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Volume 52, Issue 6
Displaying 1-28 of 28 articles from this issue
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Regular Articles
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G. C. Onunkwo, H. C. Egeonu, M. U. Adikwu, J. E. Ojile, A. K. Olowosul ...2004 Volume 52 Issue 6 Pages 649-653
Published: 2004
Released on J-STAGE: June 01, 2004
JOURNAL FREE ACCESSThe formulation of Garcinia kola seeds into tablet dosage form and evaluation of some physical properties of the tablets are presented. A chemical assay was conducted on the dry, powdered seeds as well as the crude aqueous extract of the seeds. The dry powdered seeds contain 0.003% of flavonoids while the crude extract contained 0.007% of flavonoids based on rutin used as the standard. The powdered material (50 mg) and crude extract (10 mg) were formulated into tablets using the wet granulation method. Named binders were evaluated in these formulations. The various tablet parameters were evaluated, namely: weight variation, thickness and diameter, hardness, friability, disintegration time, dissolution profile and content uniformity. The results indicated that the tablets had good disintegration time, dissolution and hardness/friability profiles. Tablets formulated with starch had the best disintegration properties but were consequently very friable. Tablets formulated from 10 mg of the crude extract needed a larger proportion of diluents, which affected the tablet properties.View full abstractDownload PDF (109K) -
Four New Steroid Constituents from the Waste Residue of Fibre Separation from Agave americana LeavesJian-Ming Jin, Ying-Jun Zhang, Chong-Ren Yang2004 Volume 52 Issue 6 Pages 654-658
Published: 2004
Released on J-STAGE: June 01, 2004
JOURNAL FREE ACCESSThree new steroidal saponins, named agamenosides H—J (1—3), and a new cholestane steroid agavegenin D (4) were isolated from the waste residue of fibre separation from Agave americana leaves, together with six known steroids. Structures of the new compounds 1—4 were deduced to be (22S,23S,24R,25S)-24-[(β-D-glucopyranosyl)oxy]-5α-spirostane-3β,6α,23-triol 6-O-β-D-glucopyranoside (1), (22S,23S,24R,25S)-5α-spirostane-3β,23,24-triol 24-O-β-D-glucopyranoside (2), (22S,23S,25R,26S)-23,26-epoxy-5α-furostane-3β,22,26-triol 26-O-β-D-glucopyranoside (3), and (22S,25S)-5α-cholestane-3β,16β,22,26-tetrol (4), respectively, by means of spectroscopic analysis, including extensive 1D and 2D NMR data, and the results of hydrolytic cleavage.View full abstractDownload PDF (92K) -
Pierre-Jean Aragon, Ange-Désiré Yapi, Frédé ...2004 Volume 52 Issue 6 Pages 659-663
Published: 2004
Released on J-STAGE: June 01, 2004
JOURNAL FREE ACCESSIndoloquinoline alkaloid cryptolepine and pyridocarbazole alkaloid ellipticine are of great interest because in vitro and in vivo studies revealed their good cytotoxic properties. In order to obtain some biologically active analogs of these compounds, we developped a synthesis based on the photocyclisation of tertiary N-methylated enaminones derived from cyclopentane-1,3-dione and 3 or 6-aminoquinoline. The angular cyclised compounds thus obtained were submitted to Beckmann rearrangement, preceded by the formation of a Z oxime. Finally, the δ-lactame ring was oxidized using 10% palladium/carbon in diphenylether and pyridopyrroloquinolines were obtained. These compounds and the intermediate lactams and cyclopentanopyrroloquinolines were tested in vitro on K 562 cells and A 2780 doxorubicine sensitive and resistant cells. All compounds were less effective than doxorubicine in sensitive cells but their activity wasn't decreased by MDR resistance.View full abstractDownload PDF (125K) -
Hiromasa Horikiri, Noriyuki Hirano, Yoichiro Tanaka, Junji Oishi, Hito ...2004 Volume 52 Issue 6 Pages 664-669
Published: 2004
