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Volume 44, Issue 8
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Yukinori KAWAI, Kyuichi MATSUBAYASHI, Hideo HAKUSUI1996 Volume 44 Issue 8 Pages 1425-1430
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSQuinolones are a group of potent antibacterial agents. Many reports show that oral absorption of quinolones is reduced by coadministration of metallic preparations. For better understanding of this phenomenon, we investigated the complex formations of quinolones (DU-6859a, DV-7751a, DR-3862, levofloxacin) with various metal cations by pH titrations, NMR and spectrophotometry. Several metal complexes including hydroxo species were confirmed by pH titrations. The order of stability constants among trivalent metal cations was Fe3+>Al3+, and those among devalent metal cations was Cu2+>Fe2+>Zn2+>Mg2+>Ca2+. The differences in stability constants among quinolones were not as large. Complex structures and metal complex formation equilibria in aqueous solution were proposed. Quinolones were belived to bind metal cations through carboxyl group and carbonyl group of the quinolone ring, and these equilibria show that there are two types of deprotonation reactions from metal complex : the several Fe3+ complexes and Al3+ complexes liberate protons from coordinated water molecules under acidic to neutral conditions, while the other complexes liberate protons from amine groups under neutral to alkaline conditions. Moreover, quantitative behavior of metal complex in aqueous solution has been demonstrated by simulation for the first time. The simulation especially showed that quinolones interact with Al3+ in the stomach, but with Mg2+ in the intestines when coadministered with antacid containing Al3+ and Mg2+. These results suggest that the complex formation of quinolones with metal cations is an important factor affecting absorption of the former in the gastrointestinal tract.View full abstractDownload PDF (895K) -
Yueh-Hsiung KUO, Ming-Tsang YU1996 Volume 44 Issue 8 Pages 1431-1435
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThree was diterpenes, 6β-hydroxyferruginol (1a), formosaninol (2a), and formosanin (2b), were isolated from the heartwood of Juniperus formosana HAY. var. concolor HAY. The structure of formosaninol was deduced to be a dimeric ferruginol with 6-O-7' and 7-O-6' linkages on the basis of spectroscopic analysis and chemical evidence. Formosanin was a dimethyl ether of formosaninol. 6α-Hydroxy-7-oxoferruginol can be converted to 6α- and 6β-hydroxyferruginols, 6-oxoferruginol and formosaninol by lithium aluminum hydride reduction and acidification. The structure of 6β-hydroxyferruginol isolated from Cryptomeria japonica was revised to 6α-hydroxyferruginol.View full abstractDownload PDF (680K) -
Takashi YOSHIDA, Hideyuki ITO, Tsutomu HATANO, Mari KURATA, Tsutomu NA ...1996 Volume 44 Issue 8 Pages 1436-1439
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo new hydrolyzable tannins, shephagenins A and B, were isolated along with hippophaenin A and strictinin from the leaf extract of Shepherdia argentea, which showed a remarkable inhibitory activity against human immunodeficiency virus (HIV)-1 reverse transcriptase. Their structures, having a gluconic acid core, have been elucidated on the basis of spectroscopic and chemical methods. The inhibitory effect of the leaf extract on HIV-1 reverse transcriptase was found to be due to tannins, and their activities were stronger than that of (-)-epigallocatechin gallate as a positive control.View full abstractDownload PDF (693K) -
Masayuki YOSHIKAWA, Hisashi MATSUDA, Hiroshi SHIMODA, Hiromi SHIMADA, ...1996 Volume 44 Issue 8 Pages 1440-1447
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFollowing the characterization of thunberginols A, B, and F, six bioactive principles, thunberginols C, D, and E, thunberginol G 3'-O-glucoside, (-)-hydrangenol 4'-O-glucoside, and (+)-hydrangenol 4'-O-glucoside, were isolated from Hydrangeae Dulcis Folium, the processed leaves of Hydrangea macrophylla SERINGE var. thunbergii MAKINO, together with four kaempferol and quercetin oligoglycosides. Their chemical structures have been determined on the basis of chemical and physicochemical evidence. Thunberginols C, D, E, and G and (-)-hydrangenol 4'-O-glucoside showed antiallergic activity in the in vitro bioassay using the Schultz-Dale reaction. These components also exhibited inhibitory activities on the histamine release from rat mast cells and on the histamine-induced contraction in isolated guinea pig tracheal chain. In addition, thunberginols C, D, E, and G showed antimicrobial activities against oral bacteria.View full abstractDownload PDF (1186K) -
Takashi MICHIDA, Hiroteru SAYO1996 Volume 44 Issue 8 Pages 1448-1453
