative insulin-sensitizing agent, were synthesized to confirm their structures and for studies of their pharmacological properties. Of the metabolites identified, a compound hydroxylated at the 2-position of the ethoxy chain (3) and compounds oxygenated at the ethyl side chain attached to the pyridine ring (4, 5) were found to be active, although the potency was slightly lower than that of the parent compound.View full abstractDownload PDF (728K) -
Dealkylation of N-Nitrosodibenzylamine by Metalloporphyrin/Oxidant Model Systems for Cytochrome P450Eriko OKOCHI, Masataka MOCHIZUKI1995 Volume 43 Issue 12 Pages 2173-2176
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSN-Nitrosodialkylamines are alkylating carcinogens which are metabolically activated to α-hydroxy nitrosamines through oxidative dealkylation by cytochrome P450. In this study, the dealkylation step in the activation of N-nitrosodibenzylamine (NDBz) was investigated with metalloporphyrin/oxidant model systems under non-aqueous conditions, as biomimetic chemical models of cytochrome P450. In the model systems, NDBz was dealkylated and benzaldehyde was released. The catalytic activity required a porphyrin ring with a central metal that can interact with an oxidant. The oxidative activity of the model varied with the oxidant used in the order of tert-butyl hydroperoxide>cumene hydroperoxide>iodosobenzene, and also with the central metal of porphyrin used in the order of tetraphenylporphyrinatoiron(III) chloride>its manganese derivative. It was confirmed that N-nitro-sodialkylamine undergoes oxidation to α-hydroxy nitrosamine in chemical model systems which are free of protein. These biomimetic models should be useful in elucidating the mechanisms of the metabolism of N-nitrosodialkylamines.View full abstractDownload PDF (621K) -
Tadashige CHIBA, Toshifumi AKIZAWA, Motomi MASTUKAWA, Hidemitsu PAN-HO ...1995 Volume 43 Issue 12 Pages 2177-2181
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWe purified a new type of polyamine neurotoxins called spidamine and joramine in the venom of a spider, Nephila clavata, on a large-scale and confirmed their structures by chemical analysis and NMR spectra. Spidamine was N-(2, 4-dihydroxyphenylacetyl-L-asparaginyl)-N'-(3-aminopropyl-β-alanyl)-1, 5-pentanediamine, whereas joramine was N-(4-hydroxyphenylacetyl-L-asparaginyl)-N'-(3-aminopropyl-β-alanyl)-1, 5-pentanediamine.We also studied the toxins biological activity on glutamatergic transmission using lobster neuromuscular synapses. The blocking activity of both toxins on the excitatory post synaptic potentials (EPSPs) in the lobster muscle was about one tenth time less than JSTX-3, the most potent toxin in the venom of Nephila clavata. Interestingly, spidamine which has 2, 4-dihydroxyphenyl group showed an irreversible block of EPSPs, whereas joramine possessing 4-hydroxyphenyl group had a reversible block.View full abstractDownload PDF (795K) -
Yong HUANG, Hidenao TOYODA, Ichiro KOSHIISHI, Toshihiko TOIDA, Toshio ...1995 Volume 43 Issue 12 Pages 2182-2186
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSDepolymerized holothurian glycosaminoglycan (DHG) produced artificially from sea cucumber has an anticoagulant and antithrombotic activity. In the present study, we attempted to determine the plasma level of DHG using a chemical procedure. A general method for determination of chondroitin sulfates by forming unsaturated disaccharides with chondroitinase digestion was difficult to apply to DHG, because it was resistant to any chondroitinase digestion. We therefore developed a highly sensitive postcolumn HPLC method for determination of intact DHG. DHG was applied to Asahipak NH2P-50, an amino-bonded column, eluted by alkaline solution and then detected with arginine under a strong alkaline condition as a postcolumn reagent. The limit of detection for DHG was 10ng. The present method was applicable to the determination of DHG in plasma after intravenous administration.View full abstractDownload PDF (699K) -
Haruhisa KIZU, Hideki SHIMANA, Tsuyoshi TOMIMORI1995 Volume 43 Issue 12 Pages 2187-2194
