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Volume 47, Issue 7
Displaying 1-33 of 33 articles from this issue
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Morihiro KANNO, Takeshi SHIBANO, Michio TAKIDO, Susumu KITANAKA1999 Volume 47 Issue 7 Pages 915-918
Published: July 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo new anti-allergic compounds, torososide B and torosachrysone 8-O-6"-malonyl gentiobioside were isolated from the seeds of Cassia torosa CAV., and their structures were established as physcion 8-O-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl-(1→3)-β-D-glucopyranosyl-(1→6)-β-D-glucopyranoside and torosachrysone 8-O-β-D-glucopyranosyl-(1→6)-6-malonyl β-D-glucopyranoside on the basis of spectral and chemical evidence.Torososide B and torosachrysone 8-O-6"-malonyl gentiobioside were found to inhibit the release of leucotrienes from rat peritoneal mast cells induced by calcium ionophore A 23187.View full abstractDownload PDF (584K) -
Kiminori KAWAKAMI, Masahiro YASUDA, Kazuhiro ISHII, Yoshio KOKUSENYA, ...1999 Volume 47 Issue 7 Pages 919-922
Published: July 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTo define the mechanism of the protection by ecabet sodium of the gastric mucosa, the characteristics of protein binding of this drug were investigated using a quartz-crystal microbalance (QCM) method. The binding rate constants (kb) and the binding amounts (Δm) were obtained from time courses of the frequency decrease (mass increase) of the QCM. The binding constants to proteins of two ecabet analogues (G1, ecabet type and G2, non-ionic ecabet type) were dependent on the pH, leading to large kb values at the acidic region. Furthermore, the kb values of G1 with the addition of bovine serum albumin (BSA) and bovine serum fibrinogen (BSF) at the acid region were larger than those of G2. The difference in kb values between G1 and G2 for porcine gastric mucin (PGM) is hardly discernible. Ecabet seems to be more heavily distributed in the ulcerous areas than in the intact mucosa, judging from the large binding constants of this drug to BSA and BSF compared with those to PGM. It is suggested that ecabet is bound to proteins by hydrophobic interaction, moreover, the electrostatic interaction between this drug and proteins (BSA and BSF) occurs at acidic pH region. On account of these interactions, ecabet sodium seems to have a more protective effect on an ulcer at intraluminal acidity than sucralfate. Finally, QCM was found to be a useful technique for detecting quantitatively the time course of binding proteins with drug.View full abstractDownload PDF (635K) -
Yoshiko NAGATA, Chie MIYAMOTO, Yoshikazu MATSUSHIMA, Shigenobu MATSUMO ...1999 Volume 47 Issue 7 Pages 923-927
Published: July 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAn aqueous solution of d-α-tocopherol solubilized with sodium deoxycholate became colored on standing, probably due to air oxidation. 5-Formyl-7, 8-dimethyltocol (1) and 7-formyl-5, 8-dimethyltocol (2) were isolated from the solution and concluded to be responsible for the coloration. In oxidation of aqueous solutions of d-α-to-copherol, the time course of formation of products was followed by analytical HPLC. The main oxidation product was 1 in solutions solubilized with sodium deoxycholate and sodium cholate, whereas α-tocoquinone was the main product in those solubilized with 2, 6-di-O-methyl-β-cyclodextrin.View full abstractDownload PDF (671K) -
Takeshi SHIOTA, Teruo YAMAMORI, Katsunori SAKAI, Mitsugu KIYOKAWA, Tsu ...1999 Volume 47 Issue 7 Pages 928-938
