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Volume 48, Issue 9
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Eugene A. BRATOEFF, H. HERRERA, E. RAMIRES, K. SOLORZANO, E. MURILLO, ...2000 Volume 48 Issue 9 Pages 1249-1255
Published: September 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe pharmacological activities of 12 pregnane derivatives (4-15) were determined on gonadectomized male hamster flank organs and seminal vesicles as antiandrogens and as 5α-reductase inhibitors. The results from this study indicate that subcutaneous injection of testosterone for 3 d increased the diameter of the pigmented spot in the flank organs, whereas finasteride when injected with testosterone decreased the size of the spot significantly when steroids 4-15 were injected together with testosterone, the diameter of the flank organs of gonadectomized male hamsters, decreased significantly (p<0.005) compared to testosterone. Compound 11 was the most active steroid and reduced the diameter of the pigmented spot more than the other synthesized steroids or finasteride. Subcutaneous injections of testosterone to gonadectomized animals restore the seminal vesicle size lost upon castration. Injection of testosterone plus finasteride decreased significantly the weight of these glands (p<0.005). Steroids 5-15 when injected with testosterone decreased the weight of the seminal vesicles compared to testosterone. Finasteride is a good inhibitor of the conversion of testosterone to dihydrotestosterone (DHT) (low formation of DHT) measured as pmole of DHT/g of protein/h. Steroids 6-15 inhibited the conversion of testosterone to DHT as compared to testosterone however finasteride and 10 appeared to be the most effective compounds. Castration increases the protein content of the seminal vesicles (control) expressed as μg/mg of tissues. Testosterone tends to decrease it significantly, as did compounds 4, 5, 7, 9, and 15. We demonstrated that DHT as well as cyproterone acetate and steroids 5, 6, 8, 9, 11, and 14 at increasing non radioactive steroid concentration, inhibited the binding of [3H]DHT to cytosolic androgen receptor (AR), as indicated by its K1 values. However, 4, 7, 10, 12, and 13 did not have any inhibitory effect.View full abstractDownload PDF (1104K) -
Masahiro SAKAGAMI, Kazutoshi HORIE, Kazutaka NAKAMOTO, Takayuki KAWAGU ...2000 Volume 48 Issue 9 Pages 1256-1263
Published: September 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSialyl Lewis X (SLeX) is well known as a ligand of the cell adhesion molecule E-selectin which is specifically expressed at inflammatory lesion sites. We have synthesized several SLeX-polysaccharide conjugates and examined their potential for drug delivery to inflammatory lesions. The AUC (area under the blood concentration-time curve) 0-24 h of SLeX-CMCht (1), SLeX-CMPul (2) and SLeX-DSH (3) at the inflammatory lesion was about 60-, 300-, and 30-fold higher than that of the monovalent SLeX (7), respectively. Moreover, 1 showed 2-fold higher accumulation in the inflammatory lesion than SLN-CMCht (4), and 2 showed 2.5-fold higher accumulation than SLN-CMPul (5).View full abstractDownload PDF (1397K) -
Tatsuhiko YAMADA, Teruko IMAI, Kiyohisa OUCHI, Masaki OTAGIRI, Fumitos ...2000 Volume 48 Issue 9 Pages 1264-1269
Published: September 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSInteractions of KCA-098 with heptakis(2, 6-di-O-methyl)-β-cyclodextrin (DM-β-CyD) in solution and in the solid state were studied by the solubility method, UV and fluorescence spectroscopy, powder X-ray diffractometry, and thermal analysis. The KCA-098/DM-β-CyD system showed an AL type solubility diagram with stability constants of 5870 and 2220 M-1 in aqueous and 10% methanol solutions, respectively. Following the addition of DM-β-CyD, the maximum UV wavelength of KCA-098 was shifted to a longer wavelength and the fiuorescence intensity was decreased. A similar spectral change was observed when KCA-098 was dissolved