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Volume 47, Issue 10
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Kanakapura BASAVAIAH, Gopalaiah KRISHNAMURTHY, Javarappa MANJUNATHA SW ...1999 Volume 47 Issue 10 Pages 1351-1354
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA titrimetric and a spectrophotometric method herein described for the determination of phenothiazine psychotropics. In the titrimetric method, phenothiazines are reacted with a known excess of potassium dichromate under acidic conditions and after the completion of the reaction, unreacted dichromate is backtitrated with ammonium ferrous sulphate. In the spectrophotometric method, the unreacted dichromate is reacted with s-diphenylcarbazide under acidic conditions and the absorbance measured at 540 nm. The proposed methods were successfully applied to the determination of phenothiazines in pharmaceutical preparations. The reliability of the assays was established by parallel determination by the official methods of British pharmacopoeia.View full abstractDownload PDF (689K) -
Hiromasa NAGASE, Haruhisa UEDA, Masayuki NAKAGAKI1999 Volume 47 Issue 10 Pages 1355-1362
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe effects of sonication, conducted prior to dehydration by heat drying, on the multilamellar vesicles of L-α-dipalmitoyl phosphatidylcholine (DPPC), DPPC/glucose, DPPC/trehalose or DPPC/maltose systems were examined by differential scanning calorimetry (DSC) and powder X-ray diffraction (XRD). The results were compared with those for the corresponding unsonicated and DPPC systems without saccharide. In the DPPC/glucose system, no clear differences between the unsonicated and sonicated systems were found because glucose did not prevent fusion of vesicles by dehydration. DSC showed one sharp peak at the gel-liquid crystal transition temperature (Tc) of 43°C, indicating that glucose was distributed homogeneously between the DPPC bilayers of the vesicles. Subcells formed by hydrocarbon chains of DPPC changed from the hexagonal gel (Lβ) to the hexagonal liquid crystal (Lα) form at Tc with an increase in temperature, essentially as noted for DPPC systems except for differences in Tc. In the DPPC/disaccharide system, the unsonicated and sonicated systems were clearly different. DSC and XRD of the unsonicated system consistently showed transition from a gel to a liquid crystal state over a wide temperature range, while for the sonicated system, there was only a sharp peak on the DSC curve. The thermal behavior of DPPC/disaccharide systems may be explained as follows. Although disaccharide is distributed homogeneously between the bilayers of multilamellar vesicles, interactions with DPPC depend on the surface curvature of the bilayer. Heating of multilamellar vesicles may possibly result in transition from a gel to a liquid crystal phase since multilamellar vesicles consist of many bilayers differing considerably in their surface curvature, in contrast to sonicated unilamellar vesicles which possess a definite curvature.View full abstractDownload PDF (1167K) -
Kuniharu UTSUNO, Yoshimi MAEDA, Masamichi TSUBOI1999 Volume 47 Issue 10 Pages 1363-1368
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe effect of Hoechst 33258 binding on the geometry of a DNA duplex (plasmid pBR322) has been examined using topoisomerase II relaxation followed by gel electrophoresis. Of this drug-DNA system, fluorescence, optical absorption, and calorimetric measurements were also made at various drug and DNA concentrations and in the same buffer as that for the topoisomerase reaction. It has been confirmed that there are two modes of drug-DNA interaction. When the drug concentration is much lower than the DNA base pair concentration, the Hoechst 33258 molecule binds in the minor groove of the DNA duplex and occupies a site formed of five continuous base pair sequences that contain no G·C pair. Here, the equilibrium constant K1 is 1.8×107M-1 (at 37°C), and the enthalpy of binding ΔH1 is -865 cal/mol. When the drug concentration is much higher, on the other hand, it shows another binding mode which is much weaker, so that K2=2.25×104M-1 and ΔH2 is -464 cal/mol, which gives fluorescence quenching, which has no base pair preference, and which causes an unwinding of the duplex by 1 degree.View full abstractDownload PDF (1226K) -
Yasushi SENBA, Tsukasa NISHISHITA, Keiko SAITO, Hiroe YOSHIOKA, Hisash ...1999 Volume 47 Issue 10 Pages 1369-1374
