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Volume 46, Issue 1
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Shinichi UESATO, Yoshihiro KURODA, Masahiro KATO, Yasuhiro FUJIWARA, Y ...1998 Volume 46 Issue 1 Pages 1-5
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe stereostructures of anticoccidial agents, febrifugine and halofuginone, as well as the corresponding cis-isomers, in organic solvents were determined through NMR analyses, isomerization reactions and AM1 molecular orbital calculations.View full abstractDownload PDF (751K) -
Akira MIYASHITA, Yumiko SUZUKI, Yoko OKUMURA, Ken-ichi IWAMOTO, Takeo ...1998 Volume 46 Issue 1 Pages 6-11
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWhen α-benzylbenzoin (3a, α-benzyl-α-hydroxybenzyl phenyl ketone) was treated with potassium cyanide (1) in N, N-dimethylformamide at 80°C for 1 h, the carbon-carbon bond was cleaved, resulting in the formation of deoxybenzoin (4a, benzyl phenyl ketone) and benzaldehyde (2a). This carbon-carbon bond cleavage proceeds through a retro-benzoin condensation mechanism. This mothod of synthesizing ketones was applied to several α-substituted benzoins (3), and the corresponding ketones (4) were formed in good yields. Further, we found that the cyanide ion-donating ability of tetrabutylammonium cyanide (6, Bu4NCN) is more effective than that of potassium cyanide (1, KCN). As expected from the chemical analogy between cyanide ion and azolium ylide, serveral azolium salts (7) can also be employed in the retro-benzoin condensation as catalysts.The benzoin derivatives 3 were synthesized in the following three ways; reaction of alkyl halide (9) with benzoin (5), Michael addition of benzoin (5) with acceptors (10), and Grignard reaction of benzils (8). Alkylation of the benzoins without isolation, followed by carbon-carbon bond cleavage, readily afforded the corresponding ketones (4).View full abstractDownload PDF (915K) -
Hitoshi ISHIDA, Hidetoshi NAKAYASU, Hidekazu MIYAMOTO, Haruo NUKAYA, K ...1998 Volume 46 Issue 1 Pages 12-16
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSNew sodium bile alcohol sulfates (1a and 1b), two sodium cyprinol sulfates (2a and 2b), and the sodium salt of a new bile acid conjugated with taurine (3) were isolated from the bile of sunfish, Mola mola L., by chromatography on silica gel and octadecylsilane (ODS), together with sodium taurocholate (4). On hydrolysis with pyridine and dioxane, the new sulfates 1a and 1b both afforded a new bile alcohol (5), whose structure was determined to be 5β-cholestane-3α, 7, α11α, 26, 27-pentol, based on the physico-chemical data. On the basis of this result and their physiochemical data, the new sulfates were established as (25S)- and (25R)-(+)-3α, 7α, 11α, 26-tetrahydroxy-5β-cholestan-27-yl sodium sulfate. Based on the physicochemical data and chemical transformations, the sodium cyprinol sulfates were identified as (25S)- and (25R)-(+)-3α, 7α, 12α, 26-tetrahydroxy-5β-cholestan-27-yl sodium sulfate and compound 3 as sodium 2-[[3α, 7α, 11α-trihydroxy-24-oxo-5β-cholan-24-yl]amino]ethanesulfonate.View full abstractDownload PDF (861K) -
Tamaki HORIKAWA, Yoshihiko NORIMINE, Masakazu TANAKA, Kiyoshi SAKAI, H ...1998 Volume 46 Issue 1 Pages 17-21
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSOptically active 5-cyclooctene-1, 2-diol derivatives prepared by an enzymatic procedure have been converted into bicyclo[3.3.0]octane derivatives by transannular reaction with complete inversion of the stereogenic center linked to the leaving group. Formal synthesis of (+)-iridomyrmecin has been achieved starting from (S, S)-5-cyclooctene-1, 2-diol by using this process.View full abstractDownload PDF (782K) -
Mitsuya HONGU, Takashi TANAKA, Nobuyuki FUNAMI, Kunio SAITO, Kenji ARA ...1998 Volume 46 Issue 1 Pages 22-33
