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Volume 50, Issue 4
Displaying 1-26 of 26 articles from this issue
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Regular Articles
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Satoru Goto, Kyoko Masuda, Miyuki Miura, Keiko Kanazawa, Miki Sasaki, ...Article type: Regular Article
Subject area: [not specified]
2002 Volume 50 Issue 4 Pages 445-449
Published: 2002
Released on J-STAGE: July 10, 2002
JOURNAL FREE ACCESSWe measured the affinity of more than 20 sugars with concanavalin A (ConA) by an optical biosensor (surface plasmon resonance sensor) using asialofetuin (ASF) as an immobilized binding partner of ConA. We determined kinetic parameters of the effects of sugars on the dissociation of ConA from ASF quantitatively, and the structural requirements of the functional groups of sugars for binding with ConA. We found that the affinity of ConA for sugars is dependent on its conformation induced by interaction with the binding partner. In addition, the results showed that optical biosensor system is well mimics the interaction of ConA with sugars in biomembrane.View full abstractDownload PDF (70K) -
Sang Yoon Choi, Sanghee Kim, Hocheol Kim, Kyoungho Suk, Jae Sung Hwang ...Article type: Regular Article
Subject area: [not specified]
2002 Volume 50 Issue 4 Pages 450-452
Published: 2002
Released on J-STAGE: July 10, 2002
JOURNAL FREE ACCESSThe current study was carried out to investigate in vitro the effects of (4-methoxy-benzylidene)-(3-methoxy-phenyl)-amine on melanin biosynthesis which is closely related to hyper-pigmentation. (4-Methoxy-benzylidene)-(3-methoxy-phenyl)-amine, a nitrogen analog of stilbene, was synthesized by a single step process. This compound inhibited the tyrosinase activity, which converts dopa to dopachrome in the biosynthetic process of melanin, and showed a UV-blocking effect at UV-B band. The compound also exhibited SOD-like activity, which is involved in the protection against auto-oxidation and inhibited melanin production in melan-a cell line. Our results suggest the possibility that (4-methoxy-benzylidene)-(3-methoxy-phenyl)-amine might be used as a skin whitening agent.View full abstractDownload PDF (52K) -
Hiroyuki Naito, Satoru Ohsuki, Masamichi Sugimori, Ryo Atsumi, Megumi ...Article type: Regular Article
Subject area: [not specified]
2002 Volume 50 Issue 4 Pages 453-462
Published: 2002
Released on J-STAGE: July 10, 2002
JOURNAL FREE ACCESSA series of novel 3-substituted-1-[5-methyl-1-(2-pyrimidinyl)-4-pyrazolyl]-1-trans-propenes in order to improve the in vitro and in vivo activity of our prototype 3-[4-(3-chlorophenyl)-1-piperazinyl]-1-[5-methyl-1-(2-pyrimidinyl)-4-pyrazolyl]-1-trans-propene (2) were synthesized and evaluated by assays of growth inhibition against several tumor cell lines in vitro and antitumor activity against some tumor models when dosed both intraperitoneally and orally in vivo. Compounds 7a and 7e, the 3,5-difluorophenyl and 3,5-dichlorophenyl analogues of 2, respectively, showed significantly more potent cytotoxicity than 2 in vitro and potent antitumor activities without causing decrease of body temperature related to side effects.View full abstractDownload PDF (112K) -
Danuta Branowska, Stanislaw Ostrowski, Andrzej RykowskiArticle type: Regular Article
Subject area: [not specified]
2002 Volume 50 Issue 4 Pages 463-466
Published: 2002
Released on J-STAGE: July 10, 2002
