All issues
Volume 47, Issue 5
Displaying 1-30 of 30 articles from this issue
- |<
- <
- 1
- >
- >|
-
Fredrik HAEFFNER, Torbjorn NORIN1999 Volume 47 Issue 5 Pages 591-600
Published: May 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe use of Candida antarctica lipase B and lipases from Candida rugosa and Rhizomucor miehei for kinetic resolutions is discussed. Theories and methods for molecular modelling are presented briefly. We have studied the transition state geometry in acyl transfer reactions of serine hydrolases by ab initio calculations of proton transfer mechanisms in ester hydrolysis in order to be able to predict enantioselectivity by means of molecular modelling. A combination of molecular modelling and kinetic studies was used to construct models that explain and predict the enantioselectivity of these lipases. The calculations and the experimental results provide support for a proposal that enantiomers can bind in different orientations. Structural factors of importance for the enantioselectivity have been idenified. Our results provide information on the scope and limitations of the use of these enzymes in asymmetric synthesis. Molecular modelling also provides information about possible genetic modifications of the enzymes in order obtain a useful catalyst for a specific enantioselective transformation or for the use of the lipase framework and part of the catalytic site for the catalysis of unnatural reactions.View full abstractDownload PDF (1408K) -
Yasuyuki YOSHITAKE, Masashi ETO, Kazunobu HARANO1999 Volume 47 Issue 5 Pages 601-606
Published: May 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAn X-ray analysis of 3, 5-dimethyl-4-oxopyrazole 1, 2-dioxide (1) reveals that the N-N bond is considerably elongated [1.659(5) Å]. The bond lenght calculated by ab initio significantly varied with the change of the calculation level. The bond elongation is considered to arise from the dipole-dipole repulsion between the 〓N→O groups enhanced by the antiaromatic character of the unique ring system.View full abstractDownload PDF (692K) -
Hiromasa NAGASE, Haruhisa UEDA, Masayuki NAKAGAKI1999 Volume 47 Issue 5 Pages 607-610
Published: May 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAn examination of the relationship between the hydrophobic index of saccharide and gel-liquid crystal transition temperatures in L-α-dipalmitoly phosphatidylcholine (DPPC)/saccharide systems at a water content of 10 wt% and 70 wt% was performed using differential scanning calorimetry. Saccharide at 10 wt% water was found to interact with phospholipids hydrophobically via the hydrophobicity-rich side of the pyranose ring. Molar ratios (pyranose ring/DPPC) were determined as 2 for the DPPC/rhamnose system with 8.2 wt% water and for the DPPC/trehalose system at 15.8 wt%. Pyranose would thus appear to form a 2 : 1 complex with lipid that faces the hydrophobicity-rich side of the pyranose ring. Saccharide with 70 wt% water interacted with the phospholipid hydrophilically through hydration of the saccharide.View full abstractDownload PDF (740K) -
Prokopios MAGIATIS, Sofia MITAKU, Alexios-Leandros SKALTSOUNIS, Franco ...1999 Volume 47 Issue 5 Pages 611-614
Published: May 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSixteen new derivatives of the natural alkaloid acronycine, bearing 1-alkoxy or 1-amino and 2-hydroxy groups, were synthesized in order to clarify the role of the C-1 substitution. Studies on the cytotoxic activity of compounds 4-19 were carried out in vitro on L-1210 cells. Structure-activity relationships are discussed.View full abstractDownload PDF (736K) -
Toshiyuki HATA, Yukio ONO1999 Volume 47 Issue 5 Pages 615-620
Published: May 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSpatial distribution functions (SDFs), gOO(x, y, z) and gOH(x, y, z), which show the probability of atom-atom pair distribution between solute and solvent atoms, have been used to characterize the anisotropic structure of solutions in computer simulations. In this article, a new method for structural change analysis is proposed based on the difference spatial distribution function (DSDF) ΔgOO(x, y, z), and is applied to liquid water, and to infinitely dilute aqueous solutions of methoanol and ethanol. Based on the results of SDF in methanol and ehtanol solutions, the distribution of solvent water can be classified into three groups : hydrogen