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSCyclic voltammetry (CV) for 2, 7-disubstituted phenazines (1mM, MeO (1), EtO (2), H (3), Cl (4), Br (5), COOEt (6)) was carried out in acetonitrile containing trifluoroacetic acid (TFA, 1% and 2%) and NaClO4 (0.1M) as a supporting electrolyte under N2 gas. Phenazines showed two cathodic peaks (Epc1 and Epc2) and these peaks had counterparts (Epa1 and Epa2, respectively). Plots of the peak potentials against σp were linear. The first cathodic wave corresponds to the reduction of singly protonated phenazines followed by proton transfer. The second cathodic wave corresponds to the reduction of the cation radical of dihydrophenazines to produce dihydrophenazine as a final product.ESR spectrometry of 1-6 in acetonitrile and in acetonitrile containing 1% TFA was conducted and computer simulation of the spectra was carried out. Splitting due to halogen or o-alkyl substituents was observed. Molecular orbital (MO) calculation of anion radicals generated from 1-6 and cation radicals generated from doubly protonated 1-6 did not give good agreement with the results of ESR spectrometry.View full abstractDownload PDF (741K) -
Masayuki YOSHIKAWA, Toshiyuki MURAKAMI, Hisashi MATSUDA, Johji YAMAHAR ...1996 Volume 44 Issue 8 Pages 1454-1464
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFive bioactive triterpene oligoglycosides named escins Ia, Ib, IIa, IIb, and IIIa were isolated from the seeds of horse chestnut tree, Aesculus hippocastanum L. (Hippocastanaceae). The chemical structures of escins Ia, Ib, IIa, IIb, and IIIa were determined on the basis of chemical and physicochemical evidence, which included selective cleavage of the glucuronide linkage using photochemical reaction and lead tetraacetate decarboxylation reaction. Escins Ia, Ib, IIa, and IIb were found to exhibit an ethanol absorption-inhibitory effect and hypoglycemic activity in the oral glucose tolerance test in rats. Some structure-activity relationships are reported.View full abstractDownload PDF (1627K) -
Yoshisuke TSUDA, Yoshiyuki SATO, Kimihiro KANEMITSU, Shinzo HOSOI, Ken ...1996 Volume 44 Issue 8 Pages 1465-1475
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe 5, 6-O-thiocarbonyl-α-D-glucofuranose derivatives 2, when subjected to one of the following reactions, undergo a radical-promoted thione-thiol rearrangement to yield the 5-S-thiolcarbonates of gluco-configuration 8 as the major product. The reactions are, (A) thermolysis with a catalytic amount of tributyltin hydride and AIBN, (B) photolysis with hexabutyldistannane, and (C) thermolysis with dimethyl phosphonate and benzoyl peroxide. On the other, hand, theromolysis of 2 with trialkylsilane (condition D) yielded olefins 13 as the major product. The 5-S-gluco product 8 was converted, in three steps, to 5-thioglucose (21) in 55% yield.View full abstractDownload PDF (1590K) -
Yoshisuke TSUDA, Kenji SHIBAYAMA1996 Volume 44 Issue 8 Pages 1476-1479
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSO-Benzoyl, cyclic thionocarbonate, and thiolcarbonate groups in 5, 6-O-thiono-, 5, 6-O, S-thio-l, and 5, 6-S, O-thiolcarbonates of 3-O-benzoyl-1, 2-O-isopropylidene-α-D-glucofuranoses behaved differently on solvolysis under alkaline conditions. Generally, the 3-O-benzoyl group was the most vulnerable to NaOH in water or MeOH, while thionocarmonate and thiolcarbonate groups were more reactive than the O-benzoyl group toward methanolysis with NaOMe. In particular, methanolysis of the 5, 6-S, O-thiolcarbonate with NaOMe gave a thiirane derivative very rapidly.View full abstractDownload PDF (591K) -
Hatsuo MAEDA, Takashi KOIDE, Sayaka MATSUMOTO, Hidenobu OHMORI1996 Volume 44 Issue 8 Pages 1480-1483
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSReplacement of hydroxyl groups in secondary and primary alcohols (1) with a fluorine atom arising from tetrafluorobote anion has been performed by the electrochemical formation of alkoxy triphenylphosphonium tetrafluoroborarates (2) from 1, followed by their thermal decomposition. The procedure is quite simple, involving : (1) constant-current electrolysis of a mixture of 1, Ph3P, and Ph3PH·BF4 in CH2Cl2 in an undivided cell; (2) refluxing a tetrahydrofuran or dioxane solution of the residue afforded by evaporation of the solvent in vacuo after the electrolysis. Cyclic secondary alcohols such as 3β-hydroxy steroids and 2-adamantanol are transformed into the corresponding fluorides in satisfactory yields when the geometry of the leaving group in 2 is suitable for the substitution or an elimination process for 2 to give an alkene is stereochemically forbidden. The fluorination of steroidal alcohols and 4-phenyl-1-cyclohexanol proceeded with complete inversion, demonstrating that a fluorine atom from the tetrafluoroborate anion attacks from the side opposite to the phosphonium moiety in 2 via an SN2 mechanism rather than as SN1 mechanism. The fluorination of acyclic secondary and primary alcohols was performed by the present method in reasonable yields, although the reaction for the latter required more forcing conditions, such as refluxing in dioxane.View full abstractDownload PDF (743K) -
Shiro KATO, Toshiya MORIE, Naoyuki YOSHIDA1996 Volume 44 Issue 8 Pages 1484-1492