JOURNAL FREE ACCESSSynthesis of 2,3- and 3,4-cyclopentenopyridines, 5,6,7,8-tetrahydroquinolines and 5,6,7,8-tetrahydroisoquinolines from 1,2,4-triazine derivatives is reported. Introduction of an α-functionalized methyl substituent (e.g. arylsulphonyl, sulphonamide, sulphonic acid ester) into position 3- or 6- of triazines by vicarious nucleophilic substitution of hydrogen and subsequent alkylation with alkyl iodides bearing an acetylenic function in terminal position afforded valuable intermediates for intramolecular Diels–Alder reaction with inverse electron demand. When heated at higher temperature, these triazine derivatives gave the Diels–Alder cycloadducts, which, after spontaneous extrusion of nitrogen moiety, led to a variety of functionalized cycloalkenopyridine derivatives.View full abstractDownload PDF (66K) -
Chie Honda, Kiyoko Suwa, Shizuyo Takeyama, Wasuke KamisakoArticle type: Regular Article
Subject area: [not specified]
2002 Volume 50 Issue 4 Pages 467-474
Published: 2002
Released on J-STAGE: July 10, 2002
JOURNAL FREE ACCESSRelative populations of S-form (D–E rings: boat–boat form) and F-form (D–E rings: chair–chair form) conformers, in equilibrium in CDCl3 solutions, of 20 derivatives (2—21) of bryonolic acid (D:C-friedoolean-8-en-3β-ol-29-oic acid) (1) were calculated from NMR spectral data (J-values and chemical shifts), with the aid of molecular mechanic calculation using a MM2/CONFLEX program system. The principal deciding factor of the population ratio was found to be whether the functionality at C-29 is trigonal or tetrahedral; the S-form : F-form was 0 : 100—32 : 68 for the “trigonal” type and 48 : 52—100 : 0 for the “tetrahedral.” The reliability of the results is discussed.View full abstractDownload PDF (100K) -
Akiko Ohno, Masato Shimizu, Sachiko YamadaArticle type: Regular Article
Subject area: [not specified]
2002 Volume 50 Issue 4 Pages 475-483
Published: 2002
Released on J-STAGE: July 10, 2002
JOURNAL FREE ACCESSTo investigate vitamin D conformation, specifically the A-ring and seco-B ring parts, in its complex with the vitamin D receptor (VDR), we have previously suggested the use of 19F-NMR spectroscopy and have synthesized three fluorovitamin D derivatives to be used for the study, 4,4-difluoro-1α,25-dihydroxyvitamin D3 [4,4-F2-1,25-(OH)2D3,2a], and (10Z)- and (10E)-19-fluoro-1α,25-dihydroxyvitamin D3 [19-F-1,25-(OH)2D3,3a,4a]. In this paper, we examined the 19F-NMR spectra of these and related fluorovitamin D compounds in detail. In the low temperature 19F-NMR spectra, we observed two well-separated rigid conformations of 2a (51 : 49) and 4a (84 : 16), while only one conformation was detected with 3a. The two observed conformers of 2a and 4a were respectively assigned to the known α- and β-conformers formed by the flipping of the A-ring where the C(19) exocyclic methylene points to the α- and β-faces. The single conformation observed for 3a was assigned to the α-conformer. We detected no other conformation in the 19F-NMR of all vitamin D compounds examined. The effect of solvents on the 19F chemical shifts of fluorovitamin D compounds was found to be small (less than 6.3 ppm). This was much smaller than the difference between the two A-ring conformers (13—30 ppm). Using the dynamic 1H-NMR studies of fluorovitamin D compounds, we determined the free energy of activation for the interconversion between the two conformations of 2a (9.9 kcal/mol) and 4a (10.8, 11.5 kcal/mol). Introduction of the 1α-hydroxyl group raised the activation energy about 1 kcal/mol. The affinity for VDR was evaluated, and the relative potency of 2a, 3a and 4a was found to be 1%, 8% and 9%, respectively, of that of 1, 25-(OH)2D3 (1). Though the affinity for VDR was considerably reduced in these compounds, the ability to activate gene transcription was similar and remained in the range 30—50% of the effect of 1. This biological information in combination with the NMR properties indicates that 2a and 4a are promising probes for studying the VDR-bound A-ring conformation of vitamin D.View full abstractDownload PDF (107K) -
Takeshi Koike, Naoki TakeuchiArticle type: Regular Article
