All issues
Volume 31, Issue 2
Displaying 1-50 of 64 articles from this issue
-
TANEKAZU KUBOTA, BUNJI UNO, YOSHIO MATSUHISA, HIROSHI MIYAZAKI, KENJI ...1983 Volume 31 Issue 2 Pages 373-385
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIn order to confirm and to extend the scope of the equation (Eoxd1/2-Ered1/2)=k11, 3 EUVho-lu+k2, presented previously by us, the polarographic half-wave reduction (Ered1/2) and oxidation (Eoxd1/2) potentials in nonaqueous media and the electronic spectra of 4, 4'-disubstituted stilbenes have been measured and analyzed by means of the equation with reasonable results. The substituent effect on Eoxd1/2 and Ered1/2 values has been well described by using the Hammett-type substituent constants. This result has been combined with the above equation, and thus a general equation describing the substituent effect on electronic spectra in terms of substituent constants has been derived as EUVho-lu=aF+bR+c, F and R being Swain and Lupton's substituent constants. This equation has been experimentally examined using the strong longest-wavelength π-π* bands of 4, 4'-disubstituted stibenes and azoxybenzenes. The results were quite reasonable. Finally, the description of the substituent effect on electronic spectra in terms of substituent constants is discussed on the basis of molecular orbital theory.View full abstractDownload PDF (1112K) -
MASAHIRO MIYASHITA, YOSHIYUKI SEYAMA, KIYOKO KAJI, SABURO YAMASHITA1983 Volume 31 Issue 2 Pages 386-393
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIn order to obtain highly purified monoiodohistidine (MIH) in high yield, the optimum iodinating conditions for histidine were examined by HPLC. The isolation and purificaton of MIH from the reaction mixture were attempted by liquid chromatography (LC). The yields of iodohistidines [MIH and diiodohistidine (DIH)] were found to be dependent on the amount and type of the iodinating reagents ; that is, the molar ratio of histidine to iodinating reagent (I2) should be exactly 1 : 1 for MIH and 1 : 2 for DIH for the maximum yield. Purification of MIH was successfully carried out by LC on Dowex 50 (0.05 M 2, 6-lutidine), SEP-PAK C18 cartridge (Waters Associates), and Sephadex G-10 (0.1N AcOH). The overall yield of MIH·HCl obtained by the present method was 57%, which is the highest so far reported.View full abstractDownload PDF (764K) -
YUTAKA HIRANO, TADASHI EGUCHI, MASAJI ISHIGURO, NOBUO IKEKAWA1983 Volume 31 Issue 2 Pages 394-400
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS(23R)- and (23S)-23-Hydroxy- and 23, 25-dihydroxycholesterols were synthesized via 3β-tetrahydropyranyloxycholesta-5, 25-dien-23-ol (5) from cholenic acid acetate (1). The stereochemistry at the C-23 position of related steroids is also discussed.View full abstractDownload PDF (791K) -
KENJI YAMAGATA, YUKIHIKO TOMIOKA, MOTOYOSHI YAMAZAKI, KANJI NODA1983 Volume 31 Issue 2 Pages 401-406
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe reaction of 2-benzamido-3-cyano-4, 5-dihydrothiophene (I) with cyclohexylamine gave 4-cyclohexylamino-2-phenyl-5, 6-dihydrothieno [2, 3-d] pyrimidine (IVa) in 93% yield. Similarly, I reacted with morpholine, piperidine and pyrrolidine to yield the corresponding 4-amino-2-phenyl-5, 6-dihydrothieno [2, 3-d] pyrimidines (IVb-d). In a similar manner, 2-benzamido-3-cyano-5-methyl (or 4-phenyl)-4, 5-dihydrothiophene (II or III) reacted with amines to form the 4-amino derivatives (Va-d or VIa-d) corresponding to IVa-d. On the other hand, I, II and III were converted on treatment with dimethylamine hydrochloride in pyridine to the corresponding 2-phenyl-5, 6-dihydrothieno [2, 3-d] pyrimidin-4 (3H)-ones (VII-IX). Compounds IVa-d, Va-d and VIa-d were also synthesized from 4-chloro-2-phenyl-5, 6-dihydrothieno [2, 3-d] pyrimidines and appropriate amines.View full abstractDownload PDF (579K) -
MASAAKI SHIBUYA, YUTAKA EBIZUKA, HIROSHI NOGUCHI, YOICHI IITAKA, USHIO ...1983 Volume 31 Issue 2 Pages 407-413
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIn order to clarify the structure-activity relationship of 4-O-methylcryptochlorophaeic acid (1), which is a lichen meta-depside and a potent inhibitor of prostaglandin (PG) biosynthesis found in our previous screening work, arylcarboxylic acids (5-8) corresponding to the monomeric moieties of 4-O-methylcryptochlorophaeic acid (1) were synthesized and tested for inhibitory effect against PG biosynthesis by an enzyme system prepared from rabbit renal medulla. They were a hundred times less active than 4-O-methylcryptochlorophaeic acid (1), indicating that the dimeric structure of the meta-depside is essential for inhibitory activity against PG biosynthesis. Kinetic studies on the mechanism of inhibition revealed that 4-O-methylcryptochlorophaeic acid (1) inhibits PG biosynthesis competitively with respect to the substrate, arachidonic acid. The three dimensional structure of 4-O-methylcryptochlorophaeic acid (1), which is expected to have a molecular structure able to fit into an active site that accommodates arachidonic acid, was determined by single crystal X-ray analysis with the direct approach. The obtained structure reveals that 4-O-methylcryptochlorophaeic acid (1) maintains a rigid conformation by forming a strong hydrogen bond between a hydroxy group and a methoxy group. Based on these findings, a new active site model of fatty acid cyclooxygenase is proposed in order to explain the inhibition by the meta-depside and acidic non-steroidal antiinflammatory drugs.View full abstractDownload PDF (770K) -
KEISHIRO NAGAO, MASATO CHIBA, SANGWON KIM1983 Volume 31 Issue 2 Pages 414-422
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA total synthesis of (±)-carpesiolin (3) is reported starting from the hydroazulenone (2), which is a key intermediate of helenanolide synthesis. For the introduction of the C6 to C8 functionalities, 2 was converted to the epoxy-alcohol (5). Its structure was confirmed by chemical and spectroscopic evidence. After construction of the γ-lactone ring, the tert-butyl protective group was removed from the ester (15) by acid-catalyzed thermolysis. However, this reaction was unexpectedly accompanied by concomitant 1, 3-acyl migration with inversion of the configuration at C4 to yield the hydroxy-ester (16), whose structure was established by analysis of its proton magnetic resonance spectrum and some chemical reactions. After manipulation of the protective group to give the tetrahydropyranyl ether (18), its conversion to (±)-carpesiolin was achieved by (i) introduction of the exo-methylene group onto the lactone ring, (ii) oxidation to the cyclopentanone (24), and (iii) deprotection of the C6 hydroxyl group.View full abstractDownload PDF (1105K) -
