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Volume 46, Issue 4
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Naotake OGAWA, Hiroyuki TAGUCHI, Yoshihiro HONDA, Takatoshi SATO1998 Volume 46 Issue 4 Pages 555-558
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS2-Benzoyloxyethy vinyl ether (BOEVE) was cationically polymerized with the hydrogen iodide/zinc iodide (HI/ZnI2) initiating system in toluene at -15°C to form a narrow molecular weight distribution (MWD). The poly(BOEVE) obtained had a narrow MWD (Mw/Mn<1.2, Mw : weight-average molecular weight, Mn : number-average molecular weight). The Mn of the poly(BOEVE) increased directly in proportion to the BOEVE conversion and to the reciprocal of the initial HI concentration, that is, the reaction was found to be a living polymerization. The hydrolysis rate of the polymer in the alkaline dioxane-water system decreased with increase in the Mn of the polymer.View full abstractDownload PDF (603K) -
Hideaki MURATAKE, Naoshige MATSUMURA, Mitsutaka NATSUME1998 Volume 46 Issue 4 Pages 559-571
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAn asymmetric total synthesis of natural (+)-duocarmycin SA (1) starting from L-malic acid (7) was achieved as shown in Chart 5, establishing firmly the absolute configuration of 1. In order to find suitable reaction conditions for the key step, i.e., the formation of an alkoxyindole derivative, model compounds 9 and 40 were synthesized and two acetalization conditions using i) 2-ethyl-2-methyl-1, 3-dioxane and boron trifluoride etherate, and ii) 1, 3-bis(trimethylsilyloxy)propane and trimethylsilyl triflate were found to be effective. The former conditions were successfully applied to the total synthesis and 49b was prepared from 48 in 54% yield. Further elaborations including i) Curtius rearrangement of 53b to 56, and ii) cleavage of the primary benzyloxy group in the Presence of the secondary one in its close vicinity (56→57) led to the relay compound 62, whose conversion to 1 has already been accomplished.View full abstractDownload PDF (2232K) -
Chen ZHANG, Yasuhiro MAEDA, Yoshiro SATO1998 Volume 46 Issue 4 Pages 572-576
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe reaction of N, N-dialkyl-N-(trimethylsilyl)methyl-γ-(methoxycarbonyl or cyano)allylammonium salts (1e, g, h) with cesium fluoride in N, N-dimethylformamide (DMF) did not form the expected allyl rearrangement products 3 of N-methylides 2, and instead gave N, N-dialkyl-3-(methoxycarbonyl or cyano)-2-(fluoromethyl)propylamines (9e, g, h) as the main product. The reaction mechanism is discussed.View full abstractDownload PDF (891K) -
Masumi TAKEMOTO, Kazuo ACHIWA1998 Volume 46 Issue 4 Pages 577-580
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA novel method for producing optically active pyridyl alcohols from the corresponding racemates was developed. When racemic pyridyl alcohol is incubated with Catharanthus roseus cell cultures, chiral alcohol is obtained in high yield with excellent enantiomeric excess (ee) (deracemization of racemate). Furthermore, the kinetic resolution of racemic pyridyl alcohol via oxidation gave the chiral compound with high ee.View full abstractDownload PDF (594K) -
Hiroshi KUWAJIMA, Yoshitaka TAKAI, Kiyokazu TAKAISHI, Kenichiro INOUE1998 Volume 46 Issue 4 Pages 581-586
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIn order to clarify the biosynthetic pathway of C6-C2 unit compounds containing salidroside, cornoside, and rengyosides A and B in oleaceous plants, 13C-labeled putative precursors, 4-hydroxyphenylethanol, salidroside and cornoside, were prepared.View full abstractDownload PDF (1062K) -
Koji SATOH, Akihiro IMURA, Akihiko MIYADERA, Kazuaki KANAI, Yusuke YUK ...1998 Volume 46 Issue 4 Pages 587-590
