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Volume 41, Issue 6
Displaying 1-42 of 42 articles from this issue
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Norio HAZEMOTO, Masanobu HARADA, Shigeki SUZUKI, Fusao KAIHO, Makoto H ...1993 Volume 41 Issue 6 Pages 1003-1006
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWe previously reported that liposomes composed of phosphatidylethanolamine (PE) and fatty acid exhibited pH-dependent leakage, aggregation and fusion (N. Hazemoto, M. Harada N. Komatubara, M. Haga, and Y. Kato, Chem. Pharm. Bull., 38, 748 (1990)). In this study, we have examined the effects of phosphatidylcholine (PC) and cholesterol (Chol) on the pH-sensitivity of liposomes. Contents-leakage from liposomes was always accompanied by a change in light-scattering, suggesting that aggregation or fusion of liposomes causes the leakage. The pH-sensitivity was observed only when liposomes contained less than 32 mol% of PC. The leakage vs. pH curves shifted to the more acidic regions as the PC content of the liposomes increased, but the maximum leakage (%) did not change. The effect of cholesterol on the pH-sensitivity depended on the PC/PE ratio of the liposomes. Addition of cholesterol to PC/PE/oleic acid (OA) liposomes system induced two effects, that is, aggregation of liposomes via the reduction in PC content and the stabilization of the liposomal membrane. It was shown that pH-sensitivity can be controlled by addition of the appropriate amount of PC and/or Chol to liposomal lipids.View full abstractDownload PDF (615K) -
Setsuro SUGATA1993 Volume 41 Issue 6 Pages 1007-1011
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe reaction of 3, 4-dihydroxybenzaldehyde (LH2) and dimethyl sulfate (DMS) in forming m- and p-O-methylated products (vanillin and isovanillin, respectively) in a methanol buffer solution was studied kinetically as a chemical model of catechol-O-methyltransferase (COMT). The O-methylations, especially m-O-methylations, were catalyzed by divalent metal ions such as Cu(II), Mg(II) and Zn(II). A clear Mg(II) catalysis was observed for the first time in this medium. As Mg(II) is an important metal in the COMT catalyzed reaction in vivo, this observation is very interesting. Kinetic analyses of the present data and recalculation of a part of the previous data offered the following evidence. In Cu(II) catalysis, a 1 : 2 complex(CuL2) was more active than the 1 : 1 complex (CuL). On the other hand, in Mg(II) catalysis and Zn(II) catalysis, ML was more active than ML2. These facts show that ML2 is not always more active than ML, contrary to previous reports. Methanolysis of DMS, a significant side reaction of this model reaction, and dissociation of LH2 were studied thoroughly as bases for these kinetic analyses.View full abstractDownload PDF (704K) -
Toshiyuki KONOSU, Sadao OIDA1993 Volume 41 Issue 6 Pages 1012-1018
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSynthesis of racemic and optically active cispentacin ((-)-1) is described. Intramolecular nitrone-olefin cycloaddition of the alkenyl nitrone 7 gave cis-isoxazolidine (±)-8, which was transformed into (±)-1 by sequential reactions involving catalytic hydrogenolysis and oxidation. Similarly, the optically active nitrone (R)-22, which was derived from the ketone 15 via lipase-catalyzed hydrolysis of the acetate (±)-17, underwent intramolecular cycloaddition to give (+)-25 with high stereoselectivity (15 : 1). The cycloadduct (+)-25 was transformed in 4 steps into optically active natural cispentacin.View full abstractDownload PDF (1169K) -
Yoshiko NAGATA, Reiko YODA, Yoshikazu MATSUSHIMA1993 Volume 41 Issue 6 Pages 1019-1022
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSHPLC, 1H-NMR, MS and product analysis showed that pyridoxal hydrochloride was solvolyzed in methanol to form pyridoxal monomethylacetal. The reaction followed first order kinetics with the rate constant of 1.45×10-4s-1 at 40°C. The rate was not appreciably enhanced in the presence of an excess amount of HCl. The reaction was greatly retarded by addition of an equimolar amount of KOH. The results showed that the pyridinium-phenol species of pyridoxal hemiacetal is reactive. The reaction is responsible for the "aging" of alcoholic solutions of pyridoxal, which has caused poor reproducibility of the kinetic data for the formation of Schiff bases with amino acids.View full abstractDownload PDF (546K) -
Masateru ONO, Fumiko YAMADA, Naoki NODA, Toshio KAWASAKI, Kazumoto MIY ...1993 Volume 41 Issue 6 Pages 1023-1026
