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Keiko TANAKA, Tokuji TAKEDA, Kiyoko FUJII, Koichiro MIYAJIMA
1992 Volume 40 Issue 1 Pages
1-5
Published: January 25, 1992
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The cryoprotective effects of various additives such as saccharides and polyalcohols on sonicated liposomes during freeze-drying were investigated. Fusion of liposomes was measured as energy transfer and size distribution. There was considerable difference among the additives in their cryoprotective ability. Polyalcohol systems showed considerable fusion. Although monosaccharides completely prevented the fusion of liposomes during freeze-drying similarly to disaccharides, they showed far less ability to retain the entrapped calcein of liposomes than disaccharides. The heating thermograms of differential scanning calorimetry of dipalmitoylphosphatidylcholine (DPPC) in the state of sonicated liposomes freeze-dried with various additives were measured. Disaccharides and monosaccharides again markedly differed in their effects on the thermal property of the DPPC. The reason for the variety in their cryoprotective ability was attributed to the difference in the strength of their interaction with phospholipid head group.
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Yuriko YAMAGATA, Ken-ichi TOMITA, Hiroyuki USUI, Akira MATSUDA, Tohru ...
1992 Volume 40 Issue 1 Pages
6-11
Published: January 25, 1992
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Two carbon-bridged cyclodeoxyadenosines, 2'-deoxy-8, 2'-methanoadenosine (8, 2'-MA) and 2'-deoxy-8.2'-ethanoadenosine (8, 2'-EA), were investigated by X-ray and nuclear magnetic resonance (NMR) analyses. Both compounds crystallize in the orthorhombic system with space group P2
12
12
1. The unit-cell dimensions are a=9.427 (1), b=17.287 (2)and c=6.908 (1)Å for 8, 2'-MA and a=15.599(4), b=19.468 (5) and c=9.955 (3) Å for 8, 2'-EA. Both structures were solved by direct methods and refined to R values of 0.037 for 8, 2'-MA and 0.052 for 8, 2'-EA. There are two independent cyclonucleoside molecules and one isopropanol molecule per asymmetric unit in the crystal of 8, 2'-EA. The glycosidec torsion angles, x, O(4')-C(1')-N(9)-C(4), are -68.7 (5)° and -77.2(4)° for molecules (a) and (b) of 8, 2'-EA, respectively, and -65.7(4)° for 8, 2'-MA, and are in high-anti conformation (x; -90°--50°). The deoxyribose ring of 8, 2'-MA takes the C(3')-exo, C(4')-endo twist pucker, and the conformation about the C(4')-C(5') bond is gauche
+.In contrast, both deoxyribose rings of 8, 2'-EA exhibit C(1')-exo envelope puckering, and the conformation about the C(4')-C(5') bond is gauche
+ for molecule (a) and trans for molecule (b).
1H-NMR data indicate that both of the cyclonucleosides in solution exist in the equilibrium of several sugar and exocyclic conformations. 8, 2'-EA adopts two different conformations, even around the glycosidic bound.
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Yasuyuki KITA, Norio SHIBATA, Takashi MIKI, Yumiko TAKEMURA, Osamu TAM ...
1992 Volume 40 Issue 1 Pages
12-20
Published: January 25, 1992
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A stereoselective synthesis of the chiral thienamycin intermediate (16) involving a diastereoselective Michael addition and a silicon-induced Pummerer-type reaction is described. In a similar way, the key intermediate for(+)-PS-5 was also prepared from 4-(phenylsulfinylmethyl)butanamide (21).
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Ryuji YONEDA, Noriko INAGAKI, Shinya HARUSAWA, Takushi KURIHARA
1992 Volume 40 Issue 1 Pages
21-23
Published: January 25, 1992
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Ynone cyanohydrin diethyl phosphates (cyano phosphates) 2 reacted regioselectively with higher-ordr cuprates 3, generated from 2-thienyl(cyano)copper lithium and n-butyl lithium, to give trisubstituted allenic nitriles 4 through an SN2' process in good yields. On the other hand, reaction of an excess of dialkyl copper lithium with ynone cyano phosphates 2 afforded allylic nitriles 5, via allenic nitriles 4.
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Yoshisuke TSUDA, Akiko ISHIURA, Yuki SAKAI, Shinzo HOSOI
1992 Volume 40 Issue 1 Pages
24-31
Published: January 25, 1992
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Reaction of Δ
2-erythrinan derivatives with PhSeCl in methanol gave the following results. The PhSe group was introduced from the β-face (convex face) for 6β-ethoxycarbonyl-7-oxo and Δ
6-7-mesyloxy derivatives (1 and 12), and from the α-face (concave face) for 7α- and 7β-mesyloxy derivatives (16 and 24), while the C-Se bond was always formed at C-3. The structure and stereochemistry of the products were proved by X-ray analyses of the derived 7-O-mesylates (5 and 17). The reasons for the above stereochemical difference and the regiochemical identity were explained by considering the conformational fluctuations in hte ground and transition states of the model compounds a, b, and c based on Chem 3D calculations. These results show that small conformational fluctuations can produce great changes in the stereochemical outcome, particularly in ionic addition reactions.
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Hiromichi FUJIOKA, Hirofumi YAMAMOTO, Hirokazu ANNOURA, Hiroshi MAEDA, ...
1992 Volume 40 Issue 1 Pages
32-35
Published: January 25, 1992
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A new chiral AB-synthon, (5R, 6R)-6-ethyl-5, 6-dihydroxy-5, 6, 7, 8-tetrahydro-1, 4-naphthoquinone (4), for the synthesis of optically active rhodomycinones was prepared stereoselectively from a (-)-α-hydroxy ketone (6). The coupling reactions of 4 with homophthalic anhydride derivatives (9, 12) proceeded in a regioselective manner to give the tetracyclic compounds 10 and 13, respectively. Compound 10 was converted to (-)-γ-rhodomycinone (3) in a two-step sequence. The optical purity (100% ee) of 3 was unambiguously determined by high performance liquid chromatography analysis using a chiral column.
