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Volume 45, Issue 2
Displaying 1-37 of 37 articles from this issue
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Seiki TANADA, Naohito KAWASAKI, Takeo NAKAMURA, Ikuo ABE1997 Volume 45 Issue 2 Pages 231-235
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSChlorofluorocarbon (CFC) replacements have recently been used for their lower stability and because they have carbon-hydrogen bonds, which means that their atmospheric lifetime is expected to be much shorter than those of CFCs, The adsorption properties of 1, 1, 2-trichloro-1, 2, 2-trifluoroethane (CFC113) and its replacement compounds, 1, 1-dichloro-2, 2, 2-trifluoroethane (HCFC123), 1, 1-dichloro-1-fluoroethane (HCFC141b), and 1, 1-dichloro-1, 2, 2, 3, 3-pentafluoropropane (HCFC225ca) on four kinds of activated carbons were investigated. The amount of CFC and HCFCs adsorbed on the activated carbon was concluded to depend upon the number of chloride and carbon atoms in their molecules. The adsorption isotherms of inhalational anesthetics (halothane, chloroform, enflurane, isoflurane, and methoxyflurane) on the activated carbon were measured to evaluate the action mechanism of inhalational anesthesia. The adsorption isotherms of CFC, HCFC, and the inhalational anesthetics were fitted to the Freundlich equation. The Freundlich constant N was well correlated with the minimum alveolar concentration (MAC) of the inhalational anesthetic : 1 MAC means that 50% of the patients will not move during a surgical operation. The adsorption mechanism of inhalational acesthetics on the surface of the activated carbon is concluded to be similar to the adsorption mechanism on a nerve cell. The anesthesia of CFC replacements can be estimated by the Freundlich constant N of the adsorption isotherms.View full abstractDownload PDF (707K) -
Nobuharu SHIGEMATSU, Natsuko KAYAKIRI, Satoshi OKADA, Hirokazu TANAKA1997 Volume 45 Issue 2 Pages 236-242
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTotal synthesis of the cyclic peptide lactone WS9326A, a potent tachykinin antagonist isolated from Streptomyces violaceoniger strain 9326, has been achieved via Cbz-Thr(Boc-allo-Thr-Asn-Ser(Bzl))-(E)ΔMeTyr-Leu-D-Phe-OTce, which was cyclized (Phe and allo-Thr) using an active ester method with N-hydroxysuccinimide. Finally the unique N-acyl group, the 2-(1(Z)-pentenyl)cinnamoyl moiety, was introduced onto the amino group in the Thr unit. The key step of the synthesis involves the preparation of the E-isomer of the dehydro-N-mehyltyrosine (ΔMeTyr) unit. The debenzoxylation reaction of the threo- and erythro-isomers of β-benzoxy-N-methyltyrosine drivatives gave exclusively the Z-isomer of Cbz-Thr-ΔMeTyr(MOM)-OMe, which was then converted to the desired E-isomer by photochemical isomerization of Cbz-Thr(TBDMS)-(Z)ΔMeTyr(MOM)-Leu-D-Phe-OTce at a later step.View full abstractDownload PDF (1147K) -
Takeshi KOIKE, Mituharu TANABE, Naoki TAKEUCHI, Seisho TOBINAGA1997 Volume 45 Issue 2 Pages 243-248
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSMethyl 5-(N, N-dimethylamino)-2, 4-pentadienoate (tert-aminodienylester 1) was synthesized by condensation of methyl crotonate (2) with N, N, N', N'-tetramethylmethylenediamine (3). The reactivity of 1 was investigated with methyl propiolate (4), dimethyl 2-butynedionate (5), dimethyl maleae (6), dimethyl fumarate (7), 2-buten-4-olide (8), 2-cyclohexenone (9), styrene (10), trans-β-nitrostyrene (11), 1, 4-benzoquinone (19), methyl 1, 4-naphtoquinone-5-carboxylate (21), 1, 4-naphthoquinone (24), juglone (26), 5-methoxy-1, 4-naphthoquinone (28), naphthazarin (31), and naphthazarin dimethyl ether (33). In addition, 5-(N, N-dimethylamino)-2, 4-pentadienenitrile (tert-aminodienylnitrile 37) was synthesized by condensation of crotononitrile (36) with 3. The reactivity of 37 was investigated with dimethyl 2-butynedionate (5), and 2-cyclohexenone (9).View full abstractDownload PDF (799K) -
Motomi MATSUKAWA, Toshifumi AKIZAWA, Masaaki OHIGASHI, Jennifer F. MOR ...1997 Volume 45 Issue 2 Pages 249-254