Subject area: [not specified]
2002 Volume 50 Issue 4 Pages 484-488
Published: 2002
Released on J-STAGE: July 10, 2002
JOURNAL FREE ACCESSThe reactions of sec-aminodienyl esters 3 with acetylacetone (4) afforded N-alkyl 3-acetyl-4-methoxycarbonylmethyl-2-methyl-1,4-dihydropyridines 5 and enamines 6, providing a new azaelectrocyclization reaction.View full abstractDownload PDF (60K) -
Takashi Ishizu, Hendig Winarno, Etsuji Tsujino, Tetsuo Morita, Hirotak ...Article type: Regular Article
Subject area: [not specified]
2002 Volume 50 Issue 4 Pages 489-492
Published: 2002
Released on J-STAGE: July 10, 2002
JOURNAL FREE ACCESSA complex of perseitol (D-glycero-D-galacto-heptitol) and K+ ions in a molar ratio of 20 : 1 was isolated from the leaves of Scurrula fusca (Loranthaceae), which has been traditionally used for the treatment of cancer in Sulawesi Island, Indonesia. The stereochemical structure of the complex in H2O solution has been elucidated by use of several kinds of NMR techniques. Furthermore, it has been found that the complex exhibits a potent inhibitory effect on [3H]-leucine incorporation for protein synthesis in Ehrlich ascites tumor cells in mice.View full abstractDownload PDF (68K) -
Koichi Machida, Atsuko Kaneko, Tomokazu Hosogai, Rie Kakuda, Yasunori ...Article type: Regular Article
Subject area: [not specified]
2002 Volume 50 Issue 4 Pages 493-497
Published: 2002
Released on J-STAGE: July 10, 2002
JOURNAL FREE ACCESSFive new iridoid glycosides, (8Z)-ligstroside (1), (8Z)-nüzhenide (3), 6′-O-α-D-glucopyranosylsyringopicroside (4), 3′-O-β-D-glucopyranosylsyringopicroside (5) and 4′-O-β-D-glucopyranosylsyringopicroside (6) were isolated, together with a known one, (8E)-nüzhenide (2), from the leaves of Syringa reticulata. Their structures were established on the basis of chemical and spectral data. Compounds 1 and 3 are the first findings of a (8Z)-oleoside-type secoiridoid. Compound 4 is the first naturally occurring iridoid di-glycoside having an isomaltose.View full abstractDownload PDF (82K) -
Yen-Cheng Li, Yueh-Hsiung KuoArticle type: Regular Article
Subject area: [not specified]
2002 Volume 50 Issue 4 Pages 498-500
Published: 2002
Released on J-STAGE: July 10, 2002
JOURNAL FREE ACCESSFive new labdane-type diterpenes, 12β,19-dihydroxymanoyl oxide (1), 8(17),13-labdadien-12,15-olid-19-oic acid (2), 12,15-epoxy-8(17),13-labdadien-18-oic acid (3), 8α-hydroxy-11E,13Z-labdadien-15-al (4), and (13R)-13-hydroxy-8(17),11E,14-labdatrien-18-oic acid (5) were isolated from the wood of Cunninghamia konishii. Their structures were elucidated by two-dimensional NMR spectroscopy.View full abstractDownload PDF (54K) -
Toru Ishikawa, Masato Kudo, Junichi KitajimaArticle type: Regular Article
Subject area: [not specified]
2002 Volume 50 Issue 4 Pages 501-507
Published: 2002
Released on J-STAGE: July 10, 2002
JOURNAL FREE ACCESSFrom the water-soluble portion of the methanol extract of dill (fruit of Anethum graveolens L.), which has been used as a spice and medicine, thirty-three compounds, including a new monoterpenoid, six new monoterpenoid glycosides, a new aromatic compound glucoside and a new alkyl glucoside were obtained. Their structures were clarified by spectral investigation.View full abstractDownload PDF (95K) -
Masao Toyota, Yasushi Oiso, Yoshinori AsakawaArticle type: Regular Article
Subject area: [not specified]
2002 Volume 50 Issue 4 Pages 508-514
Published: 2002
Released on J-STAGE: July 10, 2002
