-
Hiromi SUMIKAWA, Ei-ichiro SUZUKI, Ken-ichi FUKUHARA, Yasushi NAKAJIMA ...
1998 Volume 46 Issue 7 Pages
1069-1077
Published: July 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL
FREE ACCESS
In this study, granulocyte colony-stimulating factor (GCSF) proteins were chosen as subjects for normal mode analysis. As helical cytokines with a four helix bundled type topology, they were classified into long chain and short chain groups by Sprang and Bazan. Normal mode calculations were also carried out with leukemia inhibitory factor (LIF), interleukin-6 (IL-6), and growth hormone (GH) as members of the long chain group and GCSF and IL-2 and IL-4 as members of the short chain group. For the GCSF families it was found that the fluctuations in the helical region are smaller than in the loop region, and it is clear that on the whole the smaller fluctuation residues belong to a large hydrophobic core region. Thus, it can be imagined how the receptor binding sites approach the receptor within the normal time-scale of pico seconds. In addition, two similar domain-type motions in low frequency modes were found with proteins in the chain group, although we never observed any sequence similarity in the two separate two-domain regions in each protein of the long chain group. On the other hand, these two domain-type motions were not clear in proteins of the short chain group.
View full abstract
-
Yoshitsugu ARAI, Tsutomu MASUDA, Yukio MASAKI
1998 Volume 46 Issue 7 Pages
1078-1083
Published: July 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL
FREE ACCESS
Two types of chiral sulfoxides as Diels-Alder dienophiles were synthesized and high levels of diastereoselectivity were observed in cycloadditions. 2-Furyl and 2-thienyl α, β-enones, bearing a chiral sulfinyl group in the heterocycle, served as efficient dienophiles in Diels-Alder reactions, where the catalytic use of aluminium chloride or a lanthanide triflate effected the cycloaddition with cyclopentadiene affording the endo adduct with high diastereoselectivity, ranging from 91% to 98%.
View full abstract
-
Masazumi IKEDA, Ken-ichi HIROSE, Serry A.A. EL BIALY, Tatsunori SATO, ...
1998 Volume 46 Issue 7 Pages
1084-1089
Published: July 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL
FREE ACCESS
1-[2-(o-Iodophenyl)acetyl]-2-(prop-2-enyl)-2-vinylpyrrolidine (17), upon treatment with palladium(II) acetate [Pd(OAc)
2] in the presence of triphenylphosphine and triethylamine in refluxing acetonitrile, gave the monocyclization product 20 as the major product along with a small amount of the tandem cyclization product 21. On the other hand, treatment of the 1-[2-(o-iodophenyl)acetyl]-1-azaspiro[4.4]non-8-en-7-one (25) with Pd(OAc)
2, 1, 3-bis-(diphenylphosphino)propane, tributylphosphine, and silver carbonate in boiling N, N-dimethylformamide afforded the cyclized product 27 in 51% yield.
View full abstract
-
Jun'ichi UENISHI, Reiko KAWAHAMA, Takahiro IMAKOGA, Osamu YONEMITSU
1998 Volume 46 Issue 7 Pages
1090-1093
Published: July 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL
FREE ACCESS
The perchloric acid-promoted transformation of (-)-ircinianin (1) to (+)-wistarin (2) is described. The reaction of 1 with perchloric acid in acetonitrile gave 2 in 35% yield along with a positional isomer 4 in 35% yield. The structure of 4 was determined by two dimensional (2D) NMR studies. On the other hand, the reaction of 2-methyl-4-prenyltetronic acid (6), as a model compound for the above transformation, gave the cyclized product 8 corresponding to 2 in 58% yield and the keto-lactone 9 in 22% yield under the same conditions.