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Takehiro SANO, Jun TODA, Yoshisuke TSUDA
1992 Volume 40 Issue 1 Pages
36-42
Published: January 25, 1992
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The oxyvinylcyclobutanes (2), photoadducts of the dioxopyrrolines (1) to trimethylsilyloxybutadienes, undergo two different types of skeletal rearrangements depending on the reaction conditions. Thermolysis of 2 caused expansion of the cyclobutane ring by a 1, 3-shift of the C
1-C
7 bond toward the vinyl group, giving rise to the hydroindoles (3) in moderate yields. This 1, 3-shift was enormously accelerated when an alkoxide was generated by the action of tetrabutylammonium fluoride (TBAF) on trimethylsilyloxyvinylcyclobutanes. Thus, 2a-d, on treatment with TBAF at -30°C, provided hydroindole derivatives in good yields, though in some cases (2a, b) accompanied with by-products (10). This demonstrates that the [2+2] photoannulation of dioxopyrroline, when coupled with the anionic 1, 3-shift, provides an efficient synthetic route to functionalized hydroindoles. Under acidic conditions, the oxyvinylcyclobutanes(2) rearranged to give exclusively the 2-azatricyclo[4.3.0.0
4, 9]nonanes (10), whose formation was rationalized in terms of the intramolecular Prins-type cyclization with concomitant expansion of the cyclobutane ring by 1, 2-shift of the C
1-C
7 bond toward the vinyl group.
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Akira MIYASHITA, Hideaki MATSUDA, Chihoko IIJIMA, Takeo HIGASHINO
1992 Volume 40 Issue 1 Pages
43-48
Published: January 25, 1992
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When a mixture of 4-chloroquinazoline (7), an aromatic aldehyde 6, sodium hydride, and a catalytic amount of 1, 3-dimethylbenzimidazolium iodide (1) in tetrahydrofuran (THF) was refluxed with stirring for an appropriate time, the chlorine atom of 7 was replaced with the aroyl group, and the 4-aroylquinazolines 10 were obtained in excellent yields. Similar treatments of 4-chloro-2-methylquinazoline (8) and 4-chloro-2-phenylquinazoline (9) led to the 4-aroyl-2-methylquinazolines 11 and the 4-aroyl-2-phenylquinazolines 12, respectively.Use of N, N-dimethylformamide (DMF) instead of THF as the reaction solvent in the above reaction reduced the reaction time and increased the yields of the ketones 10 and 12 as compared with those in THF.
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Magoichi SAKO, Reiko TOTANI, Kosaku HIROTA, Yoshifumi MAKI
1992 Volume 40 Issue 1 Pages
49-52
Published: January 25, 1992
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5, 6, 7, 8-Tetrahydro-8-deaza-8-thiafolic acid (3) was synthesized as a diastereoisomeric mixture via thermal condensation of 5-hydroxyisocytosine (6) with diethyl N-[p-(2-amino-3-mercaptopropyl)aminobenzoyl]glutamate (10)after activation of the C(6)-position in 6 with N-bromosuccinimide/ethanol. The corresponding N
5, N
10-methylene derivative (5) was also prepared upon treatment of 3 with formaldehyde.
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Takashi YOSHIDA, Hideyuki ITOH, Shunyo MATSUNAGA, Reiko TANAKA, Takuo ...
1992 Volume 40 Issue 1 Pages
53-60
Published: January 25, 1992
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Four new hydrolyzable tannins (phyllanthusiins A-D), a new polyphenol of related structure (phyllanthusiin E), and eight known polyphenols have been isolated from the leaves of Phyllanthus flexuosus. On the basis of the spectroscopic methods including
1H-
13C long-range two-dimensional nuclear magnetic resonance techniques, phyllanthusiins A (9), B (12) and C(14), were characterized as oxidative metabolites of geraniin, each having a different new acyl group biogenetically formed via an oxidative cleavage of the dehydrohexahydroxydiphenoyl group, on the
1C
4 glucopyranose core. Phyllanthusiin D (15) was determined to be a condensate of geraniin with acetone, and phyllanthusiin E (16), was an oxidized congener of ellagic acid.
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Yasuyuki KITA, Hiroshi MAEDA, Masayuki KIRIHARA, Yuji FUJII, Toyokazu ...
1992 Volume 40 Issue 1 Pages
61-65
Published: January 25, 1992
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Oxaunomycin (3) and its regioisomer (6) were synthesized by employing regioselective glycosidations of te C-7 hydroxyl group of 10-O-acetyl-β-rhodomycinone (16) and the C-10 hydroxyl group of the C-7, 9-O phenylboronate (14), respectively, in the presence of trimethylsilyl trifluoromethanesulfonate. Under the Konigs-Knorr conditions, 16 was also glycosidated to provide a fluoro sugar analog (7).
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Takashi YOSHIDA, Kumiko HABA, Fumihisa NAKATA, Yoshiaki OKANO, Tetsuro ...
1992 Volume 40 Issue 1 Pages
66-71
Published: January 25, 1992
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Three new hydrolyzable tannin dimers, nobotanins G (6), H (12) and I (13), have been isolated from the leaves of Heterocentron roseum (Melastomataceae), and their structures were elucidated on the basis of chemical degradations and nuclear magnetic resonance spectral analyses. Nobotanin I (13) is a novel dimer possessing a depsidone-forming valoneoyl group in the molecule. Five known tannins, casuarictin (1), strictinin (2), geraniin (3), and nobotanins B (4) and F (5), were also isolated.
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Masaru KOBAYASHI, Madala M. KRISHNA, Keisuke ISHIDA, Vallurupalli ANJA ...
1992 Volume 40 Issue 1 Pages
72-74
Published: January 25, 1992
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Ten 3-oxo-4, 6, 8(14)-triunsaturated steroids with cholestane (1, 2), ergostane (3, 4, 5, 7) and stigmastane skeletons(6, 8, 9, 10), were isolated from a sponge, Dysidea herbacea, collected off the coast of the Lakshadweep Islands, Indian Ocean. Of these, 7 to 10 were obtained as C-24 epimeric mixtures. Compound 2 had previously been reported form a sponge, Dictyonella insica. The hydroperoxide 10 was shown to be an artefact formed from the 24-ethylidene derivative 6 during storage. The structures of 1 to 10 were derived from spectroscopic evidence.
