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Volume 43, Issue 9
Displaying 1-34 of 34 articles from this issue
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Yoshinori TOMINAGA, Koichiro OGATA, Hiroshi UEDA, Shinya KOHRA, Akira ...1995 Volume 43 Issue 9 Pages 1425-1434
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSN-Cyano- or N-(p-toluenesulfonyl)-N'-(trimethylsilylmethyl)-S-methylisothioureas (3, 4), readily prepared by reactions of S, S'-dimethyl N-cyano- (1a)b and S, S'-dimethyl N-(p-toluenesulfonyl)- (1b) carbonimidodithioates with trimethylsilylmethylamine (2a), followed by N-alkylation, have been found to provide synthetic equivalents of iminoazomethine ylide. Treatment of these compounds with cesium fluoride in the presence of reactive hetero-dipolarophiles such as carbonyl compounds afforded 1, 3-dipolar cycloadducts, 4, 5-dihydro-2-iminooxazoles and 4, 5-dihydro-2-iminothiazoles, via the 1, 3-elimination of (methylthio)trimethylsilane.S-Methyl-S'-trimethylsilylmethyl N-cyano- (5a) and N-(p-toluene-sulfonyl)- (5b) carbonimidodithioates, also readily prepared from the corresponding 1a and 1b with (mercaptomethyl)trimethylsilane (2b), were used as new reagents for introducing a thioformaldehyde unit at a carbonyl carbon. Reactions of these compounds with aldehydes in the presence of cesium fluoride afforded thiiranes via the 1, 3-dipolar cycloaddition of iminothiocarbonyl ylide to the C=O double bond. Reactions of 5 with dimethyl fumarate and maleate in the presence of cesium fluoride in acetonitrile gave 1, 3-dipolar cycloadducts, dimethyl 2-(N-(p-toluenesulfonyl)imino)tetrahydrothiophene-3, 4-dicarboxylates.View full abstractDownload PDF (1665K) -
Shigeko OZAKI, Shizue MITOH, Hidenobu OHMORI1995 Volume 43 Issue 9 Pages 1435-1440
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSubstituted (methylene)cyclopentanes were prepared by one-step reaction at room temperature from butynyl iodides and activated olefins by sequencing of free radical addition and cyclization reactions. The reactions, which were conducted by indirect electroreduction catalyzed by a nickel(II) complex, proceeded with modest selectivity for formation of the Z(methylene)cyclopentanes.View full abstractDownload PDF (1062K) -
Eisuke KAJI, Noriko ANABUKI, Shonosuke ZEN1995 Volume 43 Issue 9 Pages 1441-1447
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWe achieved practical, highly stereoselective syntheses of three interglycosidic isomers of N-acetyl-β-D-mannosaminyl-L-rhamnoses, among which a β(1→4)-isomer corresponds to the repeating unit of the O-antigen of lipopolysaccharide (LPS) from the opportunistic pathogens Pseudomonas cepacia O5 and Pseudomonas aeruginosa X (Meitert). The other isomers are a β(1→2)-disaccharide, a constituent of LPS from Escherichia coli O1A, and an artificial β(1→3)-isomer. The disaccharides were obtained by simple three-step reaction sequences from 2-(benzoyloxyimino)-2-deoxyglycosyl halides (mannosamine progenitor). β-Selective glycosylations of appropriately protected L-rhamnosyl acceptors were performed. Subsequent reduction of the 2-acyloxyimino function to an amino group, N-acetylation, and removal of the protecting groups provided the target disaccharides. 13C-NMR and nuclear Overhauser effect spectra proved to be useful for stractural determination of the positional isomers of the disaccharides.View full abstractDownload PDF (1206K) -
Ji-Zhou WU, Chikako MORIZANE, Akira IIDA, Shin-ichi UEDA, Zuo-Ling ZHO ...1995 Volume 43 Issue 9 Pages 1448-1453
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new diterpenoid, fritillebic acid (1) and four new diterpenoid dimers, fritillebins A (2) and B (3), and fritillebinides A and B, were isolated from a crude drug, bulds of Fritillaria ebeiensis G. D. Yu et G. Q. JI. The structures of compounds 1-3 were determined to be ent-3β-acetoxy-16β-kauran-17-oic acid (1), ent-16β-hydroxykauran-17-yl ent-3β-acetoxy-16β-kauran-17-oate (2), and ent-3β-acetoxy-16β-hydroxykauran-17-yl ent-3β-acetoxy-16β-kauran-17-oate (3), respectively, on the basis of spectroscopic and chemical evidence.View full abstractDownload PDF (795K) -