in less polar solvents, especially in proton-acceptor solvents, such as acetone and dimethylsulfoxide, suggesting that KCA-098-interacts with DM-β-CyD through not only a hydrophobic interaction but also hydrogen bonding. The solid complex of KCA-098 with DM-β-CyD in a molar ratio of 1 : 1 was prepared by the kneading method and the solvent evaporation method, using organic solvents. Powder X-ray diffractometric and differential scanning calorimetric studies indicated that KCA-098 was dispersed as microparticles on the DM-β-CyD complex in the solid state prepared by the solvent evaporation method although it dispersed as crystals in the sample prepared by the kneading method. The dissolution of KCA-098 from the solid complex prepared by the former method was markedly faster than that prepared by the latter method, although it slowed down with the passage of time. The reduced dissolution of KCA-098 was explained by crystallization to the hydrate form in the medium. These data indicate that poorly water-soluble KCA-098 interacts with DM-β-CyD in water and in the solid state and that a fast-dissolving form of KCA-098 can be obtained by evaporating with DM-β-CyD using organic solvents.View full abstractDownload PDF (898K) -
Fumio ITOH, Yoshio YOSHIOKA, Koichi YUKISHIGE, Sei YOSHIDA, Koichiro O ...2000 Volume 48 Issue 9 Pages 1270-1280
Published: September 01, 2000
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 the related compound (1a), was replaced with various Nω-acyl-, sulfonyl-, carbamoyl- and aryl-2, ω-diaminoalkanoic acids, and the inhibitory effects of the resulting products (9, 11, 14, 18, 21, 23, 25, 30, 36) on dihydrofolate reductase (DHFR), the growth of murine fibrosarcoma Meth A cells, and methotrexate-resistant human CCRF-CEM cells, were examined. Compounds (9a-f) acylated with a hemiphthaloyl group were efficiently synthesized by coupling pyrrolo[2, 3-d]pyrimidine carboxylic acids (7a, b) and Nω-phthaloyl 2, ω-diaminoalkanoic acid methyl esters (6a-c) and subsequent hydrolysis. The other Nω-acyl- and sulfonyl-ornithine analogs (21, 23, 25) were synthesized by acylation of free amino intermediates (19a, b) derived from tert-butoxycarbonyl-ornithine analogs (17a, b). A free ornithine analog (18) did not strongly inhibit Meth A cell growth, whereas all Nω-acyl-, sulfonyl-, carbamoyl- and aryl-ornithine analogs (9, 11, 21, 23, 25, 30, 36) exhibited much more potent inhibitory activities against both DHFR and Meth A cell growth. In particular, compounds 9c, 21k and 36a also showed remarkable growth-inhibitory activities against methotrexate-resistant CCRF-CEM cells. These results demonstrate that the potent inhibitory activities of Nω-masked ornithine analogs against the growth of Meth A cells and methotrexate-resistant CCRF-CEM cells, results from effective uptake via reduced folate carrier and their potent DHFR inhibition.View full abstractDownload PDF (1668K) -
Makio SHIBANO, Daisuke TSUKAMOTO, Rie FUJIMOTO, Yasue MASUI, Hisako SU ...2000 Volume 48 Issue 9 Pages 1281-1285
Published: September 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFour new pyrrolidine alkaloids, broussonetines M, O, P, and Q, were isolated from the branches of Broussonetia kazinoki SIEB. (Moraceae). Broussonetines M, O, P, and Q were formulated as (2R, 3R, 4R, 5R)-2-hydroxymethyl-3, 4-dihydroxy-5-[(10S)-10, 13-dihydroxy-tridecyl]pyrrolidine (1), (2R, 3R, 4R, 5R)-2-hydroxymethyl-3, 4-dihydroxy-5-[(E)9-oxo-13-hydroxy-3-tridecenyl]pyrrolidine (2), (2R, 3R, 4R, 5R)-2-hydroxymethyl-3, 4-dihydroxy-5-[(E)10-oxo-13-hydroxy-3-tridecenyl]pyrrolidine (3), and (2R, 3R, 4R, 5R)-2-hydroxymethyl-3-hydroxy-4-(β-D-glucopyranosyloxy)-5-[10-oxo-13-(β-D-glucopyranosyloxy)tridecyl]pyrrolidine (4) respectively, by spectroscopic and chemical methods. 1-4 inhibited β-glucosidase, β-galactosidase and β-mannosidase.View full abstractDownload PDF (654K) -
Tsutomu HATANO, Yasushi SHINTANI, Yasuhiro AGA, Sumiko SHIOTA, Tomofus ...2000 Volume 48 Issue 9 Pages 1286-1292