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Tatsuo TSURI, Nobuhiro HAGA, Takeaki MATSUI, Susumu KAMATA, Hisato KAK ...
1992 Volume 40 Issue 1 Pages
75-84
Published: January 25, 1992
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New platelet activating factor (PAF) antagonists, 3 were synthesized by replacing the charged phosphate and trimethylammonium moieties with sulfonamide and heterocyclic quarternary ammonium functionalities, respectively(PAF-sulfonamide isosteres). Darmstoff phosphatidic acid analogues of this class (Darmstoff-sulfonamide isosteres), 6 were also synthesized.The activity of these compounds as PAF antagonists was evaluated from their in vitro inhibitory effect on PAF-induced platelet aggregation in rabbit platelet-rich plasma. Among the compounds tested, some of the 2-methoxypropane derivatives with an octadecylcarbamoyloxy or octadecylcarbamoylthio side chain at the 1-position and a propylsulfonamide function bearing a terminal polar substituent such as a quarternary quinolinium or substituted quinolinium group at the 3-position were found to be the most potent (IC
50=0.3-0.6μM).
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Tatsuo TSURI, Takeaki MATSUI, Nobuhiro HAGA, Susumu KAMATA, Sanji HAGI ...
1992 Volume 40 Issue 1 Pages
85-95
Published: January 25, 1992
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In a continuing effort to obtain more potent platelet activating factor (PAF) antagonists, we tried to synthesize a series of PAF-sulfonamide isosteres in which the substituent at the 2-position was modified to an acetoxy equivalent other than the methoxy group. These modifications produced highly active PAF antagonists. Compound 3-[2-(5-methyl 2H-tetrazol-2-yl)-3-(octadecylcarbamoyloxy)propylaminosulfonyl]propylquinolinium iodide (52) showed the most potent activity in the in vitro inhibitory effect on PAF-induced platelet aggregation in rabbit platelet-rich plasma (IC
50=125nM) and also in the in vivo protective effect on PAF-induced lethality in mice, with prolonged duration of action. Optically active enantiomers of this compound were synthesized and the (S)-(-)-isomer (IC
50=87nM) was found to be three times more potent that the (R)-(+)-isomer (IC
50=289nM), clearly exemplifying the enantioselectivity in the PAF-antagonist action of this novel compound.
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Shogo MARUI, Fumio ITOH, Yoshio KOZAI, Katsuichi SUDO, Shoji KISHIMOTO
1992 Volume 40 Issue 1 Pages
96-101
Published: January 25, 1992
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The hydroxy group of fumagillol (3), a degradation product of fumagillin (1), was acylated, sulfonylated, alkylated or carbamoylated, and the anti-angiogenic activity of the resulting products was examined. These compounds inhibited the angiogenesis induced by basic fibroblast growth factor in the rat corneal micropocket assay and the growth of vascular endothelial cells in vitro. Among them, compound 2 (AGM-1470) was found to show the most potent inhibitory effect on the growth of vascular endothelial cells and was selected form this series as a candidate for further development.
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Hiroyoshi YAMAZAKI, Hiroshi HORIKAWA, Takashi NISHITANI, Tameo IWASAKI ...
1992 Volume 40 Issue 1 Pages
102-108
Published: January 25, 1992
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2, 2, -Disubstituted norbornenes (1, 2), 2, 2-Disubstituted norbornane (3), 2, 2, 3-trisubstituted norbornenes (4, 5), oxanorbornenes (6) and azanorbornenes (7) were synthesized by the Diels-Alder reaction using α, β-dehydroamino acids as a key step, and their antiulcer activities were examined. The oxazolidine derivative (1h) exhibited the most potent activities against several ulcer-models in rat.
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Haruhiko SATO, Takashi DAN, Etsuro ONUMA, Haruko TANAKA, Bunya AOKI, H ...
1992 Volume 40 Issue 1 Pages
109-116
Published: January 25, 1992
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A series of substituted 1, 3-dioxolo[4, 5-f]-1, 2-benzisoxazole-6-carboxylic acids 13 and 1, 3-dioxolo[4, 5-g]-1, 2-benzisozazole-7-carboxylic acids 14 were synthesized and evaluated for diuretic and uricosuric activities in rats. Most of the benzisoxazole derivatives 13 and 14 showed potent diuretic activities. Moderate uricosuric activities were also found in 14a, 14b, and 14f.
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Tohru NAKAO, Minoru OBATA, Yuko YAMAGUCHI, Nobuhiro MARUBAYASHI, Kunik ...
1992 Volume 40 Issue 1 Pages
117-121
Published: January 25, 1992
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Two enantiomers of 2-(4-chlorophenyl)-5, 6-dihydro-(1)benzothiepino[5, 4-c]pyridazin-3(2H)-one 7-oxide ((±)-1 : Y-23684) were synthesized in high yields by asymmetric oxidation of the synthetic precursor (2) using modified Sharpless reagent. Among the oxidants tested, cumene hydroperoxide (CHP) gave the highest optical and chemical yields, while tert-butyl, tert-amyl, and 1, 1, 3, 3-tetramethylbutyl hydroperoxides did not show such high enantio-selectivities. The absolute configuration of (+)-1 enantiomer synthesized form 2, Ti(O-iso-Pr)
4, (-)-diethyl tartarate, and CHP was determined to be S by X-ray crystallographic analysis. Both enantiomers, S-(+)-1 and R-(-)-1, and (±)-1 had approximately equivalent in vivo activities to antibicuculline test in mice and anticonflict test in rats, although S-(+)-1 showed about three times higher affinity to benzodiazepine receptor than R-(-)-1 in [
3H]diazepam binding assay.
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Tameo IWASAKI, Hiroyoshi YAMAZAKI, Takashi NISHITANI, Kazuhiko KONDO, ...
