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Takefumi MOMOSE, Kikuo MASUDA, Sachiko FURUSAWA, Osamu MURAOKA, Toshiy ...
1990 Volume 38 Issue 6 Pages
1707-1711
Published: June 25, 1990
Released on J-STAGE: March 31, 2008
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The characteristics intramolecular aldol cyclization of bicyclo[4.3.1]decanedione to two novel tricyclic systems, protoadamantanone and isotwistanone, is described. Both systems were reconverted to bicyclo[4.3.1]decanones by the Grob fragmentation.
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Yoshiaki SHIRATAKI, Tomohide TSUZUKU, Ichiro YOKOE, Robert T. HIRANO, ...
1990 Volume 38 Issue 6 Pages
1712-1716
Published: June 25, 1990
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Two new isoflavanone, named sophoraisoflavanone C (), mp 107-109°C, C
30H
36O
5 and sophoraisoflavanone D (2), mp 118-120°C, C
30H
36O
6, and a new 6a-hydroxypterocarpan, named (-)-tuberosin (3), mp 203-205°C, C
20H
18O
5, were isolated from the roots of Sophora chrysophylla SEEM. (Leguminosae), together with isoliquiritigenin, 7, 4'-dihydroxyflavone, isosophoranone, l-maackiain, medicagol and sophoracoumestan A. The structures of 1, 2 and 3 were established to be 5, 7, 4'-trihydroxy-6-(3, 3-dimethylallyl)-3'-geranylisoflavanone, 5, 7, 2', 4'-tetrahydroxy-6-(3, 3-dimethylallyl)-5'-geranylisoflavanone and 6aS, 11aS-3, 6a-dihydroxy[2', 2'-dimethylpyrano(5', 6' : 8, 9)]pterocarpan by means of spectral analysis, respectively.
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Tadao ISHIZUKA, Koreichi KIMURA, Seigo ISHIBUCHI, Takehisa KUNIEDA
1990 Volume 38 Issue 6 Pages
1717-1719
Published: June 25, 1990
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Starting with (1S)-ketopinic acid (7, 7-dimethyl-2-oxo-bicyclo[2.2.1]heptane-1-carboxylic acid), a facile high-yield synthesis of diastereomerically pure (1S, 2R)- and (1S, 2S)-2-hydroxy-7, 7-dimethylbicyclo[2.2.1]heptane-1-carboxylic acids, potentially useful as chiral auxiliaries, has been achieved : the key step for the latter (2-endo isomer) involves the base-catalyzed epimerization of the (1S, 2R)-2-hydoxy isomer (2-exo-isomer), exclusively formed by the L-Selectride
[○!R] reduction of alkyl ketopinate, via the retro-aldol reaction.
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Atsuko NOSE, Tadahiro KUDO
1990 Volume 38 Issue 6 Pages
1720-1723
Published: June 25, 1990
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The reductino of a variety of functional groups with new dimethoxyborane-transition metal boride systems was investigated. These systems reduced olefin, aldehyde, ketone and nitrile functionalities to afford the corresponding reduction products under mild conditions. In particular, olefins bearing ketone, carboxylic acid and nitrile functionalities were selectively reduced with the dimethoxyborane-nickel boride system using 1/5mol eq of nickel boride.
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Masaru KOBAYASHI, Fuyuko KANDA, Chunduri Venkata Lakshmana RAO, Saridi ...
1990 Volume 38 Issue 6 Pages
1724-1726
Published: June 25, 1990
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Nine polyhydroxysterols were isolated from the lipid extract of two Sclerophytum sp. soft corals collected in the Andaman and Nicobar islands. Of these, seven compounds (1, 4a-6c) had previously been isolated from southern Japan soft coral Sarcophyton glaucum. The structures of the two new steroids 2 and 3 were determined as (24S)-24-methylcholest-5-ene-3β, 25ζ, 26-triol and (24S)-24-methylcholestane-3β, 5β, 6α, 25-tetrol, respectively, by means of spectroscopic analyses, and by correlation with the known compounds.
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Takeo OKAZAKI, Katsuyuki KURUMAYA, Masahiro KAJIWARA
1990 Volume 38 Issue 6 Pages
1727-1730
Published: June 25, 1990
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The enzymes which transform δ-aminolevulinic acid into porphobilinogen and uroporphyrinogen were isolated and partially purified for use in a cell-free system. A technique was developed for direct observation of the time course of the reactinos in this system by carbon-13 nuclear magnetic resonance (
13C-NMR) spectroscopy, using
13C-labeled aminolevulinic acid as the substrate.