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA novel series of 4'-dehydroxyphlorizin derivatives was synthesized and the effects of these compounds on urinary glucose excretion were evaluated in rats. There was a strict structural requirement for activity. Introduction of a small substituent or a flat ring at the 3- and/or the 4-position on the A ring was permissible, but any change at the bridge part between the A and B rings or in the sugar moiety resulted in complete loss of activity. The 6'-OH group on the B ring was also necessary, and even small structural modifications of the 6'-OH group reduced the activity considerably. Among the compounds synthesizez, the 5-benzofuryl derivative 25 was the most potent and was selected as a new lead for further structure-activity relationship investigations.View full abstractDownload PDF (1562K) -
Judith RAZAFIMBELO, Genevieve BAUDOUIN, Francois TILLEQUIN, Pierre REN ...1998 Volume 46 Issue 1 Pages 34-41
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSCondensation of 5-amino, 6-amino, 7-amino and 8-amino-2, 2-dimethyl-2H-chromenes with either 6-bromo-veratraldehyde or 6-chloropiperonal afforded the corresponding Schiff bases, which were subsequently reduced to the corresponding benzylchromenylamines 30-33 and 36-39. Lithium diisopropylamide-mediated cyclization of those amines, followed by spontaneous air oxidation, afforded pyranophenanthridines 3-14. The cytotoxicity of compounds 3-14 was evaluated against L1210 and HT29 cell lines. 9, 9-Dimethyl-9H-pyrano[3, 2-b]phenanthridines appear to be the most promising compounds of the series, since both the dimethoxy derivative 11 and the methylenedioxy derivative 12 exhibit significant cytotoxic activity. Compound 12 was the most active and induced a massive accumulation of cells in G2+M phases, suggesting that the cytotoxicity is due to a perturbation of the integrity or function of DNA.View full abstractDownload PDF (1186K) -
Takuji KAKIGAMI, Toshinao USUI, Katsura TSUKAMOTO, Tadashi KATAOKA1998 Volume 46 Issue 1 Pages 42-52
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe title compounds (6-9) were prepared and evaluated for serotonin 5-HT4 agonistic activity in in vitro tests. Introducing a propyl or allyl group at the 3-position of benzamide caused only a slight enhancement of agonistic activity. Construction of the benzo[b]furan skeleton and 2, 3-dihydrobenzo[b]furan skeleton caused a significant enhancement of the activity. 4-Amino-N-[2-(1-azabicyclo[3.3.0]octan-5-yl)ethyl]-5-chloro-2-methylbenzo[b]furan-7-carboxamide (7b) hemifumarate was as potent as cisapride. 4-Amino-N-[2-(1-azabicyclo[3.3.0]octan-5-yl)ethyl]-5-chloro-2, 3-dihydro-2-methylbenzo[b]furan-7-carboxamide (8a) hemifumarate, 4-amino-N-[2-(1-azabicyclo-[3.3.0]octan-5-yl)ethyl]-5-chloro-2, 3-dihydro-2-ethylbenzo[b]furan-7-carboxamide (8c) hemifumarate, and 4-amino-N-[2-(1-azabicyclo[3.3.0]octan-5-yl)ethyl]-5-chloro-2, 3-dihydro-2, 3-dimethylbenzo[b]furan-7-carboxamide (8d) hemifumarate were potent than cisapride. Furthermore, 8a hemifumarate was free from dopamine D1, D2, serotonin 5-HT1, 5-HT2 and muscarine M1, M2 receptor binding activity in the in vitro tests. On the other hand, construction of the indole skeleton caused a remarkable decrease in activity.View full abstractDownload PDF (1468K) -
Toshihiro WATANABE, Akio KAKEFUDA, Akihiro TANAKA, Kenji TAKIZAWA, Sei ...1998 Volume 46 Issue 1 Pages 53-68
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA series of phenylacetyl derivatives containing the 5, 10-dihydro-11H-dibenzo[b, e][1, 4]diazepin-11-one or 5, 11-dihydro-6H-pyrido[2, 3-b][1, 4]benzodiazepin-6-one skeleton was prepared and evaluated for their binding affinities to muscarinic receptors in vitro and for antagonism of bradycardia, salivation and tremor in vivo. Among them, compounds 56 and 66 had high affinity for M2 muscarinic receptors in the heart (pKi=8.7 and 8.9, respectively) with low affinity for M3 muscarinic receptors in the submandibular gland. A structure-activity relationship (SAR) study suggested that the high M2 selectivity over the M3 muscarinic receptors of 56 may be attributed to the direction of the carboxamide carbonyl group. In in vivo studies, 56 and 66 antagonized oxotremorine-induced bradycardina in rats on both intravenous and oral administration, and their heart rate increasing effect in dogs with nocturnal bradycardia was about 3-fold greater than that of AF-DX 116. Furthermore, they had almost no influence on oxotremorine-induced tremor in mice, presenting no evidence of central transfer.View full abstractDownload PDF (2222K) -