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWe have identified a novel cardiac steroid, 11, 19-epoxy-19-methoxytelocinobufagin, named marinosin (1), in the skin of the toad, Bufo marinus (L.) SCHNEIDER. The treatment of compound 1 with 50% CH3CN containing 0.1% trifluoroacetic acid yielded a 11α-hydroxyhellebrigenin (2), which has not previously been isolated from animals or plants. The structures of both compounds were established from spectral data obtained by NMR and MS, which were compared with those of a reference bufadienolide, 11α-hydroxytelocinobufagin. Compounds 1 and 2 have A/B cis and C/D cis configuration, which is characteristic of bufadienolides such as bufalin and marinobufagin. However, the stereo-structure of compound 1 was characterized by a boat form of the B ring, which is different from the chair from in typical bufadienolides such as compound 2. Compounds 1 and 2 both exhibited biological activity, as demonstrated by inhibition of Na+, K+-ATPase enzymatic activity and by inhibition of the binding of [3H]ouabain to Na+, K+-ATPase; however, marinosin (1) was a less effective inhibitor than 2, 11α-hydroxyhellebrigenin. We have identified compound 2 in toad venom, but not in the skin.View full abstractDownload PDF (876K) -
Yasushi ARAKAWA, Mika YASUDA, Masafumi OHNISHI, Shigeyuki YOSHIFUJI1997 Volume 45 Issue 2 Pages 255-259
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSLactams derived from hetero Diels-Alder adducts were stereospecifically converted into cis-2, 4-pyrrolidinedicarboxylic acid and cis-2, 5-piperidinedicarboxylic acid by ruthenium tetroxide oxidation. Optically active (2S, 4S)-(-)-2, 4-pyrrolidinedicarboxylic acid and (2R, 4R)-(+)-2, 4-pyrrolidinedicarboxylic acid were synthesized from (1S, 4R)-(+)-2-azabicyclo[2.2.1]hept-5-en-3-one and (1R, 4S)-(-)-2-azabicyclo[2.2.1]hept-5-en-3-one, respectively.View full abstractDownload PDF (844K) -
Hisayoshi KOBAYASHI, Naoko MORISAKI, Yoshitaka TAGO, Yuichi HASHIMOTO, ...1997 Volume 45 Issue 2 Pages 260-264
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA cytokinin isolated from the fluid endosperm of Cocos mucifera L. (coconut milk), accounting for more than 20% of the total cytokinin activity, was structurally analyzed by NMR techniques, mass spectrometry, and sugar analysis by high performance liquid chromatography (HPLC). The planar structure of the cytokinin was deduced from its NMR and mass spectrometric data. The structure of the sugar moiety, including its absolute structure, was determined by HPLC analysis of alditol acetates and aldononitrile acetates derived from the cytokinin. The configuration of the sugar-sugar bonds was determined by NMR, and the structure was finally identified as 14-O-{3-O-[β-D-galactopyranosyl-(1→2)-α-D-galactopyranosyl-(1→3)-α-L-arabinofuranosyl]-4-O-(α-L-arabinofuranosyl)-β-D-galactopyranosyl}-trans-zeatin riboside.View full abstractDownload PDF (714K) -
Tadashi KATAOKA, Yoshihide NAKAMURA, Harutoshi MATSUMOTO, Tetsuo IWAMA ...1997 Volume 45 Issue 2 Pages 265-271
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTricyclic benzothiazepinium salts (5) were prepared by [2+ +4] polar cycloaddition of thionium intermediates (4A), generated from corresponding α-chloro sulfides (4) and dienes in the presence of silver perchlorate. X-Ray analysis of 5a revealed that the configuration of the thiazepinone skeleton and the dihydrothiopyran ring is cis-fused.Reactions of benzothiazepinium salts (5) with NaBH4 or NaH afforded 3, 6-epithiobenzazocinone derivatives (9) in high yields by [2, 3]-sigmatropic rearrangement of an ylide intermediate (11). The stereochemistry of epithiobenzazocinone (9a) was determined by the nuclear Overhauser enhancement (NOE) technique and finally by X-ray analysis of the sulfoxide (10) derived from epithiobenzazocinone (9a) by m-chloroperbenzoic acid (MCPBA) oxidation. Alkylation of epithiobenzazocinone (9a) afforded 3-alkyl-3, 6-epithiobenzazocinones (12) with retention of the configuration at C-3. Dihydrothiopyran derivatives (13) were obtained in good yields by SmI2 reduction of benzothiazepinium salts (5).View full abstractDownload PDF (1155K) -
Hiroyuki AKITA, Isao UMEZAWA, Hiroko MATSUKURA1997 Volume 45 Issue 2 Pages 272-278
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSEnantioselective hydrolysis of water-insoluble α-acyloxy esters, (±)-5 and (±)-6, was carried out using lipases immobilized with Celite or a synthetic prepolymer (ENTP-4000 or ENT-4000) in a water-saturated organic solvent to produce chiral intermediates, (2S, 3S)-5 and (2S, 3R)-4, for the synthesis of diltiazem hydrochloride 1 and (-)-indolmycin 2, respectively. Furthermore, enantioselective hydrolysis of (±)-6 using lipid-lipase aggregates in water-saturated organic solvent was also found to give (2S, 3R)-4.View full abstractDownload PDF (950K) -
Akihiro YOKOYAMA, Tomohiko OHWADA, Shinichi SAITO, Koichi SHUDO1997 Volume 45 Issue 2 Pages 279-283
