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Volume 37, Issue 5
Displaying 1-50 of 74 articles from this issue
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Setsuro SUGATA, Shizuko ISHIHARA, Yuko WATANABE(nee TAMANO), Yoshiko N ...1989 Volume 37 Issue 5 Pages 1143-1146
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe reaction of 3, 4-dihydroxybenzaldehyde (LH2) and dimethylsulfate (DMS) to form the m-and p-O-methylated products (vanillin and isovanillin, respectively) in aqueous 2-(N-morpholino)ethane sulfonate buffer was studied kinetically. The products were determined by means of high-performance liquid chromatography. The O-methylation occurred principally at the p-hydroxyl group in the absence of divalent metal ions. In the presence of Cu(II), the m-methylation was promoted and became predominant. Zn(II) showed a similar but less pronounced effect. The effects were explained in terms of the complex formation of LH2. The second order rate constants for the m-and p-methylation of the species, LH2, CuL and CuL2-2 by DMS were calculated. The values and their ratio for the m-/p-reactions increased in the order of LH2<CuL<CuL2-2. The reaction may serve as a chemical model for catechol-O-methyltransferase, which requires divalent metals and catalyzes the m-methylation.View full abstractDownload PDF (632K) -
Keisuke KITAMURA, Masako NOGUCHI, Chiaki NISHIYAMA, Kyoko KOBAYAKAWA, ...1989 Volume 37 Issue 5 Pages 1147-1150
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe pKa value of chlorpromazine incorporated in lecithin vesicles, denoted by pK__(av), was determined by proton nuclear magnetic resonance (1H-NMR) spectrometric titration in D2O containing 50 mM NaCl and 2.5 mM Na2B4O7·10H2O at 25°C for the drug and lipid concentrations of 1.76-3.5 mM and 20-67 mM, respectively. The pKav value was calculated from the relation between the chemical shift of the N-dimethyl signal of the incorporated chlorpromazine and the bulk pH value using a nonlinear least-squares method. Six experiments gave the mean value of pKav 8.48±0.07 (S.D.). The value was significantly lower than pKa 9.8 in D2O, which was determined by extrapolating the pKa's obtained in mixtures of methanol-d4 and D2O by the same 1H-NMR titration method. The results indicated that about 10% of chlorpromazine incorporated in lecithin vesicles was in a deprotonated free base state at physiological pH 7.5, although it was considered to be mostly in a protonated cationic state in aqueous solution of the same pH.View full abstractDownload PDF (682K) -
Katsuyki KURUMAYA, Takeo OKAZAKI, Masahiro KAJIWARA1989 Volume 37 Issue 5 Pages 1151-1154
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSRecently the amide-oxygen has been suggested to participate in the formation of the corrin ring of vitamin B12. To confirm this hypothesis, 17O-labeled aminolevulinic acid (ALA) was prepared and administered to Propionibacterium shermanii. The isolated vitamin B12 showed only broad 17O signals in the oxygen-17 nuclear magnetic resonance (17O-NMR) spectrum. However, distinct isotope-shifted peaks were observed in the 13C-NMR spectrum of vitamin B12 isolated after incorporation of [1-13C : 1, 4-18O2]ALA. Of these shifted peaks, one peak (C27) showed very low intensity. This indicates that dilution of 18O occurred at the acetyl chain of the A ring of vitamin B12. This result supports the assumption that the lactone formation of the A ring promotes the ring contraction, as proposed by Eschenmoser.View full abstractDownload PDF (591K) -
Hitoshi TONE, Masataka HIKOTA, Tatsuo HAMADA, Takao NISHI, Yuji OIKAWA ...1989 Volume 37 Issue 5 Pages 1155-1159
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSImproved syntheses are described of two segments required for the total synthesis of (9S)-9-dihydroerythronolide. A, i.e., (2S, 3R, 4S, 5R)-2, 4-dimethyl-5-(4-methoxybenzyloxy)heptane-1, 3, 4-triol corresponding to the C9-C15 subunit and (2S, 3R, 4R)-5-benzyloxy-2, 3-dimethylpentane-1, 4-diol corresponding to the C1-C5 subunit, via regio- and stereo-selective reduction of 2, 3-epoxy alcohols.View full abstractDownload PDF (932K) -