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAn efficient synthesis method for the C-7 substituent of DU-6859a (1), which is a new-generation antibacterial quinolone carboxylic acid, was established by utilizing an enantioselective microbial reduction of 5-benzyl-4, 7-dioxo-5-azaspiro[2.4]heptane (7) to the corresponding chiral alcohol (8) as the key reaction. This synthetic method was based on use of AIPHOS (Artificial Intelligence for Planning and Handling Organic Synthesis), which is a synthesis design system that generates suitable retrosynthetic routes from the standpoints of both novelty and practicality.View full abstractDownload PDF (651K) -
Malin GRAFFNER-NORDBERG, Karin SJODIN, Anders TUNEK, Anders HALLBERG1998 Volume 46 Issue 4 Pages 591-601
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSOne way to minimise systemic side effects of drugs is to design molecules, soft drugs, in such a way that they are metabolically inactivated rapidly after having acted on their pharmacological target. Hydrolases (esterases, peptidases, lipases, glycosidases, etc.) are enzymes well suited to use for drug inactivation since they are ubiquitously distributed. Insertion of ester bonds susceptible to enzymatic cleavage may represent one approach to make the action of a drug more restricted to the site of application.The present study describes the chemical synthesis of fourteen model compounds comprising a bicyclic aromatic unit connected by an ester-containing bridge to another aromatic ring. Initial attempts to define a) the tissue selectivity of the hydrolytic metabolism and b) the molecular structural factors affecting the rate of enzymatic ester cleavage are presented.The data show that human and rat liver fractions were more active than human duodenal mucosa and human blood leukocytes at a hydrolysing the compounds. The rank order of the compounds was, however, very similar in the different biological systems. Commercially available pig liver carboxyl esterase and cholesterol esterase both reasonably well predict the rank order in the tissue fractions.View full abstractDownload PDF (1651K) -
Haruhiko HORINO, Tetsuya MIMURA, Katsuji KAGECHIKA, Masahiro OHTA, Hid ...1998 Volume 46 Issue 4 Pages 602-609
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA series of 3, 4-dihydro-3-hydroxy-4-[(5-oxo-3, 4-diazabicyclo[4.1.0]hept-2-en-2-yl)oxy]-2H-1-benzopyrans and their analogues were synthesized and evaluated on potassium channel opening and hypotensive activities. Compound (-)-13B with a (4-methyl-5-oxo-3, 4-diazabicyclo[4.1.0]hept-2-en-2-yl)oxy group for the 4-position of the benzopyran ring was 3 times as potent as EMD 57283 (II), the lead compound, in hypotensive activity. The results would demonstrate that 5-oxo-3, 4-diazabicyclo[4.1.0]hept-2-en-2-yloxy moieties are effective as the substituents at the 4-position of benzopyran-type potassium channel openers.View full abstractDownload PDF (978K) -
Yasuo SEKINE, Nobuhiko HIRAKAWA, Noriaki KASHIWABA, Hajime MATSUMOTO, ...1998 Volume 46 Issue 4 Pages 610-615
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIn an attempt to develop new types of anti-ulcer agents, a series of N-(phenoxypropyl)acetamide derivatives with a thioether moiety and their sulfur-oxidized analogues were synthesized and evaluated for histamine H2-receptor antagonistic activity, Ca antagonisitic activity and gastric anti-secretory activity in the lumen-perfussed rat. Selected compounds were also tested for gastroprotective activity, which was expected to be based on Ca antagonistic activity. Structure-activity relationships are discussed. As a thioether moiety, -CH2-S(O)p-CH2-Ar (Ar; phenyl or furyl) was found to be optimal for the above activities. Especially, N-[3-[(3-(piperidinomethyl) phenoxy]propyl]acetamide with a banzyl sulfinyl, benzylsulfonyl, furfurylsulfinyl or furfurylsulfonyl group showed potent gastroprotective activity upon oral administration in a rat model. These compounds are candidates for novel anti-ulcer drugs with gastric anti-secretory and gastroprotective activities. 2-Furfurylsulfinyl-N-[3-[(piperidinomethyl)phenoxy]propyl]-acetamide was the most potent among the compounds tested and was given the code designation FRG-8701.View full abstractDownload PDF (921K) -