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe absolute configurations of four hydroxyfatty acids, jalapinolic acid, convolvulinolic acid, ipurolic acid and 3, 11-dihydroxyhexadecanoic acid, obtained by acid hydrolysis of various resin glycosides, have been determined to be 11S, 11S, 3S, 11S, and 3S, 11S, respectively, by Mosher's method. The R-configuration of jalapinolic acid previously defined by Horeau's method was therefore revised to S.View full abstractDownload PDF (724K) -
Nobuya KATAGIRI, Takuya SHIRAISHI, Akemi TOYOTA, Hiroshi SATO, Chikara ...1993 Volume 41 Issue 6 Pages 1027-1029
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSDeamination of an anti-human immunodeficiency virus (anti-HIV) carbocyclic adenine nucleoside, 9-[c-4, t-5-bis(hydroxymethyl)cyclopent-2-en-r-1-yl]-9H-adenine (BCA) by adenosine deaminase under a variety of pressures (1 bar-6 kbar) was investigated. It was found that, while (+)-BCA was practically unaffected, the deamination of (-)-BCA was remarkably enhanced under 4 kbar to give the corresponding (-)-hypoxanthine derivative [(-)-BCH] in nearly 100% ee.View full abstractDownload PDF (603K) -
Takaki KOIDE, Akira OTAKA, Nobutaka FUJII1993 Volume 41 Issue 6 Pages 1030-1034
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSDisulfide bonds of peptides were effectively established between S-protected cysteine residues as well as free cysteine residues by the action of dimethylsulfoxide in trifluoroacetic acid. Oxytocin and α-human calcitonin gene-related peptide were synthesized using this oxidation system. The feasibility of this method for the formation of two disulfide bridges of apamin was also examined.View full abstractDownload PDF (879K) -
Akihiro TASAKA, Norikazu TAMURA, Yoshihiro MATSUSHITA, Katsunori TERAN ...1993 Volume 41 Issue 6 Pages 1035-1042
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS(2R, 3R)-2-(2, 4-Difluorophenyl)-3-mercapto-1-(1H-1, 2, 4-triazol-1-yl)-2-butanol [(2R, 3R)-7] and its stereoisomers [(2S, 3R)-, (2S, 3S)- and (2R, 3S)-7] were prepared from the optically active oxiranes 6 by a newly developed ring-opening reaction and evaluated for antifungal activity. The thiol (2R, 3R)-7 showed extremely potent antifungal activity in vitro and in vivo.The optically active oxirane (2R, 3S)-6, a useful intermediate for the synthesis of sulfur-containing antifungal azoles 5, was synthesized from methyl (R)-lactate [(R)-8] via eight steps in a stereocontrolled manner. The key step in the synthesis is the Grignard reaction of an amide derivative [(R)-12a] of (R)-lactic acid with 2, 4-difluorophenylmagnesium bromide (13).View full abstractDownload PDF (1134K) -
Akihiro TASAKA, Norikazu TAMURA, Yoshihiro MATSUSHITA, Ryogo HAYASHI, ...1993 Volume 41 Issue 6 Pages 1043-1048
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIn an effort to find potent antifungal agents, a variety of optically active triazole derivatives with a polysulfide structure, 3, 4 and 5, were prepared and evaluated for antifungal activity against Candida albicans in vitro and in vivo. The symmetrical polysulfides 3 (m=2-4) were obtained by an oxidative coupling reaction of (2R, 3R)-2-(2, 4-difluorophenyl)-3-mercapto-1-(1H-1, 2, 4-triazol-1-yl)-2-butanol (1) or by the treatment of its thiocarbonate derivative 8 with potassium tert-butoxide. The unsymmetrical disulfides 5 were synthesized by the reaction of the thiol 1 with Bunte salts 11 or the thiosulfinate 12 or by the reaction of the thiocarbonate 8 with various thiols 13. All of these polysulfides showed potent antifungal activity against candidosis in mice.View full abstractDownload PDF (922K) -
Toshihisa OGAWA, Atsuro NAKAZATO, Katsuharu TSUCHIDA, Katsuo HATAYAMA1993 Volume 41 Issue 6 Pages 1049-1054
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWe have synthesized new 1, 4-dihydropyridine derivatives having nitrooxyalkylester moieties at the 3- and 5-positions in order to develop potent and long-lasting vasodilators. The antihypertensive activities of these compounds were compared with that of nifedipine. One of them, 2-nitrooxypropyl 3-nitrooxypropyl 2, 6-dimethyl-4-(3-nitrophenyl)-1, 4-dihydro-3, 5-pyridinedicarboxylate (CD-349) was selected for further development. The structure-activity relationship is discussed.View full abstractDownload PDF (862K) -
Atsuya IKAWA, Mikio NISHIDA, Akira OOKUBO, Yoshiyuki YOSHIMURA, Yoshih ...1993 Volume 41 Issue 6 Pages 1055-1059
