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Volume 37, Issue 1
Displaying 1-50 of 60 articles from this issue
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Toshimasa ISHIDA, Kumiko OHNISHI, Mitsunobu DOI, Masatoshi INOUE1989 Volume 37 Issue 1 Pages 1-4
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe stacking interactions of tyrosine methylester (TyrOMe)-guanosine-5'-monophosphate (GMP), TyrOMe-7-methylguanosine-5'-monophosphate (m7GMP), phenylalanine methylester (PheOMe)-GMP and PheOMe-m7GMP pairs in neutral buffer solution have been studied by proton nuclear magnetic resonance (1H-NMR). The H8 proton signal of GMP showed no noticeable temperature dependence, while the signals of other protons showed usual dependences arising from the ring stacking interaction with aromatic amino acids. The results can be interpreted in terms of the intramolecular C-H…O hydrogen bonding and ring stacking. Complex formations in 1 : 1 molar ratio were deduced for all pairs from their Job plots. The association constant for each pair was obtained by analysis of the Scatchard plot. Further, the van't Hoff plot provided thermodynamic parameters of the complex structure. The analyses of these data suggested that albeit the N-quaternization of GMP strengthens the stacking interaction with aromatic amino acid, the bulky methyl group in m7GMP facilitates the dissociation from the amino acid with small environmental change. The possible conformations of GMP and m7GMP in the interaction states are discussed on the basis of the coupling constants.View full abstractDownload PDF (665K) -
Yutaka OKADA, Toyonori TAKEBAYASHI, Sadao SATO1989 Volume 37 Issue 1 Pages 5-8
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThree forms of crystals, the optically active α-form and the optically inactive β-and γ-forms, of 10-bromo-11b-(2-fluorophenyl)-2, 3, 7, 11b-tetrahydrooxazolo[3, 2-d][1, 4]benzodiazepin-6(5H)-one (1) were obtained by different crystallization procedures. The α-form crystal was estimated to be the most stable and the least soluble crystal among them by comparison of the thermodynamic properties of these crystals and the mutual transformations among these crystal forms. X-Ray analyses elucidated that the α-form crystal was an enatiomer, and the β- and γ-form crystals were racemates. Consequently, if a suitable crystallizing condition is selected, it is possible for compound 1 to crystallize as more stable and less soluble crystals of one enantiomer (prior to crystallization of racemates) from methanol solution. These crystal properties of 1 are essential for the second-order asymmetric transformation to occur.View full abstractDownload PDF (707K) -
Katsuyuki KURUMAYA, Masahiro KAJIWARA1989 Volume 37 Issue 1 Pages 9-12
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSProton nuclear magnetic resonance (1H-NMR) signal assignment of cyanocobalamin (vitamin B12) was achieved by the normal two-dimensional NMR method. 1H-1H correlation spectroscopy (COSY) of vitamin B12 showed correlation networks of dimethyl benzimidazole, ribose, isopropanolamine, and corrin ring proton peaks. 1H-1H nuclear Overhauser effect (NOE) spectroscopy (NOESY) allowed assignment of the benzimidazole protons. For assignment of methyl and methylene protons of the corrin ring, 1H-13C COSY measurements were made on 13C-enriched vitamin B12, isolated after feeding experiments with [13CH3]methionine, [2-13C]5-aminolevulinic acid (ALA), and [3-13C]ALA.View full abstractDownload PDF (515K) -
Etsuo OISHI, Akiya YAMADA, Eisaku HAYASHI, Ken-ichi TANJI, Akira MIYAS ...1989 Volume 37 Issue 1 Pages 13-17
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe reaction of 7-(methylsulfonyl)- and 7-chloro-1-penyl-1H-imidazo[4, 5-d]pyridazines (1 and 2) with active methylene compounds (5a-d) or ketones (5e-g) in the presence of sodium hydrige gave the corresponding 7-substituted imidazopyridazines (6a-g). A similar substitution of both 1 and 2 with methoxide ion (8) gave the 7-methoxy-imidazopyridazine (9). However, 1 and 2 reacted with BuNH2 (10) in a different way from the above substitution, resulting in the formation of the corresponding ring fission products of the imidazole portion, 3-substituted 5-amino-4-anilinopyridazines (11 and 12, respectively). The reaction of 1 with alkylmagnesium halides (13a-d) gave the 4, 5- and 2, 3-adducts (III and IV) which were converted into the corresponding 4-alkyl- and 2-alkyl-imidazopyridazines (14a-d and 15a, b) by potassium ferricyanide oxidation. A [4+2] cycloaddition occurred in the reaction of 1 with 1-piperidinocyclopentene (16a) to give the tetrahydroindeno[5, 6-d]imidazoles 17 and 18.View full abstractDownload PDF (747K) -
Koji KUSUMOTO, Tsuneatsu NAGAO, Hikaru OKABE, Tatsuo YAMAUCHI1989 Volume 37 Issue 1 Pages 18-22
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSEight dammarane-type triterpene glycosides named luperosides A-H were isolated from the dried herb of Luffa operculata COGN. (Cucurbitaceae). Their structures were determined on the basis of chemical and spectral evidence as follows. A : a 3, 20-bis-O-β-D-glucopyranoside of (20S)-dammar-24-ene-3β, 7β, 20-triol (Ag). B : a 20-O-β-gentiobioside of Ag. C : a 3-O-β-neohesperidoside-20-O-β-D-glucopyranoside of Ag. D : a 3-O-β-D-glucopyranoside-20-O-β-gentiobioside of Ag. E : a 3-O-β-neohesperidoside-20-O-β-D-xylopyranosyl-(1→6)-β-D-glucopyranoside of Ag. F : a 3-O-β-neohesperidoside-20-O-β-gentiobioside of Ag. G : a 3-O-β-neohesperidoside-20-O-β-gentiobioside of (20S)-dammar-23-ene-3β, 7β, 20, 25-tetraol. H : 3-O-β-neohesperidoside-20-O-β-gentiobiosides of (20S, 24S and R)-dammar-25-ene-3β, 7β, 20, 24-tetraols.View full abstractDownload PDF (915K) -