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFrom the roots of Clematis stans three new oleanane-type triterpenoid saponins named clemastanoside A, B and C, and two new lignan glycosides named clemastanin A and B, have been isolated together with three known triterpenoid saponins, huzhangoside B, C and D, and three known lignan glycosides, (+)-lariciresinol 4-O-β-D-glucopyranoside, (+)-lariciresinol 4'-O-β-D-glucopyranoside and (+)-pinoresinol 4, 4'-O-bis-β-D-glucopyranoside. In addition, from the leaves, four new oleanane-type triterpenoid saponins, named clemastanoside D, E, F and G, have been isolated together with five known triterpenoid saponins, hederasaponin B, kizutasaponin K12, huzhangoside B, sieboldianoside B and huzhangoside D, and three known flavonoids, isoquercitrin, rutin and quercetin 3-O-β-D-glucuronopyranoside. The structures of the new compounds were elucidated based on chemical and physicochemical evidence as follows : clemastanoside A, 3-O-β-D-ribopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl oleanolic acid 28-O-(4-O-acetyl)-α-L-rhamnopyranosyl-(1→4)-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl ester (terminal rhamnosyl 4-O-acetate of huzhangoside B); clemastanoside B and C, 3-O-β-D-xylopyranosyl- and 3-O-β-D-ribopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→2)-β-D-galactopyranosyl oleanolic acid 28-O-α-L-rhamnopyranosyl-(1→4)-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl ester, respectively; clemastanoside D, 3-O-β-D-ribopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl hederagenin 28-O-β-D-glucopyranosyl ester; clemastanoside E, F and G, terminal rhamnosyl 4-O-, 3-O- and 2-O-acetate of 3-O-β-D-ribopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl hederagenin 28-O-α-L-rhamno-pyranosyl-(1→4)-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl ester, respectively; clemastanin A, (7S, 8R)-3-methoxy-3', 4, 9, 9'-tetrahydroxy-4', 7-epoxy-5', 8-lignan 3'-O-β-D-glucopyranoside; clemastanin B, (+)-lariciresinol 4, 4'-O-bis-β-D-glucopyranoside.View full abstractDownload PDF (1211K) -
Akio HASHIMOTO, Kazuya YAMASAKI, Yoshio KOKUSENYA, Takaaki MIYAMOTO, H ...1995 Volume 43 Issue 12 Pages 2195-2199
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAn analytical method of determining organic acids in animal crude drugs using selective and sensitive postcolumn-pH buffered electroconductivity detection HPLC was established and the organic acid contents in 10 drugs were determined. Nine organic acids : acetic acid, butylic acid, formic acid, isobutylic acid, lactic acid, malic acid, propionic acid, pyroglutamic acid and succinic acid were found. Lactic acid content in Lumbricus varied greatly among the samples from 0.83 to 13.08mg/g, and the contents of acetic acid, butylic acid, isobutylic acid and propionic acid in Cervi Parvum Cornu also showed large variation. Contents of the organic acids in other animal crude drugs did not vary greatly among the samples. These contents were believed to change during the time course of preservation and distribution on the market, so the content in animal crude drugs stored under various conditions, and the appearance, Loss on drying and pH were also studied. No change was observed in any of these factors in any drug stored in tightly closed containers, except for the lactic acid content in Amydae Carapax which showed a slight increase. However, various changes in the factors were observed in all crude drugs stored in 40°C-75% relative humidity (RH) open containers.View full abstractDownload PDF (722K) -
Emi OKUYAMA, Kuniharu SUZUMURA, Mikio YAMAZAKI1995 Volume 43 Issue 12 Pages 2200-2204
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe lignans of (+)-pinoresinol, (+)-epipinoresinol, (+)-lariciresinol and (+)-isolariciresinol together with phenols such as syringaldehyde and 7, 8-dihydro-7-oxy-coniferyl alcohol were isolated from Todopon Puok (Fagraea racemosa JACK ex WALL.), a medicinal plant from Borneo, using a bioassay of the relaxation effect on norepinephrine (NE)-induced contraction in rat aortic strips. The plant extract also exhibited analgesic properties in the acetic acid-induced writhing and tail perssure tests in mice, with the activity being concentrated in the lignan fraction. (+)-Pinoresinol showed analgesic effect on writhing symptoms in mice which were dose-dependent, and produced local anesthesia in guinea pigs.View full abstractDownload PDF (811K) -
