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Hiroaki KOMATSU, Tetsurou HANDA, Koichiro MIYAJIMA
1994 Volume 42 Issue 9 Pages
1715-1719
Published: September 15, 1994
Released on J-STAGE: March 31, 2008
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The proportions of phosphatidylcholine (PC) molecules forming liposomes and the monolayer of emulsion particles in sonicated dimyristoyl or egg yolk PC/triolein dispersions (emulsions) were estimated by fluorescence quenching, using phosphatidylethanolamine with its hydrophilic group labelled with a fluorescent dansyl group, and by the
1H-NMR signal shift of the choline-methyl proton of PC using a paramagnetic shift agent. From a comparison of the values estimated by the fluorescence and
1H-NMR methods, it was concluded that the fluorescence method slightly underestimates the proportion of PC molecules in liposomes but can be effectively used to estimate the liposomal content of lipid dispersions due to the sensitivity and the relative simplicity of the basic methodology and instrumentation.
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Nobuo KAWAHARA, Setsuko SEKITA, Motoyoshi SATAKE, Shun-ichi UDAGAWA, K ...
1994 Volume 42 Issue 9 Pages
1720-1723
Published: September 15, 1994
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Two new compounds, designated nidulalins A (1) and B (2), were isolated along with emestrin and sterigmatocystin from the extract of rice culture of Emericella nidulans var. lata. The structures of nidulalins A (1) and B (2) were determined on the basis of chemical and spectroscopic investigation and X-ray crystallographic study, together with the application of the modiifed Mosher's method.
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Takashi MICHIDA, Yukako KASUYA, Michiko NISHIYAMA, Hiroteru SAYO
1994 Volume 42 Issue 9 Pages
1724-1729
Published: September 15, 1994
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Controlled potential electrolysis (CPE) of meso-tetraphenylporphyrinatomanganese (III) chloride (1mM, 1a) at -0.4V (vs. saturated calomel electrode (SCE) in acetonitrile containing diphenyl sulfide (100mM, 2), 1-methylimidazole (5mM), and tetrabutylammonium perchlorate (0.1M) as supporting electrolyte with a reticulated vitreous carbon (RVC) cathode and bubbling O
2 gas, gave diphenylsulfoxide (12.6%-16.4%, 3) and diphenylsulfone (0.5%-1.5%, 4) in the presence of acetic acid/or tetramethylammonium hydroxide (5). In the absence of acetic acid or 5, compound 2 was not oxidized. The results of cyclic voltammetry and CPE at -0.4V (vs. SCE) showed that the oxidant of 2 was an oxo-manganese (V) species which was generated from 1a and dissolved dioxygen by two-electron transfer and that the presence of H
+ was essential not only to cleave the O-O bond in the peroxomanganese species, but also to transfer the second electron. This catalytic cycle is similar to that of P-450. The current efficiency was 79.1%.CPE of dissolved O
2 was carried out at -1.0V in acetonitrile and superoxide ion was detected by use of an electron spin resonance spectrometer in the frozen electrolyzed solution. Addition of potassium superoxide to acetonitrile containing 1a, 1-methylimidazole and 2 gave 3 (15.6%-26.7%) and 4 (0%-2.7%) in the presence of acetic acid or 5. A similar procedure in the absence of the acid or 5 did not give 3 or 4.When the applied potential was -1.0V, superoxide ion generated by cathodic reduction of dissolved oxygen in the electrolytic solution containing acetic acid was converted into hydrogen peroxide by the reaction with protons. The reaction of manganese (III) porphyrin with hydrogen peroxide produced an oxo-manganese (V) species, which is a strong oxidant and oxidized 2 and 3. This mechanism is similar to the shunt mechanism in the cytochrome P-450 catalytic cycle.
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Shunsaku OHTA, Yasunari HINATA, Masayuki YAMASHITA, Ikuo KAWASAKI, Yok ...
1994 Volume 42 Issue 9 Pages
1730-1735
Published: September 15, 1994
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The reactions of 2-halogenonaphthoquinones (5, 13, 14 and 15) and 2-methyl-1, 4-naphthoquinone (20; vitamin K
3) with primary and secondary amines were examined. 1, 3-Dialkyl-1, 2, 3, 4-tetrahydrobenzo[g]quinazoline-5, 10-diones (9) were obtained in moderate yields by treating 20 with formaldehyde in primary amines. A plausible reaction path-way is also presented.
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Shinji ITOH, Shigeki MATSUO, Itsuo YOSHIZAWA
1994 Volume 42 Issue 9 Pages
1736-1744
Published: September 15, 1994
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To demonstrate the rearrangement reactions of pregnanetriol 20-sulfates in hot acid hydrolysis, 5β-pregnane-3α, 17α, 20α-triol 20-sulfate (8a) and its C-20 isomer 5β-pregnane-3α, 17α, 20β-triol 20-sulfate (12a) were heated in 3M hydrochloric acid. As the sole D-homosteroidal product of each sulfate, 3α-hydroxy-17αβ-methyl-D-homo-5β-androstan-17-one (13a) and 3α-hydroxy-17α-methyl-D-homo-5β-androstan-17a-one (17a) were obtained from 8a and 12a, respectively, accompanied with several kinds of degradation products considered to be monohydroxysteroidal dienes. It became clear that the reaction of 8a proceeds via two steps : ring enlargement of 8a occurred at once to give 3α-hydroxy-17aα-methyl-D-homo-5β-androstan-17-one (14) as the intermediate, followed by isomerization to 13a as the final product.The mechanism of D-homoannulation was elucidated by hydrolysis of [20-
13C]pregnanetriol 20-sulfate (8b, 12b). The D-homosteroid obtained from 8b contained a quantitative amount of the isotope only at C-17a, indicating that the ring-enlargement reaction of the 20α-sulfate proceeds with stereospecific migration of the C
13-C
17 bond. Compound 12b gave the
13C-labelled D-homosteroid enriched solely at C-17, which means that the D-homoannulation of 20β-sulfate occurs by stereospecific migration of the C
16-C
17 bond.The diene products from 8a and 12a were formed from the reaction intermediates 17α, 20β-oxido-5β-pregnan-3α-ol (19) and 17α, 20α-oxido-5β-pregnan-3α-ol (20), respectively.The mechanism of these rearrangement reactions is discussed.