Published: July 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWe have already reported 7-oxo-4, 7-dihydropyrazolo[1, 5-α]pyrimidine-3-carboxylic acid derivatives, which are potent in vitro angiotensin II (AII) antagonists, but have no oral antihypertensive activity. Removal of the carboxylic acid and replacement of the heteroaromatic system afforded potent in vitro antagonists. Removal of the carbonyl oxygen and changing the position of the biphenyltetrazole substituent were critical to the display of oral activity. To improve the in vitro and oral activities, modifications were made of the substitutents at the 3- and 5- positions of the pyrazolo[1, 5-α]pyrimidine. Structure-activity studies showed the methyl substituent at the 3-position to be essential for potent in vivo activity. We present the design, syntheses, and biological data of a series of pyrazolo[1, 5-α]pyrimidine derivatives, which are orally active AII receptor antagonists.View full abstractDownload PDF (1527K) -
Paul Wan Sia HENG, Lai Wah CHAN, Siok Hui CHEW1999 Volume 47 Issue 7 Pages 939-943
Published: July 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIn the formation of a coated controlled release preparation with functional coat layers, hydroxypropylmethylcellulose was used to form a diffusion layer which swelled immediately upon wetting. Eudragit RS30D was used to form the outer retention layer. The repture of pellet coat occurred when the Eudragit RS30D was unable to withstand the expansion in volume due to the influx of water and swelling of the hydroxypropylmethylcellulose diffusion layer. The sucrose core was able to contribute an osmotic effect. The hydrostatic pressure built up within the pellet can cause the pellet coat to rupture. Sodium chloride deposited in the diffusion coat was able to delay the dursting of the pellet coat. This was due to the competition for the imbibed water between sodium chloride and hydroxypropylmethylcellulose.The rupture of the pellet coat did not result in a total failure of the controlled drug delivery mechanism. Similar drug release rates were obtained irrespective whether there was a puncture in the pellet coat or not. Pressure bulit-up in the region away from the puncture pushed the core material towards the point of puncture and sealed the puncture point. In addition, the swelling of polymer around the point of rupture ensured continuity in the drug diffusion barrier.View full abstractDownload PDF (862K) -
Nagwa NAWAR, Nasser Mohamed HOSNY1999 Volume 47 Issue 7 Pages 944-949
Published: July 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSCoordination compounds of some transition metal ions with 2-acetylpyridene-o-hydroxybenzoylhydrazone (APo-OHBH) were synthesized. Their structures have been characterised by elemental analyses, electrical conductance, magnetic moments (at 25°C) and spectral (IR, UV, NMR) studies. The fast atom bombardment (FAB) method was used for obtaining mass spectra of the positive ion FAB studies of the ligand and some metal complexes. The thermal behaviour of selected complexes was investigated by thermal gravimetrical analysis (TGA) and differential thermal analysis (DTA) techniques. The IR spectra show that the ligand acts in a neutral bidentate, neutral tridentate and/or mononegative tridentate fashion depending on the metal salt used and the medium of the reaction. Preliminary pharmacological tests on the ligand and its complexes showed some antimicrobial activity.View full abstractDownload PDF (930K) -
Nadia PELLEGRINI, Bernard REFOUVELET, Gregorio CRINI, Olivier BLACQUE, ...1999 Volume 47 Issue 7 Pages 950-955
Published: July 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSNew dipeptides, structural analogues of known immunomodulating agents, were prepared by stereospecific condensation between 2-substituted thiazolidine-4-carboxylate esters with N-substituted L-proline or L-thiaproline. The structure of these compounds has been elucidated by combination of NMR methods and X-ray analysis. In addition, NMR measurements on dipeptides indicated the presence of S-cis and S-trans conformers around the amide bonds.View full abstractDownload PDF (870K) -
