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Volume 39, Issue 8
Displaying 1-50 of 59 articles from this issue
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Keiko TANAKA, Tokuji TAKEDA, Koichiro MIYAJIMA1991 Volume 39 Issue 8 Pages 1917-1921
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe heating thermograms of differential scanning calorimetry (DSC) on the binary and three component systems, saccharide/water, dipalmitoylphosphatidylcholine (DPPC)/water and saccharide/DPPC/water, were investigated at various compositions from -120°C to 40°C. Maltose and glucose were used as saccharids. The thermograms of the saccharide/DPPC/water system were very similar to those of the saccharide/water system. The average amount of unfreezable water per molecule in the ternary system was found to be simply an arithmetic average of those of the binary systems. The solid-liquid state diagram of saccharide and water in the DPPC/saccharide/water system was analyzed. Based on these results, no direct interaction between the saccharide molecules and DPPC molecules in the frozen state was concluded. The saccharides were found to raise the gel-liquid-crystalline phase transition temperatures of the hydrated multilamellar of DPPC, and its mechanism was proposed to be a water-mediated interaction.View full abstractDownload PDF (751K) -
Ichiro ISHIKAWA, Tsuneo ITOH, Hiroaki TAKAYANAGI, Jun-ichi OSHIMA, Nor ...1991 Volume 39 Issue 8 Pages 1922-1930
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe photochemical reactions of uracil and 5-fluorouracil derivatives with simple alkenes have been investigated. Photocycloaddition of uracil or 5-fluorouracil derivatives and 2, 3-dimethyl-2-butene in acetone gave an enantiomeric mixture of cross cycloadducts (4, 7) in moderate yields. Under similar conditions, diastereomers of 4-substituted 7, 7, 8, 8-tetramethyl-cis-2, 4-diazabicyclo[4.2.0]octane-3, 5-dione nucleosides (14-17) were formed from uridine or 5-fluorouridine derivatives in good yields. The structures and stereochemistry of these cycloadducts of the nucleoside series were elucidated on the basis of the proton nuclear magnetic resonance spectra and X-ray crystallographic analysis.View full abstractDownload PDF (1316K) -
Makoto SUNAGAWA, Haruki MATSUMURA, Masao ENOMOTO, Takaaki INOUE, AKira ...1991 Volume 39 Issue 8 Pages 1931-1938
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA highly efficient synthesis of(3R, 4R)-4-acetoxy-3-[(R)-1-hydroxyethyl]-2-azetidinone, which is a key intermediate for the synthesis of carbapenem and penem antibiotics, was accomplished. It was found that oxymercuration-reduction of easily obtainable 4-alkyloxycarbonyl-1-(di-p-anisylmetyl)-3-ethenyl-2-azetidinone could be employed as a key stereoselective reaction. The chiral starting material was obtained by optical resolution or asymmetric (2+2) cycloaddition. The desired product was afforded in four steps, that is, oxymercuration-reduction, oxidative decarboxylation, protection of the hydroxy group and removal of the N-protecting group.View full abstractDownload PDF (1128K) -
Tsuneo IWAKAWA, Hiroto TAMURA, Akira MURABAYASHI, Yoshio HAYASE1991 Volume 39 Issue 8 Pages 1939-1943
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA novel, one-pot synthesis of 3-dimethylamino-4, 1, 2-benzoxathiazine 1, 1-dioxides (7), 3-methoxy-4-methyl-1, 2, 4-benzothiadiazine 1, 1-dioxide (9) and 3-dimethylamino-1, 4, 2-benzodithiazine 1, 1-dioxides (11) is described. The procedure in the case of 7 involves [2+2] cycloaddition reaction of chlorosulfonyl isocyanate (CSI) with thiocarbamates with subsequent loss of carbonyl sulfide, followed by cyclization of the resulting N-chlorosulfonyl isothioureas under Friedel-Crafts conditions. Synthesis of 9 was achieved similarly. Also, by using dithiocarbamates instead of thiocarbamates, the 1, 4, 2-benzodithiazines 11 were synthesized.View full abstractDownload PDF (706K) -
Dong-Ung LEE, Kinuko IWASA, Miyoko KAMIGAUCHI, Narao TAKAO, Wolfgang W ...1991 Volume 39 Issue 8 Pages 1944-1948
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTreatment of phthalideisoquinolines such as α- (1) and β-narcotine (2) as well as β- (3) and α-hydrastine (4) with ethyl chloroformate (ECF) at room temperature afforded, via the chloro-carbamates, the corresponding diastereomeric carbinols with high stereoselectivity. Instrumental analyses of each diastereomeric pair indicate that the major isomers derived from α- and β-narcotine as well as from α- and β-hydrastine are enantiomers of each other. The absolute configuration of the major carbinol 6a from α-narcotine (1) was determined by X-ray analysis. The probable difference between the reaction course of α-and β-narcotine is discussed. On the other hand, treatment of α-narcotine with ECF under reflux furnished Z-(8) and E-(9) enol lactones, while only the Z-isomer 12 could be isolated from the degradation of β-hydrastine (3) even at room temperature.View full abstractDownload PDF (764K) -
Akikazu KAKEHI, Suketaka ITO, Tosio SAKURAI, Kunio URUSHIDO1991 Volume 39 Issue 8 Pages 1949-1951
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSingle crystal X-ray analyses of thieno[3, 2-a]- and thieno[2, 3-b]indolizine derivatives were carried out and their structures were definitively established. The tricyclic ring systems in both molecules were nearly planar and their deviations from the least-squares planes were less than 6.26°. The structural factors for their indolizine moieties were very similar to those for known aromatic indolizines, but those for the thiophene rings were somewhat different. The deviation from co-planarity and the deformation of the thiophene ring in thieno[3, 2-a]indolizine were greater than those in thieno[2, 3-b]indolizine.View full abstractDownload PDF (549K) -
Kazunobu HARANO, Hideo KIYONAGA, Chiaki YOKOTE, Takuzo HISANO1991 Volume 39 Issue 8 Pages 1952-1957