acceptor, hydrogen donor, and hydrophobic hydration regions. Regarding the effect fo hydrophobic groups, the DSDF (i.e. ΔgOO(x, y, z)=gOO(x, y, z)EtOH-gOO(x, y, z)MeOH) results indicated that the distribution volume of hydration water surrounding the alcohol molecule in the hydrogen acceptor region decreases with increasing steric bulk of the hydrophobic group. However, binding energy in this region is stabilized by an increase in the coordination number. Moreover, from the results of DSDF at 298 and 273 K (i.e. Δg<OO>(x, y, z, ΔT)=g<OO>(x, y, z, 298 K)-g<OO>(x, y, z, 273 K)), the distribution of hydration water spreads out over the region surrounding the hydrogen acceptor and donor. This result is reasonable since an increase in the fluctuation of the network structure results from a rise in temperature. The new DSDF method presented in this work should be widely applicable to structural change analysis of hydration structure for anisotropic solutions by computer siulation.View full abstractDownload PDF (916K) -
Chiristian F. MASAGUER, Isabel CASARIEGO, Enrique RAVINA1999 Volume 47 Issue 5 Pages 621-632
Published: May 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWe describe the synthesis of 5-aminoethyl- and 6-aminomethyl-4-oxotetrahydroindoles as butyrophenone derivatives in the indole series, as potential atypical antipsychotics. The affinities of these compounds for serotonin (5-HT2A) and dopamine (D2) receptors were evaluated in vitro. The ratios of pKi's for 5-HT2A/D2 receptors may be useful for rapid screening of new compounds and assessing potential induction of extrapyramidal symptoms; ratio values ≥1.12 (Meltzer's ratio) are predictive of an atypical antipsychotic profile. Compounds 26e (QF 0408B) and 26f (QF 0409B) showed high affinity for both D2 and 5-HT2A receptors, and their MEltzer's ratios were 1.32 and 1.17 respectively, while haloperidol showed a ratio of 0.93.View full abstractDownload PDF (1777K) -
Paul Wan Sia HENG, Tin Wui WONG, Jian Jun SHU, Lucy Sai Cheong WAN1999 Volume 47 Issue 5 Pages 633-638
Published: May 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe control of the melt pelletization process in an 8-1 high shear mixer using specific energy consumption of the impeller motor was studied. Lactose was used as the bulk material with polyethylene glycol 3000 as a meltable binder. The effects of binder concentration, mean particle size of bulk material and post-melt impeller speed on the relationship of specific energy consumption and pellet growth were examined. Specific energy consumption was found to be a suitable tool for monitoring the melt pelletization process, and specific energy consumption correlated well with pellet growth. The mean size of the pellets formed becomes correspondingly larger with increasing specific energy consumption. Concerning the impeller speed, specific energy consumption is more useful as a tool for end-point control of the process than post-melt mixing time. Similar size pellets can be obtained with comparable specific energy consumption, independent of the impeller speed. The control of pellet size requires a correlation between pellet growth and specific energy consumption that is established for the formulaiton and process conditions used. For this purpose, mathematical modelling of the pellet growth process is presented. The predictions of pellet growth by the mathematical model are in agreement with the experimental findings.View full abstractDownload PDF (747K) -
Junichi KITAJIMA, Yoshie AOKI, Toru ISHIKAWA, Yasuko TANAKA1999 Volume 47 Issue 5 Pages 639-642
Published: May 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFour new monoterpenoid glucosides were isolated from the methanolic extract of the fruit of Cnidium monnieri CUSSON (Umbelliferae) together with four known glucosides of aromatic compounds. Their structures were clarified by spectral investigation.View full abstractDownload PDF (549K) -
Ambroise POUMAROUX, Zouhair BOUAZIZ, Houda FILLION, Monique DOMARD, Jo ...1999 Volume 47 Issue 5 Pages 643-646