Masako NAKAGAWA, Hiroshi FUKUSHIMA, Tomohiko KAWATE, Mitsuya HONGU, Te ...1989 Volume 37 Issue 1 Pages 23-32
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSPictet-Spengler reaction of L-tryptophan methyl ester (9) and 6-methoxy-L-tryptophan methyl ester (40) with isovaleraldehyde (10) in methylene chloride in the presence of trifluoroacetic acid gave the cis-tetrahydro-β-carboline (11, 41) as the major isomer. The condensation of 11 and 41 with N-benzyloxycarbonyl-L-proline followed by deprotection gave the cis-cis-pentacycles (27, 44) which contain the parent ring system of fumitremorgins. The trans-cis(28), the cis-trans (29, 30) and the trans-trans (31) pentacycles were similarly prepared. Isopentylation of 27 and 44 gave the Na-isopentyl derivatives (52, 53) accompanied with epimerization at the 12-position. Oxidation of 52 and 53 with dichlorodicyano-p-benzoquinone (DDQ) gave the 12, 13-dehydro derivatives (54, 55) which provided demethoxy-13-epi-tetrahydrofumitremorgin B (57) and 17-bromo-13-epi-tetrahydro-fumitremorgin B (58) by N-bromosuccinimide (NBS)-oxidation in aqueous dimethoxyethane. Debromination of 58 gave 13-epi-tetrahydrofumitremorgin B (59).View full abstractDownload PDF (1555K) -
Fumiko ABE, Tatsuo YAMAUCHI1989 Volume 37 Issue 1 Pages 33-35
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSCortexone and three new bisdesmosidic glycosides of teikagenin were isolated from Trachelospermum liukiuense, together with five glycosides already known in Trachelospermum asiaticum. The new glycosides have D-digitalose linked to the 20-OH as well as to the 3-OH.View full abstractDownload PDF (493K) -
Mitsuaki WATANABE, Mutsuhiro DATE, Masao TSUKAZAKI, Sunao FURUKAWA1989 Volume 37 Issue 1 Pages 36-41
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSVarious methoxy-substituted thioxanthen-9-one derivatives were regioselectively synthesized by a one-pot condensation of S-lithiated thiosalicylic ester or amides, obtained via directed lithiation of tertiary benzamides, with benzynes. Similarly, the synthesis of selenoxanthen-9-ones was achieved.View full abstractDownload PDF (850K) -
Chun-Jie SHAO, Ryoji KASAI, Jing-Da XU, Osamu TANAKA1989 Volume 37 Issue 1 Pages 42-45
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFurther investigation of the chemical constituents of the leaves of Acanthopanax senticosus HARMS. resulted in the isolation of five new triterpenoid saponins, named ciwujianosides A1 (1), A2 (2), A3 (3), D3(4) and A4 (5). The structures of these saponins were elucidated as follows : 1, 3-O-β-glucopyranosyl-(1→2)-α-arabinopyranosyloleanolic acid 28-O-α-rhamnopyranosyl-(1→4)-β-glucopyranosyl-(1→6)-β-glucopyranosyl ester; 2, 3-O-β-glucopyranosyl-(1→2)-α-arabinopyranosyl-30-norolean-12, 20(29)-dien-28-oic acid 28-O-α-rhamnopyranosyl-(1→4)-β-glucopyranosyl-(1→6)-β-glucopyranosyl ester; 3, 3-O-α-rhamnopyranosyl-(1→2)-α-arabinopyranosylmesembryanthemoidigenic acid 28-O-α-rhamnopyranosyl-(1→4)-β-glucopyranosyl-(1→6)-β-glucopyranosyl ester; 4, 3-O-α-arabinopyranosylmesembryanthemoidigenic acid 28-O-α-rhamnopyranosyl-(1→4)-6-O-acetyl-β-glucopyranosyl-(1→6)-β-glucopyranosyl ester; 5, 3-O-β-glucopyranosyl-(1→2)-α-arabinopyranosylmesembryanthemoidigenic acid 28-O-α-rhamnopyranosyl-(1→4)-6-O-acetyl-β-glucopyranosyl-(1→6)-β-glucopyanosyl ester.View full abstractDownload PDF (563K) -
Satoshi TSUBOI, Yoshio OKADA1989 Volume 37 Issue 1 Pages 46-49
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS6-Chloro-2-pyridyl esters (OPyCl) of Nα-benzyloxycarbonyl and tert-butyloxycarbonylamino acids were synthesized by the N, N'-dicyclohexylcarbodiimide (DCC) method from the acids and 6-chloro-2-hydroxypyridine in dimethylformamide (DMF). The reactivity of the 6-chloro-2-pyridylester with amino group is much higher than that of the corresponding 2-pyridyl ester (OPy) and p-nitrophenyl esters (ONp) in dioxane and DMF, and a peptide bond is formed without acylation at the side chain hydroxyl group of amino acids. Z-Asp(OBzl)-OPyCl reacted with amino acid methyl esters in dioxane to give the corresponding dipeptide without any detectable aspartimide formation.View full abstractDownload PDF (636K) -
Gen-ichiro NONAKA, Makoto ISHIMATSU, Masayuki AGETA, Itsuo NISHIOKA1989 Volume 37 Issue 1 Pages 50-53
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSCercidinins A(1) and B(2) and cuspinin (3), unusual ellagitannins having an R-hexahydroxydiphenoyl ester group at the glucose 2, 3-positions, have been isolated from the bark of Cercidiphyllum japonicum (Cercidiphyllaceae) and the leaves of Castanopsis cuspidata var. sieboldii (Fagaceae). On the basis of chemical and spectroscopic evidence, their structures were established as 1, 4, 6-tri-O-galloyl-2, 3-(R)-hexahydroxydiphenoyl-β-D-glucose(1), 4, 6-di-O-gallolyl-2, 3-(R)-hexahydroxydiphenoyl-D-glucose (2) and 1-O-galloyl-2, 3-(R);4, 6-(S)-hexahydroxydiphenoyl-β-D-glucose (3). The co-occurrence of 3 with the atropisomeric S-hexahydroxydiphenoyl derivative suggests the non-specificity of the enzyme which converts gallic acid to hexahydroxydiphenoic acid.View full abstractDownload PDF (657K) -
Tadahiro TAKEDA, Masahiko SAWAKI, Yukio OGIHARA, Seiichi SHIBATA1989 Volume 37 Issue 1 Pages 54-56
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSNephritogenoside is a minor component of the basement membrane of normal animals (including humans). It is a glycopeptide with the ability to induce chronic progressive glomerulonephritis (end stage kidney) when administered as a single footpad injection, and contains a novel carbohydrate-peptide linkage. The total chemical structure was investigated. It was revealed that nephritogenoside is a simple glycopeptide composed of three glucose residues [α-Glc-(1→6)-β-Glc(1→6)-Glc] and twenty-one amino acids[1Asn-Pro-Leu-Phe-5Gly-Ile-Ala-Gly-Glu-10Asp-Gly-Pro-Thr-Gly-15Pro-Ser-Gly-Ile-Val-20Gly-21Gln], and that the glucose residues are linked α-N-glycosidically to the N-terminal amino acid.View full abstractDownload PDF (528K) -