YASUOKI MURAKAMI, YUUSAKU YOKOYAMA, CHIYOKO SASAKURA, MAKIKO TAMAGAWA1983 Volume 31 Issue 2 Pages 423-428
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS1, 1-Disubstituted hydrazines were prepared from the corresponding 1, 1-disubstituted ureas by means of the Hofmann rearrangement reaction. The yields were fairly good, except from the ureas susceptible to oxidation, and thus the present method represents an additional and efficient procedure for the synthesis of 1, 1-disubstituted hydrazines.View full abstractDownload PDF (707K) -
MASAO WADA, HIDEO NAKAI, YASUHIKO SATO, YASUMARU HATANAKA, YUICHI KANA ...1983 Volume 31 Issue 2 Pages 429-435
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSBased on the regioselective remote photocyclization of a pair system consisting of a phthalimide group and a methylthio group, a homologous series of N-substituted phthalimides (4) possessing a terminal sulfide function in the poly-ether side chain afforded, on irradiation, seven- to fifteen-membered crown ether analogs (5-7) in moderate yields.View full abstractDownload PDF (785K) -
ATSUSHI NUMATA, KAZUKO HOKIMOTO, TSURUKO TAKEMURA, SHUNYO MATSUNAGA, R ...1983 Volume 31 Issue 2 Pages 436-442
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS(+)-Juvabione (I) and two new analogs (III and IV) were isolated, together with trans-4-hydroxycinnamic acid (XIII) and vanillin (XIV), from the wood of Abies sachalinensis MAST. (Pinaceae). The structures of III and IV were established to be cis-4-[3 (S)-hydroxy-l (R), 5-dimethylhexyl] cyclohexane-l-carboxylic acid and trans-4-[3 (S)-hydroxy-l (R), 5-dimethylhexyl] cyclohexane-l-carboxylic acid, respectively, on the basis of chemical and spectral evidence.View full abstractDownload PDF (779K) -
YASUO OHTSUKA, TAKESHI OISHI1983 Volume 31 Issue 2 Pages 443-453
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIntramoleclar acylation of the sulfur-stabilized carbanions of the acyclic ester 9 and amide sulfides 11 was carried out as a model study for developing an effective method for the construction of medium-ring ketones by ring closure. Reaction of 9a-c or 11a-g with lithium diisopropylamide (LDA) proceeded smoothly and the expected keto sulfides 10a-c or 12a-g, respectively, were obtained. In the cases where R1 and/or R2 in 11 were normal alkyl groups, the reaction did not take place. However, these difficulties were readily overcome either by introducing a methyl group next to the carbonyl group or by converting the sulfides into the corresponding sulfoxides or sulfones. Acylation in the allyl sulfides 11b, d, f and the allyl sulfone 20b takes place at the α-position to the sulfur atom, yielding β, γ-unsaturated ketones. A reductive removal of the sulfide moiety or its conversion into other functional groups was also examined.View full abstractDownload PDF (1130K) -
YASUO OHTSUKA, TAKESHI OISHI1983 Volume 31 Issue 2 Pages 454-465
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAn effective general method for the construction of medium-ring ketones from the corresponding ω-bromocarboxylic acids is described. When the diamide disulfide 10 was treated with NaBH4 and NaH in 2-propanol, reductive cleavage of the sulfur-sulfur bond and concomitant intramolecular coupling of the resulting thiolate anion with the terminal bromide took place and the large-ring lactam sulfide 7, which was the key intermediate for the synthesis of medium-ring ketones, was obtained. Although lithium diisopropyl amide (LDA) treatment of 11 followed by reductive desulfurization provided cycloundecanone (13d) in only 19.5 % yield, intramolecular cyclization of the α-methylated analogues 17 with LDA proceeded smoothly and the keto sulfoxides 18 were obtained in quantitative yields. In the case of the lactam sulfones 21, tert-BuOK was effective as a base for the intramolecular cyclization, affording the keto sulfones 22 in quantitative yields. The keto sulfoxides 18 and sulfones 22 were subjected to reductive desulfurization with Al-Hg to yield medium-ring ketones 19 and 13, respectively, in high yields.View full abstractDownload PDF (1104K) -
MINEO FUKUI, TOSHIYA IKEDA, TAKESHI OISHI1983 Volume 31 Issue 2 Pages 466-475
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSBase-promoted proton abstraction from π-(N-tert-butyldimethylsilyl-N-methylaniline) chromium tricarbonyl (3) took place predominantly at the meta position and variously meta-substituted N-methylacetanilides 4 were obtained after reactions with electrophiles followed by oxidative decomplexation and N-acetylation. Application of the present method to variously N, N-disubstituted anilines 5 and phenols 7 was then examined and the corresponding meta substituted anilines 6 and phenol 9 were obtained.View full abstractDownload PDF (1064K) -
KATSUHIDE MATOBA, YUKIKO MIYATA, TAKAO YAMAZAKI1983 Volume 31 Issue 2 Pages 476-481
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS1-Cinnamoylisoquinoline (I) was treated with perchloric acid in ethanol to give 2, 5-dihydro-1-oxo-3-phenyl-[1H] pyrrolo [2, 1-α] isoquinolinium perchlorate (V) in the yield of 48.1%. V was derived to 1-(4-nitrobenzoyloxy)-3-phenyl-[1H] pyrrolo [2, 1-α] isoquinoline (VI) by means of the Shotten-Baumann reaction. 3-Methylquinoxalin-2-yl 4-phenyl-1, 3-butadienyl ketone (VIIa) was treated with acid to give 3-hydroxy-4-methyl-1-styrylpyrrolo [1, 2-α] quinoxalinium perchlorate (VIIIa) in quantitative yield. VIIIa was treated with diazomethane to give 3-methoxy-4, 5-dimethyl-1-styrylpyrrolo [1, 2-α] quinoxalinium perchlorate (XI). VIIIa gave a monobromide (XIIa) on treatment with bromine in carbon tetrachloride. The rate of acid-catalyzed cyclization of 3-methylquinoxalin-2-yl 4-(4-nitrophenyl)-1, 3-butadienyl ketone (VIIb) was slower than that of VIIa. Attempts to cyclize XIV intramolecularly to 2, 5-dihydro-1-phenylpyrrolizin-3 [1H]-one (XVI) were unsuccessful under various conditions.View full abstractDownload PDF (695K) -