Tsuneo HAMAGUCHI, Denji SHINKUMA, Tsuneo TANAKA, You YAMANAKA, Masatos ...1995 Volume 43 Issue 12 Pages 2205-2210
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe bioavabilaility of sulpiride (SP) from a tablet coated with AEA[○!R] (polyvinylacetal diethylaminoacetate), a gastric-fluid-soluble polymer, is very poor in low gastric acidity subjects in the fasting state but improves after food intake. To analyze factors affecting SP bioavailability from AEA[○!R] film-coated tablets (AEA[○!R] tablets), we prepared AEA[○!R] cast film and AEA[○!R] tablets and determined the effects of mechanical destructive force and film coating strength in the gastrointestinal (GI) tract on SP dissolution from the tablets. With the paddle method, rapid SP dissolution occurred at pH 4.0 or below but not at pH 5.0 or above. Using the disintegration test method, dissolution at pH 5.0-5.8 markedly increased as the film coating broke due to an increase in the mechanical destructive force and a change in film coating strength. Microscopic observation of AEA[○!R] film coating at pH 5.0 supported the marked decrease in the cast film strength observed in pH 5.0 medium with an increase in film swelling. Thus, one important factor affecting AEA[○!R] film coating strength is its swelling rate. After food intake, SP bioavailability from AEA[○!R] tablet improves, probably due to increased mechanical destructive force with GI motility and decreased film coating strength in GI fluids with increased film swelling in the pH environment after the meal (pH 5.85). This increased SP dissolution rate from AEA[○!R] tablet leads to enhanced absorption. We concluded that the increase in mechanical destructive force acting on the tablet after food intake is one of the powerful factors leading to improved drug bioavailability.View full abstractDownload PDF (1089K) -
Hiraku IKEDA, Kazumi UCHIYAMA, Kozo TAKAYAMA, Tsuneji NAGAI1995 Volume 43 Issue 12 Pages 2211-2214
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA novel chitosan film was prepared using an electric charge generated on a cast plate and was given characteristic physical properties. Two metal plates were adhered together with Teflon sheet between them. An acetic acid solution of chitosan was poured on the upper plate and a negative charge was supplied galvanostatistically on the metal plate. The solution was dried in order to make the film at room temperature. The cross sectional morphology and the physical properties of tensile strength, breaking elongation and work energy of breaking of the film were compared with those of film prepared without supplying electric potential. The film prepared with an electric charge (VF) was curled gently in water and then gradually flattened. The film prepared without charge (NVF) was curled tightly in water and maintained this shape for a long time. In the cross sectional structure of VF, a line pattern parallel to the film surface was observed microscopically, while a vertical pattern was seen in NVF. The presence of electron on the plate was confirmed by measuring the accumulated volume of negative potential using an oscilloscope connected to the metal plate.View full abstractDownload PDF (1138K) -
Masanao ISHIKAWA, Tadashi NOGUCHI, Junji NIWA, Masayuki KUZUYA1995 Volume 43 Issue 12 Pages 2215-2220
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA controlled-release tablet was obtained by oxygen plasma irradiation on the outer layer of double-compressed tablets prepared from theophylline as a core material and a copolymer of methylmethacrylate (MMA) and benzylmethacrylate (BzMA) as a single wall material, making this possible that polybenzylmethacrylate (PBzMA) has dual intramolecular functions, a plasma degradable main chain and a plasma-cross-linkable benzyl group in the side chain as an effect of plasma irradiation. It was shown that the dissolution profiles can be varied so as to cause release of theophylline at different rates, depending on the set of conditions chosen for tablet manufacture and for plasma operation.View full abstractDownload PDF (904K) -
Shusei ITO, Miki DEMACHI, Yumiko TORIUMI, Takeshi ADACHI, Shigeru ITAI ...1995 Volume 43 Issue 12 Pages 2221-2225