Isao KITAGAWA, Motomasa KOBAYASHI, Manabu HORI, Yoshimasa KYOGOKU1989 Volume 37 Issue 1 Pages 61-67
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA full account of the structure elucidation of four lanostane-type triterpene oligoglycosides, bivittosides A(6), B(8), C(9), and D (10), is presented. Bivittosides were isolated from body-walls and Cuvierian tubules of the Okinawan sea cucumber Bohadschia bivittata MITSUKURI, and among these four oligoglycosides, bivittoside D(10) showed significant antifungal activities. Acidic hydrolysis of bivittosides A(6), B(8), and D(10) provided three artifact sapogenols, among which a homoannular-dienic sapogenol named preseychellogenin (4), exhibiting characteristically red-shifted ultraviolet and circular dichroism spectra, was identified as the monoacetate (4a).View full abstractDownload PDF (1106K) -
Mariko TANOGUCHI, Tatsuhiko KASHIMA, Hideyuki SAIKA, Taishi INOUE, Mas ...1989 Volume 37 Issue 1 Pages 68-72
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo new lignans, hernolactone (1) and fernandin (2), isolated from the seeds of Hernandia ovigera L. were synthesized in recemic forms. Firstly, (±)-1 was obtained by utilizing the conjugate addition reaction of 4 with butenolide followed by alkylation with trimethoxybenzyl bromide and subsequent removal of the protecting groups. Synthesis of 2 was pursued using the corresponding 4-phenyl-1, 2-dihydronaphthalene lactone(18). The cleavage of the lactone moiety of 18 afforded an unsaturated hydroxy acid (22). Subsequent hydrogenation of 22 followed by acidification with concetrated hydrochloric acid gave isopicrobernanadin (21), leaving the 2, 3-trans, 3, 4-cis hydroxy acid (23), which was lactonized by means of N, N-dicyclohexylcarbodiimide to afford (±)-2.View full abstractDownload PDF (824K) -
Ko NAKAMURA, Kunihiko HIGASHIURA, Kazuharu IENAGA1989 Volume 37 Issue 1 Pages 73-76
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIf oligopeptides contain a free and acidic α-amino acid at the N-terminal, the B/E linked scan sputtered ion mass spectrometry (SIMS) technique is useful, without derivatization, as a general method not only to distinguish each pair of α- and ω-isomers but also to elucidate some of their structures. Ten pairs of such glutamyl oligopeptides (1-10, 11-20) and five pairs of aspartyl dipeptides (28-37) were examined in order to prove the usefulness and generality of the technique. γ-Linkage of the terminal acidic amino acid in naturally occurring norophthalmic acid (17) and glutathione (21) could be identified easily by using this method. Spectra of a pair of acetylated glutamyl dipeptides (21, 23), and two pairs of esters (24-27) of glutamic acid were also measured for comparison.View full abstractDownload PDF (568K) -
Fumio HASHIMOTO, Gen-ichiro NONAKA, Itsuo NISHIOKA1989 Volume 37 Issue 1 Pages 77-85
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThree novel chalcan-flavan dimers, assamicains A (1), B (2) and C (3), and a new flavan-3-ol (14) and proanthocyanidins (19, 20) have been isolated, together with the known flavan-3-ols (4-13), proanthocyanidins(15-18, 21), theasinensins (22-24) and hydrolyzable tannins (25, 26), from the fresh leaves of Camellia sinensis var. assamica (Camelliaceae), and their structures have been established on the basis of spectroscopic evidence in conjunction with thiolytic degradation and enzymatic hydrolysis.View full abstractDownload PDF (991K) -
Kenji AKAHANE, Yasuo NAGANO, Hideaki UMEYAMA1989 Volume 37 Issue 1 Pages 86-92
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo empirical indices accounting for the hydrophobic interaction are described. The first index is a "hydrophobic field-effect (Hf) index, "which indicates the hydrophobic nature of the binding site of a host molecule such as an enzyme, and the second index is a "hydrophobic correlation (Hc) index", which indicates the hydrophobic correspondency between a host molecule and its guest molecule such as a ligand. Furthermore, a method to calculate the surface area of a molecule is described, in which the molecular surface is treated as a set of area-preserving spherical triangles. The hydrophobic effects on the interaction between papain and its inhibitor benzyloxycarbonyl-L-phenylalanyl-L-alanyl-methylene (Z-Phe-Ala-CH2-), which is covalently bound to catalytic Cys Sγ of the enzyme, were investigated by using these indices. It is quantitatively shown that the binding sites interacting with the benzene rings of P2 Phe and P3 Z are more hydrophobic, while the site of the carbonyl group of P1 Ala is more hydrophilic. The substrate specificity of papain can be explained in part by these indices. Both the Hc and Hf indices are visualized by using computer graphics. These indices would be useful as quantitative structure-activity relationship (QSAR) parameters.View full abstractDownload PDF (1359K) -
Teruyuki MIYAMOTO, Jun-ichi MATSUMOTO1989 Volume 37 Issue 1 Pages 93-99