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe acidity dependence of orientation in the nitration of quinoline 1-oxide was investigated by using the trifluoromethanesulfonic acid (TFSA)-trifluoroacetic acid (TFA) system and the antimony pentafluoride (SbF5)-TFSA system. These systems provide a wider range of acidity than that of aqueous sulfuric acid. Comparison of the behavior of quinoline 1-oxide and 1-methoxyquinolinium triflate in acidic and neutral media demonstrated that O-protonated quinoline 1-oxide is nitrated at the 5- and 8-positions, and the free (unprotonated) molecule is nitrated at the 4-position. This result is consistent with theoretical expectation. It was also discovered that nitration at the 5-position increasingly predominates over that at the 8-position as the acidity is increased.View full abstractDownload PDF (853K) -
Hideo SAJI, Akira WATANABE, Yasuhiro MAGATA, Yoshiro OHMOMO, Yasushi K ...1997 Volume 45 Issue 2 Pages 284-290
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS(S)-5-Iodonicotine (4a), an (S)-nicotine analog iodinated at the 5-position of the pyridine ring, was synthesized and evaluated as a potential radiopharmaceutical for investigating brain nicotine receptors by single photon emission computerized tomography (SPECT). [125I]-(S)-5-Iodonicotine ([125I]-4a) was synthesized by the iododestannylation reaction under no-carrier-added conditions and purified by high-performance liquid chromatography (HPLC). The binding affinity of 4a for brain nicotine receptors was measured in terms of displacement of [3H]cytisine from binding sites in rat cortical membranes. The binding data revealed that the affinity of 4a was the same as that of (S)-nicotine and 80-fold higher than that of the (R)-enantiomer (4b). Biodistribution studies in mice disclosed that the brain uptake of [&lt125;>I]-4a was rapid and profound. Regional cerebral distribution studies in rats by autoradiography disclosed that the accumulation of [125I]-4a was dense in the thalamus, intermediate in the cortex and striatum, and less marked in the cerebellum. Furthermore, the administration of (S)-nicotine reduced the uptake of [125I]-4a in the thalamus and resulted in a nearly identifal level of radioactivity in the cerebellum. [125I]-(R)-5-Iodonicotine ([125I]-4b) showed more rapid washout from the brain and a less extensive regional cerebral distribution than the (S)-enantiomer ([125I]-4a). Thus, 4a bound to brain nicotine receptors in vivo, and therefore iodine-123-labeled 4a may be a potential radioligand for use in in vivo cerebral nicotinic receptor studies by SPECT.View full abstractDownload PDF (1314K) -
Toshiyuki MATSUNO, Masanobu KATO, Yoshio TSUCHIDA, Masayuki TAKAHASHI, ...1997 Volume 45 Issue 2 Pages 291-296
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTriamino-substituted 1, 3, 5-triazine derivatives were synthesized and tested for inhibitory activities against the aromatase of human lacental microsomes and the cytochrome P450 side chain cleavage of cholesterol (P450SCC) of pig adrenal mitochondria. The compounds having imidazolyl and tertiary amino groups as substituents in the 1, 3, 5-triazine ring showed significant aromatase-inhibitory activity. Among them, compounds 17, 23, 26, 27 and 28 were more active than the reference compound, CGS 16949A. The inhibitory activities of these compounds against P450SCC were much weaker than their aromatase-inhibitory activities. These compounds may be regarded as selective aromatase inhibitors.View full abstractDownload PDF (789K) -
Takayuki KOTANI, Akira ISHII, Yasuhiro NAGAKI, Yoshio TOYOMAKI, Hisash ...1997 Volume 45 Issue 2 Pages 297-304
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAccumulation of intracellular sorbitol, the product of glucose reduction catalyzed by aldose reductase (AR) [EC 1.1.1.21], is thought to be the main culprit in the development of diabetic complications. A series of 3-arylalkyl-2, 4, 5-trioxoimidazolidine-1-acetic acids was prepared and tested for inhibitory activities towards AR and aldehyde reductase (ALR) [EC 1.1.1.2]. These derivatives showed strong inhibitory activity against AR without markedly inhibiting ALR. In particular, the compounds with 3-nitrophenyl, 4-chloro-3-nitrophenyl, and chloro-substituted benzothiazolyl groups as the aryl part showed poweful AR-inhibitory activity. The chlorosubstituted benzothiazolyl compound showed an AR selectivity of more than 5000 fold.View full abstractDownload PDF (1150K) -
Tomokazu GOTO, Hiroshi SAKASHITA, Kazuki MUARKAMI, Masanori SUGIURA, T ...1997 Volume 45 Issue 2 Pages 305-311