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSRadical scavenging of four tea catechins, (-)-epicatechin (EC), (-)-epigallocatechin (EGC), (-)-epicatechin gallate (ECg) and (-)-eppigallocatechin gallate (EGCg), and the model compounds of their partial structure was examined against the 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical using stopped-flow and spectrophotometric methods. The number of DPPH radicals scavenged by a polyphenol molecule was larger than that of phenolic hydroxyl groups, suggesting that hydrogens which bond directly to the aromatic ring can also participate in radical scavenging. A model for the scavenging reaction was proposed in which the reaction proceeded with successive dehydrogenation from a polyphenol molecule. Analysis of the second order reaction rate constants and the activation parameters between DPPH and polyphenol at the early stage of the reaction showed that the values depended on the number of phenolic hydroxyl groups and their mutual position. Contribution of the A ring of catechins to the rate constants was estimated to be far smaller than that from the B ring. In the EGCg molecule, the B ring and the gallate group were not independent, but acted as a single group for DPPH radical scavenging.View full abstractDownload PDF (836K) -
Yumiko UENO, Hirokazu MATSUNAGA, Kazuichi UMEMOTO, Koji NISHIJIMA1999 Volume 47 Issue 10 Pages 1375-1379
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSHPLC using the fluorescent reagent, 4-(N, N-dimethylaminosulfonyl)-7-N-piperazino-2, 1, 3-benzoxadiazole (DBD-PZ) was applied to the determination of free fatty acids in an o/w injectable emulsion. This fluorescence HPLC method was highly sensitive and the free fatty acids could be directly derivatized without any previous preparation such as solvent extraction and elimination of water. In addition, the derivatized fatty acids could be adequately separated from interfering peaks, i.e., reagent and by-product peaks.The detection limit of this HPLC method was ca. 5 fmol in the case of C18 : 0 fatty acid. The mean recovery of 2.5 nmol of each fatty acid (C8 : 0, C14 : 0, C16 : 0, C18 : 0) added to the o/w injectable emulsion was 101.6% (n=3). This fluorescence HPLC method with DBD-PZ was applied to commercial nonaqueous injection preparations to study their stability, and each free fatty acid in these preparations could be determined successfully. These results indicate that the proposed fluorescence HPLC method can be adequately used for the determination of free fatty acids in an o/w injectable emulsion.View full abstractDownload PDF (710K) -
Masatoshi MURAKATA, Yusuke MIZUNO, Hiromi YAMAGUCHI, Osamu HOSHINO1999 Volume 47 Issue 10 Pages 1380-1383
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS(R)-3-Methoxymethyl-3-propyl-3, 4-dihydrocoumarin was synthesized, starting from a chiral Michael adduct [(S)-methyl 2, 3-dihydro-1-oxo-2-(3-oxobutyl)-1H-indene-2-carboxylate], in order to determine the absolute configurations of the products obtained by enantioselective radical-mediated allylation. Aldol cyclization of the Michael adduct proceeded smoothly with suppression of the retro Michael reaction to afford an optically active cyclized product. The Baeyer-Villiger reaction of (R)-2-methoxymethyl-2-propylindanone in the presence of BF3·Et2O afforded the desired dihydrocoumarin.View full abstractDownload PDF (763K) -
Fumiko ABE, Mio HIROKAWA, Tatsuo YAMAUCHI, Keiichi HONDA, Nanao HAYASH ...1999 Volume 47 Issue 10 Pages 1384-1387
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFive new glycosides of 14, 15-seco- and 13, 14 : 14, 15-diseco-type pregnanes, including a new pregnane, 2α-hydroxyhirundigenin, were isolated, in addition to one known glycoside, cynatratoside B, from the roots of Tylophora tanakae MAXIM. Their structures were elucidated by spectral and chemical means.View full abstractDownload PDF (714K) -
Shigemi TAZAWA, Tsutomu WARASHINA, Tadataka NORO1999 Volume 47 Issue 10 Pages 1388-1392