Published: September 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo new phenolic compounds, glicophenone (1) and glicoisoflavanone (2), were isolated from commercial licorice, and their structures were elucidated on the basis of spectroscopic data. Antibacterial assays of licorice phenolics for Staphylococcus aureus, including four strains of methicillin-resistant S. aureus (MRSA), and also for Escherichia coli K12 and Pseudomonas aeruginosa PAO1, were then examined. Two compounds among them, 8-(γ, γ-dimethylallyl)-wighteone (21) and 3'-(γ, γ-dimethylallyl)-kievitone (28), showed remarkable antibacterial effects [minimum inhibitory concentrations (MICs), 8 μg/ml] on the MRSA strains and methicillin-sensitive S. aureus. Licochalcone A (14), gancaonin G (20), isoangustone A (24), glyasperins C (30) and D (31), glabridin, (32), licoricidin (33), glycycoumarin (34) and licocoumarone (40) showed antibacterial effects on the MRSA strains with MIC values of 16 μg/ml. Effects on the β-lactam resistance of the MRSA strains were also examined, and licoricidin (33) noticeably decreased the resistance of the MRSA strains against oxacillin, as shown by the reduction in the MICs of oxacillin (lower than 1/128-1/1000 in the presence of 8 μg/ml of 33, and 1/8-1/32 in the presence of 4 μg/ml of 33). Mechanistic study suggested that 33 does not inhibit the formation of penicillin-binding protein 2' (PBP2'), but affects the enzymatic function of PBP2'.View full abstractDownload PDF (1092K) -
Yoshihiro KURODA, Kazuhide MIYAMOTO, Kazufumi TANAKA, Yoshitaka MAEDA, ...2000 Volume 48 Issue 9 Pages 1293-1298
Published: September 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSInteractions between local anesthetics and a sodium channel inactivation gate peptide (Ac-GGQDIFMTEEQK-NH2, MP-1A), which was dissected from the cytoplasmic linker between domains III and IV of the sodium channel α-subunit (G1484-K1495 in rat brain type IIA), have been studied by 1H-NMR spectroscopy. Changes in 1H-NMR chemical shifts of the aromatic proton resonances of dibucaine (pH 7.0) and lidocaine (pH 6.0 and 9.0) in phosphatidylserine (PS) suspensions were observed. The effects of substitution of glutamine (F1489Q; MP-2A) or D-phenylalanine (MP-1A') for L-phenylalanine (F1489) in MP-1A and the effects of substitution of neutral amino acid residues for the corresponding acidic amino acid residues (D1487N, MP-1NA; E1492Q, MP-1QEA; E1493Q, MP-1EQA) in MP-1A, on the aromatic 1H-NMR cheimcal shift changes of dibucaine and lidocaine were also investigated. From these results it was concluded that : the aromatic ring of phenylalanine of MP-1A and the aromatic ring of the cationic form of dibucaine or lidcaine are interacting by π-π stacking; the tertiary amine nitrogen of dibucaine is interacting electrostatically with D1487, whereas that of lidocaine is interacting with E1492.View full abstractDownload PDF (791K) -
Koji URAKAMI, Chiaki KOBAYASHI, Yoshihiko MIYAZAKI, Koji NISHIJIMA, Yo ...2000 Volume 48 Issue 9 Pages 1299-1303
Published: September 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSBenzyl alcohol used as the sample preparation solvent in the determination of residual solvents in pharmaceutical bulks yielded benzene, toluene, and benzaldehyde on capillary gas chromatography (GC) by sonication. The factors responsible for compounds generated are discussed. The quality of benzyl alcohol and the type of sonicator were not involved in the generation of benzene, toluene, and benzaldehyde, whereas matrix contributions were observed. The degradation profiles of benzyl alcohol and its analogous compounds obtained by pyrolysis-GC/mass spectrometric analysis were similar to those obtained by sonication, suggesting that benzyl alcohol is degraded by the high local heat generated by sonication. Consequently, no matter how long it may take to dissolve bulk substances in benzyl alcohol completely, we do not recommend the use of a sonicator in sample preparation for the determination of residual solvents in pharmaceutical bulks.View full abstractDownload PDF (716K) -