Akira IIDA, Yoshihito TANAKA, Tomohiro MIHARA, Mamoru TABATA, Gisho HO ...1995 Volume 43 Issue 9 Pages 1454-1457
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo new labdane diterpenoids, marrubinones A (1) and B (2), were isolated from aerial parts of Marrubium astracanicum collected in Turkey. Compounds 1 and 2 were mostly characterized by two-dimensional NMR. For determination of the absolute configuration, the modified Mosher's method was applied to the 12-hydroxy forms of 1 and 2. Compounds 1 and 2 are pentacyclic diterpenoids, which differ from each other only in the stereochemistry at C-13, and they were identified as 9α, 13S : 15, 16-diepoxy-12-oxo-14-labden-19, 6β-olide and 9α, 13R : 15, 16-diepoxy-12-oxo-17-labden-19, 6β-olide, respectively.View full abstractDownload PDF (644K) -
Masumi TAKEMOTO, Yuji MORIYASU, Kazuo ACHIWA1995 Volume 43 Issue 9 Pages 1458-1461
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWe have synthesized optically active α-phenylpyridylmethanols by reduction or hydrolysis with cell cultures of Nicotiana tabacum or immobilized cells of N. tabacum.View full abstractDownload PDF (648K) -
Masayuki YOSHIKAWA, Shoko YAMAGUCHI, Hiroko NISHISAKA, Johji YAMAHARA, ...1995 Volume 43 Issue 9 Pages 1462-1465
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new iridoid lactone, morindolide, and a new iridoid glucoside, morofficinaloside, have been isolated from a Chinese natural medicine, Morindae Radix, the dried root of Morinda officinalis How. Together with a number of known compounds : five antheraquinones, four iridoid glucosides, a monoterpene glycoside, two sterols, an ursane-type triterpene, and a lactone compound. The chemical structures of the new compounds were determined on the basis of chemical and physicochemcial evidence.View full abstractDownload PDF (623K) -
Mayumi KOYAMA, Toshiyuki TAKAGI, Akira ANDO, Itsumaro KUMADAKI1995 Volume 43 Issue 9 Pages 1466-1474
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWe previously synthesized mono(trifluoromethyl)tocopherols, which were used for investigation of the mobility and orientation of tocopherol in Iliposomes by 19F-NMR. For more precise investigation of the behavior of vitamin E in liposomes, tocopherols having two trifluoromethyl groups, one on the prenyl side chain and the other on the chromanol ring, were synthesized. Thusn, dimethylhydroquinones were treated with 6-chloro-3-methyl-2-hexenol in the presence of zinc chloride to give 2-(3-chloropropyl)trimethylchromanol derivatives. These were converted to phosphonium salts, which, upon condensation with trifluoromethylated ketones followed by hydrogenation, gave tocopherols with a trifluoromethyl group on the side chain and a hydrogen on the chromanol part. These were halogenated on the chromanol part and treated with trifluoromethyl iodide and copper powder to give the title compounds.View full abstractDownload PDF (1749K) -
Nobuko SAKURAI, Mamoru KOEDA, Yoshinobu AOKI, Masahiro NAGAI1995 Volume 43 Issue 9 Pages 1475-1482
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThree trinor-triterpenol glycosides were isolated from a batch of commercial Cimicifuga Rhizome : cimicifugoside H-3 (1), C32H48O9, mp 249-251 °C, [α]D -22.3°, cimicifugoside H-4 (2), C32H48O9, mp 265-267 °C, [α]D -75.0°, and cimicifugoside H-6 (3), C32H<48>O10, mp 275-276 °C, [α]D -64.3°, On the basis of chemical and spectral data, the structure of 1 was proposed to be 11β, 24-dihydroxy-3β-(β-D-xylopyranosyloxy)-25, 26, 27-trinor-9, 19-cyclolanost-7-ene-16, 23-dione. Cimicifugoside H-4 (2), 11β, 16α, 24α-trihydroxy-3β-(β-D-xylopyranosyloxy)-25, 26, 27-trinor-9, 19 : 16, 24-dicyclolanost-7-en-23-one, seems to be generated from intramolecular aldol condensation between C-16 and C-24 of 1. Cimicifugoside H-6 (3) is the 15α-hydroxy derivative of 2. Cimicifugoside H-2 (5), which has already been obtained from cimicifugoside H-1 (4) under an acidic condition, was found to give 1, 2 and an α-hydroxy enone (2a) under an alkaline condition.View full abstractDownload PDF (945K) -