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Kouki KITAGAWA, Takahiro TOMOYASU, Shiroh FUTAKI, Tadashi AKITA, Shuni ...
1990 Volume 38 Issue 6 Pages
1731-1734
Published: June 25, 1990
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Human peptide YY (hPYY) was synthesized in a conventional manner by assembling six peptide fragments followed by deprotectio with 1 M trimethylsilyl trifluoromethanesulfonate (TMSOTf)-thioanisole in trifluoroacetic acid (TFA). After purification by gel-filtration on Sephade G-25, followed by reversed-phase high-performance liquid chromatography, a highly purified sample of synthetic hPYY was obtained. When administered in dogs, synthetic hPYY was as active as synthetic porcine PYY in terms of the effects on systemic arterial blood pressure, and splanchnic blood flow.
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Hiroshi YOSHINO, Masahiko TSUJII, Masato KODAMA, Keisuke KOMEDA, Nobuo ...
1990 Volume 38 Issue 6 Pages
1735-1737
Published: June 25, 1990
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A large-scale synthesis of [MeTyr
1, MeArg
7, D-Leu
8]dynorphin A-(1-8)-NHEt (E-2078), which is a systemically active dynorphin A-(1-8) analogue, was accomplished by the classical solution method applying the trifluoroacetic acid-pentamethylbenzene deprotecting procedure in the final stage.
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Hiroyuki ISHIBASHI, Hiroshi NAKATANI, Duk Jae CHOI, Maromi TAGUCHI, Ma ...
1990 Volume 38 Issue 6 Pages
1738-1739
Published: June 25, 1990
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In the presence of AlCl
3, m-tolylthiomethyl chloride (1) reaceted with methyl 3, 4-dimetylcyclopent-3-ene-1-carboxylate (4) to give the [4
++2] polar cycloadditino product 6, which was transformed into (±)-β-cuparenone (11) in 4 steps.
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Toshimitsu FUKUMURA, Hideki DOHMOTO, Minoru MAEDA, Etsuko FUKUZAWA, Ma ...
1990 Volume 38 Issue 6 Pages
1740-1742
Published: June 25, 1990
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With the aim of developing fluorinated benzamides that may be useful as radioligands for positron emission tomography, fluorine analogs of eticlopride, in which the N-ethyl group was replaced by 2-fluoroethyl, 3-fluoropropyl and p-fluorobenzyl groups, were synthesized. These derivatives were tested for their ability to displace [
3H]spiperone from its specific dopamine D-2 receptor. Their potencies were decreased when compared with eticlopride, but the two fluoroalkylated analogs were in the same order of magnitude as that of haloperidol.
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Satomi HIRONO, Wen-Hua CHOU, Ryoji KASAI, Osamu TANAKA, Toshiharu TADA
1990 Volume 38 Issue 6 Pages
1743-1744
Published: June 25, 1990
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From leaves of Rubus suavissimus, two minor ent-kaurane type diterpene glucosides were isolated in addition to the major sweet principle, rubusoside (1). Of these glucosides, the bitter glycoside (2) was identified as sugeroside which has been isolated from leaes of Ilex sugerokii var. Brevipedunculata etc. The new glucoside (3) named suavioside-A tastes sweet and the structure was elucidated as 17-O-β-D-glucoside of ent-kaurane-3α, 16β, 17-triol.
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Kazuo SAITO, Motohiro NISHIJIMA, Toshio MIYAZAKI
1990 Volume 38 Issue 6 Pages
1745-1747
Published: June 25, 1990
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Analytical data of Smith-type degradation products and carbon-13 nuclear magnetic resonance spectroscopy of an alkali-soluble glucan, OL-2, which was isolated from a crude fungal drug "Leiwan" (Omphalia lapidescens), suggested that OL-2 was a β-1, 3-D-glucan possessing approximately two branches at every three main chain glucosyl unit at each C-6 position. Antitumor activities of OL-2 and the degradation product, OR-OL-2c, against the solid form of sarcoma 180 in ICR mice were negative.