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSO-Cinnamyl and O-(2-methylthioethyl) S-methyl dithiocarbonates (xanthates) underwent thione-thiol rearrangement to the dithiol esters in various solvents. The reactions followed first-order kinetics and the rates were affected by change of the solvent polarity. Plots of the rate constants against the Y values showed good linear relationships. The rate constants may be used as a new empirical parameter of solvent polarity in place of Y values. Modified intermediate neglect of differential overlap (MINDO/3) calculations indicate that allylic xanthates undergo [3, 3]-sigmatropic rearrangement via a polarizable transition state.View full abstractDownload PDF (836K) -
Haruhiro FUJIMOTO, Kaijiro MAEDA, Mikio YAMAZAKI1991 Volume 39 Issue 8 Pages 1958-1961
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThree new triterpene glycosides, hebevinosides XII, XIII and XIV, were isolated besides five already known neurotoxic hebevinosides from acetone extract of the mycelium with primordia of a poisonous mushroom, Hebeloma vinosophyllum, and their structures were deduced to be 3β, 7β, 16β-trihydroxycucurbita-5, 24-diene-3-O-β-D-xylopy-ranoside-16-O-(4-O-acetyl)-β-D-glucopyranoside, 3β, 7β, 16β-trihydroxycucurbita-5, 24-diene-3-O-(3, 4-di-O-acetyl)-β-D-xylopyranoside-16-O-(4, 6-di-O-acetyl)-β-D-glucopyranoside and 3β, 7β, 16β-trihydroxycucurbita-5, 24-diene-3-O-(3, 4-di-O-acetyl)-β-D-xylopyranoside-16-O-(6-O-acytyl)-β-D-glucopyranoside, respectively.Productivity of the eight hebevinosides was studied at three growth stages of the organism; mycelium (stage I), mycelium with primordia (stage II) and mycelium with fruit-bodies (stage III). The ratio of production of total hebevinosides at stages I : II : III was approximately 6 : 4 : 25. Production of hebevinosides VII, XIV, XIII, VIII and XII having the acetyl groups at O-4 in the glucosyl and/or O-3 in the xylosyl moieties, which are comparatively labile, decreased, and that of hebevinosides III and II having the acetyl groups at O-6 in the glucosyl and/or O-4 in the xylosyl moieties, which are relatively stable, increased in the time course from stage I to stage III. On the other hand, production of hebevinoside VI having no acetyl group was independent of the growth stages. Production of ergostane-type sterols seemed to be activated for the first time at stage III in the organism.View full abstractDownload PDF (762K) -
Nobutoshi MURAKAMI, Takahiro TANASE, Shin-ichi NAGAI, Yuichi SATO, Tai ...1991 Volume 39 Issue 8 Pages 1962-1966
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe Diels-Alder reactions of a cardiac glycoside, proscillaridin (1), with some dienophiles were investigated. The reaction of 1 with alkenes such as methyl vinyl ketone and methyl acrylate afforded 3-oxo-2-oxabicyclo[2.2.2]oct-7-enes (2-5) and para-substituted benzene derivatives (6 and 7), while 1 reacted with alkynes (3-butyn-2-one, methyl propiolate) to yield para- or meta-substituted benzene derivatives (6-9). The biological activities of the resulting derivatives were evaluated by the use of isolated guinea-pig papillary muscle preparations and Na+, K+-adenosine triphosphatease (ATPase) preparation from dog kidney. Among the proscillaridin derivatives, compounds 4 and 7 moderately inhibited Na+, K+-ATPase activity. Furthermore, the concentration range of 7 over which its positive inotropic effect on guinea-pig papillary muscle preparations, increased from 5% to 95% of maximum was broader than that of 1, i.e., concentration dependency was maintained over a greater range of concentration.View full abstractDownload PDF (845K) -
Akira ANDO, Toshiaki TATEMATSU, Takayuki SHIOIRI1991 Volume 39 Issue 8 Pages 1967-1971
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSReaction conditions for the enantioselective aldol reaction of 2, 2-dimethyl-3-pentanone (3) and benzaldehyde using the chiral lithium amide 1b as a chiral auxiliary were thoroughly investigated. All three procedures, that is, (1) the combined use of lithium diisopropylamide and the chiral lithium amide 1b, (2) the use of an excess of the chiral lithium amide 1b, and (3) the regeneration of the chiral lithium amide 1b, afforded the aldol 4 in about 90% yield and 70% enantiomeric excess (ee). Investigation of the effects of solvent by utilizing 1-naphthaldehyde revealed that in tetrahydrofuran, (S, S)-aldol 5 of 77% ee was obtained as the major product, while in ether (R, R)-5 became the major isomer (38% ee). Furthermore, addition of hexamethylphosphoric triamide caused a dramatic change of stereoselectivity, and (S, S)-5 of 70% ee was obtained in ether with 20 eq of hexamethylphosphoric triamid. The aldol 4 of 74% ee was obtained when the new chiral lithium amide 6b was used.View full abstractDownload PDF (809K) -
Nobuo NAGASHIMA, Masaji OHNO1991 Volume 39 Issue 8 Pages 1972-1982
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFluoride anion was found to promote monoalkylation reaction of diols by the stannylene acetal method, and selective monoalkylation of various acyclic diols was accomplished in good yields under mild conditions by employing this new method. Functional groups such as carboxylic acid ester, carboxamide, carbamate, nitrile, alkyl chloride, and ether were not affected under the reaction conditions.View full abstractDownload PDF (1599K) -
Yoshisuke TSUDA, Makoto NISHIMURA, Yoko ITO1991 Volume 39 Issue 8 Pages 1983-1989
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSLithium aluminum hydride reduction of glycopyranoside-monotosylates caused three reactions : (1) stereospecific 1, 2-shift, producing branched furanosides (path A), (2) reductive O-S bond cleavage, producing the original glycosides (path B), and (3) reductive removal of the tosyloxy group, producing deoxyglycosides (path C). The path A reaction was particularly evident for the monotosylates at 2-O, 3-O, and 4-O : for example, methyl 2-O-tosyl-α-D-xylopyranoside gave methyl 2-deoxy-2-C-(hydroxymethyl)-α-D-erythrofuranoside in 60% yield. This reaction opens a new and efficient route to branched glycofuranosides of natural and unnatural type. Stereo-electronic requirements of this reaction in relation to the balance of the other two reactions are discussed.View full abstractDownload PDF (1059K) -
