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Volume 20, Issue 5
Displaying 1-43 of 43 articles from this issue
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KEN IKEDA, YUKIHISA KURONO, TYOTARO TUKAMOTO1972 Volume 20 Issue 5 Pages 863-870
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSVarious methanesulfonic acid derivatives of four sulfonamides, which are represented generally as R'NHSO2C6H5NHCHRSO3Na wer esynthesized and their hydrolysis rates in vitro and pharmacokinetics of blood concentration change in rabbit were investigated. When R is H the hydrolysis rate is so slow that the pharmacological activity of parental sulfonamide can not be expected. When R is alkyl, phenyl or HOCH2 (CHOH)4 the derivative has fast hydrolysis rate which may promise good availability of parental sulfonamide. The effect of R on hydrolysis rate was elucidated by linear free energy relationship. The dissociation of sulfonamide group hastens the hydrolysis. Dynamic process of appearance and disappearance of parental sulfonamide in blood was quantitatively explained by a scheme which assumes two compartment models for both of the derivative and parental sulfonamide respectively.View full abstractDownload PDF (797K) -
YASUMITSU TAMURA, YOSHINOBU YOSHIMURA, YASUYUKI KITA1972 Volume 20 Issue 5 Pages 871-875
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSCurtius-type rearrangement of 3-azido-2-cyclohexen-1-ones (IIa, b) to 2-alkoxy-4, 5, 6, 7-tetrahydro-1H-azepin-4-ones (IVa, b and VIIa, b) and a novel ring contraction of IVa, b and VIIa, b to alkyl pyrrolidylideneactates (IXa, b and X) were described. The imineenamine tautomerism of IVa, b and VIIa, b were also mentioned.View full abstractDownload PDF (735K) -
YASUMITSU TAMURA, YASUYUKI KITA, JUNKO URAOKA1972 Volume 20 Issue 5 Pages 876-880
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSBeckmann rearrangement of 1, 2, 3, 4, 5, 6, 7, 8-octahydro-2, 5-dioxoquinoline oxime (Ia, b) and 1, 2, 3, 4, 5, 6, 7, 10-octahydro-2, 7-dioxoquinoline oximes (VIa, b) with PPA gives 1, 2, 3, -4, 5, 6, 7, 8, 9-nonahydro-2, 5-dioxopyrido [3, 2-c] azepine (IIa, b) and 1, 2, 3, 4, 5, 6, 7, 8, 10-nonahydro-2, 8-dioxopyrido [2, 3-d] azepine (VIIa, b), respectively. Under the same reaction conditions, 3-acetylamino-2-methyl-2-cyclohexen-1-one oxime (X) and 1-acetyl-1, 2, 3, 4, 5, 6, 7, 8-octahydro-5-oxoquinoline oxime (XIII) undergo a Semmler-Wolff aromatization to give 2-methyl-1, 3-phenylenediamine (XI) and 5-amino-1, 2, 3, 4-tetrahydroquinoline (XIV), respectively.View full abstractDownload PDF (709K) -
TSUKINAKA YAMANA, YUZO MIZUKAMI, AKIRA TSUJI, YOSHIHIRO YASUDA, KIYOSH ...1972 Volume 20 Issue 5 Pages 881-891
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe kinetics of hydrolyses of N-substituted aliphatic amides was studied spectro-photometrically in aqueous solution at 30-95°. In concentrated hydrochloric acid solution up to 2.0M, the observed rate constants were found to increase to a constant value. Activation entropies for acidic hydrolyses of N-alkyl acetamides were largely negative, ranging -18--32 e. u. The results can be explained by a bimolecular reaction mechanism in which a nucleophilic attack by water molecules on a protonated amide molecule is the rate-determining step. In alkaline hydrolyses of N-alkyl amides, the observed firstorder rate constants k1 were found to follow a kinetic equation : k1=k2 [OH-]+k3 [OH-]2. The activation entropies were largely negative in the range from -29 to -38 e. u. and their activation enthalpies were approximately 4 to 7 kcal/mole smaller than in acidic hydrolysis. The results suggest that the rate-determining step is the nucleophilic attack on amide molecule by hydroxide ions, and that hydrolyses of N-substituted acetamides, acyl-substituted amides and esters have the same reaction mechanism. Using Taft's method, polar and steric substituent effects on the rates of hydrolyses of N-substituted acetamides are also studied.View full abstractDownload PDF (959K) -
AKIRA TAKAMIZAWA, HISAO SATO, YOSHIRO SATO1972 Volume 20 Issue 5 Pages 892-900