Satoshi ONO, Tetsuo YAMAFUJI, Hisaaki CHAKI, Yozo TODO, Mutsuko MAEKAW ...1995 Volume 43 Issue 9 Pages 1483-1487
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSN-(2-Dimethylaminoethyl)carboxamide (1a-d), 2-dimethylaminoethyl alkyl ether (2a, b), and 2-dimethylaminoethyl 2-hydroxy-2-phenethyl ether (3a-c) and its amino and methylene analogues (3d, 4) have been screened for antiamnestic and antihypoxic activitied in mice. A clear reversing effect on electroconvulsive shock-induced amnesia was found with 1a-d, 2a, b, and 2-dimethylaminoethyl 2-hydroxy-2-phenylethyl ether (3a). However, a protective effect against hypoxia was only observed with 3a. Compound 3a, which displayed the dual activity, was further investigated for ameliorating effect on CO2-induced memory impairment, and it was found to be more potent than indeloxazine and bifemelane. In addition, the acute toxicity of 3a in mice was significantly lower than that of tacrine, but its serum-to-brain penetration ability in rats was less than of the reference drugs.View full abstractDownload PDF (794K) -
Satoshi ONO, Tetsuo YAMAFUJI, Hisaaki CHAKI, Hajime MORITA, Yozo TODO, ...1995 Volume 43 Issue 9 Pages 1488-1491
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA series of 2-(2-aminoethoxy)-1-phenylethanols having a variety of N- and phenyl-substitution patterns as well as 5- and 6-membered heteroaryl counterparts of our prototype compound 1 (2-(2-dimethylaminoethoxy)-1-phenylethanol) have been prepared and evaluated for antiamnestic and antihypoxic activities. Compound 3b, the 3-methylphenyl analogue of 1, proved to be significantly more potent than 1 in reversing eelctroconvulsive shock-induced amnesia as well as CO2-induced learning-impairment in mice. It exhibited low acute toxicity in mice and afforded a greater brain/serum concentration ratio than 1 after oral administration to rats.View full abstractDownload PDF (694K) -
Satoshi ONO, Tetsuo YAMAFUJI, Hisaaki CHAKI, Hajime MORITA, Yozo TODO, ...1995 Volume 43 Issue 9 Pages 1492-1496
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS2-(2-Aminoethoxy)-1-hydroxyethyl derivatives of bicyclic arenes) naphthalene, thianaphthene, benzofuran, and indole) were prepared and screened for antiamnestic (AA) and antihypoxic (AH) activities which were evaluated by measuring the reversing potency in electroconvulsion-induced amnesia and the protective effect against hypoxia, respectively, in mice. Compound 3o, 1-(benzo[b]thiophen-5-yl)-2-(2-diethylaminoethoxy)ethanol, showed the best AA and AH activity profile, being superior to our prototype compound, 2-(2-dimethylaminoethoxy)-1-phenylethanol (1). Elongation of the ethylene linkage in the side chain of 3o to 3- and 4-carbon moiethies brought about a significant decrease in AH activity. Compound 3o was further investigated for its protective effect against Co2-induced memory impairment and for acute toxicity in mice. It is ten-fold more potent than tacrine in the amnesia-reversal assay and is considerably less toxic than tacrine.View full abstractDownload PDF (788K) -
Mitsuru OHKUBO, Atsushi KUNO, Isao NAKANISHI, Hisashi TAKASUCI1995 Volume 43 Issue 9 Pages 1497-1504
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSVarious 2-aminothiazoles (2a-s and 3a-g) and 2-thiazolecarboxamides (4a-h), possessing a nitrogenous basic moiety at the C-2 position of the thiazole ring, were prepared and tested for anti-anoxic (AA) activity in mice. Among them, N-[2-(4-morpholinyl)ethyl]-4-(3-trifluoromethylphenyl)-2-thiazolecarboxamide hydrochloride (4e, FR108143) (minimum effectvie doses of 3.2 mg/kg i.p. and 10 mg/kg p.o., respectively) exhibited more potent AA activity than either FK360 or compound 1, each of which has a nitrogenous basic moiety at the C-5 position. The structure-activity relationships with regard to AA activity of this series of compounds are discussed, and the three-dimensional electrostatic potentials (3D-MEP) around the basic nitrogen atom of FK360 and the thiazole derivative (4e) are compared.View full abstractDownload PDF (1436K) -