Nobuhiko HIRAKAWA, Hajime MATSUMOTO, Akihiko HOSODA, Akihiro SEKINE, T ...1998 Volume 46 Issue 4 Pages 616-622
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWe recently found that N-[3-[3-(piperidinomethyl)phenoxy]propyl]acetamide derivatives with a thioether function showed gastric anti-secretory and gastroprotective activities and that the thioether function (particularly furfurylthio or furfurylsulfinyl) was essential for gastroprotection. In the present study, a series of 2-furfurylthio and 2-furfurylsulfinyl acetamide derivatives were synthesized and evaluated for histamine H2 receptor antagonistic activity, gastric anti-secretory activity and gastroprotective action. Based on the structure of N-[3-[3-(piperidinomethyl)phenoxy]propyl]acetamide, we designed compounds, in which the 3-(piperidinomethyl)phenoxy part is substituted with many types of heteroaromatic ring attached to the tertiary amine and the propyl group is replaced with other carbon linkages. Structure-activity relatioship are discussed. 2-Furfurylsulfinyl-N-[4-[4-(piperidinomethyl)-2-pyridyloxy]-(Z)-2-butenyl]acetamide was the most potent among the tested compounds and was given the code designation FRG-8813.View full abstractDownload PDF (964K) -
Akihiko TSURUOKA, Yumiko KAKU, Hiroyuki KAKINUMA, Itaru TSUKADA, Manab ...1998 Volume 46 Issue 4 Pages 623-630
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA series of novel thiazole-containing triazole antifungals was synthesized and evaluated for antifungal activity against a variety of clinically isolated pathogenic fungi in vitro and against systemic candidosis in vivo. These compounds showed potent antifungal activities in vitro and in vivo. In particular, (2R, 3R)-3-[4-(4-cyanophenyl)thiazol-2-yl]-2-(2, 4-difluorophenyl)-1-(1H-1, 2, 4-triazol-1-yl)-2-butanol (12g; ER-30346) showed potent and well-balanced in vitro activities and potent in vivo efficacy, and had a good safety profile.View full abstractDownload PDF (1372K) -
Masahiro FUJITA, Katsumi CHIBA, Junji NAKANO, Yukio TOMINAGA, Jun-ichi ...1998 Volume 46 Issue 4 Pages 631-638
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS7-(3-Amino-1-propynyl)-1-cyclopropyl-6, 8-difluoro-1, 4-dihydro-4-oxoquinoline-3-carboxylic acid (7a) and some related compounds (7b-f, 8a, b, 9) were prepared via palladium(0)-catalyzed cross-coupling reaction of 7-iodoquinolone 12 with acetylenic compounds and their antibacterial activity was tested. The methylene homologue (7d) and the N-methyl derivative (7e) of 7a showed essentially the same activity as that of 7a. Addition of methyl group(s) to C'-3 of 7a (giving 7b, c) reduced the activity. The hydrogenation of 7a to (Z)-3-amino-1-propenyl (8a), (E)-3-amino-1-propenyl (8b) and 3-amino-1-propyl (9) compounds retained or enhanced the activity of 7a. Among the compounds prepared, 8a was the most active, but was less active than ciprofloxacin (1). In order to get insight into structure-activity relationships, the spatial distribution of the amino groups of 7a, 8a, b, and 9 was examined by means of computer-aided molecular modeling.View full abstractDownload PDF (1149K) -
Naoki TANAKA, Riki GOTO, Rie ITO, Miho HAYAKAWA, Taketoshi OGAWA, Koic ...1998 Volume 46 Issue 4 Pages 639-646
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA series of [2-(ω-phenylalkyl)phenoxy]alkylamines was synthesized and their 5-hydroxytryptamine2 (5-HT2) and/or dopamine2 (D2) receptor antagonistic activities were examined in vitro. [2-(4-Phenylbutyl)phenoxy]alkylamines showed strong inhibition of both 5-HT2 and D2 receptors. It particular, [2-(4-phenylbutyl)phenoxy]-methylpiperidine derivatives, 10b, 10i and 10q, exhbited potent inhibition. The structure-activity relationships in this series of compounds are discussed.View full abstractDownload PDF (1169K) -
Masayuki YOSHIKAWA, Toshiyuki MURAKAMI, Kenichi YASHIRO, Johji YAMAHAR ...1998 Volume 46 Issue 4 Pages 647-654