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSReaction of simple benzothiazolium salts (V) with diethyl acylphosphonates (II) afforded ring-expanded products, 1, 4-benzothiazine derivatives (VII). In this reaction, it was found necessary to add II before triethylamine. VIIa-b were confirmed to be identical with authentic samples synthesized by the independent pathway shown in Chart 2. The reaction of 4-methylthiazolium salts (XIII) with II afforded 1 : 1 adducts (XIV), which were decomposed to corresponding 1, 4-thiazine derivatives (XV) by alkaline treatment. Treatment of 2-phenyl-3-oxo-4-benzyl-5-methyl-6-(2-acyloxy) ethyl-2, 3-dihydro-4H-1, 4-thiazine (IV) with hydrogen peroxide in acetic acid gave 2-hydroxy-2-phenyl-3-oxo-4-benzyl-5-methyl-6-(2-acyloxy) ethyl-2, 3-dihydro-4H-1, 4-thiazine (XIX).View full abstractDownload PDF (1004K) -
TAKEHIKO KATO, ATSUSHI TAKADA, TAKEO UEDA1972 Volume 20 Issue 5 Pages 901-904
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSBecause several series of compounds having amidine moieties that had been synthesized had a marked effect on influenza viruses in mice, iminoesterification by the reaction of amides with triethyloxonium fluoroborate was examined and cyclic amidines were obtained by the reaction of a lactam with triethyloxonium fluoroborate, followed by ammonolysis of resulting ethyl imidate with ammonia. Thus, five kinds of cyclic amidines and two compounds of cyclic amidines having a carboxamide moiety were obtained by this method. On the other hand, the reaction of 3-benzoylaminopropionamide with triethyloxonium fluoroborate afforded a cyclized compound, 2-phenyl-5, 6-dihydro-4 (3H)-pyrimidinone, identical with an authentic sample prepared by the method of Kametani. Thus four compounds of 2-substituted 5, 6-dihydro-4 (3H)-pyrimidinone were synthesized, but, 3-substituted benzoylaminopropionamide having a negative group on the phenyl ring did not afford any cyclized compound, but did 3-benzoylaminopropionimidate. It was considered from these results that ethylation of oxygen atom in the benzamide moiety might be essential for this cyclization.View full abstractDownload PDF (525K) -
YASUNOBU SATO, YUTAKA KOBAYASHI, TAKASHI NAGASAKI, TAKESHI OSHIMA, SEI ...1972 Volume 20 Issue 5 Pages 905-917
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSeveral (2-hydroxy-3-aminopropoxy) coumarin derivatives were synthesized from 5-, 7- and 8-hydroxycoumarin derivatives by established methods and β-adrenergic blocking activity was examined. A systematic study of the positional isomers in the coumarin derivatives showed that 5-methyl-8-(2-hydroxy-3-t-butylaminopropoxy) coumarin (XXIIa2) was most favorable as a β-adrenergic blocking agent. It was shown that the classical structure requirement prevailed, but 7-positional isomer was much less active. Resolution of XXIIa2 revealed that the 1-isomer possessed the major activity.View full abstractDownload PDF (1219K) -
MAMORU KAMIYA, YUKIO AKAHORI1972 Volume 20 Issue 5 Pages 918-921
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA semiempirical VESC-FMO-CI calculation was performed with the purpose of making a systematic survey on the π-π* electronic transitions of pteridine and its all possible amino-derivatives. The calculated data, particularly those for the singlet π-π* transition energies, were in good agreement with the observed data on both of the mono-and poly-substituted derivatives. Also, the effects of amino-substitution upon the polarization directions and upon the changes of the electron densities in going from the ground state to the lowest 1 (π, π*) state were discussed.View full abstractDownload PDF (464K) -
TSUKINAKA YAMANA, AKIRA TSUJI, YUZO MIZUKAMI1972 Volume 20 Issue 5 Pages 922-926
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSStudy of the intramolecular hydrogen bonding in 4-hydroxyvaleramide was undertaken to ascertain its correlation with the intramolecular catalyzed hydrolysis of amides. The presence of a strong intramolecular hydrogen bond in the amide was confirmed by infrared spectral analysis in chloroform solution. These results were supported by the stabilization energy obtained from the molecular orbital calculation of the configuration models of 4-hydroxyvaleramide.View full abstractDownload PDF (565K) -