Tetsuo IWAMA, Shin-ichiro TSUJIYAMA, Hironori KINOSHITA, Kiyoko KANEMA ...1999 Volume 47 Issue 7 Pages 956-961
Published: July 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSChiral hydroxy chalcogenides in the presence of TiCl4 achieved the asymmetric version of the chalcogeno-Baylis-Hillman reaction. The reaction proceeded under atmospheric pressure for 1h. 10-Methylthioisoborneol (9) achieved the best enantioselectivity. A methoxy derivative 10 of 10-methylthioisoborneol resulted in lower-selectivity than that obtained by 10-methylthioisoborneol (9). A hydroxyl group is required to perform good asymmetric induction. The asymmetric chalcogeno-Baylis-Hillman reaction with a C2 symmetric bidentate ligand-TiCl4 complex was also examined. Diol ligands gave the adduct in low to good yields with low or no enantiomeric excess. The adduct was also obtained in low to high yields with low or no enantiomeric excess using bisoxazoline ligands.View full abstractDownload PDF (910K) -
Hideaki OTSUKA1999 Volume 47 Issue 7 Pages 962-965
Published: July 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFrom the aerial parts of Tripterospermum japonicum, five new xanthone glycosides, named triptexanthosides A-E, were isolated along with a known xanthone C-glucoside, mangiferin. Their structures were elucidated as 1, 2, 6, 8-tetrahydroxyxanthone (norswetianin) 1-O-β-D-glucopyranoside and 1-O-β-gentiobioside, and 1, 2, 8-trihydroxy-5, 6-dimethoxyxanthone 2-O-β-D-glucopyranoside, 2-O-β-primeveroside and 1-O-gentiobioside, respectively, from spectroscopic evidence and acid hydrolysis.View full abstractDownload PDF (644K) -
Tokumi MARUYAMA, Satoshi TAKAMATSU, Shigetada KOZAI, Yoshiko SATOH, Ku ...1999 Volume 47 Issue 7 Pages 966-970
Published: July 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA facile and practicam method to infroduce fluorine at the up-side of the 2'-carbon of nucleosides is described. 6-Chloropurine riboside 3 was converted to the 3'-O-benzoate 4a via a stannylene complex, then converted to the 3'-O-benzoyl-5'-O-tritylriboside 5a. In the presence of pyridine, migration of the 3'-benzoyl groups of 4a and 5a to 2'-OH was rather slow. Hence, 5a was reacted with diethylaminosulfur trifluoride (DAST) in CH2Cl2 in the presence of pyridine to give the 2'-deoxy-2'-fluoroarabinoside 6 in good yield. The 3'-O-benzoyl-5'-O-trityl protecting system was easy to deprotect selectively. Thus, treatment of 6 with ammonia in MeOH gave the 5'-O-trityl compound 7, which was subjected to esterificaiton with phenyl chlorothionoformate, radical deoxygenation with tris(trimethylsilyl)silane and acid treatment to afford 9-(2, 3-dideoxy-2-fluoro-β-D-threo-pento-furanosyl)adenine(FddA) 2. In addition, acid treatment of 7 gave 9-(2-deoxy-2-fluoro-β-D-arabinofuranosyl)adenine (FdaraA) 1.View full abstractDownload PDF (765K) -
Yuzo MATSUMOTO, Ryuji TSUZUKI, Akira MATSUHISA, Noriyuki MASUDA, Yoko ...1999 Volume 47 Issue 7 Pages 971-979
Published: July 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThree new series of analogues related to 3, 4-dihydro-2H-1, 4-benzoxazine derivative 1a were synthesized and evaluated for their potassium channel activating activity. In the first series I, where the 6, 7-positions were disubstituted, it was found that an electron-withdrawing substituent was preferable at the 6 position, bet either an electron-withdrawing or releasing substituent without bulkiness was tolerated at the 7 position. In the second series II, where several heterocycles were introduced into the 6, 7-positions, the oxadiazole derivative 6 showed more potent activity than cromakalin. In the third series III, where the benzene ring was replaced by pyridine ring, borane complex 16 had equivalent activity to cromakalim. Especially, compound 6 showed a potent hypotensive effect with a long duration of action in the spontaneous hypertensive rat and had a lesser increasing effect on intracranial pressure in dogs than 1a and levcromakalim, showing a good profile as a antihypertensive agent.View full abstractDownload PDF (1253K) -