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSeven new p-coumaric acid derivatives along with seventeen known compounds, including four flavonoids, one prenylated phenolic acid, four diterpenoic acids, one lignan, two p-coumaric acid esters and five cinnamic acid derivatives, were isolated from the ethyl acetate soluble fraction of 75% ethanol extract of Brazilian propolis. New compounds were elucidated as (E)-2, 3-dihydroconiferyl p-coumarate, (E)-3-{2, 3-dihydro-2-[2-[(E)-p-coumaroyloxy]-1-methylethyl]-5-benzofuranyl}-2-propenoic acid, (E)-4-(2, 3-dihydrocinnamoyloxy)cinnamic acid, (E)-3-(2, 2-dimethyl-3, 4-dihydro-3-hydroxy-2H-1-benzopyran-6-yl)-2-propenoic acid, (E)-3-[2, 3-dihydro-2-(1-methylethenyl)-5-benzofuranyl]-2-propenoic acid, (E)-3-[2, 3-dihydro-2-(1-methylethenyl)-7-prenyl-5-benzofuranyl]-2-propenoic acid and (E)-3-{3-[(E)-4-(2, 3-dihydrocinnamoyloxy)-3-methyl-2-butenyl]-4-hydroxy-5-prenylphenyl}-2-propenoic acid, on the basis of spectral evidence and chemical reaction. Five compounds : dihydrokaempferol (aromadendrin), 6-methoxykaempferol, 4-hydroxy-3-prenylbenzoic acid, plicatin B and capillartemisin A, were isolated from propolis for the first time.View full abstractDownload PDF (730K) -
Nobuyoshi AMISHIRO, Satoru NAGAMURA, Eiji KOBAYASHI, Akihiko OKAMOTO, ...1999 Volume 47 Issue 10 Pages 1393-1403
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA series of A-ring pyrrole compounds of duocarmycin bearing 5-membered heteroarylacryloyl groups (thienylacryloyl and pyrrolylacryloyl) and heteroarylcarbonyl groups were synthesized and evaluated for in vitro anticellular activity against HeLa S3 cells and in vivo antitumor activity against murine sarcoma 180 in mice. Most of the thienylacrylates displayed in vitro anticellular activity equivalent to 4'-methoxycinnamates. Among the 8-O-[(N-methylpiperazinyl)carbonyl] derivatives of methoxy-thienylacrylates, compound 11b, having 4'-methoxy-2'-thienylacryloyl as segment-B (Seg-B), showed remarkably potent antitumor activity and low peripheral blood toxicity in vivo, which were equal to those of 8-O-[(N-methylpiperazinyl)carbonyl] derivatives of 4'-methoxycinnamates, compared with the A-ring pyrrole derivatives having the trimethoxyindole skeleton in Seg-B. On the other hand, the 2'-pyrrolylacrylates having a double bond as spacer showed 102- to 103-fold stronger anticellular activity than 2'-pyrrolecarboxylates (IC50<0.3nM, 72 h-exposure). The 8-O-acetate and 8-O-[(N-methylpiperazinyl)carbonyl] derivatives of 2'-pyrrolylacrylates exhibited an antitumor effect at a lower dose compared with the 8-O-[(N-methylpiperazinyl)carbonyl] derivatives of 4'-methoxycinnamate (1j). Moreover, it was expected that the antitumor activity would be increased by the strength of the extra hydrogen bond formed between the nitrogen of the pyrrole amido group and DNA, owing to the increase of the number of N-methyl-2'-pyrrolecarboxamide units. However, 2'-pyrrolylacrylates having three N-methyl-2'-pyrrolecarboxamide units showed nearly equal antitumor activity to 2'-pyrrolylacrylates having only one N-methyl-2'-pyrrolecarboxamide unit.View full abstractDownload PDF (1638K) -
Akiko SEGAWA, Yukinori MIYAICHI, Tsuyoshi TOMIMORI, Fumiyuki KIUCHI, T ...1999 Volume 47 Issue 10 Pages 1404-1411
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSeven new phenolic compounds (8-14) including three ones having unique structure named didymocalyxins A (12), B (13) and C (14) have been isolated from the leaves of Didymocarpus leucocalyx, along with five known flavonoids (5-hydroxy-6, 7-dimethoxyflavanone, 5, 8-dihydroxy-6, 7-dimethoxyflavanone, 2', 6'-dihydroxy-3', 4'-dimethoxychalcone, 3'-hydroxy-2', 4', 5', 6'-tetramethoxychalcone and 2', 5'-dihydroxy-4'-methoxy-3', 6'-dioxochalcone) and two known anthraquinoids (physcion and catenarin). The structures of 8-14 were determined to be 3', 4-dihydroxy-2', 4', 5', 6'-tetramethoxychalcone (8), 5, 8-dihydroxy-6, 7-dimethoxyisoflavone (9), 1, 6, 8-trihydroxy-4-benzoyloxy-3-methylanthraquinone (10), (2S)-2, 3-dihydroxypropyl 1, 6, 8-trihydroxy-3-methyl-9, 10-dioxoanthracene-2-carboxylate (11), (±)-1, 4-dihydroxy-2, 3, 6, 7-tetramethoxy-10-phenyl-9, 10-dihydrocyclohepta[2, 1-b]4H-chromene-8, 11-dione (12), 3-((1E, 2E)-1-hydroxy-3-phenylprop-2-enylidene)-7-((2E)-3-phenylprop-2-enoyl)-6-hydroxy-4, 5-dimethoxybenzo[b]furan-2-one (13) and 2((1E)-2-phenylvinyl)-5, 6-dihydroxy-7, 8-dimethoxy-4H-pyrano[3, 2-d]benzo[b]furan-4-one (14) on the basis of chemical and spectroscopic evidence and X-ray analysis.View full abstractDownload PDF (1049K) -
Lai Wah CHAN, Jin Song HAO, Paul Wan Sia HENG1999 Volume 47 Issue 10 Pages 1412-1416