1992 Volume 40 Issue 1 Pages
122-126
Published: January 25, 1992
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A series of 2-aminoethanol derivatives was synthesized and their inhibitory activities against protein kinase C were investigated. Among these compounds, 2-endo-hexadecylamino-5-norbornene-2-exo-methanol (4h) and 2-endo-hexadecylamino-5-norbornene-2, 3-exo-dimethanol (4i) inhibited protein kinase C at the IC
50 values of 2×10
-5 and 1×10
-5 M, respectively, but not protein kinase A at a concentration of 1×10
-3 M. The structure-activity relationships are discussed.
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Ikuo MORIGUCHI, Shuichi HIRONO, Qian LIU, Izumi NAKAGOME, Yasuo MATSUS ...
1992 Volume 40 Issue 1 Pages
127-130
Published: January 25, 1992
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A simple method of calculating log P (partition coefficient in octanol/water) has been developed based on the quantitative structure-log P relationship for 1230 organic molecules having a wide variety of structures. The 1230 organic compounds investigated included general aliphatic, aromatic, and heterocyclic molecules together with various drugs and agrochemicals. The predictive structure-log P model obtained by multiple regression analysis involved only 13 parameters for hydrophobic atoms, hydrophilic atoms, their proximity effects, unsaturated bonds, amphoteric property, and several specific functionalities. A saturation effect was recognized in the parameters for hydrophobic and hydrophilic atoms, and unsaturated bonds. The structure-log P relationship was highly significant as the F-statistics=900.4. This simple method appears accurate enough for semiquantitative uses in structure-activity rating studies, especially for quantitative structure-activity relationship in toxicity.
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Takashi YAEGASHI, Ken-ichiro NOKATA, Seigo SAWADA, Tomio FURUTA, Teruo ...
1992 Volume 40 Issue 1 Pages
131-135
Published: January 25, 1992
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Water-soluble derivatives having the lactone ring intact were synthesized starting from 7-ethyl-10-hydroxycamptothecin (1). Glycosides (2) of the phenolic hydroxyl group of 1 were obtained by reaction with acetylated α-bromosugars in acetone or aqueous acetone in the presence of potassium carbonate, followed by deprotection.Phosphates (3) were prepared by reaction of 1 with phosphoryl chloride in pyridine or with dibenzylchlorophosphoridate.Sulfates (4) were obtained by reaction of 1 with sulfur trioxide-pyridine complex in the presence of a tertiary amine.The organic ammonium salts of monophosphate (3p) and sulfates (4a and 4b) showed significant activity against L1210 in vivo.
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Baoliang CUI, Yusuke SAKAI, Takashi TAKESHITA, Junei KINJO, Toshihiro ...
1992 Volume 40 Issue 1 Pages
136-138
Published: January 25, 1992
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Four new methyl ester derivatives of oleanene glycosides (3-6) were isolated from the seeds of Astragalus complanatus R. BR. together with two known triterpene glycosides, astragaloside VIII methyl ester (1) and soyasaponin I methyl ester (2) after treatment with diazonethane during separation procedure. The structures of 3-6 were elucidated as 3-O-α-L-rhamnopyranosyl(1→2)-β-D-xylopyranosyl(1→2)-6-O-methy-β-D-glucuronopyranosyl-soyasapogenol B 22-O-β-D-glucopyranosede, 3-O-α-L-rhamnopyranosyl(1→2)-β-D-galactopyranosyl(1→2)-6-O-methyl-β-D-glucuronopyranosyl-soyasapogenol B 22-O-β-D-glucopyranoside, 3-O-α-L-rhamnopyranosyl(1→2)-β-D-xylopyranosyl(1→2)-6-O-methyl-β-D-glucuronopyranosyl 3β, 22β, 24-trihydroxy-11-oxo-olean-12-ene and 3-O-α-L-rhamnopyranosyl (1→2)-β-D-galactopyranosyl(1→2)-6-O-methyl-β-D-glucuronopyranosyl 3β, 22β, 24-trihydroxy-11-oxo-olean-12-ene, respectively.
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Yi DING, Takashi TAKESHITA, Kei YOKOYAMA, Junei KINJO, Toshihiro NOHAR ...
1992 Volume 40 Issue 1 Pages
139-142
Published: January 25, 1992
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Three new oleanene glycosides named subprosides I-III (1-3) were isolated as the corresponding methly ester forms together with four known glucuronide saponins, soyasaponin II (4), dehydrosoyasaponin I (5), kudzusaponin A
3(6) and abrisaponin I (7), from Sophorae Subprostratae Radix, the roots of Sophora subprostrata CHUX et T. CHEN(Leguminosae). The structures of subprosides I-III were characterized as 3-O-α-L-thamnopyranosyl(1→2)-β-D0-glactopyranosyl (1→2)-β-D-glucuronopyranosyl-abrisapogenol C (1), 3-O-α-L-thamnopyranosyl(1→2)-α-L-arabinopyranosyl (1→2)-β-D-glucuronopyranosyl-kudzusapogenol A (2) and 3-O-α-Lrhamnopyranosyl(1→2)-β-D-galactopyranosyl(1→2)-β-D-glucuronopyranosyl-wistariasapogenol A 30-O-β-D-glucopyranodide (3) by the chemical and spectral evidence.
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Takatomi OHSAWA, Masae YUKAWA, Chusei TAKAO, Mitsuo MURAYAMA, Hideo BA ...
1992 Volume 40 Issue 1 Pages
143-147
Published: January 25, 1992
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From the crude drug Chorei, the fruit body of Polyporus umbellatus, seven new components named polyporusterone A, B, C, D, E, F and G, were isolated and their structures were determined on the basis of the spectral data. These compounds showed cytotoxic action on leukemia 1210 cell proliferation.