Brenda MESTER, Rosa M. CLARAMUNT, Jose ELGUERO, Juan ATIENZA, Alicia G ...1991 Volume 39 Issue 8 Pages 1990-1993
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA series of ten 1-[(5-nitrothenylidene)amino]azoles has been synthesized by the reaction of 5-nitrothiophene-2-carbaldehyde with 1-aminopyrazole, 1-aminoimidazole, 1- and 4- amino-1, 2, 4-triazoles, 1-aminoindole, 1- and 2-aminoindazoles, 1-aminobenzimidazole and 1- and 2-aminobenzotriazoles. Physical data, spectroscopic characteristics and biological properties of all the derivatives have been examined. The antiprotozoal activity has been tested against Trypanosoma cruzi, comparative to Nifurtimox (Lampit).View full abstractDownload PDF (596K) -
Tsuneo KUSAMA, Tsunehiko SOGA, Yoshiyuki ONO, Eiji KUMAZAWA, Emiko SHI ...1991 Volume 39 Issue 8 Pages 1994-1999
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo novel analogs of a biosynthetic precursor of lipid A (2) were synthesized. The one analog (3) has acyl groups identical to those of 2, and the other (4) has tetradecanoyl groups in place of the (R)-3-hydroxytetradecanoyl groups of 2. Both 3 and 4 possess an α-glycosidically-bound phosphonooxyethyl group in place of the α-glycosyl phosphate group of 2.Compounds 3 and 4 exhibited definite antitumor activity against Meth A fibrosarcoma and low toxicity in rabbits, as the original compound 2 does. The replacement of the hydroxytetradecanoyl groups with tetradecanoyl groups barely affected the antitumor activity, but slightly enhanced the toxicity in rabbits.View full abstractDownload PDF (985K) -
Takaaki HIRANO, Kazuta OGURI, Hidetoshi YOSHIMURA1991 Volume 39 Issue 8 Pages 2000-2004
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThree pairs of N-substituted normorphine derivatives and the sulfate conjugates at the 6-position were tested for the analgesic and antagonistic activities and the development of physical dependence in mice. The compounds examined were nalorphine, nalorphine-6-sulfate (N-6-S), N-cyclopropylmethylnormorphine (CPN), N-cyclopropylmethylnormorphine-6-sulfate (C-6-S), N-dimethylallylnormorphine (DMN) and N-dimethylallylnormorphine-6-sulfate (D-6-S). The latter two pairs were newly synthesized. The analgesic activity of C-6-S and D-6-S was equipotent to that of CPN and DMN by the acetic acid writhing test on the s.c. injection, and the activity of N-6-S was about 2 times more potent than that of nalorphine. The antagonistic activity of N-6-S, C-6-S and D-6-S to morphine analgesia was higher than that of the parent compounds by the tail pinch test on i.c.v. injection. A withdrawal sign was seen in mice treated chronically with CPN, C-6-S and N-6-S by challenge with naloxone, whereas the mice treated with DMN, D-6-S and nalorphine showed no such sign. The effect of sulfation at the 6-position on the development of physical dependence was not well associated with the effect on agonistic and antagonistic activities.View full abstractDownload PDF (796K) -
Yoshiharu MINAMITAKE, Yasuo KITAJIMA, Mayumi FURUYA, Maki YOSHIDA, Sho ...1991 Volume 39 Issue 8 Pages 2005-2008
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTo determine whether the addition of a methylene unit in the side chain of the Asp or Arg residue in α-human atrial natriuretic peptide (α-hANP) influences its biological activity, analogs of α-hANP, [Glu13]-α-hANP (7-28) (1), [Aad13]-α-hANP (7-28) (2), and [Harn]-α-hANP(7-28) (where n is any possible combination of 11, 14 and 27) (3-9), where the original Asp or Arg residue was replaced by a homo-amino acid, were synthesized by the solid-phase synthesis method. All the analogs were evaluated for their receptor binding, cyclic guanosine monophosphate (cGMP) accumulation activity in rat vascular smooth muscle cells (VSMC), and for vasorelaxant activity employing rat aorta. 1 and 2 were 0.9 and 0.03 times as potent as α-hANP (7-28), respectively, in binding. Har-containing analogs (3-9) were as potent as α-hANP (7-28) in binding. Among the Har-containing analogs, [Har11, 14]-α-hANP (7-28) (6) and [Har11, 27]-α-hANP (7-28) (7) were remarkably vasorelaxant active, being 4.2 and 5.3 times potent than α-hANP (7-28), respectively, in spite of relatively lower cGMP accumulation activity in the case of 7. The roles of the chargeable amino acid residues in biological activity are discussed.View full abstractDownload PDF (701K) -
Yukuo EGUCHI, Yuko SATO, Satomi SEKIZAKI, Masayuki ISHIKAWA1991 Volume 39 Issue 8 Pages 2009-2015
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS4-Aryl derivatives of 7-ethoxycarbonyl-6, 8-dimethyl-1(2H)-phthalazinone and related derivatives were newly synthesized in order to test for their inhibitory activities on platelet aggregation. 4-(2-Anisyl) compound and the corresponding 1-chloro derivative demonstrated significant activity.View full abstractDownload PDF (985K) -
Naoki SAKURA, Satoru OHTA, Yoshiki UCHIDA, Katsuro KUROSAWA, Keiko OKI ...1991 Volume 39 Issue 8 Pages 2016-2020
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSRat neuromedin U (r-NMU) and its fragment peptide amides were synthesized by solid-phase methodology. Using a chicken crop smooth muscle contraction assay, the potency of r-NMU and its fragments relative to porcine neuromedin U-8 (p-NMU-8) was r-NMU : 10.25±2.88, r-NMU (6-23) : 8.01±1.04, r-NMU (10-23) : 2.76±0.46, r-NMU (13-23) : 2.81±0.52, and r-NMU (16-23) : 0.88±0.19, respectively. Two heptapeptides, r-NMU (17-23) and r-NMU (16-22), had a relative potency of 0.61 and 0.03 respectively, and elicited maximal contraction at a dose of 10 μM to a similar degree to p-NMU-8. The other shorter C-terminal fragments did not elicit the maximal contraction or any activity. In a rat uterus contraction assay, r-NMU (13-23), but not r-NMU (16-23), at a dose of 4 nM retained as high a stimulatory activity as r-NMU itself. r-NMU (17-22) was the smallest peptide fragment to elicit the maximal sustained contraction at 10 μM. These results indicate that the amino acid sequence Phe-Leu-Phe-Arg-Pro-Arg, corresponding to positions 17 to 22 of r-NMU, may be essential for contractile activity. N-terminal peptide segments Try-Gln-Gly-Pro corresponding to positions 6 to 9, and Ser-Gly-Gly corresponding to positions 13 to 15, appear to be of special importance for potent activity.View full abstractDownload PDF (779K) -