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAmong six grades of polyvinyl alcohol (PVA), PVA V (degree of hydrolysation 99.45%, molecular weight 140000-150000) and PVA VI (degree of hydrolysation 98-99%, molecular weight 85000-146000) were selected for combination with PVA I (degree of hydrolysation 99%, molecular weight 17300) to prepare composite films with different amounts of PVA I and film thickness. The permeability coefficients of diclofenac sodium through these films were determined and the elastic moduli measured. The permeability coefficients increased with the amount of PVA I in the PVA V-I films. Conversely, the presence of PVA I in the PVA VI-I films decreased the permeability of the composite films to diclofenac sodium. PVA VI-I films showed significantly higher permeability than PVA V-I films. These results indicated that PVA I content in the composite films was a critical factor, affecting the apparent solubility and/or swelling properties, and thereby permeability of the composite films. For PVA V-I films, the effect of PVA I on increasing solubility played a dominant role, but for PVA VI-I films, the effect of PVA I on decreasing swelling properties was a more important factor. Film thickness also influenced the permeability coefficients of diclofenac sodium through the composite films; film permeability decreasing with increasing film thickness. The addition of PVA I raised the elastic moduli of PVA VI-I film but showed minimal effect on PVA V-I films. Proper selection of PVA grades and weight ratio was the key element to successful preparation of PVA composite films with the desired characteristics.View full abstractDownload PDF (866K) -
Hironobu OGURA, Haruhito KOBAYASHI, Kiyoshi NAGAI, Tokiko NISHIDA, Tak ...1999 Volume 47 Issue 10 Pages 1417-1425
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS2-Aryl-1-azolyl-3-(substituted amino)-2-butanol derivatives I were prepared by ring-opening reaction of epoxides II with excess amine, and their antifungal activities were evaluated as topical agents. Azolyl-cyclic amine derivatives with a methylene group showed extremely strong activity with a broad spectrum in vitro. In general, anti-Trichophyton mentagrophytes activities of most of the topical antifungal agents are substantially reduced by addition of keratin (a major constituent of the keratinized tissue). However, the triazole derivative (2R, 3R)-2-(2, 4-difluorophenyl)-3-(4-methylenepiperidino)-1-(1H-1, 2, 4-triazol-1-yl)-2-butanol ((-)-40, KP-103) showed very little deactivation by addition of keratin. This biological characteristic of triazole derivative (-)-40 resulted in excellent therapeutic efficacy on dermatophytosis superior to that of the corresponding imidazole derivative ((-)-41).View full abstractDownload PDF (1058K) -
Haruhiro FUJIMOTO, Toshiyuki FUJIMAKI, Emi OKUYAMA, Mikio YAMAZAKI1999 Volume 47 Issue 10 Pages 1426-1432
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFractionation guided by the immunosuppressive activity of the defatted AcOEt extract of an Ascomycete, Microascus tardifaciens, afforded eight constituents, questin (emodin 8-O-methylether) (1), rubrocristin (2), 5, 7-dihydroxy-4-methylphthalide (3), cladosporin (asperentin) (4), cladosporin 8-O-methylether (5), tardioxopiperazine A [cyclo-L-alanyl-5-isopentenyl-2-(1', 1'-dimethylallyl)-L-tryptophan] (6), tardioxopiperazine B [cyclo-L-alanyl-7-isopentenyl-2-(1', 1'-dimethylallyl)-L-tryptophan] (7), and asperflavin (8), among which 6 and 7 were new compounds. Compounds 1 and 2 showed considerably high immunosuppressive activity, 6 was moderate and, 3, 4, 5, 7 and 8 showed low activity.View full abstractDownload PDF (916K) -
Yoshio TAKEDA, Yuuko KIBA, Toshiya MASUDA, Hideaki OTSUKA, Gisho HONDA ...1999 Volume 47 Issue 10 Pages 1433-1435
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFrom the aerial parts of Nepeta racemosa, two new iridoid glucosides, nepetaracemosides A and B, which are related to nepetalactone and dehydronepetalactone, were isolated. The structures of the new compounds were elucidated by spectral and chemical analyses.View full abstractDownload PDF (552K) -
Emika OHKOSHI, Mitsuko MAKINO, Yasuo FUJIMOTO1999 Volume 47 Issue 10 Pages 1436-1438
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo novel norhumulene-type sesquiterpenes, named mikaniahumulene I (1) and II (2) were isolated along with nine known compounds, seven kaurenic acid-type diterpenes (3-9), a coumarin (10) and a flavone (11), from the aerial parts of Mikania hirsutissima DC (Compositae). The structures of new norhumulenes were determined by spectroscopic means. The cytotoxic activities of isolated compounds against leukemia cells (L 1210) were investigated; among the isolated compounds, 1, 5, 8, and 11 showed relatively strong cytotoxicity.View full abstractDownload PDF (465K) -