ISAO MINAMI, HIROSHI AKIMOTO, MASAHIRO KONDO, HIROAKI NOMURA1983 Volume 31 Issue 2 Pages 482-489
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSNovel 2-(2-aminothiazol-4-yl)-2-sulfoacetyl cephalosporins (10a-c) were synthesized by two routes : A, acylation of 7-aminocephalosporanic acid (8a) or its analogs (8b, c) with an active derivative of 2-(2-aminothiazol-4-yl)-2-sulfoacetic acid, and B, side chain sulfonation of γ-chloroacetoacetyl cephalosporins (13a, b) with SO3-dioxane and subsequent thiazole ring formation by treatment with thiourea. The cephalosporin with 4-carbamoylpyridiniomethyl at the 3-position (10c) showed a potent antipseudomonal activity but had poor activity against other gram-negative bacteria, while the cephalosporin with 1-methyltetrazol-5-ylthiomethyl at the 3-position (10b) showed a broad spectrum but caused no inhibition of Pseudomonas aeruginosa.View full abstractDownload PDF (840K) -
SETSUKO SEKITA, KUNITOSHI YOSHIHIRA, SHINSAKU NATORI1983 Volume 31 Issue 2 Pages 490-498
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAssignments of the 13C-nuclear magnetic resonance signals of eight naturally occurring chaetoglobosins were established. Incorporations of [1-13C]-, [2-13C]-, and [1, 2-13C2]-acetate, [13C-methyl]-L-methionine, and [1-13C]-and [2-13C]-DL-tryptophan into chaetoglobosins A and C by Chaetomium globosum demonstrated that the molecules were formed from nine units of acetate/malonate, three C1 units, and one unit of tryptophan.View full abstractDownload PDF (730K) -
NORIKO SHIMIZU, MASASHI TOMODA1983 Volume 31 Issue 2 Pages 499-506
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe major acidic polysaccharide, named Zizyphus-pectin A, was isolated from the fruits of Zizyphus jujuba MILLER var. inermis REHD. The final preparation was homogeneous as determined by ultracentrifugal analysis, cellulose acetate and glass-fiber electrophoresis, and gel chromatography. It was composed of D-galacturonic acid, L-rhamnose, D-galactose, and L-arabinose in the molar ratio of 35 : 1 : 1 : 4, and its molecular weight was estimated to be 263000. The major part (58%) of D-galacturonic acid exists as the methyl ester. O-Acetyl groups were identified and the content amounted to 2.3%. Partial acid hydrolysis gave 2-O-(α-D-galactopyranosyluronic acid)-L-rhamnose, and di- to penta- saccharides consisting of α-1→4-linked D-galactopyranosyluronic acid units. In addition, reduction of carboxyl groups followed by methylation analysis showed that the pectin possesses a backbone chain consisting of α-1→4-linked D-galactopyranosyluronic acid residues which are interspersed with α-1→2-linked L-rhamnopyranose residues having side chains at position 4. The pectin has β-1→4-linked D-galactopyranosyl linear side chains and α-1→5-linked L-arabinofuranosyl highly branched side chains having 1→3-linked branching points.View full abstractDownload PDF (931K) -
TADASHI OKAWARA, KENTARO NAKAYAMA, MITSURU FURUKAWA1983 Volume 31 Issue 2 Pages 507-512
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe reaction of 1, 3-disubstituted thioureas (1) with β-haloacyl halides (2) was carried out in 5% NaOH-CH2Cl2 to afford 1, 3-disubstituted 2, 3, 5, 6-tetrahydro-2-thioxopyrimidin-4 (1H)-ones (3) or 2-N, 3-disubstituted 2, 3, 5, 6-tetrahydro-2-imino-1, 3-thiazin-4-ones (4) in yields of 51-63 or 54-68%, respectively.View full abstractDownload PDF (609K) -
EIKO OHTSUKA, JITSUHIRO MATSUGI, HIDEAKI TAKASHIMA, SHOICHI AOKI, TOSH ...1983 Volume 31 Issue 2 Pages 513-520
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESStRNA fragments containing modified nucleosides have been synthesized either by condensation of nucleotides containing a modified base or by modification of oligonucleotides. Ribothymidine 3'-phosphate was prepared by condensation of the silylated base with protected D-ribose followed by phosphorylation. Ribothymidine-containing trimer, T-Ψ-C, was synthesized by the phosphodiester method. A ribothymidine-containing hexamer T-U-C-A-A-A and a 2'-O-methylcytidine containing hexamer C-G-G-G-Cm-Up were synthesized by the phosphotriester method. A dihydrouridine-containing trimer D-A-G and a 7-methylguanosine-containing trimer m7G-U-C were obtained by modification of the trimers by reduction and methylation, respectively.View full abstractDownload PDF (1050K) -
MASATOSHI YAMATO, KUNIKO HASHIGAKI, KIWAMU HIRAMATSU, KENJI TASAKA1983 Volume 31 Issue 2 Pages 521-526
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSeveral 1-alkyl-4-piperidylidene analogs were synthesized and tested for inhibitory activity on the compound 48/80-induced release of histamine from mast cells. 4-(4-Isochromanylidene) (12b) and 4-(diphenylmethylene) (14) derivatives of 1-benzylpiperidine were much more active than the lead compounds, 1-benzylspiro [isochroman-piperidines] (1b and 2b).View full abstractDownload PDF (650K) -
MASAO HATTORI, KAZUHARU IENAGA, WOLFGANG PFLEIDERER1983 Volume 31 Issue 2 Pages 527-537
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSContrary to earlier reports on the interaction between polyadenylic acid (poly (A)) and poly-5-bromouridylic acid (poly (br5U)), poly (A) was demonstrated to form both 1 : 1 and 1 : 2 complexes with poly (br5U) in 0.1 MNa+, pH 7.3, at 25°C by reconstructing mixing curves. Under comparable conditions, newly synthesized poly-2-methyladenylic acid (poly (m2A)) and poly-2-ethyladenylic acid (poly (e2A) formed only 1 : 1 complexes with poly (br5U), possibly having non Watson-Crick base pairing due to steric hindrance between the C (2)-alkyl substituents of adenine and the C (2)-carbonyl oxygen of bromouracil in polynucleotides, whereas poly-2-isopropyladenylic acid (poly (iso-pr2A)) did not interact with poly (br5U). On the other hand, with polyinosinic acid (poly (I)), poly (m2A) formed a 1 : 2 complex with hydrogen bonding at both N (1) and N (7) of 2-methyladenine, similar to the structure of poly (A)·2poly (I), whereas poly (e2A) formed only a 1 : 1 complex, possibly having non Watson-Crick type base pairing due to steric hindrance of a bulkier substituent which blocks pairing at the N (1) bonding site of 2-ethyladenine to hypoxanthine, and poly (iso-pr2A) again gave no complex at all. The ultraviolet (UV) and circular dichroism (CD) spectra and thermal stabilities of these duplexes and triplexes were compared under various conditions.View full abstractDownload PDF (958K) -