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIn order to obtain a new, potent and selective histamine H3 receptor antagonist, chemical modifications of thioperamide, a well-known H3 receptor antagonist, were conducted. A new series of compounds has een synthesized by modifying the thiourea and cyclohexyl groups of thioperamide, and tested for H3 receptor affinity by receptor binding assay using plasma membrane from rat cerebral cortex. The thiourea group of thioperamide was found to be replaceable with a basic moiety such as formamidine or S-methylisothiourea. Replacement of the cyclohexyl group in thioperamide by a 1-adamantyl or an exo-2-norbornyl group increased the affinity for H3 receptor. Among the compounds synthesized, N-(1-adamantyl)-N', N'-[3-(4(5)-1H-imidazolyl)pentamethylene]formamidine 3f (AQ0145) showed the highest H3 receptor affinity, having a potent antagonistic activity. This compound was at least 1000-fold more active towards H3 than towards H1 and H2 receptors.View full abstractDownload PDF (1199K) -
Keisuke MIYAJIMA, Kazuo ACHIWA1997 Volume 45 Issue 2 Pages 312-320
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSNew N-acylated L-homoserine-containing non-phosphorylated and phosphorylated D-glucosamine derivatives were synthesized as mimicks of lipid A disaccharide. Some of the synthesized compounds exhibited mitogenic activity and nitric oxide (NO) productivity.View full abstractDownload PDF (1501K) -
Akihiro TASAKA, Tomoyuki KITAZAKI, Noboru TSUCHIMORI, Yoshihiro MATSUS ...1997 Volume 45 Issue 2 Pages 321-326
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS2-[(1R, 2R)-2-(2, 4-Difluorophenyl)-2-hydroxy-1-lmethyl-3-(1H-1, 2, 4-triazol-1-yl)propyl]-4-[4-(2, 2, 3, 3-tetrafluoropropoxy)phenyl]-3(2H, 4H)-1, 2, 4-triazolone [(1R, 2R)-1 : TAK-187] is a new antifungal agent selected as a candidate for clinical trials. The three stereoisomers [(1S, 2S)-, (1R, 2S)- and (1S, 2R)-1] of this compound were prepared to clarify the relationship between the stereochemistry and the biological activities. In vitro and in vivo assays of antifungal activity revealed that TAK-187 [(1R, 2R)-1] is the most potent among the four stereoisomers. Furthermore, TAK-187 was found to exert a strong and selective inhibitory effect on the sterol synthesis in Candida albicans as compared with that in rat liver.View full abstractDownload PDF (801K) -
Yasuo TAKEUCHI, Hideo TOMOZANE, Keiji MISUMI, Kuniko YATA, Teruyuki KA ...1997 Volume 45 Issue 2 Pages 327-332
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSGriseofulvin derivatives, dl-6'-demethyl-6'-ethylgriseofulvin (dl-5) and dl-6'-demethyl-6'-phenylgriseofulvin (dl-6) were prepared by application of a synthetic method developed by us. Antifungal activity of these derivatives decreased in the order of dl-griseofulvin (dl-1)>dl-5»dl-6 (inactive). The reaction of these derivatives with ethanethiol gave two types of compounds, 2'-(ethylthio)griseofulvin (15) and 4'-(ethylthio)isogriseofulvin (16). The relationship between the ratios of isolated yield of 15 and 16 and antifungal the activity of griseofulvin derivatives is discussed.View full abstractDownload PDF (944K) -
Minoru OKADA, Toru YODEN, Eiji KAWAMINAMI, Yoshiaki SHIMADA, Masafumi ...1997 Volume 45 Issue 2 Pages 333-337
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS1-N, N-Disubstituted amino-1H-1, 2, 4-triazole derivatives were prepared and evaluated for aromatase-inhibitory activity (in vitro) and for the inhibitory activity on pregnant mare serum gonadotropin (PMSG)-induced estrogen synthesis (in vivo). 1-N-para-Substituted benzylamino derivatives, having an electron-withdrawing group on the phenyl moiety, exhibited aromatase-inhibitory activity in vitro and in vivo. Among them, -[(4-nitrobenzyl)(4-nitrophenyl)amino]-1H-1, 2, 4-triazole (5b) was the most potent aromatase inhibitor. These 1-N-benzylamino derivatives also showed relatively strong inhibitory activity on aldosterone synthesis, indicating that the selectivity of these derivatives for aromatase inhibition was not sufficient in comparison with that of the 4-amino-4H-1, 2, 4-triazole derivatives.View full abstractDownload PDF (686K) -
Kimihiko YOSHII1997 Volume 45 Issue 2 Pages 338-343