Reductive Dimerization of 2-Substituted Cyclopropane-1, 1-dicarboxylates Using Samarium(II) DiiodideMasayuki YAMASHITA, Kazunori OKUYAMA, Takashi OHHARA, Ikuo KAWASAKI, Y ...1999 Volume 47 Issue 10 Pages 1439-1443
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIn the presence of samarium diiodide, 2-aryl and 2-heteroaryl cyclopropane-1, 1-dicarboxylic esters were readily dimerized to give 3, 4-disubstituted 1, 1, 6, 6-hexanetetracarboxylic esters as diastereomeric mixtures in moderate to good yields. The diastereomeric mixtures were separated by preparative HPLC and stereo-chemistries of the isolated meso and racemic compounds were determined on the basis of HPLC analysis on chiral stationary phases. Between the 1H-NMR spectra of the separated diastereomers, the characteristic differences in the chemical shifts of the C2-H (C5-H) signals were observed and explained based on the MOPAC calculation.View full abstractDownload PDF (794K) -
Toshiko SATAKE, Kohei KAMIYA, Yasuhisa SAIKI, Takao HAMA, Yasuo FUJIMO ...1999 Volume 47 Issue 10 Pages 1444-1447
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThree new compounds; 4'-O-β-D-glucopyranosyl rosmarinic acid (2), 4, 4'-O-di-β-D-glucopyranosyl rosmarinic acid(3) and 2R-O-(4'-O-β-D-glucopyranosyl caffeoyl)-3-(4-hydroxyphenyl) lactic acid named as 4'-O-β-D-glucopyranosyl isorinic acid (4) were isolated together with rosmarinic acid (1) from the fruit of Helicteres isora L. (Sterculiaceae), an Indonesian medicinal plant. The structures of these compounds, including the absolute stereochemistry of 4, were elucidated by spectroscopic analysis and chemical means. Compound 3 had greater scavenging activity against superoxide anion produced with xanthine and xanthine oxidase (XOD) than rosmarinic acid (1).View full abstractDownload PDF (693K) -
Junichi KITAJIMA, Toru ISHIKAWA, Yasuko TANAKA, Yoshiteru IDA1999 Volume 47 Issue 10 Pages 1448-1450
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFrom the water-soluble portion of the methanol extract of the herbal medicine fennel, a new chromanone glycoside and a new phenylethanoid glycoside were isolated, and their structures were determined by spectral methods. An optical isomeric mixture of threo-epoxyanethole was obtained from the ether-soluble portion, and it was considered to be an auto-oxidation product of trans-anethole.View full abstractDownload PDF (548K) -
Tatsuya ISHIKAWA, Yoshiteru WATANABE, Naoki UTOGUCHI, Mitsuo MATSUMOTO1999 Volume 47 Issue 10 Pages 1451-1454
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe aim of this study was to prepare, using taste-masked granules, tablets which can rapidly disintegrate in saliva (rapidly disintegrating tablet), of drugs with bitter taste (pirenzepine HCl or oxybutynin HCl). The taste-masked granules were prepared using aminoalkyl methacrylate copolymers (Eudragit E-100[○!R]) by the extrusion method. None of the drugs dissolved from the granules (% of dissolved, <5%) even at 480 min at pH 6.8 in the dissolution test. However, the drugs dissolved rapidly in the medium at pH 1.2 in the dissolution test. Rapidly disintegrating tablets were prepared using the prepared taste-masked granules, and a mixture of excipients consisting of crystalline cellulose (Avicel PH-102[○!R]) and low-substituted hydroxypropylcellulose (L-HPC, LH-11[○!R]). The granules and excipients were mixed well (mixing ratio by weight, crystalline cellulose : L-HPC=8 : 2) with 1% magnesium stearate, and subsequently compressed at 500-1500 kgf in a single-punch tableting machine. The prepared tablets (compressed at 500 kgf) containing the taste-masked granules have sufficient strength (the crusing strength : oxybutynin tablet, 3.5 kg; pirenzepine tablet, 2.2 kg), and a rapid disintegration time (within 20 s) was observed in the saliva of healthy volunteers. None of the volunteers felt any bitter taste after the disintegration of the tablet which contained the taste-masked granules. We confirmed that the rapidly disintegrating tablets can be prepared using these taste-masked granules and excipients which are commonly used in tablet preparation.View full abstractDownload PDF (656K) -
Hisafumi IKEDA, Kaoru FUJI, Kiyoshi TANAKA, Yasuyoshi ISO, Fumio YONED ...1999 Volume 47 Issue 10 Pages 1455-1463