NOBUYA KATAGIRI, YUTAKA MIURA, RYUJI NIWA, TETSUZO KATO1983 Volume 31 Issue 2 Pages 538-544
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe reaction of ketene with Schiff bases was investigated. Heating of ketene with Schiff bases (1a-l) without solvent gave α-unsubstituted β-lactams (2a-l). The reaction of ketene with ethyl N-furfurylideneglycinate (1k) to give the β-lactam 2k was carried out at various temperatures, and it was found that the yield of 2k was not much influenced by the reaction temperature. β-Lactams (2d, f, k, l) were treated with 10% aqueous sodium hydroxide in dioxane to give the corresponding carboxylic acids (4d, f, k, l) in good yields. Compounds 4d, f, l reacted with various amines in the presence of dicyclohexylcarbodiimide (DCC) to give the corresponding amides (5a-c, 8a-d).View full abstractDownload PDF (612K) -
MANABU NODE, KIYOHARU NISHIDE, KEIICHIRO OHTA, KAORU FUJI, EIICHI FUJI ...1983 Volume 31 Issue 2 Pages 545-551
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSOn treatment with a metal halide and alkanethiol system, polycyclic aromatics having various substituents such as hydroxy, alkoxy, phenoxy, acetoxy, and halogen were easily converted into alkylthiopolycyclic aromatics in high yields. The chemo and regioselectivity are described for the reaction of disubstituted naphthalenes.View full abstractDownload PDF (696K) -
HIROYUKI KIKUCHI, YASUMASA TSUKITANI, IWAO SHIMIZU, MOTOMASA KOBAYASHI ...1983 Volume 31 Issue 2 Pages 552-556
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSOn the basis of chemical and physicochemical evidence, the chemical structure of foliaspongin, an antiinflammatory active principle of the Okinawan marine sponge Phyllospongia foliascens (PALLAS), was elucidated as a new scalarane-type bishomosesterterpene (3).View full abstractDownload PDF (598K) -
NOBUYUKI HAMANAKA, MASAAKI TODA, SHIGERU TAKAOKA, MASAKI HAYASHI, TAKA ...1983 Volume 31 Issue 2 Pages 557-559
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSProstaglandin Bx (PGBx), a complex mixture of closely related oligomers of Prostaglandin B1 (PGB1) or 15-dehydro-PGB1 which has unique biological activities, is formed under basic conditions. For mechanistic studies of the oligomerization, two dimers of 15-dehydro-PGB1 were prepared under mild conditions and their structures were determined by means of nuclear magnetic resonance (NMR) spectroscopic studies.View full abstractDownload PDF (411K) -
TAKASHI SOHDA, KATSUTOSHI MIZUNO, TAKEO HIRATA, YOSHITAKA MAKI, YUTAKA ...1983 Volume 31 Issue 2 Pages 560-569
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS5-Benzylthiazolidine-2, 4-dione derivatives were prepared and examined for antisecretory and antiulcer activities using pylorus-ligated rats and water-immersion stress rats. Some of these compounds, in particular, 5-(2, 4, 5-tripropoxybenzyl) thiazolidine-2, 4-dione (4) and 5-(2, 4-dimethoxybenzyl) thiazolidine-2, 4-dione (23), exhibited pronounced pharmacological activities. Structure-activity relationships are discussed.View full abstractDownload PDF (954K) -
KIMIAKI HAYASHI, YASUHIKO OZAKI, KENICHI NUNAMI, TOMOFUMI UCHIDA, JYOJ ...1983 Volume 31 Issue 2 Pages 570-576
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS(3S)-2-[(2S)-3-Mercapto-2-methylpropionyl]-1, 2, 3, 4-tetrahydroisoquinoline-3-carboxylic acid [(3S), (2S)-6a] was prepared by the reaction of (3S)-1, 2, 3, 4-tetrahydroisoquinoline-3-carboxylic acid tert-butyl ester [(3S)-2a] or benzyl ester [(3S)-2b] with 3-benzoylthio-2-methylpropionyl chloride (3a), followed by fractional crystallization and removal of the protective group. The absolute configuration of (3S), (2S)-6a was confirmed by X-ray diffraction analysis of the thiazepino [4, 3-b] isoquinoline compound (7) derived from 6a. Resolution of 3-benzoylthio-2-methylpropionic acid (8) was completed by using optically active phenylalanine amide as a resolving agent. The other optical isomers of (3S), (2S)-6a were prepared by the reaction of (3S)- or (3R)-2b with optically active 3a. The in vitro ACE inhibitory activity of each isomer of 6a was evaluated. Among them, (3S), (2S)-6a was found to be the most potent inhibitor with an IC50 value of 8.6×10-9M. Compound (3S), (2S)-6a induced a dose-dependent inhibition of the pressor response to angiotensin I after oral administration to normotensive anesthetized rats. Moreover, (3S), (2S)-6a markedly reduced the systolic blood pressure in renal hypertensive rats (RHR) and spontaneously hypertensive rats (SHR). The in vivo ACE inhibitory activity and the hypotensive effects of (3S), (2S)-6a were comparable to those of captopril.View full abstractDownload PDF (800K) -
MINEO SHIMIZU, TOSHIMITSU HAYASHI, NAOKATA MORITA, FUMIYUKI KIUCHI, HI ...1983 Volume 31 Issue 2 Pages 577-583
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA biologically active monoterpene, paeoniflorigenone (2), was isolated from the roots of Paeonia albiflora PALLAS. The structure of 2 was elucidated by means of chemical and spectral studies and its absolute structure was determined by X-ray analysis, by the direct method.View full abstractDownload PDF (726K) -
KEIKO YAMAGUCHI, TSUTOMU OIKAWA, HARUO NOGAMI, CHIAKI MORIWAKI1983 Volume 31 Issue 2 Pages 584-590
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIt was demonstrated by electronmicroscopy and by the determination of enzymic activity in the mesenteric perfusate that horseradish peroxidase (HRP) was absorbed from adult rat intestine. When 1200 units of HRP was infused into the intestinal lumen of normal rats, 2.8 units of the enzyme was recovered in the mesenteric perfusate collected for 90 min. On the other hand, the absorption of HRP decreased specifically in rats immunized with HRP. In an in vitro experiment using everted gut sac, the effect of intraperitoneal immunization (three times) on HRP influx was 2-to 3-fold greater than that of subcutaneous immunization (six times). Although the influx was unchanged in the rats injected subcutaneously three times, the recovery of HRP in the perfusate after the same sensitization decreased significantly compared with the control rats. These results suggest that the absorption of antigen decreases after active sensitization and that the effect of immunization on the intestinal absorption depends on the administration route of antigen.View full abstractDownload PDF (1611K) -