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTo establish conditions for differential scanning calorimetry (DSC) purity analysis, problems of instrumental differences, sample size, heating rate and details of the calculation of such analysis were examined. Two kinds of DSC instruments were used to examine instrumental differences, and changing the sample size or heating rate resulted in a difference in the effect of purity value between these two instruments. The analytical region in the linearization of the van't Hoff plot influenced the purity result, while calibration of the heat resistance using indium had little effect. A calculation without a eutectic peak area caused an overestimation of the purity.According to the above examination, the appropriate conditions for purity determination with our instruments were 1.0±0.1 mg sample size, 2.0°C/min heating rate and the linearizing region in the van't Hoff plot 10-50% of peak height. Applying this technique to some doped model drugs, acetaminophen, nicotinamide and ethenzamide, impurities of under 2mol% were accurately estimated except for acetaminophen. Acetaminophen was unsuitable for this method, because overlap of the melting peak and the other phase transitions was detected by modulated DSC.View full abstractDownload PDF (858K) -
Ichiro KOSHIISHI, Hiromitsu TAKAYAMA, Norio AIMI, Kentaro YAMAGUCHI, H ...1997 Volume 45 Issue 2 Pages 344-348
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIt is generally known that carbamyl phosphate, a precursor of nucleotides, spontaneously degrades to cyanate in organisms. In the present study, we revealed the presence of an alkaline-labile cyanate-derivative in Solanum tuberosum L., which released cyanate in alkaline solution, and elucidated that it was a reaction product of cyanate with dehydroascorbate. The reaction mechanism was revealed as follows : dehydroascorbate existing as a hemiacetal form in neutral aolution reacts with cyanate to produce ultimately a spiro-compound consisted of hemiacetal and oxazolidone rings. The structure of the end product was identified by spectroscopic and X-ray analyses using a synthetic compound. This fact demonstrates that this reaction is a novel metabolic pathway of endogenous cyanate in organisms.View full abstractDownload PDF (669K) -
Victor H. CASTRO, Erick EAMIREZ, Gerardo A. MORA, Yukiko IWASE, Tsunea ...1997 Volume 45 Issue 2 Pages 349-358
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSix bisdesmosidic bayogenin saponins, named tacacosides A1, A2, B1, B2, B3 and C, were isolated from the fruit and aerial parts of Sechium pittieri (COGN.) C. KEFFREY and S. talamancense (WUNDERLIN) C. JEFFREY, Costa Rican cucurbitaceae plants. Their structures were elucidated based on spectral and chemical evidence as follows. Tacacoside A1 : 3-O-[β-D-glucopyranosyl-(1→3)-β-D-glucopyranosyl]bayogenin 28-O-{α-L-rhamnopyranosyl-(1→3)-β-D-xylopyranosyl-(1→4)-β-D-apiofuranaosyl-(1→3)]-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl} ester, tacacoside A2 : 3-O-[β-D-glucopyranosyl-(1→3)-β-D-glucopyranosyl]bayogenin 28-O-{α-L-rhamnopyranosyl-(1→3)-β-D-xylopyranosyl-(1→4)-[β-D-xylopyranosyl-(1→3)]-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl} ester, tacacoside B1 : 3-O-[β-D-glucopyranosyl]bayogenin 28-O-{α-L-rhamnopyranosyl-(1→3)-β-D-xylopyranosyl-(1→4)-[β-D-apiofuranosyl-(1→3)]-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl} ester, tacacoside B2 : 3-O-[β-D-glucopyranosyl]bayogenin 28-O-{α-L-rhamnopyranosyl-(1→3)-β-X-xylopyranosyl-(1→4)-[β-D-xylopyranosyl-(1→3)]-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl} ester, tacacoside B3 : 3-O-[β-D-glucopyranosyl-(1→3)-β-D-glucopyranosyl]bayogenin 28-O-[α-L-rhamnopyranosyl-(1→3)-β-D-xylopyranosyl-(1→4)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl] ester, and tacacoside C : 3-O-[β-D-glucopyranosyl]bayogenin 28-O-[α-L-rhamnopyranosyl-(1→3)-β-D-xylopyranosyl-(1→4)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl] ester. These saponins showed moderate antiproliferative activity (ED50 : 10-74μg/ml) against MK-1, HeLa and B16F10 cells.View full abstractDownload PDF (1515K) -
Yingli MA, Zhenkun TIAN, Haixue KUANG, Chunsheng YUAN, Chunjie SHAO, K ...1997 Volume 45 Issue 2 Pages 359-361
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo new cycloartane-type triterpenoidal saponins, huangqiyenins A and B, were isolated from the leaves of Astragalus membranaceus BUNGE (Leguminosae) collected in Heilongjiang Province, China, and established as 3-O-β-D-glucopyranosyl-(20R, 24S)-16β, 25-dihydroxy-20, 24-epoxy-9, 19-cyclolanost-6-one and 3-O-β-D-glucopyranosyl-(24S)-16β, 24, 25-trihydroxy-cyclolanost-6-one, respectively, on the basis of chemical and spectral evidence.View full abstractDownload PDF (546K) -
Tomonori ARAO, Junnei KINJO, Toshihiro NOHARA, Ryuichi ISOBE1997 Volume 45 Issue 2 Pages 362-366