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe methanolic extract and 1-butanol-soluble fraction of American ginseng, the roots of Panax quinquefolium L., were found to exhibit a protective effect on liver injury induced by D-galactosamine and lipopolysaccharide. Five new dammarane-type triterpene oligoglycosides called quinquenosides I, II, III, IV, and V were isolated together with fourteen known dammarane-type triterpene oligoglycosides such as chikusetsusaponin IVa, pseudo-ginsenoside-RC1, malonyl-ginsenoside-Rb1, and notoginsenosides-A, -C, and -K from the 1-butanol-soluble fraction. From the ethyl acetate-soluble fraction, four known acetylenic compounds and 6'-O-acetyl ginsenoside-Rg1 were isolated. The structures of quinquenosides I, II, III, IV, and V were determined on the basis of chemical and physicochemical evidence as 3-O-[6-O-(E)-2-butenoyl-β-D-glucopyranosyl(1→2)-β-D-glucopyranosyl]-20-O-(β-D-glucopyranosyl) 20(S)-protopanaxadiol (quinquenoside I), 3-O-[6-O-(E)-2-octenoyl-β-D-glucopyranosyl(1→2)-β-D-glucopyranosyl]-20-O-[β-D-glucopyranosyl(1→6)-β-D-glucopyranosyl]20(S)-protopanaxadiol (quinquenoside II), 3-O-[β-D-glucopyranosyl(1→2)-6-O-acetyl-β-D-glucopyranosyl]-20-O-(β-D-glucopyranosyl) 20(S)-protopanaxadiol (quinquenoside III), 3-O-[β-D-glucopyranosyl(1→2)-β-D-glucopyranosyl]-20-O-[β-D-glucopyranosyl(1→6)-β-D-glucopyranosyl]-3β, 7β, 20(S)-trihydroxydammar-5, 24-diene (quinoquenoside IV), and 3-O-[β-D-glucopyranosyl(1→2)-β-D-glucopyranosyl]-20-O-[α-D-glucopyranosyl(1→4)-β-D-glucopyranosyl(1→6)-β-D-glucopyranosyl]20(S)-protopanaxadiol (quinquenoside V).View full abstractDownload PDF (1143K) -
Emi OKUYAMA, Shigeru FUJIMORI, Mikio YAMAZAKI, Takeshi DEYAMA1998 Volume 46 Issue 4 Pages 655-662
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe extract of Viticis Fructus appeared to have an analgesic effect, and was subjected to activity-guided separation using acetic acid-induced writhing in mice. The active fraction gave new compounds, vitexfolin A (1A), B and C, 10-O-vanilloylaucubin (3), dihydrodehydrodiconiferylalcohol-β-D-(2'-O-p-hydroxybenzoyl)glucoside (4), and vanilloyl-β-D-(2'-O-p-hydroxybenzoyl)glucoside, together with agnuside (2) and eryhro- and threo-guaiacylglycerols. Compounds 1A and 2-4 showed significant writhing inhibition following oral administration at doses of 15, 50, 25, and 50 mg/kg, respectively The effect on pressure pain threshold was tested using compounds 1A and 2 at a dose of 50 mg/kg, and only the former produced the analgesia. The analgesic effect of some related iridoid glucosides is also discussed.View full abstractDownload PDF (1035K) -
Masayoshi OHYAMA, Toshiyuki TANAKA, Munekazu IINUMA, Charles L. BURAND ...1998 Volume 46 Issue 4 Pages 663-668
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new prenylated flavanone glucoside (sophoraflavanone I 7-O-β-glucopyranoside) and three new resveratrol oligomers, stenopyllols A-C, were isolated from the roots of Sophora (S.) stenophylla along with six known flavonoids and three known resveratrol oligomers. Their structures were determined by spectroscopic analysis of correlation spectroscopy involving long-range coupling and nuclear Overhouser effect experiments.View full abstractDownload PDF (777K) -
Shin-ichi KONDO, Shouichi HOSAKA, Masayuki KUZUYA1998 Volume 46 Issue 4 Pages 669-673
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWe carried out the mechanochemical polymerization of methacryloyl derivatives of acetoaminophen and 5-fluorouracil in the presence of lactose. The reaction proceeded readily and the polymeric prodrugs were quantitatively prodruced. This method produces powdered polymeric produgs in which fine particles of lactose are homogeneously dispersed, sicne the reaction proceeds quantitatively through a totally dry process. It is difficult to prepare such a powdered polymeric prodrug by conventional solution polymerization.The rate of drug release of polymeric prodrugs increases with increasing content of lactose, as is shown to be true of the specific surface of polymeric prodrugs. These results suggest that lactose is homogeneously dispersed in powdered polymeric prodrugs.The present method seems applicable to a wide variety of pharmaceutical aids. If one takes the physicochemical property of pharmaceutical aids into consideration, novel polymeric prodrugs with a variety of drug release rates can be synthesized simultaneously with mixing.View full abstractDownload PDF (728K) -