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAluminum hydroxide gel (ALG), which is currently used as a phosphate-adsorbent, dissolves in gastric juice and the eluted aluminum ion has been suggested to be a causative agent of osteomalacia and encephalopathy. A new type of microcrystalline boehmite compound of aluminum oxide hydroxide with high acid resistance (named PT-A), has been developed by the author's group as a possible replacement for ALG.In the present study, the characteristic behaviors of PT-A and ALG toward various food components were compared at different pH's to get information on possible interference with phosphate adsorption onto the adsorbents by food components. The order of adsorption of food components per unit mass of PT-A was : proteins>nucleotides>lipids>carbohydrates. The order with ALG, with a minor exception, was the same as that with PT-A. However, the amounts of materials adsorbed on PT-A were generally much less than those on ALG. When phosphate was mixed with a synthetic milk as a model standard meal and exposed to the two adsorbents, phosphate-adsorption was entirely unaffected; however, the phosphate adsorption capacity of ALG was much less than that of PT-A. In conclusion, PT-A has a higher capacity for adsorbing phosphate, and adsorbs food components to a lesser extent than ALG. Phosphate-adsorption onto PT-A was not subject to interference by food components.View full abstractDownload PDF (842K) -
Yutaka KAWASHIMA, Toshihisa OGAWA, Miyuki KATO, Atsuro NAKAZATO, Katsu ...1993 Volume 41 Issue 6 Pages 1060-1065
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS1, 4-Dihydropyridine derivatives having two nitrooxyalkyl moieties as esters at the 3 and 5 positions possess antihypertensive activity. To understand how substituents affect the biological activity, the quantitative structure-activity relationship (QSAR) of 27 compounds was analyzed using the Fuzzy adaptive least-squares (FALS 91) method. The QSAR models suggested that the hydrophobicity and electronic effect at the 4 position of the 1, 4-dihydropyridine along with the special structures of the nitrooxyalkylester components are important for antihypertensive activity.View full abstractDownload PDF (740K) -
Susumu ITO, Atsutoshi OTA, Hiroshi SUHARA, Keizo TABASHI, Yoichi KAWAS ...1993 Volume 41 Issue 6 Pages 1066-1073
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIn order to search for anti-hepatitis drugs, we synthesized a series of eight- and nine-membered cyclic disulfides (1) and six- and seven-membered cyclic sulfides (2) and evaluated them for ability to reduce mortality in the model of acute hepatic failure induced by Propionibacterium acnes-lipopolysaccharide in mice. Compounds 1 were synthesized by oxidative cyclization of the corresponding dithiol derivatives (3) with diethyl bromomalonate or iodine. Compounds 2 were prepared from the methyl esters of 1 by desulfurization with tris(diethylamino)phosphine followed by deprotection. Compounds 1 were generally found to be more active than compounds 2. Compound 1b (SA3443) was found to exhibit potent protective activity. The synthesis and structure-activity relationships are discussed.View full abstractDownload PDF (986K) -
Chiaki TASHIRO, Shinro SETOGUCHI, Takemi FUKUDA, Nobuhiro MARUBAYASHI1993 Volume 41 Issue 6 Pages 1074-1078
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSMosapramine (1) is a new neuroleptic drug with an asymmetric carbon atom (8a) in its imidazopyridine ring. The enantiomers of this agent were synthesized to compare their biological activities, such as antiapomorphine activity, affinity for dopamine D2 receptor and acute toxicity. The key intermediates, (R)-(-)- and (S)-(+)-2-oxo-1, 2, 3, 5, 6, 7, 8, 8a-octahydromidazo[1, 2-a]pyridine-3-spiro-4'-piperidines, were prepared by optical resolution of the corresponding (±)-compound and were treated with 3-chloro-5-(3-methanesulfonyloxypropyl)-10, 11-dihydro-5H-dibenz[b, f]azepine to afford (R)-(-)-1 and (S)-(+)-1, respectively. There were few differences in the examined biological activities of the two enantiomers as thier dihydrochlorides.View full abstractDownload PDF (800K) -
Naoki TENO, Keiko WANAKA, Yoshio OKADA, Hiroaki TAGUCHI, Utako OKAMOTO ...1993 Volume 41 Issue 6 Pages 1079-1090