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThree pharmaceutical techniques, i.e., size reduction, solid dispersion and inclusion complexaion, were employed for improvement of the dissolution rate of 4-tert-butyl-2'-carboxymethoxy-4'-(3-methyl-2-butenyloxy)chalcone (SU-740). For the size reduction, pulverization was performed using a jet mill. The solid dispersions of SU-740 were prepared with polyethyleneglycol 6000 (PEG) and polyvinylpyrrolidone K29/32 (PVP). The inclusion complexes of SU-740 with three natural cyclodextrins (α-, β-, γ-CyDs) were prepared by the freeze-drying method, or they were isolated according to the Bs type phase-solubility diagram. The dissolution rates of SU-740 from the PVP coprecipitate and the β-CyD complex were much larger than that of the size-reduced form. On accelerated storage (40°C and 75% relative humidity) for one month, the PVP coprecipitate showed a decrease in the dissolution rate and a change in appearane, whereas the β-CyD complex showed no changes. The present results suggest that inclusion complexation is preferable among the three techniques employed for improving of the dissolution characteristics of SU-740.View full abstractDownload PDF (697K) -
Lee-Yong LIM, Mei-Lin GO1995 Volume 43 Issue 12 Pages 2226-2231
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe influence of the antimalarial agent halofanthrine on the phase transition temperature (Tm) of dipalmitoyl phosphatidyl choline (DPPC) liposomes was investigated by differential scanning calorimetry (DSC). The effects of increasing drug content and varying pH conditions (to give predominantly charged and uncharged states of the drug) on the interaction were considered and compared with those caused by structurally related antimalarials, mefloquine and quinine, under similar conditions. Increasing concentrations of halofanthrine resulted in the gradual disappearance of the original transition endotherm and the appearance of a new drug-induced endotherm at a lower temperature and with a decreased enthalpy of transition. Qualitatively similar observations were made at different pH conditions, suggesting little difference in the mode of interaction of charged and uncharged halofanthrine molecules with DPPC. Increasing concentrations of mefloquine and quinine also caused a decline in Tm but neither drug-induced endotherms was associated with a decreased enthalpy of transition. The results indicate that halofanthrine, unlike mefloquine and quinine, intercalates in the hydrophobic interior of the phospholipid. Its localization among the fatty acid side chains of the phospholipid is possibly related to its greater hydrophobic character compared to mefloquine and quinine. The disruption of phospholipid packing and the consequential effects on membrane permeability and integrity may be relevant to the greater in vitro antimalarial activity of halofanthrine and should be considered in any delibration of its pharmacodynamic action.View full abstractDownload PDF (752K) -
Kazuya ABE, Tetsumi IRIE, Kaneto UEKAMA1995 Volume 43 Issue 12 Pages 2232-2237
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe potential use of three 2-hydroxypropyl ether derivatives of cyclodextrins (HP-α-, HP-β- and HP-γ-CyDs) as biocompatible solubilizers and stabilizers and stabilizers for oleic acid, a lipophilic absorption enhancer, was assessed in the nasal absorption of buserelin, an agonist of luteinizing hormone-releasing hormone, in rats. HP-CyDs increased the aqueous solubility of oleic acid and protected it against oxidation through the formation of inclusion complexes with the efficacy increasing in the order : HP-γ-CyD«HP-α-CyD<HP-β-CyD. The bend structure due to a cis-double bond halfway along the acyl chain of oleic acid provided a better fit into the cavity of HP-β-CyD, in which the double bond appears to be buried, and hence becomes less susceptible to oxidation. The rate and extent of nasal bioavailability of buserelin were remarkably increased by coadministration of oleic acid and HP-β-CyD, compared with the sole use of the enhancer. This enhancement was ascribable to the lowering of both the enzymatic and physical barriers of the nasal epithelium to the peptide, probably through the facilitated transmucosal penetration of oleic acid solubilized in HP-β-CyD.View full abstractDownload PDF (1024K) -