Yasushi ARAKAWA, Takahiro GOTO, Kazuya KAWASE, Shigeyuki YOSHIFUJI1998 Volume 46 Issue 4 Pages 674-680
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe hetero Diels-Alder adducts 6a-d derived from azodibenzoyl and cyclic dienes were oxidized by ruthenium tetroxide and transformed into meso-diaminodicarboxylic acids 12a-d via the new cyclic hydrazoacetic acids 9a-d.View full abstractDownload PDF (1240K) -
Hideko INOUE, Mari WATANABE, Hirokazu NAKAYAMA, Mitsutomo TSUHAKO1998 Volume 46 Issue 4 Pages 681-683
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe stereoselective phosphorylation of D-glucopyranose has been achieved using inorganic sodium cyclo-triphosphate hexahydrate (P3m), Na3P3O9·6H2O. The reaction product has been confirmed to the β-D-glucopyranosyl 1-triphosphate by multinuclear NMR and HPLC, and its maximum yield was about 47%.View full abstractDownload PDF (507K) -
Keisuke OHTA, Yoshiyuki MIZUSHIMA, Noriko HIRATA, Masaharu TAKEMURA, F ...1998 Volume 46 Issue 4 Pages 684-686
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new sulfolipid, KM043, which belongs to the 6-sulfo-α-D-quinovopyranosyl-(1→3')-1', 2'-diacylglycerol (SQDG) class of compounds, has been isolated from a marine red alga, Gigartina tenella, as a potent inhibitor of eukaryotic DNA polymerases and HIV-reverse transcriptase type 1. Its structure was determined on the basis of spectroscopic and gas chromatographic analyses. The inhibition was dose-dependent, and complete (more than 90%)inhibition of DNA polymerase α (pol. α), DNA polymerase β (pol. β) and HIV-reverse transcriptase type 1 (HIV-RT) was observed at concentrations of 5, 10, and 30 μM, respectively.View full abstractDownload PDF (495K) -
Carmen BALO, Franco FERNANDEZ, Evangelina LENS, Carmen LOPEZ1998 Volume 46 Issue 4 Pages 687-689
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA carbocyclic analogue of uridine, (±)-1-[t-2, t-3-dihydroxy-c-4-(hydroxymethyl)-r-1-cyclopentylmethyl]-1, 2, 3, 4-tetrahydropyrimidine-2, 4-dione (13), was synthesized with a view to studying its structure-activity relationships.View full abstractDownload PDF (598K) -
Takashi ISHIZU, Masako FUJIWARA, Akira YAGI, Shunsaku NOGUCHI1998 Volume 46 Issue 4 Pages 690-692
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe ginseng tetrapeptide H-L-Val-γ-D-Glu-D-Arg-Gly-OH (1) was synthesized using a solution-phase methodology, and its solution conformation in dimethyl sulfoxide (DMSO)-d6 was determiend by a combination of NMR and computational techniques with the DADAS90 program. This compound has a rigid backbone based on three intramolecular hydrogen bonds between D-Arg NH and L-VAL CO, between Gly NH and D-Glu CO, and between Gly NH and Gly CO.View full abstractDownload PDF (520K) -
Yuko TAKEMURA, Masako WADA, Motoharu JU-ICHI, Chihiro ITO, Hiroshi FUR ...1998 Volume 46 Issue 4 Pages 693-696
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new bisacridone alkaloid, named bis-5-hydroxynoracryonycine, was isolated from the roots of Citrus paradisi MACF. On the basis of spectroscopic analysis and synthesis, the structure was elucidated as a dimer of 5-hydroxynoracronycine.View full abstractDownload PDF (548K) -
Akira ASAGARASU, Taketo UCHIYAMA, Kazuo ACHIWA1998 Volume 46 Issue 4 Pages 697-703