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Hiroyuki FUCHINO, Osamu NOZAWA, Nobutoshi TANAKA
1994 Volume 42 Issue 9 Pages
1745-1749
Published: September 15, 1994
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Double bond migration on the 22(17→28)abeo-lupane skeleton was investigated using 28-p-toluenesulfonyloxy-lupane (4) and its 20(29)-ene derivative (7) as starting materials. In the case of 4, the double bond, formed between C-17 and C-28 after elimination of the p-toluenesulfonyloxy group followed by E-ring expansion, migrated to C-13 and C-18 under acidic conditions. In the case of 7, the double bond, formed after the elimination and the E-ring expansion, migrated in response to migration of the other double bond, 20(29)-ene, under acidic conditions. First, 20(29)-ene migrated to 19-ene (9), and then 17(28)-ene migrated to 13(18)-ene to form a conjugated 13 (18), 19-diene (10). Further migration proceeded to give an equilibrium mixture of 17α-H-11, 13(18)-diene (11), 12, 17-diene (12) and 17β-H-11, 13(18)-diene (13) in a ratio of 3 : 3 : 5.
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Noboru SHOJI, Akemi UMEYAMA, Kazuko YOSHIKAWA, Shigenobu ARIHARA
1994 Volume 42 Issue 9 Pages
1750-1755
Published: September 15, 1994
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From the herb of Anagallis arvensis L., we have isolated five novel oleanane glycosides, anagallosaponins I-V and the artifact, methyl anagallosaponin I, besides anagallosides A, B, C, and desglucoanagallosides A and B. The structures of isolates were identified by the use of 2D-NMR techniques (
1H-
1H correlation spectroscopy (COSY),
1H-detected heteronuclear multiple quantum coherence (HMQC), heteronuclear multiple quantum coherence (HMBC), rotating frame Overhauser enhancement spectroscopy (ROESY), total correlation spectroscopy (TOCSY). The structures of anagallosaponins I and II were characterized as anagallogenin A 3-O-{β-D-glucopyranosyl(1→4)-[β-D-xylopyranosyl (1→2)-]β-D-glucopyranosyl (1→4)-[β-D-glucopyranosyl (1→2)]-α-L-arabinopyranoside} and anagallogenin A 22-acetate 3-O-{β-D-xylopyranosyl (1→2)-O-β-D-glucopyranosyl (1→4)-[β-D-glucopyranosyl (1→2)]-α-L-arabinopyranoside}, respectively. The structures of anagallosaponins III, IV and V were characterized as priverogenin B 22-acetate 3-O-β-D-xylopyranosyl (1→2)-β-D-glucopyranosyl (1→4)-α-L-arabinopyranoside, 3-O-{β-D-xylopyranosyl (1→2)-β-D-glucopyranosyl (1→4)-[β-D-glucopyranosyl (1→2)]-α-L-arabinopyranoside}, 3-O-{β-D-glucopyranosyl (1→4)-[β-D-xylopyranosyl (1→2)]-β-D-glucopyranosyl (1→4)-α-L-arabinopyranoside}, respectively. Methyl anagallosaponin I, the methylacetal of anagallosaponin I might be derived from anagallosaponin I during the isolation procedure.
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Tetsuaki TANAKA, Kaszuo MURAKAMI, Osamu OKUDA, Takeshi KURODA, Tetsuya ...
1994 Volume 42 Issue 9 Pages
1756-1759
Published: September 15, 1994
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Compound 2, corresponding to the B/C/D-ring for aphidicolane-type diterpenes, was synthesized stereoselectively from a perhydroindane derivative (3) which was obtained by rhodium-alumina catalyzed hydrogenation of an indane ester (4) as a key step.
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Masayuki TANNO, Shoko SUEYOSHI, Naoki MIYATA
1994 Volume 42 Issue 9 Pages
1760-1767
Published: September 15, 1994
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Transfer of nitroso groups, so-called transnitrosation, from aromatic N-nitroso compounds such as N-nitrosoureas, N-nitrosamides and N-nitrosamines, to aromatic amines or ureas was observed under non-acidic conditions at room temperature. Sterically hindered 3, 3-dibenzyl-1-(4-tolyl)-1-nitrosourea (1a) rapidly nitrosates indoline, N-alkylanilines or 3-methyl-1-(4-tolyl)urea to give their N-nitroso derivatives. In the case of N, N-dimethylanilines, nitrosative demethylation occurs to give N-methyl-N-nitrosanilines. The transnitrosation is accelerated by electron-releasing groups on the nitroso acceptors, N-alkylanilines. The transnitrosation mechanism is considered to be as follows : N-nitrosourea (1) thermally decomposes to nitric oxide and ureidyl radical followed by formation of an O-nitrosoisourea intermediate (10), which acts as an NO-carrying agent and nitrosates anilines or ureas.
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Takashi ITOH, Hiroshi HASEGAWA, Kazuhiro NAGATA, Yuji MATSUYA, Mamiko ...
1994 Volume 42 Issue 9 Pages
1768-1773
Published: September 15, 1994
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Pyridazines were reacted with allyltributyltin in the presence of chloroformate to give 1-alkoxycarbonyl-6-allyl and 1-alkoxycarbonyl-4-allyldihydropyridazines as major and minor products, respectively. The reaction system was applied to other diazines and pyrimidine and pyrazine were shown to afford diallytetrahydroadducts. Benzodiazines also gave allylation products in good yields. The reaction seems to be applicable to most six-membered azaaromatics.
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Yueh-Hsiung KUO, Wen-Ching CHEN
1994 Volume 42 Issue 9 Pages
1774-1776
Published: September 15, 1994
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Six totarol derivatives were isolated from the extract of the root of Juniperus chinensis LINN. Three known components were identified as totarol, totarolone, and 7-oxototarol. The structures of three new totarol derivatives, 1, 3-dioxototarol, isototarolenone, and 1-oxo-3β-hydroxytotarol, were elucidated on the basis of spectral data and chemical transformation.