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe molecule of trans-4-aminomethylcyclohexanecarbonylphenylalanine 4-carboxymethylanilide (8), which is a potent and selective inhibitor of plasma kallikrein, can be devided into three parts (P1, P1' and P2'), each of which contains one of the rings. In order to study the role of each part in the manifestation of potent and selective inhibitory activity and the relationship between the structure and inhibitory activities toward plasmin, plasma kallikrein, urokinase and thrombin, each part was substituted with various other moieties to give many kinds of analogs and their inhibitory activities against the above enzymes were examined. Among them, trans-4-aminomethylcyclohexanecarbonyl-O-2-bromobenzyloxycarbonyltyrosine 4-acetylanilide (12) inhibited plasmin and plasma kallikrein with IC50 values of 2.3×10-7 M and 3.7×10-7 M, and Ki values of 1.2×10-7 M and 1.3×10-7 M, respectively.View full abstractDownload PDF (2251K) -
Hiroaki HAYASHI, Junichi IKEDA, Takeshi KURODA, Kazuhiro KUBO, Tomoyuk ...1993 Volume 41 Issue 6 Pages 1091-1099
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA series of 5-deoxy-5-(4-substituted piperazin-1-yl)-1, 4 : 3, 6-dianhydro-L-iditol 2-nitrates was prepared and evaluated for oral anti-ischemic activities. Inhibition of lysine-vasopressin-induced T-wave elevation in the electrocardiogram (ECG) of rats (angina pectoris model) served as a primary assay. Optimum activity was observed for the compounds with the aryl-heteroatom (O, S, or N)-propyl group. Among them, the phenylthiopropyl-substituted compound 13 exhibited the most potent activity. Furthermore, intraduodenal administration (i.d.) of 13 tended to decrease left ventricular end-diastolic pressure (LVEDP) in a propranolol-induced heart failure model (dogs) and showed a potent protective effect against reperfusion arrhythmia in rats. Thus, 13 (KF 14124) is under further study as an orally active nitrate.View full abstractDownload PDF (1160K) -
Hiroaki HAYASHI, Junichi IKEDA, Kazuhiro KUBO, Takahiro MORIYAMA, Akir ...1993 Volume 41 Issue 6 Pages 1100-1110
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA series of 5-(4-aryl- or 4-arylcarbonylpiperazin-1-yl)-5-deoxy-1, 4 : 3, 6-dianhydro-L-iditol 2-nitrates was prepared in order to obtain orally active, nitrate-type vasodilators with reduced side effects. Our drug design was based on a small reduction in the lipophilicity compared to that of 5-deoxy-5-[4-(3-phenylthiopropyl)piperazin-1-yl]-1, 4 : 3, 6-dianhydro-L-iditol 2-nitrate (1, KF14124). Compounds 4h(aryl=benzimidazol-2-yl), 4i(arylcarbonyl=nicotinoyl), and 4w(arylcarbonyl=3-furoyl) showed potent anti-ischemic activity in a lysine-vasopressin-induced angina pectoris model (rats), and their structure-activity relationships are discussed. Compound 4i exhibited potent vasodilation of the coronary artery in anesthetized dogs and also exhibited potent preload reducion in a heart failure model (dogs) as compared with isosorbide dinitrate (2), nicorandil (3), and KF14124 (1). Furthermore, 4i showed much weaker acute lethal toxicity and less central nervous system depression than 1 in mice. Thus, 4i (KW-3196) is under development as a vasodilator and a drug for treating angina pectoris.View full abstractDownload PDF (1247K) -
Katsuhito MIYAMOTO, Eigoro MURAYAMA, Kiyoshige OCHI, Hiroyoshi WATANAB ...1993 Volume 41 Issue 6 Pages 1111-1113
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFour vitamin D3 analogues (7a, 7b, 7c and 7d) bearing a hydroxyalkoxy group at the 2β-position were synthesized from the α-epoxide (5). The C-3 analogue (7b) showed the highest potency for elevating plasma calcium levels in rats. Furthermore, the 25-hydroxylated C-3 analogue (ED-71) (3), prepared from the 25-hydroxylated α-epoxide (9), significantly increased plasma calcium to levels much higher than those in rats administered 1α, 25-(OH)2-D3 (1).View full abstractDownload PDF (555K) -
Manabu HORI, Hiroshi OHTAKA1993 Volume 41 Issue 6 Pages 1114-1117
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAlkylation of 4(3H)-quinazolinones with 1-iodopentane in the presence of sodium hydride gave a mixture of 3-pentyl-4(3H)-quinazolinones (2) and 4-pentyloxyquinazolines (3). The ratio of O-alkyl/N-alkyl products varied according to the 2-substituents of the quinazoline ring. Multiple regression analyses revealed that the ratio was determined by a steric factor (width parameter of B) and an electronic factor (in terms of Hammett's σp) of the 2-substituent. It was found to be the case in the reported alkylation of 4(3H)-quinazolinones with propargyl bromide.View full abstractDownload PDF (620K) -
Munetaka ISHIYAMA, Masanobu SHIGA, Kazumi SASAMOTO, Makoto MIZOGUCHI, ...1993 Volume 41 Issue 6 Pages 1118-1122