MITSURU FURUKAWA, YOKO KOJIMA, SEIGORO HAYASHI1972 Volume 20 Issue 5 Pages 927-930
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSArylbiguanide reacted with benzoylacetone in the presence of proton to give eightmembered ring compound, 4-amino-2-arylamino-6-methyl-8-phenyl-1, 3, 5-triazacyclooctatetraen. p-Methoxyphenylbiguanide isolated exclusively two isomers, which were easily changed each other by heating. The structure of the compounds were discussed.View full abstractDownload PDF (561K) -
YUZURU YAMAMOTO, KEIICHI NITTA, YASUHARU OOHATA, TOSHIKO FURUKAWA1972 Volume 20 Issue 5 Pages 931-935
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new metabolite (I) was isolated from the ethionine inhibited culture fluid of Aspergillus fumigatus DH 413, without accompanying the usual toluquinone derivatives such as fumigatin and spinulosin. The chemical structure of the new metabolite was established as 4-carboxy-5, 5'-dihydroxy-3, 3'-dimethyl-diphenylether based on the chemical degradations and physical properties.View full abstractDownload PDF (654K) -
SHIGETAKA YOSHINA, ISAMU MAEBA1972 Volume 20 Issue 5 Pages 936-939
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSNitration of 4-oxo-7-chloro-4, 5-dihydrofuro [2, 3-d] pyridazine (V) with 96% sulfuric acid and fuming nitric acid gave 2-nitro-4-oxo-7-chloro-4, 5-dihydrofuro [2, 3-d] pyridazine (VII) and trans-2-nitro-3-hydroxy-4-oxo-7-chloro-2, 3, 4, 5-tetrahydrofuro [2, 3-d]-pyridazine (VIII). Nitration of V with 75% sulfuric acid and fuming nitric acid gave three products ; VII, VIII and cis-2-nitro-3-hydroxy-4-oxo-7-chloro-2, 3, 4, 5-tetrahydrofuro [2, 3-d] pyridazine (IX). The structure assignment of this trans-cis isomers were described.View full abstractDownload PDF (517K) -
TOYOKAZU KISHI, MASAYUKI MUROI, TAIKI KUSAKA, MASAO NISHIKAWA, KAZUHID ...1972 Volume 20 Issue 5 Pages 940-946
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAristeromycin, a new antibiotic isolated from the culture broth of Streptomyces citricolor, exhibits inhibition of the growth of Pyricularia oryzae and Xanthomonas oryzae. The structure of aristeromycin, apart from stereochemistry, was assumed as (A) on the basis of physicochemical and chemical properties of aristeromycin and its pentaacetate. By X-ray analysis of aristeromycin hydrobromide the assumed structure was ascertained and the absolute configuration was established as (1'R, 2'S, 3'R, 4'R)-9-[β-2'α, 3'α-dihydroxy-4'β-(hydroxymethyl) cyclopentyl] adenine.View full abstractDownload PDF (719K) -
HISASHI ICHIBAGASE, YORISHIGE IMAMURA, AKIO KINOSHITA, SHOJI KOJIMA1972 Volume 20 Issue 5 Pages 947-952
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe urinary excretion of sodium cyclamate (CHS-Na) in rabbits was accelerated by the simultaneous administration of phenylbutazone, and the excretion rate constant of CHS-Na increased in accordance with an increase in the dose of phenylbutazone. In the experiment of intestinal recirculating perfusion, phenylbutazone did not accelerate the intestinal absorption of CHS-Na in rabbits. And the competitive inhibitory effect of phenylbutazone on the binding between CHS-Na and bovine serum albumin was found in the equilibrium dialysis experiment. Accordingly, these results demonstrate that the acceleration of the urinary excretion of CHS-Na in the rabbits following simultaneous administration of phenylbutazone is attributed to the competitive inhibitory effect of phenylbutazone in the binding between CHS-Na and rabbit serum albumin.View full abstractDownload PDF (686K) -
MASASHI TOMODA, SATOMI NAKATSUKA, EIKO MINAMI1972 Volume 20 Issue 5 Pages 953-957