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Takaaki AOYAGI, Takao WADA, Machiko NAGAI, Fukiko KOJIMA, Shigeko HARA ...
1990 Volume 38 Issue 6 Pages
1748-1749
Published: June 25, 1990
Released on J-STAGE: March 31, 2008
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In order to search for more proximal factors in the pathogenesis of Alzheimer's disease, we studied the activities of various enzyme in the brains of patients, as well as control cases, by postmortem autopsy. In addition to the findings already known, such as the increase in prolyl endopeptidase (post-proline cleaving enzyme, PPCE) activity and the decrease in kallikrein activity, we found, anew, an increase in aminobutyrate aminotransferase (GABA-T) activity in the Alzheimer brain. This may be an important impetus for the reduction of γ-aminobutyric acid (GABA) in the brain, one of the neurotransmitters. It has to be determined whether the former two abnormalities offer a background for such an abnormality of the neurotransmitter.
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Takaaki AOYAGI, Takao WADA, Fukiko KOJIMA, Machiko NAGAI, Shigeko HARA ...
1990 Volume 38 Issue 6 Pages
1750-1752
Published: June 25, 1990
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We previously reported an increase in aminobutyrate aminotransferase (GABA-T) activity in the cerebrum of Alzheimer patients. In the present study, we investigated whether such findings are common in the usual aging process as well. We examined the activity of various enzymes, which were examined in the previous study, in the cerebrum of Wistar-Kyoto rats and spontaneously hypertensive rats. In the two strains, we compared the enzyme activities between the two groups of animals, 5 weeks and 13 weeks of age. In both strains, the older animals had significantly higher activities of GABA-T and choline acetyltransferase (ChAc-T). In spite of other enzymatic changes coexisting, the above two enzymes were suggested by discriminant function analysis to be playing a major role in the multiple enzymatic changes in the cerebrum of the animals.
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Toshio NANBO, Noboru FUKASAKU, Michio YAMAGUCHI, Hideyuki TAKAGI, Taka ...
1990 Volume 38 Issue 6 Pages
1753-1754
Published: June 25, 1990
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The relationship between the glycine conjugation of 4-substituted derivatives of benzoic acid and physico-chemical property was studied using rats. A linear relationship was found between the lipophilicity and the glycine conjugation after the intravenous injection of the derivative into rats. But there was no relationship between the lipophilicity and permeability into the liver. The formation of the glycine conjugate using mitochondria fraction of the liver was responsible for the superdelocalizability indicating the electrophilicity of carboxyl carbon.
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Ichimaro YAMADA, Keiichiro HAGA
1990 Volume 38 Issue 6 Pages
1755-1756
Published: June 25, 1990
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The behavior of gastric pH during digestion of a solid meal in beagle dogs was determined by use of an ion-selective field effect transistor pH sensor. The pH in the stomach was 3.9±0.4 (mean±S.D., n=6) at 0.5h after meals. It was maintained at a mildly acidic (about pH 3) level for long periods.
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Sumie YOSHIOKA, Yukio ASO, Yasushi TAKEDA
1990 Volume 38 Issue 6 Pages
1757-1759
Published: June 25, 1990
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Accelerated stability data obtained at a single temperature is statistically evaluated, and the utility of such data for assessment of stability is discussed focussing on the chemical stability of solution-state dosage forms. The probability that the drug dontent of a product is observed to be within the lower specification limit in the accelerated test is interpreted graphically. This probability depends on experimental errors in the assay and temperature control, as well as the true degradation rate and activation energy. Therefore, the observation that the drug content meets the specification in the accelerated testing can provide only limited information on the shelf-life of the drug, without the knowledge of the activation energy and the accuracy and precision of the assay and temperature control.
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Sumie YOSHIOKA, Yukio ASO, Yasushi TAKEDA
1990 Volume 38 Issue 6 Pages
1760-1762
Published: June 25, 1990
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Accelerated stability data obtained at a single temperature (40°C) is statistically evaluated and the utility of the actual value of remaining drug content observed in the test for estimation of shelf-life is discussed. The distribution of the time required for 10% degradation at 25°C, t
90(25), is calculated from the observed drug content, taking the experimental errors into consideration. The probability that the t
90(25) is longer than a specified shelf-life, which is calculated from the distribution, is represented as a function of the observed drug content. The probability was found to depend on the experimental errors in the assay and temperature control as well as in the activation energy of degradation (E
a). The relationship between the observed drug content and the shelf-life assured with a certain probability is shown graphically, so that one can reasonably predict the expected shelf-life as a function of E
a if the accuracy and precision of the assay and temperature control are known.