Satoshi SUWA, Takeshi SAKAMOTO, Yasuo KIKUGAWA1999 Volume 47 Issue 7 Pages 980-982
Published: July 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSN-Phenylthiophthalimide reacts with AlCl3 or TiCl4 in areanes to give phenylthiated arenes alone via a phenylsulfenium ion intermediate, modified neglect of diatomic overlap (MNDO) molecular orbital calculations of which revealed that the positive charge preferentially populates the sulfur atom rather than the phenyl group in the phenylsulfenium ion.View full abstractDownload PDF (477K) -
Masaszumi IKEDA, Serry A.A. EL BIALY, Ken-ichi HIROSE, Miho KOTAKE, Ta ...1999 Volume 47 Issue 7 Pages 983-987
Published: July 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA formal total synthesis of (-)-cephalotaxine (1) has been achieved. The key step is an intramolecular aldol condensation of the diketone 9, which in turn was obtained in three steps from the azabicyclic compound 6 derived from D-proline according to Seebach's procedure. Treatment of 9 with a catalytic amount of sodium 2-methyl-2-butanolate in benzone at room temperature gave the α, β-unsaturated ketone 8 in 43% yield. Catalytic hydrogenation of 8 followed by reduction of the ketone 22 with sodium borohydride and acetylation of the resulting alcohol 23 gave the acetoxy derivative 24, which, after deprotection, was acylated with (methylthio)acetic acid to give the amide 26. Compound 26 was converted into optically active ketolactam 4 folowing the synthetic operations developed for the synthesis of the racemic compound.View full abstractDownload PDF (877K) -
Junichi KITAJIMA, Toru ISHIKAWA, Tasuko TANAKA, Yoshiteru IDA1999 Volume 47 Issue 7 Pages 988-992
Published: July 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFrom the water-soluble portion of the methanolic extract of fennel, seven new sugar alcohols (two deoxybutitols, four deoxypentitols and one deoxyhexitol) and a sugar lactone were isolated, together with seven known glucides, four nucleosides, (3R)-2-hydroxymethylbutane-1, 2, 3, 4-tetrol and uracil. From the results of spectral investigation, the new compounds were characterized as 1-deoxythreitol (9), (2R)-butane-1, 2, 4-triol (10), 1-deoxy-D-ribitol (11), 1-deoxy-D-xylitol (12), 2-deoxy-D-ribitol (13), 3-deoxyarabinitol (14), 1-deoxy-D-glucitol (16) and 2-deoxy-D-ribono-1, 4-lactone (15), respectively.View full abstractDownload PDF (723K) -
Atsuo BABA, Akira MORI, Tsuneo YASUMA, Satoko UNNO, Haruhiko MAKINO, T ...1999 Volume 47 Issue 7 Pages 993-999
Published: July 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe syntheses and anti-inflammatory activities of novel thieno[2, 3-b]pyridine and thieno[2, 3-b : 5, 4-c']-dipyridine derivatives are desrcibed. These compounds were designed by modification of the quinoline template of a new type of disease-modifying antirheumatic drug (DMARD), TAK-603, and prepared by the Friedlander reaction as a key reaciton. Their anti-inflammatory effects were evaluated using an adjuvant arthritis rat model. Most of the compounds which included a dithylamino moiety in the side chain had potent anti-inflammatory effect. In particular, ethyl 2-(diethylaminomethyl)-4-(3, 4-dimethoxyphenyl)thieno[2, 3-b : 5, 4-c']dipyridine-3-carboxylate (21) exhibitied more potent activity than TAK-603.View full abstractDownload PDF (1028K) -
Akira OGAWA, Satoshi SHUTO, Motohiro TANAKA, Takuma SASAKI, Shuji MORI ...1999 Volume 47 Issue 7 Pages 1000-1005