JOURNAL FREE ACCESSThirteen glycosides and methyl (3R,5R)-5-hydroxy-(β-D-glucopyranosyloxy)-hexanoate were newly isolated from the Japanese fern Hymenophyllum barbatum, although our previous work revealed the isolation of hemiterpene glycosides, hymenosides A—J, from the same species. The structures of the newly isolated glycosides were elucidated by extensive two-dimensional (2D) NMR and/or chemical evidence. The structures of those aglycones were divided into four types, 2-methyl-but-2-ene-1,4-diol, 2-hydroxymethyl-but-2-ene-1,4-diol, 2-methylene-butane-1,3,4-triol, and 3-hydroxy-5-hexanolide. The sugar moieties, which were acylated by phenylacetic acid derivatives, were also established by chemical and spectroscopic methods. Eight glucosides of the isolated compounds in the present investigation had a bitter or weakly pungent taste. It is clear that a phenylacetyl group attached to glucose or allose as an ester is necessary for the bitter taste.View full abstractDownload PDF (85K) -
Itrat Anis, Saeed Ahmed, Abdul Malik, Amsha Yasin, M. Iqbal ChoudaryArticle type: Regular Article
Subject area: [not specified]
2002 Volume 50 Issue 4 Pages 515-518
Published: 2002
Released on J-STAGE: July 10, 2002
JOURNAL FREE ACCESSIsoprenylated flavonoids 5,7-dihydroxy-3′-(2-hydroxy-3-methyl-3-butenyl)-3,6,4′-trimethoxyflavone (1), 3,7-dihydroxy-3′-(2-hydroxy-3-methyl-3-butenyl)-5,6,4′-trimethoxyflavone (2) and an isoprenylated acetophenone derivative (3) have been isolated from Duranta repens along with known compounds, 5-hydroxy-3,6,7,4′-tetramethoxyflavone (4), rosenonolactone (5), 6,7-dimethoxycoumarin (6), 5α,8α-epidioxyergosta-6,22-dien-3β-ol (7) and 5α,8α-epidioxyergosta-6,9(11),22-trien-3β-ol (8), isolated for the first time from this species. Their structures and the relative configuration were determined by spectroscopic methods (1H- and 13C-NMR, IR, UV and MS) and two-dimensional (2D)-NMR experiments. The compounds 1—5 showed inhibitory activity against prolyl endopeptidase while 4 and 5 were also active against thrombin.View full abstractDownload PDF (70K) -
Takashi Harayama, Toshihiko Akiyama, Yuichiro Nakano, Hiromi Nishioka, ...Article type: Regular Article
Subject area: [not specified]
2002 Volume 50 Issue 4 Pages 519-522
Published: 2002
Released on J-STAGE: July 10, 2002
JOURNAL FREE ACCESSA palladium-assisted coupling reaction of aryl triflate with arene was investigated, and a novel Pd reagent prepared from equimolar Pd(OAc)2, 1,3-Bis[diphenylphosphino]propane (DPPP), and Bu3P was developed. This method is useful for intramolecular biaryl coupling reactions, not only between aryl triflate and arene (triflate-amide), but also between aryl halide and arene (halo-amide).View full abstractDownload PDF (53K) -
Sahar El-Mekkawy, Meselhy Ragab Meselhy, Atef Abdel-Monem Abdel-Hafez, ...Article type: Regular Article
Subject area: [not specified]
2002 Volume 50 Issue 4 Pages 523-529
Published: 2002
Released on J-STAGE: July 10, 2002
JOURNAL FREE ACCESSForty-eight derivatives of phorbol (9) and isophorbol (14) were evaluated for their inhibition of human immunodeficiency virus (HIV)-1 induced cytopathic effects (CPE) on MT-4 cells, as well as their activation of protein kinase C (PKC), as indices of anti-HIV-1 and tumor promoting activities, respectively. Of these compounds, the most potent inhibition of CPE was observed in 12-O-tetradecanoylphorbol 13-acetate (8) and 12-O-acetylphorbol 13-decanoate (6). The former also showed the strongest PKC activation activity, while the latter showed no activity at 10 ng/ml. Both activities were generally observed in those phorbol derivatives with an A/B trans configuration, but not in the isophorbol derivatives with an A/B cis configuration. Acetylation of 20-OH in the phorbol derivatives significantly reduced the inhibition of CPE, as shown in 12-O-, 20-O-diacetylphorbol 13-decanoate (6a) (IC100=15.6 μg/ml) vs. compound 6 (IC100=0.0076 μg/ml), and 12-O-tetradecanoylphorbol 13,20-diacetate (8a) (IC100=15.6 μg/ml) vs. 12-O-tetradecanoylphorbol 13-acetate (8) (IC100=0.00048 μg/ml), except in the case of 12-O-decanoylphorbol 13-(2-methylbutyrate) (4) and