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Fumiko ABE, Yujiro MORI, Hikaru OKABE, Tatsuo YAMAUCHI
1994 Volume 42 Issue 9 Pages
1777-1783
Published: September 15, 1994
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Steroidal constituents from the roots and stems of Asclepias fruticosa L. were investigated separately. From the roots, twelve pregnane pentaosides and uzarigenin β-sophoroside were isolated together with three known coroglaucigenin and corotoxigenin glycosides. Pregnane glycosides were composed of ikemagenin or kidjolanin as an aglycone, and D-digitoxose, D-cymarose, D-oleandrose and terminal D-glucose as component sugars. Among the constitutents from the stems, cardenolides show a similar pattern to those from the leaves. 17α-Hydroxycalactin and 17α-hydroxyafroside were newly obtained along with known doubly linked and normally linked glycosides. Two pregnane glycosides and uzarigenin β-sophoroside obtained from the roots were also isolated.
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Masashi OHBA, Takafumi MUKAIHIRA, Tozo FUJII
1994 Volume 42 Issue 9 Pages
1784-1790
Published: September 15, 1994
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Chiral syntheses of 3-methyl-5-(phenylthio)-L-histidine (8a) and 3-methyl-5-(1-naphthalenylthio)-L-histidine (8b), selected as models for the asteroid alkaloid imbricatine (7), have been accomplished through a 10-step route starting from 4(5)-bromoimidazole (9). The key steps involved were methylation of 9, hydroxymethylation of 4-bromo-1-methyl-1H-imidazole (11), replacement of the 4-bromo group by an arylthio group in the aldehyde 14, and introduction of a chiral α-amino acid moiety into the chlorides 17a and 17b by the "bis-lactim ether" method. The synthesis of the 4-(4-methoxybenzyl)thio analogue 17c, carried out in a similar manner, concluded formal syntheses of ovothiols A and C (1 and 3).
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Kazuyoshi OHASHI, Tatsuya TANIKAWA, Yasuaki OKUMURA, Kazuyoshi KAWAZOE ...
1994 Volume 42 Issue 9 Pages
1791-1797
Published: September 15, 1994
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Four new triterpene-glycosides, named gongganosides D (4), E (5), F (6), and G (7), and two new secoiridoid-glucosides, (7R)-7-caffeoyloxysweroside (8) and (7S)-7-caffeoyloxysweroside (9), were isolated from the bark of the Indonesian medicinal plant Bhesa paniculata (Celastraceae). The chemical structures have been elucidated on the bases of their chemical and physicochemical properties.
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Isao KITAGAWA, Partomuan SIMANJUNTAK, Tomokazu WATANO, Hirotaka SHIBUY ...
1994 Volume 42 Issue 9 Pages
1798-1802
Published: September 15, 1994
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Five new cassane-type furanoditerpenes named caesaldekarins a (1), b (2), c, d, and e were isolated from the roots of Caesalpinia major (Fabaceae), an Indonesian medicinal plant. The chemical structures of 1 and 2 have been elucidated on the bases of physicochemical evidence and chemical derivations. The major diterpenoid caesadekarin a (1) was shown to inhibit mitogen responses of mouse spleen cells and interleukin-1 production.
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Takashi YOSHIDA, Yoshiaki AMAKURA, Yan-Ze LIU, Takuo OKUDA
1994 Volume 42 Issue 9 Pages
1803-1807
Published: September 15, 1994
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Three new hydrolyzable tannins, euphormisins M
1, M
2 and M
3, were isolated from Euphorbia hymifusa WILLD., and respectively characterized as 1, 3, 6-tri-O-galloyl-4-O-bravifolincarboxyl-β-D-glucose (19), an oxidative metabolite (23) of geraniin, and 1, 3, 6-tri-O-galloyl-α-D-glucose (18), by spectroscopic and chemical methods. A new ellagic acid glucoside (16) and fifteen known tannins, including geraniin (8) and four dimers [euphorbins A (13), B (14), excoecarianin (15) and eumaculin A (12)], were also isolated.
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Hatsuo MAEDA, Kazushige SHONO, Hidenobu OHMORI
1994 Volume 42 Issue 9 Pages
1808-1812
Published: September 15, 1994
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The effects of Lewis acids (ZnCl
2, AlCl
3, BF
3, and TiCl
4) on the generation of allylzinc species from allyl bromide and unactivated zinc powder in dry tetrahydrofuran (THF) were examined by trapping the organozinc compound with benzaldehyde, that is, Grignard-type allylation of the aldehyde. Among the Lewis acids employed, AlCl
3, was found to be the promoter of choice. The allylzinc species preformed in the presence of a catalytic amount of AlCl
3 effectively allylated carbonyl compounds. Various aromatic and aliphatic aldehydes as well as ketones were converted into homoallylic alcohols in good to excellent yields. Under the reaction conditions employed, ester, hydroxy, acetal, and aromatic nitro and halide groups were tolerated. In the case of α, β-unsaturated carbonyl compounds, selective 1, 2-addition was observed. Substituted allyl bromides such as prenyl, crotyl, cinnamyl, and 2-cyclohexenyl bromides were smoothly converted to the corresponding allylzinc compounds, which reacted with carbonyl compounds to give substituted homoallylic alcohols in excellent yields. The diastereoselectivity in crotylation, cinnamylation, and 2-cyclohexenylation depended upon the structures of both the organic metals and the electrophiles. The origin of the observed selectivity is discussed. The allylation of dimethyl and cyclic acetals accompanied with carbon-oxygen bond cleavege also proceeded in excellent yields provided that two equivalents of AlCl
3 was present.
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Masayuki YOSHIKAWA, Shoko YAMAGUCHI, Hisashi MATSUDA, Yuko KOHDA, Hifu ...
1994 Volume 42 Issue 9 Pages
1813-1816
Published: September 15, 1994
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Following the characterization of the triterpene constituents in Chinese Alismatis Rhizoma, we investigated the chemical structures of orientalols A, B, and C, isolated from the less polar fraction of the crude drug together with two known sesquiterpenes, alismol and alismoxide. On the basis of the chemical and physicochemical evidence, the structures of orientalols A, B, and C have been determined and those of alismol and alismoxide were revised.All five sesquiterpenes were found to show an inhibitory effect on the contraction of isolated bladder smooth muscle induced by carbachol.