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe mucilage of Digenea simplex AGARDH has been isolated and subjected to partial methanolysis. Agarobiose dimethylacetal was obtained in high yield in addition to 3, 6-anhydro-L-galactose dimethylacetal, methyl D-galactoside, methyl D-xyloside and the other oligosaccharides. By acetylation of the mucilage followed by extraction with chloroform and alkali treatment, a pure polysaccharide was obtained. Partial methanolysis and methylation studies provided the evidence that the polysaccharide is mainly composed of alternately repeated units of 1, 3-linked D-galactose and 1, 4-linked 3, 6-anhydro-L-galactose, but the presences of 1, 4-linked D-xylose and sulfate ester were also found in part of it.View full abstractDownload PDF (792K) -
TOZO FUJII, TAISUKE ITAYA, SATOSHI MORO1972 Volume 20 Issue 5 Pages 958-965
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTreatment of 1-methoxy-9-methyladenine hydriodide (Ia) with hot pyridine has been found to produce 1-methylpyridinium salt (IIf) and 9-methyladenine 1-oxide (IIIf). Similarly, pyridine was ethylated with 1-ethoxy-9-benzyladenine hydriodide (Ic) to give 1-ethylpyridinium iodide (IIg : X=I) and 9-benzyladenine 1-oxide (IIIh). Benzyl alcohol was possible to be methylated with 1-methoxy-9-benzyladenine hydriodide (Ib), although yield of benzyl methyl ether was poor. Reactions of 1-benzyloxy-9-benzyladenine hydrobromide (Id) with various nucleophiles such as pyridine, aniline, C2H5S-, CH3CO2-, ethanol, and water also proceeded smoothly and yielded the corresponding benzylated products and IIIh in good yields. Benzylation of adenine with Id in N, N-dimethylacetamide at 35° furnished 3-benzyl-adenine as the major product and 9-benzyladenine and 1-benzyladenine as the minor products. The reactivities of Id toward pyridine and ethanol have been compared with those of 1-benzyloxy-9-benzyladenine perchlorate (Ie), and possible mechanisms of the alkylation with 1-alkoxyadenine derivatives (type I) are discussed.View full abstractDownload PDF (1002K) -
HIDEYO SHINDO, NOBUHIRO MIYAKOSHI, EIICHI NAKAJIMA1972 Volume 20 Issue 5 Pages 966-973
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe distribution of D- and L-14C-DOPA following oral administration in rats were investigated by means of whole-body autoradiographic technique. With a constant dose level of 10 mg/kg, the distribution patterns of the two isomers were found to be significantly different from those observed after intravenous administration and almost no uptake was shown in the brain and skeletal muscle after oral administration of L-DOPA, while a prominent accumulation after that of the D-isomer. These differences were ascribed to i) a rapid metabolic change of L-DOPA in the peripheral tissues including the gastro-intestinal tract and ii) a much slower absorption of D-DOPA than L-DOPA from intestine. It was further found that the distribution pattern of L-DOPA depends on the amount of oral dose and the brain uptake was increased markedly with increasing the dose level to higher than 50 mg/kg, which is in accord with the effective dose level of L-DOPA clinically applied in the treatment of Parkinsonism. The high accumulation of D-DOPA in the tissues such as the brain and skeletal muscle and its retention for a long period might give a possible explanation for the fact found clinically that the oral use of the DL-racemate rather than the L-isomer causes a severe side effect.View full abstractDownload PDF (1450K) -
MASAMICHI FUKUOKA, SHINSAKU NATORI1972 Volume 20 Issue 5 Pages 974-979
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe identity of bauerenol and ilexol was established. The position of the double bond in bauerenol was established at 7-position by the chromium trioxide oxidation of bauerene, isobauerene, and bauerenyl acetate. Some observations in the course of the reactions were also described.View full abstractDownload PDF (824K) -
HIKOKICHI OURA, SHOICHI NAKASHIMA, KINJI TSUKADA, YOKO OHTA1972 Volume 20 Issue 5 Pages 980-986