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new tetrazolium compound, sodium salt of 4-[3-(4-iodophenyl)-2-(4-nitrophenyl)-2H-5-tetrazolio]-1, 3-benzene disulfonate (1a), which produces a highly water-soluble formazan dye, due to the presence of two sulfonate groups, was synthesized and its potential utility evaluated in assays of NADH and cell proliferation. The compound proved to have a similar sensitivity to 2, 3-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino)carbonyl]-2H-tetrazolium hydroxide (XTT) in the assay of NADH and was also useful as an indicator of cell viability, with less cytotoxicity than XTT, in the proliferation assay using P388 cell lines.View full abstractDownload PDF (788K) -
Hirofumi SUZUKI, Hiroshi NAKAGAWA, Masaki MIFUNE, Yutaka SAITO1993 Volume 41 Issue 6 Pages 1123-1126
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA plastic membrane ion-selective electrode applicable to many basic drugs has been developed. The electrode developed was constructed with tricresyl phosphate and a poly(vinyl chloride) matrix on a polytetrafluoroethylene film. The electrode showed a near-Nernstian response to chlorpromazine, trihexyphenidyl, imipramine, dibucaine, papaverine, propranolol, tetracaine, trazodone, quinidine and cinnarizine. The determination of 50 to 3000 μg/ml of trazodone hydrochloride in a pH 4.0 acetate buffer solution showed an average recovery of 99.4% (mean standard deviation 0.7%) by direct potentiometry. Inorganic cations and pharmaceutical excipients did not interfere with the determination. Trazodone hydrochloride and trihexyphenidyl hydrochloride in tablets were determined, and the results compared favorably with those obtained by conventional methods.View full abstractDownload PDF (708K) -
Hideki SAITOH, Toshio MIYASE, Akira UENO1993 Volume 41 Issue 6 Pages 1127-1131
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFrom the roots of Polygala senega var. latifolia TORR. et GRAY five new oligosaccharides, called senegoses A-E, were isolated and their structures were elucidated by spectroscopic and chemical means. These oligosaccharides were esterified with acetic, benzoic, trans-ferulic and cis-ferulic acids.View full abstractDownload PDF (652K) -
Hideki ICHIKAWA, Kaori JONO, Hiroyuki TOKUMITSU, Tomoaki FUKUDA, Yoshi ...1993 Volume 41 Issue 6 Pages 1132-1136
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe latices of copoly(ethyl acrylate-methyl methacrylate-2-hydroxyethyl methacrylate) exhibited a very low degree of agglomeration in the Wurster coating process, when the softening temperatures of their films were higher than inlet air temperature. This low agglomeration was due to their poor film-formability and, consequently, their low binding strength. Although this led to a low fixing efficiency of cosuspended solid particles, the coating efficiency of polymer itself remained high (about 90%). This low tendency of agglomeration was confirmed even in a coating of as fine a powder as 32-44 μm.View full abstractDownload PDF (796K) -
Hideo TAKAHATA, Takashi OSAWA, Masao KOBAYASHI1993 Volume 41 Issue 6 Pages 1137-1143
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe effect of drug and polymer properties on microencapsulation of acidic drugs with enteric polymers by the surface neutralization method was studied using eight benzoic acid derivatives and three enteric polymers (carboxymethylethylcellulose (CMEC), hydroxypropylmethylcellulose acetate succinate-H (AS-H) and hydroxypropylmethylcellulose acetate succinate-L (AS-L)). Each core material containing a drug was granulated to beads from 500 to 710 μm in diameter to remove the effect of drug crystal morphology. Microcapsules (MCs) were prepared by suspending the beads in an enteric polymer solution, followed by filtration and drying. Then, the properties of the MCs produced were evaluated. The polymer content in MCs (PC) and recovery percent of the drugs in MCs were in the order AS-H>AS-L>CMEC, but the percent of recovered single-nuclear MCs was in the order CMEC>AS-L>AS-H. The PCs did not correlate with the solubilities of drugs, but showed an obvious dependency on the pH of the saturated solution of the drug. That is, as the pH decreased, the PCs increased. To estimate the PCs on the basis of drug and polymer properties, a mathematical model was established on the basis of an acid-base equilibrium equation, and the ratio of polymer acidic groups associated with hydrogen ion (FS) was calculated. A linear relationship was obtained between √((FS-αp)) values (αp : equivalency ratio of hydrogen ion to acidic groups of polymer at which the polymer begins to precipitate) and the experimental PCs. Thus, microencapsulation efficiency seemed to be predictable by using this relationship.View full abstractDownload PDF (1371K) -