Kazuo KOIKE, Kiyoshi ISHII, Katsuyoshi MITSUNAGA, Taichi OHMOTO1991 Volume 39 Issue 8 Pages 2021-2023
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFive new quassinoids, javanicins U, V, W, X and Y were isolated from Picrasma javanica (Simaroubaceae) collected in Indonesia. Their structures were determined by spectroscopic evidence.View full abstractDownload PDF (585K) -
Shoji YAHARA, Takashi NISHIYORI, Akihide KOHDA, Toshihiro NOHARA, Itsu ...1991 Volume 39 Issue 8 Pages 2024-2036
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA chemical examination of Magnoliae Cortex produced in China (Magnolia officinalis REHD. et WIL S., Magnoliaceae) has led to the isolation of eighteen new lignans and related compounds [four monoterpenyl-lignans : piperitylmagnolol (3), dipiperitylmagnolol (4), piperitylhonokiol (5) and bornylmagnolol (6); seven lignans : magnaldehydes B(8), C(9), magnolignans A(10), B(11), C(12), D(13) and E(14); three norlignans : magnatriol B(16), magnaldehydes D(17) and E(18); and four dilignans : magnolignans F(19), G(20), H(21) and I(22)], together with randainal (7), randaiol (15), sinapic aldehyde, syringaresinol, syringaresinol 4'-O-β-D-glucopyranoside and 6'-O-methylhonokiol. Their structures were determined by the chemical and spectral methods.View full abstractDownload PDF (1914K) -
Yoshinori INOSE, Toshio MIYASE, Akira UENO1991 Volume 39 Issue 8 Pages 2037-2042
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSNine new oleanane-type saponins, solidagosaponins I-IX (1-9), were isolated from Solidago virga-aurea L.(Compositae). Interestingly, these saponins, except 9, have a sugar chain at the 16 position of the aglycone. Moreover, four of them contain a β-hydroxy butyrate group at a portion of the sugar chain. The structures of these compounds were established on the basis of spectroscopic and chemical evidence.View full abstractDownload PDF (756K) -
Hiroshi ISHIKAWA, Sumio KITAHATA, Kazuhiro OHTANI, Osamu TANAKA1991 Volume 39 Issue 8 Pages 2043-2045
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIt was found that a β-fructofuranosidase produced by Microbacterium sp. H-1 has potent trans-β-fructofuranosylation activity from sucrose (donor). By means of this enzyme system, rebaudioside A (RA), the second major sweet steviol glycoside of the leaves of Stevia rebaudiana, was subjected to transfructosylation, affording a mono-β-fructofuranosylated product (RA-F) in a high yield. The structure of RA-F was elucidated as β-D-fructofuranosyl-(2→6)-β-D-glucopyranosyl ester of steviol-13-O-[β-D-glucopyranosyl-(1→2)]-[β-D-glucopyranosyl-(1→3)]-β-D-glucopyranoside. Some improvement in the quality of sweetness was observed for RA-F.View full abstractDownload PDF (558K) -
Mineo SHIMIZU, Takayasu MATSUZAWA, Syoichi SUZUKI, Masao YOSHIZAKI, Na ...1991 Volume 39 Issue 8 Pages 2046-2048
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSQuality evaluation of Angelicae Radix (Touki) was discussed referring to its inhibitory effect on platelet aggregation. No better correlation was observed in quality determined morphologically from the above-ground part of Touki and that determined by anti-platelet aggregation (APA) effects. Phthalides and adenosine, known to be the major components of Touki, were found not sufficient to evaluate the Touki quality as regards APA. Other APA active components have been studied and it was concluded that the APA effect of Touki results from the combined action of plural components. The importance of determining quality based on the action of total extract to meet the purpose for which the substance is to be used was suggested.View full abstractDownload PDF (532K) -
Hideaki OTSUKA, Kayoko YOSHIMURA, Kazuo YAMASAKI, Magdalena C. CANTORI ...1991 Volume 39 Issue 8 Pages 2049-2052
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFrom the aerial parts of Oldenlandia corymbosa, nine iridoid glucoside derivatives were isolated. On spectroscopic investigation, five known compounds were identified, that is, deacetyl asperuloside, asperuloside, asperulosidic acid, deacetyl asperulosidic acid and scandoside methyl ester. The structures of four new compounds were determined to be acylated derivatives of the known compounds, that is, 10-O-benzoyl deacetyl asperulosidic acid methyl ester, and 10-O-benzoyl, 10-O-p-hydroxybenzoyl, and 10-O-p-trans, cis-coumaroyl scandoside methyl esters.View full abstractDownload PDF (706K) -
Akitoshi ASAMI, Yasuaki HIRAI, Junzo SHOJI1991 Volume 39 Issue 8 Pages 2053-2056
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSteroid saponins and flavonoids of the leaves of Phoenix canariensis hort. ex CHABAUD, P. humilis ROYLE var. hanceana BECC., P. dactylifera L., and Licuala spinosa WURMB. have been investigated. Tricin 7-O-β-D-glucopyranoside (1), isorhamnetin 3-O-β-D-glucopyranoside (2), isoquercitrin (3), isorhamnetin 3-O-β-rutinoside (4), rutin (5), and methyl (25S)-proto-Pb (6) from P. canariensis, 1, 6, glucoluteolin (7), tricin 7-O-α-L-rhamnopyranosyl(1→2)-β-D-glucopyranoside (8), and methyl (25S)-proto-loureiroside (9) from P. humilis var. hanceana, 1, 2, 8, methyl proto-prosapogenin A of dioscin (10), methyl proto-reclinatoside (11) and methyl proto-Pb (12) from P. dactylifera, and vitexin (13) and methyl (25S)-proto-dioscin (14) from Licuala spinosa have been isolated and identified.View full abstractDownload PDF (740K) -
Junko IIDA, Masami ONO, Kenichiro INOUE, Tetsuro FUJITA1991 Volume 39 Issue 8 Pages 2057-2062
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThermospray liquid chromatography/mass spectrometry (TSP LC/MS) was applied to the determination of iridoid glycosides. Monosaccharide glycosides exhibited dependence, in terms of sensitivity and mass spectra, on the ion source block temperature. Disaccharide glycosides exhibited dependence in sensitivity and peak shape on the block temperature. The resulting mass spectra gave qualitative information concerning both the aglycon and sugar moieties as well as molecular weights. A methanol extract from the fruit of Gardenia jasminoides was analyzed for iridoid glycosides which were identified by mass spectra and mass chromatograms.View full abstractDownload PDF (767K) -