Michio IWAI, Hideyuki YOKOYAMA, Hisashi YAMADA, Mineo NIWA, Masakazu K ...2000 Volume 48 Issue 9 Pages 1304-1309
Published: September 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSInsulin-like growth factor I (IGF-I or somatomedin C) is a serum polypeptide with three intramolecular disulfide bond. In the course of synthesis by the recombinant DNA method, three disulfide bond isomers, all of which have Cys18-Cys61 with three combinations of two disulfide bonds formed by Cys6, Cys47, Cys48 and Cys52, were identified. Natural type, isomer II, was proved to have a Cys6-Cys48, Cys18-Cys61, Cys47-Cys52 disulfide bond system. Now, the fourth isomer, isomer V which doesn't have Cys18-Cys61 disulfide, has been isolated, and its novel disulfide bond linkage system was identified by a chemical synthetic method. The supposed conformation constrained in 3D structure for isomer V would be discussed for its biological activity.View full abstractDownload PDF (870K) -
Tsutomu MIMOTO, Naoko HATTORI, Haruo TAKAKU, Sumitsugu KISANUKI, Tomin ...2000 Volume 48 Issue 9 Pages 1310-1326
Published: September 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWe designed and synthesized a new class of peptidomimetic human immunodeficiency virus protease inhibitors containing a unique unnatural amino acid, allophenylnorstatine [Apns; (2S, 3S)-3-amino-2-hydroxy-4-phenylbutyric acid], with a hydroxymethylcarbonyl isostere as the active moiety. From a structure-activity relationship study of HIV-1 protease inhibition, enzyme selectivity for other aspartyl proteases, the antiviral activity and pharmacokinetics in rats, 24c (KNI-227) and 24d (KNI-272, our first clinical candidate) were found to be selective and orally potent HIV protease inhibitors. Moreover, an improvement of the pharmacokinetic features of KNI-272 provided two long-lasting and highly bioavailable compounds (24g : JE-2178, 24h : JE-2179).View full abstractDownload PDF (2531K) -
Masayuki YOSHIKAWA, Toshio OHTA, Atsuhiro KAWAGUCHI, Hisashi MATSUDA2000 Volume 48 Issue 9 Pages 1327-1331
Published: September 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe methanolic extract and the ethyl acetate-soluble and methanol-eluted fractions from Chinese Moutan Cortex, the roots of Paeonia suffruticosa ANDREWS, were found to exhibit scavenging effect on 1, 1-diphenyl-2-picrylhydrazyl radical and superoxide anion radical generated by the xanthine-xanthine oxidase system. Two monoterpenes called paeonisuffrone and paeonisuffral were isolated from the ethyl acetate-soluble fraction. Their absolute stereostructures were elucidated on the basis of chemical and physiochemical evidence, which included the application of a modified Mosher's method and lipase catalyzed debenzoylation reaction.View full abstractDownload PDF (779K) -
Yili WANG, David L. SOPER, Michelle J. DIRR, Mitchell A. DELONG, Biswa ...2000 Volume 48 Issue 9 Pages 1332-1337
Published: September 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA novel class of saturated prostaglandin F2α sulfonamide analogs have been synthesized and evaluated in the human FP receptor binding assay for potential use in the treatment of osteoporosis. These compounds have been nodified at the C1 carboxylic acid moiety and at the C16-C20 region of the prostaglandin. Based on the structure-activity relationships, it was found that at C1, the aryl sulfonamide analogs possessed greater affinity for the hFP receptor when compared to alkyl sulfonamides. When the sulfonamide was introduced into the C16-C<20> region (omega chain) of the prostaglandin, a significant reduction in binding was observed. These results are discussed within the framework of a proposed model for the human FP receptor.View full abstractDownload PDF (970K) -
Masami KAWASE, Setsuo SAITO, Teruo KURIHARA2000 Volume 48 Issue 9 Pages 1338-1343