Published: May 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSHetero Diels-Alder reactions between 2- or 3-bromocarbazolequinones 1a or 1b and azadiene 5 afford regiospecifically pylrido[3, 4-b]- and pyrido[4, 3-b]carbazole-3, 5, 11-triones 6a and 6b. The regiochemistry of the cycloadditions is controlled by the position of the bromine atom at C-2 or C-3 of the bromoquinone. The corresponding N- and O-methyl derivatives 7 and 8 are prepared. Structural assignment of the regioisomers is made by 1H-NMR unclear Overhauser effect difference experiments performed on a diacetoxy derivative of pyrido[4, 3-b]carbazole 9b. The in vitro antifungal and antiprotozoological activities of some prepared derivatives have been evaluated against Candida albicans, Candida krusei, Cryptococcus neoformans and Trichomonas vaginalis. None of the tested compounds have shown significant activity towards the yeasts or protozoa.View full abstractDownload PDF (624K) -
Naoyoshi KOBAYASHI, Izumi SAITOH1999 Volume 47 Issue 5 Pages 647-651
Published: May 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA study was carried out with a liquid droplet dispersion system ointment (LDDS) using mometasone furoate as the drug and ethyleneglycol salicylate as the solvent. First, drug concentrations in the bleeding liquid (CBL) and in the liquid droplet (Cs) were determined. It was suggested that a partition equilibrium is established between the two.Next, an in vitro drug release test was performed. A slope obtained from plotting the cumulative amount of the drug released against the square root of time was used as an index of release. With changes in the drug concentration in ointment (Co) at a definite solvent concentration in ointment (So), Co was proportional to the slope. The result predicted from CBL based on the theory of thermodynamic activity corresponded with that of the actual in vitro drug release. On the other hand, with changes in So at definite Co, the slope remained nearly constant, regardless of changes in So. The result predicted from C<BL> based on the theory of thermodynamic activity did not correspond with that of the actual in vitro drug release.Thus, further studies from various theoretical aspects were done. It was confirmed that a proposed equation for LDDS can be put in order similar to ones either for a soluble type or a crystal dispersion type. In this process, the volume fraction of the liquid droplet phase was suggested to be an important parameter for LDDS. Further, good correlation between the found values and the proposed equation was noted. Therefore, the validity of the proposed equation was verified.View full abstractDownload PDF (757K) -
Hsiou-Yu DING, Yang-Chang WU, Hang-Ching LIN, Yu-Yi CHAN, Pei-Lin WU, ...1999 Volume 47 Issue 5 Pages 652-655
Published: May 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFour new glycosides, namely mudanpiosides-G, -H, -I and mudanoside-A together with three known compounds, gallic acid, adenosine and p-hydroxybenzoic acid were isolated from the root bark of Paeonia suffruticosa. Their structures have been determined on the basis of spectral evidence.View full abstractDownload PDF (544K) -
Shuichi JONOSHITA, Atsuhiro HARADA, Masaaki OMOTE, Akira ANDO, Itsumar ...1999 Volume 47 Issue 5 Pages 656-662
Published: May 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSN-Tosyltrifluoroacetaldehyde imine (4) reacted with terminal olefins by only heating together to give the ene reactin products. This means the imine is much more reactive than trifluoroacetaldehyde (2) itself as an enophile. However, 4 was very sensitive to moisture and the yields were low even if it was used without isolation. Further, it did not react with non-terminal olefins. In the course on study of the mechanism of this reaction, we found that N-(2, 2, 2-trifluoro-1-ethoxyethyl)tosylamide (12), obtained by the reaction of trifluoroacetaldehyde ethyl hemiacetal (1) with tosylamide (3) in the presence of titanium(IV) chloride followed by addition of ethanol, reacted in the presence of sodium hydride and titanium(IV) chloride to give the same products from the ene reaction of 4 in much better yields. Interestingly, this reaction proceeded with non-terminal olefins.View full abstractDownload PDF (1050K) -
Masao KIKUCHI, Noriko KAWARADA, Yasunori YAOITA1999 Volume 47 Issue 5 Pages 663-666
Published: May 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFive new fernane type triterpenoids, ferna-7, 9(11)-diene-3α, 16α-diol (1), 3α, 16α-dihydroxyferna-7, 9(11)-dien-12-one (2), ferna-7, 9(11)-diene-3α, 16α, 19α-triol (3), 3α, 16α-dihydroxyfern-8-en-11-one (4) and 3α, 16α-dihydroxyfern-8-ene-7, 11-dione (5), were isolated from the leaves of Lonicera gracilipes var. glandulosa MAXIM. The structures of these compounds were elucidated on the basis of spectroscopic evidence.View full abstractDownload PDF (627K) -