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTo confirm the proposed structures of the minor metabolites of a potential gastroprokinetic agent, mosapride, 4-amino-5-chloro-2-ethoxy-3-hydroxy-N-(2-morpholinylmethyl)benzamide (3) and the N-(5-oxo-2-morpholinyl)-methyl analogue 4 were prepared. As the common intermediate, 2-ethoxy-3-hydroxy-4-nitrobenzoic acid (15) was propared via the regioselective ethylation of 2, 3-dihydroxybenzaldehyde (10) and subsequent nitration of the resultant 2-ethoxy-3-hydroxybenzaldehyde (11). The key intermediate 15 was converted into the benzamides 3 and 4. After enzymatic treatment of the isolated metabolites, their structures were identified by comparison with the synthetic compounds. Serotonin-4 receptor binding affinity of these metabolites was found to be lower than that of mosapride.View full abstractDownload PDF (1390K) -
Teizi URAKAMI, Akinobu TANAKA, Tsuyoshi TANIMOTO, Etsuo NIKI1996 Volume 44 Issue 8 Pages 1493-1497
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSDerivatives of imidazopyrroloquinoline (IPQ) and its esters were synthesized. Some of these compounds potently inhibited aldose reductases of rabbit lens and dog kidney, as well as the human recombinant enzyme, though the coenzyme pyrroloquinoline quinone (PQQ) was a relatively poor inhibitor. The IPQ esters with a methyl substituent at the C-3 carboxyl group were less potent inhibitors than the analogs without esterification at this position. An IPQ ester with the free carboxyl group at C-3 inhibited sorbitol accumulation in rat red blood cells.View full abstractDownload PDF (804K) -
Fumio ITOH, Yoshio YOSHIOKA, Koichi YUKISHIGE, Sei YOSHIDA, Megumi WAJ ...1996 Volume 44 Issue 8 Pages 1498-1509
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe glutamic acid moiety of N-[4-[3-(2, 4-diamino-7H-pyrrolo[2, 3-d]pyrimidin-5-yl)propyl]benzoyl]-L-glutamic acid (1b, TNP-351) and related compounds was replaced with some N5-substituted glutamines. Antifolates (4A-S) were effectively prepared by coupling pyrrolo[2, 3-d]pyrimidine carboxylic acids (11a, b) with some properly protected N5-substituted glutamine derivatives (10A-S), which were prepared by coupling Boc-Glu-OMe (7) with various amines (8A-S) using a suitable condensing reagent, followed by hydrolysis. The inhibitory effects of the resulting products on dihydrofolate reductase (DHFR), thymidylate synthetase (TS) and the growth of murine fibrosarcoma Meth A cells in culture were examined. All N5-substituted glutamine analogs (4A-S) inhibited DHFR much more strongly than TNP-351 and some analogs exhibited the same potent growth inhibition of Meth A cells as TNP-351. Some typical analogs (4Bb, 4Db, 4F, 4Oa) were also examined for inhibitory effects on the growth of methotrexate (MTX)-resistant human CCRF-CEM cells in culture and for in vivo antitumor activities against murine leukemia and solid tumors. MTX-resistant cells, with a defect in transport and decreased polyglutamylation activity, showed little cross resistance to the analog (4Oa) having a tetrazole moiety as a substituent of glutamine, which exhibited potent antitumor activities. These results demonstrate that the antifolate analogs (4) with N5-substituted glutamine in place of glutamic acid are novel potent DHFR inhibitors with activity against MTX-resistant tumors. The potent antitumor activity of these analogs (4) may result from their effective uptake via reduced folate carrier in combination with their potent inhibition of DHFR.View full abstractDownload PDF (2014K) -
Shunichiro SAKURAI, Nobuo OGAWA, Tomio SUZUKI, Ken-ichi KATO, Tetsuo O ...1996 Volume 44 Issue 8 Pages 1510-1520
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAs part of our search for a dual inhibitor possessing both thromboxane A2 (TXA2) receptor antagonistic and TXA2 synthase inhibitory activities, some [[(benzenesulfonamido)alkyl]phenyl]alkanoic acid derivatives possessing a pyridyl or imidazolyl group were synthesized. Their TXA2 receptor antagonistic and TXA2 synthase inhibitory activities were evaluated in terms of the inhibitory effects on U-44619-induced guinea-pig platelet aggregation and on thromboxane B2 (TXB2) production in human platelets, respectively. It was found that 3-[4-[2-(1-imidazolyl)-1-(4-chlorobenzenesulfonamido)ethyl]phenyl]propionic acid (22a), containing an imidazolyl group, is a well-balanced dual inhibitor having both TXA2 receptor antagonistic activity (IC50=0.31μM) and TXA2 synthase inhibitory activity (IC50=0.39μM).View full abstractDownload PDF (1471K) -
Yoshiohiro ABE, Tomoko SHOJI, Shikie FUKUI, Maki SASAMOTO, Hideyuki NI ...1996 Volume 44 Issue 8 Pages 1521-1524
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSEnantioseparation of (±)-propranolol has been demonstrated by countercurrent extraction with a two-phase system composed of a chloroform solution of didodecyl L-tartrate (100mM) and an acetate buffer (50mM, pH 4.4) containing boric acid (100mM). The free base of (±)-propranolol (1.6g) was dissolved in the aqueous phase and extracted five times by means of dual-flow countercurrent extraction. After an additional five extractions for recovery, the crude R-(+)- or S-(-)-form was obtained from the aqueous extracts or organic extracts, respectively. They were isolated as their hydrochloride salts with a purity of 89.8% ee (R-form, 385.7mg) and 88.3% ee (S-form, 429.5mg), respectively. They were purified to over 99% ee by recrystallizing twice from 1-propanol.View full abstractDownload PDF (626K) -