Released on J-STAGE: June 01, 2004
JOURNAL FREE ACCESSSyntheses of 10-oxo, 10α-hydroxy, and 10β-hydroxy derivatives of a potent κ-opioid receptor selective agonist, TRK-820, are described. These derivatives were supposed to be potential degradation products in formulation of TRK-820 as a result of autoxidation. 10-Oxo-TRK-820 11 was derived from 10-oxo-4,5-epoxymorphinan 14 in 10 steps in 32% overall yield. Reduction of the 10-oxo group in 4,5-epoxymorphinan with NaBH4 gave 10β-hydroxy-4,5-epoxymorphinan, exclusively. A stepwise inversion method of the 10β-hydroxy group to produce 10α-hydroxy-4,5-epoxymorphinan was established. By HPLC analyses, 10α-hydroxy-TRK-820 12 was confirmed to be one of the degradation products in developing formulation of TRK-820.View full abstractDownload PDF (141K) -
Kuniaki Kawamura, Hiromasa Horikiri, Jun Hayakawa, Chie Seki, Ken-ichi ...2004 Volume 52 Issue 6 Pages 670-674
Published: 2004
Released on J-STAGE: June 01, 2004
JOURNAL FREE ACCESSChemical syntheses of three kinds of potential metabolites of TRK-820, a potent κ-opioid receptor agonist, were described. One of the potential metabolites 2, 17-N-dealkylated TRK-820, was synthesized starting from noroxycodone through 8 steps in 21% total yield. Glucuronidation of intermediate 10 and compound 1, the free base of TRK-820, was carried out stereoselectively to give 3-O-β-D-glucuronides 15 and 16 in good yields, respectively. Syntheses of potential conjugated metabolites 3 and 4 were accomplished through 10 steps and 2 steps in 11% and 43% total yields, respectively. Among the potential metabolites of TRK-820, compounds 2 and 4 were identified as metabolites in human hepatocytes. The results of pharmacological studies of compounds 2, 3, and 4 are described.View full abstractDownload PDF (123K) -
Toshihiko Kaneko, Richard S. J. Clark, Norihito Ohi, Fumihiro Ozaki, T ...2004 Volume 52 Issue 6 Pages 675-687
Published: 2004
Released on J-STAGE: June 01, 2004
JOURNAL FREE ACCESSNovel piperidine carboxylic acid derivatives of 10H-pyrazino[2,3-b][1,4]benzothiazine were prepared and evaluated for their inhibitory activity on the upregulation of adhesion molecules such as intercellular adhesion molecule-1 (ICAM-1). Replacement of the methanesulfonyl group on the piperidine ring of previously prepared derivatives with a carboxylic acid-containing moiety resulted in a number of potent adhesion molecule inhibitors. Of these, (anti) [3-(10H-pyrazino[2,3-b][1,4]benzothiazin-8-yl)methyl-3-azabicyclo[3.3.1]non-9-yl]acetic acid 2q (ER-49890), showed the most potent oral inhibitory activities against neutrophil migration in an interleukin-1 (IL-1) induced paw inflammation model using mice, and leukocyte accumulation in a carrageenan pleurisy model in the rat, and therapeutic effect on collagen-induced arthritis in rats.View full abstractDownload PDF (286K) -
Jiang-Jing Gao, Norio Nakamura, Byung-Sun Min, Akiko Hirakawa, Feng Zu ...2004 Volume 52 Issue 6 Pages 688-695
Published: 2004
Released on J-STAGE: June 01, 2004
JOURNAL FREE ACCESSFor quantitative determination of 19 triterpene constituents, including six ganoderma alcohols (1—6) and 13 ganoderma acids (7—19), in the products of Ganoderma lucidum, an analytical system was developed using high-performance liquid chromatography with an ODS column. The mobile phase was a linear gradient of 1% AcOH/H2O–CH3CN and 2% AcOH/H2O–CH3CN, and the elution profile was monitored at 243 and 250 nm for ganoderma alcohols and acids, respectively. The relative standard deviations of this method were less than 2.35% and 2.18% (n=5) for intraday and interday assays, and the recoveries were 90.9—100.8% and 93.4—103.9% for constituents of alcohol and acid groups, respectively. This system was applied to a quantitative determination of the constituents in 10 different products of G. lucidum: six usual umbrella forms of the fruiting bodies, three antlered forms of the fruiting bodies and spores, and eight specimens from the same G. lucidum strain, which was parasitized on logs from different plants or different fungus beds. The analytical results indicated that the quantity and composition of these triterpenes differed appreciably among various specimens, but the relative ratio of the alcohols and acids was not significantly different when the same strain of G. lucidum was used.View full abstractDownload PDF (237K) -