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Sansei NISIBE, Hidehiro KINOSHITA, Hidekatsu TAKEDA, Goroh OKANO
1990 Volume 38 Issue 6 Pages
1763-1765
Published: June 25, 1990
Released on J-STAGE: March 31, 2008
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Ten phenolic compounds, isofraxidin (1), (+)-syringaresinol-di-O-β-D-glucoside (2), syringin (3), chlorogenic acid (4), isofraxidin-7-O-β-D-glucoside (5), 2, 6-dimethoxy-p-benzoquinone (6), (+)-pinoresinol-O-β-D-glucoside (7), (+)-syringaresinol-O-β-D-glucoside (8), (+)-pinoresinol-di-O-β-D-glucoside (9), and (+)-medioresinol-di-O-β-D-glucoside (10), were isolated from the stem bark of Acanthopanax senticosus HARMS and identified, respectively.The aquenous extract of the stem bark exhibited a prolonging effect on the exercise time to exhaustion in chronic swimming stressed rats. The effect on the exercise time in the chronic swimming stressed rats was respectively tested for compounds 2 and 4, which are major constituents of the stem bark. As a result, it was indicated that compound 2 is the compound responsible for part of the pharmacological effect which the aqueous extract of the stem bark showed.
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Keisuke IDEGAMI, Kiyoshi IKEDA, Kazuo ACHIWA
1990 Volume 38 Issue 6 Pages
1766-1768
Published: June 25, 1990
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New 1-thyminyl-D-glucosamine-4-phosphate and 1-thyminyl-D-glucosamine-4, 6-disulfate derivatives were synthesized. The 1-thyminyl-D-glucosamine-4, 6-disulfate derivative showed antiviral activity against HIV.
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Katsuhiko ISEKI, Toshiji KANAYAMA, Yosio HAYASI, Masakatsu SHIBASAKI
1990 Volume 38 Issue 6 Pages
1769-1771
Published: June 25, 1990
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The chemically stable prostacyclin analogue (Z)-4, 5-didehydroisocarbacyclin analogue (6) has been synthesized. Compound 6 given intravenously or orally is very potent in inhibiting platelet aggregation.
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Tsutomu NAKANISHI, Masatoshi NISHI, Akira INADA, Hiroshi OBATA, Nobuka ...
1990 Volume 38 Issue 6 Pages
1772-1774
Published: June 25, 1990
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A known and a new caffeic ester (1 and 2), new inhibitors of xanthine oxidase (XO), were isolated from leaves of Perilla frutescens var. acuta and their structures have been established as (Z, E)-2-(3, 4-dihydroxyphenyl)ethenyl ester (1) and (Z, E)-2-(3, 5-dihydroxyphenyl)ethenyl ester (2) or 3-(3, 4-dihydroxyphenyl)-2-propenoic acid, respectively, based on detailed spectral studies, including 2D COSY, long range COSY, difference NOE, etc. Both caffeic esters strongly inhibited XO in vitro and especially, the inhibition by 1 was as potent as that by allopurinol. The inhibition mode of 1 was also shown to be non-competitive.
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Hisashi ISHII, Tsutomu ISHIKAWA, Sunao TAKEDA, Satoshi UEKI, Masahiro ...
1990 Volume 38 Issue 6 Pages
1775-1777
Published: June 25, 1990
Released on J-STAGE: March 31, 2008
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In the presence of cesium fluoride, the Claisen rearrangement of aryl propargyl ethers selectively provided 2-methylbenzofurans, which was successively treated with osmium tetroxide, periodic acid and 5% sodium hydroxide to give salicylaldehydes in good yields. The method was used to synthesize chelerythrine (2) via the common intermediate (8) prepared by the two routes as shown in Chart 3.
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Kozo HORI, Keiichi NOMURA, Hideki KAZUNO, Eiichi YOSHII
1990 Volume 38 Issue 6 Pages
1778-1780
Published: June 25, 1990
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L-Rhamnal has been transformed into the tetrahydrofuran subunits (14 and 21) of tetronasin (ICI-139603) (1) and tetronomycin (2), in which the three chiral centers at the 2- and 5-positions and the methoxy-bearing carbon are of mirror image.