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAiming at the creation of functionalized antisense DNA oligomers possessing site-selective DNA cleaving activity, viologen and a related compound, diazapyrenium dication (DAP2+), were selected and introduced into oligodeoxyribonucleotides as a functionalized molecule. The conjugation of these functionalized molecules with DNA proceeded smoothly by using standard H-phosphonate chemistry. A part of the DAP2+ -tethered DNA oligomers was synthesized by a combination of solid support method and liquid phase technique. Viologen-tethered DNA oligomers showed no significant activity toward DNA cleavage in spite of their characteristic ESR spectra. On the other hand, it was observed that the DAP2+-tethered DNA oligomers formed more stable duplexes with their complementary strands than the corresponding wild type, and these molecules effectively cleaved the complementary strands at the specific site of 2-3 bases away from the modified phosphoramidate linkage. The effect of position and length of the linker arm on the selectivity in the cleavage reaction was also investigated, and it was found that introduction at the 3'- or 5'-end phosphate site is more favorable, probably due to duplex stabilization.View full abstractDownload PDF (1321K) -
Taisuke ITAYA, Tae KANAI, Shin-ichi OHYAMA, Yoshihisa SHIRASAKI, Nobuh ...1999 Volume 47 Issue 10 Pages 1464-1472
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS1-Benzyl-4, 6-dimethyl-4, 9-dihydro-1H-imidazo[1, 2-α]purin-9-one bearing an alkyl, a 1-alkenyl, a hydroxymethyl, a methoxymethyl, or a formyl group at the 7-position (3a-e) underwent rearrangement through fission and recyclization of the pyrimidine ring, attaining equilibrium with the corresponding positional isomer 4a-e in MeONa-MeOH at 25°C, whereas 7-methoxycarbonyl and 7-halogeno compounds 3f-i were irreversibly converted into the rearranged products 4f-i under identical conditions. The position of equilibrium appears to be affected by the electronic factor of the substitutent rather than the steric one. The pseudo-first-order rate constants measured for the reactions of 3a, b, d, f-i suggest that the reaction is accelerated by the electron-withdrawing substituent. However, the reactions of this series of compounds do not always obey the Hammett equation.On the other hand, a linear free energy relationship (ρ=+3.2) was observed for the rates of rearrangement of a 6-demethyl series of compounds 9a, b, d, f, g, when σ0P values were employed. The deviations from this relationship for the reactions with the 7-hydroxymethyl compound 9c and the 7-carbamoyl compound 9e are explicable in terms of the accelerative effect through intramolecular hydrogen bonding with the carbonyl oxygen at the 9-position.View full abstractDownload PDF (1544K) -
Emi OKUYAMA, Masayuki HOMMA, Yoko SATOH, Haruhiro FUJIMOTO, Masami ISH ...1999 Volume 47 Issue 10 Pages 1473-1476
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFrom the extract of a Malaysian herbal medicine, Lemuni Hitam (Diospyros sp.), which exhibited monoamine oxidase (MAO) inhibition, three new naphthoquinone and/or naphthalene dimers (lemuninols A-C, 1-3) were isolated together with 4, 6-dihydroxy-5-methoxy-2-methyl-naphthalene (8) and six known monomers (4-7, 9 and 10). The structures were determined by spectroscopic methods including 2D-NMR techniques. Among them, lemuninol A showed 45% inhibition of MAO (mouse liver ) at 5.0×10-6 g/ml, and lemuninols B and C and a naphthoquinone (9) indicated weak activity. Some related quinones were also tested for their MAO inhibitory activities.View full abstractDownload PDF (675K) -
Kuniharu SUZUMURA, Mikiko YASUHARA, Hiroshi NARITA1999 Volume 47 Issue 10 Pages 1477-1480
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWe investigated the in vitro superoxide anion scavenging activities of fluvastatin and its metabolites. Fluvastatin showed dose-dependent superoxide anion scavenging activity in the NADH/phenazine methosulphate (PMS)/nitroblue tetrazolium (NBT) system, and the effect was as potent as the reference antioxidant, trolox, which is a water-soluble α-tocopherol derivative. The superoxide anion scavenging activities of the major metabolites of fluvastatin (M2, M3, M4, M7) were also determined in this system. All of these metabolites showed the activity. In particular, M2 and M3, which possess a phenolic hydroxyl group at the 5 or 6-position of the indole moiety, respectively, showed 3 times stronger activities than that of fluvastatin. Further, we also determined the effects of fluvastatin, M2 and M3 on phorbol myristate acetate (PMA)-induced superoxide anion generation in human peripheral blood polymorphonuclear leukocytes (PMN). The compounds tested also showed a depressing effect on the amount of superoxide anion in this system. We suggest that fluvastatin and its metabolites have the potential to protect cells or lipids from oxidative modification mediated by superoxide anion.View full abstractDownload PDF (663K) -