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIntraperitoneal administration of ginseng extract (fraction 3 or 4) to rat was found to increase the rate of synthesis of serum proteins such as albumin and γ-globulin. The incorporation rate of 3H-leucine into serum proteins was significantly increased 4 hr after the injection of fraction 3. The increased rate of protein synthesis reached a maximum about 8-12 hr after the administration and 46-49% increase in the rate of serum protein synthesis was observed. It was confirmed by immunochemical precipitation reaction that the increase in serum protein synthesis was due to the stimulation of albumin and γ-globulin synthesis. The rate declined to the control level at 20 hr following ginseng extract treatment. These observations are similar to the effect of cortisone on the liver. Although the mechanism of this increase in the rate of serum protein synthesis by ginseng extract is not known, some differences were observed in effects between fraction 4 and cortisone as follows. Induction of tryptophan pyrrolase and tyrosine transaminase, which is observed with cortisone, did not occur by fraction 4 administration. These results suggest that the observed effect of ginseng extract would not be due to the elevated concentration of adrenocortical steroids. From this point of view, this stimulating factor, which we term "prostisol"(protein synthesis stimulating factor), is active to RNA and protein syntheses when administered in vivo.View full abstractDownload PDF (845K) -
HIROSHI HIKINO, CHOHACHI KONNO, TSUNEMATSU TAKEMOTO1972 Volume 20 Issue 5 Pages 987-989
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFrom zedoary, Curcuma zedoaria (Zingiberaceae), a new sesquiterpenic dione has been isolated and designated as dehydrocurdione whose structure has been elucidated as I based on the physico-chemical and chemical evidence.View full abstractDownload PDF (411K) -
MITSUYOSHI MATSUO, TOSHIYASU MATSUO, TAKASHI DEGUCHI, YOSIHIKO KASIDA1972 Volume 20 Issue 5 Pages 990-993
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSPlatinum catalyzed hydrogen exchange reaction of ortho, meta, and para aminobenzoate with deuterium oxide was studied. Deuterium analysis was carried out by nuclea magnetic resonance (NMR) spectrometry and the NMR spectra of aminobenzoic acids and their derivatives were examined to be assigned. All the ring protons of the aminobenzoates exchanged except those ortho to the carboxylate ion. It was observed that there were ortho activation to amino group and ortho deactivation to carboxyl group in the exchange reaction.View full abstractDownload PDF (547K) -
TATSUO HAMADA, MITSUE SUZUKI, OSAMU YONEMITSU1972 Volume 20 Issue 5 Pages 994-997
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe selective reduction of peptide-ester groups in aqueous solution with sodium borohydride was examined. For the sterically hindered esters, which resist to the reduction, in particular N-acetylglycyl-L-valine methyl ester and N-acetylglycyl-L-proline methyl ester, the reduction was examined in detail under various conditions. Consequently, these esters could be reduced almost quantitatively to the corresponding alcohols, indicating the potential utility in protein chemistry.View full abstractDownload PDF (538K) -
HIDEO NAKAI, KEIJI HEMMI, TAKEO IWAKUMA, OSAMU YONEMITSU1972 Volume 20 Issue 5 Pages 998-1005
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWater soluble novel compounds, 4-azabicyclo [5, 2, 2] undeca-8, 10-dien-3-ones were synthesized on the photolysis of N-chloroacetyl derivatives of para methoxyphenethylamines (I and II). Some reactions of 4-azabicyclo [5, 2, 2] undeca-8, 10-dien-3-ones (IV, VIII and IX) in acids were examined. Compounds IV and IX bearing one and two enolether groups respectively were rearranged by hydrogen chloride treatments into 4-azatricyclo [5, 2, 2, 04, 10] undeca-8-en-3-ones (XIII, XXVI, XXVII and XXVIII). On heating of IV or IX in acetic acid, a novel fragmentation reaction took place to yield a aromatized compound, X or XXIV. On the other hand, VIII having no enol-ether group was stable to acid treatments.View full abstractDownload PDF (980K) -
KINZO NAGASAWA, AKIRA OGAMO, MARI SEKIGUCHI1972 Volume 20 Issue 5 Pages 1006-1011