Lara Milián, Rossana Estellés, Belén Abarca, Rafa ...2004 Volume 52 Issue 6 Pages 696-699
Published: 2004
Released on J-STAGE: June 01, 2004
JOURNAL FREE ACCESSFour phenanthrene and one aporphine alkaloids semi-synthesized from boldine were evaluated for their inhibitory effect on reactive oxygen species (ROS) generation. ROS generation by neutrophils stimulated with N-formyl-methionyl-leucyl-phenylalanine was inhibited in a concentration dependent manner. Alkaloids exerted similar inhibitory effect in the hypoxanthine–xanthine oxidase system than in stimulated neutrophils, which could be attributed to a direct ROS scavenging activity. None of the alkaloids assayed had any effect on xanthine oxidase activity. Therefore the synthesized alkaloids might constitute an alternative therapy in inflammation disorders in which ROS generation is involved.View full abstractDownload PDF (93K) -
Hitomi Koutaka, Jun-ichi Kosuge, Noboru Fukasaku, Tomoya Hirano, Kazuy ...2004 Volume 52 Issue 6 Pages 700-703
Published: 2004
Released on J-STAGE: June 01, 2004
JOURNAL FREE ACCESSZnAB has the combined structure of N,N-bis(2-pyridylmethyl)ethylenediamine as a specific chelater for Zn2+ and 1,3,5,7-tetramethyl-8-phenyl-boron dipyrromethene as a fluorophore. Complexation of ZnAB with Zn2+ produces a remarkable enhancement of fluorescence intensity. ZnAB has the advantages of less sensitivity to solvent polarity and pH than fluorescein-based Zn2+ probes. Furthermore, it is not influenced by other cations, such as Na+, K+, Ca2+, and Mg2+, which exist at high concentrations under physiological conditions, even at 2.5 mM. The results show that ZnAB is a Zn2+ probe suitable for biological applications.View full abstractDownload PDF (121K) -
Ryuichi Narazaki, Tsutomu Harada, Norishige Takami, Yoshiteru Kato, Ta ...2004 Volume 52 Issue 6 Pages 704-707
Published: 2004
Released on J-STAGE: June 01, 2004
JOURNAL FREE ACCESSThe aim of this study was to develop a simple and suitable disintegration method specific for rapid disintegrating tablets (RDTs). The new disintegration method that we propose employs a rotary shaft to exert mechanical pressure on the RDT. To assess our method, we manufactured several placebo RDTs and exposed them to severe storage conditions (60°C/75%RH for 1week) in order to obtain RDTs with a wide range of disintegration times. These placebo RDTs were utilized to compare the disintegration times obtained by several methods, including the proposed method. As expected, the disintegration time of the placebo RDTs in human sensory test varied widely. The disintegration times determined by the conventional disintegration test were in good correlation to those in human sensory test, but the slope was far from 1 (0.241). There was no correlation between the disintegration time of RDTs in human sensory test and those determined by the conventional dissolution test. In contrast, we acquired good correlation between the disintegration times obtained with the new method and those in human sensory test, and the slope was very close to 1 (0.858). We attribute this to the use of mechanical stress in the new method, similar to that the RDT is subject to in the oral cavity. We therefore concluded that the proposed method was suitable for the measurement of the disintegration time of RDTs. This new method might provide a valuable approach for the establishment of the official disintegration test for RDTs in the future.View full abstractDownload PDF (220K) -