Masaaki KUWAHARA, Yasuhiko KAWANO, Tatsuhiko KAWAI, Yasuko ASHIDA, Aki ...1995 Volume 43 Issue 9 Pages 1505-1510
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA series of novel ω-substituted alkylthioimidazo[1, 2-b]pyridazines was designed and synthesized in an effort to find a novel anti-asthmatic agent. The anti-asthmatic activity of these compounds was evaluated ont he basis of their ability to inhibit thromboxane A2 synthetase and platelet activating factor (PAF)-induced bronchoconstriction in guinea pigs. None of these compounds significantly inhibited thromboxane A2 synthetase, though, sulfonamide derivatives potently inhibited PAF-induced bronchoconstriction. Among them, 3-(imidazo[1, 2-b]pyridazin-6-yl)thiopropanesulfonamide (5) showed the most potent inhibitory effect. The anti-asthmatic effects of compound 5 in experimental models were superior to those of theophylline.View full abstractDownload PDF (1030K) -
Masaaki KUWAHARA, Shinji KATO, Tohru SUGAWARA, Akio MIYAKE1995 Volume 43 Issue 9 Pages 1511-1515
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFor the purpose of improving the anti-asthmatic activity of 3-(imidazo[1, 2-b]pyridazin-6-yl)thiopropanesulfon-amide (I), the computer-assisted automated synthesis apparatus developed at Takeda was used to modify the sulfon-amide moiety of I. Several kinds of sulfonamide derivatives (1-24) were easily obtained, confirming the usefulness of the automated synthesis apparatus in the laboratory. Anti-asthmatic activity of these derivatives was examined in a platelet activating factor (PAF)-induced bronchoconstriction. Among them, the piperidino-piperidine derivative (13) was found to possess comparable activity to that of I.View full abstractDownload PDF (782K) -
Masaaki KUWAHARA, Yasuhiko KAWANO, Hiroshi SHIMAZU, Hiroaki YAMAMOTO, ...1995 Volume 43 Issue 9 Pages 1516-1522
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA series of novel alkylthioimidazo[1, 2-b]pyridazines was synthesized and evaluated for ability to inhibit platelet activating factor (PAF)-induced bronchoconstriction in guinea pigs. Among them, 3-(imidazo[1, 2-b]pyridazin-6-yl)thio-2, 2-dimethylpropanesulfonamide (15) showed the most potent inhibitory effect. The structure-activity relationships in this series of compounds, in particular, the effects of conversiton of the imidazopyridazine ring into other heterocyclic rings, introduction of a substituent group at the 2 or 3 position of the imidazopyridazine ring and introduction of a substituent group into the alkyl side chain, are also discussed.View full abstractDownload PDF (988K) -
Shin-ichi TSUKAMOTO, Hitoshi NAGAOKA, Susumu IGARASHI, Fumikazu WANIBU ...1995 Volume 43 Issue 9 Pages 1523-1529
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA series of novel 2, 8-dialykl-1-oxa-2, 8-diazaspiro[4.5]decan-3-ones and 2, 8-dimethyl-1, 2, 8-triazaspiro[4.5]-decan-3-one (13), related to M1 muscarinic agonists YM796 and RS86, were synthesized by using Michael addition reaction of hydroxyurea or methylhydrazine to α, β-unsaturated esters followed by cyclization reaction. These compounds were assessed for binding affinities for M1 and M2 receptors and in vivo muscarinic activity : namely, amelioration of scopolamine-induced impairment in rat passive avoidance tasks and induction of hypothermia, tremor, and salivation. 2, 8-Dimethyl-1-oxa-2, 8-diazaspiro[4.5]decan-3-one (6a) exhibited high affinities for both M1 and M2 receptors, showed antiamnesic activity (0.1 mg/kg, s.c.) and induced hypothermia (3 mg/kg, s.c.). In addition, 6a stimulated phosphoinositide hydrolysis in rat hippocampal slices, indicating partial agonistic activity for M1 muscarinic receptors. The alteration of the methyl group at N2 of 6a increased the selectivity in binding affinities for M1 over M2 receptors, but resulted in loss of M1 agonistic activity or antiamnesic activity. Compound 13 exhibited only low affinity for M1 receptors, suggesting that a basic nitrogen atom is not tolerated in M1 receptor binding as a substitute for an oxygen atom or a carbonyl group at the 1-position of 6a or RS86. None of these derivatives exhibited high selectivity for antiamnesic effect over induction of hypothermia compared to YM796.View full abstractDownload PDF (1345K) -