Published: September 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSα-Trifluoromethylated acyloins (2 and 6) have been prepared from α-hydroxy acids (1), N-acylprolines (5) or N-acyl-N-alkyl α-amino acids (8) by novel transformation reactions with trifluoroacetic anhydride (TFAA) in the presence of pyridine. The former reaction of 1 could proceed through mesoionic 1, 3-dioxolium-4-olates, whereas the latter two reactions of α-amino acids (5 and 8) could involve mesoionic 1, 3-oxazolium-5-olates. The reaction of 1 with TFAA shows more potential for practical applications because of the ready availability of the starting materials and ease of manipulation.View full abstractDownload PDF (828K) -
Ya-Ching SHEN, Ching-Yeu CHEN, Meng-Chieh HUNG2000 Volume 48 Issue 9 Pages 1344-1346
Published: September 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new 2(3→20) abeotaxane, taxumairone A (1), and a new cis-p-coumaroyl myo-inositol have been isolated from the seeds of Taxus mairei in addition to taxin B (2), taxinine A, taxuspine X, decinnamoyltaxinine E, 5α-cinnamoyloxy-9α, 10β, 13α-triacetoxy-taxa-4(20)11-diene and 5α-cinnamoyloxy-2α, 9α, 10β, 13α-tetraacetoxy-taxa-4(20)11-diene. The structure of 1 was determined by 2D-NMR spectral analysis and chemical correlation with taxin B (2). Compound 1 exhibited potent cytotoxicity against human colon carcinoma cells with an ED50 of 0.1 μg/ml.View full abstractDownload PDF (553K) -
Uthai SOTANAPHUN, Rutt SUTTISRI, Vimolmas LIPIPUN, Rapepol BAVOVADA2000 Volume 48 Issue 9 Pages 1347-1349
Published: September 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new ursane-type triterpene, glyptopetolide, was isolated along with two known triterpenoids, isoarborinol and cangoronine, from the stem bark of Glyptopetalum sclerocarpum LAWS. (Celastraceae). The structure of glyptopetolide was elucidated as 3, 4-seco-14α, 27-cyclo-urs-4(23)-en-3, 11α-olide by spectroscopic analysis.View full abstractDownload PDF (455K) -
Wen-Bin PAN, Fang-Rong CHANG, Yang-Chang WU2000 Volume 48 Issue 9 Pages 1350-1353
Published: September 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSChemical examination of the underground parts of Tupistra chinensis led to the isolation of two new 5β-spirostane type steroidal sapogenins, tupichigenin B (1) and C (2), together with two known steroidal sapogenins, ranmogenin A (3) and Δ25(27)-pentrogenin (4). The structures of 1 and 2 were established as spirost-25(27)-ene-1β, 3β, 4β, 5β, 6β-pentaol and 1β, 2β, 3β, 4β, 5β-pentahydroxyspirost-25(27)-en-6-one, respectively, on the basis of detailed analysis of their physical and spectral data.View full abstractDownload PDF (612K) -
Jian-Chen LI, Toshihiro NOHARA2000 Volume 48 Issue 9 Pages 1354-1355
Published: September 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThree novel benzophenione C-glucosides, 3'-C-β-D-glucopyranosyl-2', 4', 6', 3-tetrahydroxy-4-methoxybenzophenone, 3'-C-β-D-glucopyranosyl-2', 4', 6'-trihydroxy-3, 4-dimethoxybenzophenone and 4'-C-β-D-glucopyranosyl-2', 3', 5', 6', 3-pentahydroxybenzophenone, named telephenones A, B, and C were isolated from the whole plant of Polygala telephioides WILLD and their structures determined by analysis of spectroscopic data.View full abstractDownload PDF (411K) -
Yasunori YAOITA, Takaaki ISHIZUKA, Rie KAKUDA, Koichi MACHIDA, Masao K ...2000 Volume 48 Issue 9 Pages 1356-1358
Published: September 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFour new phytosphingosine-type ceramides, (2S, 3S, 4R)-2-[(2'R)-2'-hydroxydocosanoylamino]-1, 3, 4-octadecanetriol (1), (2S, 3S, 4R)-2-[(2'R)-2'-hydroxytricosanoylamino]-1, 3, 4-octadecanetriol (2), (2S, 3S, 4R)-2-[(2'R)-2'-hydroxypentacosanoylamino]-1, 3, 4-octadecanetriol (3) and (2S, 3S, 4R)-2-[(2'R)-2'-hydroxyhexacosanoylamino]-1, 3, 4-octadecanetriol (4), have been isolated from the fruit bodies of Grifola frondosa. The structures of the new compounds were elucidated on the basis of their spectral data.View full abstractDownload PDF (517K) -