Noriaki Funasaki, Seiji Ishikawa, Shun Hirota, Saburo Neya, Tomoyuki N ...2004 Volume 52 Issue 6 Pages 708-713
Published: 2004
Released on J-STAGE: June 01, 2004
JOURNAL FREE ACCESSThe structure and ethanol complexation of a cyclic tetrasaccharide (CTS) in aqueous solution were investigated by proton NMR spectroscopy and molecular mechanics calculations. Two glucose units, A and B, of CTS are alternatively bonded by α-1,3 and α-1,6 linkages. The overlapped signals of protons A5, A6S, A6R, B3, B6S and B6R were resolved by spectral simulations to determine their chemical shifts and vicinal coupling constants. All vicinal coupling constants except for the A5–A6 spin system are consistent with the dihedral angles in the X-ray crystal structure. Each of protons A5, A6S, and A6R in the two units of A is equivalent with respect to the chemical shift. The vicinal coupling constants of 3J5–6S and 3J5–6R for unit A are close to the average of two rotamers that are present in crystals. The intensities of cross-peaks in the rotating frame nuclear Overhauser effect spectroscopy (ROESY) spectrum were rather well correlated with the effective distances calculated for the X-ray structure and molecular mechanics structures calculated in vacuo and water, although they are slightly better correlated with molecular mechanics structure in vacuo than with the other structures. From the changes of the chemical shifts of several CTS protons with increasing ethanol concentration, it was suggested that adsorption sites of ethanol on the plate structure of CTS are protons B2 and B4 (site B) in the concave face side and protons A1 and A2 (site A) in the convex back side. The binding constants for sites A and B are 0.0061 and 0.0176 M−1, respectively. These binding constants are much smaller than a value of 4.1 M−1 for the ethanol–α-cyclodextrin complex.View full abstractDownload PDF (561K) -
Ju Sun Kim, Sang Hee Shim, Yong Nan Xu, Sam Sik Kang, Kun Ho Son, Hyeu ...2004 Volume 52 Issue 6 Pages 714-717
Published: 2004
Released on J-STAGE: June 01, 2004
JOURNAL FREE ACCESSFive new phenolic glycosides, 2-β-D-glucopyranosyloxy-5-hydroxyphenylacetic acid methyl ester (4), 4-hydroxy-2-[3-hydroxy-3-methylbutyl]-5-methylphenyl β-D-glucopyranoside (5), 4-hydroxy-2-[(E)-4-hydroxy-3-methyl-2-butenyl]-5-methylphenyl β-D-glucopyranoside (7), 4-hydroxy-2-[(2E,6Z)-8-β-D-glucopyranosyloxy-3,7-dimethylocta-2,6-dien-1-yl]-5-methylphenyl β-D-glucopyranoside (8), and 2,7-dimethyl-1,4-dihydronaphthalene-5,8-diol 5-O-β-D-xylopyranosyl(1→6)-β-D-glucopyranoside (10), were isolated from the whole plants of Pyrola japonica (Pyrolaceae), together with androsin, (−)-syringaresinol glucoside, homoarbutin, pirolatin, hyperin, monotropein and chimaphilin.View full abstractDownload PDF (96K) -
Arno Hazekamp, Young Hae Choi, Robert Verpoorte2004 Volume 52 Issue 6 Pages 718-721
Published: 2004
Released on J-STAGE: June 01, 2004
JOURNAL FREE ACCESSA 1H-NMR method has been developed for the quantitative analysis of pure cannabinoids and for cannabinoids present in Cannabis sativa plant material without any chromatographic purification. The experiment was performed by the analysis of singlets in the range of δ 4.0—7.0 in the 1H-NMR spectrum, in which distinguishable signals of each cannabinoid are shown. Quantitation was performed by calculating the relative ratio of the peak area of selected proton signals of the target compounds to the known amount of the internal standard, anthracene. For this method no reference compounds are needed. It allows rapid and simple quantitation of cannabinoids with a final analysis time of only 5 min without the need for a pre-purification step.View full abstractDownload PDF (93K) -