Naotaka KURODA, Yuko OHYAMA, Kyoko NAKASHIMA, Kenichiro NAKASHIMA, Shu ...1996 Volume 44 Issue 8 Pages 1525-1529
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSCarnitine and acylcarnitines are important substances involved in the oxidation and metabolism of fatty acids. An HPLC method is presented for the quantitative analysis of these compounds. The method is based on the detection of fluorescent derivatives of carnitine and short- and medium-chain acylcarnitines labeled with 2-(4-hydrazinocarbonylphenyl)-4, 5-diphenylimidazole (HCPI). The labeling of carnitine and acylcarnitines with HCPI was performed at room temperature for 1h using 1-ethyl-3-(3-dimethylaminopropyl)carbodimide as a condensing reagent. The analytes prepared using cation-exchange cartridges were separated on an octadecylsilyl silica gel (ODS) column by a gradient elution system of acetonitrile/Tris-HCl buffer and determined using a synthetic internal standard. Fluorescence detection was performed at 475nm with excitation at 340nm. The detection limits for carnitine, acetyl-, propionyl-, hexanoyl- and octanoylcarnitine ranged from 0.24 to 1.97nmol per ml human plasma, at a signal-to-noise ratio of 3. The within-day and between-day precision of the assay for carnitine and acylcarnitines in plasma samples had relative standard deviations (RSDs) lower than 10.3%. The concentration of free carnitine, acylcarnitines and total carnitine in human plasma could be successfully determined by the proposed method.View full abstractDownload PDF (728K) -
Mitsuteru NUMAZAWA, Akiko YOSHIMURA1996 Volume 44 Issue 8 Pages 1530-1534
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA series of 6α- and 6β-alkylestradiols (5 and 6) (alkyl : methyl, ethyl, n-propyl, n-pentyl, and n-heptyl) were synthesized as possible aromatase reaction products of 6-alkylandrost-4-ene-3, 17-diones and their Δ1-derivatives, potent competitive and mechanism-based inhibitors of aromatase. Treatment of 6-oxoestradiol with Grignard reagents followed by acid-catalyzed dehydration and subsequent catalytic hydrogenation over Pd-C gave the 6-alkylestradiols (5 and 6). GC-MS (electron impact mode) of trimethylsilyl derivatives of bis-trimethylsilyl derivatives of compounds 5 and 6 revealed that the 6α-alkyl compounds, 5, emerged with a longer retention time compared to the corresponding 6β-alkyl isomers, 6, where the retention time was in proportion to the length of the 6-alkyl chain in each series. In the MS, a molecular ion (M+) peak was the base peak for all the 6-alkylestrogens, with strong and characteristic fragment ion peaks corresponding to M+-131 and at m/z 325. A selected ion monitoring method using a molecular ion will be sensitive enough for analysis of the aromatization reaction of the 6-alkylandrogens.View full abstractDownload PDF (733K) -
A New Series of Coumarin Derivatives Having Monoamine Oxidase Inhibitory Activity from Monascus ankaChowdhury Faiz HOSSAIN, Emi OKUYAMA, Mikio YAMAZAKI1996 Volume 44 Issue 8 Pages 1535-1539
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSMonankarins A-F (1-6), a new series of pigments having conjugated pyrano-coumarin skeleton have been isolated from Monascus anka. Their structures have been elucidated by spectroscopic means and chemical modification. Monankarins A-D exhibited monoamine oxidase (MAO) inhibitory activity, while the activity was not observed in monankarins E and F or some other simple coumarins. Monankarin C (3) showed stronger inhibition of MAO-B than MAO-A in mice brain. However, the specificity was not found in mice liver MAO.View full abstractDownload PDF (913K) -
Akiko OHNO, Haruhisa KIZU, Tsuyoshi TOMIMORI1996 Volume 44 Issue 8 Pages 1540-1545
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFrom the aerial part of Scutellaria discolor, eight new neoclerodane diterpenes (compounds 3, 4, 6, 8, 9, 10, 11 and 12) were isolated together with clerodin, dihydroclerodin-I, clerodin hemiacetal (14-hydro-15β-hydroxyclerodin), jodrellin A, scutaltisin, squalene, 24-methylenecycloartanol and a mixture of 3-epioleanolic acid and 3-epiursolic acid. The structures of new compounds were determined by spectroscopic and chemical methods as follows : 3, 15β-ethoxy-14-hydroclerodin; 4, 15α-ethoxy-14-hydroclerodin; 6, (6α)-19-O-acetyl-4, 18 : 11, 16 : 15, 16-triepoxyneoclerodane-6, 15, 19-triol (6-O-deacetyl-14-hydro-15-hydroxyclerodin); 8, 6α-O-acetyl-2, 19 : 4, 18 : 11, 16 : 15, 16-tetraepoxy-14-neoclerodene-6, 19-diol (19-O-deacetyljodrellin A); 9, 10, 11, and 12, 6α-O-acetyl-15β, 19β-di-O-ethyl-, 6α-O-acetyl-15α, 19β-di-O-ethyl-, 6α-O-acetyl-19β-O-ethyl- and 6α, 19-di-O-acetyl-2, 19 : 4, 18 : 11, 16 : 15, 16-tetraepoxyneoclerodane-6, 15, 19-triol, respectively.View full abstractDownload PDF (1054K) -
Hiroyasu KOKUBO, Hisakazu SUNADA1996 Volume 44 Issue 8 Pages 1546-1549