View full abstract
-
Taisuke ITAYA, Yoshitaka HOZUMI
1998 Volume 46 Issue 7 Pages
1094-1101
Published: July 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL
FREE ACCESS
Phenyl, tolyl, anisyl, and 1-naphthyl iodides (7a-g, n) smoothly reacted with (S)-N-(benzyloxycarbonyl)-vinylglycine (6) in H
2O in the presence of Pd(OAc)
2, Bu
4NCl, and NaHCO
3 at 45°C, producing [S-(E)]-(2-arylvinyl)glycine derivatives 8a-g, n of high enantiomeric purity. The yields of the reactions of 3- (7f), 2- (7e), and 4-iodoanisoles (7g) increased in this order. This relationship between the yield and the position of substitution has been found to hold for bromophenyl iodides (7i-k), although somewhat lower chemical and optical yields were realized in these cases. Phenyl iodide 7l carrying an electron-withdrawing 4-acetyl group gave an unsatisfactory result, and more electron-deficient 4-nitrophenyl iodide (7m) did not provide the desired product. All these results suggest that the reaction is advantageous with electron-sufficient substrates 7. However, this was not the case for 4-iodophenol (7h), as well as some heterocyclic iodides.
View full abstract
-
Kazuko YOSHIKAWA, Hiroki OGATA, Shigenobu ARIHARA, Hsen-Chang CHANG, J ...
1998 Volume 46 Issue 7 Pages
1102-1107
Published: July 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL
FREE ACCESS
From the dried roots of Gymnema alternifolium, ten new oleanane-type triterpenoid glycosides, named alternosides I-X (1-10), were isolated, as well as two artifactual compounds, 11 and 12. Their structures were determined on the basis of spectroscopic data and chemical evidence. Compounds 1-5, and 6, 8 and 10 are 3, 28-bis-O-glycosides of chichipegenin having an acyl group at position 16 or 18, and no acyl group, respectively.Compound 7 is 3-O-glycoside of chichipegenin. Compound 9 consists of the 3, 28-bis-O-glycosides of longispinogenin.Compounds 1-5 and 11, having an acyl group, showed antisweet activity.
View full abstract
-
Shigeki KOBAYASHI, Hajime HAMASHIMA, Masaaki KURIHARA, Naoki MIYATA, A ...
1998 Volume 46 Issue 7 Pages
1108-1115
Published: July 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL
FREE ACCESS
We found that absolute hardness-absolute electronegativity (η-χ) activity diagrams play an important role as a new coordinate of bioactivity in structure-activity relationships. In this paper, the η-χ activity diagram, focusing on the molecular mechanism of bioactive compounds is used to discuss two major problems. First, the potency of bioactivities for xenobiotics such as polychlorinated dibenzo-p-dioxins (PCDDs) 3 and polychlorinated biphenyls (PCBs) 4, were found to be strongly related to their absolute hardness (η). Second, the antibacterial activity of new quinolones such as norfloxacin 1 and enoxacin 2, was found to be strongly related to their absolute electronegativity (χ). These findings predict at least two chemical properties for a hardness-controlled or electronegativity-controlled enzyme.
View full abstract
-
Takeshi SUZUKI, Naoki IMANISHI, Hirotsune ITAHANA, Susumu WATANUKI, Ke ...
1998 Volume 46 Issue 7 Pages
1116-1124
Published: July 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL
FREE ACCESS
A novel series of 4-amino-N-[2-(1-aminocycloalkan-1-yl)ethyl]-5-chloro-2-methoxybenzamide derivatives (1), which had amines conformationally restricted due to the effect of repulsion by neighboring substituents, were prepared and evaluated for 5-hydroxytryptamine 4 (5-HT
4) agonistic activities by using the contraction of longitudinal muscle myenteric plexus (LMMP) of guinea pig ileum. One of the most potent compounds in this series was 4-amino-5-chloro-N-[2-(1-dimethylamino-1-cyclohexyl)ethyl]-2-methoxybenzamide (1c, YM-47813) with an EC<50> value of 1.0 μM on LMMP. This compound effectively enhanced gastric motility and gastric emptying in conscious dogs by oral administration (1-3 mg/kg).