Toshio OKAZAKI, Akira SUGA, Toshihiro WATANABE, Kazumi KIKUCHI, Hiroyu ...1998 Volume 46 Issue 1 Pages 69-78
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAlkyl-substituted pyrazolo[1, 5-b][1, 2, 4]triazole derivatives were synthesized and evaluated for activity as angiotensin II receptor antagonists. Molecules with the (methylbiphenyly)tetrazole moiety at N-5 were the preferred compounds. Ethyl substitutions a both C-2 and C-7 resulted in the optimal compound, 2, 7-diethyl-5-[[2'-(1H-tetrazol-5-yl)biphenyl-4-yl]methyl]-5H-pyrazolo[1, 5-b][1, 2, 4]triazole (5n), with a pA2 value of 8.74 in rabbit aorta. In the in vivo tests, 5n inhibited the angiotensin II-induced pressor response in rats after oral administration. This compound also produced a dose-dependent decrease in blood pressure when administered orally to conscious furosemide-treated dogs, having a longer duration of action as compared to DuP 753. These data suggest that 5n may be a useful agent for the treatment of angiotensin II-dependent disease, such as hypertension.View full abstractDownload PDF (1249K) -
Anne GONZALEZ DE PEREDO, Stephane LEONCE, Claude MONNERET, Daniel DAUZ ...1998 Volume 46 Issue 1 Pages 79-83
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA series of novel flavonoids comprising structural elements present in the antineoplastic agents podophyllotoxin and etoposide was synthesized. These oxygen-containing analogues of antiproliferative quinolones exhibited moderate cytotoxicity towards L1210 and HT-29 cell lines.View full abstractDownload PDF (809K) -
Toshimi SEKI, Arihiro KANADA, Tomio NAKAO, Masahumi SHIRAIWA, Hajime A ...1998 Volume 46 Issue 1 Pages 84-96
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSynthesis of the four optical isomers of TZC-5665 (1), a candidate for the treatment of congestive heart failure, was achieved by the reaction of chiral diaminopyridazinone (2) with chiral glycidyl ether (3). The hypotensive and β-blocking activities of 1 and its optical isomers were examined when given intravenously into anesthetized rats. Furthermore these compounds were evaluated for inhibitory activity on cAMP phosphodiesterase III. Among the four optical isomers. RA, SB-one (1c) possessed the essential activities of TZC-5665 (1).View full abstractDownload PDF (1909K) -
Hidenao TOYODA, Yoshikuni DEMACHI, Shizuyo KOMORIYA, Nobuyoshi FURUYA, ...1998 Volume 46 Issue 1 Pages 97-101
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSKeratan sulfate was isolated from normal human urine was characterized by sugar compositional analysis and 1H-NMR spectroscopy. It was found that KS from human urine is classified as skeletal type (KS-II type chain) with an O-glycosidic linkage between galatosamine and serine (or theronine). 1H-NMR studies revealed that urinary KS is not a proteoglycan but a polysaccharide (molecular weight is about 5kDa). The quantitation of human urinary KS by HPLC showed that urinary KS is excreted at constant levels (0.07±0.015 μg/mg creatinine).View full abstractDownload PDF (694K) -
Osamu SHIROTA, Hiroshi MORITA, Koichi TAKEYA, Hideji ITOKAWA1998 Volume 46 Issue 1 Pages 102-106
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSNew geometric and stereoisomeric triterpene dimers, 7, 8-dihydroisoxuxuarine Eα (2), xuxuarines Fβ (3), Gα (4) and Gβ (5), along with a known compound, scutidin αA (1), were isolated from the South American medicinal plant "xuxua" (Maytenus chuchuhuasca RAYMOND-HAMET et COLAS). Their structures were determined on the basis of spectroscopic evidence including CD spectral studies.View full abstractDownload PDF (782K) -
Yasuhiro TEZUKA, Rena KASIMU, Jian Xin LI, Purusotam BASNET, Ken TANAK ...1998 Volume 46 Issue 1 Pages 107-112