phorbol 12,13-diacetate (9c). The reduction of a carbonyl group at C-3 abruptly reduced the inhibition of CPE, as observed in 3β-hydroxyphorbol 12,13,20-triacetate (9f) (IC100=500 μg/ml) vs. phorbol 12,13,20-triacetate (9d) (IC100=62.5 μg/ml). Although 8 was equipotent in the inhibition of CPE, and activation of PKC, both activities were abruptly decreased by the acetylation of 20-OH and methylation of 4-OH [as in 8a and 4-O-methyl-12-O-tetradecanoylphorbol 13,20-diacetate (8b), respectively]. On the other hand, its positional isomer (12-O-acetylphorbol 13-tetradecanoate (8c) showed neither activities. The removal of a long acyl group in 8 led to a substantial loss of both activities, as shown in phorbol 13-acetate (9b). Of the 12-O-acetyl-13-O-acylphorbol derivatives, the highest inhibition of CPE was observed in 6, which has a dodecanoyl residue at C-13. Both an increase and decrease in the number of fatty acid carbon chains resulted in significant reduction of the inhibition of CPE.View full abstractDownload PDF (93K) -
Taisuke Itaya, Tae Kanai, Takehiko IidaArticle type: Regular Article
Subject area: [not specified]
2002 Volume 50 Issue 4 Pages 530-533
Published: 2002
Released on J-STAGE: July 10, 2002
JOURNAL FREE ACCESSAn improved synthesis of 3-β-D-ribofuranosylwybutine (2) has been achieved by the Wittig reaction between 4,6-dimethyl-9-oxo-3-[2,3,5-tris-O-(tert-butyldimethylsilyl)-β-D-ribofuranosyl]-4,9-dihydro-3H-imidazo[1,2-a]purine-7-carbaldehyde (8) and the phosphorane derived from (R)-2-[(methoxycarbonyl)amino]-3-(triphenylphosphonio)propanoate (9), followed successively by methylation, hydrogenation, and deprotection. On the other hand, the minor nucleoside wybutosine of yeast tRNAPhe was isolated on a scale of 80 μg by partial digestion of unfractionated tRNA (1 g) with nuclease P1, followed successively by reversed-phase column chromatography, complete digestion with nuclease P1/alkaline phosphatase, and reversed-phase HPLC. Comparison of this nucleoside with 2 has unambiguously established that the structure of wybutosine is (αS)-α-[(methoxycarbonyl)amino]-4,6-dimethyl-9-oxo-3-β-D-ribofuranosyl-4,9-dihydro-3H-imidazo[1,2-a]purine-7-butanoic acid methyl ester (2).View full abstractDownload PDF (75K)
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Ampai Phrutivorapongkul, Vimolmas Lipipun, Nijsiri Ruangrungsi, Toshik ...Article type: Note
Subject area: [not specified]
2002 Volume 50 Issue 4 Pages 534-537
Published: 2002
Released on J-STAGE: July 10, 2002
JOURNAL FREE ACCESSStudies on the chemical constituents of the seeds of Pachyrrhizus erosus (Leguminosae) resulted in the isolation of nine known components: five rotenoids [dolineone (3), pachyrrhizone (5), 12a-hydroxydolineone (7), 12a-hydroxypachyrrhizone (9), and 12a-hydroxyrotenone (2)], two isoflavonoids [neotenone (4) and dehydroneotenone (8)], one phenylfuranocoumarin [pachyrrhizine (6)], and a monosaccharide (dulcitol). The full 1H- and 13C-NMR assignments for the isolated products except a sugar, including revision of previous assignments in the literature, are reported. Moderate anti herpes simplex virus (HSV) activity was observed in 12a-hydroxydolineone (7) and 12a-hydroxypachyrrhizone (9) among the isolated products.View full abstractDownload PDF (58K) -
Il Ho Park, Long Zhu Piao, Sung Won Kwon, Yong Jae Lee, Sool Yeon Cho, ...Article type: Note
Subject area: [not specified]
2002 Volume 50 Issue 4 Pages 538-540
Published: 2002
Released on J-STAGE: July 10, 2002
JOURNAL FREE ACCESSSteaming ginseng at high temperature increased its cytotoxicity to SK-Hep-1 hepatoma cancer cells. HPLC separation and fractionation followed by MTT assay revealed that ginsenosides Rg3, Rg5, Rk1, Rs5, and Rs4 are the active principles. Their 50% growth inhibition concentration (GI50) values were 41, 11, 13, 37, and 13 μM, respectively. Cisplatin had a GI50 of 84 μM in the same assay conditions.View full abstractDownload PDF (46K) -