View full abstract
-
Yumiko KAKU, Akihiko TSURUOKA, Hiroyuki KAKINUMA, Itaru TSUKADA, Manab ...
1998 Volume 46 Issue 7 Pages
1125-1129
Published: July 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL
FREE ACCESS
A novel synthetic route to (2S, 3S)-2-(2, 4-difluorophenyl)-3-hydroxy-2-methyl-4-(1-(1, 2, 4-triazolyl))butyronitrile (2), an intermediate for the orally active triazole antifungal agent ER-30346, was developed from methyl S-(+)-3-hydroxy-2-methylpropionate, a commercially available chiral compound. The second chiral center was constructed with 6.4 : 1 diastereoselectivity via osmium tetroxide catalyzed dihydroxylation.
View full abstract
-
Atsuo BABA, Haruhiko MAKINO, Yoshikazu OHTA, Takashi SOHDA
1998 Volume 46 Issue 7 Pages
1130-1134
Published: July 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL
FREE ACCESS
The metabolites of ethyl 4-(3, 4-dimethoxyphenyl)-6, 7-dimethoxy-2-(1, 2, 4-triazol-1-ylmethyl)quinoline-3-carboxylate (1, TAK-603), which is under clinical evaluation as a new type of disease-modifying antirheumatic drug (DMARD), were prepared to confirm their structures and to study their pharmacological properties. Of the metabolites identified, the 4-(4-hydroxy-3-methoxyphenyl) derivative (2c, M-I) was found to have an anti-inflammatory effect in an adjuvant arthritic rat model, although its potency in this model was slightly lower than that of the parent compound.
View full abstract
-
Magoichi SAKO, Hikokazu SUZUKI, Kosaku HIROTA
1998 Volume 46 Issue 7 Pages
1135-1139
Published: July 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL
FREE ACCESS
UV-Irradiation of taxinine and related compounds in acetonitrile induced a smooth transannulation between the C-3 and C-11 positions without any influence from the C-2, C-9 and C-10 substituents to give tetracyclic taxuspine C derivatives in almost quantitative yields. Photochemical transannular reaction of taxoids possessing a cinnamoyl group in the side-chain was accompanied by an E, Z-isomerization of the cinnamoyl moiety. Cellular accumulation of vincristine, a useful drug for cancer chemotherapy, in multidrug-resistant ovarian cancer cells was found to increase most effectively in the case of 5-O-benzoylated 5-O-decinnamoyltaxuspine C. This indicates that the 5-O-benzoylated taxuspine C derivative may be a promising functional inhibitor of P-glycoprotein, which acts as an ATP-associated efflux pump for cancer chemotherapeutic agents.
View full abstract
-
Da-Woon JUNG, Masaaki SHIBUYA, Yutaka EBIZUKA, Kayo YOSHIMATSU, Koichi ...
1998 Volume 46 Issue 7 Pages
1140-1143
Published: July 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL
FREE ACCESS
In order to quantify saikosaponin a (SSA), one of the major active components of Bupleuri Radix, a competitive and indirect ELISA method was developed.High titer rabbit polyclonal antibodies (pAbs) were raised against a conjugate of SSA and bovine serum albumin, coupled with a periodate oxidation method. SSA competitively inhibited the binding of rabbit anti-SSA pAbs to SSA-ovalbumin on the solid phase, a coated antigen on the well. The quantity of pAbs bound to the well was monitored using a peroxidase-conjugated anti-rabbit IgG as a secondary antibody, and tetramethylbenzidine solution as a substrate. The measuring range extended from 50 pg/ml to 20 ng/ml of SSA, with a detection limit of 40 pg/ml (5.13 pM). Antibodies showed some cross-reactivity with saikosaponin c (12.74%). However, the antibodies showed only slight cross-reactivities with saikosaponin d (0.3%), which differs from SSA only in the stereochemistry of the 16-hydroxyl group, and the artificial saikosaponins, saikosaponin b
1 (2.1%) and saikosaponin g (0.53%). The specific and sensitive ELISA is especially suited for determination of SSA in samples when only small quantities of materials can be extracted for analysis.