Satoru NAGAMURA, Yutaka KANDA, Eiji KOBAYASHI, Katsushige GOMI, Hiromi ...1995 Volume 43 Issue 9 Pages 1530-1535
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA series of duocarmycin B2 dirivatives, modified at the phenolic hydroxyl group to ester, carbonate and carbamate, was synthesized. Antitumor activity of these analogs was preliminarily evaluated by assays of growth inhibition of HeLa S3 cells (in vitro) and antitumor activity against murine sarcoma 180 (in vivo). The stability of the compounds under aqueous conditions was examined, and we found a correlation between antitumor activity in vivo and stability in aqueous solution, that is, the more stable derivatives exhibited higher antitumor activity. Among these derivatives, the N, N-dialkylcarbamoyl analogs exhibited both improved antitumor activity and higher stability compared with duocarmycin B2. These analogs were subjected to further biological evaluation and they expressed broad-spectrum activity toward murine solid tumors M5076, Colon 26 and Colon 38, and human xenografted carcinoma MX-1.View full abstractDownload PDF (1136K) -
Yoshihiro NAGAO, Takahiro NEKADO, Kiyoshi IKEDA, Kazuo ACHIWA1995 Volume 43 Issue 9 Pages 1536-1542
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSGanglioside GM4 (1) and GM3 (2) analogs, which contain mimics of the ceramide moieties of gangliosides, were synthesized. The syntheses of 1 and 2 feature stereoselective glycosylation of methyl (phenyl 5-acetamido-4, 7, 8, 9-tetra-O-acetyl-3, 5-dideoxy-2-thio-β-D-galacto-2-nonulopyranosid)onate (10) as the sialosyl donor with suitably protected galactose and lactose acceptors catalyzed by N-bromosuccinimide (NBS), iodine, and tetrabutylammonium trifluotomethanesulfonate (TBAOTf) as the glycosyl promoter in acetonitrile under kineticaly controlled conditions. Compound 2 exhibited binding activity towards influenza virus A.View full abstractDownload PDF (978K) -
Masaru KIHARA, Motoki IKEUCHI, Satoko ADACHI, Yoshimitsu NAGAO, Hideki ...1995 Volume 43 Issue 9 Pages 1543-1546
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSOptically active 1, 2-dimethyl-4-phenyl-1, 2, 3, 4-tetrahydroisoquinolin-4-ols (1R, 4R-3a and 1S, 4S-3b, 1S, 4R-4a, and 1R, 4S-4b) and 2-methyl-4-phenyl-1, 2, 3, 4-tetrahydroisoquinolines (4S-5a and 4R-5b) were prepared in order to examine the effects of the 1-, 3-, and 4-substituents of 2-methyl-4-phenyl-1, 2, 3, 4-tetrahydroisoquinolin-4-ol (PI-OH) (1) on the enantioselectivity for norepinephrine (NE) potentiating activity. The conformations and absolute configurations of 3-5 were determined from their 1H-NMR and circular dichroism (CD) spectra and by single-crystal X-ray diffractometric analysis. The NE potentiating activity of the optically active 3-5 and previously prepared 3-methyl derivatives (3R, 4R-6a and 3S, 4S-6b) of PI-OH were tested. The results show that compounds 3, 4, and 6 had high enantioselectivity for NE potentiation : the 4R series of the enantiomers exhibited activity but not the 4S-enantiomers. The activity of the 4-desoxy compound 5 also resided exclusively in the 4S-enantiomer. These findings suggest the presence of a specific receptor for NE uptake, and the enantiomers 3a, 4a, 5a, and 6a may be antagonistic at this NE uptake receptor.View full abstractDownload PDF (765K) -
Akihiro AMBO, Takayuki ADACHI, Yusuke SASAKI1995 Volume 43 Issue 9 Pages 1547-1550