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSChemical modification of cinoxacin was studied with the aim of improving its antibacterial activity and spectrum. Alkylation of ethyl 6, 7, 8-trifluoro- and 6, 7-difluoro-4-hydroxycinnoline-3-carboxylates (1 and 7) with alkyl iodide or dialkyl sulfate gave ethyl 1-alkyl-6, 7, 8-trifluoro- and 6, 7-difluoro-1, 4-dihydro-4-oxocinoline-3-carboxylates (2 and 8), together with the isomeric anhydro-bases 3 and 9 of 2-alkyl-3-ethoxycarbonyl-6, 7, 8-trifluoro- and 6, 7-difluoro-4-hydroxycinnolinium hydroxides, respectively. Acid-catalyzed hydrolysis of the 1-alkyl derivatives 2 and 8 gave the corresponding carboxylic acids 4 and 10. The same treatment of 3 and 9, accompanied with decarboxylation of the inner salts 5 and 11, afforded the anhydro-bases 6 and 12 of 2-alkyl-4-hydroxycinnolinium hydroxides, respectively. Displacement reactions of 4 and 10 with nucleophiles such as amine, alkoxide and thiolate gave 7-substituted 1-alkyl-6, 8-difluoro- and 6-fluoro-1, 4-dihydro-4-oxocinnoline-3-carboxylic acids (13 and 17-35). Antibacterial activities of these compounds were evaluated and compared with those of cinoxacin and norfloxacin. Some compounds showed a broader spectrum and more potent activity than cinoxacin, but were considerably inferior in activity to norfloxacin.View full abstractDownload PDF (961K) -
Yoshinori NISHIKAWA, Tokuhiko SHINDO, Katsumi ISHI, Hideo NAKAMURA, Ta ...1989 Volume 37 Issue 1 Pages 100-105
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new series of acrylamide derivatives (7-10) were synthesized. Antiallergic activity of these compounds was evaluated and their structure-activity relationships were examined. Compounds 10d, N[4-(4-diphenylmethyl-1-piperazinyl)buthyl]3-(3-pyridyl)acrylamide, showed antiallergic activity equivalent or superior to that of ketotifen in the rat passive cutaneous anaphylaxis (PCA) test by oral administration. Compound 10d, unlike ketotifen, had more potent in vitro 5-lipoxygenase inhibitory activity than caffeic acid, whereas its in vitro antihistamine activity was weaker than that of ketotifen. In addition, its inhibitory activity against histamine release from rat mast cells was approximately two-thirds as potent as that of disodium cromoglycate (DSCG). Compound 10d is a promising agent for treating a variety of allergic diseases.View full abstractDownload PDF (766K) -
Yoshiaki YOSHIKUNI, Yohji EZURE, Takashi SETO, Kazuya MORI, Masayoshi ...1989 Volume 37 Issue 1 Pages 106-109
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSVarious N-substituted derivatives of 4-O-α-D-glucopyranosylmoranoline have been synthesized, and their inhibitory activities against rabbit sucrase and maltase have been measured, as well as their effects on postprandial hyperglycemia in the sucrose-loaded rat, 4-O-α-D-Glucopyranosylmoranoline was also shown to have potent hypoglycemic activity in starch-loaded dogs.View full abstractDownload PDF (660K) -
Katsuhiko HINO, Katsuyoshi KAWASHIMA, Makoto OKA, Yasutaka NAGAI, Hito ...1989 Volume 37 Issue 1 Pages 110-115
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe synthesis of a novel class of antiulcer agents, the substituted 4-phenyl-2-(1-piperazinyl)quinolines, and their pharmacological activities (inhibitory effects on hypothermia induced by reserpine and on gastric ulcers induced by stress or ethanol) are described. These compounds can be classified into three groups (a group predominantly effective on the stress-induced ulcer, one effective on both the stress- and ethanol-induced ulcers, and one selectively effective on the ethanol-induced ulcer), with regard to antiulcer activity. The inhibitory effect on stress-induced ulcer was found to be in close relation to the antagonism of hypothermia. The structure-activity relationships in these compounds are described. Among the compounds, 2-(4-ethyl-1-piperazinyl)-4-phenylquinoline dimaleate (9, AS-2646) showed a potent inhibition of stress-induced ulcer and gastric acid secretion, possively through action on the central nervous system, and it was selected for clinical evaluation.View full abstractDownload PDF (847K) -
Kimiko NAKANO, Kotaro MURAKAMI, Yoshihisa TAKAISHI, Toshiaki TOMIMATSU ...1989 Volume 37 Issue 1 Pages 116-118
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe constituents of the fresh whole plants of Heloniopsis orientalis (THUNB.) C. TANAKA (Liliaceae) were investigated and five steroidal components were obtained. Their chemical structures were characterized as dioscin (1), pennogenin3-O-β-chacotrioside(T-c)(2), pregnadienolone 3-O-β-chacotrioside(P-d)(3), 26-O-β-D-glucopyranosyl17-dehydrokryptoenin 3-O-β-chacotrioside (4) and 12-O-β-D-galactopyranosyl helonigenin 3-O-β-D-allomethylopyranosyl-(1→5)-β-D-apiofuranoside (5).View full abstractDownload PDF (564K) -
Fujio IMAI, Kikuo ITOH, Noriko KISHIBUCHI, Takeshi KINOSHITA, Ushio SA ...1989 Volume 37 Issue 1 Pages 119-123
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA mixture of fatty acid esters (Va) of murrangatin was obtained from the root bark of Murraya paniculata (Rutaceae) collected in Indonesia together with eleven known constituents of chemotaxonomical significance, and their structures were characterized on the basis of spectroscopical and chemical data. Neither prenylindoles nor biogenetically related compounds, found in Formosan M. paniculata, were detected.View full abstractDownload PDF (724K) -
Kiyoshi IWAGOE, Takashi KAKAE, Tenji KONISHI, Shiu KIYOSAWA, Yasuhiro ...1989 Volume 37 Issue 1 Pages 124-128
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThree new bi-2-(2-phenylethyl)chromones, tentatively named AH12, AH13and AH14, were isolated from agalwood "Jinko" along with AH10, AH11 and AH15. The structures of AH12 and AH13 were elucidated as (5S, 6R, 7R, 8S)-2-(2-phenyletyl)-5, 6, 7-trihydroxy-5, 6, 7, 8-tetrahydro-8-[2-(2-phenylethyl)-7-methoxychromonyl-6-oxy]chromone and its de-7-methoxylate, respectively. AH14 was concluded to be (5S, 6S, 7S, 8R)-2-(2-phenylethyl)-6, 7, 8-trihydroxy-5, 6, 7, 8-tetrahydro-5-[2-(2-phenylethyl)chromonyl-6-oxy]chromone. Elucidation of 5, 6' and 8, 6'-ether bonding in bi-2-(2-phenylethyl)chromones was done by detailed analyses of the proton and carbon-13 nuclear magnetic resonance (1H and 13C-NMR) spectra, and measuring nuclear Overhauser effect (NOE) difference values.View full abstractDownload PDF (721K) -