KIYOMI KIKUGAWA, TOMIYA SASAHARA, TSUTAO KURECHI1983 Volume 31 Issue 2 Pages 591-599
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSesamol dimer (I) was converted into the quinone (II) having an absorption maximum at 550 nm by treatment with hydrogen peroxide, linoleic acid hydroperoxide or tert-butyl hydroperoxide in the presence of hemoglobin. The order of the color-forming activity was linoleic acid hydroperoxide»hydrogen peroxide>tert-butyl hydroperoxide. Methemoglobin was much more effecive than oxyhemoglobin for coloration. Hydrogen peroxide and methemoglobin produced a complex which generated singlet oxygen and hydroxyl radical, the latter being effective for coloration of I. The reaction of linoleic acid hydroperoxide with methemoglobin produced a complex which generated peroxy free radical and then the keto acid and singlet oxygen ; the peroxy free radical was found to be the active species for oxidation of I. Sesamol dimer (I) may be useful for chromogenic assay of hydroxyl and peroxy free radicals.View full abstractDownload PDF (878K) -
SACHIKO TAKEBE, KYOICHI KOBASHI, JUNICHI HASE, TAMOTSU KOIZUMI1983 Volume 31 Issue 2 Pages 600-604
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAfter the oral and intraperitoneal administration of urea-14C and sodium bicarbonate-14C to rats, the radioactivity of carbon dioxide expired in breathing air and that of urea transported into the blood were measured. Ureolysis was examined quantitatively on the basis of a compartment model analysis, where the hydrolysis and transport of substances were assumed to be first-order processes. Ureolysis in vivo was found not only in the lumen, but also in other tissues such as juxtamucosa, kidney and liver ; the former rate constant (h-1) was 0.759 (k) and the latter 0.0122 (k'). The constant k observed in normally fed rats was 9.5-fold higher than k in fasted rats, but k' was low in both cases. The administration of nicotino-hydroxamic acid as a urease inhibitor completely depressed k, but k' was not affected. On the bases of 71.0 mg·kg-1·h-1 of urea excreted in urine and the rate constants obtained for transport and hydrolysis of urea, the amounts of urea hydrolyzed in the lumen and other tissues were estimated to be 4.92 and 5.04 mg·kg-1·h-1, respectively. Consequently, it was calculated that urea hydrolyzed in the body corresponded to 12.3% of urea synthesized in the liver.View full abstractDownload PDF (553K) -
MIDORI MIHARA, MITSURU UCHIYAMA1983 Volume 31 Issue 2 Pages 605-611
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIn order to classify the 2-thiobarbituric acid (TBA)-reactive materials in various tissues, control and CCl4-intoxicated rat liver homogenates as well as methyl linoleate hydroperoxide (MLHPO) and malonaldehyde were subjected to the TBA reaction under both aerobic and anaerobic conditions. The TBA reaction of malonaldehyde proceeded regardless of the absence of oxygen, while the TBA value obtained from MLHPO catalyzed by tissue under anaerobic conditions was as low as 15% of the aerobic value, and tissue homogenate, even prepared from CCl4-intoxicated rat liver, gave practically no color development under anaerobic conditions. However, after an aerobic preincubation, MLHPO and tissue homogenate produced TBA-reactive materials which could react with TBA even under anaerobic conditions. These TBA-reactive materials are not malonaldehyde itself but seem to be some further-oxidized and more polar lipid hydroperoxide. The addition of Fe to the TBA reaction medium seems to negate the requirement for oxygen. The magnitude of the TBA value obtained anaerobically from tissue with Fe addition was similar to the TBA value obtained aerobically from tissue without Fe addition.View full abstractDownload PDF (723K) -
SHIGERU AONUMA, YASUHIRO KOHAMA, TOSHITAKE MAKINO, IKUFUMI YOSHITAKE, ...1983 Volume 31 Issue 2 Pages 612-619
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe distribution of [1-14C] acetamidino-antiarrhythmic peptide (14C-AAP) in mice was studied by direct counting and whole-body autoradiography. Intravenously injected 14C decreased rapidly in blood during 1 to 20 min and gradually during 20 to 180 min. At 180 min 68% of the radioactivity had appeared in the urine. At 60 min unmetabolized 14C-AAP was present in the urine. At 1 min the radioactivity was highest in the kidney, followed by the lung, liver, and myocardium in that order. Radioactivity increased in the kidney and myocardium during 1 to 6 min, while the radioactivity in the lung and liver decreased rapidly from 1 to 60 min. Autoradiograms revealed that at 6 min after injection (i.v.) the highest radioactivities were seen in the kidney, urine, heart, lung, submaxillary gland, bone and gut wall. No radioactivity was present in the brain, spinal cord, gut contents or fetus. At 20 to 60 min the radioactivity levels in the organs were much less than those seen at 6 min, except for the kidney and urine. In mice orally given 14C-AAP, the maximum plateau levels of radioactivity were found in the myocardium (0.04% of dose) and blood (2.5%) at 40 to 120 min. In serum at 60 min, 14C-AAP was still present in the original molecular form, unbound to macromolecules. Thus, 14C-AAP accumulates in the myocardium of the target organ for a short time immediately after injection (i.v.), corresponding to the period of the QTc interval prolongation by AAP. 14C-AAP does not accumulate for long in any organ except for the kidney, and is largely excreted in urine within 60 min.View full abstractDownload PDF (857K) -
MASAKI HASEGAWA, HIDEO SATO, YUKIO SUMITA, AKINOBU OTSUKA1983 Volume 31 Issue 2 Pages 620-625