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Vincent BAILLEUX, Louis VALLEE, Jean-Pierre NUYTS, Joseph VAMECQ
1994 Volume 42 Issue 9 Pages
1817-1821
Published: September 15, 1994
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The anticonvulsant potential of a series of N-phenylphthalimide derivatives has been screened in subcutaneous pentylenetetrazole seizure (scPTZ) and maximal electroshock seizure (MES) tests. Intraperitoneal 4-amino-N-phenylphthalimides were the most potent agents against MES in mice. Referring to the N-(2, 6-dimethyl-phenyl)phthalimide structure, the order of anticonvulsant activity appears to correspond to the phthalimide ring substitution pattern of 4-amino>4-nitro>4-methyl; H>3-nitro; 3-amino. The 4-amino-N-(2-methylphenyl)-phthalimide displays an anti-MES ED
50 of 47.61μmol/kg with a protective index (PI) of 4.2.Oral administration to rats of the compounds found to be active in mice showed that the 4-amino-N-(2, 6-dimethylphenyl)phthalimide is the most potent anti-MES agent in rats, exhibiting an ED
50 of 25.2μmol/kg and a PI greater than 75. Regarding the nature of the 2 and 6 substituents of the N-phenyl ring, the anticonvulsant efficiencies may be ordered as follows : 2, 6-dimethyl>2-methyl>2-ethyl>2-ethyl-6-methyl>2, 6-diethyl>unsubstituted phenyl ring.N-Phenylphthalimide derivatives seem to have great potential as candidate anticonvulsant drugs.
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Shinji SHIGENAGA, Takashi MANABE, Hiroshi MATSUDA, Takashi FUJII, Masa ...
1994 Volume 42 Issue 9 Pages
1822-1827
Published: September 15, 1994
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A series of N-[4-[4-(1H-indol-3-yl)piperidinoalkyl]-2-thiazolyl]alkanamide derivatives were synthesized and tested for in vivo antianaphylactic activity and in vitro anti slow-reacting substance (SRS) activity. Among the compounds synthesized, N-[4-[4-(1H-indol-3-yl)piperidinomethyl]-2-thiazolyl]propanamide (7) was the best balanced compound (antianaphylactic activity, ED
50=0.92mg/kg p.o.; anti-SRS activity, IC
50=0.89μg/ml). Regarding the biological activities of 7, we ascribe the antianaphylactic activity to its potent antihistaminic activity and the anti SRS activity to the inhibition of 5-lipoxygenase.
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Akito TANAKA, Yukio MOTOYAMA, Hisashi TAKASUGI
1994 Volume 42 Issue 9 Pages
1828-1834
Published: September 15, 1994
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The syntheses and structure-activity relationships of a series of 2-substituted 4, 5-bis(4-methoxyphenyl)pyrimidines, designed on the basis of structural analyses of several cyclooxygenase (CO) inhibitors, and their derivatives as anti-platelet agents based on CO inhibition are described. Among them, 4, 5-bis(4-methoxyphenyl)-2-morpholinopyrimidine (8) and 4, 5-bis(4-methoxyphenyl)-2-(3, 5-dimethylmorpholin-4-yl)pyrimidine (9) showed potent inhibitory activity on malondialdehyde, formed by the CO-catalyzed oxygenation of arachidonic acid (A.A.) in prostanoids, production in vitro (73.4% inhibition at 10
-8M and IC
50=1.4×10
-8M, respectively). Certain compounds were also examined in ex vivo studies. Of these compounds, 4, 5-bis(4-methoxyphenyl)-2-(1-methyl-1, 2, 3, 6-tetrahydropyrid-4-yl)pyrimidine (11a) exhibited potent and long-lasting anti-platelet activity ex vivo, that is, 11a showed 97% inhibition of platelet aggregation induced by A.A. even 24h after oral administration of 3.2mg/kg in guinea pigs, and 60-70% inhibition at 6h after lower doses (1.0mg/kg). The ex vivo activity of 11a is more than three times that of aspirin (aspirin showed 81% inhibitory activity on platelet aggregation induced by A. A. at 6h after oral administration at 10mg/kg in this study). Compound 11a also showed vasodilatory activity (ED
50=5.3×10
-6M, while aspirin has no vasodilatory activity at 6.0×10
-4M).
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Akito TANAKA, Hiroyoshi SAKAI, Takatoshi ISHIKAWA, Yukio MOTOYAMA, His ...
1994 Volume 42 Issue 9 Pages
1835-1840
Published: September 15, 1994
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The syntheses and structure-activity relationships of a series of 3-substituted 5, 6-bis(4-methoxyphenyl)-1, 2, 4-triazines as anti-platelet agents based on cyclooxygenase (CO) inhibition are described. Of these compounds, 1-[5, 6-bis(4-methoxyphenyl)-1, 2, 4-triazin-3-yl]carbonyl-4-methylpiperazine (10) exhibited potent CO inhibition in vitro (IC
50=2.8×10
-7M) with vasodilatory activity (ED
50=4.5×10
-5M). Compound 10 also showed potent ex vivo activities, completely preventing platelet aggregation induced by arachidonic acid and collagen at 6h after oral administration of 3.2 and 1.0mg/kg. The ex vivo potency of 10 is more than three times that of aspirin. Moreover, 10 demonstrated no gastrointestinal side effect in rats even at 100mg/kg in spite of its potent CO inhibition activity, while aspirin, the most widely-used anti-platelet drug, showed gastrointestinal side effects in a dose-dependent manner (32, 100, and 320mg/kg) in our study. These results suggested that 10 is a very attractive candidate for development as an anti-platelet drug since an aspirin-like anti-platelet agent, based on CO inhibition and being free from gastrointestinal side effects, is a major goal of thromboembolic research.
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Naoto UEYAMA, Takashi YANAGISAWA, Tomoyuki KAWAI, Motoharu SONEGAWA, H ...
1994 Volume 42 Issue 9 Pages
1841-1849
Published: September 15, 1994
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Substituted pyridines were synthesized as potential angiotensin II (AII) receptor antagonists. Substitution at the position 2 in the pyridine resulted in potent activity, and the optimal alkyl length was four carbons. The potency further increased with the introduction of a hydroxymethyl group at the position 4. One of the compounds, 2-butyl-6-chloro-4-hydroxymethyl-5-methyl-3-[[2'-(1H-tetrazol-5-yl)biphenyl-4-yl]methyl]pyridine 9h (KT3-579) is a competitive AII antagonist with a pA
2 value of 9.31, and is about 10 times more potent than Du Pont 753. It was found to be an AT
1 specific antagonist with an IC
50 of 3.09nM.
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Masahisa YAMAGUCHI, Takaki KOGA, Kenshi KAMEI, Michitaka AKIMA, Noriak ...