View full abstract
-
So-Rah YOON, Jin-Ju NAH, Si-Kwan KIM, Seok-Chang KIM, Ki-Yeul NAM, Da- ...
1998 Volume 46 Issue 7 Pages
1144-1147
Published: July 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL
FREE ACCESS
We have developed an enzyme immunoassay (EIA) to quantify trace amounts of ginsenoside Rf (Rf), one of the glycosides of protopanaxatriol from Panax ginseng. A carrier protein of bovine serum albumin (BSA) was coupled to the carbohydrate component of Rf using the periodate oxidation method. Antibodies were raised in rabbits using Rf-BSA conjugate as the immunogen and competitive indirect EIA was used for the determination of Rf. The working range was 0.01-10 ng per assay. The anti-Rf antiserum cross-reacted with ginsenoside Rg
2 (105%), which is also a component of Panax ginseng and has a very similar chemical structure to Rf. These results suggest that the anti-Rf antiserum could also be used for the quantitation of ginsenoside Rg
2 as well as ginsenoside Rf. In a comparison of EIA and HPLC the linear regression equation and correlation coefficient for the two methods were y(EIA)=1.31x (HPLC)-11.48 and 0.98, respectively.
View full abstract
-
Yasuo YOSHIHASHI, Midori MAKITA, Shigeo YAMAMURA, Eihei FUKUOKA, Katsu ...
1998 Volume 46 Issue 7 Pages
1148-1152
Published: July 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL
FREE ACCESS
Heat of hydration of theophylline anhydrate to the monohydrate at 298 K was evaluated by three different methods. The values determined by heat of solution with a microcalorimeter and heat of dehydration with a differential scanning calorimeter were -9.34±0.65 and -9.82±0.48 kJ/mol, respectively. The values obtained directly with a heat conduction microcalorimeter under 97.3, 95.4 and 93.7% relative humidities were -9.48±0.49, -9.28±0.63 and -9.37±0.74 kJ/mol, respectively. From thermograms obtained with a microcalorimeter at the isothermal transition of theophylline anhydrate to monohydrate, hydration rates were analyzed by a deconvolution method.Hydration rates were in good agreement with those obtained by the Karl Fischer method. Hydration mechanisms were also analyzed on the basis of solid-state kinetic models and the transition followed a mechanism of random nucleation and two-dimensional growth of nuclei.
View full abstract
-
Masanori INAGAKI, Yasuo HARADA, Koji YAMADA, Ryuichi ISOBE, Ryuichi HI ...
1998 Volume 46 Issue 7 Pages
1153-1156
Published: July 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL
FREE ACCESS
Five cerebrosides, AS-1-1 (1), AS-1-2 (2), AS-1-3 (3), AS-1-4 (4), and AS-1-5 (5) were obtained from the CHCl
3-MeOH extract of Garlic, the bulbs of Allium sativum L. (Liliaceae). On the basis of spectroscopic results, structures of 1-5 have been elucidated. Compounds 1, 2, and 5 were new cerebrosides. Compounds 3 and 4 were identified with the known glucocerebroside soya-cerebroside I and II, respectively, which have been previously obtained from soybean with ionophoretic activity. Positive ion FAB-MS/MS of the (M+Na)
+ ion gave important information on the length of the fatty acyl chain of the ceramide moiety.
View full abstract
-
Masaki NODA
1998 Volume 46 Issue 7 Pages
1157-1159
Published: July 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL
FREE ACCESS
The facile synthesis of 3-methoxy-10, 11-dihydro-5H-dibenzo[a, d]cyclohepten-5-one (5) via m-methoxystilbene-2-carboxylic acid (3) was developed for the preparation of the mild acid labile peptide amide linker containing 10, 11-dihydro-5H-dibenzo[a, d]cyclohepten-5-yl group for Fmoc (9-Fluorenylmethoxycarbonyl)-solid phase peptide synthesis.