Mitsuteru NUMAZAWA, Akiko YOSHIMURA2000 Volume 48 Issue 9 Pages 1359-1362
Published: September 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS4β, 5β-Epoxy derivatives of 16α-hydroxyandrostenedione (2), one of the natural substrates for aromatase, and its 19-oxygenated compounds 4 and 5 were synthesized as mechanistic and catalytic probes for the enzyme reaction. Treatment of 16α-bromoandrostenedione (13) or its 19-hydroxy analog 19 which was prepared from 3β-hydroxy-19-(tert-butyldimethylsiloxy)androst-5-en-17-one (16) in three steps, with H2O2 and NaOH followed by controlled alkaline hydrolysis with NaOH in aqueous pyridine stereospecifically yielded 4β, 5β-epoxy-16α-ol 15 or 4β, 5β-epoxy-16α, 19-diol 22, respectively. Oxidation of 16β-bromo-4β, 5β-epoxy-19-ol 21 with pyridinium dichromate followed by controlled alkaline hydrolysis produced 4β, 5β-epoxy-16α-hydroxy-19-al 24.View full abstractDownload PDF (671K) -
Tokujiro KITAGAWA, Chinatsu TSUTSUI2000 Volume 48 Issue 9 Pages 1363-1366
Published: September 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe reaction of the N-furfuryloxamic acid sodium salt (12) with 1, 1'-oxalyldiimidazole (ODI) yielded the imidazolide (13) as an intermediate, and this directly reacted with 2-aminothiazole derivatives (14) or 2-aminobenzothiazole derivatives (15) under essentially neutral conditions to afford the N'-[2-(substituted thiazolyl)]- or N'-[2(substituted benzothiazolyl)]-N-furfuryloxamides (6 or 7).The prepared compounds (6 and 7) were examined for plant growth regulatory activity in a seed germination assay. The examination resulted in the discovery of some new revelations that N'-[2-(5, 6-dimethylbenzothiazlyl)]-N-furfuryloxamide (7c) at the concentration of 1.0×10-3M completely inhibited the radicle growth of both rape and leek seedings.View full abstractDownload PDF (621K) -
Hong-Xi XU, Dong-Sheng MING, Hui DONG, Paul Pui-Hay BUT2000 Volume 48 Issue 9 Pages 1367-1369
Published: September 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSGeumonoid (1), a new triterpene, was isolated from Geum japonicum. Its structure was elucidated on the basis of 1D, 2D NMR and MS spectroscopic analysis. Compound 1 showed inhibitory activity against HIV-1 protease.View full abstractDownload PDF (486K) -
Naotsuka HIKAGE, Hironori FURUKAWA, Ken-ichi TAKAO, Susumu KOBAYASHI2000 Volume 48 Issue 9 Pages 1370-1372
Published: September 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSBiogenetic-like one-step construction of the pentacyclic aminal core of zoanthamine/norzoanthamine alkaloids was accomplished in high yield from the suitably protected monocyclic aminohydroxy diketocarboxylic acid 7 by heating in aqueous acetic acid.View full abstractDownload PDF (484K) -
K. S. KRISHNAVENI, J. V. SRINIVASA RAO2000 Volume 48 Issue 9 Pages 1373-1374
Published: September 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSPhytochemical investigation on the constituents of heartwood of Pterocarpus santalinus resulted in the isolation of a new acylated isoflavone glucoside. The structure of the new compound was elucidated on the basis of spectral studies as 4', 5-dihydroxy-7-O-methyl isoflavone 3'-O-β-D-(3"-E-cinnamoyl)glucoside.View full abstractDownload PDF (400K) -
Takeshi KINOSHITA2000 Volume 48 Issue 9 Pages 1375-1377
Published: September 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSNew cassane diterpenes named neocaesalpins C and D were isolated from the Philippine crude drug calumbibit botanically originating from the seeds of Caesalpinia bonduc (Fabaceae), and their structures were elucidated on the basis of the spectroscopic evidence. These compounds are characterized by the presence of the α, β-butenolide moiety. Although a number of cassane furanoditerpenes have been known to occur in the same plant species, such constituents could not be isolated from the crude drug of Philippine orgin in this study. It is presumed that the chemical difference resulted from chemical differentiation of the species.View full abstractDownload PDF (480K) -