1994 Volume 42 Issue 9 Pages
1850-1853
Published: September 15, 1994
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Synthesis and pharmacological evaluation of several compounds related to 2-[2-(1-imidazolyl)ethyl]-4-(3-pyridyl)-1(2H)-phthalazinones are described. The phenyl moiety of the phthalazinone skeleton was found to play an important role in both thromboxane A
2 synthetase-inhibitory and bronchodilatory activities. Further, the 3-pyridyl group at the 4-position was shown to be necessary for in vivo thromboxane A
2 synthetase-inhibitory activity.
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Toru OKAYAMA, Masaharu NAKANO, Shinjiro ODAKE, Masaki HAGIWARA, Tadano ...
1994 Volume 42 Issue 9 Pages
1854-1858
Published: September 15, 1994
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The tissue-type plasminogen activator (t-PA)-releasing action of synthetic dipeptides containing Gly, Ser or Pro was investigated. Among 10 dipeptides, Boc-L-Ser-L-Pro-OH and H-L-Ser-L-Pro-OH induced t-PA release in vitro, but the others were inactive. Since Boc-L-Ser-L-Pro-OH was more effective than H-L-Ser-L-Pro-OH, 7 related dipeptides with N-acylation were synthesized. Five of them enhanced the release of t-PA; N-stearoyl-L-Ser-L-Pro-OH (FK-5) had the greatest effect. Four compounds were further examined for activity to enhance the release of t-PA in rats. FK-5 produced a two-fold increase in fibrinolytic activity, and N-palmitoyl-L-Ser-L-Pro-OH (FK-4) also markedly enhanced the release of t-PA. Since FK-5 caused severe hemolysis, 7 analogues of FK-5 were synthesized. All of them enhanced the release of t-PA from melanoma (Bowes) cells. In rats, FK-5, N-stearoyl-D-Ser-L-Pro-OH (FK-8) and N-stearoyl-D-Ser-L-Pro-OEt (FK-10) enhanced the fibrinolytic activity two-fold. FK-5 and FK-8 also exhibited strong hemolytic activity, but FK-10 did not induce hemolysis. Therefore, FK-10 was examined in rabbits. After the injection of this compound, the fibrinolytic activity in the euglobulin fraction was markedly enhanced without accompanying hemolysis. Thus, FK-10 potently enhances fibrinolytic activity both in vitro and in vivo.
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Mitsuko MAEDA, Koichi KAWASAKI, Masakatsu TAKAHASHI, Kaoru NAKAO, Hiro ...
1994 Volume 42 Issue 9 Pages
1859-1863
Published: September 15, 1994
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Hybrids of amino-poly(ethylene glycol) (a PEG) and [D-Ala
2, (N-Me)Phe
4]enkephalin analogs, H-Tyr-D-Ala-Gly-(Me)Phe-aPEG, H-Tyr-D-Ala-Gly-(Me)Phe-Leu-aPEG and H-Tyr-D-Ala-Gly-(Me)Phe-D-Leu-aPEG, were prepared by the solution method and their antinociceptive properties were examined in comparison with those of the peptides. H-Tyr-D-Ala-Gly-(Me)Phe-OH and H-Tyr-D-Ala-Gly-(Me)Phe-Leu-OH themselves at intracerebroventricular (i.c.v.) doses of 10-30nmol/animal produced an antinociceptive effect which was less potent than that of i.c.v. morphine, 3μg/animal, and H-Tyr-D-Ala-Gly-(Me)Phe-D-Leu-OH did not have any marked effect. However, the antinociceptive effects of H-Tyr-D-Ala-Gly-(Me)Phe-Leu-OH and H-Tyr-D-Ale-Gly-(Me)Phe-D-Leu-OH were remarkably potentiated by hybrid formation with aPEG to levels higher than that of 3μg/mouse of morphine, and the effect lasted at least 120min. In contrast, the effect of H-Tyr-D-Ala-Gly-(Me)Phe-OH was rather diminished by hybrid formation. In view of the low toxicity and weak immunogeic properties of aPEG, the hybrids could be useful in therapy of patients for relieving chronic and severe pain.
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Tadashige CHIBA, Toshifumi AKIZAWA, Motomi MATSUKAWA, Hidemitsu PAN-HO ...
1994 Volume 42 Issue 9 Pages
1864-1869
Published: September 15, 1994
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A series of joro spider toxins, novel polyamines sharing a common moiety of 2, 4-dihydroxyphenylacetyl cadaverine, have been identified using various bioassays, such as inhibition of a glutamatergic transmission and insecticidal activity. In this paper, we tried to chemically find still unknown polyamine toxins in the venom of a joro spider, N. clavata, by several analytical methods based on the characteristics of the common moiety. An aqueous extract from 3000 venoms was separated by preparative high performance liquid chromatography (HPLC). The polyamine toxins were detected by monitoring the fluorescence produced in an on-line reaction of o-phthalaldehyde with amino groups and UV absorption of the phenol group. Two compounds in minute quantity were purified and analyzed by gas-liquid chromatography (GC) and HPLC, which we specifically developed for the simultaneous determination of amino acids and polyamines of the toxins. Judging from the constituents of the hydrolysate by GC and HPLC and the molecular weights determined by fast atom bombardment mass spectrometry, the two compounds were estimated to be N-(2, 4-dihydroxyphenylacetyl-L-asparaginyl)-N'-(3-aminopropyl-β-alanyl) cadaverine and N-(4-hydroxyphenylacetyl-L-asparaginyl-N'-(3-aminopropyl-β-alanyl) cadaverine. These compounds were small in content and molecular weight compared with hitherto known toxins. Both were presumed to be biochemically primitive toxins and were named spidamine and joramine, respectively.
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Hatsuo MAEDA, Yuji YAMAUCHI, Masayuki HOSOE, Tong-Xing LI, Eiichi YAMA ...