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSalvia deserta SCHANG. (Lamiaceae) is a plant grown in Xinjiang province in China, and its dried roots are called Xinjiang-Danshen. This plant has not been used as a medicine or a food, but recently it was reported that Xinjiang-Danshen is mixed in Dashen (roots of S. miltiorhiza BUNGE), a well-known Chinese crude drug, at Xinjiang province when latter was in short supply. We examined the constitutents of the roots of S. deserta (Xinjiang-Danshen) and identified a new caffeic acid trimer [salvianolic acid K (1)], along with two known caffeic acid dimers [salviaflaside (2), rosmarinic acid (3)], a known caffeic acid tetramer [lithospermic acid B (4)], seven known abietane-type diterpenes [6, 7-dehydroroyleanone (5), royleanone (6), taxodione (7), ferruginol (8), 7-O-methylhorminone (9), 7-O-acetylhorminone (10), horminone (11)], and a known steroid [daucosterol (12)].Five of the diterpenes (5, 6, 9-11) were "royleanones" and the main caffeic acid derivative was the trimer 1. These differed from the constituents of roots of S. miltiorhiza, which contains "tanshinones" as diterpenes and magnesium lithospermate B as the main caffeic acid derivative. Thus, the mixing of Xinjiang-Danshen with Danshen is not appropriate and two should be considered different drugs.View full abstractDownload PDF (870K) -
Masayuki YOSHIKAWA, Hiromi SHIMADA, Norihisa NISHIDA, Yuhao LI, Iwao T ...1998 Volume 46 Issue 1 Pages 113-119
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe methanolic extract and ethyl acetate-soluble portion from a Brazilian natural medicine, the leaves of Myrcia multiflora DC., which has been used as a specific medicine against diabetes, were found to show inhibitory activities on aldose reductase and α-glucosidase and on the increase of serum glucose level in sucrose-loaded rats and in alloxan-induced diabetic mice. From the ethyl acetate-soluble portion, new flavanone glucosides, myrciacitrins I and II, and new acetophenone glucosides, myrciaphenones A and B, were isolated together with several known compounds such as five flavonol glycosides, myricitrin, mearnsitrin, quercitrin, desmanthin-1, and guaijaverin. The structures of new compounds were determined on the basis of physicochemical and chemical evidence. The principal components of this natural medicine including new glucosides, myrciacitrin I and myrciaphenone B, were found to show potent inhibitory activities on aldose reductase and α-glucosidase.View full abstractDownload PDF (1018K) -
Juziro NISHIJO, Hitomi MIZUNO1998 Volume 46 Issue 1 Pages 120-124
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe interaction of cyclodextrins (CDs) with dipalmitoylphosphatidylcholine (DPPC) liposomes had been studied using differential scanning calorimetry (DSC). The phase transition temperature and the enthalpy change due to the gel-to-liquid crystalline phase transition of the liposomes were measured in the presence of α-CD, β-CD, γ-CD, heptakis (2, 6-di-O-methyl)-β-CD (DOM-β-CD), heptakis (2, 3, 6-tri-O-methyl)-β-CD (TOM-β-CD) and 2-hydroxylpropyl β-CD, respectively. The effects on the change of enthalpy of the transition and transition temperature were remarkable in the order of DOM-β-CD>α-CD>TOM-β-CD. The residual CDs caused scarcely detectable changes in the enthalpy changes and the transition temperatures.In order to clarify the DSC curves in the presence of the CDs mentioned above, the type of interactions which occurred between CDs and DPPC liposomes were studied. Consequently, it was found that DOM-β-CD forms a soluble complex and α-CD forms an insoluble complex with DPPC liposomes, whereas only a slight amount of TOM-β-CD was suggested to penetrate the matrix of the liposomes.View full abstractDownload PDF (771K) -
Hideshi SUZUKI, Hisakazu SUNADA1998 Volume 46 Issue 1 Pages 125-130