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA model system consisting of lactose-cornstarch-microcrystalline cellulose with hydroxypropyl methylcellulose 2910 (HPMC 3cP) as a binder was used to estimate the effects of process variables (granulation time, amount of granulating water and impeller speed) on the particle size distribution of granules prepared in a high-speed mixer using a dry mixing method of binder addition. The distribution of binder in different size fractions of granules was also determined by measuring the contents of methoxyl group. The binder content interpolated at the median particle size was close to the theoretical value calculated from the formulation. Longer granulation time, greater amount of granulating water and higher impeller speed increased the granule size and strength. An expanded binder distribution was seen at higher impeller speed. At extremely short granulation time (1 mins), the granules were friable and the binder content in the larger size fraction of the granules changed during fluid-bed and tray drying because of insufficient binder dissolution or granular compaction. Binder behavior during wet granulation seems to be closely related to the observed differences in granule strength.View full abstractDownload PDF (635K) -
Kuniaki ISHII, Yoko SAITOU, Ryota YAMADA, Shigeru ITAI, Masami NEMOTO1996 Volume 44 Issue 8 Pages 1550-1555
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new approach to determination of good correlations between in vivo and in vitro dissolution was studied using the optimization technique. Ibuprofen, which exhibits dissolution rate-limiting absorption, was used as a model drug. Ibuprofen capsules of two different release types were prepared, and their in vivo dissolution profiles were obtained from measurements of plasma concentration following oral administration of the capsules to beagle dogs by the mathematical deconvolution method using solution data of oral administration as a weight function. For the dissolution test to correspond to the in vivo dissolution profiles, the test was carried out at 12 levels (9 different sets of conditions) and results were analyzed with the optimization technique to deal with two factors. The first-order rate constant (kd) and the dissolution time at 50% (t50%) of the in vivo dissolution were selected for use as the response variables. Regression analysis was performed to describe the in vitro dissolution characteristics as functions of the pH of dissolution medium and paddle rotation speed in the paddle method. The in vivo/in vitro correlation obtained from the kd was better than that obtained from the t50%. The optimum conditions for dissolution testing corresponding to the in vivo kd were determined to be a pH 6.6 for the dissolution medium and a 56 rpm paddle rotation rate. The experimental data obtained by dissolution testing was well fit by the predicted curve derived from in vivo and in vitro dissolution profiles. This dissolution test is applicable to the formulations containing ibuprofen of particle size within the experimental range.View full abstractDownload PDF (840K) -
Satoru WATANO, Yoshinobu SATO, Kei MIYANAMI1996 Volume 44 Issue 8 Pages 1556-1560
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIn this paper, the control of granule growth in fluidized bed granulation was carried out using a newly developed image processing system. Granule images measured by a particle image probe were digitized by an image processing system during granulation to continuously calculate granule size distribution. To avoid excessive granule growth, fuzzy logic using a linguistic algorithm employing if-then rules with a process lag element taken into consideration was adopted for the control algorithm. This newly developmed system was applied to actual fluidized bed granulation under various powder samples and operating conditions, and the validity of the system was investigated. It was found tha the system could control granule growth with high accuracy, regardless of changes in powder samples and operating conditions.View full abstractDownload PDF (755K) -
Yukinori KAWAI, Kyuichi MATSUBAYASHI1996 Volume 44 Issue 8 Pages 1561-1566
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSEbselen is an organoselenium compound that exhibits a glutathione peroxidase-like activity. The kinetics of ebselen degradation in basic aqueous solution containing primary alcohol was investigated by HPLC. The reversible reaction of ebselen and its dimer (diselenide) was discovered as a novel redox reaction. This reaction followed first-order degradation in basic solution at a constant temperature, and the equilibrium constants of ebselen and diselenide depended on pH. Analysis of the degradation rate for the forward reaction-pH profile indicated that specific base catalysis occurs in ebselen. The mechanism of this redox reaction was investigated by HPLC, spectrophotometry and trapping the labile intermediate with trichloroethylene. Ebselen decomposes to diselenide via selenenic acid and selenol by reacting with primary alcohol. The deuterium isotope effect on the forward reaction indicated that the reaction rate depends on the strength of the hydrogen-carbon bond at the α-position of primary alcohol. On the other hand, the effect of nitrogen replacement on the reverse reaction showed that diselenide is converted into ebselen by oxidation with oxygen existing in the solution.View full abstractDownload PDF (802K) -