Takashi KUME, Ryo TAGUCHI, Hiroh IKEZAWA1991 Volume 39 Issue 8 Pages 2063-2067
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe effects of phosphatidylcholine (PC), phosphatidylethanolamine (PE), sphingomyelin (SM), and cholesterol on the activity of phosphatidylinositol-specific phospholipase C(PI-PLC) from Bacillus thuringiensis were studied in detail in phosphatidylinositol (PI)/detergent mixed micelles. By addition of PC, the enzymatic hydrolysis of PI was significantly stimulated in PI/Triton X-100 as well as PI/sodium deoxycholate (SDC) mixed micelles. SM stimulated enzyme activity toward PI/Triton X-100 micelles at a lower molar ratio of SM to PI, but was rather inhibitory at a ratio higher than 2.0. The enzyme activity became significantly lower with an increase of PE or cholesterol in PI/Triton X-100 micelles. Actually, both PE and cholesterol were intensively inhibitory when added at a higher molar ratio to PI in Triton X-100-containing micelles. In the system of PI/SDC mixed micelles, not only PC but also SM, PE and cholesterol enhanced the enzymatic hydrolysis of PI. The difference between PI/Triton X-100 and PI/SDC micelles regarding the effects of these lipids on PI-PLC action, must be dependent on the physical state of micelles formed by these detergents and lipids.View full abstractDownload PDF (756K) -
Masashi TOMODA, Katsutoshi TAKADA, Noriko SHIMIZU, Ryoko GONDA, Naoko ...1991 Volume 39 Issue 8 Pages 2068-2071
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFive kinds of chemically modified products were prepared from Plantago-mucilage A, the representative mucous polysaccharide isolated from the seed of Plantago asiatica L., and their reticuloendothelial system-potentiating and alkaline phosphatase-inducing activities have been investigated. Both activities were markedly enhanced when the mucilage was de-O-acetylated. The products obtained by periodate oxidation, controlled Smith degradation, and partial acid hydrolysis under the two conditions were not effective. Structural features of the partial hydrolyzates were elucidated, and it was shown that these products lost all O-acetyl groups, all xylose branches and many hexuronosyl arabinose side chains.View full abstractDownload PDF (693K) -
Yukio TANAKA, Yutaka TAKAGAKI, Takahiro NISHIMUNE1991 Volume 39 Issue 8 Pages 2072-2076
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSImmediate allergy is caused by a chemical mediator released from basophile and mast cells via cell degranulation due to reaction betweeen an immunoglobulin E (IgE) antibody, bound with the IgE receptor on the cell membrane, and an antigen. The present authors have established a new method for assaying the enzyme activity of β-hexosaminidase as an index of chemical mediator release. Using cultured cells instead of conventional methods based on histamine release from mast cells, the present method permits highly accurate mass screening since it uses a well-established cell line of rat basophilic leukemia cells(RBL-2H3). The effects of metal elements on immediate allergic reaction were evaluated using a newly developed assay system.A total of 38 metal elements were investigated for effects on immediate allergic reactions in vitro. These elements were classified by five types on the basis of action on β-hexosanimidase release : 1) those which showed very strong inhibitory action, such as ZnCl2 and ZrCl4, 2) those which showed relatively strong inhibitory action, such as CdCl2 and CuCl2, 3) those which showed relatively weak inhibitory action, such as CoCl2 and Pb(NO3)2, 4) those which showed neither inhibitory nor promoting action, such as MnCl2 and SrCl2, and 5) AgNO3, which alone showed promoting action.View full abstractDownload PDF (853K) -
Haruki YAMADA, Takayuki NAGAI, Jong-Chol CYONG, Yasuo OTSUKA1991 Volume 39 Issue 8 Pages 2077-2081
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe mode of action of the anti-complementary acidic heteroglycans, AAF-IIb-2 and IIb-3 which consisted of rhamnogalacturonan core and arabinogalactan moieties, purified from the leaves of Artemisia princeps PAMP (Japanese name=Gaiyo) were investigated. The anti-complementary activities of AAF-IIb-2 and IIb-3 were reduced partially in the absence of Ca2+ions. A marked consumption of C4 was observed to have occurred when serum was incubated with both polysaccharides in the presence of Ca2+ ions. AAF-IIb-2 showed more potent C4 consumption than IIb-3. After the incubation of the serum with AAF-IIb-2 in the absence of Ca2+ ions, a cleavage of C3 in the serum was detected by immunoelectrophoresis. AAF-IIb-2 showed more significant consumption of the complement than IIb-3 when rabbit erythrocytes were used in the assay system in the absence of Ca2+ ions. These results indicate that AAF-IIb-2 activates the complement via both the alternative and classical pathways, whereas IIb-3 mainly activates the complement via the classical pathway. The absorption of serum with Protein A-Sepharose results in a decrease of the activity of AAF-IIb-2 and IIB-3. However, the decrease of the activity was restored by the replacement of the immunoglobulin G (IgG) fraction after its recovery from the Protein A-Sepharose. These results suggest that IgG dependent mechanisms are both involved in the anti-complementary activity of AAF-IIb-2 and IIb-3.View full abstractDownload PDF (855K) -
Noriko SHIMIZU, Masashi TOMODA, Makiko SATOH, Ryoko GONDA, Naoko OHARA1991 Volume 39 Issue 8 Pages 2082-2086