Makoto HASHIMOTO, Yasumaru HATANAKA1999 Volume 47 Issue 5 Pages 667-671
Published: May 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWe successfully applied a carbene-generating N-acetylglucosamine derivative carrying a biotinyl group to the radioisotope-free identification of peptides within bovine UDP-galactose : N-acetylglucosamine β1, 4-galactosyltransferase (GalT, EC 2.4.1.38) catalytic domain. Owing to the low yield of cross-linking, conventional photoaffinity labeling experiments usually encounter a thorny problem in attemptin to isolate labeled components from very complex mixtures. A biotion tag introduced with our photoaffinity probe enabled us to separate the photolabeled protein from a large amount of coexisting unlabeled GalT. The introduction of biotin was also useful for the radioisotope-free detection of a labeled protein based on a highly sensitive chemiluminescent technique. We developed a novel poly(vinylidene difluoride) membrane for the identification of labeled peptides in a simple dot blot assay. Using this membrane, we successfully identified biotinyl peptides among a number of HPLC separated fragments derived from the protease digestion of photolabeled GalT proteins. The sequence analysis revealed that the biotin tag was incorporated within a tryptic GalT fragment of Y197-R208. Our approach yields, for the first time, information on the acceptor substrate binding-site fragment in this enzyme, that has been difficult to obtain using other approaches. These data are consistent with previous suggestions concerning the GalT acceptor site and clearly demonstrate the effectiveness of our approach for rapid identification of photolabeled peptides.View full abstractDownload PDF (822K) -
Toshihiro WATANABE, Isao KINOYAMA, Kenji TAKIZAWA, Seiko HIRANO, Tadao ...1999 Volume 47 Issue 5 Pages 672-677
Published: May 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA series of 1, 2, 3, 4-tetrahydroisoquinoline derivatives containing the 5, 11-dihydro-6H-pyrido[2, 3-b][1, 4]benzodiazepin-6-one skeleton were prepared and evaluated for their in vitro binding affinities to muscarinic receptors and for antagonism of bradycardia in vivo. Among them, compound 3f had the highest affinity for M2 muscarinic receptors in the heart (pKi=9.1) with low affinity for M3 muscarinic receptors in the submandibular gland. A structure-activity relationship (SAR) study suggested that the benzene ring fused piperidine and the alkyl linker chain lenght are crucially important for increased M2 affinity.View full abstractDownload PDF (970K) -
Isao YOSHIDA, Yoshimichi SAKAI1999 Volume 47 Issue 5 Pages 678-683
Published: May 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe new criteria for the weight variation test and the content uniformity test in general tests were revised in the Japanese Pharmacopoeia thirteenth edition (JPXIII), and both tests are used to determine the uniformity of dosage units. The weight variation test, if the content of an ingredient could be directed in the assay reported in JP13, replaces the content uniformity test. Although over-the-counter (OTC) drugs, for example medicine for coughs, are guaranteed to content uniformity, the applications of these tests have not been thoroughly investigated.We investigated whether one of the effective ingredients could be used as an indicator for the content uniformity of an OTC drug. The indicator was chosen by reason of the very small quantity compared to the others such as anhydrous caffeine in the case of cough medicine. When the mixing process was incomplete and the weight variation test was passed, the content uniformity of anhydrous caffeine in tablet varied in relative standard deviation and could not be guaranteed by this test, though both tests were passed as to the other ingredients. One ingredient such as anhydrous caffeine could not be used as arepresentative indicator for the other ingredients to confirm the content uniformity. And the content uniformity test could not be replaced by the weight variation test when the content uniformity of the mixed powder had not been confirmed. To guarantee the content uniformities of all effective ingredients of OTC drugs, the content uniformities in the mixing process should be confirmed respectively.View full abstractDownload PDF (890K) -