Masahiro FUKAHORI, Sakae AKATSU, Hiroshi SATO, Toshihisa YOTSUYANAGI1996 Volume 44 Issue 8 Pages 1567-1570
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe relationship between the uptake and antimicrobial activity of p-hydroxybenzoic acid esters (parabens) was studied using Escherichia coli. The uptake into bacterial cells and the antibacterial activity of parabens were logarithmically proportional to the carbon number of the alkyl group from methyl to butyl paraben. The free energy change for the transfer of the methylene group of parabens from the aqueous to the cell phase was less than that obtained from the n-hexane and n-octanol-water partition systems. This demonstrates that the hydrophilicity of the cells is larger than n-hexane and n-octanol. The uptake of hydrophobic ethyl benzoate was less than that of the more hydrophilic butyl paraben possessing a phenolic hydroxyl group. Parabens may thus be incorporated into cells by both hydrophobic and hydrophilic interactions. The apparent concentration of parabens in the bacterial cells required to produce the same antibacterial activity decreased logarithmically with an increasing carbon number of the alkyl group. The dependence of the antibacterial activity of parabens on the alkyl chain length may thus be concluded to be due to the alkyl group, not only for uptake into bacterial cells but also for accumulation or concentration on biological receptors after incorporation into the cells.View full abstractDownload PDF (752K) -
Pascale GAILLARD, Marcelle HAUTEVILLE, Madeleine PICQ, Marie-Christine ...1996 Volume 44 Issue 8 Pages 1571-1576
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA series of eight methoxylated C-methyl-2-phenyl-4H-1-benzopyran-4-ones 3, 6, 10-15 was evaluated as inhibitors of rat heart cytosolic cyclic nucleotide phosphodiesterase (PDE). The 2-(3, 4-dimethoxyphenyl)-5, 7-dimethoxy-3, 8-dimethyl-4H-1-benzopyran-4-one (3) and the 2-(4-methoxyphenyl)-5, 7-dimethoxy-3, 8-dimethyl-4H-1-benzopyran-4-one (10) have never been previously described. Inhibition was performed on the whole cytosolic preparation and on the four PDE isoforms after HPLC purification. The flavones 3, 6, 10, 13 and 14 were selective and potent inhibitors of the isoforms, namely ROI (rolipram-sensitive) and CGI (cGMP-sensitive) PDEs specifically hydrolyzing cAMP. The di-C-methylflavones 3 and 13 have been shown to be potent inhibitors of these two isoforms, with IC50 values in the micromolar range.View full abstractDownload PDF (913K) -
Haruo SEKIZAKI, Kunihiko ITOH, Eiko TOYOTA, Kazutaka TANIZAWA1996 Volume 44 Issue 8 Pages 1577-1579
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA facile synthetic method for p-guanidinophenyl esters derived from a variety of amino acids and peptides, including D-amino acids, is presented. The kinetic behavior of trypsin towards these synthetic esters, inverse substrates, was analyzed. The spatial requirement of the enzyme active site for catalytic efficiency is discussed based on the steric characteristics of the substrates.View full abstractDownload PDF (612K) -
Kazuhiro NOJIMA, Chiho ISOGAMI1996 Volume 44 Issue 8 Pages 1580-1584
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAldrin (1) was found to undergo epoxidation and isomerization, when irradiated at wavelengths longer than 290 nm in the presence of benzaldehyde in air, to give dieldrin (2) and photoaldrin (1, 1, 2, 3, 3a, 7a, -hexachloro-2, 3, 3a, 3b, 4, 6a, 7, 7a-octahydro-2, 4, 7-metheno-1H-cyclopenta[a]pentalene, 3), respectively, followed by isomerization or epoxidation, respectively, to afford photodieldrin (1, 1, 2, 3, 3a, 7a-hexachloro-5, 6-epoxy-decahydro-2, 4, 7-metheno-1H-cyclopenta[a]pentalene, 4) in each case. The predominant photo-products were the epoxides, 2 and 4. These photo-products were also formed when a mixture of 1 and benzaldehyde in air was exposed to sunlight.View full abstractDownload PDF (661K) -
Haruo SEKIZAKI, Kunihiko ITOH, Eiko TOYOTA, Kazutaka TANIZAWA1996 Volume 44 Issue 8 Pages 1585-1587
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTrypsin-catalyzed peptide synthesis has been studied by using p-guanidinophenyl esters of Nα-(tert-butyloxycarbonyl)amino acid and peptide as acyl donor components. The reaction conditions were optimized for organic solvents, pH, and concentration of acceptor. The method was especially useful for the preparation of various peptides containing D-amino acids. The enzymatic hydrolysis of the resulting products was negligible.View full abstractDownload PDF (515K) -
Takashi MATSUMOTO, Yoshio TAKEDA, Kimiko SOH, Hiroyuki MATSUMURA, Sach ...1996 Volume 44 Issue 8 Pages 1588-1590