Published: July 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSPyrimidine carbocyclic nucleosides with a hydroxyamino group instead of a hydroxymethyl group at the 4'-position of the sugar moiety were designed as potential antitumor and/or antiviral agents. Pd(O)-catalyzed reactions of enantiomerically pure (+)-(1R, 4S)-4-[(tert-butyldiphenylsilyl)oxy]-1-(ethoxycarbonyloxy)-2-cyclopentene (9) with N3-benzoylthymine and -uracil gave carbocyclic nucleosides 10 and 11. Subsequent Pd (O)-catalyzed reactions of N3-benzoyl-1-[(1R, 4S)-4-(ethoxycarbonyloxy)-2-cyclopenten-1-yl]thymne (14) and -uracil (15) with O-benzylhydroxylamine smoothly gave the hydroxyamino-substituted carbocyclic nuclesides 16 and 17. From these nucleosides, the target compounds were prepared after deprotection or further reactions. The 2', 3'-didehydro-2', 3'-dideoxythymidine (D4T) analogue 20 was the most effective compound, with IC50 values of 27.3 and 34.5μM against KB and L1210 cells in vitor. Carbocyclic analogues of uridine and cytidine (29 and 32) were less effective than 20 against both cell lines.View full abstractDownload PDF (987K) -
Franco FERNANDEZ, Xerardo GARCIA-MERA, Gonzalo RODRIGUEZ, Anahi URRUTI ...1999 Volume 47 Issue 7 Pages 1006-1009
Published: July 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIn a search for novel atypical antipsychotics, the synthesis of new hyxahydrocarbazoles and spiro indoles N-substituted with a 3-(dimethylamino)propyl chain is descrived, together with the results of an in vitro evaluation of their affinities for D2 and 5-HT2A receptors.View full abstractDownload PDF (787K) -
Kuniharu SUZUMURA, Mikiko YASUHARA, Keiko TANAKA, Akio ODAWARA, Hirosh ...1999 Volume 47 Issue 7 Pages 1010-1012
Published: July 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWe investigated the in vitro hydroxyl radical scavengig activity of fluvastatin, a 3-hydroxy-3-methylglutaryl (HMG)-CoA reductase inhibitor. Fluvastain showed hydroxyl redical scavenging activity as potent as that of dimethylthiourea and α-tocopherol, which are well-known respectively, as a hydroxyl radical scavenger and a natural antioxidant. Since this effect was not observed in other HMG-CoA reductase inhibitors, such as pravastain and simvastatin, the scavenging effect of fluvastatin on hydroxyl radicals would not be a common property of HMG-CoA reductase inhibitors, but is derived from the unique chemical structure of fluvastatin. The hydroxyl radical scavenging activities of human metabolites of fluvastatin were also determined. All the tested metabolites possessing the fluorophenyl indole moiety showed activity. Among them, the metabolites which possess a phenolic hydroxyl group on the indole moiety showed stronger effects than that of fluvastatin. We suggest that the fluorophenyl indole moiety of fluvastatin is important for manifestation of the activity and that the phenolic hydroxyl group enhances the potency.View full abstractDownload PDF (551K) -
Synthesis of Alkynyl- and Aryldifluoroacetate Using a Copper Complex from Ethyl BromodifluoroacetateKazuyuki SATO, Ryuichi KAWATA, Fumitaka AMA, Masaaki OMOTE, Akira ANDO ...1999 Volume 47 Issue 7 Pages 1013-1016
Published: July 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSEthyl bromodifluoroacetate reacted with alkenyl or aryl iodides in the presence of copper powder in dimethyl sulfoxide (DMSO) to give the corresponding alkynyl- or aryldiffuoroacetates in moderated to good yields.View full abstractDownload PDF (605K) -
Yueh-Hsiung KUO, Ming-Tsang YU1999 Volume 47 Issue 7 Pages 1017-1019
Published: July 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFour new sesquiterpenes, cis-4, 5-dihydroxycorocalane (1), trans-4, 5-dihydroxycorocalane (2), calamenen-10α-ol (3), and 15-hydroxycadalene (4) together with two know compounds, calamenen-10β-ol (5) and cadalene (6) were isolated from the heartwood of Juniperus formosana HAY. var. concolor HAY.View full abstractDownload PDF (482K) -