Yoshinobu FUKUMORI, Hideki ICHIKAWA, Hiroyuki TOKUMITSU, Masahito MIYA ...1993 Volume 41 Issue 6 Pages 1144-1148
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSMicrocapsules of hygroscopic, hyghly water-soluble gadopentetate dimeglumine (Gd-DTPA-DM) for use in preliminary in vivo experiments for neutron-capture therapy were designed. They were prepared with such properties as a particle size small enough to be suspended and injected through a syringe, a negligible release of Gd-DTPA-DM, and a high drug content by means of the Wurster process, a spray coating method using a spouted bed with a draft tube. They were composed of lactose cores of 53-63 μm, an undercoat of ethyl cellulose (EC) and polyvinylpyrrolidone (PVP), a drug-layer of Gd-DTPA-DM, EC and PVP, a waterproof coat and a release-sustaining overcoat of EC and cholesterol (1 : 1), and a surface treated with hydrogenated egg lecithin. By curing at 110°C for 30 min after mixing with 20% pulverized mannitol powder, the 20% overcoating suppressed the release of Gd-DTPA-DM from 75-106 μm microcapsules to less than 10% for the first 20 min, which was the period required to prepare a suspension, inject it and irradiate the neutron. The microcapsules could be used to confirm that the intracellular presence of Gd is not critical in gadolinium neutron-capture therapy.View full abstractDownload PDF (1428K) -
Toshiaki MORIMOTO, Mitsuo CHIBA, Kazuo ACHIWA1993 Volume 41 Issue 6 Pages 1149-1156
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSModified DIOPs, (4R, 5R)-4-(diaryl- or dialkylphosphino)methyl-5-(diarylphosphino)methyl-2, 2-dimethyl-1, 3-dioxolanes, were prepared on the basis of our design concept, and used as ligands for the rhodium(I)-catalyzed asymmetric hydrogenations of ketopantolactone, itaconic acid, demethyl itaconate, and β-aryl-substituted itaconic acid derivatives. A neutral rhodium(I)-complex of (4R-trans)-dicyclohexyl[[5-[(diphenylphosphino)methyl]-2, 2-dimethyl-1, 3-dioxolan-4-yl]methyl]phosphine (DIOCP) bearing both a dicyclohexylphosphino group and a diphenylphosphino group was found to be a more efficient catalyst than the original DIOP in the asymmetric hydrogenation of ketopantolactone. Modified DIOPs bearing electron-donating groups at their para positions were efficient ligands for the rhodium(I)-catalyzed asymmetric hydrogenations of itaconic acid and its derivatives; in particular, (4R-trans)-[(2, 2-dimethyl-1, 3-dioxolane-4, 5-diyl)bis(metylene)]bis[bis(4'-methoxy-3', 5'-dimethylphenyl)phosphine] (MOD-DIOP) bearing both a p-methoxy group and two m, m'-methyl groups on each phenyl group showed much higher enantioselectivity and catalytic activity than DIOP.View full abstractDownload PDF (1385K) -
Hirofumi OHISHI, Masafumi OGAWA1993 Volume 41 Issue 6 Pages 1157-1159
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS3, 3'-Dihydroxy-α, β-diethyldiphenylethane (I), 3, 3'-dihydroxy-α, β-diethylstilbene (II), hexestrol (III) and diethylstilbestrol (IV) have already been reported to show hypotensive effects on rats and exhibit phytogrowth-inhibitory activities. We have proposed that two phenolic hydroxyl groups in these compounds are necessary for the biological activities, and a structure-activity relationship for I-related compounds was accomplished using molecular-mechanics (MM) calculations. As a result, the following three findings were obtained; 1) the minimized conformational energy obtained from MM calculatinos, which is a parameter expressing the molecular stability, showed a relatively high correlation with the biological activities, 2) as results of quantitative structure-activity relationship (QSAR) analyses, the combination of the distance between two phenolic hydroxyl oxygens led to the regression equations with high correlation values, and 3) the idealized molecular model of the most active compound (I) showed the highest stability and had a particular conformation which differed from the other compounds (II-IV).View full abstractDownload PDF (614K) -
Mitsuhiro YOSHIMATSU, Michiyo FUJIMOTO, Hiroshi SHIMIZU, Mikio HORI, T ...1993 Volume 41 Issue 6 Pages 1160-1162
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSGeneration of α-lithio-Se, O-heteroacetals was accomplished by direct deprotonation of O-methoxyethylselenoacetals with lithium 2, 2, 6, 6-tetramethylpiperidide. Alkylation of the α-lithioheteroacetals smoothly proceeded to give the products 6 and 7. Olefinic Se, O-heteroacetals 6c and 6d were cyclized via α-seleno carbenium ions generated by selective C-O bond cleavage with titanium tetrachloride to provide the cyclohexane derivatives 8a and 8b, respectively.View full abstractDownload PDF (668K) -