Chisako YAMAGAMI, Yuko MASAKI1995 Volume 43 Issue 12 Pages 2238-2242
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSCapacity factors, k', of monosubstituted thiophenes were obtained by reversed-phase high-performance liquid chromatography, using three kinds of octadecyl silica (ODS) columns and methanol-buffer (pH 7.4) eluents. The relationship between log k' and log P (P : octanol-water partition coefficient) was analyzed in terms of the H-bonding properties of the substituents as a function of the mobile phase composition. Non-hydrogen-bonders and H-acceptors gave a good linear log k'-log P relationship in the eluent containing 50% methanol. As the methanol content was decreased, ester substituents, which are strong H-acceptors, deviated from the regression line. Amide groups, amphiprotic substituents, behaved differently from the non-amphiprotics, as is usually observed. The log kw approach (log kw; the extrapolated log k' value in water) correctly predicted the log P value for non-hydrogen-bonders and weak H-acceptors such as H, alkyls, halogens and OMe, but over-estimated log P for the others. The H-bonding effect of the thiophene ring seems to be small, and hence, the retention behavior of thiophene derivatives is considered to be mainly dependent upon the H-bonding property of substituents.View full abstractDownload PDF (783K) -
Yoshitsugu ARAI, Naoya NAGATA, Yukio MASAKI1995 Volume 43 Issue 12 Pages 2243-2245
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSEnantioselective addition of diethylzinc to benzaldehyde in the presence of easily available, β-hydroxysulfides 1 was investigated. The use of a catalytic amount of 1 gave (S)-1-phenylpropanol in excellent yield with high enantioselectivity, ranging from 85 to 88% ee.View full abstractDownload PDF (495K) -
Seiji MORITA, Kenji OTSUBO, Jun MATSUBARA, Tadaaki OHTANI, Yoshikazu K ...1995 Volume 43 Issue 12 Pages 2246-2252
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSGrepafloxacin (1-cyclopropyl-1, 4-dihydro-6-fluoro-5-methyl-7-(3-methyl-1-piperazinyl)-4-oxo-3-quinoline-carboxylic acid, OPC-17116) (1) exhibits potent and broad-spectrum in vitro and in vivo antibacterial activity. In order to identify the structures of the metabolites of grepafloxacin, 17 possible metabolites were prepared. Among them, 6 compounds were found to be actual metabolites (2a, b, 4a, b and 6a, b) of grepafloxacin in rats, dogs and/or humans. The antibacterial activities of these metabolites were found to be weaker than that of grepafloxacin.View full abstractDownload PDF (923K) -
Huan-ming CHEN, Zhi-da MIN, Munekazu IINUMA, Toshiyuki TANAKA1995 Volume 43 Issue 12 Pages 2253-2255
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new neo-clerodane diterpene, ajugacumbin G, was isolated from Ajuga decumbens THUNB. (Labiatae), and the structure was characterized as 6α-acetoxy-4α, 17-epoxy-18-(3'-hydroxy-2'-methylenebutyryloxy)-neo-cleroda-13-en-15, 16-olide by 1H-and 13C-NMR spectral study and by comparison with the known compounds of ajugacumbins A and B. Reactions to an epoxy moiety of ajugacumbin compounds with halogen acid, HX (X=Cl, Br and I) and with Jones reagent were prepared to supply some samples with different substituents at C-4 for insect antifeedant examination.View full abstractDownload PDF (552K) -
Tsutomu NAKANISHI, Yuka INATOMI, Masatoshi NISHI, Hiroko MURATA, Akira ...1995 Volume 43 Issue 12 Pages 2256-2260
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFrom a whole plant of a fern, Diplazium subsinuatum (WALL. ex HOOK. et GREV.) TAGAWA, two new hopane-triterpene glycosides termed diplaziosides I and II were isolated together with a known hopane-triterpene glycoside named glycoside C (1). The structures of diplaziosides I and II were established as 24-O-[α-L-arabinofuranosyl-(1→2)]-[β-D-glucopyranosyl-(1→6)]-β-D-glucopyranosyl-hopan-28, 22-olide (2) and (22R)-17-hydroxy-24-O-[α-L-arabinofuranosyl-(1→2)]-β-D-glucopyranosyl-28, 22-carbonyloxy-hopan-30-oic acid (3), respectively, in the basis of spectral evidence. In addition, the full 1H- and 13C-NMR assignments for known 1 are also reported for the first time.View full abstractDownload PDF (751K) -