Mitsuteru Numazawa, Norishige Sohtome, Masao Nagaoka2004 Volume 52 Issue 6 Pages 722-726
Published: 2004
Released on J-STAGE: June 01, 2004
JOURNAL FREE ACCESSTo study the stereochemical aspects of the aromatase reaction of androst-4-en-17-one (1) and its 5-ene isomer 4, competitive inhibitors of aromatase, the [19S-3H]- and [19R-3H]-labeled 19-hydroxy derivatives 2 and 5, were synthesized through NaB3H4 reduction of the corresponding 19-aldehydes 3 and 6 as a key reaction. The hitherto unknown stereochemistry of the NaB3H4 reduction was established based on the deuterium-labeling experiments with NaB2H4. A comparison of 1H-NMR spectra of the NaB2H4 reduction products of 19-als 3 and 6 with those of the respective authentic steroids revealed that the ratios of 19S-2H to 19R-2H were 90 : 10 for the 4-ene steroid 2 and 70 : 30 for the 5-ene isomer 5, respectively. Jones oxidation of the [19S-2H]19-ols, followed by the non-labeled NaBH4 reduction, gave the corresponding [19R-2H]19-ols 2 and 5 (R-2H : S-2H=90 : 10 for steroid 2 and 70 : 30 for steroid 5). The stereoselectively 3H-labeled compounds 2 and 5 were similarly obtained in these sequences.View full abstractDownload PDF (139K) -
Shintaro Saito, Rumiko Shimazawa, Ryuichi Shirai2004 Volume 52 Issue 6 Pages 727-732
Published: 2004
Released on J-STAGE: June 01, 2004
JOURNAL FREE ACCESSSyntheses of D- and L-myo-inositol 3,4,5,6-tetrakisphosphates were achieved via diastereoselective 1,2-addition of vinylcopper reagent with the chiral aldehyde prepared from 1,2,5,6-diisopropylidene-D-glucose, ring-closing metathesis of 1,7-diene with Grubbs catalyst followed by catalytic OsO4 dihydroxylation of (+)-conduritol B derivatives.View full abstractDownload PDF (162K) -
Yoshitsugu Arai, Makoto Kasai, Yukio Masaki2004 Volume 52 Issue 6 Pages 733-738
Published: 2004
Released on J-STAGE: June 01, 2004
JOURNAL FREE ACCESSThe asymmetric conjugate addition of arylcopper reagents to chiral 1-[2-(p-tolylsulfinyl)]indolyl and 1-[3-(p-tolylsulfinyl)]indolyl enones was examined. With the 2-sulfinyl-indolyl derivatives, the reaction of the arylcopper reagent gave high diastereoselectivities (81—88% de's) to afford the adducts in excellent yields, although the similar addition reaction of the 3-sulfinyl derivatives afforded poor diastereoselectivities.View full abstractDownload PDF (140K) -
Osamu Shirota, Setsuko Sekita, Motoyoshi Satake, Hiroshi Morita, Koich ...2004 Volume 52 Issue 6 Pages 739-746
Published: 2004
Released on J-STAGE: June 01, 2004
JOURNAL FREE ACCESSNine regioisomeric and stereoisomeric triterpene dimers, namely xuxuarine Fα (1), isoxuxuarine Fα (2; cangorosin B), 7,8-dihydroisoxuxuarine Fα (3), isoxuxuarine Gβ (4), 7,8-dihydroisoxuxuarine Gα (5), isoxuxuarine Eβ (6), 7α-hydroxyisoxuxuarine Eα (7), 7′,8′-dihydroxuxuarine Aα (8), and 7′,8′-dihydroxuxuarine Dβ (9), were isolated from the Brazilian medicinal plant “xuxuá” (Maytenus chuchuhuasca). Their structures have been elucidated based on several spectroscopic analyses including 2D-NMR experiments, MS spectra and CD spectral studies.View full abstractDownload PDF (212K) -
Hideaki Fujii, Noriyuki Hirano, Hiromi Uchiro, Kuniaki Kawamura, Hiros ...2004 Volume 52 Issue 6 Pages 747-750
Published: 2004
Released on J-STAGE: June 01, 2004
JOURNAL FREE ACCESS7β-Carbamoyl-4,5α-epoxymorphinans 5 were stereoselectively synthesized from the 7α-carboxylate intermediate 3 in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) and amines under reflux conditions in mesitylene via a novel and reactive γ-lactone 7. These were the first examples of the stereoselective syntheses of 7β-substituted 4,5α-epoxymorphinans. The mechanism of the reaction process was elucidated as follows: 1) epimerization of 7α-carboxylate 3, 2) intramolecular lactonization of 7β-carboxylate 6, and 3) aminolysis of the resultant γ-lactone 7. The aminolysis of the isolated reactive γ-lactone 7 with allylamine and the alcoholysis with MeOH in the presence of NaBH4 proceeded at room temperature. The γ-lactone 7 can be a useful intermediate for the preparation of 7β-substituted 4,5α-epoxymorphinans that would be potent selective δ opioid receptor ligands. The stereoselective syntheses of the 7α-carbamoyl-4,5α-epoxymorphinans 9 from 7α-carboxylate 3 via 7α-carboxylic acid were also successful.View full abstractDownload PDF (108K) -