Hidetoshi FUJIWARA, Ichizo OKABAYASHI1993 Volume 41 Issue 6 Pages 1163-1165
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSPyrido[3', 2' : 5, 6]pyrano[4, 3, 2-de]quinoline (1), which can be regarded as a combined structure of a xanthene analog and quinoline, was synthesized starting from 6-amino-5H-[1]benzopyrano[2, 3-b]pyridin-5-one (2).View full abstractDownload PDF (504K) -
Hisashi ISHII, Shuji OHTA, Hiromi NISHIOKA, Naomi HAYASHIDA, Takashi H ...1993 Volume 41 Issue 6 Pages 1166-1168
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA convenient and effective transformation of 2-methylbenzofuran (B) to salicylaldehyde (C) was achieved by ozonolysis of B in CH2Cl2 at -78°C followed by alkaline hydrolysis.View full abstractDownload PDF (635K) -
Hiroko SEKI, Akihiro HASHIMOTO, Tohru HINO1993 Volume 41 Issue 6 Pages 1169-1172
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe 1H- and 13C-NMR spectra of harman (2) and N-methylharman (3) have been reinvestigated, and definitive assignments of all the protons and carbons of 2 in CDCl3, DMSO-d6, and CD3OD were obtained by the use of DEPT, HC-COSY (or HMQC), COLOC (or HMBC), and CNOEDIF techniques.View full abstractDownload PDF (597K) -
Hiroko SEKI, Masako NAKAGAWA, Akihiro HASHIMOTO, Tohru HINO1993 Volume 41 Issue 6 Pages 1173-1176
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe 1H- and 13C-NMR spectra of manzamine C (1) and its analogs (2-8) have been analyzed by applying HC-COSY (or HMQC) and COLOC (or HMBC) methods. The slow ring-inversion of the piperidine part in 6 was observed at room temperature. The free energy of activation for interconversion of rotamers in the amide analog (8) was evaluated.View full abstractDownload PDF (545K) -
Nobutoshi MURAKAMI, Hideaki SHIRAHASHI, Akito NAGATSU, Jinsaku SAKAKIB ...1993 Volume 41 Issue 6 Pages 1177-1179
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo unprecedented acyl-distributed glyceroglycolipids have been isolated from the nitrogen-fixing cyanobacterium Anabaena flos-aquae f. flos-aquae. The structures were determined as (2'S)-3', 6-O-diacyl-glyceryl β-D-galactopyranoside (1) and (2'R)-2', 6-O-diacyl-glyceryl β-D-galactopyranoside (2) on the basis of physicochemical evidence. The positional distribution of fatty acid residues was elucidated by enzymatic hydrolysis using Rhizopus arrhizus lipase.View full abstractDownload PDF (662K) -
Toshiyuki KIMURA, Kazuhito WATANABE, Yuji TATEOKA, Shigemi KONDO, Ing ...1993 Volume 41 Issue 6 Pages 1180-1182
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSCentral depressant effects in mice of N3-substituted thymidines (Td) (1) were examined by intracerebroventricular (i.c.v.) injection. Nine derivatives including the methyl, ethyl, propyl, allyl, benzyl, xylyl and α-phenylethyl derivatives at the N3-position of 1 were synthesized and their pharmacological effects were evaluated by using hypnotic activity, pentobarbital-induced sleep prolongation and locomotor activity as indices for central depressant effects. At a dose of 2.0 μmol/mouse, the values of mean sleeping time induced by N3-benzylthymidine (6), N3-o-xylylthymidine (7), N3-m-xylylthymidine (8), N3-p-xylylthymidine (9), and N3-α-phenylethylthymidine (10) were 61, 30, 48, 45 and 23 min, respectively. These derivatives (2.0 μmol/mouse) prolonged pentobarbital-induced (40 mg/kg, i.p.) sleeping time. None of the alkyl (2-4) or allyl (5) derivatives exerted hypnotic activity, although the derivatives tested (2-10) significantly prolonged the pentobarbital-induced sleeping time. Compound 1 and its xylyl derivatives tested (0.25 μmol/mouse, i.c.v.) decreased locomotor activity. These results indicate that thymidine derivatives have central depressant activity, and the benzyl derivatives but not alkyl derivatives possess a hypnotic activity.View full abstractDownload PDF (607K) -
Hideji ITOKAWA, Koichi MASUYAMA, Hiroshi MORITA, Koichi TAKEYA1993 Volume 41 Issue 6 Pages 1183-1184
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFive cytostatic sesquiterpenes, desoxo-narchinol-A (1), nardosinone (2), debilon (3), nardosinonediol (4) and kanshone A (5), were isolated from the roots and rhizomes of Nardostachys chinensis (Valerianaceae). The steric structure of 1 was determined by nuclear Overhauser effects (NOEs) and the exciton chirality method. All five showed cytotoxic activity against P-388 cells and the structure-activity relationship of 1 was also discussed.View full abstractDownload PDF (469K) -