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSNicotinamide is a hydrotropic agent that has been demonstrated to solubilize a wide variety of drugs through complexation. Past investigations on the potential interaction of nicotinamide with a solubilized drug have inadequately focused on aliphatic hydrotropes. This study examined the mechanism for the hydrotropic solubilization of nifedipine, a poorly water-soluble drug, in the aqueous solution of nicotinmide using not only nicotainamide analogues but also urea analogues as aliphatic hydrotropes. The values of stability constants, K1 : 1 and K1 : 2, at different temperatures in nicotinamide solution were determined by the phase solubility technique, and were utilized to estimate the thermodynamic parameters of complex formation between nifedipine and nicotinamide. The enthalpy change values suggested the participation of intermolecular forces other than hydrogen bonding in complexation. The aqueous solubility of nifedipine was measured in the presence of nicotinamide, urea and their analogues : N-methylnicotinamide, N, N-diethylnicotinamide, nipecotamide, methylurea, ethylurea and butylurea. The drug solubility increased in proportion to the amount of alkyl substituent on the amide nitrogen, and the solubilizing effect of butylurea was as high as that of nicotinamide. Furthermore, the relationship between the logarithmic drug solubilities in 1.0 M aqueous solutions of nicotinamide or urea analogues versus the logarithmic octanol-water partition coefficient values of ligands as an indication of hydrophobicity was found to be linear. The significant contributor to the hydrotropic solubilization of nifedipine with nicotinamide was therefore the ligand hydrophobicity rather than the aromaticity of the pyridine ring.View full abstractDownload PDF (824K) -
Yukinori KAWAI, Kyuichi MATSUBAYASHI1998 Volume 46 Issue 1 Pages 131-135
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe photodegradation reaction of (2S)-2-[4-[[(3S)-1-acetimidoyl-3-pyrrolidinyl]oxy]phenyl]-3-(7-amidino-2-naphthyl)propanoic acid hydrochloride pentahydrate (DX-9065a), a new factor Xa inhibitor, was investigated in aqueous solution at various pH values (1.1-8.0) at 25°C. The photodegradation of DX-9065a followed apparent first-order kinetics under artifical sunlight in a fairly good manner. The photodegradation rates of DX-9065a in a neutral solution were higher than those in acidic solution. The log k-pH profile indicated that the photodegradation rate of DX-9065a was related to the dissociation of the carboxyl group and suggested that the main photo-labile species was the carboxylate form. Further kinetic study showed that the carboxylate form of DX-9065a underwent decarboxylation quantitatively to produce D41-1077, the photodecarboxylation product, on irradiation, while the carboxylic acid form of DX-9065a did not perform any photodecarboxylation. Moreover, the photodecarboxylation mechanism was discussed in relation to the kinetics and photodegradation pathway.View full abstractDownload PDF (660K) -
Hiromi SUMIKAWA, Ei-ichiro SUZUKI1998 Volume 46 Issue 1 Pages 136-138
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTertiary structure models of interleukin-6 were construted using a routine prediction method based on the X-ray crystal structures of granulocyte colony-stimulating factor (GCSF) and leukemia inhibitory factor (LIF). Those models were evaluated using a sequence-structure compatibility (3D-1D) method program Compass and a limited amount of NMR distance information when it was concluded that the model based on GCSF (IBGC) was preferable to that from LIF (Sumikawa et al., FEBS Lett., 404, 234 (1997)). We evaluated the quality of this model (IBGC) by comparing with X-ray (Somers et al., EMBO. J., 16, 989 (1997)) and NMR (Xu et al., J. Mol. Biol., 268, 468 (1997)) structures. Consequently, normal mode calculations were carried out for this model, giving conformation fluctuations similar to the C alpha deviation pattern between X-ray and NMR structures.View full abstractDownload PDF (547K) -
Tetsutaro KIMACHI1998 Volume 46 Issue 1 Pages 139-141