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAn acid polysaccharide, named glycyrrhizan GA, was isolated form the stolon of Glycyrrhiza glabra L. var. glandulifera REG.et HERD. It produced a single band on electrophoresis and a single peak on gel chromatography, and its molecular mass was estimated to be 85000. Glycyrrhizan GA is composed of L-arabinose : D-galactose : L-rhamnose : D-galacturonic acid : D-glucuronic acid in the molar ratio of 22 : 10 : 1 : 2 : 1, in addition to small amounts of O-acetyl groups. Part of the hexuronic acid residues exist as methyl esters. Methylation analysis, carbon-13 nuclear magnetic resonance and periodate oxidation studies indicated that its structural features include mainly α-arabino-β-3, 6-galactan type structural units. Glycyrrhizan GA showed remarkable reticuloendothelial system-potentiating activity in a carbon clearance test.View full abstractDownload PDF (724K) -
Eihei FUKUOKA, Midori MAKITA, Yasuo NAKAMURA1991 Volume 39 Issue 8 Pages 2087-2090
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSGlassy pharmaceuticals were prepared by cooling the melts and their state was confirmed by measuring the glass transition temperature (Tg) and the anomalous endothermic peak (heat capacity maximum) in the differential scanning calorimetry (DSC) curves. Glass formation was newly discovered for 24 pharmaceuticals including acetaminophen, chloramphenicol, flufenamic acid and proxyphylline. The value of the ratio Tg and melting temperature (Tm) of these pharmaceuticals lay between 0.69 and 0.85. The rate and quantity of relaxation of glass was determined by the area under the anomalous endothermic peak of the DSC curves of glasses prepared at various cooling rates, that of glassy griseofulvin was found to have the largest among the pharmaceuticals examined. The apparent activation energy of glass transition of chenodeoxycholic acid, griseofulvin and tolnaftate prepared at the cooling rate of -1.25K/min was calculated to be 273.6, 270.3 and 127.6kL/mol, respectively. The influence of heating rate on Tg and the area under the anomalous endothermic peak of the DSC curve of glassy aspirin both immediately and after standing for 60 min at 232K following preparation of the glass was examined. Both factors decreased as heating rate decreased. The apparent activation energy of glass transition of both samples of aspirin was calculated to be 105.6kJ/mol.View full abstractDownload PDF (584K) -
Flavio FORNI, Gilberto COPPI, Maria Angela VANDELLI, Riccardo CAMERONI1991 Volume 39 Issue 8 Pages 2091-2095
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSpray-dried and spray-embedded ethylcellulose microparticles were prepared using a spray-drying technique. The structure of the microparticles (microcapsules or microspheres) changed according to whether the drug (dilitiazem hydrochloride) was dispersed or dissolced in the ethylcellulose solution to be spray-dried. The drug release rate from the microparticles was not affected by the physical state of the drug (amorphous or crystalline state), but by the microparticle structure.View full abstractDownload PDF (984K) -
Kazumichi IMASAKA, Masaru YOSHIDA, Hironobu FUKUZAKI, Masaharu ASANO, ...1991 Volume 39 Issue 8 Pages 2096-2099
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSBiodegradable pasty-type copolyesters with a relatively low molecular weight of 4500 were synthesized by direct copolycondensation of ε-caprolactone (CL) and δ-valerolactone (VL) in the absence of catalysts to evaluate in vivo capabilities of the polymer for implantable controlled release devices in drug delivery systems. The devices in cylindrical shape were prepared by the melt-pressing technique using pasty-type colopy(CL/VL) with 53 mol% CL unit, in which Estracyt and estramustine were used as a water soluble and insoluble drug, respectively. The degradation and drug release in vivo of the devices were examined by subcutaneous implantation in the backs of male rats. The degradation of the device was remarlable accelerated by the presence of hydrophilic Estracyt, and was slightly suppressed by hydrohobic estramustine. The estramustine release profile roughly corresponded to the polymer degradation one. It was found that the degradation of the polymer in the device was affected by hydrophilicity of the drug. A reasonable release of estramustine from the device was kept for a period of more than 20 weeks. Furthermore, the release of the drugs in vivo was able to lead to an atrophy of accessory sex organs such as ventral prostates (VP) and right-side seminal vesicle (SV), reculting in pharmacological influence.View full abstractDownload PDF (1384K) -
Shigeki KOBAYASHI, Akio SAITO, Yoko ISHII, Akira TANAKA, Seisho TOBINA ...1991 Volume 39 Issue 8 Pages 2100-2105
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe molecular orbital (MO) method, as one approach explaining the structure-activity of polychlorinated dibenzo-p-dioxins (PCDDs), was used to understand the relationship between the bioligical activities and electronic state or highest occupied molecular orbital (homo) phase symmetry of PCDDs. The structure-activity relationship of PCDDs could be exolained by the difference between the homo and lowest unoccupied molecular orbital (lumo) energy levels (Δε : difference of εhomo and εlumo) which indicated orbital mixing with other molecules. The magnitude of biological activity was consistent with the following order : 2, 3, 7, 8-tetraCDD>1, 2, 3, 7, 8-pentaCDD>1, 2, 3, 7, 8, 9-hexaCDD>2, 3, 7-triCDD>2, 8-diCDD, with the order of decreasing Δε by Huckel MO calculation. Our method can also estimate a magnitude of biological activity for PCDDs. The structure requirement for high toxicity suggested that the electronic states of PCDDs showed a small value difference (Δε) and S1S2 phase symmetry on the homo for PCDDs. These results indicate that the electron states of PCDDs, which are based on the binding interaction of PCDDs to a cytosolic Ah receptor, play an important role in the appearance of their activity.View full abstractDownload PDF (715K) -
Yasuyuki KITA, Ryuichi OKUNAKA, Takao HONDA, Maiko KONDO, Osamu TAMURA ...1991 Volume 39 Issue 8 Pages 2106-2114