Eijiro HORISAWA, Akio KOMURA, Kazumi DANJO, Akinobu OTSUKA1995 Volume 43 Issue 12 Pages 2261-2263
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe effect of granule strength on the strength of a tablet compressed under a certain force was examined. Crushing strength and diametral compression tests were carried out to assess granule and tablet strength, respectively. When granules were weak, tablet strength increased with granule strength. In some powder/polymer binder systems, a further increase in granule strength led to tablets with maximal strength, which then decreased. It was apparent that hard granules were difficult to deform by compression, and the resulting tablets fractured at the boundary between granules.View full abstractDownload PDF (682K) -
Tadashi MAKINO, Minosuke YAMANAKA, Nobuyuki KITAMORI1995 Volume 43 Issue 12 Pages 2264-2266
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSUsing pregelatinized starch as a binder, fluidized-bed granulation and agitation granulation were attempted to investigate the behavior of starch and to examine its relationship with the resultant tablet properties (hardness and disintegration). The amounts of soluble starch before and after granulation were measured. Also, hardness and the disintegration time of the resultant tablets were measured. In fluidized-bed granulation, the soluble starch content did not change noticeably during granulation, thus exerting no influence on tablet properties. On the other hand, in agitation granulation, the soluble starch content increased, so that the disintegration time of the resultant tablets was prolonged. This may be because the soluble starch increased during agitation granulation due to a large shearing force and inhibited water penetration into the tablet and/or because some changes occurred in the swelling properties of the pregelatinized starch.Therefore, when pregelatinized starch is used as a binder, the fluidized-bed method is recommended to consistently obtain satisfactory tablet properties.View full abstractDownload PDF (589K) -
Shun-ichi HASHIMOTO, Ai SANO, Kazuhiro UMEO, Makoto NAKAJIMA, Shiro IK ...1995 Volume 43 Issue 12 Pages 2267-2269
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA highly efficient 1, 2-trans-β-glycosidation reaction has been developed by using glycopyranosyl diethyl phosphites bearing participating groups such as benzoate, phthalimido, or trichloroethyl carbamate groups at C-2 as glycosyl donors and trimethylsilyl trifluoromethanesulfonate (TMSOTf) as a promoter.View full abstractDownload PDF (490K) -
Yoshiyasu FUKUYAMA, Naomi SHIDA, Mitsuaki KODAMA, Haruyuki CHAKI, Tomo ...1995 Volume 43 Issue 12 Pages 2270-2272
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTricycloillicinone (1), a novel tricyclic prenylated C6-C3 compound, has been isolated as a neurotrophic substance from the woods of Illicium tashiroi and its structure has been elucidated by spectroscopic analyses. Compound 1 could increase ChAT activity in culture of P10 rat septal neurons.View full abstractDownload PDF (420K) -
Akimori WADA, Yukiko TANAKA, Saeko HIRAISHI, Masayoshi ITO1995 Volume 43 Issue 12 Pages 2273-2275
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSStereoselective synthesis of Z, E, E- and E, Z, E-trienylesters was accomplished by the condensation reaction of E, E- and Z, E-dienylketone-tricarbonyliron complexes with lithium enolate of ethyl acetate and subsequent dehydration with thionyl chloride.View full abstractDownload PDF (400K) -
Shinobu HONZAWA, Masahisa NAKADA, Hiroshi KUROSU, Osamu HAZEKI, Toshia ...1995 Volume 43 Issue 12 Pages 2276-2278
Published: December 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTo detect phosphatidylinositol (PI) 3-kinases with high sensitivity, we designed and prepared a radiolabeled derivative of wortmannin (1), a potent inhibitor of PI 3-kinases. The synthesized derivative, 17β-hydroxy-16α-[125I]iodowortmannin (7), showed an IC50 that was 100-fold higher than that of wortmannin itself and which bound to catalytic subunits of PI 3-kinases.View full abstractDownload PDF (482K)
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