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSDirected ortho metalation of phenyl p-toluenesulfonate (phenyl tosylate) was carried out and the reaction was found to be controlled by the conditions (base, solvent, temperature, with or without ligand) to some extent.View full abstractDownload PDF (437K) -
Nobuhiro ABE, Fumiko FUJISAKI, Kunihiro SUMOTO1998 Volume 46 Issue 1 Pages 142-144
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSPreparation of β-(sec-amino)alanines (3) by acid hydrolysis of diethyl (sec-aminomethyl)formamidomalonates (2) was studied. Although high reaction temperature resulted in low yield, low reaction temperature (below 30°C) gave good to excellent yields. The hydrolysis of diethyl formamido(piperidinomethyl)malonate (2a) was followed by 1H-NMR, and a plausible mechanism involving the condensation of ethyl hydrogen aminomalonate (7) with 1-piperidinemethanol (5) is proposed.View full abstractDownload PDF (501K) -
Masa-aki MORI, Masahiro DOHRIN, Michio SAYAMA, Miki SHOJI, Masami INOU ...1998 Volume 46 Issue 1 Pages 145-147
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSulfates and glucuronides of 2, 4-dinitrobenzyl alcohol 1a and 2, 6-dinitrobenzyl alcohol 1b, which are major or putative metabolites of 2, 4-dinitrotoluene (2, 4-DNT) and 2, 6-dinitrotoluene (2, 6-DNT), were synthesized from 1a and 1b by reaction with pyridinium sulfonate and methyl (2, 3, 4-tri-O-acetyl-α-D-glucopyranosyl)uronate bromide 3, respectively, as their pyridinium salts (2a, 2b) and potassium salts (6a, 6b). These conjugates are important for the study of the carcinogenicity of 2, 4-DNT and 2, 6-DNT.View full abstractDownload PDF (512K) -
Tadashi KATAOKA, Tetsuo IWAMA, Harutoshi MATSUMOTO, Hirohito KONDO, Yo ...1998 Volume 46 Issue 1 Pages 148-150
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSReactions of 2'-vinyl-2H-benzothiazine-2-spirocyclopropan-3(4H)-ones (1) with several proton acids were examined. Reactions of 1 with HCl and HBr predominantly gave (Z)-allyl halide derivatives (2). In the cases of HClO4 and HBF4 4, 4a, 5, 6-tetrahydro-5-oxo-1H-thiopyrano[1, 2-a]-1, 4-benzothiazinium salts (3) were isolated. Allyl halides (2) were also obtained by treatment of the salts (3) with HCl and HBr.View full abstractDownload PDF (502K) -
Tadashi KATAOKA, Tetsuo IWAMA, Harutoshi MATSUMOTO1998 Volume 46 Issue 1 Pages 151-153
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSPhotochemical thiylation of 2'-vinyl-2H-benzothiazine-2-spirocyclopropan-3(4H)-ones (1) to form allyl sulfides (3) was examined. Although the reactions proceeded with complete regioselectivity because of the high stabilizing ability of the capto-dative substituents, geometrical selectivity of the olefinic moiety was dependent on the substituents on the cyclopropane ring. The conformation of 1 probably plays an important role in the addition step of the thiyl radical to the double bond.View full abstractDownload PDF (486K) -
Shigeki SASAKI, Katsunori MARUTA, Hiroyuki NAITO, Rie MAEMURA, Eiji KA ...1998 Volume 46 Issue 1 Pages 154-158
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWe investigated the in vitro antitumor activities toward mouse and human cell lines of optically active synthetic bistetrahydrofuran (bis-THF) derivatives as analogs of Annonaceous acetogenins, which contain bis-THF, long unbranched alkyl chains, hydroxyl groups, and an α, β-unsaturated γ-lactone. These bis-THF derivatives were synthesized in a stereocontrolled manner, and have several modified structures at the alkyl side chains. We found that : 1) the unsaturated γ-lactone contributes to high potency in combination with the other less-functionalized alkyl chain, 2) the same absolute configuration of the bis-THF skeleton as that of the natural products produces more potent activity than the counterpart, 3) the alkyl chains and hydroxyl groups are crucial for exhibiting antitumor activity, 4) hydroxyl groups adjacent to the bis-THF skeleton may be replaced by amino or acylamino groups.View full abstractDownload PDF (764K) -
Haruko TAKECHI, Yasuo GOTO, Minoru MACHIDA1998 Volume 46 Issue 1 Pages 159-162