Tetsuya YABUUCHI, Takenori KUSUMI1999 Volume 47 Issue 5 Pages 684-686
Published: May 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSeveral α-methoxy- and α-hydroxycarboxylic acids have been synthesized by a new one-pot synthesis using ketones, tribromomethane, and potassium hydroxide in methanol and water, respectively, in good yields.View full abstractDownload PDF (452K) -
kazuyoshi ARAO, Masanori INAGAKI, Ryuichi HIGUCHI1999 Volume 47 Issue 5 Pages 687-689
Published: May 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAn inositolphosphoceramide molecular species, tentatively named CJP1, has been obtained from the feather star Comanthus japonica, which belong to the class of crinoidea of phylum echinodermata of deuterostomia. On the basis of chemical and spectroscopic evidence, the structure of CJP1 was determined as D-myo-inositol-1-O-phosphoceramide, which contained a C16 : 1 sphingosine and a C22 : 0, C24 : 0 normal fatty acid. The same type of sphingolipid has been obtained from plants and protostomia but not yet from deuterostomia. This is the first report on the isolation and structure elucidation of inositolphosphoceramide from deuterostomia.View full abstractDownload PDF (473K) -
Keisuke KOJIMA, Kimio ISAKA, Ondognii PUREV, Gonbovanjilin JARGALSAIKH ...1999 Volume 47 Issue 5 Pages 690-691
Published: May 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new farnesyl-benzofuranone type sesquiterpenoid derivative, 2, 6-dihydroxy-2-[3, 7, 11-trimethyl-2(E), 6(E), 10-dodecatrien-1-yl]-3(2H)-benzofuranone was isolated from the roots of Ferula ferulioides. The structure was established by comprehensive spectral analysis.View full abstractDownload PDF (351K) -
Koichi MACHIDA, Masao KIKUCHI1999 Volume 47 Issue 5 Pages 692-694
Published: May 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSix new triterpenoids, viburnudienone B1 methyl ester (1), viburnudienone B2 methyl ester (2), viburnudienone H1 (3), viburnudienone H2 (4), viburnenone B1 methyl ester (5) and viburnenone B2 methyl ester (6), were isolated from the leaves of Viburnum dilatatum (Caprifoliaceae). Their structures were established by extensive spectroscopic studies.View full abstractDownload PDF (457K) -
Hirotaka SHIBUYA, Takako BOHGAKI, Toshiyuki MATSUBARA, Michiyo WATARAI ...1999 Volume 47 Issue 5 Pages 695-698
Published: May 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo new isopimarane-type diterpenes named orthosiphonones A and B and a new benzochromene named orthochromene A, have been isolated from the water decoction of the leaves of Orthosiphon aristatus (Lamiaceae) collected in Java, Indonesia. Their chemical structures have been elucidated on the basis of physicochemical and chemical evidence.View full abstractDownload PDF (646K) -
Yasuyuki ENDO, Kyoko YAGUCHI, Motonori TSUJI, Kentaro YAMAGUCHI, Koich ...1999 Volume 47 Issue 5 Pages 699-701
Published: May 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe preparation and reactivity of poly-B-methyl-1, 12-dicarba-closo-dodecaborane (poly-B-methyl-p-carborane) derivatives are described. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11-Decamethyl-1, 12-dicarba-closo-dodecaborane(12)-1-carboxylic acid was prepared from 2, 3, 4, 5, 6, 7, 8, 9, 10, 11-decamethyl-1, 12-decarba-closo-dodecaborane(12) by lithiation with methyllithium, followed by carboxylaiton. Conversion of the carboxylic acid into its ester and amide were achieved through its acyl chloride. The ester and the amide could not be hydrolyzed due to severe steric hindrance around the carbonyl group of the molecules owing to the adjacent B-methyl groups.View full abstractDownload PDF (529K) -
Yasuyuki ASAI, Sumio WATANABE1999 Volume 47 Issue 5 Pages 702-704
Published: May 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe effects of menaquinone-4 (MQ) on dipalmitoylphosphatidylcholine (DPPC) membranes were studied by surface monolayer and fluorescence techniques. DPPC and MQ have been proven to be freely miscible in the mixed monolayer at an air/water interface, and to be partially miscible in a bulk phase, i.e., the bilayer and solid phase. There is an expanding interaction between MQ and DPPC in the MQ/DPPC mixed monolayer. The solubility of MQ in the DPPC is about 20 mol%, and the solubility of DPPC in MQ is about 10 mol%. The addition of MQ induced a proportional decrease in the phase transition temperature of DPPC membrane and a broadening of the temperature range of the transition.View full abstractDownload PDF (495K) -