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIn order to evaluate the resistance of an oblong tablet with a center groove to breaking into halves, various tests for measuring the tablet breaking load were performed. The results were compared with those of a shock test which was considered to simulate the impacts occurring in the processes of packaging, handling and transport. It was found that the hardness values obtained from the Monsanto hardness tester were independent of the shock test data. This may be due to the difference in mechanism of tablet fracture between the two tests. In the bending test, all the test tablets cleanly fractured into halves. However, the values of breaking load obtained from a Kiya hardness tester were, on the whole, too small to be useful for distinguishing between tablets having different strengths. Since this result seemed to be caused by the high loading rate in this test, the influence of the loading rate was examined by the use of a material testing machine. When the rate of loading was sufficiently slow, higher breaking load values were obtained and differences in mechanical strength between the different tablets were easily detected. The flexure breaking loads obtained from the tester with a spring balance were in good agreement with the corresponding shock test data. In this test, the actual loading rate may be reduced by the buffer action of the spring, resulting in both higher breaking load values and greater apparent differences in strength between the test tablets. It is thought that this instrument is suitable as a conventional device for evaluating the fracture resistance of this type of tablet.View full abstractDownload PDF (610K) -
HSINGCHU HSU, JUN WATANABE1983 Volume 31 Issue 2 Pages 626-631
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAn in vivo study on the elimination of rabbit muscle creatine phosphokinase (CPK) following intravenous administration has been carried out with nine rabbits selected for low endogeneous CPK fluctuation character. A two-compartment open model is proposed for the disposition of CPK. The equation Cp=Ae-α1+Be-β1 was employed to fit the profile of CPK activity in the plasma. The pharmacokinetic parameters of CPK in rabbits were determined at low, medium and high dose levels, and the factors which affect the estimation of pharmacokinetic parameters are discussed. The elimination of CPK appeared to be independent of the injected dose, but the intersubject variability was significant. The pharmacokinetic parameters α and β at high injected dose (860 U/kg body weight, n=9) were estimated to be 0.432±0.274 h-1 and 0.099±0.031 h-1. This value for β in vivo is significantly larger than the inactivation rate constant of CPK in vitro. Hence, there must be some other mechanism involved in vivo in addition to simple inactivation in the circulation by the body temperature. The distribution volume of injected CPK in the steady state was estimated to be approximately 4.3±1.1% of body weight. The result suggests that injected CPK is distributed into a major compartment (plasma) and a minor one (assumed to be interstitium).View full abstractDownload PDF (684K) -
ETSUKO SUZUKI, KAORU CHIHARA, KEIJI SEKIGUCHI1983 Volume 31 Issue 2 Pages 632-638
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe size reduction of chloramphenicol palmitate to a submicron level was accomplished by the freeze-drying of a solution composed of chloramphenicol palmitate and benzene. The crystal form of the resulting powder was characterized by using X-ray diffractometry, infrared spectroscopy, and differential scanning calorimetry (DSC). The first two methods showed the powder to be polymorph B, but DSC measurements indicated that it contains a trace (or seeds) of polymorph A. This was confirmed by hot-stage microscopy. The dissolution rates and solubilities of freeze-dried powders and polymorph A were determined.View full abstractDownload PDF (1179K) -
KIKUO IWAMOTO, JUN WATANABE, MASAHIKO SHIBATA, JUNJI HIRATE, SHOJI OZE ...1983 Volume 31 Issue 2 Pages 639-644
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTo assess possible factors affecting the degradative reaction of urea (ureolysis) catalyzed by urease, the in vitro stability of urea in rat urine was investigated by changing the reaction temperature and pH or amount of added urease or by masking the reaction mixture from the atmosphere. The fraction of the radioactivity spiked as 14C-urea which was decomposed to 14CO2 in rat urine at 15 and 25°C for 24 h was only about 1.5 and 3.3%, respectively, while that at 35°C was as much as 42%. The activation energy for this reaction was estimated to be approximately 25 kcal/mol. Added urease enhanced the degradation of 14C-urea, the initial apparent rate constant was proportional to the amount of the added enzyme (0.01 to 5.0 U/ml) to yield an approximate catalytic constant of 1.7×10-2 ml/U/h. When urease was added at 5.0 U/ml, the highest degree of ureolysis was observed at neutral to very slightly alkaline pH. Covering the surface of the reaction mixture of rat urine with a layer of liquid paraffin appeared to depress almost completely the capture of radioactivity as 14CO2. It is, therefore, suggested that two precautions, i.e., keeping the urine isolated from the atmosphere and keeping the metabolic cage at a temperature below 25°C, should be taken in disposition experiments with urea which involve the measurement of expiratory excretion of radioactivity.View full abstractDownload PDF (724K) -
SHIGERU FUJIWARA, SHUICHI SAKURAI, ISAO SUGIMOTO, NORIO AWATA1983 Volume 31 Issue 2 Pages 645-652
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe metabolism and lymphatic transport of γ-oryzanol in rats were investigated following oral administration of the 14C-labeled compound (triterpenyl esters of ferulic acid-3-14C). Redioactivity excreted in the urine during 72 h after oral administration was 9.8% of the dose (50 mg/kg). Unchanged γ-oryzanol was not detected at all in the urine, but an in situ intestinal absorption experiment suggested that more than 80% of the absorbed radioactivity was transferred into the mesenteric vein as an intact form, though a part was metabolized in the small intestine during absorption. Ferulic acid, dihydroferulic acid, m-hydroxyphenylpropionic acid, m-coumaric acid, m-hydroxyhippuric acid and hippuric acid were identified as the major urinary metabolites. These metabolites, with the exception of hippuric acid, were also excreted in the form of glucuronide or sulfate. The radioactivity transported into the thoracic duct was only 0.3% of the dose, and of this, more than 80% was found to be γ-oryzanol by thin-layer chromatography. From these results, it is considered that γ-oryzanol administered orally is absorbed mainly into the blood via the portal vein system, not into the lymph via the thoracic duct.View full abstractDownload PDF (796K) -