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS4-(7-Diethylaminocoumarin-3-yl)benzoyl cyanide (DACB-CN) was synthesized as a new fluorescent derivatization reagent for alcohols for use in high-performance liquid chromatography. Saturated alcohols (C8-C22) were derivatized in good yields to give the corresponding fluorescent DACB-esters by treatment with DACB-CN. The DACB-esters of these alcohols were clearly separated on a reversed-phase HPLC column. The detection limit (S/N=3) of cetyl alcohol, a test compound, was 1-2 fmol/10 μl.View full abstractDownload PDF (614K) -
Seung-Yeup CHANG, Chang-Soo YOOK, Toshihiro NOHARA1998 Volume 46 Issue 1 Pages 163-165
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo new lupane-triterpene glycosides, acankoreoside A (1) and B (2), were isolated from the leaves of Acanthopanax koreanum NAKAI (Araliaceae). Based on spectroscopic data, the chemical structures of 1 and 2 were determined as 3α-hydroxy-lup-20(29)-en-23, 28-dioic acid 28-O-α-L-rhamnopyranosyl-(1→4)-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl ester and 3α, 11α, 23-trihydroxy-lup-20(29)-en-28-oic acid 28-O-α-L-rhamnopyranosyl-(1→4)-β-D-glucopyranosyl- (1→6)-β-D-glucopyranosyl ester, respectively.View full abstractDownload PDF (569K) -
Hiroyuki FUCHINO, Tetsuya SATOH, Midori SHIMIZU, Nobutoshi TANAKA1998 Volume 46 Issue 1 Pages 166-168
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe constituents of Betula davurica PALL. were identified as follows : Fresh leaves : 12-O-acetylbetulafolieneteraol oxide, I, 5, 8-dihydroxy-6, 7-dimethoxyflavone, rutin. Outer bark : betulin, betulin 3-O-caffeate, oleanolic acid, oleanolic acid 3-O-acetate, 3β-acetoxy-12α-hydroxyoleanan-28, 13β-olide, betulinic acid 3-O-caffeate, oleanolic acid 3-O-caffeate, butulonic acid. Inner bark : acerogenin E, (3R)-3, 5'-dihydroxy-4'-methoxy-3', 4"-oxo-1, 7-diphenyl-1-hep-tene, 17-O-methyl-7-oxoacerogenin E*, 15-methoxy-17-O-methyl-7-oxoacerogenin E*, (-)-lyoniresinol 3α-O-β-D-xylopyranoside (=nudiposide), (+)-catechin, (+)-catechin 7-O-β-D-xylopyranoside, 3, 4, 5-trimethoxyphenol β-D-apiofuranosyl-(1→6)-β-D-glucopyranoside, monogynol A, roseoside. Root bark : betulin 3-O-caffeate, 3β, 27-dihydroxyolean-12-en-28-oic acid 27-O-caffeate. The two compounds with an asterisk are new.View full abstractDownload PDF (507K) -
Hiroyuki FUCHINO, Tetsuya SATOH, Mika YOKOCHI, Nobutoshi TANAKA1998 Volume 46 Issue 1 Pages 169-170
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo new seco-dammarane-type triterpenes, called ovalifoliolides A and B, were isolated from the methanol extract of fresh leaves of Betula ovalifolia together with 12-O-acetylbetulafolienetriol, (3R)-3, 5'-dihydroxy-4'-methoxy-3', 4"-oxo-1, 7-diphenyl-1-heptene and rutin. Betulin, betulin 3-caffeate, rhododendrin, (+)-catechin, (+)-catechin 7-O-β-D-xylopyranoside and procyanidin B-3 were also isolated from the bark. Their structures were determined by spectral data and chemical evidence.View full abstractDownload PDF (379K) -
Takeshi NAKANISHI, Fusao KAIHO, Masahiro HAYASHI1998 Volume 46 Issue 1 Pages 171-173
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSCarbopol 934P (CP) is a mucoadhesive polymer which has been investigated as a useful adjuvant for bioadhesive drug delivery system. However, since the drug release rate from the solid formulation of CP is slow, it is difficult to take advantage of the polymer's mucoadhesive property in oral administration of fast-acting drugs. In this study, we prepared freeze-dried sodium salt of CP (FNaCP) in order to improve drug release from the formulation of CP. The drug release rate from the formalution of FNaCP was much faster than that of CP : the rate from the formulation of CP in JP XIII 1st fluid (pH 1.2) was faster than in JP XIII 2nd fluid (pH 6.8). To determined the cause of rapid drug release from FNaCP capsules, the change of CP gel properies with pH and ionic strength was investigated. Experimental results indicated that CP forms a swollen gel layer, a drug release barrier between the formulation of CP and the bulk release media. FNaCP was also though to disperse rapidly in the 1st and 2nd fluids without formation of the swollen gel layer. In conclusion, since FNaCP improves the drug release rate from the solid CP formulation, it could be a useful adjuvant of an oral bioadhesive drug delivery system.View full abstractDownload PDF (513K) -