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Yoshihiro MIMAKI, Yutaka SASHIDA, Kazuhiro KAWASHIMA
1992 Volume 40 Issue 1 Pages
148-152
Published: January 25, 1992
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Seven new steroidal compounds were isolated from the fresh bulbs of Camassia cusickii S. WATS. Their structures were detemined by spectroscopic analysis and hydrolysis to be (25R)-5α-spirostan-3β, 6α-diol (chlorogenin) 6-O-β-D-xylopyranosyl-(1→3)-β-D-glucopyranoside (1), chlorogenin 6-O-β-D-xylopyranosyl-(1→2)-O-[β-D-glucopyranosyl-(1→3)]-β-D-glucopyranoside (2), chlorogenin 6-O-β-D-glucopyranosyl-(1→2)-O-[β-D-xylopyranosyl-(1→3)]-β-D-glucopyranoside (3), chlorogenin 6-O-β-D-fucopyranosyl-(1→2)-O-[β-D-glucopyranosyl-(1→3)]-β-D-glucopyranoside(4), 22-O-methyl-26-O-β-D-glucopyranosyl-(25R)-5α-furostan-3β, 6α, 22ξ-triol 6-O-β-D-glucopyranosyl-(1→3)-β-D-glucopyranoside (5), 22-O-methyl-26-O-β-D-glucopyranosyl-(25R)-5α-furostan-3β, 6α, 22ξ-tiol 6-O-β-D-glucopyranosyl-(1→2)-O-[β-D-glucopyranosyl-(1→3)]-β-D-glucopyranoside (6) and 3β, 7β, 16β-trihydroxycholest-5en-23-one 3, 16-bis-O-β-D-glucopyranoside (camassioside)(7).
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Akira SANO, Naoto ENDO, Shoji TAKITANI
1992 Volume 40 Issue 1 Pages
153-156
Published: January 25, 1992
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Nicotinamide (NA) and its four isomeric methyl analogs [2-, 4-, 5- and 6-methylnicotinamides (MNs)] were tested as substrates for nicotinamide N-methyltransferase (NNMT) and amine N-methyltransferase (ANMT) using rat liver, kidney, spleen and brain 9000×g supernatant fluids as model enzyme preparations. The N-methylated products were determined fluorometrically by their reaction with acetophenone or 4-methoxybenzaldehyde to form fluorescent 2, 7-naphthyridine derivatives, and the lower limits of the determination were 8-30 pmol/100μl. N-Methyltransferase activities were detected in the liver with NA, 4-MN and 5-MN, and in the brain and spleen with 4-MN. On this basis, 5-MN is considered to be a selective substrate for NNMT in addition to NA, which is a known methyl acceptor for this enzyme. Although 4-MN appears to serve as a methyl acceptor for both ANMT and NNMT, it seems to be essentially a selective substrate for brain ANMT because of the absence of NNMT in brain. The fluorometric methods used here are also very useful because of their simplicity, sensitivity and selectivity.
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Kyoichiro HIGASI, Hiroshi OGAWARA
1992 Volume 40 Issue 1 Pages
157-160
Published: January 25, 1992
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The effect of isoflavone compounds, genistein and daidzein, on the breakdown of inositol phospholipids in 3T3 cells was studies. Genistein (100μg/ml) inhibited the sitmulation of the production of inositol phosphates by bombesin. The stimulated production of inositol phosphates by AlF
-4 was also inhibited by genistein (IC
50=0.6μg/ml)and daidzein (IC<50>=2μg/ml). However, the catalytic activity of phospholipase-C (PLC) in 3T3 cell extracts was not inhibited by these isoflavones. These results suggest that the isoflavones inhibited the activation of PLC at the G-protein or downstream of the sequences in signal transduction.In permeabilized 3T3 cells, the inhibition of AlF
-4 plus adenosine triphosphate (ATP)-dependent PLC was recovered by increasing ATP but not AlF
-4. Genistein also inhibited the activity of adenosin 5'-[3-O-thiotriphosphate](ATP[S])-dependent PLC. The effect of genistein and other inhibitors of protein tryrosine kinases and phosphatases suggests that protein tyrosine phosphorylation is not involved in the activation of PLC in 3T3 cells and that AlF
-4-and ATP[S]-mediated activation of PLC involves a different mechanism from the tyrosine kinase-mediated activtion of PLC.Daidzein and genistein seem to interrupt the ATP-dependent step of PLC activation by a putative G-protein.
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Hideo SAJI, Yuji KUGE, Yasuhiro MAGATA, Yasuhisa FUJIBAYASHI, Akira YO ...
1992 Volume 40 Issue 1 Pages
161-164
Published: January 25, 1992
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To develop radiopharmaceuticals for pancreatic imaging, radioiodinated ethyl benzene derivatives contaning various functional groups (amino, carboxyl, and methyl groups) were synthesized and the effects of these functional groups were compared in vitro and in vivo. At 2 min after intravenous injection, the amino derivative, 2-(4-iodophenyl)-N, N-dimethyl ethylamine, displayed about twice the pancreatic uptake and a more than 8-fold higher pancreas/liver ratio than the carboxyl and methyl derivatives. This high and selective in vivo accumulation on the amino derivative in the pancreas was well supported by in vitro studies on the uptake by pancreatic tissue slices. The mechanism promoting pancreatic accumulation of radiopharmaceuticals with an amino group is also discussed.
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Hideo SAJI, Taro TOKUI, Iwao NAKATSUKA, Akihiko SAIGA, Yasuhiro MAGATA ...
1992 Volume 40 Issue 1 Pages
165-169
Published: January 25, 1992
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A series of radioiodinated spiperone (2'-ISP) derivatives bearing amide N-alkyl substituents (N-methyl-2'-ISP, N-ethyl-2'-ISP, and N-propyl-2'-ISP) were synthesized and evaluated as potential singlet photon emission computed tomographic radiopharmaceuticals for visualizing dopaminergic receptors. The lipophilicity of these ligands (i.e., the partition coefficient for octanol-phosphate buffer) increased as the chain length increased. Investigation of blood-brain barrier permeability in rats showed a parabolic relationship between the brain uptake index and the partition coefficient.In vitro competitive binding studies showed that the relative affinity for the dopamine D
2 receptor was in te order of N-propyl-2'-ISP>2'-ISP>N-methyl-2'-ISP≈N-ethyl-2'-ISP. In vivo biodistribution studies showed that the initial brain uptake correlated fairly well with the brain uptake index and that the kinetics of the radioactivity specifically bound to the striatum were strongly influenced by the dopamine receptor binding affinity of the compounds. Thus, the in vivo behavior of these N-alkylated 2'-ISP derivatives involved a complex interplay between receptor affinity, lipophilicity, and blood-brain barrier permeability.