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS[D-Leu8]Dynorphin(1-8)-NH2 analogs, in which each peptide bond was systematically replaced with a ψ(CH2NH) peptide bond, were synthesized by the solid-phase method. The ψ(CH2NH) bond was introduced by the Boc-amino acid aldehyde/NaCNBH3 method on a solid support. In the syntheses of the analogs, undesirable double alkylation took place at the sequences of Tyr1ψ(CH2NH)Gly2 and Gly2ψ(CH2NH)Gly3, possible due to the low steric hindrance of the glycine residue. To suppress the double alkylaiton, a minimum amount of aldehydes was employed. In the receptor binding assay, the ψ(CH2NH) replacement of N-terminal peptide bonds which led to 1ψ2- (2) and 2ψ3-analogs (3) resulted in a marked reduction in binding affinities for μ-, δ-, and κ-opioid receptors, while that of the other peptide bonds afforded analogs with a high κ-receptor affinity. A 3ψ4-analog (4) showed extremely high κ-receptor selectivity (μ/κ Ki ratio=339, δ/κ Ki ratio=24104). In the in vitro bioactivity assay (guinea pig ileum assay), 2 showed a very low IC50 ratio (2.0) in the presence and absence of peptidase inhibitors whereas those of other analogs were >27, suggesting that the introduction of the CH2NH isostere at Tyr1-Gly2 greatly enhanced the enzymatic stability of the parent peptide. Furthermore, analogs 2 and 3 showed a very low sensitivity to the inhibitory effect of NaCl plus 5'-guanylylimidodiphosphate of their binding at a κ-receptor site as compared with the other analogs and the parent peptide. These results suggest that the two analogs (2 and 3) have partial κ-antagonist properties.View full abstractDownload PDF (746K) -
Takao KUROSAWA, Yukihiro NOMURA, Reijiro MAHARA, Teruki YOSHIMURA, Aki ...1995 Volume 43 Issue 9 Pages 1551-1557
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe synthesis of 19-hydroxylated bile acids (3α, 19-dihydroxy-, 3α, 7α, 19-trihydroxy-, 3α, 12α, 19-trihydroxy-and 3α, 7α, 12α, 19-tetrahydroxy-5β-cholan-24-oic acids) was described. These synthesized 19-hydroxylated bile acids were used as standard samples for the analysis of bile acids in human urine by gas chromatography-mass spectrometry. 3α, 7α, 12α, 19-Tetrahydroxy-5β-cholan-24-oic acid was identified in neonatal urines (0.1-1.5 μg/ml and 1.5-7% of total bile acids).View full abstractDownload PDF (902K) -
Purusotam BASNET, Shigetoshi KADOTA, Koji HASE, Tsuneo NAMBA1995 Volume 43 Issue 9 Pages 1558-1564
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFive new compounds, matteuorien, matteuorienin, and matteuorienate A (7), B (8), and C (9) were isolated together with five known compounds from the MeOH extract of the rhizome of Matteuccia orientalis TREV. The structures of these compounds were determined by the use of spectroscopic methods including two dimensional (2D)-NMR experiments and chemical methods, except for the configuration at the C-3‴ of matteuorienate A (7), B (8), and C (9). Among them, matteuorienate A, B, and C showed very strong aldose reductase inhibitory activity. A structure-activity relationship study showed that a carboxyl group played an important part in aldose reductase inhibitory activity in these three compounds.View full abstractDownload PDF (1076K) -
Kaoru UMEHARA, Naomi SUMII, Hiroko SATOH, Toshio MIYASE, Masanori KURO ...1995 Volume 43 Issue 9 Pages 1565-1568
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSix pregnane glycosides and three cardenolides were isolated as differentiation inducers using mouse myeloid leukemia (MI) cells from Periplocae Radicis Cortex (bark of Periploca sepium BGE., Asclepiadaceae). The cardenolides showed much higher activities than the pregnane glycosides. Besides these nine compounds, commercially available cardenolides were tested for their differentiation inducing activities using MI cells. Digitoxin and digoxin induced MI cells into phagocytic cells, but others did not. In the presence of 1 nM of actinomycin-D, the activity of steroid glycosides was enhanced against MI cells.View full abstractDownload PDF (551K) -
Takahiro UCHIDA, Kazushi YOSHIDA, Akiko NINOMIYA, Shigeru GOTO1995 Volume 43 Issue 9 Pages 1569-1573