Ae-Ri Cho LEE, Kakuji TOJO1998 Volume 46 Issue 1 Pages 174-177
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA mechanism for the relatively high permeability of vitamin C in relation to the change in the protein domain of the stratum corneum has been proposed. Firstly, the skin permeation characteristics of vitamin C (l-[1-14C]-ascorbic acid) using whole skin and stripped skin of the hairless mouse were investigated. By employing a double layer model, physicochemical properties such as diffusivity and solubility of vitamin C in each skin layer, stratum corneum and viable skin were determined. Then, the high skin permeation rate of vitamin C was characterized. A differential scanning calorimetry, (DSC), study was employed to investigate the effect of vitamin C on the stratum corneum, a major diffusion barrier for the skin transport of the compound.Vitamin C was found to permeate rapidly through the skin, in spite of its low lipophilicity. The diffusivity determined from the lag-time was approximately 1000 times higher in the stripped skin, compared with whole skin. There is a dramatic increase (10-fold) in the permeation rate in stripped skin indicating the major barrier presented by the stratum corneum to the skin permeation of vitamin C.The DSC profile showed four very distinctive transitions near 100, 128, 135 and 145°C which are associated with protein transitions. Comparing normal skin, the peaks are sharpened and there are additional phase transitions above 90°C. An increase in sharpness reflects an increase in the hydration state of the sample, as hydrogen bonds between H2O molecules and other hydrogen donating chemicals of skin components become major chemical bonds in hydrated samples. The higher permeation rate of vitamin C observed may be due to its enhancing effect on the hydration capacity of skin and solubilizing action on the protein domain of the stratum corneum.View full abstractDownload PDF (675K) -
Masao TOYOTA, Tetsuya SAITO, Yoshinori ASAKAWA1998 Volume 46 Issue 1 Pages 178-180
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe diethyl ether extract of Pallavicinia subciliata yielded unique skeletal diterpenoids in addition to the previously known compound. The structures of six new diterpenoids have been established by 2D NMR and/or X-ray crystallographic analysis. They are shown to be a modified labdane-type diterpenoid.View full abstractDownload PDF (415K) -
Yueh-Hsiung KUO, Chia-Hsien CHEN, Shou-Ling HUANG1998 Volume 46 Issue 1 Pages 181-183
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSObtunone, a novel bicyclo[2. 2. 2]octane skeleton diterpene, was isolated from the heartwood of Chamaecyparis obtusa var. formosana. Its structure was determined spectroscopically by interpretation of 2D-NMR experiments, including HMBC and NOESY.View full abstractDownload PDF (412K) -
Yasutomi ASANO, Akira IIDA, Kiyoshi TOMIOKA1998 Volume 46 Issue 1 Pages 184-186
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe conjugate addition reaction of BHA alkenoates with butyl- and phenyllithiums in toluene at -78°C were catalyzed by a substoichiometric amount of chiral ligands 1 and 2 to give the corresponding 3-substituted alkanoates in good to modest ees.View full abstractDownload PDF (419K) -
Munetaka KUNISHIMA, Daisuke NAKATA, Kazuhito HIOKI, Shohei TANI1998 Volume 46 Issue 1 Pages 187-189
Published: January 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSPartial reduction of dithioacetals to the corresponding sulfides was effected by samarium iodide in the presence of either t-BuOH or acetic acid in benzene-HMPA. An α-sulfenyl anion was shown to be involved.View full abstractDownload PDF (449K)
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