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSome HIV-protease inhibitor derivatives having an N-carbomethoxycarbonyl-prolyl-phenylalanine benzyl ester (CPF) moiety as a binding site to gp120 were designed and synthesized. Almost all the compounds bearing CPF on the phenoxyacetyl group showed protease-inhibitory activity. Compounds 25a and 25b, which have the CPF moiety at the ortho- and meta-positions of the phenoxyacetyl group, respectively, had anti-HIV activity, although the others showed only protease-inhibitory activity. These results suggest that 25b binds to gp120 and inhibits HIV protease.View full abstractDownload PDF (1109K) -
Manabu HIRAOKA, Atsuko NISHIKAWA, Toshiaki MORIMOTO, Kazuo ACHIWA1998 Volume 46 Issue 4 Pages 704-706
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSNovel chiral P, S-hybrid ligands bearing 1, 2-cis phosphinomethyl (or thiomethyl) and thio (or phosphino) groups on a cyclopentane skeleton were prepared by using borane as a protecting group for the phosphino group. Asymmetric hydrosilylation of acetophenone with 1 mol% of rhodium complex catalysts prepared in situ from [Rh(COD)Cl]2 and P, S ligands, (1R, 2R)-2-(diphenylphosphino)methyl-1-(phenylthio)cyclopentane (TPCP) and (1R, 2S)-1-diphenylphosphino-2-[(phenylthio)methyl]cyclopentane (PTCP) gave the corresponding alcohols. The asymmetric hydrosilylation with the ligand TPCP showed higher enantioselectivity than that with PTCP or a diphosphine ligand (1R, 2R)-1-(diphenylphosphino)-2-[(diphenylphosphino)methyl]cylopentane (PPCP).View full abstractDownload PDF (513K) -
Laurence SALMON, Valerie LANDRY, Oleg MELNYK, Louis MAES, Christian SE ...1998 Volume 46 Issue 4 Pages 707-710
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA simplified approach to the synthesis of 2-polyamine linked-monoindolylmaleimides has been achieved, leading to a new series of trypanothione reductase inhibitors. The conditions of access to N, 2-bis(polyamine)-3-monoindolylmaleimides and N, N'-bis(monoindolylmaleimide) polyamines are described. Measured inhibitory activities towards trypanothione reductase from Tryanosoma cruzi show the importance of both aromatic moieties and polyamine chains for trypanothione reductase recognition.View full abstractDownload PDF (728K) -
Jean GUILLON, Veronique LELONG, Olivier RENAULT, Michel BOULOUARD, Pat ...1998 Volume 46 Issue 4 Pages 711-714
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSVarious 4-alkoxyphenylimidazolidin-2-ones were prepared from benzaldehydes via a Curtius rearrangement and were evaluated for their anticonvulsant activities.View full abstractDownload PDF (582K) -
Nanda NAGAPPA, Tanu MIMANI, Begur SHESHADRI, Sanabaghatta Mayanna Gowd ...1998 Volume 46 Issue 4 Pages 715-717
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSCyclic voltammetry of diazepam has been investigated in acid solution (pH 1.0) on a glassy carbon electrode.A well defined cathodic peak is observed. The interferences by the solution components on the estimation are studied. A simple, accurate, sensitive and rapid method for the determination of the drug in pharmaceutical formulations is proposed.View full abstractDownload PDF (489K) -
Takeshi CHIYODA, Katsumi IIDA, Kazuhiro TAKATORI, Masahiro KAJIWARA1998 Volume 46 Issue 4 Pages 718-720
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSUrease inhibitors are candidate drugs to treat infection with the human pathogen, Helicobacter pylori, which produces a potent urease [urea amidohydrolase; EC 3.5.1.5]. We developed a screening system based on 13C-NMR measurement of the time course of decrease in the signal of 13C-urea in the presence of urease. The effect on urease activity of known inhibitors, hydroxamic acids, L-ascorbic acid, 2, 2'-dipyridyl disulfide and ninhydrin, was speedily and conveniently measured by this method.View full abstractDownload PDF (523K) -
Tenji KONISHI, Takao KONOSHIMA, Yasuhiro FUJIWARA, Shiu KIYOSAWA1998 Volume 46 Issue 4 Pages 721-722
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA novel seco-labdane-type diterpene, excoecarin H was isolated from resinous wood of Excoecaria aggallocha collected from Okinawa prefecture. Stereochemistry of the new diterpene was determined on the basis of chemical and physicochemical evidence.View full abstractDownload PDF (431K) -