Junko Kawakami, Kenji Hoshi, Akiko Ishiyama, Sayaka Miyagishima, Kenic ...2004 Volume 52 Issue 6 Pages 751-755
Published: 2004
Released on J-STAGE: June 01, 2004
JOURNAL FREE ACCESSSelf-organizing map (SOM) of Kohonen seems to be a promising approach beyond the standard one to regression for some classification problems encountered in the field of pharmacy. We apply them, therefore, to the quantitative structure–activitity relationship (QSAR) in carboquinones and benzodiazepines, and show their usefulness. Most QSAR analysis using neural networks has been made by adopting neural networks with supervised learning. On the contrary, SOM obeys unsupervised learning and originally does not involve the use of desired target data. If we note that an appreciable fraction of data may be missing without making the similarity comparison impossible in SOM if the number of attributes considered is appreciable, QSAR analysis using SOM is found to be possible as if supervised learning. Similar to target data in supervised learning, we can take into account target data (=observed activity) as one of attributes in addition to other attributes (=structural descriptors). Choice of optimal descriptors as input parameters was found to be essential to generate valuable SOM.View full abstractDownload PDF (1427K) -
Iwao Okamoto, Wataru Funaki, Kyosuke Nakaya, Eiichi Kotani, Tetsuya Ta ...2004 Volume 52 Issue 6 Pages 756-759
Published: 2004
Released on J-STAGE: June 01, 2004
JOURNAL FREE ACCESSThe oxygenation reaction of cholesteryl acetate 1 was examined with the FeIII(PA)3/O2/MeCN system using an electrochemical method. The constant potential technique gave mainly the 7-hydroxylated product stereoselectively, along with the 7-oxo product. This oxygenation system is mechanistically unique, requiring iron catalyst, dioxygen, and both cathode and anode.View full abstractDownload PDF (94K)
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Thitima Rukachaisirikul, Samran Prabpai, Palangpon Kongsaeree, Apichar ...2004 Volume 52 Issue 6 Pages 760-761
Published: 2004
Released on J-STAGE: June 01, 2004
JOURNAL FREE ACCESSA new monoterpene ester, (+)-bornyl piperate was isolated from the underground roots of Piper aff. pedicellatum and its structure was elucidated on the basis of spectroscopic evidence and confirmed by X-ray analysis. The compound crystallizes in the triclinic space group P1 with a=7.3232(4) Å, b=11.4705(7) Å, c=23.2520(14) Å, V=1943.6(2) Å3. This compound showed an antituberculosis activity against Mycobacterium tuberculosis (H37Ra strain) with the minimum inhibitor concentration (MIC) of 25 μg/ml.View full abstractDownload PDF (70K) -
Shih-Chang Chien, Han-Kang Liu, Yueh-Hsiung Kuo2004 Volume 52 Issue 6 Pages 762-763
Published: 2004
Released on J-STAGE: June 01, 2004
JOURNAL FREE ACCESSTwo new compounds, 15-methoxypinusolidic acid (1) and isonerylgeraniol-18-oic acid (2) together with four knowns taiwaniaflavone (3), nerylgeraniol-18-oic acid (4), 3-(3,4-dihydroxyphenyl)-1-propanol (5), and amentoflavone (6) are isolated from the leaves of Calocedrus microlepic var. formosana. Compounds 1 and 2 were elucidated as labdane diterpene and linear diterpene, respectively, through spectral studies.View full abstractDownload PDF (66K) -
Yueh-Hsiung Kuo, Chia-Hsien Chen, Shih-Chang Chien, Hsiu-Chuan Lin2004 Volume 52 Issue 6 Pages 764-766
Published: 2004