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFrom Puerariae Radix, the root of Pueraria lobata (Leguminosae), six new oleanene-type triterpene glycoside, called kudzusaponins A1 (1), A2 (2), A4 (3), A5 (4), SA4 (5), and SB1 (6) were isolated together with kudzusaponin A3 (7), soyasaponins SA3 (8), and I (9). The structures of 1-6 were determined to be 3-O-α-L-rhamnopyranosyl-(1→2)-β-D-arabinopyranosyl-(1→2)-β-glucuronopyranosyl kudzusapogenol A 22-O-β-D-xylopyranoside, 3-O-β-D-galactopyranosyl-(1→2)-β-D-glucuronopyranosyl kudzusapogenol A, 3-O-β-D-glucopyranosyl-(1→2)-β-D-glucuranopyranosyl kudzusapogenol A, 3-O-α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranosyl-(1→2)-β-D-glucuronopyranosyl kudzusapogenol A, 3-O-β-D-glucuronopyranosyl-(1→2)-β-D-glucuronopyranosyl soyasapogenol A 22-O-α-L-arabinopyranoside, and 3-O-α-L-rhamnopyranosyl-(1→2)-β-D-galactopyranosyl-(1→2)-β-D-glucuronopyranosyl (β-fabatriosyl) soyasapogenol B 22-O-α-L-arabinopyranoside, respectively.View full abstractDownload PDF (763K) -
Takao TANAHASHI, Yukiko TAKENAKA, Miyako AKIMOTO, Aiko OKUDA, Yasuyo K ...1997 Volume 45 Issue 2 Pages 367-372
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSReinvestigation of the dried flowers of Jasminum polyanthum has led to the isolation of six new secoiridoid glucosides, jaspolyanoside, polyanoside, isojaspolyosides A, B and C, and 6"-O-β-D-glucopyranosyloleuropein, together with the known secoiridoid glucoside, angustifolioside B and flavonoid glycosides, nicotiflorine, kaempferol 3-O-(2-O-α-L-rhamnopyranosyl-β-D-galactopyranoside) and mauritianin. The structures of the new compounds were elucidated on the basis of chemical and spectroscopic evidence. Comparison of the spectral data of 6"-O-β-D-glucopyranosyloleuropein and those reported for angustifolioside A, previously recognized as 6"-O-β-D-glucopyranosyloleuropein, led to the conclusion that the structure of angustifolioside A should be revised to 5"-O-β-D-glucopyranosyloleuropein.View full abstractDownload PDF (884K) -
Tetsu MORIMURA, Yoshifumi NOBUHARA, Hayashi MATSUKURA1997 Volume 45 Issue 2 Pages 373-377
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new antibacterial fluoroquinolone derivative, orbifloxacin (ORFX), is decomposed photochemically in aqueous solution. When ORFX solution was irradiated with a chemical lamp or sunlight, three major photodegradation products were isolated by preparative HPLC. These degradation products were identified by electron-impact mass spectrometry, liquid-secondary-ion mass spectrometry and 1H-NMR spectroscopy.Moreover, the photodegradation pathway was investigated by a similar study using several fluoroquinolone derivatives which were presumed to be the intermediates of the photorection of ORFX. consequently, it was found that two main photochemical reactins, the decomposition of the dimethylpiperazinyl moiety and the elimination of the cyclopropyl group, take place in ORFX. The detected structures of photodegradation products and the photodegradation studies of the postulated intermediates suggested that the photodecomposition of the dimethylpiperazinyl ring at the 7-position and the elimination of the cyclopropyl group at the 1-position occurred concurrently with the release of fluorine at the 8-position.View full abstractDownload PDF (687K) -
Kazutaka MATSUBARA, Tetsumi IRIE, Kaneto UEKAMA1997 Volume 45 Issue 2 Pages 378-383
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSInclusion complexation of buserelin acetate, an agonist of luteinizing hormone-releasing hormone, with dimethyl-β-cyclodextrin (DM-β-CyD) in aqueous solution was studied spectroscopically and its mode of interaction was assessed. Ultraviolet absorption and circular dichroism (CD) spectroscopies indicate that the aromatic side chains of buserelin acetate, L-tryptophan and L-tyrosine residues, are incorporated into the hydrophobic environment of the DM-β-CyD cavity. Furthermore, proton and carbon-13 nuclear magnetic resonance spectroscopies suggest that in addition to the two aromatic side chains, a tertiary butyl D-serine residue is inserted into the DM-β-CyD cavity from the secondary hydroxyl side. On the other hand, the continuous variation plots for the buserelin acetate : DM-β-CyD system showed a 1 : 1 stoichiometry of the complex. Therefore, the complexation should be initiated by the inclusion of one of the three binding sites on the buserelin molecule into DM-β-CyD, which may in turn prevent the further access of the second cyclodextrin to the other binding sites, probably due to steric hindrance and/or conformation changes of the peptide. These structural features of the complex would account for the stabilizing effect of DM-β-CyD on the enzymatic degradation of buserelin acetate.View full abstractDownload PDF (1039K) -
Yoshiaki KAWASHIMA, Kouji NIWA, Hirofumi TAKEUCHI, Tomoaki HINO1997 Volume 45 Issue 2 Pages 384-388