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSHeating of the silylene protected dihydroxystyrene generated from the O-hydroxyacetophenone (3a) at 130-150°C for 15-48h in a sealed tube gave intramolecular [4+2]cycloaddition products (5 and 6). The addition of chloranil to the reaction mixture brought about an oxidative intramolecular [4+2]cycloaddition to give the linearly condensed peri-hydroxy aromatic compound(7a) in excellent yield. The generality of this cycloaddition and application to a short and efficient synthesis of the ABCD ring system of fredericamycin A are described.View full abstractDownload PDF (1421K) -
Nobuo OKABE, Yukiko SAGIMORI, Misa HOKAZE1991 Volume 39 Issue 8 Pages 2115-2116
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe interaction between 3, 4-dihydroxyphenylalanine (DOPA), dopamine, 3-methoxytyramine and homovanillic acid and bovine serum albumin (BSA) was investigated by the ultrafiltration technique. The apparent binding constants were determined assuming the equivalence and independence of the binding sites on the BSA molecule. The binding constants were in the range of log K=2.85 to 3.77 with 1 to 2 binding sites. The affinity of ligands to BSA strengthened with progression of the metabolism in the order of DOPA<dopamine<3-methoxytyramine<homovanillic acid.View full abstractDownload PDF (382K) -
Akio OHSAWA, Takashi ITOH, Kentaro YAMAGUCHI, Chikako KAWABATA1991 Volume 39 Issue 8 Pages 2117-2119
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe N-oxidation products of 4, 5, 6-triaryl-1, 2, 3-triazines were decided to be the 2-oxides on the basis of spectral data and X-ray crystallography; the structures are different from those reported previously.View full abstractDownload PDF (564K) -
Yoshisuke TSUDA, Yuki SAKAI, Katsuko AKIYAMA, Kimiaki ISOBE1991 Volume 39 Issue 8 Pages 2120-2123
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe stereochemistry of hydride reduction of erythrinan-7, 8-diones was markedly affected by the bulkiness of the reagent and the polarity of the solvent : sodium borohydride in ethanol-tetrahydrofuran gave the 7β-hydroxy isomers and tetrabutylammounium borohydride in methanol gave the 7α-hydroxy isomers, stereoselectively. This can be explained in terms of fluctuation of the balance between product development control and approach control. The structures of the products were established by chemical and spectroscopic means. Their O-mesylates were hydrolyzed under basic conditions with epimerization to give a mixture of alcohols with a preference for the 7β-hydroxy derivatives. A similar epimerization of the mesyloxy group was also observed in lithium aluminum hydride reduction.View full abstractDownload PDF (634K) -
Takao YOSHIOKA, Yuichi AIZAWA, Takashi FUJITA, Kan-ichi NAKAMURA, Kuni ...1991 Volume 39 Issue 8 Pages 2124-2125
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe glucoronide of a new oral antidiabetic agent, (±)-5-[4-(6-hydroxy-2, 5, 7, 8-tetramethylchroman-2-yl-methoxy)benzyl]thiazolidine-2, 4-dione (CS-045) (1), was synthesized to confirm the stracture of a metabolite in monkeys (Macacafascicularis) and to examine its antidiabetic activity. The glucuronide also had antidiabetic activity in KK-mice.View full abstractDownload PDF (427K) -
El Houssain BAHAJI, Pierre TRONCHE, Joele COUQUELET, Said HARRAGA, Jac ...1991 Volume 39 Issue 8 Pages 2126-2128
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIn a search for potential immunomodulating agents novel pyrrolo[1, 2-c]pyrimidines were synthesized and their structures elucidated by spectroscopic means. Unfortunately, most of them were cytotoxic and devoid of effects on Tlymphocyte lymphoblastic transformation. Furthermore, they were inactive in the locomotor activity test in mice.View full abstractDownload PDF (528K) -
Atsushi NUMATA, Syoichi KANBARA, Chika TAKAHASHI, Ryoko FUJIKI, Michik ...1991 Volume 39 Issue 8 Pages 2129-2131
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSPartition fractions of hexane, CCl4 and CHCl3 from methanolic extracts of marine algae were each examined for cytotoxic activities against cultured P-388 lymphocytic leukemia cells. Cytotoxic activities were found for partition fractions of 21 species of seaweed. Bioactivity-guided fractionation of the CCl4 partition fraction from Sargassum tortile, exhibiting the most prominent activity, afforded dihydroxysargaquinone (1) and sargatriol (2) previously isolated from this alga. The former was evaluated as a cytotoxic principle, and the latter, showing mederate activity, was suggested to be an artifact derived from 1 during the isolation procedure.View full abstractDownload PDF (518K) -
Shunsuke TOYOKAWA, Tadahiro TAKEDA, Yukio KATO, Katsumi WAKABAYASHI, Y ...1991 Volume 39 Issue 8 Pages 2132-2134
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSKarasurin is an abortifacient plant protein isolated from fresh root tubers of Trichosanthes kirilowii MAXIMOWICZ var. japonicum KITAMURA (Cucurbitaceae). This study describes the presence of protein polymorphism in karasurin (karasurin-A and karasurin-B) separated by ion-exchange chromatography. Two components showed no differences in the molecular weight (ca. 28000), the amino acid composition, the neutral sugar content and part of the amino acid sequence. A unique difference was observed in their isoelectric points (10.1 for karasurin-A and 10.2 for karasurin-B). However, modifications of glycosylation or phosphorylation were not found. Biological assays for inducing mid-term abortion in pregnant mice and inhibition of the growth of BeWo cells gave no significant differences between them. The presence of protein polymorphism in karasurin, whose biological significance is not yet understood, is a first finding among several abortifacient proteins.View full abstractDownload PDF (515K) -
Jen-Der WANG, Takao NARUI, Satoshi TAKATSUKI, Takao HASHIMOTO, Fumiko ...1991 Volume 39 Issue 8 Pages 2135-2137
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSDuring the screening test of the animal crude drug "Chan su" (Chinese name, toad-cake), the venom of Bufo bufo gargorizans CANTOR (Bufonidae), on blood coagulation, platelet aggregation, fibrinolysis system and cytotoxicity, the ethyl acetate extract showed promotive action on platelet aggregation and remarkable cytotoxic activity on HeLa-S3 cells. Nine kinds of bufadienolides were isolated from the ethyl acetate extract by bioactivity-guided fractionation and were identified by chemical and spectral analysis.View full abstractDownload PDF (564K) -