HIDENORI HAYASHI, KIYOSHI FUKUYAMA, FUMIE YAMASAKI1983 Volume 31 Issue 2 Pages 653-658
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe hypocholesterolemic effect of clofibrate (ethyl p-chlorophenoxyisobutyrate) was investigated in rats under conditions of severe hypercholesterolemia produced by administering relatively large amounts of cholesterol. The rats were fed a normal chow (control rats) or a chow containing 0.25% clofibrate (treated rats) for 14 d, then Triton WR-1339 was administered intraperitoneally (100 mg/100 g body weight). Four days after this administration, the blood cholesterol level of the control rats was markedly higher at 9335 mg/dl serum, while the level of the treated rats was about 30% lower than that of the control. The bile acid level in pooled 24-h bile was proportionally higher (about 1.3-fold) in the treated rats than that in the control. In the initial bile (within 4 h after bile duct cannulation), the bile acid level in the treated bile was 2.4 times higher than in the control bile. [4-14C] Cholesterol and 100 mg non-labeled cholesterol were injected intraperitoneally into the control and clofibratetreated rats, and the radioactivities excreted into the bile were determined. The early bile (within 8 h) of the treated rats contained 5.6-fold higher radioactivity than the control bile, and the radioactivities were largely recovered in the bile acid fraction ; scarcely any radioactivity was found in the cholesterol fraction. From these results, we conclude that one of the mechanisms by which the hypocholesterolemic effect of clofibrate is mediated is stimulation of the degradation of cholesterol, that is, stimulation of the biosynthesis of bile acids.View full abstractDownload PDF (663K) -
TOHRU KIKUCHI, SHIGETOSHI KADOTA, HISASHI SUEHARA, ARASUKE NISHI, KEIS ...1983 Volume 31 Issue 2 Pages 659-663
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo strains of earthy-musty smelling fungi, identified as Chaetomium globosum KINZE ex FR. and Botrytis cinerea PERS. ex FR., were isolated from soil samples collected at Sugadaira, Nagano Prefecture. Geosmin, having a strong earthy-musty smell, and 2-phenylethanol were detected as volatile metabolites of Chaetomium globosum, while furfural, benzaldehyde, phenylacetaldehyde, and benzyl cyanide were identified as metabolites of Botrytis cinerea. On the other hand, 2-methylisoborneol (with an earthy-muddy smell) was detected in the culture of Phormidium tenue (MENEGHINI) GOMONT, a blue-green alga isolated from water in Sengari Reservoir (Kobe City Water Supply Bureau). Another compound was also detected and identified as 2, 6-di-tert-butyl-p-benzoquinone, which would be a minor component in tap water. The present results suggest that, besides actinomycetes and blue-green algae, fungi may also be responsible for the objectionable earthy-musty odor and taste sometimes apparent in public water supplies.View full abstractDownload PDF (551K) -
ISAO KITAGAWA, HUIKANG WANG, MASAYUKI SAITO, MASAYUKI YOSHIKAWA1983 Volume 31 Issue 2 Pages 664-673
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS3-Furanmethanol β-D-glucopyranoside (1) and (+)-catechin 7-O-β-D-glucopyranoside (3) were isolated from azuki beans, the seeds of Vigna angularis (WILLD.) OHWI et OHASHI (Leguminosae) and their structures were substantiated. The saponin mixture designated as total azukisaponin was also isolated from azuki beans. By means of enzymatic hydrolysis, acidic hydrolysis, and photochemical degradation, four genuine sapogenols, which included three known sapogenols, sophoradiol (7), soyasapogenol B (8), gypsogenic acid (9), and a new sapogenol named azukisapogenol (10), were isolated from total azukisaponin and the structure of 10 was elucidated. As one of the artifact sapogenols which were liberated by acidic hydrolysis of total azukisaponin, a new sapogenol named anhydrosophoradiol (5) was isolated and its structure was elucidated.View full abstractDownload PDF (1133K) -
ISAO KITAGAWA, HUIKANG WANG, MASAYUKI SAITO, MASAYUKI YOSHIKAWA1983 Volume 31 Issue 2 Pages 674-682
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSix oleanene-oligoglycosides named azukisaponins I (1), II (2), III (3), IV (4), V, and VI were isolated from azuki beans, the seeds of Vigna angularis (WILLD.) OHWI et OHASHI (Leguminosae). Among them, the structures of azukisaponins I, II, III, and IV were elucidated as 3-O-[β-D-glucopyranosyl (1→2)-β-D-glucuronopyranosyl] sophoradiol (1), 3-O-[β-D-glucopyranosyl (1→2)-β-D-glucuronopyranosyl] soyasapogenol B (2), 3-O[β-D-glucopyranosyl (1→2)-β-D-glucuronopyranosyl] azukisapogenol (3), and 3-O-(β-D-glucopyranosyl)-28-O-[β-D-glucopyranosyl (1→6)-β-D-glucuronopyranosyl] gypsogenic acid (4), respectively on the basis of chemical and physicochemical evidence.View full abstractDownload PDF (1071K) -
ISAO KITAGAWA, HUIKANG WANG, MASAYUKI SAITO, MASAYUKI YOSHIKAWA1983 Volume 31 Issue 2 Pages 683-688
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe chemical structures of azukisaponins V (1) and VI (5), two of the six oligoglycosidic ingredients of total azukisaponin isolated from azuki beans, the seeds of Vigna angularis (WILLD.) OHWI et OHASHI (Leguminosae), were investigated. By means of photochemical degradation and chemical analyses, the structures of azukisaponins V and VI were elucidated to be 3-O-[α-L-rhamnopyranosyl (1→2)-β-D-glucopyranosyl (1→2)-β-D-glucuronopyranosyl]-soyasapogenol B (1) and 3-O-[β-D-glucopyranosyl (1→2)-β-D-glucuronopyranosyl]-29-O-[β-D-glucopyranosyl (1→6)-β-D-glucuronopyranosyl] azukisapogenol (5), respectively. Azukisaponin VI (5) is the first reported example of a 3, 29-bisdesmoside of an oleanene oligoglycoside.View full abstractDownload PDF (717K) -
ISAO KITAGAWA, HUIKANG WANG, AKIRA TAKAGI, MASAKO FUCHIDA, IWAO MIURA, ...1983 Volume 31 Issue 2 Pages 689-697