1994 Volume 42 Issue 9 Pages
1870-1873
Published: September 15, 1994
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The modification of a glassy carbon (GC) electrode with an alkanol by electrochemical oxidation was examined. When a GC electrode was oxidized by multiple potential sweep between 0 and 2.0V vs. Ag wire in 1-octanol containing H
2SO
4 (1M), the electrode was modified with octanol, probably through an ether linkage, as judged from the voltammetric behavior of Fe(CN)
3-6 and catechol at the treated electrode, which closely resembled that at a long-chain alkanethiol-modified gold electrode. In the modification, the potential range and the sweep rate affected the extent of linking of the alcohol to the surface, and a potential sweep at 10mV/s from 0 to 2.0V gave a GC electrode tightly covered with the alcohol. The membrance thus formed on the GC electrode was stable not only to applied potential bias over the range from -0.5 to 1.5V vs. SCE (saturated calomel electrode) in 0.1M aqueous NaCl solution but also to sonication in H
2O and MeOH. n-Alkanols of various chain lengths were also used to modify a GC electrode. The depression of the electrode process of Fe(CN)
3-6 at the modified electrodes was enhanced as the carbon number in the modifiers increased.
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Junei KINJO, Fumiko KISHIDA, Kazutaka WATANABE, Fumio HASHIMOTO, Toshi ...
1994 Volume 42 Issue 9 Pages
1874-1878
Published: September 15, 1994
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In a continuing study on the ingredients of Lupinus genus, we examined the oligoglycoside constituents of the Russell lupine (L. polyphyllus×L. arboreus hybrid). Five new oleanene glycosides, called Lupinosides PA
1-5 (1-5), together with three known ones were isolated. Their structures of 1-5 were determined to be 3-O-α-L-rhamno-pyranosyl-(1→2)-β-D-glactopyranosyl-(1→2)-β-D-glucuronopyranosyl soyasapogenol A 21-O-β-D-xylopyranoside (1), 3-O-β-D-galactopyranosyl-(1→2)-β-D-glucuronopyranosyl soyasapogenol A 21-O-β-D-xylopyranoside (2), 3-O-α-L-rhamnopyranosyl-(1→2)-β-D-galactopyranosyl-(1→2)-β-D-glucuronopyranosyl kudzusapogenol A 21-O-β-D-xylopyranoside (3), 3-O-α-L-rhamnopyranosyl-(1→2)-β-D-galactopyranosyl-(1→2)-β-D-glucuronopyranosyl soyasapogenol B 22-O-α-L-rhamnopyranoside (4), and 3-O-α-L-rhamnopyranosyl-(1→2)-β-D-galactopyranosyl-(1→2)-β-D-glucuronopyranosyl soyasapogenol B 22-O-β-D-glucopyranosyl-(1→4)-α-L-rhamnopyranoside (5), respectively.
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Hideki SAITOH, Toshio MIYASE, Akira UENO
1994 Volume 42 Issue 9 Pages
1879-1885
Published: September 15, 1994
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Ten new acylated oligosaccharides, called reinioses A-J, and seven known oligosaccharides were isolated from the roots of Polygala reinii FR. et SAV. and their structures were elucidated by spectroscopic and chemical means. These oligosaccharides were found to be di-, tri-, tetra- and pentasaccharides having two or more acyl residues.
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Naoko OHARA, Masashi TOMODA, Noriko SHIMIZU, Ryoko GONDA
1994 Volume 42 Issue 9 Pages
1886-1889
Published: September 15, 1994
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An acidic polysaccharide, called cnidirhan SIIB, was isolated from the rhizome of Cnidium officinale MAKINO. It was homogeneous on electrophoresis and gel chromatography, and its molecular mass was estimated to be 7.9×10
4. It was composed of L-arabinose, D-galactose and D-galacturonic acid in the molar ratio of 9 : 11 : 3, in addition to a few O-acetyl groups. Reduction of carboxyl groups, methylation analysis, nuclear magnetic resonance and controlled Smith degradation studies indicated that its structural features are composed primarily of α-L-arabino-β-3, 6- and 3, 4-branched D-galactan type units. The polysaccharide showed very pronounced reticuloendothelial system-potentiating activity in a carbon clearance test and marked anti-complementary activity.
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Yasuko MORIMOTO, Yoshikazu TAKEUCHI
1994 Volume 42 Issue 9 Pages
1890-1895
Published: September 15, 1994
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The protective effect of glycine against the perturbing action of chlorpromazine (CPZ) on liposome membranes was investigated by an electron spin resonance (ESR) tecnique. Analysis using a 5-doxyl stearic acid (DS) spin probe indicated that the hydrophobic region near the surface of the liposomes containing glycine was restricted in motion by the addition of CPZ. This result suggested that the spaces between hydrocarbons in this portion would be narrowed by the penetrance of cationized CPZ molecules into the polar-hydrocarbon interface of the liposomes, in which the surface region may be tightly packed by glycine. The presence of glycine caused no difference in the disordering action of CPZ in the 12-DS reporting portion, suggesting that glycine could not influence the depth of the penetrance of cationized CPZ into the hydrocarbon phase near the surface of liposomes. The perturbing action of CPZ on the 16-DS-labeled liposomes was weakened by the presence of glycine, suggesting the reduced penetrance of undissociated CPZ molecules into the center of the bilayers (lipid core). Thus, glycine presumably prevented CPZ molecules incorporated into the liposome surface from transferring into the lipid core by its packing effect. It was shown that glycine could reduce the liposome lytic action of CPZ, without decreasing its surface activating action. This observed anti-lytic effect could be explained as a result of the above-described inhibition of the penetrance of CPZ into the lipid core.
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Kaoru KAMIYA, Yasukichi YANAGIHARA, Tomokazu TAKAI, Masayuki KUZUYA
1994 Volume 42 Issue 9 Pages
1896-1901
Published: September 15, 1994
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To evaluate the effect of plasma treatment on protein adsorption onto a polymer surface, we carried out Ar plasma irradiation on polymethylmethacrylate (PMMA) plate and examined the adsorption behavior of protein after immersion of plasma treated PMMA plate in the artificial tear solution containing lysozyme, albumin and γ-globulin. It was found that the total adsorption of protein in the artificial tear solution to PMMA is suppressed by the Ar plasma treatment. But the adsorption of each component protein differs according to the surface condition of polymers and obviously corresponds to the change with time in the surface wettability. It is concluded that introduction of a hydropholic group into the PMMA surface by plasma treatment and coming off of it are associated with the adsorption behavior of proteins. Since the adsorption of protein to the plasma-treated PMMA surface changes over time, care should be exercised in determining it, when an attempt is made to clarify the effect of plasma irradiation on the adsorption to the plasma-irradiated polymer surface.