Makoto ISHIMATSU, Takashi TANAKA, Gen-ichiro NONAKA, Itsuo NISHIOKA, M ...1989 Volume 37 Issue 1 Pages 129-134
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe diastereoisomeric ellagitannins, nupharins A (1) and B (11), and related compounds (8, 10, and 15), have been isolated from the rhizomes of Nuphar japonicum DC. (Nymphaeaceae). One the basis of physicochemical evidence, their structures were characterized as 1, 2, 4-tri-O-galloyl-(1) and 1, 2-di-O-galloyl-3, 6-(S)-hexahydroxydiphenoyl-α-D-glucopyranoses (8), 2-O-galloyl-3, 6-(S)-hexahydroxydiphenoyl-D-glucose (10), and 1, 2, 4-tri-O-galloyl- (11) and 1, 2-di-O-galloyl-(R)-hexahydroxydiphenoyl-α-D-glucopyranoses (15).View full abstractDownload PDF (834K) -
Masaaki KUWABARA, Fumiaki KAWANISHI, Takeya KOMIYA, Haruji OSHIO1989 Volume 37 Issue 1 Pages 135-139
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS6"-Malonylginsenosides-Rb1, (6), -Rd (7) and 6"-malonylgypenoside V (8) were isolated from the fresh leaves of Gynostemma pentaphyllum selected from wild plants. It was found that the saponin content of dry leaves was markedly reduced because of decomposition of saponins, by intracellular glycosidases.View full abstractDownload PDF (748K) -
Keiko WATANABE, Masataka ISHIBASHI, Noriaki HARIMA, Stefan KROLIK1989 Volume 37 Issue 1 Pages 140-144
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSGas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS) properties of 11-dehydrothromboxane B2 (11-dehydro-TXB2) methyl ester-11-n-propylamide-15-diethylhydrogensilyl (DEHS)-9, 12-cyclic diethylsilylene (DES) derivatives were studied. The methylene unit (MU) value of this derivative was 35.17, being 5.7 higher than that of the 11-dehydro-TXB2 methyl ester-bis-trimethylsilyl ether derivative. The mass spectrum of this derivative was characterized by the ion at m-z 368, which consisted of the fragment of the DES ring and the α-side chain. The major fragmentations were directed by fission of the DES group to give silicon atom-containing ions, inducating that the DES ring takes a leading part in the formation of characteristic ions. Other fragmentations common to the prostanoid derivatives were losses of an ethyl radical from the DAHS or DES group, a C5H11 hydrocarbon fragment and diethylhydrogensilanol. The fragmentation mechanisms are briefly discussed.View full abstractDownload PDF (662K) -
Eisuke SATO, Satoko NISHIKAWA, Yuichi KANAOKA1989 Volume 37 Issue 1 Pages 145-147
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAs a sensitive fluorometric assay for the activity of angiotensin converting enzyme, bimane-peptides containing tryptophan, i.e., 1, 7-dioxo-2, 5, 6-trimethyl-1H, 7H, pyrazolo[1, 2-α]pyrazol-3-yl-methylthiomethylcarbonyl-glycyl (or L-phenylalanyl)-L-tryptophyl-L-leucine (or L-proline), were synthesized and shown to be potent fluorogenic substrates for the micro-determination of angiotensin I converting enzyme activity.View full abstractDownload PDF (513K) -
Shizuo NAKAJIN, Shuji OHNO, Masatada AOKI, Masato SHINODA1989 Volume 37 Issue 1 Pages 148-150
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe cofactor requirement of purified 20β-hydroxysteroid dehydrogenase from cytosol fraction of neonatal pig testis, in the reduction of 17α-hydroxyprogesterone was investigated. The enzyme required β-nicotinamide adenine dinucleotide phosphate, reduced form (β-NADPH) as the preferred cofactor, with an apparent Km value of 17 μM. Furthermore, α-nicotinamide adenine dinucleotide phosphate, reduced form (α-NADPH), β-3'-NADPH and B-nicotinamide adenine dinucleotide (β-NADH) were also utilized as hydrogen donors in the reduction at relatively high concentration with apparent Km values of 85.2μM, 179.2μM and 1.00mM, respectively. The optimum pH was 5.5 when β-NADPH was used as the cofactor, while it was 6.0 when β-NADH was used. The hydrogen transfer from the β-NADPH to the product, 17α, 20β-dihydroxypregn-4-en-3-one catalyzed by 20β-hydroxysteroid dehydrogenase was stereospecific, and the 4-pro-S-hydrogen of the nicotinamide moiety was transferred to the product.View full abstractDownload PDF (547K) -
Francis COMBY, Anne-Catherine JAMBUT-ABSIL, Jacques BUXERAUD, Claude R ...1989 Volume 37 Issue 1 Pages 151-154
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSMolecular interactions between iodine and various neuroleptics were investigated by UV/Vis spectroscopy. Iodine was found to form charge transfer complexes in a 1 : 1 stoichiometry and of n-σ type with these molecules. The values of the formation constants Kc of these iodinated complexes indicate a strong donor-acceptor interaction. These drugs can therefore be expected to interfere with thyroid metabolism.View full abstractDownload PDF (528K) -
Kiyoshi SAKAI, Yukiko SAITOH, Chie IKAWA, Toshiaki NISHIHATA1989 Volume 37 Issue 1 Pages 155-159
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSOral administration of ethanol to rats at a dose of 3g/kg decreased alcohol dehydrogenase (ADH) activity and metabolism of lactate to pyruvate in the liver. The effects of water extracts of Aloe and some other herbs on blood ethanol concentration and on ADH activity in liver cytosol were examined. The water extracts of these herbs caused a faster elimination of ethanol from blood or normal rats when administerd orally 30 min before oral administration of ethanol. The rapid elimination of ethanol seems to be due to a protection of ADH activity and the suply of nicotinamide dinucleotide, both of which are reduced by high ethanol concentration. The effects of ethanol in decreasing the enzyme activities relating to its own metabolism occur when high concentrations of ethanol pass through the liver, and thus may primarily appear during the absorption of alcohol from the gastrointestinal tract, when portal concentrations of ethanol are vary high.View full abstractDownload PDF (797K) -