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Kenji AKASAKI, Hiroko KINOSHITA, Masataka FUKUZAWA, Makoto MAEDA, Yasu ...
1992 Volume 40 Issue 1 Pages
170-173
Published: January 25, 1992
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We have purified and characterized a novel glycoprotein (r-lamp-3) with an apparent molecular weight (M
r) of 85000 from membranes of triton-filled lysosomes (tritosomes) by the use of immunoaffinity chromatography on a column of monoclonal antibody-Sepharose 4B. r-lamp-3 accounted for approximately 4% of the total proteins in tritosomal membranes. The isoelectric point (pI) of r-lamp-3 was 4.5 and it was shifted to 6.5 after neuraminidase treatment with its molecular weight decreased by about 7000. Pulse-chase experiments in cultured rat hepatocytes using [
35S]methionine showed that r-lamp-3 was initially synthesized as a 77000 polypeptide and processed to a mature protein with an M
r of 85000. Upon treatment with endo-β-N-acetylglucosaminidase H (Endo H), the precursor and mature forms were converted to 55000 and 73000 polypeptides, respectively. From the M
r reduction of the precursor form, we estimated the presence of 10-12 N-linked oligosaccharides/r-lamp-3 polypeptide. The data on enzymatic deglycosylation suggested that the mature form of r-lamp-3 contained the same numbers of high mannose-tyep and complex-type N-linked oligosaccharide chains.
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Takayuki FUNAKOSHI, Hideaki SHIMADA, Shoji KOJIMA, Shozo SHOJI, Yukiho ...
1992 Volume 40 Issue 1 Pages
174-176
Published: January 25, 1992
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Sodium orthovanadate (vanadate) prolonged the colotting time of normal human plasma in a dose-dependent manner. The prolongation of clotting time by vanadate linearly decresed with an increase in the concentration of amiloride. Vanadate also was completely additive to prolongation by heparin. When factor Xa or thrombin was incubated with vanadate, the amidolytic activity of each decreased in a dose-dependent manner with vanadate.Amiloride protected the decrease of amidolytic activity of both factor Xa and thrombin by vanadate. The amidolytic activity of trypsin also was inhibited by vanadate, but that of α-chymotrypsin was not inhibited, suggesting that vanadate preferentially inhibits the amidolytic activity of trypsin and trypsin-like enzymes. These results show that vanadate prolongs the clotting time of plasma through mechanisms involving in part the inhibition of the activity of both factor Xa and thrombin.
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Yasuhisa TAKEDA, Kazumi URAKAWA, Akemi SAKAMOTO, Toshiaki NAKANO, Yuta ...
1992 Volume 40 Issue 1 Pages
177-181
Published: January 25, 1992
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The regulatory effects of lobenzarit disodium (CCA), a therapeutic agent for treating rheumatoid arthritis (RA), on polyclonal immunoglobulin production by human lymphocytes were investigated in vitro. CCA inhibited the production of immunoglobulin in all the classes examined at a clinically relevant concentration. Moreover, it inhibited the immunoglobulin production as well as lymphocyte proliferation even when purified B lymphocytes preactivated by Staphylococcus aureus COWAN I were cultured with recombinant lymphokines such as IL2 and IL6. These results suggest that CCA acts directly on B lymphocytes.The anaysis at each of two different stages of B lymphocyte activation lineage, i.e., the primary activation stage and a stage of proliferation and differentiation to antibody secreting cells, has indicated that CCA inhibits the proliferation-differentiation stage of B lymphocytes. CCA does not inhibit B lymphocytes at the primary activation stage; actually, it augments them, resulting in the subsequent enhancement of immunoglobulin production.
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Yoshihiro SATO, Yumiko SAKAKIBARA, Taiko ODA, Eriko AIZU-YOKOTA, Ken I ...
1992 Volume 40 Issue 1 Pages
182-184
Published: January 25, 1992
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The effects of estradiol (E
2) and ethynylestradiol (EE
2) on the chromosome number and cellular microtuble architecture of Chinese hamster V79 cells were studied using fluorescent anti-tubulin antibody. Treatment with 20μM E
2 for 48h induced only a small amount of tetraploid cells, but the normal microtubule network was disrupted completely by only 3h of treatment.This data reveals that E
2 has higher microtubule-disruptive activity than diethylstilbestrol in V79 cells.
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Ryoko GONDA, Kenji TAKEDA, Noriko SHIMIZU, Masashi TOMODA
1992 Volume 40 Issue 1 Pages
185-188
Published: January 25, 1992
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A neutral polysaccharide, named ukonan D, was isolated from the rhizome of Curcuma longa L. It produced a single hand on electrophoresis and a single peak on gel chromatography, and its molecular mass was estimated to be 28000. It showed remarkable reticuloendothelial system-potentiating activity in a carbon clearance test. Ukonan D is composed of L-arabinose : D-galactose : D-glucose : D-mannose in the molar ratio of 1 : 1 : 12 : 0.2, in addition to small amounts of peptide moiety. Methylation analysis, carbon-13 nuclear magnetic resonance and enzymic degradation studis indicated that its structural features include mainly both α-1, 5-linked L arabino-β-3, 6-branched D-galactan type and α-4, 6-branched D-glucan type structural units. The influence of degradation with α-amylase followed by the elimination of glucan side chains on its immunological activity was discussed.