Kaori KUROSAKA, Akira KUCHIKI, Hiroshi NAKAGAWA1991 Volume 39 Issue 8 Pages 2138-2139
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA reversed-phase high-performance liquid chromatographic method was developed for the determination of sulfur in topical pharmaceutical preparations. The mobile phase consisted of methanol-5% acetic acid water (85 : 15). The analysis was carried out using an octadecyl silica column (5 μm, 4.0 mn i.d.×125 mm), with spectrophotometrical detection at 254 nm. Pyrene was used as an internal standard. The calibration curve was linear with a correlation coefficient >0.9996 in the range of 1-3 μg sulfur injected. This method is very useful in determination of sulfur in ointments containing other antibacterial or antiinflammatory drugs.View full abstractDownload PDF (357K) -
Taketsune MIYAHARA, Kusuo NARITA, Yoshio TAKINO1991 Volume 39 Issue 8 Pages 2140-2142
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSStability constants of Cd(II), Cu(II), Hg(II), Pb(II) and Zn(II) chelates with N-(2-naphthyl)ethylenediamine-N, N', N'-triacetic acid (NEDTA) were determined by spectrophotometric and fluorophotometric methods at 25±1°C. The composition of the NEDTA chelate with each metal ion was 1 : 1 both by the molar ratio and the continuous variation methods with spectrophotometry. The stability constants (log K) determined by the spectrophotometric method were as follows : Cd(II), 9.49; Cu(II), 14.62; Hg(II), 15.08; Pb(II), 11.77; and Zn(II), 11.00. Those by the fluorophotometric method were as follows : Cd(II), 9.67; Cu(II), 14.05; Hg(II), 15.93; Pb(II), 11.32 and Zn(II), 10.99.The conditional stability constants (log K') of these metal-NEDTA chelates at pH 4 were in the range of 6 to 11, which were large values compared to usual metal indicators. NEDTA shold be a useful indicator for microchelatometric titration and applicable to detection of a trace amount of several metal ions.View full abstractDownload PDF (500K) -
Kyoko KOIZUMI, Yasuyo OKADA, Emi FUJIMOTO, Yosuke TAKAGI, Hiroshi ISHI ...1991 Volume 39 Issue 8 Pages 2143-2145
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA mixture of maltosylcyclomaltoheptaoses (maltosyl-β-cyclodextrins, G2-βCDs) was prepared from maltose and β-cyclodextrin (βCD) through the reverse action of Klebsiella pneumoniae pullulanase. Three positional isomers of dimaltosyl-βCD in the mixture were separated by high-performance liquid chromatography on a reversed phase column and a graphitized carbon column. Their molecular weights were measured by fast-atom bombardment mass spectrometry, and the structures were established by methylation analysis, hydrolysis with glucoamylase to the known compounds, three positional isomers of diglucosyl-βCD, and 13C-nuclear magnetic resonance spectroscopy.View full abstractDownload PDF (523K) -
Bimane Fluorogenic Substrates for Microdetermination of Angiotensin Converting Enzyme Level in SerumEisuke SATO, Hiromi HATTORI, Satoko NISHIKAWA, Yuichi KANAOKA1991 Volume 39 Issue 8 Pages 2146-2148
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe fluorescence of 9, 10-dioxa-syn-3, 4, 6, 7-tetramethylbimane (bimane) was found to be quenched in the presence of nitrated aromatic amino acid. Bimane peptides containing nitrated amino acid (1a, b) were shown to be useful fluorogenic substrates for the assay of angiotensin I converting enzyme (ACE) from rabbit lung, similar to bimane substrate containing tryptophan (3) previously reported. Among these bimane substrates, substrate 3 was shown to be a potent fluorogenic substrate for microdetermination of the ACE level in human serum.View full abstractDownload PDF (613K) -
Kunio KOBAYASHI, Naomi OGASAHARA, Takafumi SAKOGUCHI, Kaoru TAISHI, Hi ...1991 Volume 39 Issue 8 Pages 2149-2151
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe correlation between the level of fructosamine and glycated proteins, including glycated lipoproteins, in serum from diabetic and nondiabetic subjects was studied. Assay of glycated proteins in serum was performed using an agarose gel film electrophoresis with nitroblue tetrazolium coloration. Glycated albumin correlated well with the fructosamine level in the diabetics (r=0.83-0.92, p<0.01) but showed no correlation with the nondiabetics (r=0.25-0, 26). Also, a high correlation between the glycated β-lipoprotein and fructosamine levels was observed in diabetic patients with hyperglycemia and in nondiabetic subjects with a high risk of atherogenesis (atherogenic index, low-density lipoprotein-cholesterol/high-density lipoprotein-cholesterol >2.8) (r=0.51-0.66, p<0.01). Nondiabetics with a high level of β-lipoprotein, which is well known to cause high atherogenesity, showed a high level of glycated β-lipoprotein similar to that in the diabetic groups with hyperglycemia; therefore, the high level of glycated β-lipoprotein seems to be attributable not only to the hyperglycemia-accelerated glycation of β-lipoprotein but also to an increase in the level of β-lipoprotein in serum.Consequently, the present results show that the fructosamine level in serum reflects not only the glycation of albumin but also that of lipoproteins which are known to increase in diabetes mellitus.View full abstractDownload PDF (527K) -
Hiroshi OGAWARA, Kyoichiro HIGASHI, Keijiro UCHINO, Nigel B. PERRY1991 Volume 39 Issue 8 Pages 2152-2154
Published: August 25, 1991
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSMycalamide A and mycalamide B, isolated as antiviral and antitumor agents from a New Zealand sponge of the genus Mycale, converted the morphology of ras-transformed NRK-cells to normal morphology at 10 and 1 ng/ml, respectively. The effect on protein synthesis suggests that these agents converted the morphology by preferentially inhibiting the biosynthesis of p21 protein.View full abstractDownload PDF (1425K)