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSLayering agglomeration of aluminum lake particles, i.e. a fine reddish pigment, was conducted by depositing them on a cored agglomerate of lactose prepared by the wet spherical agglomeration technique with a bridging liquid, i.e. water, in a dispersing medium, i.e. chloroform, under agitation. The layered agglomerates were spheronized and compacted during agglomeration. The processes of layering agglomeration and compaction are as described by the selective coalescence mechanism proposed by Kapur and a modified Kawakita's equation. It was newly found that the aluminium lake particles layered on the surface of a core agglomerate penetrated gradually into the inside of core agglomerates during agglomeration. The penetration behaviors of aluminum lake particles were represented by their relative movement coefficients, found by measuring their distributions in the agglomerate with a color measuring system. The mechanism of penetration of aluminum lake particles was discussed by referring to the tapping processes of aluminum lake and lactose powders in liquid and air.View full abstractDownload PDF (871K) -
Isamu TAKAGI, Harumi NAKASHIMA, Makiko TAKAGI, Toshihisa YOTSUYANAGI, ...1997 Volume 45 Issue 2 Pages 389-393
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe possibility of producing calcium-induced alginate gel beads as a vehicle for liposomes was explored. The maximal loading of egg phosphatidylcholine liposomes (ca. 26 nm in diameter) in a fully-cured bead (1.2 mm in radius, initial alginate concn. of 4%) was 2.9×10-6 mol/bead or ca. 18%, and the size of the bead slightly increased with an increase in liposome loading. The liposomes were well maintained within both fully-cured and washed beads. The liposome release from the fully-cured bead was much slower than that from the corresponding washed bead in a pH 7.4 releasing medium. The greater the liposome loading, the faster the release of the vesicles. The liposome release was investigated in terms of liposome loading, swelling of the gel body, calcium discharge and gel erosion, using washed beads. The liposome loading did not affect the bead erosion or calcium discharge but did the initial swelling ratio and liposome release. The results suggest that the loaded liposomes are not uniformly distributed in the bead but are rather gradually concentrated to the center. Such an inhomogeneous distribution of liposomes is possibly due to the fact that the gelation occurred instantly on the surface of the droplets, and the resulting gel network or layer acts as a semipermeable membrane for liposomes and forces the vesicles to move into deeper concentric sections as gelation proceeds to the interior. As the liposome loading increases, the forced migration might be very limited because of concentrically decreasing extra room to accommodate the vesicles in the bead.View full abstractDownload PDF (824K) -
Elisa FASANI, Mariella MELLA, Angelo ALBINI1997 Volume 45 Issue 2 Pages 394-396
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSMetyrapone (2-methyl-1, 2-di-3-pyridyl-1-propanone) undergoes α-cleavage upon irradiation in the solid state. The reaction occurs at the crystal surface, and the radicals formed in part recombine to give dipyridylketones, and in part add oxygen to give nicotinic acid and 3-(1-hydroxymethylethyl)pyridine. The crystals partially melt and the reacton continues until complete decomposition of the starting material.View full abstractDownload PDF (569K) -
Katsumi IIDA, Toshiko AOKI, Ryuichi UEGAKI, Masahiro KAJIWARA1997 Volume 45 Issue 2 Pages 397-398
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe source of oxaloacetic acid, required for the synthesis of porphyrins in Arthrobacter hyalinus, was examined by means of a feeding experiment with [1, 3-13C2]glycerol, which is transformed to pyruvic acid. A half of the carbon dioxide liberated from pyruvic acid in the formation of acetyl CoA was utilized for carboxylation of pyruvic acid to generate oxaloacetic acid.View full abstractDownload PDF (370K) -
Michael KRUGER, Ulrich BEYER, Peter SCHUMACHER, Clemens UNGER, Heike Z ...1997 Volume 45 Issue 2 Pages 399-401
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSBy attaching maleimide groups to anticancer drugs, derivatives are obtained which bind selectively to thiolated carrier proteins. Four maleimide derivatives of the anticancer drug doxorubicin were prepared in which 3-maleimidobenzoic acid or 4-maleimidophenylacetic acid was bound to the 3'-amino position of doxorubicin through a benzoyl or phenylacetyl amide bond (1 or 2) or in which 3-maleimidobenzoic acid hydrazide or 4-maleimidophenylacetic acid hydrazide was bound to the 13-keto position through a benzoyl or phenylacetyl hydrazone bond (3 or 4). The maleimide derivatives of doxorubicin were characterized by means of 13C-NMR spectroscopy, elemental analysis and mass spectrometry. In addition, the stability of the maleimide derivatives 1-4 at pH values of 5.0 and 7.4 was investigated with the aid of HPLC. The amide or hydrazone bond of 1-4 is stable at pH 7.4 whereas the hydrazone bond is acid-sensitive.View full abstractDownload PDF (557K) -