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTriterpene-oligoglycoside constituents of Astragali Radix, the root of Korean Astragalus membranaceus BUNGE (Leguminosae), were isolated. By means of enzymatic and chemical degradations, the 9, 19-cyclolanostane-type triterpene named cycloastragenol (1), which was the common genuine aglycone of ten of eleven astragalosides, and the lanost-9 (II)-ene-type counterpart named astragenol (5), which was an artifact aglycone secondarily formed from 1, were isolated. On the basis of chemical and physicochemical evidence, the structures of cycloastragenol and astragenol were elucidated as (20R, 24S)-3β, 6α, 16β, 25-tetrahydroxy-20, 24-epoxy-9, 19-cyclolanostane (1) and (20R, 24S)-3β, 6α, 16β, 25-tetrahydroxy-20, 24-epoxy-lanost-9 (11)-ene (5), respectively.View full abstractDownload PDF (1025K) -
ISAO KITAGAWA, HUIKANG WANG, MASAYUKI SAITO, AKIRA TAKAGI, MASAYUKI YO ...1983 Volume 31 Issue 2 Pages 698-708
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwelve triterpene-oligoglycosides were isolated from the glycosidic constituents of Astragali Radix, the root of Korean Astragalus membranaceus BUNGE. (Leguminosae). They were acetylastragaloside I (3), isoastragalosides I (5) and II (7), astragalosides I (4, major), II (6), III, IV (8), V, VI and VII, which contain a 9, 19-cyclolanostane cycloastragenol (1) as the aglycone, and astragaloside VIII and soyasaponin I (9), which possess an oleanene-type aglycone, soyasapogenol B. By means of chemical degradations, which included a selective cleavage method for the glucuronide linkage, and 13C-NMR examinations, the structure of astragaloside IV was elucidated as 3-O-β-D-xylopyranosyl-6-O-β-D-glucopyranosylcycloastragenol (8). In addition, the structures of five acetyl derivatives of 8 : acetylastragaloside I, astragaloside I, isoastragaloside I, astragaloside II and isoastragaloside II, were elucidated as 3-O-β-(2', 3', 4'-tri-O-acetyl)-D-xylopyranosyl- (3), 3-O-β-(2', 3'-di-O-acetyl)-D-xylopyranosyl- (4), 3-O-β-(2', 4'-di-O-acetyl)-D-xylopyranosyl- (5), 3-O-β-(2'-O-acetyl)-D-xylopyranosyl- (6) and 3-O-β-(3'-O-acetyl)-D-xylopyranosyl-6-O-β-D-glucopyranosylcycloastragenol (7), respectively.View full abstractDownload PDF (1177K) -
ISAO KITAGAWA, HUIKANG WANG, MASAYUKI SAITO, MASAYUKI YOSHIKAWA1983 Volume 31 Issue 2 Pages 709-715
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSBased on chemical and physicochemical investigations including carbon-13 nuclear magnetic resonance (13C-NMR) examinations and methylation analyses, the structures of three astragalosides, which were isolated from Astragali Radix, the root of Korean Astragalus membranaceus BUNGE (Leguminosae), were elucidated : astragaloside III is 3-O-[β-D-glucopyranosyl (1→2)-β-D-xylopyranosyl] cycloastragenol (3), astragaloside V is 3-O-[β-D-glucopyranosyl (1→2)-β-D-xylopyranosyl]-25-O-β-D-glucopyranosyl-cycloastragenol (5) and astragaloside VI is 3-O-[β-D-glucopyranosyl (1→2)-β-D-xylopyranosyl]-6-O-β-D-glucopyranosyl-cycloastragenol (6).View full abstractDownload PDF (747K) -
ISAO KITAGAWA, HUIKANG WANG, MASAYUKI YOSHIKAWA1983 Volume 31 Issue 2 Pages 716-722
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSBy means of enzymatic degradation and by application of a selective cleavage method for the glucuronide linkage, as well as by the carbon-13 nuclear magnetic resonance (13C-NMR) analysis, the structures of two astragalosides, which were isolated as two of eleven astragalosidesfrom Astragali Radix (the root of Korean Astragalus membranaceus, Leguminosae), were elucidated : astragaloside VII is 3-O-β-D-xylopyranosyl-6-O-β-D-glucopyranosyl-25-O-β-D-glucopyranosyl-cycloastragenol (4) and astragaloside VIII is 3-O-[α-L-rhamnopyranosyl (1→2)-β-D-xylopyranosyl (1→2)-β-D-glucuronopyranosyl] soyasap-ogenl B (8). Astragaloside VII (4) is an unprecedented example of a triterpene-tridesmoside.View full abstractDownload PDF (722K) -
HARUO SAIKACHI, HIDEAKI SASAKI, TOKUJIRO KITAGAWA1983 Volume 31 Issue 2 Pages 723-726
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS1-Isocyanomethyl azoles (14a-f) were synthesized by the reaction of the corresponding azoles (11a-f) with trimethylformamidomethylammonium iodide (8), followed by dehydration of the resulting 1-formamidomethyl azoles (13a-f) using phosphorus oxychloride or triphenylphosphine/carbon tetrachloride. Furthermore, 1-substituted methyl-5-piperidinomethyltetrazoles (15a-f) were prepared by means of the four-component condensation of 14a-f with formaldehyde, sodium azide, and piperidine.View full abstractDownload PDF (480K) -
YOSHIO ITOH, SETSUZO TEJIMA1983 Volume 31 Issue 2 Pages 727-729
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIn order to provide useful key intermediates for syntheses of complex oligosaccharides, anomeric 1, 2', 3', 4', 6, 6'-hexa-O-acetyl-N-acetyllactosamines (8 : α, and 9 : β) and the corresponding 3-O-benzyl ethers (5 : α, and 6 : β) were synthesized. Condensation of 1, 6-anhydro-3-O-benzyl-β-N-acetylglucosamine with acetobromogalactose by a conventional Koenigs-Knorr procedure, followed by selective acetolysis of the 1, 6-anhydro-β-linkage, provided 5 and 6. Debenzylation of 5 and 6 gave 8 and 9, respectively.View full abstractDownload PDF (453K) -
HIROSHI HARA, OSAMU HOSHINO, BUNSUKE UMEZAWA1983 Volume 31 Issue 2 Pages 730-732
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTreatment of a mixture of the p-quinol acetate (4) and aryl ethers with trifluoroacetic acid gave 8-aryl-1, 2, 3, 4-tetrahydroisoquinolines (1a-f) in good yields. Similar reaction of 4 and corypalline (3) afforded a corypalline dimer (5).View full abstractDownload PDF (400K) -
MASATOSHI YAMATO, YASUO TAKEUCHI, KUNIKO HASHIGAKI, TAKASHI HIROTA1983 Volume 31 Issue 2 Pages 733-736
Published: February 25, 1983
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe effect of the solvent on the reaction of benzoxazoline-2-thiones with alkyl halides was studied. The reaction of 1 with alkyl halides and potassium carbonate in dimethylformamide (DMF) gave the corresponding 2-alkylthiobenzoxazoles (2), but the same reaction gave 2-methoxybenzoxazoles (4a) when methanol was used in place of DMF as the solvent. On the other hand, the reaction of 1, methyl iodide, alcohol, and sodium hydride in tetrahydrofuran (THF) gave 2-[N-(dialkoxymethylene) amino] phenols (5).View full abstractDownload PDF (458K)