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Manabu MATSUMURA, Hiroaki NAKAGAMI, Tadanao YAMAO, Kozo TAKAYAMA, Tsun ...
1994 Volume 42 Issue 9 Pages
1902-1908
Published: September 15, 1994
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A computer optimization technique based on response surface methodology was applied to the formulation optimization of a controlled-release tablet made of micronized low-substituted hydroxypropylcellulose (L-HPC) and methylcellulose (MC) as matrix carriers. Theophylline was selected as the model drug, and was directly compressed with these carriers. Since the tablet showed slow disintegration from the outer layer, release was estimated to involve a coupling of diffusion and erosion release mechanisms. The percentage of drug released at time i (D
i) and percent disintegration of the matrix not including the drug at 5h (Dis
5) were examined. D
i and Dis
5 decreased with an increase in the amount of micronized L-HPC (X
1) and with a decrease in the amount of MC (X
2) in the tablet. In contrast, they were little affected by compression pressure (X
3). These response variables-D
i and Dis
5-were predicted well by a multiple regression equation involving the combination of X
1, X
2 and X
3. In the optimization study, formulation of the controlled-release tablet was examined to obtain zero-order release over 10h. The predicted release rate obtained from the optimum formula agreed well with experimental values. The result suggests that the technique is useful for the formulation optimization of this matrix system, and that this system has the potential to control the release rate, including zero-order release profile.
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Anshu DANDIA, Varinder SEHGAL, Pahup SINGH
1994 Volume 42 Issue 9 Pages
1909-1911
Published: September 15, 1994
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A facile synthesis of novel spiroindole derivatives, spiro[3H-indole-3, 4'-2', 3', 4', 5', 6', 7'-hexahydro-1H-pyrano-[2, 3-b : 6, 5-b']dipyrrole[-2(1H)-ones (IV), together with 2, 3-dihydro-3-(2, 3, 4, 5-tetrahydro-2-oxo-1H-pyrrole-3-ylidene-1H-indol-2-ones (II), was achieved by dry heating of substituted indole-2, 3-diones with 2-pyrrolidinone or N-methyl-2-pyrrolidinone.
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Kazutada KITANO, Yoshio MATSUBARA, Masakuni YOSHIHARA, Toshihisa MAESH ...
1994 Volume 42 Issue 9 Pages
1912-1913
Published: September 15, 1994
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Reaction of N'-phenylthioformohydrazide with ketones in the presence of trimethylsilyl chloride proceeded easily to afford the corresponding 2, 2-disubstituted 2, 3-dihydro-3-phenyl-1, 3, 4-thiadiazoles in good yields.
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Marie-Helene MUNOS, Joelle MAYRARGUE, Alain FOURNET, Jean-Charles GANT ...
1994 Volume 42 Issue 9 Pages
1914-1916
Published: September 15, 1994
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Synthesis of an antileishmanial alkaloid and related compounds by using various epoxide-forming reactions is described.
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Hiroshi SUSAKI
1994 Volume 42 Issue 9 Pages
1917-1918
Published: September 15, 1994
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1-Hydroxy sugars (1a-4a) were directly coupled with free alcohols (5b-d) to give the corresponding glycosides by using trimethylsilyl chloride and zinc triflate as promoters.
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Masanori SAKAMOTO, Yasumichi FUKUDA, Taeko KAMIYAMA, Tomomi KAWASAKI
1994 Volume 42 Issue 9 Pages
1919-1921
Published: September 15, 1994
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Reaction of diethyl phosphorocyanidate (DEPC) with dimethyl malonate (1a) and ethyl cyanoacetate (1b) in the presence of zinc chloride and triethylamine resulted in selective addition of 1a, b to the cyano group of DEPC to give α, β-unsaturated α-aminophosphonates (2a, b). In contrast, similar treatment of enolizable methyl acetoacetate (1c) and acetylacetone (1d) with DEPC gave the corresponding enolphosphates (4c, d) as a result of nucleophilic displacement on the phosphorus atom of DEPC. Conversion of the resulting α-aminophosphonate (2a) to uracil-6-phosphonates (6a, b) was achieved by treatment with phenyl isocyanate (5a) and isothiocyanate (5b), respectively.
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Chyurng Wern CHANG, Ling Ling YANG, Kun Ying YEN, Tsutomu HATANO, Taka ...
1994 Volume 42 Issue 9 Pages
1922-1923
Published: September 15, 1994
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A new acylated γ-pyrone glucoside was isolated from the leaf extract of Gordonia axillaris (Theaceae), and was characterized as 3-O-(6'-O-galloyl)-β-D-glucopyranosylmaltol (7) based on two-dimensional NMR experiments and other spectroscopic analyses. 5-O-(6'-O-Galloyl)-β-D-glucopyranosylgentisic acid (6), and two dimeric hydrolyzable tannins [camelliin B (4) and schimawalin B (5)] were also isolated.
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Kazuyoshi OHASHI, Hisashi WATANABE, Yasuaki OKUMURA, Tahan UJI, Isao K ...
1994 Volume 42 Issue 9 Pages
1924-1926
Published: September 15, 1994
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From the bark of Aegle marmelos CORREA (Rutaceae), an Indonesian medicinal plant, two new lignan-glucosides, (-)-lyoniresinol 2α-O-β-glucopyranoside (3) and (-)-4-epi-lyoniresinol 3α-O-β-D-glucopyranoside (4), have been isolated together with two known lignan-glucosides, (+)-lyoniresinol 3α-O-β-D-glucopyranoside (1) and (-)- lyoniresinol 3α-O-β-D-glucopyranoside (2).
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Taisuke ITAYA, Shigeyuki SHIMIZU, Satoshi NAKAGAWA, Masatoshi MORISUE
1994 Volume 42 Issue 9 Pages
1927-1930
Published: September 15, 1994
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Vinylglycine (2) has been shown to undergo racemization under acidic conditions. Optically pure 2 was obtained from 2·HCl by enzymatic hydrolysis through N-acetylvinylglycine (5), followed by recrystallization. (S)-N-(Methoxycarbonyl)vinylglycine (6) was configurationally so unstable under acidic conditions that 6 could not be obtained from 2 in an optically pure form. On the other hand, configurationally stable (S)-N-(9-phenylfluoren-9-yl)vinylglycine methyl ester (9) was synthesized from (S)-homoserine; 9 was hydrolyzed with sodium hydroxide to afford the carboxylic acid 10 of more than 99% ee.