Takashi MICHIDA, Eriko OSAWA, Yumiko YAMAOKA2000 Volume 48 Issue 9 Pages 1378-1379
Published: September 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA semi-empirical calculation (PM3) was applied to elucidate the anodic oxidation mechanisum of N, N-dimethylaniline (DMA) and the dimerization of a cation radical (A) derived from DMA was ruled out. The heat of reaction value of the dimerization of A was 42.43 kcal/mol. We propose the following. Cation radical A reacts with DMA to generate another cation radical (D). This reaction was exothermic and the heat of reaction value and the activation energy were -0.35 kcal/mol and 1.31 kcal/mol, respectively. Deprotonation of D by DMA gives neutral radical (E), which is oxidized to TMB by A. All these reactions were exothermic.View full abstractDownload PDF (382K) -
Hidetoshi FUJIWARA, Kouki KITAGAWA2000 Volume 48 Issue 9 Pages 1380-1383
Published: September 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new heterocyclic compound, [1]benzopyrano[2, 3, 4-kl]acridin-3-ol was synthesized by cyclization of xanthone derivatives. The key compound, 1-(3'-methoxyanilino)-xanthone, was prepared from 1-aminoxanthone. [1]benzopyrano[2, 3, 4-kl]acridin-3-ol analogues, [1]benzothiopyrano[2, 3, 4-kl]acridin-3-ol, pyrido[3', 2' : 5, 6]pyrano[2, 3, 4-kl]acridin-3-ol and pyrido[3', 2' : 5, 6]thiopyrano[2, 3, 4-kl]acridin-3-ol were synthesized by the same method.View full abstractDownload PDF (528K) -
Mariko ASO, Kazutoshi RYUO, Mitsumasa KONDO, Hiroshi SUEMUNE2000 Volume 48 Issue 9 Pages 1384-1386
Published: September 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA novel method of preparing C-4' oxidezed nucleotide, a monomeric model of an alkali labile lesion (1) has been studied. The C-4' selenated 4a and 4b were found to be effective in preparing 3, a monomeric model of 1, by the reaction with NBS (N-bromosuccinimide). The successive reaction of 3 with amine at room temperature afforded the α, β-unsaturated γ-methylene-γ-lactam (2) in good yield.View full abstractDownload PDF (495K) -
Yoshiki KASHIWADA, Junko CHIYO, Yasumasa IKESHIRO, Tsuneatsu NAGAO, Hi ...2000 Volume 48 Issue 9 Pages 1387-1390
Published: September 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS3-Alkylamido-3-deoxy-betulinic acids were synthesized and evaluated for anti-HIV activity as part of the structure-activity relationship study of the potent anti-HIV agent 3-O-(3', 3'-dimethyl)-succinyl-betulinic acid (DSB) (2). 3α-Diglycorylamide-3-deoxy-betulinic acid demonstrated relatively potent anti-HIV activity (EC500.24 μM, TI 728). However, replacing the ester group at C-3 in 2 and its analogues with an amido group yielded inactive or much less potent compounds against HIV replication, indicating that the ester group at C-3 in 2-4 is essential for potent anti-HIV activity.View full abstractDownload PDF (742K) -
Akimori WADA, Yuki NOMOTO, Kenji TANO, Eriko YAMASHITA, Masayoshi ITO2000 Volume 48 Issue 9 Pages 1391-1394
Published: September 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSPalladium catalyzed cross coupling reactions of a vinyl triflate intermediate and various alkenyl stananes afforded trisubstituted Z-olefins stereoselectively in high yields. These olefins were then converted to the corresponding 9Z-retinoic acids via Horner-Emmons reaction and subsequent basic hydrolysis in excellent yields.View full abstractDownload PDF (683K) -
Mitsuhiro YOSHIMATSU, Masaru HIBINO2000 Volume 48 Issue 9 Pages 1395-1398
Published: September 01, 2000
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSα-Trifluoromethyl allenol ethers 9a-e were prepared in moderate to good yields by the Julia-Lythgoe process using β-ethoxy-β-trifluoromethyl vinylic sulfone 3. Several reactions of 9c were examined to give α, β-unsaturated trifluoromethyl ketone derivatives 11 and 12.View full abstractDownload PDF (774K)
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