Takuya MAEDA, Yuki MANABE, Masashi YAMAMOTO, Munehiro YOSHIDA, Kiyo OK ...1999 Volume 47 Issue 7 Pages 1020-1023
Published: July 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSPotent new biocides against both bacteria and fungi, 4, 4'-(1, 6-hexamethylenedioxydicarbonyl)bis(1-alkylpyridinium iodide)s (4DOCBP-6, n) (alkyl chain length, n=8, 10, 12, 14, 16 and 18) were synthesized. 4DOCBP-6, n is bis-quaternary ammonium compound (bis-QAC) and has a symmetrical dimeric structure which is composed of two alkylpyridinium iodides connected with a hexamethylenedioxydicarbonyl chain. 4DOCBP-6, 10 and 4DOCBP-6, 12 exhibited wide and effective antimicrobial spectra, compared with those of typical bactericides, N-dodecylpyridinium iodides (P-12) and benzyldimethyldodecylammonium chloride (BAC), or a popularly-used fungicide, 2-(4-thiazolyl)benzimidazole (TBZ). Their superior properties would be due to the unique dimeric structure which contains two active moieties in a molecule.View full abstractDownload PDF (639K) -
Thirumala R. KOMMURU, Mohammad ASHRAF, Mansoor A. KHAN, Indra K. REDDY1999 Volume 47 Issue 7 Pages 1024-1028
Published: July 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSCoenzyme Q10 (CoQ10), a highly lipophilic compound present in the inner mitochondrial membrane, is essential for production of celllar energy in the form of ATP. CoQ10 is used as an antioxidant and also in the treatment of various cardiovascular disorders. The relative bioavaliabilities of powder filled capsule (I) and oil-based formulation (II) of CoQ10 were compared in beagle dogs in an open, randomized, multiple dose, cross-over design. Poor and slow absorption characteristics were observer for both the formulations. The AUC, Cmax, and Tmax for formulation I and II are comparable (p<0.05) where the values for formulation I are 22.84±6.3μg ml-1h, 0.51±0.11μg/m, and 6.1±2.0h whereas the values for foumulation Ii are 24.32±5.6μg ml-1h, 0.55±0.16μg/ml, and 6.6±2.3h, respectively. Stability of CoQ10 at various temperature and humidity conditions and its photostability were studied. Various antioxidants were evaluated to determine the type and amount of antioxidant(s) required to improve the stability of CoQ10. Large extent of degradation was observed at 45°Cand 55°C. The effect of humidity conditions on degradation was insignificant. Among the various antioxidants studied, mixture of ascorbic acid (5%) and EDTA (0.1%) offered better protection than phenolic antioxidants such as butylated hydroxy anisole (BHA), butylated hydroxy toluene (BHT), or propyl gallate (PG). Further, increasing concentrations of phenolic antioxidants (from 0.1 to 0.3%) accelerated the degradation.View full abstractDownload PDF (772K) -
Hee-Juhn PARK, Myung-Sun LEE, Kyung-Tae LEE, Il-Cheol SOHN, Yong-Nam H ...1999 Volume 47 Issue 7 Pages 1029-1031
Published: July 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSCytotoxic compounds, oleuropein (1) and a phenylethanoid glycoside (2) were isolated from the stem bark of Syringa velutina KOM. along with coniferylaldehyde 4-O-glucoside, syringin, ligstroside, (+)-syringaresinol 4-O-glucoside, (+)-medioresinol 4"-O-glucoside and (-)-olivil 4"-O-glucoside. Phenylethanoid glycoside (2) was identified to be 3, 4-dihydroxyphenylethyl alcohol 8-O-β-D-glucopyranoside. THis compound showed the most potent cytotoxic effect on several tumor cell lines (P-388, L-1210, SNU-5 and HL-60) among eitht compounds isolated in the present study. We suggest that the 3, 4-dihydroxyphenylethoxy moiety of this compound contributes to cytotoxicity.View full abstractDownload PDF (586K) -