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Kotaro IIDA, Akinobu OTSUKA, Kazumi DANJO, Hisakazu SUNADA
1992 Volume 40 Issue 1 Pages
189-192
Published: January 25, 1992
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Adhesion between glass beads and polymer films was investigated using the centrifugal separation method at various relative humidities. The adhesive force depended on the type of polymer, and it was found that there was a close correlation between the adhesive force and teh amount of water sorbed by the polymer film. This finding suggests that the polymer surface becomes softened by hte sorbed water; consequently, the contact area between a particle and the polymer film increases. The surface treatment of glass beads with trimethylchlorosilane reduced the adhesive property of the particle in every system.
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Masahiko KIMURA, Naomi TANAKA, Yasuhiro KIMURA, Katsusi MIYAKE, Teruak ...
1992 Volume 40 Issue 1 Pages
193-195
Published: January 25, 1992
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The relationship between daily dose and serum concentration of zonisamide (ZNS) and the effects of patient age on the serum level/dose (L/D) ratio for ZNS were studied in epileptic patients (mean age ±S.D.=10.6±6.2years)who chronically received ZNS. The influence of phenytoin (PHT), phenobarbital (PB), carbamazepine (CBZ) and valproic acid (VPA) on the serum protein binding of ZNS in vitro and the correlation between total and unbound serum levels of ZNS in partients were also examined. Significant correlations were obtained between daily dose per body weight or per body surface area and serum level of ZNS. The correlation coefficient of the latter was higher than that of the former. There was no effect of age on the L/D ratio on the basis of body surface area, whereas that on the basis of body weight increased significantly with age. No significant increase in the free fraction of ZNS was observed in the presence of PHT, PB and CBZ except VPA in vitro. There were significant correlations between total and unbound serum levels of ZNS in the two patient groups coadministered with and without VPA. Although the free fraction of ZNS in the former was significantly higher than that of the latter, the increase was small. These results suggest that dosage regimens on the basis of body surface area would be more accurate than those on a body weight basis and that there is little effect of other antiepileptics on the serum protein binding of ZNS.
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Yoshiaki KAWASHIMA, Toshiyuki NIWA, Hirofumi TAKEUCHI, Tomoaki HINO, Y ...
1992 Volume 40 Issue 1 Pages
196-201
Published: January 25, 1992
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Prolonged-release spherical micro-matrices of ibuprofen with Eudragit RS were prepared using a novel emulsion-solvent diffusion method. Those particles were termed "microsponges" due to their characteristic sponge-like texture and unique dissolution and compression properties, unlike conventional microcapsules or microspheres. The internal porosity of microsponges could be easily controlled by changing the concentration of the drug and the polymer in the emulsion droplet(ethanol). With lower concentration of ibuprofen in the ethanol, the resultant microsponges had a higher porosity, about 50%. The drug release rate from the microsponges was interpreted by the Higuchi model of spherical matrices, which depended only on their internal porosity of the microsponges when size distribution and drug content were the same. The tortuositles in the microsponges were found to be almost constant (3-4) irrespective of porosity, suggesting the same internal texture. Microsponge compressibility was much improved over the physical mixture of the drug and polymer owing to the plastic deformation of their sponge-like structure. The more porous microsponges produced stronger tablets.
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Jun SAKAGUCHI, Hiroyuki NISHINO, Nobuo OGAWA, Yuji IWANAGA, Shingo YAS ...
1992 Volume 40 Issue 1 Pages
202-211
Published: January 25, 1992
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Nobel N-[[2-(dialkylamino)ethoxy]benzyl]benzamide derivatives (II-1-51), derived form the structural modification of metoclopramide (i), were synthesized and examined for their pharmacological activities. Among them, N-[4-[2-(dimethylamino)ethoxy]benzyl]-3, 4-dimethoxybenzamide (II-34) which exhibited well balanced gastrointestinal prokinetic and antiemetic activities was selected as a new type of gastrointestinal prokinetic agent.
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Kazumi MORIKAWA, Tomoko MATSUMOTO, Yukio MATSUOKA, Kinya KOIZUMI
1992 Volume 40 Issue 1 Pages
212-219
Published: January 25, 1992
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The interactions of a new antitumor platinum (Pt) complex, (-)-(R)-2-aminomethylpyrrolidine(1, 1-cyclobutanedicarboxylato)platinum(II) monohydrate (DWA2114R, 2) and its related compounds, cis-diamminedichloroplatinum(II)(CDDP, 2), trans-diamminedichloroplatium(II)(TDDP, 3), (+)-(S)-2-aminomethylpyrrolidine(1, 1-cyclobutanedicarboxylato)platinum(II) monohydrate (DWA2114S, 4), (R)-2-aminomethylpyrrolidinedichloroplatinum(II)(5) and cis-diammine(1, 1-cyclobutanedicarboxylato)platinum(II)(CBDCA, 6), with calf-thymus deoxyribonucleic acid (DNA)and DNA nucleosides were investigated by ultraviolet (UV) and circular dichroism (CD) spectrometry.The UV spectra of the DNAs treated with these Pt complexes exhibited both bathochromic shift and hyperchromicity, showing a binding of Pt to the heterocyclic groups of these DNA as well as an alteration in the secondary structure of DNA. The reaction rates of the Pt complexes with DNA, however, differed from one another, and the order was CDDP, TDDP, 5»DWA2114R, S>CBDCA.The CD spectra of the DNAs treated with the Pt complexes, except TDDP, at a low Pt ratio (<approximately(ca.)0.1 of Pt bound to DNA/DNA base molar ratio) exhibited an increase of ellipticity at ca. 275nm.The melting temperature of the DNAs treated with DWA2114R of CDDP were almost the same as the native DNA, while the melting temperature with TDDP was higher by 7-8°C than that of the native DNA.All the Pt complexes reacted with 2'-deoxyguanosine (dG), 2'-deoxyadenosine and 2'-deoxycytidine, but none reacted with thymidene. The CD spectral change of the dG was largest. DWA2114R reacted faster with dG than other mucleosides.