Hironobu Takahashi, Seiko Yoshioka, Shoichi Kawano, Hiroshi Azuma, Yos ...Article type: Note
Subject area: [not specified]
2002 Volume 50 Issue 4 Pages 541-543
Published: 2002
Released on J-STAGE: July 10, 2002
JOURNAL FREE ACCESSA new lignan 1 was isolated together with the five known lignans 2—6 and four sesquiterpenes 7—10 from the seeds of Magnolia praecocissima. The structure of 1 was elucidated by analysis of spectroscopic data and chemical reaction. Furthermore, the absolute configurations of 1, 2, and 3 were determined by the modified Mosher's method.View full abstractDownload PDF (53K) -
Yueh-Hsiung Kuo, Shih-Chang Chien, Shou-Ling HuangArticle type: Note
Subject area: [not specified]
2002 Volume 50 Issue 4 Pages 544-546
Published: 2002
Released on J-STAGE: July 10, 2002
JOURNAL FREE ACCESSFurther studies on the bark of Taiwania cryptomerioides found four new podocarpane derivatives, 1β,13-dihydroxy-8,11,13-podocarpatriene (1), 14,18-dihydroxy-13-methoxy-8,11,13-podocarpatriene (2), 1β,14-dihydroxy-13-methoxy-8,11,13-podocarpatriene-2,7-dione (3), and 3β,14-dihydroxy-13-methoxy-8,11,13-podocarpatrien-7-one (4), together with a known 1β,13,14-trihydroxy-8,11,13-podocarpatrien-7-one (5). Those structures were elucidated principally from spectral evidence.View full abstractDownload PDF (49K) -
Taisuke Itaya, Tae Kanai, Takehiko SawadaArticle type: Note
Subject area: [not specified]
2002 Volume 50 Issue 4 Pages 547-548
Published: 2002
Released on J-STAGE: July 10, 2002
JOURNAL FREE ACCESSLarge-scale isolation of the minor nucleoside wyosine of torula yeast tRNAPhe was accomplished by a combination of enzymatic digestion and reversed-phase chromatography: the wyosine-containing nucleotide fraction, which was obtained by partial digestion of unfractionated tRNA (1 g) with nuclease P1, was concentrated by reversed-phase column chromatography followed by complete digestion with nuclease P1/alkaline phosphatase. The nucleoside mixture thus obtained was purified by reversed-phase HPLC, providing wyosine (70 μg). Comparison of this nucleoside with a chemically synthesized authentic sample has unambiguously established that the structure of wyosine is 4,6-dimethyl-3-β-D-ribofuranosyl-3,4-dihydro-9H-imidazo[1,2-a]purin-9-one (2).View full abstractDownload PDF (45K) -
Munetaka Kunishima, Akiko Kitao, Chiho Kawachi, Yasunobu Watanabe, Shi ...Article type: Note
Subject area: [not specified]
2002 Volume 50 Issue 4 Pages 549-550
Published: 2002
Released on J-STAGE: July 10, 2002
JOURNAL FREE ACCESSRacemization of the C-terminal amino acid (Ala) has been studied in various solvents during coupling between 4-methoxybenzyloxycarbonyl (Z(OMe))-Gly-L-Ala-OH and phenylalanine benzyl ester (H-Phe-OBzl) with 4-(4,6-dimethoxy-1,3,5-thiazin-2-yl)-4-methylmorpholinium chloride (DMT-MM). The reaction occurred without substantial racemization in AcOEt, tetrahydrofuran (THF), N,N-dimethylformamide (DMF), CH3CN, and 2-PrOH, while a slight racemization was observed in dimethyl sulfoxide (DMSO), EtOH, and MeOH. The extent of racemization may correlate with the polarity of the solvents.View full abstractDownload PDF (36K) -
Yasunori Yaoita, Yuko Yoshihara, Rie Kakuda, Koichi Machida, Masao Kik ...Article type: Note
Subject area: [not specified]
2002 Volume 50 Issue 4 Pages 551-553
Published: 2002
Released on J-STAGE: July 10, 2002
JOURNAL FREE ACCESSTwo edible mushrooms, Pleurotus eryngii and Panellus serotinus, have been investigated chemically. Two new sterols, 5α,9α-epidioxy-8α,14α-epoxy-(22E)-ergosta-6,22-dien-3β-ol (1) and 3β,5α-dihydroxyergost-7-en-6-one (2), have been isolated from P. eryngii, together with six known ones (3—8). Compound 1 was also isolated from P. serotinus. The structures of the new compounds were elucidated on the basis of their spectral data.View full abstractDownload PDF (56K) -