Kozo TAKAYAMA, Tsuneji NAGAI1989 Volume 37 Issue 1 Pages 160-167
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA modified optimization technique, based on the response surface methodology, was developed for selecting pharmaceutical formulations. In general optimization methods, it is difficult to insure that the optimum formulation is strictly obtainable. Thus, the combined use of random number techniques and Andrews' plots with general optimization methods was investigated for seeking the optimum formulation. The method developed in this study was applied to the optimization of a sustained-release formulation based on the interpolymer complex of polyvinylpyrrolidone with carboxyvinyl polymer. Indomethacin was selected as a model drug for which sustained-release formulations are desirable. Experimental results obtained for the optimum formulation agreed well with the predictions, indicating the usefulness of this approach.View full abstractDownload PDF (1118K) -
Takashi TAN, Masashi KURAMOTO, Terutaka TAKAHASHI, Hideo NAKAMURA, Yut ...1989 Volume 37 Issue 1 Pages 168-173
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe absorption characteristics of morphine were investigated by using rat gastrointestine. Absorption and transport experiments were carried out by the in situ loop and the in vitro everted sac methods, respectively. Brush border membrane vesicles (BBMVs) were used for uptake experiments. Morphine and its metabolites, morphine-3-glucoronide (M-3-G), and morphine-6-glucuronide (M-6-G), in biological samples were simultaneously determined by high-performance liquid chromatography (HPLC) with ultraviolet (UV) detection and electrochemical detection.In the in situ loop method, morphine was well absorbed in the order of jejunal site > duodenal site > ileal site > middle intestinal site > rectal site, but it was poorly absorbed from the stomach. In each of the everted duodenal and jejunal sacs, 2, 4-dinitrophenol, a metabolic inhibitor, inhibited the transport of morphine from the mucosal side to the serosal side. Further, HgCl2 pretreatment reduced the absorption of morphine from the duodenal andr the jejunal loops.The initial uptake of morphine by BBMVs was stimulated in the presence of an H+ gradient (inner pH 7.5 and outer pH 5.0) and an overshoot phenomenon was observed. The initial uptake showed concentration dependence, i.e., it was saturable.Results obtained in this study indicate that carrier-mediated transport stimulated by the H+ gradient is partly involved in the duodeno-jejunal absorption of morphine, although morphine is passively absorbed from other sites.View full abstractDownload PDF (918K) -
Takashi FUJIMOTO, Riichi TAWA, Shingo HIROSE1989 Volume 37 Issue 1 Pages 174-176
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAbout 20 μl of whole blood obtained by venipuncture from rat tail vein was spotted onto a filter paper and the blood spot was punched out (5 mm diameter). Sisomicin (SISO) in the dried blood spot (DBS) was extracted effectively into 0.5M Na2HPO4 solution by ultrasonication and determined by reversed-phase high-performance liquid chromatography with pre-column derivatization using o-phthalaldehyde and β-mercaptopropionic acid. This method could be used for the pre-clinical study of SISO blood levels of a number of mice or rats without killing. The results were identical with those for SISO in serum, if corrected for hematocrit values, and were used for the calculation of pharmacokinetic parameters for individual rats. The detection limit of SISO in DBS (10.1 μl of whole blood) was 1.0 μg per ml of whole blood.View full abstractDownload PDF (526K) -
Takabumi NAGAI, Masayoshi HAMA, Masahiko YOSHIOKA, Mariko YUDA, Noriko ...1989 Volume 37 Issue 1 Pages 177-183
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS1-(Trifluoromethyl)homoallyl alcohols, which were obtained by the ene reaction of trifluoromethyl ketones with olefins, were dehydrated with POCl3-pyridine or other acyl halide-organic base mixtures to trifluoromethylated dienes. Dehydration of the homoallyl alcohols from hexafluoroacetone afforded only one kind of products, while those from other trifluoromethyl ketones were dehydrated to the E-isomers of conjugated dienes as major products with small amounts of regio- and stereoisomers. Treatment of the homoallyl alcohols from inner olefins with phosphorus oxychloride in pyridine gave the conjugated dienes stereoselectively. The saturated (trifluoromethyl)-carbinols which were obtained by hydrogenation of trifluoromethylated homoallyl alcohols were very difficult to dehydrate. This fact shows that the formation of a conjugated double bond or the presence of an allylic hydrogen facilitates the dehydration.View full abstractDownload PDF (1162K) -
Tsuyoshi SATOH, Atsushi SUGIMOTO, Koji YAMAKAWA1989 Volume 37 Issue 1 Pages 184-186
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSOxidation of the chlorohydrins derived from 1-chloroalkyl phenyl sulfoxides and aldehydes gave the β-keto sulfoxides having an alkyl group and a chlorine atom on the α-carbon. The β-keto sulfoxides were reduced with diisobutylaluminum hydride to afford the syn-chlorohydrins as sole products, which were converted to the (E)-α, β-epoxy sulfoxides.View full abstractDownload PDF (481K) -