View full abstract
-
Hiroshi HARADA, Toshiya MORIE, Shiro KATO
1998 Volume 46 Issue 7 Pages
1160-1164
Published: July 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL
FREE ACCESS
An efficient and practical method for large scale synthesis of (R)-6-benzyloxycarbonylamino-1-methyl-4-(3-methylbenzyl)hexahydro-1, 4-diazepine (R-3), which is a key intermediate in the synthesis of DAT-582, a potent and selective serotonin-3 receptor antagonist, is described. The precursor of R-3, the (S)-2, 3-diaminopropylaminoacetate S-5, was obtained from the chiral triaminopropane derivative R-19. Nucleophilic reaction of the chiral mesylate R-11 with 3-methylbenzylamine gave the racemic 2, 3-diaminopropylaminoacetate (±)-5 via the achiral azetidinium cation 12, while the reaction of the N-protected mesylate R-14 produced the desired triamine S-15 but in poor yield.However, reaction of the N-protected mesylate S-18 with a large excess of methylamine proceeded smoothly to afford R-19 in good yield. S-5 was converted into R-3 with >99% enantiomeric excess using an intramolecular reductive cyclization method.
View full abstract
-
Hiroyuki MIYACHI, Yukiko KOISO, Ryuichi SHIRAI, Satomi NIWAYAMA, Jun O ...
1998 Volume 46 Issue 7 Pages
1165-1168
Published: July 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL
FREE ACCESS
The synthesis and tumor necrosis factor (TNF)-α production enhancing activity of substituted 3'-methyl-thalidomides on human leukemia cell line HL-60 stimulated with 12-O-tetradecanoyl-phorbol 13-acetate (TPA) are described. Though the introduction of an electron-donating amino group at the phthaloyl moiety of α-methylthalidomides enhanced the activity, substituted α-methylthalidomides showed decreased stereoselectivity as compared to that of non-substituted α-methylthalidomide. The data indicates that the TNF-α production enhancing activity of thalidomide derivatives depends on both the electronic-state of substituents at the fused benzene ring and the stereochemistry of the glutarimide moiety.
View full abstract
-
Koichi TAKAO, Toshihisa IGARASHI, Hironao OGISO, Kazuya UGATA, Akira S ...
1998 Volume 46 Issue 7 Pages
1169-1172
Published: July 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL
FREE ACCESS
Synthetic polyamines and various derivatives of aspartic acid and glutamic acid were examined in vitro for their inhibitory activity on arginyl-tRNA-protein transferase. All the polyamines tested showed non-specific activation or inhibition at 0.1 or 10 mM, respectively, suggesting an interaction of polyamines with tRNA. Of the newly prepared active site directed compounds including the inhibitory peptides so far reported, L-aspartic acid α-[(S)-(-)-naphthylethylamide] was found to inhibit the enzyme activity most potently with a slight substrate activity, whereas the R-isomer showed very weak inhibition, giving information on the active site of the enzyme.
View full abstract
-
Yuki TAKASHIMA, Hiroshi YUASA, Yoshio KANAYA
1998 Volume 46 Issue 7 Pages
1173-1176
Published: July 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL
FREE ACCESS
In our previous paper, we developed intragastric floating and sustained release granules using the characteristically porous structure of calcium silicate. In this paper, we investigated the preparation of floating granules using hollow glass beads (GB, density 0.15 g/cm
3) as a carrier and introducing them to the solid dispersion in order to produce a higher floating ability. A 20/5/75 weight ratio of oxprenolol hydrochloride (OXP) as a model drug, hydroxypropylcellulose (HPC) and ethylcellulose (EC) was dissolved in ethanol. Zero, 20, 40, 60 and 80 weight percent of GB to the total weight of OXP, HPC and EC were added to the ethanol solution, and the solvent was then evaporated by rotating the vessel at 50°C. Several types of solid dispersion which contain suspended and dispersed GB were obtained. The granules having different GB contents were obtained after being dried at 80°C in vacuo and were crushed using a coffee mill for sieving. The density, floating property and drug release profile of the granules were than studied. The density of granules without GB, namely the solid dispersion granules, was 1.18 g/cm
3 and therefore did not have floating properties. The densities of all types of granules containing GB were less than 1 g/cm
3 and these granules floated for a long time in the floating test. It was found that release rates of OXP from granules decreased with decreasing GB content, since the surface area of granules was decreased and a thick layer of solid dispersion was formed. These results suggest that it is possible to prepare floating granules by using GB.