Naohiko MORISHIMA, Yoko MORI1999 Volume 47 Issue 10 Pages 1481-1483
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe tritylation reaction of 1, 2-O-isopropylidene-α-D-glucofuranose with 2.4 molar amounts of trityl chloride in pyridine at 70°C for 20 h gave the 5, 6-di-O-trityl derivative in 50% yield as the major product, whereas the reaction at 115°C mainly gave the 3, 6-di-O-trityl derivative (26% yield) along with the 6-O-trityl derivative (48% yield). The fact that the yield of the 5, 6-di-O-trityl derivative at 115°C decreased after 1 h and was 12% at 20 h is due to the redistribution of trityl groups including detritylation assisted by pyridinium chloride. It was found that tritylation of the primary hydroxyl group at C-6 was almost completed within 10 min at 115°C.View full abstractDownload PDF (539K) -
Si-Hyung PARK, Sei Ryang OH, Keum Young JUNG, Im Seon LEE, Kyung Seop ...1999 Volume 47 Issue 10 Pages 1484-1486
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSDuring a search for biologically active compounds from traditional medicines, a crude extract of Persicaria lapathifolia was found to have anti-complement activity. Bioassay-guided chromatographic separation of the active constituents led to the isolation of a new acylated kaempferol glycoside (1) and three known acylated quercetin glycosides (2-4). The structures of compounds 1-4 were characterized as kaempferol 3-O-β-D-(6"-p-hydroxybenzoyl)-galactopyranoside, quercetin 3-O-β-D-(6"-feruloyl)-galactopyranoside, quercetin 3-O-β-D-(2"-galloyl)-rhamnopyranoside and quercetin 3-O-β-D-(2"-galloyl)-glucopyranoside, respectively. Compounds 1-4 showed strong anti-complement activity (IC50 values of 4.3, 9.7, 3.9 and 7.6×10-5M, respectively) on the classical pathway of the complement. On the other hand, six isolated flavonol glycosides (5-10) did not show any activity on this system.View full abstractDownload PDF (484K) -
Tsuyoshi IKEDA, Yuko OGAWA, Toshihiro NOHARA1999 Volume 47 Issue 10 Pages 1487-1488
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new triterpenoid named cuneataol was isolated from the fruit of Crataegus cuneata SIEB. et ZUCC. On the basis of spectroscopic analysis, the structure was elucidated as 2, 25-epoxy-2α, 3β, 19α-trihydroxyurs-12-en-28-oic acid.View full abstractDownload PDF (398K) -
Stanislaw WIEJAK, Elzbieta MASIUKIEWICZ, Barbara RZESZOTARSKA1999 Volume 47 Issue 10 Pages 1489-1490
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIn the search for a practical route to lysine diurethane derivatives useful for peptide synthesis, we elaborated the synthesis of Nε-tert-butoxycarbonyl-L-lysine copper(II) complex (1). This served as substrate for obtaining Nε-tert-butoxycarbonyl-L-lysine (2), Nα-benzyloxycarbonyl-Nε-tert-butoxycarbonyl-L-lysine dicyclohexylamine salt (3) and Nα-(9-fluorenyl)methoxycarbonyl-Nε-tert-butoxycarbonyl-L-lysine (4).View full abstractDownload PDF (478K) -
Chihiro ITO, Yuichi KONDO, Nijsiri RUANGRUNGSI, Hiroshi FURUKAWA1999 Volume 47 Issue 10 Pages 1491-1493
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo new quinazoline alkaloids, glycozolone-A (1) and -B (2), and anthranilylamide, glycoamide-A (3) and -B (4) were isolated from leaves of Glycosmis cochinchinensis [LOUR.] PIERRE (Rutaceae) collected in Thailand. Structures were characterized on the basis of spectroscopic methods.View full abstractDownload PDF (535K) -
Kyoko KOFUJI, Kaori SHIBATA, Yoshifumi MURATA, Etsuko MIYAMOTO, Susumu ...1999 Volume 47 Issue 10 Pages 1494-1496
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSChitosan (CS) gel beads containing drug could be prepared in amino acid solutions of pH about 9, despite the requirement for a pH above 12 for gelation in water. This phenomenon was observed not only in amino acid solutions but also in solutions of compounds having amino groups. A solute concentration of more than 10% was required for preparation of gel beads at pH 9. Gelation of the CS beads required about 25 to 40 min, depending on the species of amino acid. Lidocaine hydrochloride (LC) as a model drug was retained in the beads to about 20 to 35% of the theoretical total amount, despite being a water-soluble drug. The release of LC from the CS gel beads was prolonged. The release pattern was not affected by the species of amino acid or CS, or the preparation time.View full abstractDownload PDF (494K) -