Chieko TANI, Yukio OGIHARA, Tadahiro TAKEDA1998 Volume 46 Issue 4 Pages 723-725
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThree new triterpenoidal saponins were isolated from the branches of Calliandra anomala (KUNTH) MACBR. On elucidation of their structures, we noticed correlations between a series of structures and their HPLC retention time. By this behavior and the FAB-MS spectrum, the structures of three saponins (calliandra saponin M, N and O) were established.View full abstractDownload PDF (462K) -
Iclal SARACOGLU, Keisuke KOJIMA, U. Sebnem HARPUT, Yukio OGIHARA1998 Volume 46 Issue 4 Pages 726-727
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThree known phenylethanoid glycosides, forsythoside B, alyssonoside and leucosceptoside B, and a known iridoid glycoside, lamiide, were isolated from the methanol extract of the aerial parts of Phlomis pungens WILLD. var. pungens (Labiatae) along with one new phenylethanoid glycoside, (4-hydroxyphenyl)ethyl (5-O-syringly-β-D-apiofuranosyl)-(1→2)-β-D-glucopyranoside, termed hattushoside.View full abstractDownload PDF (384K) -
Kaoru KANEKO, Ken KANADA, Masaharu MIYAGI, Noriyasu SAITO, Tetsuya OZE ...1998 Volume 46 Issue 4 Pages 728-729
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSodium alginate (ALNa) of a natural polysaccharide is known to form a water-insoluble gel when combined with a bivalent metal. In this study, we prepared tablets containing ALNa and calcium gluconate (GLCa) as a bivalent metal, and studied the application of the water-insoluble gel involving the controlled release of a test drug by permeation of water. Dry-coated tablets containing theophylline (TP) as a model drug, ALNa and GLCa were prepared by the dry powder compression method.The controlled release of TP was evaluated by the dissolution test according to JP XIII. The release rate was extremely high for the tablets which contained only TP and GLCa. A zero order or sigmoidal release profile was observed for the tablets that contained only TP and ALNa. On the other hand, the lowest dissolution rate and a sigmodidal release profile were observed for the tablet containing TP and GLCa in its core and ALNa in its outer phase. These results suggest that dry-coated tablets containing ALNa and GLCa and prepared by the direct powder compression method would be useful for the controlled release of drugs.View full abstractDownload PDF (456K) -
Hiroshi YAMASHITA, Kazuo MASUDA, Hiroyuki AGETA, Kenji SHIOJIMA1998 Volume 46 Issue 4 Pages 730-732
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSCyclohopenol (1) and cyclohopanediol (2), two hexacyclic hopane derivatives, were isolated along with hop-22(29)-en-28-al (3) from the rhizomes of Pyrrosia lingua. They were characterized as (28S)-28, 29-cyclohop-22(30)-en-28-ol and (22R, 28S)-28, 29-cyclohopane-22, 28-diol, respectively, on the basis of spectral analyses.View full abstractDownload PDF (494K) -
Noriko SHIBATA, Etsuko ITOH, Shiro TERASHIMA1998 Volume 46 Issue 4 Pages 733-735
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSynthesis of (2S, 3S)-3-amino-2-hydroxy-4-phenylbutyric acid was achieved by the highly diastereoselective cyanohydrin formation of (S)-2-N, N-dibenzylamino-3-phenylpropanal with acetone cyanohydrin in the presence of trimethyl-aluminum as a key step.View full abstractDownload PDF (478K) -
Manabu NODE, Mamoru ARAKI, Hiroaki TANAKA, Daisaku NAKAMURA, Takehisa ...1998 Volume 46 Issue 4 Pages 736-738
Published: April 15, 1998
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe first asymmetric synthesis of (-)-isoiridomyrmecin and formal synthesis of (-)-loganin were done using chiral C2-symmetric building block dimethyl 3, 7-dihydroxy-cis-bicyclo[3.3.0]octa-2, 6-diene-2, 6-dicarboxylate (2) which was prepared by the lipase-catalyzed asymmetric demethoxy-carbonylation of tetramethyl 3, 7-dioxo-cis-bicyclo-[3.3.0]octane-2, 4, 6, 8-tetracarboxyrate (1).View full abstractDownload PDF (480K)
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