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Nobuhiro MARUBAYASHI, Takayuki OGAWA, Minoru MORIWAKI, Mamoru HARATAKE
1992 Volume 40 Issue 1 Pages
220-223
Published: January 25, 1992
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3-Aminomethyl-4-[3-o-chlorobenzoyl)-5-ethylthiophen-2-yl]-5-methyl-4H-1, 2, 4-triazole (I), the hydrolytically ring-opened derivative of etizolam, which is one of the 1, 4-diazepine antianxiety drugs, was investigated from the stereochemical point of view. In order to isolate atropisomeras of compound I, its carbonyl group was reduced to a chiral secondary alcohol. The resulting compounds were resolved successfully into two comonents (IIa and IIb) by silica-gel column chromatography. The structures of atropisomeric IIa and IIb. possessing rotational differences about the single bond between the thiophene and triazole rings, were confirmed by X-ray crystallographic analysis. The interconversion behavior between them was also examined.
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Hideo TAKEDA, Kiyoshi INOGUCHI, Shunji SAKURABA, Kazuo ACHIWA
1992 Volume 40 Issue 1 Pages
224-226
Published: January 25, 1992
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The N-substituent effect on the enantioselectivity and the catalytic activity of the rhodium complexes of pyrrolidinebisphosphine ligands, PPMs and CPMs, was examined by means of hydrogenation studies and
31P-nuclear magnetic resonance spectral analysis.
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Ken-ichi TANZI, Ranko SATOH, Takeo HIGASHINO
1992 Volume 40 Issue 1 Pages
227-229
Published: January 25, 1992
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The condensation of a methyl group at the 6- of 8-position on the 9H-purine ring with benzaldehyde and ethyl benzoate in the presence of sodium hydride occurred to give the styryl- (4a, b) and phenacyl-9H-purines (5a, b and 6a, b). Conversion of the metyl group into a formyl group was achieved by treatment with selenium dioxide in dioxane, giving the 9H-purinecarboxaldehydes (7a, b and 8a, b).
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Chihiro ITO, Norio OKAHANA, Tian-Shung WU, Meei-Ling WANG, Jeng-Shiow ...
1992 Volume 40 Issue 1 Pages
230-232
Published: January 25, 1992
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Two new monomeric and one dimeric carbazole alkaloids were isolated from root bark of Murraya euchrestifolia HAYATA collected in Taiwan. Their structures were elucidated by spectrometric and synthetic studies. The structures of the monomeric carbazoles were assigned as 3-formyl-7-hydroxy-9H-carbazole (1) and N-methoxy-3-hydroxymethyl-9H-carbazole (2). The dimeric carbazole, named chrstifoline-D (9), was found to be identical with the oxidation product of bismurrayafoline-A (10).
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Masaru KOBAYASHI, Bodepudi HARIBABU, Vallurupalli ANJANEYULU
1992 Volume 40 Issue 1 Pages
233-234
Published: January 25, 1992
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The lipid extract of the Sclerophytum so. of soft coral, collected off the coast of the Andaman and Nicober Islands, afforded a new sterol 1a. The structure of 1a was shown to be (24S)-3β-hydroxyergost-5-en-21-oic acid, the first member of a class of marine sterols having a C-21 carboxylic acid, by spectral analyses and conversion to(24S)-ergostane.
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Magoichi SAKO, Reiko TOTANI, Kosaku HIROTA, Yoshifumi MAKI
1992 Volume 40 Issue 1 Pages
235-237
Published: January 25, 1992
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Treatment of ethenylated isocytosines, imidazolo[1, 2-α]pyrimidine-5(1H)-one (2) and -7(8H)one (3), with lead tetraacetate (LTA) in glacial acetic acid followed by alkaline hydrolysis resulted in the smooth removal of the ethenyl group to give isocytosine (1) in high yields. The unmasking of 2 by LTA to 1 was compared with the results using iodosylbenzone diacetate and N-bromosuccinimide.
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Toru SUGAYA, Yukihiro KUGE, Shinji TOMIOKA, Kentaro TAMAKI
1992 Volume 40 Issue 1 Pages
238-239
Published: January 25, 1992
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A new antiallergic agent with thromboxane A
2 antagonistic activity, KW4099, was synthesized by a simple method.Its optical resolution was accomplished with the use of (+)- or (-)-2, 2'-(1, 1'-binaphthyl)phosphoric acid as a resoliving agent.
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Kiyoshi TANIGUCHI, Yousuke KATSURA, Ikuo UEDA, Masaaki MATSUO
1992 Volume 40 Issue 1 Pages
240-244
Published: January 25, 1992
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For improvement of the duration of action of FR35447 (I), 2-(biphenylimino)imidazolidines (III) were synthesized and their hypotensive activity was tested against conscious normotensive rats. 2-(4'-Fluoro-[1, 1'-biphenyl]-2-ylimino)imidazolidine (III l) exhibited superior hypotensive potency and was comparable to clonidine (II) in its duration of action.The structure-activity relationships of III are also described.
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Naoko MIYAHARA, Yoko KASUGAI, Yoshiro OHMOMO, Chiaki TANAKA, Tsuyoshi ...
1992 Volume 40 Issue 1 Pages
245-248
Published: January 25, 1992
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Various analogues of benzyl 5-phenyl-2-oxazolecarbamate (1a) were synthesized, and the structure-activity relationship of these analogues as aldose reductase inhibitor was studied. The carbamate group was necessary for the inhibitory activity. The introduction of an alkyl group at the C-4 position of 1a enhanced the inhibitory activity, however, the N-carboxymethyl group on the carbamate moiety counteracted to a hydrophobic interaction between the alkyl group at the C-4 position and the enzyme molecule.
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Susumu KITANAKA, Michio TAKIDO
1992 Volume 40 Issue 1 Pages
249-251
Published: January 25, 1992
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Two new flavone glycosides were isolated along with diosmetin, luteolin, and luteolin 7-O-glucoside, from the leaves of Cassia torosa CAV., and their structures were established as diosmetin 3'-O-β-D-glucopyranoside (1) and torosaflavone B 3'-O-β-D-glucopyranoside (2) (diosmetin 6-C-β-D-oliopyranosyl-3'-O-β-D-glucopyranoside) on the basis of spectroscopic and chemical evidence.
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