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSPolylactide (PLA) microspheres containing ovalbumin (OVA) as a model protein were prepared by a water-in-oil -in -water (w/o/w) emulsion solvent evaporation method. The optimization of preprative parameters for the PLA microspheres containing OVA were performed, and the in vitro characteristics of the obtained microspheres were examined. Firstly, a smaller internal aqueous phase volume was found to be advantageous in obtaining high loading efficiency. Secondly, the addition of 2-10% (w/v) NaCl into the external aqueous phase (0.5% (w/v) polyvinyl alcohol solution) also impreved OVA loading efficiency. Prepared products showed a sharp release of OVA at the initial phase, but the following phase was characterized by a slow release rate of OVA that continued at least 28 d. The release rate of OVA from microspheres made of PLA with a molecular weight of 15400 was faster than that from microspheres made of PLA with a molecular weigh of 58300. However, the LA/GA (lactide/glycolide) ratio was not likely to have much effect on the release profile of OVA. Finally, the effect of PLA microsphere particle size on the release profiles of OVA was examined. The extent of burst release at the initial plase increased as the mean diameter of prepared PLA microspheres decreased. For example, the PLA microspheres with a small mean diameter (5.0 μm) showed a 40% burst release, but almost 30% of OVA remained in the PLA microspheres (confirmed by HPLC method) after the 28 d release test, suggesting the possibility of using this carrier as a long-acting protein delivery system.View full abstractDownload PDF (1101K) -
Tetsuya OZEKI, Hiroshi YUASA, Yoshio KANAYA, Katsutoshi OISHI1995 Volume 43 Issue 9 Pages 1574-1579
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSolid dispersions were prepared with a highly water-soluble medicine (oxprenolol hydrochloride (OXP)), water-insoluble ethylcellulose (EC) and four grades of water-soluble hydroxypropylcellulose (HPC) having different molecular weights. The effects of the composition ratio within the range of 5% of HPC and of the viscosity of HPC hydrogels on the release of OXP were studied. The bulk viscosity of HPC hydrogels was evaluated from the relationship between shear rate and shear stress. The microscopic viscosity was evaluated by the spin probe method of the electron spin resonance (ESR) technique.The release rate of OXP decreased with increasing HPC composition ratio and became almost constant at the HPC composition ratio of 3% and more. This result suggests that the release of OXP will occur through its diffusion into the swollen HPC gel phase formed in a solid dispersion at the HPC composition ratio of 3% and more. The bulk viscosity of HPC hydrogels markedly increased with increasing molecular weight of HPC, but there was little noticeable change in release rate and activation energy for the diffusion of OXP. This result can be explained by the fact that the microscopic viscosity was hardly affected by the molecular weight of HPC, suggesting that the resistance to diffusion of OXP into the swollen HPC gel phase in the solid dispersion was almost the same regardless of the moleclar weight of HPC.View full abstractDownload PDF (822K) -
Hiromasa SEKINE, Nahomi OHONUKI, Kenji SADAMASU, Kimio MONMA, Yasuo KU ...1995 Volume 43 Issue 9 Pages 1580-1584
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe crude water extract (NS-1) from a seaweed (Digenea simplex C. AGARDH Rhodomelaceae) exhibited anti-human immunodeficiency virus (HIV)-1 activity in vitro. The inhibitory effect of the extract on the cytopathic activity of HIV-1 and it's antigen production was examined using a microplate method, immunofluorescent assay, and an HIV antigen detection kit (Abbott). NS-1 inhibited both the cytopathic effect of HIV-1 to MT-4 cells and the giant cell formation of Molt-4 cells infected with HIV-1.View full abstractDownload PDF (629K) -