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Tokujiro KITAGAWA, Junko ITO, Chinatsu TSUTSUI
1994 Volume 42 Issue 9 Pages
1931-1934
Published: September 15, 1994
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The reaction of imidazole (15) with formyl chloride (14), generated in situ by the action of oxalyl chloride (10) on formic acid (3), afforded N-formylimidazole (7), which is a convenient formylating reagent. This procedure was used to prepare N-formyl derivatives (2) of aliphatic, aromatic and heteroaromatic amines (1) under mild conditions.
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Reiko YODA, Yoshikazu MATSUSHIMA
1994 Volume 42 Issue 9 Pages
1935-1937
Published: September 15, 1994
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3-Aminooxypropyliminodiacetic acid, 4-aminooxybutyliminodiacetic acid and 5-aminooxypentyliminodiacetic acid and their oxime derivatives with several carbonyl compounds were synthesized and characterized. The ω-aminooxyalkyliminodiacetic acids act as bifunctional chelating agents for metal-labeling of a carbonyl group.
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Muneharu MIYAKE, Yasuo FUJIMOTO
1994 Volume 42 Issue 9 Pages
1938-1939
Published: September 15, 1994
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The effects of a novel water-soluble cyclophane (TGCP 44, 1) on the hydrolysis reactions of aromatic esters have been studied. TGCP 44(1) was found to inhibit the hydrolysis of three aromatic esters, p-nitrophenyl chloroacetate (2), glycine p-nitrophenyl ester hydrobromide (3) and 1-nitro-2-naphthyl chloroacetate (4). The hydrolysis rates of the aromatic esters were retarded by 3.8-7.65 fold relative to the spontaneous rates.
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Akiko KUSANO, Makio SHIBANO, Satoshi KITAGAWA, Genjiro KUSANO, Shigeo ...
1994 Volume 42 Issue 9 Pages
1940-1943
Published: September 15, 1994
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Two new diglycosides (I, II) were isolated from the aerial parts of Cimicifuga smplex (Ranunculaceae), and their structures were determined to be 25-O-acetylcimigenol 3-O-β-D-glucopyranosyl-(1→3)-β-D-xylopyranoside (I) and 23-O-acetylshengmanol 3-O-β-D-glucopyranosyl-(1→3)-β-D-xylopyranoside(II). Two known xylosides (Ia, IIa) were also isolated and identified as 25-O-acetylcimigenol 3-O-β-D-xylopyranoside (Ia) and 23-O-acetylshengmanol 3-O-β-D-xylopyranoside (IIa). Cellulase A [Amano] 3 hydrolyzed I and II to afford Ia and IIa respectively, while Cellulase T [Amano] 4 hydrolyzed I and II to afford 25-O-acetylcimigenol (Ib) and 23-O-acetylshengmanol (IIb) as the aglycones, respectively.
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Yasunori YAOITA, Masao KIKUCHI
1994 Volume 42 Issue 9 Pages
1944-1947
Published: September 15, 1994
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Six new eremophilenolides, 3β-hydroxyeremophil-7(11)-en-12, 8β-olide (1), 3β-hydroxy-6β-methoxyeremophil-7(11)-en-12, 8β-olide (2), 3β-hydroxy-6β, 8α-dimethoxyeremophil-7(11)-en-12, 8β-olide (3), the mixture of 3β, 8α-dihydroxy-6β-tigloyloxyeremophil-7(11)-en-12, 8β-olide (4) and 3β, 8β-dihydroxy-6β-tigloyloxyeremophil-7(11)-en-12, 8α-olide (5), and 6β-angeloyloxy-8β-hydroxy-3-oxoeremophil-7(11)-en-12, 8α-olide (6), were isolated from the dried rhizomes of Petasites japonicus MAXIM. (Compositae). The structures of these compounds were elucidated on the basis of spectroscopic evidence.
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Etsuo YONEMOCHI, Kaoru ODA, Seiji SAEKI, Toshio OGUCHI, Yoshinobu NAKA ...
1994 Volume 42 Issue 9 Pages
1948-1950
Published: September 15, 1994
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The crystallinity and disorder parameters of intact and ground ursodeoxycholic acid were determined by the X-ray diffraction method based on Ruland's theor. An increase in grinding time caused a decrease in crystallinity, while the disorder parameters were independent of the grinding time. Dissolution rates were measured for ursodeoxycholic acid with different crystallinities, and the recrystallization behavior of the amorphous samples was investigated during storage in a vapor of water, n-hexane, n-octane and n-decane. The amorphous ursodeoxycholic acid showed enhanced dissolution in ethanol, and was stable only under dry conditions.
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Toshiaki MORIMOTO, Noriya NAKAJIMA, Kazuo ACHIWA
1994 Volume 42 Issue 9 Pages
1951-1953
Published: September 15, 1994
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A neutral iridium(I) complex of (4R, 5R)-MOD-DIOP (1b) was found to be an efficient catalyst for the asymmetric hydrogenation of imines, N-(α-methylbenzylidene)benzylamine (4) and 2, 3, 3-trimethylindolenine (6), in the presence of tetrabutylammonium iodide. A high enantioselectivity with up to 81.4% ee was achieved.
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Hirofumi TAKEUCHI, Hiromitsu YAMAMOTO, Toshiyuki NIWA, Tomoaki HINO, Y ...
1994 Volume 42 Issue 9 Pages
1954-1956
Published: September 15, 1994
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Multilamellar liposomes consisting of dipalmitoyl phosphatidylcholine (DPPC) and dicetyl phosphate (DCP) in a molar ratio of 8 : 2 (DPPC : DCP=8 : 2) were coated with three different types of polymers : chitosan, polyvinyl alcohol having a long alkyl chain, and poly(acrylic acid) bearing cholesterols. The existence of polymer layers on the liposome surface was confirmed by measuring the zeta potential of the liposomal particles. The mucoadhesive function of the polymer-coated liposomes was evaluated in vitro using rat intestine. A particle counting method using the Coulter counter was adopted to evaluate the adhesive % of liposomes. Chitosan coated liposomes showed the highest adhesive % among the polymer-coated liposomes tested. No adhesive % was observed for the non-coated liposomes. The adhesion of chitosan-coated liposomes to the intestine wall was confirmed by fluorescence microscopy using pyren loaded liposomes.
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