View full abstract
-
Yoshihiro SAITO, Izumi TANEMURA, Haruhisa UEDA, Takatoshi SATO
1998 Volume 46 Issue 7 Pages
1177-1179
Published: July 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL
FREE ACCESS
The simultaneous determination of the stability constants for the inclusion of fragrance materials with 2-hydroxypropyl-β-cyclodextrin (2HP-β-CyD) was investigated in a mixed fragrance materials system using static head-space gas chromatography (SHSGC). The 1 : 1 stability constants obtained by this method are in reasonable agreement with the corresponding values in the literature. The time required for determination of the stability constant is markedly reduced by this method.
View full abstract
-
Hideaki OTSUKA, Kaori KOTANI, Masahiko BANDO, Masaru KIDO, Yoshio TAKE ...
1998 Volume 46 Issue 7 Pages
1180-1181
Published: July 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL
FREE ACCESS
A novel dimeric butenolide called glochidiolide was isolated from the leaves of Glochidion acuminatum. Its structure was elucidated by X-ray analysis.
View full abstract
-
Takayuki YAKURA, Akiharu UEKI, Yukiko MORIOKA, Toyoshige KURATA, Kenji ...
1998 Volume 46 Issue 7 Pages
1182-1183
Published: July 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL
FREE ACCESS
Methyl (S)-2-diazo-4-(3, 3-dimethyl-2, 4-dioxolan-1-yl)-3-oxobutanoate (1), upon treatment with Rh
2(OAc)
4 in boiling dichloromethane, gave methyl (1S, 5S)-2, 2-dimethyl-7-oxo-3, 8-dioxabicyclo[3.2.1]octane-1-carboxylate (2) via oxonium ylide formation/1, 2-shift. On the other hand, similar treatment of methyl (S)-5, 6-bis(tert-butyldimethylsilyloxy)-2-diazo-3-oxohexanoate (3a) gave methyl 3-(tert-butyldimethylsilyloxy)-5-oxo-1-cyclopentene-1-carboxylate (4a) via the C-H insertion reaction.
View full abstract
-
Fumihiro NAGASHIMA, Makoto SUZUKI, Shigeru TAKAOKA, Yoshinori ASAKAWA
1998 Volume 46 Issue 7 Pages
1184-1185
Published: July 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL
FREE ACCESS
Two new peroxy cuparene-type sesquiterpenoids, a new 8, 9-seco-labdane-type diterpenoid and previously known compounds, have been isolated from the diethyl ether extract of Jungermannia infusca and their structures elucidated from 2D NMR and/or X-ray crystallographic analysis.
View full abstract
-
Masayuki YOSHIKAWA, Toshiyuki MURAKAMI, Toshio MORIKAWA, Hisashi MATSU ...
1998 Volume 46 Issue 7 Pages
1186-1188
Published: July 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL
FREE ACCESS
New carabrane-type sesquiterpenes, curcarabranols A and B, were isolated from zedoary together with the two known carabrane-type sesquiterpenes curcumenone and 4S-dihydrocurcumenone. The absolute stereostructures of these carabrane-type sesquiterpenes were determined on the basis of physicochemical and chemical evidence. Zedoary sesquiterpenes including 4S-dihydrocurcumenone and curcarabranols A and B were found to inhibit the contraction induced by a high concentration of K
+ in isolated rat aortic strips.
View full abstract