Yasunori YAOITA, Hirokazu KAMAZAWA, Masao KIKUCHI1999 Volume 47 Issue 5 Pages 705-707
Published: May 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFive new oplopane-type sesquiterpenoids, 7β-senecioyloxyoplopa-3(14)Z, 8(10)-dien-2-one (1), 7β-angeloyloxyoplopa-3(14)Z, 8(10)-dien-2-one (2), 7β-(4-methylsenecioyloxy)oplopa-3(14)E, 8(10)-dien-2-one (3), 1α-angeloyloxy-7β-(4-methylsenecioyloxy)oplopa-3(14)Z, 8(10)-dien-2-one (4) and 1α, 7β-di(4-methylsenecioyloxy)oplopa-3(14)Z, 8(10)-dien-2-one (5), were isolated from the flower buds of Tussilago farfara L. (Compositae). The structures of these compounds were elucidated on the basis of spectroscopic evidence.View full abstractDownload PDF (504K) -
Junei KINJO, Katsuya AOKI, Masafumi OKAWA, Yuichi SHII, Tomoki HIRAKAW ...1999 Volume 47 Issue 5 Pages 708-710
Published: May 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIn order to confirm the constitution of hepatoprotective oleanene glucuronide (OG), HPLC profile analyses of the total OG fractions of both Puerariae Thomsonii Flos (the flowers of Pueraria thomsonii) and Puerariae Lobatae Flos (the flowers of P. lobata) were performed. No remarkable difference in the HPLC profiles with respect to OGs in the flowers was shown, in contrast to those of the roots. By repeated chromatography of the total OG fraction of Puerariae Thomsonii Flos, soyasaponin I (1), kaikasaponin III (2) and kakkasaponin I (3), which had been already isolated from Puerariae Lobatae Flos, were obtained. The hepatoprotective activity of 2 towards immunologically induced liver injury was significantly more effective than that of 1. This information supported previously obtained structure-hepatoprotective relationship data which was measured on another model. The structure-activity relationship information which suggested that the hydroxymethyl group of the galactosyl unit would enhance the hepatoprotective activity was also substantiated.View full abstractDownload PDF (459K) -
Katsuhiro KONNO, Shojiro MAKI, Hiroaki TAKAYAMA1999 Volume 47 Issue 5 Pages 711-712
Published: May 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSDownload PDF (446K) -
Masahiko TANIGUCHI, Yong-Qing XIAO, Xiao-Hong LIU, Akiko YABU, Yousuke ...1999 Volume 47 Issue 5 Pages 713-715
Published: May 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo new condensed furanocoumarins, the dimer rivulobirin E and the trimer rivulotririn C (1 and 2) were isolated from the underground part of Pleurospermum rivulorum (Umbelliferae) and their structures established spectral means.View full abstractDownload PDF (363K) -
Toshihiro HASHIMOTO, Yoshiaki NOMA, Sumie KATO, Masami TANAKA, Shigeru ...1999 Volume 47 Issue 5 Pages 716-717
Published: May 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSBiotransformation of the sesquiterpene alcohol hinesol (1) with spasmolytic activity, which was prepared from the rhizome of Atractylodes lancea, was carried out by Aspergillus niger and Aspergillus cellulosae IFO 4040. Compound 1 was easily converted to compounds 2-9 by A. niger, and compounds 10 and 11 by A. cellulosae, respectively. Their stereostructures were established by a combination of high -resolution NMR spectral analysis, X-ray crystallographic analysis, and chemical reactions such as epoxydation.View full abstractDownload PDF (410K) -
Masami KAWASE, Jyunichi KOYANAGI, Setsuo SAITO1999 Volume 47 Issue 5 Pages 718-719
Published: May 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTrifluoroacetyl pyridine derivatives are conveniently prepared and applied to the synthesis of trifluoromethyl-substituted pyrazolo[4, 3-c]pyridine derivatives.View full abstractDownload PDF (355K) -
Takeshi KAMBARA, Kiyoshi TOMIOKA1999 Volume 47 Issue 5 Pages 720-721
Published: May 15, 1999
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSReaction of a lithium ester enolate with benzaldehyde anisidine-imine was catalyzed by a catalytic amount of bisoxazoline ligand to afford the corresponding β-lactam in higher ee than that obtained by the reaction using a stoichiometric amount of the ligand. Investigation of the varying factors suggested the involvement of steric factors.View full abstractDownload PDF (351K)
- |<
- <
- 1
- >
- >|