Ken-ichi TANJI, Susumu SATO, Akira MIYASHITA, Etsuo OISHI, Takeo HIGAS ...1989 Volume 37 Issue 1 Pages 187-189
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS1-Benzoyl-1, 6-dihydro-9-phenyl-9H-purine-6-carbonitrile(1, 9-phenylpurine Reissert compound) was hydrolyzed in an acid medium to give the ring fission product of the pyrimidine ring (3, 4). Alkaline hydrolysis of 1 gave 9-phenyl-9H-purine (2) and benzoic acid (5). The anion of 1 generated from 1 and sodium hydride in tetrahydrofuran underwent aromatization, resulting in the formation of 9-phenyl-9H-purine-6-carbonitrile (6) together with 2. The reaction of 1 with aromatic aldehydes in the presence of sodium hydride proceeded to give the 6-purinylmethyl benzoates (8a-c), together with 2 and 9. On the other hand, the reaction of 1 with 2, 4-dinitrochlorobenzene in the presence of sodium hydride failed to give the corresponding 6-arylpurine, and the aromatization product 6 was obtained.View full abstractDownload PDF (506K) -
Katsuhiko HINO, Katsuyoshi KAWASHIMA, Makoto OKA, Hitoshi UNO, Jun-ich ...1989 Volume 37 Issue 1 Pages 190-192
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe metabolites 3 and 4 of 2-(4-ethyl-1-piperazinyl)-4-phenylquinoline dimaleate (AS-2646, 1), a candidate as a gastric antisecretory and antiulcer drug, were synthesized to confirm thr proposed structures. The effects of the metabolites 2-4 on ulcer induced by stress were determined.View full abstractDownload PDF (489K) -
Yoshihiro KANO, Ken-ichi KOMATSU, Ken-ichi SAITO, Hideo BANDO, Tetsuro ...1989 Volume 37 Issue 1 Pages 193-194
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new polyacetylene compound (4), (6E, 12E)-tetradecadiene-8, 10-diyne-1, 3-diol diacetate has been isolated along with (4E, 6E, 12E)-tetradecatriene-8, 10-diyne-1, 3-diol diacetate and atractylenolide I from Atractylodes Rhizome. The structure of 4 was determined on the basis of its spectral data and chemical reaction.View full abstractDownload PDF (396K) -
Mizuo MIZUNO, Koh-ichi TAMURA, Toshiyuki TANAKA, Munekazu IINUMA1989 Volume 37 Issue 1 Pages 195-196
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThree new flavonoids isolated from the roots of Euchresta japonica, designated as euchrenones a4, b4 and b5, were identified as 5, 7-dihydroxy-6, 8-di(γ, γ-dimethylallyl)-[6'''', 6''''-dimethylpyrano(2'''', 3'''' : 4', 3')]flavanone, 5, 7-dihydroxy-2'-methyoxy-4', 5'-methylenedioxy-6, 8-di(γ, γ-dimethylallyl)isoflavone and 5, 7, 2'-trihydroxy-4', 5'-methylene-dioxy-6, 8-di(γ, γ-dimethylallyl)isoflavone by means of spectral analysis.View full abstractDownload PDF (409K) -
Daisuke TESHIMA, Kayo IKEDA, Koichiro SHIMOMURA, Toshinobu AOYAMA1989 Volume 37 Issue 1 Pages 197-199
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe emetic principles, emetine (EM) and cephaeline (CP), in ipecac syrup were simultaneously analyzed after direct dilution with distillede water, without any other pretreatment. The separation of EM and CP was accomplished by high-performance liquid chromatography (HPLC) with a reversed-phase column, and peaks corresponding to EM and CP were examined by electron ionization-mass spectroscopy (El-MS). We decribe the conditions for the quantitative analysis of EM and CP by HPLC.View full abstractDownload PDF (434K) -
Miyuki TAKAYANAGI, Shoji GOTO, Yukio KOKUBO, Makoto SUZUKI, Tamotsu YA ...1989 Volume 37 Issue 1 Pages 200-201
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA method was developed for the measurement of acetaldehyde in human blood by high-performance liquid chromatography (HPLC). The method was based on a pre-column reaction; a fluorescent substance was formed by a coupling reaction between 2mol of cyclohexan-1, 3-dione and 1 mol of acetaldehyde with ammonium acetate. The coupling compound was analyzed by HPLC and the concentration of acetaldehyde was obtained from the calibration curve drawn from the results using standard solutions. The determination was sensitive and reproducible with a range of 0.2-10 μM and a precision (coefficient of variation) of 2.43%.View full abstractDownload PDF (396K) -
Masako TOKUWAME, Miyuki TAKAYANAGI, Tamotsu YASHIRO1989 Volume 37 Issue 1 Pages 202-203
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSN, N'-Diphenylethylenediamine (DPED) was found to be a useful hydrogen donor for the determination of hydrogen peroxide in the presence of peroxidase. Pigments formed by this reaction had a peak absorbance at 450nm and had relatively high absorptivity; the measurable range of hydrogen peroxide was between 0.15 and 10 μM. The intra-assay and inter-assay precisions (coefficients of variation) of hydrogen peroxide determination were below 0.99 and 1.86%, respectively. The recovery was 97.2-102.8% (n=10).View full abstractDownload PDF (388K) -
Shigeki FUKASAWA, Masaru MIYAHARA, Masayo HOSODA, Munetsugu KURATA1989 Volume 37 Issue 1 Pages 204-205
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA proteinase from the culture supernatant of marine luminous bacterium, Vibrio harveyi strain FLN-77, was purified. The purified enzyme had a molecular weight of 62000. The enzyme was most active at pH 8.0 and 55°C, and was stable below 45°C. The enzyme activity was completely inhibited by ethylendiaminetetra acetic acid, orthophenanthroline and phosphoramidon. Metal ions such as Cu2+, Hg2+ and Ni2+ also inhibited the activity. These results indicated that this enzyme is a metal-chelator-sensitive, alkaline proteinase.View full abstractDownload PDF (438K) -
Yumiko SATOH, Mikio YAMAZAKI1989 Volume 37 Issue 1 Pages 206-207