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS5, 8, 11, 13-Abietatetraen-3-one (3) and its 12-methoxy derivative (7) were oxidized to the corresponding 3, 7-diones, which were rearranged respectively into 2-isopropyl-6-methyl-5-(4-methyl-3-oxopentyl)naphthalene (6) and its 12-methoxy derivative (10) by sodium borohydride reduction and subsequent dehydration with boron trifluoride etherate. Compound 10 was further converted into 3-oxosapriparaquinone (1) via 5-(3-acetoxy-4-methylpentyl)-2-isopropyl-6-methyl-3, 4-naphthoquinone (14).View full abstractDownload PDF (618K) -
Yeh-Long CHEN, Tai-Chi WANG, Shiu-Chuan LIANG, Che-Ming TENG, Cherng-C ...1996 Volume 44 Issue 8 Pages 1591-1595
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIn a search for new inhibitors of platelet aggregation, certain coumarin-bearing α-methylene-γ-butyrolactones were synthesized and evaluated for inhibitory activity against thrombin (Thr)-, arachidonic acid (AA)-, collagen (Col)-, and platelet-activating factor (PAF)-induced aggregation in washed rabbit platelets. These compounds were efficiently synthesized from commercially available 7-hydroxycoumarin or its derivative. Among them, 7-[(2, 3, 4, 5-tetrahydro-4-methylene-5-oxo-2-phenyl-2-furanyl)methoxy]-2H-1-benzopyran-2-one (3d) showed the most potent inhibition of AA- and PAF- induced aggregation, with IC50 values of 3.65 and 16.36μM respectively.View full abstractDownload PDF (938K) -
Takafumi FUJIOKA, Shuji TERAMOTO, Sachiko TSUJIMI, Kazumi TAKEMOTO, To ...1996 Volume 44 Issue 8 Pages 1596-1598
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe enanitomers of 6-[3-(3, 4-dimethoxybenzylamino)-2-hydroxypropoxy]-2(1H)-quinolinone (OPC-18790), a novel cardiotonic agent, were synthesized and evaluated for positive inotropic activity. The key intermediates, 2, 3-epoxypropoxy derivatives, were obtained by the alkylation of 6-hydroxy-2(1H)-quinolinone with optically active epichlorohydrin and subsequent ring closure.View full abstractDownload PDF (494K) -
Shin IGUCHI, Kenichi HIRANO, Hiroshi OKAMOTO, Yoshiko OKAMOTO, Yoshio ...1996 Volume 44 Issue 8 Pages 1599-1602
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSStereoisomers of thiol proteinase inhibitor (TPI) were synthesized by a conventional solution method. Among them, iNoc-D-Gln-Val-Ala-Ala-pNA weakly inhibited the aminolytic activity of papain, although iNoc-Gln-Val-Val-Ala-Ala-pNA inhibited papain activity fairly potently. However, the other five D-amino acid-containing peptides did not show any inhibitor effects on papain. The circular dichroism (CD) spectra of the enzyme-peptides mixtures were measured in order to study the relationship between the peptide anilides-papain interaction and the inhibitory activity.View full abstractDownload PDF (627K) -
Makoto MORITA, Hiroshi NAKANISHI, Hiroshi MORITA, Susumu MIHASHI, Hide ...1996 Volume 44 Issue 8 Pages 1603-1606
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSesquiterpenes isolated from Alpinia speciosa and Alpinia japonica, and their derivatives were found to inhibit histamine- or barium chloride-induced contraction of excised guinea pig ileum when tested by the Magnus method. Major spasmolytic principles contained in those extracts were the sesquiterpenes, β-eudesmol, nerolidol, humulene epoxide II and 4α-hydroxydihydroagarofuran. Relationships between the chemical structures of the sesquiterpenes and their derivatives, and their spasmolytic activities were discussed.View full abstractDownload PDF (718K) -
Eiichi KANAI, Koichi MACHIDA, Masao KIKUCHI1996 Volume 44 Issue 8 Pages 1607-1609
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThree new iridoids, named kisasagenols A (1), B (2) and epicatalpin (3), were isolated, together with two artifactual iridoids, 3-methoxy catalpin (4) and 3-methoxy epicatalpin (5), from Catalpae Fructus. Their structures were established on the basis of spectral analysis.View full abstractDownload PDF (544K) -
Toshio MIYASE, Ryouko YAMAMOTO, Akira UENO1996 Volume 44 Issue 8 Pages 1610-1613
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFour new diterpene glycosides, betonicosides A-D and a new diterpene, betonicolide, were isolated from the roots of Stachys officinalis. The structures of these compounds were established on the basis of spectroscopic and chemical evidence.View full abstractDownload PDF (587K) -
Yuji CHIKARAISHI, Makoto OTSUKA, Yoshihisa MATSUDA1996 Volume 44 Issue 8 Pages 1614-1617