Nobuo HOSOKAWA, Hiroshi NAGANAWA, Takako KASAHARA, Seiko HATTORI, Masa ...1999 Volume 47 Issue 7 Pages 1032-1034
Published: July 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFutalosine, a new nucleoside analog, was isolated from a fermentation broth of Streptomyces sp. MK359-NF1. Some chemical derivatives of futalosine were prepared. 6-O-Methylfutalosine methylester inhibited growth of HeLa-S3 cells in vitro (IC50=19.5μg/ml) in contrast to the weak activity of futalosine. 6-O-Methylfutalosine methylester at concentrations higher than 10μg/ml inhibited incorporation of 3H-TdR and 3H-UR but not 3H-Leu into the acid-soluble fractions of HeLa-S3 cells.View full abstractDownload PDF (479K) -
Takashi MICHIDA, Eriko OSAWA, Tsuneaki SAITO, Yumiko YAMAOKA1999 Volume 47 Issue 7 Pages 1035-1037
Published: July 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSDimerization of cation redicals derived from 2-cyano-2-phenylvinylamines (1) to produce diphenylmethane derivatives (Ph-CH(CN)-C6H4-C(CN)=CH-NR2R3, 2) was re-examined by the AM1 (Austin model 1) method.However, dimerization of cation radicals derived from 1 was forbidden by calculation of the total energies of the dimers. An alternative reaction mechanism for the formation of 2 was proposed. Hydrolysis of cation radical (A) derived from N, N-dimethyl-2-cyano-2-phenylvinylamine (1a) gives a cyanophenylmethyl radical (F), which attacks at 1a to give a redical (G). Following anodic oxidation of G, deprotonation gives phenyl-[4-(1-cyano-2-dimethylaminovinyl)phenyl]acetonitrile (2a) as the final product.View full abstractDownload PDF (442K) -
Junko KOYAMA, Izumi TOYOKUNI, Kiyoshi TAGAHARA1999 Volume 47 Issue 7 Pages 1038-1039
Published: July 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSynthesis of the 2-arylquinoline alkaloids, 2-phenylquinoline and dubamine, and the 2-arylquinolone alkaloids, 1-methyl-2-phenyl-4-quinolone, graveoline, reevesiamine-A, and eduline, was accomplished by the Diels-Alder reaction of 1, 2, 3-benzotriazine with enamines as a kye step.View full abstractDownload PDF (446K) -
Hideaki TSUNEMATSU, Ryuichi ISOBE, Hiroshi HANAZONO, Yasuko SOEDA, Mas ...1999 Volume 47 Issue 7 Pages 1040-1043
Published: July 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe effect of Na+ ions on the fragmentation of tertiarybutoxycarbonyl (Boc) protected prolylproline (Pro-Pro) diastereomers, Boc-Pro-Pro and Boc-D-Pro-Pro, was studied in positive-ion fast atom bombardment (FAB) and tandem mass spectrometry. The formaiton of the [M+Na]+ ion for Boc-D-Pro-Pro was more predominant than that for Boc-Pro-Pro on the addition of sodium chloride in positive-ion FAB mass spectrometry, suggesting that Boc-D-Pro-Pro has a stronger Na+ ion affinity than Boc-Pro-Pro. In the collisional-activated decomposition mass spectra of the [M+Na]+ ions, the abundance of the [M+Na-C(CH3)3+H]+ ion, which is due to the loss of a tertiarybutyl group from the [M+Na]+ ion for Boc-D-Pro-Pro, was higher than that for Bos-Pro-Pro. These results indicate that the interaction of the Na+ ion with Boc-Pro-Pro is different from that with Boc-D-Pro-Pro in the FAB condition, and these diastereomers are distinguished by the addition of a Na+ ion in FAB and tandem mass spectrometry.View full abstractDownload PDF (595K) -
Motohiko SANO, Osamu HOSOYA, Shose TAOKA, Toshinobu SEKI, Takeo KAWAGU ...1999 Volume 47 Issue 7 Pages 1044-1046