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe compound tentatively named TL-1 was isolated from Talaromyced luteus as a metabolite having a monoamine oxidase (MAO) inhibitory potency. TL-1 showed mixed-type inhibition of MAO in mouse liver when kynuramine was used as a substrate, and the IC50 was 6.6 μM. The inhibition constants (Ki) for MAO-A and -B in mouse liver were 39.9 and 7.85 μM, respectively. On the other hand, the Ki values for MAO-A and -B in mouse brain were 74.0 and 0.71 μM, respectively. despite the marked structural resemblance between TL-1 and 7-episclerotiorin, the latter compound had little inhibitory effect on MAO.View full abstractDownload PDF (394K) -
Shozo MIYAZAKI, Chizuko YOKOUCHI, Masahiko TAKEDA1989 Volume 37 Issue 1 Pages 208-210
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA polymeric system capable of delivering 5-fluorouracil (5-FU) at increased rates on demand by external microwave irradiation was developed. Sustained-release systems were made by incorporating 5-FU into an ethylene-vinyl alcohol copolymer. When exposed to release medium, the delivery systems released the drug slowly and continuously. Upon exposure to microwave irradiation, the drug was released at a much higher rate. Release rates returned to base line levels when the microwave irradiation was discontinued.This study demonstrated that release rates of 5-FU from a polymer matrix can be increased at desired times by external microwave irradiation.View full abstractDownload PDF (492K) -
Kunio NAKANISHI, Mikio MASADA, Tanekazu NADAI, Kouichiro MIYAJIMA1989 Volume 37 Issue 1 Pages 211-214
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThis investigation was concerned with the change of the bioavailability of a drug owing to the interaction of the drug-β-cyclodextrin complex with bile salts in rat intestinal lumen. The absorption of sulfamethizole (SMZ) from rat intestinal lumen after administration of SMZ-β-cyclodextrin complex was determined by a closed-loop method in the presence of absence of bile. The blood level of SMZ after administration of SMZ-β-cyclodextrin complex was significantly decreased in comparison with that after administration of SMZ alone in bile duct-ligated rats. On the other hand, the blood level of SMZ after SMZ-β-cyclodextrin administration in intact rats (bile duct non-ligated) or on the addition of sodium cholate was similar to the level in the case of SMZ alone. Thus, bile salts were found to act as a competing agent in the gastrointestinal tract.View full abstractDownload PDF (603K) -
Kiyoshi SAKAI, Yohko MIYAZAKI, Toshiko YAMANE, Yukiko SAITOH, Chie IKA ...1989 Volume 37 Issue 1 Pages 215-217
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSome of the Zingiberaceae herbs are known to be useful as stomachics. Water extracts and methanol extracts of eight such herbs were examined in intact unanesthetized rabbits for their effect n gastric secretion. Oral administration of either water extratcs or methanol extracts caused a significant decrease in gastric secretion. A significant effect of these extracts appeared at 3h after administration. The effect of water extracts on gastric secretion was very similar to that of cimetidine, with a significant decrease in acid output. The effect of the methanol extracts was primarily observed as decreased pepsin output.View full abstractDownload PDF (563K) -
Yoshiharu KANEO, Yumie FUJIHARA, Tetsuro TANAKA, Yoko KOZAWA, Hideki M ...1989 Volume 37 Issue 1 Pages 218-220
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSGlutathione was covalently attached to dextra, (T-40) by the CNBr activation method. In mive given a lethal dose of acetaminophen, the 30-d survival rate increased progressicively with coadministration of the conjugate, whereas little improvement was found when free glutathione was given. The dextran conjugate of glutathione maintaied the serum transaminase activities at lower levels after acetaminophen administration, giving effective protection against acetaminophen hepatotoxicity.View full abstractDownload PDF (489K) -
Koichi MORI, Chieko TERASHITA, Yuko FUKUNAGA, Tadashi OKAMOTO, Taeko K ...1989 Volume 37 Issue 1 Pages 221-225
Published: January 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA series of 2, 3-ethylenedioxy-1, 4-benzoquinones having an alkylthio or arylthio side chain at the 5-position or two alkylthio or arylthio side chains at the 5, 6-positions was synthesized. These compounds were tested for inhibition of the succinoxidase and reduced nicotinamide adenine dinucleotide (NADH) oxidase systems in the mitochondrial respiratory chain. 5-Arylthio- and 5, 6-diarylthio-2, 3-ethylenedioxy-1, 4-benzoquinones were found to show potent inhibitory activities toward both enzyme systems. However, 5-alkylthio- and 5, 6-dialkylthio-2, 3-ethylenedioxy-1, 4-benzoquinones showed weak inhibitory activities. The substitution of a 2, 3-ethylenedioxy group in place of the 2, 3-dimethoxy group of coenzyme Q (CoQ) was found to be more favorable than the previously reported 2, 3-dimethyl compound or 1, 4-naphthoquinones for the inhibition of both enzyme systems. The effects of 2, 3-ethylenedioxy-1, 4-benzoquinones on the reduced minus oxidized difference spectra of submitochondrial particles with succinate or NADH as a substrate were investigated to identify their inhibitory sites in the respiratory chain. The spectral changes suggested that 5-arylthio- and 5, 6-diarylthio-2, 3-ethylenedioxy-1, 4-benzoquinones inhibit some sites between succinate and CoQ, as well as after cytochrome a+a3. On the other hand, 5, 6-dialkylthio-2, 3-ethylenedioxy-1, 4-benzoquinones were found to inhibit some sites between NADH and CoQ, as well as after chrochrome a+a3.View full abstractDownload PDF (678K)