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWe prepared piretanide polymorphs by a new recrystallization procedure maximizing the solubility difference based on the pH difference of the solution. A new polymorph, form C, was formed at an acid-base molar ratio of ≥1 : 1, and amorphous form at <0.975 : 1. At the molar ratio of HCl being 0.975-1, a mixture of form C and the amorphous form was generated. By X-ray powder diffractometry, the amorphous form showed no diffraction peak, and form C was significantly different from forms A (bulk material, BM) and B (polymorph). FT-IR spectra of form C and the amorphous form were significantly different from those of forms A and B at around 1700 and 3200-3400 cm-1. The DSC curve of the amorphous form showed exothermic peaks at 136 and 209°C and endothermic peaks at 207 and 225°C (corresponding to the melting point of BM), whereas that of form C showed an exothermic peak at 143°C and endothermic peaks at 132 and 224°C (corresponding to the melting point of BM). By the dispersed amount method, the solubilities of the amorphous form and form C were almost the same as that of form B and 2.0- and 1.4-fold higher than that of form A (8.3mg/100ml) in JPXII first fluid (pH 1.2) and were about 4.5-fold higher than those of forms A and B (about 200mg/100ml) in JPXII second fluid (pH 6.8) at 37°C.View full abstractDownload PDF (928K) -
Tetsu MORIMURA, Yoshifumi NOBUHARA, Hayashi MATSUKURA1996 Volume 44 Issue 8 Pages 1618-1620
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe degradation kinetics of sparfloxacin (5-amino-1-cyclopropyl-7-(cis-3, 5-dimethyl-1-piperazinyl)-6, 8-difluoro-1, 4-dihydro-4-oxoquinoline-3-carboxylic acid) were examined as functions of pH (1.0-10.5), temperature (100-120°C) and buffer concentration (0.01-0.05 M).The degradation kinetics for sparfloxacin in aqueous solution followed a pseudo-first-order reaction under all experimental conditions. No appreciable effect of buffer species on the degradation of sparfloxacin was observed within the experimental conditions. The log k-pH profiles showed specific-acid catalysis at a pH below 4.0, and there were inflection points near pH 6 and 9 corresponding to the pKa1 and pKa2 values. Arrhenius data in this study showed that the degradation of sparfloxacin was negligible at room temperature between pH 1.0-10.5.View full abstractDownload PDF (469K) -
Ae-Ri Cho LEE, Kakuji TOJO1996 Volume 44 Issue 8 Pages 1621-1623
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAn evaluation method is proposed for the intrinsic skin permeation rate of unstable compounds. Vitamin C and vitamin E were used as the model compounds. The degradation of vitamin C and E in the solutions followed first-order kinetics with degradation constants of 0.26h-1 and 0.014h-1, respectively. The apparent skin permeation profiles of vitamin C and E in vitro, approximated by a nonlinear profile of the polynomial regression method, was corrected for intrinsic permeation rate considering first-order degradation in the receptor solution. The intrinsic profiles evaluated agreed well with the ones determined from radio-labelled compounds, indicating the feasibility of the present analysis.View full abstractDownload PDF (556K) -
Makiko YAMADA, Mikio NAKAMURA, Takashi YAMADA, Tamio MAITANI, Yukihiro ...1996 Volume 44 Issue 8 Pages 1624-1627
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSMajor unknown subsidiary colors A (Sub A) and B (Sub B) in commercial Sunset Yellow FCF (Food Yellow No. 5 in Japan) have been isolated by preparative HPLC. Spectroscopic analyses of Sub A and Sub B revealed that their structures are trisodium salt of 6-hydroxy-7-(4-sulfophenyl)-5-(4-sulfophenylazo)-2-naphthalenesulfonic acid, and disodium salt of 3-hydroxy-4-(4-sulfophenylazo)-2-naphtalenesulfonic acid, respectively.View full abstractDownload PDF (590K) -
Fumihiro NAGASHIMA, Akiko TAMADA, Yoshinori ASAKAWA1996 Volume 44 Issue 8 Pages 1628-1630
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new monocyclic diterpene, infuscatrienol (1), has been isolated from the liverwort Jungermannia infusca and its structure determined by extensive spectroscopic analysis.View full abstractDownload PDF (394K) -
Hideaki MURATAKE, Miyuki TONEGAWA, Mitsutaka NATSUME1996 Volume 44 Issue 8 Pages 1631-1633
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAlternative synthesis of duocarmycin SA (1) was achieved by developing a novel preparation method using palladium catalysts for a tricyclic heteroaromatic compound 4b, followed by transformation into the previously reported intermediates 13 and 14a by way of the alcohol 10b.View full abstractDownload PDF (505K) -
Takashi HARAYAMA, Toshihiko AKIYAMA, Kazuko KAWANO1996 Volume 44 Issue 8 Pages 1634-1636
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTotal synthesis of chelerythrine, a benzo[c]phenanthridine alkaloid, was accomplished via the internal aryl-aryl coupling reaction of halo-amide (4) by the palladium-assisted cyclization reaction.View full abstractDownload PDF (438K) -
Norio AIMI, Mariko KITAJIMA, Naoko OYA, Wataru NITTA, Hiromitsu TAKAYA ...1996 Volume 44 Issue 8 Pages 1637-1639
Published: August 15, 1996
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo monoterpenoid indole alkaloids and four β-carbolines were isolated from a hydrid cell suspension culture generated from two Apocynaceous plants, Rauwolfia serpentina Benth. and Rhazya stricta Decaisne. This indicates that the function of alkoloid biosynthesis is retained after hybrid formation and that alkaloids not previously detected in the parental plants or cell cultures are formed.View full abstractDownload PDF (532K)
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