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAmino acids, biogenic amines, and local anesthetics could be separated and identified by chromatography on cellulose sulfate-impregnated cellulose thin-layers. Properties of the cellulose sulfate, elution systems, and conditions suitable for the chromatography were investigated. A comparison of chromatographic results obtained for the compounds was made on between the cellulose sulfate-impregnated cellulose and the ordinary cellulose layers.View full abstractDownload PDF (640K) -
HIROTERU SAYO, SHIGEKO OZAKI, MASAICHIRO MASUI1972 Volume 20 Issue 5 Pages 1012-1016
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe title reaction in benzene gives a C-nitroso compound, tert-butanol and presumably water according to the equation : RNHOH+tert-BuOOH→R-N=O+tert-BuOH+H2O During the reaction electron spin resonance (ESR) spectra due to [chemical formula]·is observed. In the presence of a large excess of N-alkylhydroxylamine, tert-butylhydroperoxide decomposes through a 1 : 2 complex with N-alkylhydroxylamine and the activation energy of the reaction is about 12 kcal. Unless N-alkylhydroxylamine is present in fairly large excess, tert-butylhydroperoxide decomposes by direct homolysis : tert-BuOOH→tert-BuO·+HO· and the activation energy is about 33 kcal.View full abstractDownload PDF (581K) -
MASAHIKO FUJINO, SUSUMU SHINAGAWA, OSAMU NISHIMURA, TSUNEHIKO FUKUDA1972 Volume 20 Issue 5 Pages 1017-1020
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIsobornyloxycarbonyl chloride (IBOC-Cl), which is a satisfactorily stable oil, was prepared from isoborneol and phosgene. The chloride, when allowed to react with amino acids, gave the corresponding isobornyloxycarbonyl (IBOC-)-amino acids. In most cases, the IBOC-amino acids could be obtained in crystalline form and in good yields. The IBOC-amino acids are smoothly cleaved by acid-catalyzed solvolysis with trifluoroacetic acid to yield the free amino acids. Since the IBOC-Cl is much easier to prepare than t-butyloxycarbonyl chloride, the new amino-masking method is considered to be of great use in the synthesis of complicated peptides.View full abstractDownload PDF (579K) -
MASAHIKO FUJINO, SUSUMU SHINAGAWA1972 Volume 20 Issue 5 Pages 1021-1025
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSBradykinin, a nonapeptide local tissue hormone, was synthesized by the use of the isobornyloxycarbonyl (IBOC-)-protecting group for the temporary protection of the all amino groups of the intermediary peptides. During the synthesis of bradykinin, no complication occurred in the processes involving the introduction and removal of the IBOC-group, and the final synthetic hormone showed up to possess the full biological activity and appeared to be pure by chemical criterions.View full abstractDownload PDF (709K) -
SHINZO TANABE, IICHIRO KOYAHARA, NOBUYO TAKEUCHI, TAKEICHI SAKAGUCHI1972 Volume 20 Issue 5 Pages 1026-1032
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe structure of pigments derived from 2-chloro-(Pigment III) and 4-chloro-(Pigment I), and 2, 4-dichloro-1-naphthol (Pigment II), and the reactivity of some phenols and naphthols were investigated in the reaction mixture of diacetyl and 1, 1-pentamethyleneguanidine in alkaline medium. The structures of Pigments I and II were identical with 4-chloro derivative of Pigment A obtained from 1-naphthol as reported previously, and Pigment III was a para-isomer relative to the structure of Pigment I and II. It was found that Pigment III was also identical with 2-chloro derivative of Pigment B which could not be separated from 1-naphthol because of its instability. For the reactivity of phenols and naphthols, 1, 3-dihydroxy type such as 2-methyl- and 5-methyl resorcinol, 3, 5-dihydroxy benzoic acid, and 1, 3-dihydroxynaphthalene gave striking coloration in comparison with 1-naphthol, while 1, 2- or 1, 4-dihydroxy type, which is immediately oxidized to a quinone form, did not give positive coloration.View full abstractDownload PDF (844K) -