Mitsuhiro YOSHIMATSU, Sayaka KINOSHITA, Tomomi SUGIMOTO1999 Volume 47 Issue 10 Pages 1497-1500
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS2-Sulfonyl-1-buten-3-yne (2-sulfonyl enyne) 7 was obtained via the Pd-catalyzed cross-coupling reactions of β-bromo enol ethers 3 and 4 and successive oxidation with m-chloroperbenzoic acid.View full abstractDownload PDF (662K) -
Satendra SINGH, Kwasi S. AVOR, Buddy POUW, Thomas W. SEALE, Garo P. BA ...1999 Volume 47 Issue 10 Pages 1501-1505
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAn efficient synthesis of isoxazole containing isosteres of epibatidine is described. The synthesis proceeded from N-tert-butoxycarbonyl (Boc)-exo-2-(methoxycarbonyl)-7-azabicyclo[2.2.1]heptane (9). Compound 9 was reacted with the dilithium salt of an appropriately substituted oxime in tetrahydrofuran (THF). Cyclodehydration of the resultant β-keto oxime and deprotection of the N-Boc group in 5N aqueous HCl afforded the isoxazole containing isosteres of epibatidine (6-8). The binding affinities of these compounds were determined at the nicotinic acetylcholine receptor for the displacement of [3H]cytisine. The unsubstituted isoxazole containing isostere (6) showed the lower binding potency compared to the 3'-methylisoxazole isostere (7). Substitution with a phenyl group at the 3'-position of the isoxazole significantly reduced the binding potency. The in vivo toxicological studies of these analogs were also performed. The LD50 of the analogs ranged in the order : Me>H>Ph.View full abstractDownload PDF (882K) -
Yusuke SASAKI, Takuya SUTO, Akihiro AMBO, Hidekazu OUCHI, Yutaka YAMAM ...1999 Volume 47 Issue 10 Pages 1506-1509
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTo understand the effect of the replacement of Tyr residue at position 1 in opioid peptides by 2, 6-dimethyl-Tyr (Dmt) on the biological property, chiral (D or L) Dmt1 analogs of Leu-enkephalin (Enk) and Tyr-D-Arg-Phe-βAla-NH2 (YRFB) were synthesized and their enzymatic stabilities, in vitro bioactivities and receptor binding affinities compared with those of parent peptides. [L-Dmt1]Enk (1) exhibited 4-fold higher stability against aminopeptidase-M and possessed dramatically increased activities in guinea pig ilium (GPI) (187-fold) and mouse vas deferens (MVD) (131-fold) assays, and in rat brain receptor binding assays (356-fold at μ receptor and 46-fold at δ receptor) as compared to Enk. [L-Dmt1]YRFB (3) also exhibited increased activties in GPI (46-fold) and MVD (177-fold) assays, and in the binding assays (69-fold at μ receptor and 341-fold at δ receptor) as compared to the parent peptide. [D-Dmt1]Enk (2) and [D-Dmt1]YRFB (4) exhibited activities with diminished or lesser potency than the parent peptide in all assays. These results indicate that there is a tendency for μ affinity to be enhanced more than δ affinity with introduction of L-Dmt into δ ligand peptide (Enk), and for δ affinity to be enhanced more than μ affinity in case of μ ligand peptide (YRFB), resulting in reduced receptor selectivities at the receptors.View full abstractDownload PDF (634K) -
Jose H. ISAZA M, Hideyuki ITO, Takashi YOSHIDA1999 Volume 47 Issue 10 Pages 1510-1511
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new acylated flavonol glycoside, called monochaetin, was isolated along with three known flavonoids from the leaves of Monochaetum multiflorum, and its structure was characterized as a novel di-hyperin ester of 3, 3', 4, 4'-tetrahydroxy-μ-truxinic acid on the basis of chemical methods and 2D-NMR spectral analyses.View full abstractDownload PDF (403K) -
Osamu OHMORI, Hiromitsu TAKAYAMA, Mariko KITAJIMA, Norio AIMI1999 Volume 47 Issue 10 Pages 1512-1513
Published: October 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe novel structure of neoalangiside, a new tetrahydroisoquinoline-monoterpene glucoside carrying oxygen functions at the unusual C1 and C2 positions, was confirmed by chemical synthesis starting from isovanillin and secologanin.View full abstractDownload PDF (403K)
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