Michiyasu TAKAHASHI, Rie KOIKE, Kunio OGASAWARA1995 Volume 43 Issue 9 Pages 1585-1587
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSOptically pure inden-1-ol has been obtained efficiently in both enantiomeric forms via kinetic deacylation of racemic 1-acetoxyindene using lipase PS.View full abstractDownload PDF (600K) -
Shirou MAEDA, Hiroshi MASUDA, Takashi TOKOROYAMA1995 Volume 43 Issue 9 Pages 1588-1591
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSOxidation of hydrody-α-methylcinnamate 5 derived from 4-methylesculetin afforded the α-methylcaffeoquinone derivative 7 without formation of the oxidative coupling product. The reaction of the α-methylferulate derivative 13 afforded a complex mixture of products. Thus, the hydroxy-α-methylcinnamates seem not to be suitable substrates for oxidative coupling.Compound 7 was tested for inhibitory effect on lipid peroxidation. It showed more potent activity than idebenone in rat brain homogenate, and was much more potent than (±)-α-tocopherol in rat liver microsomes.View full abstractDownload PDF (594K) -
Kotaro IIDA, Kazumi DANJO, Akinobu OTSUKA, Hisakazu SUNADA1995 Volume 43 Issue 9 Pages 1592-1594
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSEffects of electrostatic force on adhesion between pharmaceutical powder particles (phenacetin and sulfadimethoxine) and various polymer substrates (polyethylene (PE), polyvinylchloride (PVC), Eudragit E100, polyvinylacetal diethylamino acetate (AEA), Eudragit L30D-55) were investigated using the centrifugal separation technique. Two methods were used to attach powder particles to a substrate, the free falling method and the fluidization method. Average adhesive force, f50, and electric potential, V, in the fluidized method were found to be greater than those in the free falling method for all lthe pharmaceutical powder/polymer substrate systems examined. Average adhesive force, f50, increased with a decrease in surface polarity, P0, of polymer substrate for each powder.View full abstractDownload PDF (491K) -
Motomasa KOBAYASHI, Taifo MAHMUD, Takashi UMEZOME, Isao KITAGAWA1995 Volume 43 Issue 9 Pages 1595-1597
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe absolute stereostructure of panaxytriol (1), a diacetylenic constituent of Ginseng Radix Rubra, was determined by applying the modified Mosher method and the CD exciton chirality method to be expressed as (3R, 9R, 10R)-heptadec-1-ene-4, 6-diyne-3, 9, 10-triol.View full abstractDownload PDF (442K) -
Motomasa KOBAYASHI, Weiqi WANG, Naoki OHYABU, Michio KUROSU, Isao KITA ...1995 Volume 43 Issue 9 Pages 1598-1600
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAn efficient asymmetric synthesis of a cyclic depsipeptide arenastatin A (1) is described. 1, isolated from the marine sponge Dysidea arenaria, exhibited extremely potent cytotoxicity with IC50 of 5 pg/ml for KB cells, and in this context the structure-activity relationship among several stereoisomers of 1 and allied compounds has also been examined.View full abstractDownload PDF (449K) -
Atsuhiro INABA, Kousuke INAMI, Yuichi KIMOTO, Reiko YANADA, Yoshihisa ...1995 Volume 43 Issue 9 Pages 1601-1603
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe stereospecific synthesis is described of the first member of a new class of C-nucleoside analogues in which the sugar ring is replaced with a 1, 3-thiazolidine ring. The 1, 3-thiazolidin-2-yl analogues (1) and (2) of pseudouridine were prepared stereospecifically via condensation of L or D-cysteine with a formylated nucleobase.View full abstractDownload PDF (458K) -
Yuji KOSEKI, Tatsuo NAGASAKA1995 Volume 43 Issue 9 Pages 1604-1606
Published: September 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThis paper presents the formal synthesis of lennoxamine (1), the key step [4 into 10 via 9] of which is a novel palladium-catalyzed coupling reaction followed by intramolecular cyclization of alkynylamide.View full abstractDownload PDF (427K)
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