MICHIO MATSUI, MASASHI OKADA1972 Volume 20 Issue 5 Pages 1033-1040
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe nuclear magnetic resonance spectra of anomeric pairs of acetylated aryl D-glycopyranosides were measured in deuteriochloroform at 60 MHz. The shift reagent Eu (FOD)3 proved to be useful to distinguish the H-1 proton of the β-anomer and permitted the assignment of all the ring protons in some cases. The virtual long-range coupling of the H-5 proton with the H-3 proton of aryl β-D-glucopyranosiduronates was confirmed with an aid of the shift reagent. All of the acetoxy signals were well resolved by the addition of the shift reagent.View full abstractDownload PDF (929K) -
KIICHI ARAKAWA, TADASHI MIYASAKA, HIROKO OHTSUKA1972 Volume 20 Issue 5 Pages 1041-1046
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS4-Hydroxy-2-thiazolines were prepared by interrupting the Hantsch thiazole synthesis at the stage of cyclization. The chemical behavior of the tertiary amines, as well as the AB-quartet pattern at around 3.5 ppm in the NMR spectra, supported the cyclic structure (VII). Thioliminoester structure (VIIIa) proposed by M. Steude was unambiguously denied by the present paper.View full abstractDownload PDF (823K) -
YOSHIRO KOBAYASHI, ITSUMARO KUMADAKI, SHIGERU TAGUCHI, YUJI HANZAWA1972 Volume 20 Issue 5 Pages 1047-1049
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIn the reactions of (trifluoromethyl) pyridines and (trifluoromethyl) benzopyridines with sodium amide, trifluoromethyl group, which has been considered to be very stable, was substituted with amino group and an unexpected reaction was observed. We propose mechanisms for these reactions.View full abstractDownload PDF (497K) -
MASAKATSU KANEKO, BUNJI SHIMIZU1972 Volume 20 Issue 5 Pages 1050-1053
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
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KIICHIRO KAKEMI, HITOSHI SEZAKI, HIROYASU OGATA, CHIEKO NAGAI1972 Volume 20 Issue 5 Pages 1053-1058
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
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YASUMITSU TAMURA, YOSHIO SUMIDA, MASAZUMI IKEDA1972 Volume 20 Issue 5 Pages 1058-1061
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
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MORIO SETAKA, TOSHIHIKO OZAWA, TAKAO KWAN1972 Volume 20 Issue 5 Pages 1061-1063
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSDownload PDF (430K) -
AKIRA HARA, JIRO SUZUKI, MINORU SEKIYA1972 Volume 20 Issue 5 Pages 1063-1067
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSDownload PDF (705K) -
HIROSHI HIKINO, YOKO ASADA, SHIGENOBU ARIHARA, TSUNEMATSU TAKEMOTO1972 Volume 20 Issue 5 Pages 1067-1069
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSDownload PDF (472K) -
HIROSHI NAKAMURA, ZENZO TAMURA1972 Volume 20 Issue 5 Pages 1070-1078
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
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TAKAO MATSUNO, KAZUYOSHI FUJITANI, SHINOBU TAKEDA, KAZUYO YOKOTA, SEIK ...1972 Volume 20 Issue 5 Pages 1079-1082
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
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ITIRO YOSIOKA, HIROSHI YAMAUCHI, KEIKO MURATA, ISAO KITAGAWA1972 Volume 20 Issue 5 Pages 1082-1084
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
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KICHITARO TAKATORI, SUEHARU NAKANO, SHIGERU NAGATA, KAZUTADA OKUMURA, ...1972 Volume 20 Issue 5 Pages 1087
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
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HISASHI ISHII, YASUOKI MURAKAMI, KATSUHIRO HOSOYA, TOKUO FURUSE, HARUK ...1972 Volume 20 Issue 5 Pages 1088-1090
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
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HIROSHI HIKINO, TOMIHISA OHTA, YASUKO HIKINO, TSUNEMATSU TAKEMOTO1972 Volume 20 Issue 5 Pages 1090-1092
Published: May 25, 1972
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSDownload PDF (403K)
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