Thorsteinn Thorsteinsson, Már Másson, Tomi Jarvinen, Tap ...Article type: Note
Subject area: [not specified]
2002 Volume 50 Issue 4 Pages 554-557
Published: 2002
Released on J-STAGE: July 10, 2002
JOURNAL FREE ACCESSVarious 4,5-dihydroisoxazol-3-yl fatty acid ester derivatives of cycloserine were synthesized to improve skin permeation of cycloserine. The ester derivatives were prepared by using the tert-butoxycarbonyl (t-Boc) protection strategy. The 4,5-dihydroisoxazol-3-yl esters were readily hydrolysed in an aqueous buffer solution, and the degradation profiles showed both specific acid and specific base catalysis. In 50% human serum the formation of cycloserine was observed, but enzymatic catalysis was limited. Delivery through hairless mouse skin was investigated, and the apparent permeability coefficient was measured based on the flux of cycloserine into the receptor phase. The skin permeation of cycloserine across the hairless mouse skin was increased up to 20-fold by the fatty acid esters. The 4,5-dihydroisoxazol-3-yl fatty acid esters of cycloserine can therefore be considered as new topical prodrugs with the potential use in treatment of various skin infections.View full abstractDownload PDF (56K) -
Yoshimitsu Nagao, Satoshi Miyamoto, Kazuhiko Hayashi, Ado Mihira, Shig ...Article type: Note
Subject area: [not specified]
2002 Volume 50 Issue 4 Pages 558-562
Published: 2002
Released on J-STAGE: July 10, 2002
JOURNAL FREE ACCESS(RS)-1 (85% ee) was prepared by utilizing a porcin pancreatic lipase-promoted hydrolysis of sulfinyldiacetic acid dimethyl ester (8) which was derived from thiodiacetic acid (7). (RS)-1 (99% ee) and (SS)-1 (99% ee) were readily obtained by methanolysis of (RS,S)-12 and (SS,S)-12 with MeONa in MeOH. (RS,S)-12 and (SS,S)-12 were furnished by chromatographic separation of the diastereomeric mixture, obtained by oxidation of thiodiacetic mono-carboxylic acid (11) with 30% H2O2 followed by dehydrative condensation of the resultant sulfinyldiacetic mono-carboxylic acid with 4(S)-isopropyl-1,3-thiazolidine-2-thione. (RS)-1 (99% ee) was successively treated with (TMS)2NLi, Ac2O, and TMSOTf to give a major chiral-3 product in 75% ee and in a highly chemoselective manner (chiral-3 : chiral-2=93 : 7).View full abstractDownload PDF (73K)
Communicatins to the Editor
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Ryuichi Ueoka, Yoko Matsumoto, Shigeru Hirose, Koichi Goto, Masahiro G ...Article type: Communication to the Editor
Subject area: [not specified]
2002 Volume 50 Issue 4 Pages 563-565
Published: 2002
Released on J-STAGE: July 10, 2002
JOURNAL FREE ACCESSSugar parts play important roles in recognizing molecules on the cell membranes. We successfully produced sugar-type micellar surfactants, lactonoalkylamide (LacCn), for the first time. Spherical vesicles, three-component hybrid liposomes, were obtained after the sonication of the mixture of L-α-dimyristoylphosphatidylcholine (DMPC), Tween 20 and LacCn (DMPC : Tween 20 : LacCn=65 : 7 : 28). It is noteworthy that high inhibitory effects of the three-component hybrid liposomes composed of DMPC, Tween 20, and LacCn (DMPC : Tween 20 : LacCn=65 : 7 : 28) on the growth of glioma (U251) and lung adenocarcinoma (RERF-LC-OK) cells were attained in vitro without any drug, although no significant inhibitory effects of any individual component (DMPC, Tween 20, LacCn) or the two-component hybrid liposomes of DMPC and Tween 20 on the growth of tumor cells examined were obtained.View full abstractDownload PDF (62K)
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