Published: July 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA cationic polymer, chitosan (CHI) is anticipated to be a potent component in several dosage forms involving transdermal drug delivery systems (TDDS). Solubility of CHI and its gelation in alcoholic aqueous solutions were investigated. Elastivity of the gel containing 3% CHI, 2% oxalic acid, as a crosslinking agent, and ethanol (EtOH) and/or 1, 3-butyleneglycol (BG) was also evaluated by a rheometer. The CHI solubility in the gel was dependent on the solubility parameters of the mixed solvent. High elasticity was observed in the CHI gel when an alcoholic solvent giving low solubility of CHI was used. A good correlation was found between the gel elasticity and the relative gel concentration (=concentraiton of CHI in gel/sulubility of CHI in gel). Since the polarity of mixed solvents also affected the thermodynamic activities of drugs and penetration enhancers, optimization of the vehicle composition for TDDS is important to assure suitable drug efficacy.View full abstractDownload PDF (571K) -
Yao-Haur KUO, Shyh-Yuan LI, Ming-Der WU, Ray-Ling HUANG, Li-Ming YANG ...1999 Volume 47 Issue 7 Pages 1047-1048
Published: July 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new C18 dibenzocyclooctadiene lignan, kadsumarin A (1) was isolated from Kadsura matsudai HAYATA and Schizandra arisanensis HAYATA.The anti-HBeAg test revealed that kadsumarin A had activity at a concentration of 40 μg/ml (=90.1μM). Its sturctural elucidation by spectral analysis was discussed in this note.View full abstractDownload PDF (411K) -
Wenzhe FAN, Yasuhiro TEZUKA, Quanbo XIONG, Masao HATTORI, Tsuneo NAMBA ...1999 Volume 47 Issue 7 Pages 1049-1050
Published: July 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFour new phenylpropanoid-substituted flavan-3-ols called apocynins A-D (1-4) have been isolated from the leaves of Apocynum venetum (Apocynaceae), together with two known phenylpropanoid-substituted flavan-3-ols, catechin-[8, 7-e]-4α-(3, 4-dihydroxyphenyl)-dihydro-2(3H)-pyranone (5) and cinchonain I1 (6), and four known flavan-3-ols, (-)-epicatechin, (+)-catechin, (-)epigallocatechin, and (+)-gallocatechin. Their structures were elucidated on the basis of spectral analysis, including 2D NMR and CD spectra. They showed hepatoprotective activity against D-galactosamine (D-GaIN)/tumor necrosis factor-α(TNF-α)-induced cell death in primary cultured mouse hepatocytes.View full abstractDownload PDF (452K) -
Yoshitomo KASHIWAGI, Kazumi UCHIYAMA, Futoshi KURASHIMA, Chikara KIKUC ...1999 Volume 47 Issue 7 Pages 1051-1052
Published: July 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA chiral nitroxyl radical, (6R, 7S, 10R)-4-oxo-2, 2, 7-trimethyl-10-isopropyl-1-azaspiro[5.5]undecane-N-oxyl, was used as catalyst in the electrooxidation reaction of (R)- and (S)-1-phenyl-ethanol. Cyclic voltammetric studies showed that the catalytic current for the oxidation of (R)-1-phenylethanol is highly enhanced as compared with a very small enhancement in the oxidation current for the (S)-isomer. The (R)-isomer can be detected selectively in a mixture of (R)- and (S)-1-phenylethanol, even in the presence of an excess amount of (S)-isomer.View full abstractDownload PDF (427K) -
Kiyoshi TANAKA, Mohammad NURUZZAMAN, Masato YOSHIDA, Naoyuki ASAKAWA, ...1999 Volume 47 Issue 7 Pages 1053-1055
Published: July 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSHighly diastereoselective Michael addition of lithium diorganocuprates to the half-ester of 1, 1'-binaphthalene-8, 8'-diol gave β-substituted esters with high enantiomeric excess after methanolysis. The optically active phenolic sesquiterpenes turmeronol A (1) and B(2) have been synthesized using this reaction as a key step.View full abstractDownload PDF (440K) -
Isao KOUNO, Asuka HIRAI, Akiko FUKUSHIGE, Zhi-Hong JIANG, Takashi TANA ...1999 Volume 47 Issue 7 Pages 1056-1057
Published: July 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA novel type of sesquiterpene lactone, called strychinilactone, has been isolated from the root of Linera strychinifolia. Its structure was determined by 2D NMR techniques and X-ray analysis.View full abstractDownload PDF (332K)
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