Toshikazu SEKINE, Yasuo ARAI, Fumio IKEGAMI, Yuichi FUJII, Shoichiro S ...1993 Volume 41 Issue 6 Pages 1185-1187
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new flavonol glycoside, camelliaside C, was isolated from "tea seed cake" prepared from the defatted seeds of Camellia sinensis O. KUNTZE. The structure was determined as kaempferol 3-O-β-D-galactopyranosyl-(1→2)-β-D-glucopyranoside by spectroscopic methods (FAB-MS, UV, IR, 1H- and 13C-NMR) and the enzymatic transformation of camelliaside C to astragalin. Camelliaside C showed an inhibitory effect on the arachidonate 5-lipoxygenase of RBL-1 cells (IC50 : 1.4×10-4 M) as did camelliaside A and B isolated from the same product.View full abstractDownload PDF (591K) -
Shunsaku OHTA, Yasuhiro KAMATA, Takayo INAGAKI, Yukari MASUDA, Satoshi ...1993 Volume 41 Issue 6 Pages 1188-1190
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSeveral N, N-diethyl-2-acylmethylbenzamides (6) were prepared from N, N-diethyl-2-toluamides (4), and the ketoamides (6) were easily cyclized to the corresponding 3-substituted isocoumarins (8) by heating in acetic acid or xylene. This simple procedure was applied to the synthesis of thunberginol A (1), thunberginol B (2), thunberginol F (14), and a key-intermediate (8j) for achlisocoumarin I (3).View full abstractDownload PDF (474K) -
Takuo TSUKUDA, Isao UMEDA, Kazunao MASUBUCHI, Michio SHIRAI, Nobuo SHI ...1993 Volume 41 Issue 6 Pages 1191-1193
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSRestrictinol 2 and 9, 10, 11, 12-tetrahydro-7-desmethylrestricticin (Ro 09-1571) have been synthesized from L-glucose. Ro 09-1571 showed improved in vitro antifungal activity and chemical stability as compared with Restricticin 1.View full abstractDownload PDF (471K) -
SULFOORIENTALOLS a, b, c, AND d, FOUR NEW BIOLOGICALLY ACTIVE SESQUITERPENES, FROM ALISMATIS RHIZOMAMasayuki YOSHIKAWA, Youich FUKUDA, Shoko HATAKEYAMA, Nobumitsu TANAKA, ...1993 Volume 41 Issue 6 Pages 1194-1196
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFour new sesquiterpenes, sulfoorientalols a, b, c, and d, having a sulfonic acid function were isolated from Chinese Alismatis Rhizoma. Their structures were determined on the basis of chemical and physicochemical evidence. Sulfoorientalols inhibited the contraction of isolated bladder smooth muscle induced by carbachol.View full abstractDownload PDF (521K) -
Masayuki YOSHIKAWA, Nobutoshi MURAKAMI, Yasunao INOUE, Yasuyuki KURODA ...1993 Volume 41 Issue 6 Pages 1197-1199
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSUsing a stereoselective nitromethane addition and a reductive elimination of an ethoxyethoxyl moiety with NaBH4 as key steps, two optically active pseudo-sugars, pseudo-α-D-glucopyranose and pseudo-β-D-glucopyranose, were synthesized from D-glucuronolactone in favorable overall yield. Furthermore, a biologically active pseudo-aminosugar, validamine, was synthesized via a substitution reaction for an acetoxyl group at the β-position of the nitro group in the nitrocyclitol derivative which was prepared from a synthetic intermediate of pseudo-D-glucopyranose.View full abstractDownload PDF (517K) -
Miho YAMADA, Akiko ITAI1993 Volume 41 Issue 6 Pages 1200-1202
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAn efficient automated method of searching for stable docking structures of protein-ligand complex has been developed. The method outputs several promising docking models in which protein and ligand interact favorably, covering all possible binding modes and ligand conformations. Our search method is excellent in terms of not only ease of use and speed of calculation, but also reliability and reproducibility of the docking results. It should become an indispensable tool for investigating biochemical reaction processes and designing new drug structures based on receptor structure.View full abstractDownload PDF (528K) -
Miho YAMADA, Akiko ITAI1993 Volume 41 Issue 6 Pages 1203-1205
Published: June 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe method of automated searching for stable docking structures of protein-ligand complex, which is reported in the preceding paper, was applied to a dihydrofolate reductase-inhibitor system. The usefulness of the method was confirmed by the fact that the most stable docking models accurately reproduced the crystal structures of two enzyme-inhibitor complexes.View full abstractDownload PDF (495K)
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