Released on J-STAGE: June 01, 2004
JOURNAL FREE ACCESSTwo novel diterpenes, obtusanal B (1) and obtusadione (2), along with obtusanal A (3), obtunone (4), 12-hydroxy-6,7-secoabieta-8,11,13-triene-6,7-dial, 8,12-dihydroxydielmentha-5,9-diene-7,11-dione and myrcene, isolated from the heartwood of Chamaecyparis obtusa var. formosana, were characterized by spectroscopic means, including 2D-NMR techniques. Compounds 1 and 2 are 7(6→2)abeoabietane and 14(8→9)abeoabietane type diterpenes, respectively. Their biosyntheses were proposed.View full abstractDownload PDF (85K) -
Quan-Bin Han, Wei-Lie Xiao, Yun-Heng Shen, Han-Dong Sun2004 Volume 52 Issue 6 Pages 767-769
Published: 2004
Released on J-STAGE: June 01, 2004
JOURNAL FREE ACCESSFive new ent-kaurane diterpenoids xindongnins H—L (1—5), together with five known ones, xindongnins A and B (6, 7), melissoidesins G (8), dawoensin A (9), and glabcensin V (10) were isolated from Isodon rubescens var. rubescens. Their structures were elucidated by spectroscopic methods including extensive 2D NMR techniques.View full abstractDownload PDF (80K) -
Takamitsu Sasaki, Keisuke Kato, Hiroyuki Akita2004 Volume 52 Issue 6 Pages 770-771
Published: 2004
Released on J-STAGE: June 01, 2004
JOURNAL FREE ACCESSPalladium-catalyzed cyclization-methoxycarbonylation of (2R,3S)-3-methylpenta-4-yne-1,2-diol (6) derived from (2R,3S)-epoxy butanoate 5, followed by methylation, gave the tetrahydro-2-furylidene acetate (−)-7, which was converted to the left-half aldehyde (+)-3. A Wittig reaction between (+)-3 and the phosphoranylide derived from the bithiazole-type phosphonium iodide 4 using lithium bis(trimethylsilyl)amide afforded (+)-cystothiazole B (2), the spectral data of which were identical to those of the natural product (+)-2. Thus the stereochemistry of cystothiazole B (2) was confirmed to be [4R, 5S, 6(E)].View full abstractDownload PDF (74K) -
Liang Cui, Feng Qiu, Naili Wang, Xinsheng Yao2004 Volume 52 Issue 6 Pages 772-775
Published: 2004
Released on J-STAGE: June 01, 2004
JOURNAL FREE ACCESSAndrographolide is one of principal components of a famous traditional Chinese herbal medicine Andrographis paniculate (BURM) NEES. Four new metabolites of andrographolide were isolated from human urine. All of them were characterized as sulfate and one of them also as a cysteine S-conjugate. The structures were determined to be andrographolide-3-O-sulfate (M-1), isoandrographolide-3-O-sulfate (M-2), 14-deoxyandrographolide-3-O-sulfate (M-3), 14-deoxy-12-(cysteine-S-yl)-andrographolide-3-O-sulfate (M-4), respectively, based on chemical evidence and spectroscopic analyses.View full abstractDownload PDF (69K) -
Kun Wei, Wei Li, Kazuo Koike, Lijuan Liu, Xiaowen Fu, Lianbo Lin, Ying ...2004 Volume 52 Issue 6 Pages 776-779
Published: 2004
Released on J-STAGE: June 01, 2004
JOURNAL FREE ACCESSTwo new galloylglucosides, mallophenols A (1) and B (2), were isolated from the leaves of Mallotus furetianus (Euphorbiaceae), together with seven known compounds, (6S,9R)-roseoside (3), aviculin (4), (+)-lyoniresinol-3α-O-α-L-rhamnopyranoside (5), (Z)-3-hexenyl-β-D-glucopyranoside (6), 3,3,8,9,10-pentahydroxydibenzo[b,d]pyran-6-one (7), 3-hydroxy-4,5(R)-dimethyl-2(5H)-furanone (8) and gallic acid (9). The stereostructures of 1 and 2 were elucidated on the basis of spectroscopic analysis and chemical evidence.View full abstractDownload PDF (105K)
Communications to the Editor
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Yumiko Yamano, Masayoshi Ito2004 Volume 52 Issue 6 Pages 780-782
Published: 2004
Released on J-STAGE: June 01, 2004
JOURNAL FREE ACCESSThe synthesis of cucurbitaxanthin A 1 was accomplished via the C15-3,6-epoxides 7e and 7f prepared by regioselective ring opening of the 3-hydroxy-5,6-epoxides 6e and 6f.View full abstractDownload PDF (94K)
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