Kiyoshi IKEDA, Tsuyoshi ASAHARA, Kazuo ACHIWA, Hiroo HOSHINO1997 Volume 45 Issue 2 Pages 402-405
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSMonoglycosylceramide derivatives containing mimicks of ceramide were synthesized as cerebroside analogs from D-glucosamine or D-galactosamine derivatives and N-benzyloxycarbonyl-L-serine myristylamide by using trimethylsilyl trifluoromethanesulfonate (TMSOTf) as a promoter. The synthesized sulfated glycolipids show moderate anti-HIV-1 activities.View full abstractDownload PDF (609K) -
Yasuo TAKEUCHI, Toshiaki ODA, Ming-rong CHANG, Yoko OKAMOTO, Junko ONO ...1997 Volume 45 Issue 2 Pages 406-411
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIndolo[3, 2-b]quinoline derivatives (1) having various amine moieties were prepared and their antitumor activities against P388 leukemia in mice were evaluated, for the purpose of gaining an insight into the role of the amine moiety in the antitumor activity and searching for an effective amine moiety. Introduction of a methylene group between the phenyl group and amino or methanesulfonamido group resulted in decrease or loss of activity.View full abstractDownload PDF (918K) -
Kazuhiro KITAORI, Yoshikazu TAKEHIRA, Yoshiro FURUKAWA, Hiroshi YOSHIM ...1997 Volume 45 Issue 2 Pages 412-414
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe synthesis of (R)- and (S)-atenolol (1) was achieved in two steps starting from p-hydroxyphenylacetamide (2). Both enantiomers of the glycidyl ether 4 were synthesized from 2 and (R)- and (S)-epichlorohydrin (3) using an alkali metal hydroxide and/or BTA (benzyltrimethylammonium chloride), respectively. Subsequent treatment of 4 with isopropylamine afforded atenolol (1) with excellent enantiomeric excess (>98% ee).View full abstractDownload PDF (433K) -
Yumiko KIMURA, Toshihiro AKIHISA, Ken YASUKAWA, Sei-ichi TAKASE, Toshi ...1997 Volume 45 Issue 2 Pages 415-417
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo novel cycloartane-type triterpene alcohols possessing a monohydroxy-tetrahydrofuran ring in the side chain, cyclokirilodiol and isocyclokirilodiol, were isolated from the nonsaponifiable lipid fraction obtained from the methanolic extract of Trichosanthes kirilowii seeds. Their structures were determined as (22S, 24S)-22, 25-epoxy-24-hydroxy-5α-cycloartan-3β-ol and (22R, 24S)-22, 25-epoxy-24-hydroxy-5α-cycloartan-3β-ol, respectively, by detailed spectroscopic analyses.View full abstractDownload PDF (524K) -
Hideaki TOSA, Munekazu IINUMA, Toshiyuki TANAKA, Hiroshi NOZAKI, Shoug ...1997 Volume 45 Issue 2 Pages 418-420
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA xanthone derivative, subelliptenone F, and the related compounds showed an intensive inhibitory effect against topoisomerases I and II in in vitro experiments. These xanthones are prospective lead compounds for anticancer drugs.View full abstractDownload PDF (408K) -
Eiichi SUGINO, Shiho FUJIMORI, Satoshi HIBINO, Tominari CHOSHI, Yoshit ...1997 Volume 45 Issue 2 Pages 421-423
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new anti-angiogenic agent, 17α-acetoxy-9α-fluoro-6α-methylprogesterone (9α-fluoromedoroxyprogesterone acetate [FMPA, 9]) was synthesized in a 10-step sequence. FMPA (9) had about two orders of magnitude stronger antiangiogenic activity than medroxyprogesterone acetate (MPA), as estimated in a bioassay involving chorioallantoic membranes of growing chick embryos.View full abstractDownload PDF (470K) -
Yasuyuki ENDO, Michihiro OHNO, Shunji TAKEHANA, Paul E. DRIEDGER, Silv ...1997 Volume 45 Issue 2 Pages 424-426
Published: February 15, 1997
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWe synthesized benzolactams with hydrophobic substituents at various positions as analogs of (-)-benzolactam-V8-310 ((-)-BL-V8-310, 1) which reproduces the active conformation and biological activity of teleocidins. Structure-activity data indicate that the existence of a hydrophobic region between C-2 and C-9, and the steric factor at C-8 play critical roles in the appearance of biological activities.View full abstractDownload PDF (494K)
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