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Kozo HORI, Keiichi NOMURA, Naotsuka HIKAGE, Eiichi YOSHII
1990 Volume 38 Issue 6 Pages
1781-1783
Published: June 25, 1990
Released on J-STAGE: March 31, 2008
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The polyether fragment 18 of tetronomycin (1) that contains the tetrahydrofuryl and tetrahydropyranyl groups has been synthesized via a Lewis acid-catalyzed coupling of a 2-methoxytetrahydrofuran 16 with a 2-(1-trimethylsilyl-2-propen-1-yl)tetrahydropyran 15.
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Kozo HORI, Shuho MORI, Keiichi NOMURA, Atsushi INAGAKI, Eiichi YOSHII
1990 Volume 38 Issue 6 Pages
1784-1786
Published: June 25, 1990
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An efficient entry to the tetrahydropyran/cyclohexane moiety of tetronasin has been developed. An aldol reaction between a cyclohexanecarboxaldehyde, 8, and a (tetrahydropyranyl)acetate, 9, under controlled conditions followed by dehydration of the adduct 10 afforded predominantly (E)-ester 11, which on photoisomerization and subsequent reduction with iso-Bu
2AlH provided the B/C ring system 13.
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Yasuo FUJIMOTO, Xian-xing ZHANG, Makoto KIRISAWA, Jun UZAWA, Made SUMA ...
1990 Volume 38 Issue 6 Pages
1787-1789
Published: June 25, 1990
Released on J-STAGE: March 31, 2008
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Three new prenylflavones, KB-1 (1), KB-2 (2) and KB-3(3) have been isolated from Indonesian Artocarpus communis FORST. The structures of these flavones were determine by analyses of their
1H-and
13C-NMR spectra including HMBC technique. All these compounds exhibited strong cytotoxic activities against leukemia cells (L-1210) in tissue culture
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Tsutomu OIKAWA, Kenji HIROTANI, Hiroyuki OGASAWARA, Takashi KATAYAMA, ...
1990 Volume 38 Issue 6 Pages
1790-1792
Published: June 25, 1990
Released on J-STAGE: March 31, 2008
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The effects of bleomycin (BLM) and its copper complex on embryonic angiogenesis were studied in the chorioallantoic membranes of 4.5-day-old chick embryos. Copper-free BLM inhibited embryonic angiogenesis in a dose-dependent manner, with activity detectable at 1 ng/egg and maximal at 1000 ng/egg. Also, treatment with copper-BLM complex dose-dependently caused inhibition of embryonic angiogenesis in a lower dose range. Since tumor growth is believed to depend on angiogenesis, the present results may indicate that the antiangiogenic activity of BLM is, at least in part, implicated in the antitumor activity of the drug.
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Miho TANAKA, Nobuharu SHIGEMATSU, Yasuhiro HORI, Toshio GOTO, Masashi ...
1990 Volume 38 Issue 6 Pages
1793-1795
Published: June 25, 1990
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The structure of WS1279 (1__-) isolated from a Streptomyces as an immunoactive lipopeptide has been deduced on the basis of chemical and physical evidence and confirmed by a synthesis.
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Sonoko ARAKI, Sanae EGUCHI, Masuo MORISAKI
1990 Volume 38 Issue 6 Pages
1796-1797
Published: June 25, 1990
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Treatment of 14α, 15α-epoxy-5α-cholestan-3β-ol trimethylacetate (1b) with boron trifluoride etherate in benzene gave the 8-en-15α-ol (2b) in 75% yield, which was then transformed, by oxidation, methylation and deoxygenation, into 14α-methyl-5α-cholest-8-en-3β-ol (7). 24, 25-Dihydrolanosterol (8) was also prepared by these procedures.
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Tsuyoshi SATOH, Jun-ichi SHISHIKURA, Koji YAMAKAWA
1990 Volume 38 Issue 6 Pages
1798-1800
Published: June 25, 1990
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Treatment of α, β-epoxy sulfoxides (sulfinyl oxilanes) with KHF
2 and BF
3·OEt
2 in CHCl
3 gave α-fluoroketones in moderate to good yields.
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