Hitoshi TONE, Takao NISHI, Yuji OIKAWA, Masataka HIKOTA, Osamu YONEMIT ...1989 Volume 37 Issue 5 Pages 1160-1166
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAs part of a study directed at the total synthesis of (9S)-9-dihydroerythronolide A, Wittig-Horner coupling was carried out between the C7-C15 segment, (2S, 3R, 4S, 5R, 6R, 7R)-3, 5-isopropylidenedioxy-7-(4-methoxybenzyloxy)-6-methoxymethoxy-2, 4, 6-trimethylnonanal synthesized from the C9-C15 triol, and the C1-C6 segment, diethyl (2RS, 4S, 5R, 6R)-6-tert-butyldimethylsilyloxy-4-(3, 4-dimethoxybenzyloxy)-2-oxo-1, 3, 5-trimethylhexylphosphonate synthesized from the C1-C5 diol, to obtain the C1-C15 enone, although the yield was poor.View full abstractDownload PDF (1198K) -
Hitoshi TONE, Takao NISHI, Yuji OIKAWA, Masataka HIKOTA, Osamu YONEMIT ...1989 Volume 37 Issue 5 Pages 1167-1172
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAs part of a study directed at the total synthesis of (9S)-9-dihydroerythronolide A, the C7-C15 sulfoxide, (2S, 3R, 4S, 5R, 6R, 7R)-3, 5-isopropylidenedioxy-7-(4-methoxybenzyloxy)-6-methoxymethoxy-1-phenylsulfinyl-2, 4, 6-trimethylnonane, was coupled with the C1-C6 aldehyde, (2R, 3S, 4S, 5R)-6-tert-butyldiphenylsilyloxy-3, 5-dimethyl-2, 4-isopropylidenedioxyhexanal, to give the C1-C15 hydroxysulfoxide, which was converted to the seco-acid via a stereocontrolled methylation at the C6 position. Macrocyclization of the seco-acid by Yamaguchi's method gave the 14-membered lactone, which was converted to (9S)-9-dihydroerythronolide A.View full abstractDownload PDF (1014K) -
Kazuo IGUCHI, Soichiro KANETA, Chieko TSUNE, Yasuji YAMADA1989 Volume 37 Issue 5 Pages 1173-1175
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSExpoxidation of clavulone II (1) with tert-butyl hydroperoxide gave stereoselectively the epoxide 2. Reaction of 2 with lithium chloride gave effectively the 10-chlorinated clavulone derivative 3a. The brominated derivative 3b and iodinated derivative 3c were also synthesized from 2. The 10-fluorinated derivative 3d was synthesized by the reaction of 2 with potassium hydrogen difluoride.View full abstractDownload PDF (654K) -
Hideaki SASAKI, Rie EGI, Kenji KAWANISHI, Tokujiro KITAGAWA, Tetsuro S ...1989 Volume 37 Issue 5 Pages 1176-1178
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo novel heterocyclophanes, dioxazolo[32](2, 5)furanometacyclophane (5) and the higher homolog (6) possessing 2, 5-bis(5-oxazolyl)furan units, were synthesized by the one-pot coupling reaction of 1, 3-bis(2-isocyano-2-tosylethyl)benzene (3) with furan-2, 5-dicarbaldehyde (4). On the basis of the variable-temperature nuclear magnetic resonance (VT-NMR) spectra of 5, the conformations in solution both at room temperature and at -18°C could be assigned as a syn form, and the energy barrier (ΔG〓) for the conformational flipping at the coalescence temperature (Tc=12°C) was determined to be 58.0 kJ/mol, which is lower than that of dioxazolo[32]metacyclophane (1a). Therefore, it was suggested that the oxygen atom of 5 with its lone pair is less bulky with respect to the conformational change than the aromatic carbon-hydrogen bond of 1a.View full abstractDownload PDF (520K) -
Kiyoshi IKEDA, Kazuo ACHIWA, Minoru SEKIYA1989 Volume 37 Issue 5 Pages 1179-1184
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSN-Benzyloxy-β-lactams were prepared from N-benzyloxyimines by reaction with ketene trimethylsilyl acetals in the presence of trimethylsilyl triflate followed by cyclization, or with lithium ester enolates in one step.View full abstractDownload PDF (837K) -
Michiyo HIZUKA, Chenglin FANG, Hiroshi SUEMUNE, Kiyoshi SAKAI1989 Volume 37 Issue 5 Pages 1185-1187
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS1, 4-Addition of organocopper reagents to γ-substituted α, β-unsaturated γ-lactones followed by intramolecular trapping of the resulted enolates afforded cis, cis-1, 2, 3-trisubstituted cyclopentanes and cyclohexanes in a stereocontrolled manner. This new cyclization reaction to cyclopentanes provides a new synthetic route to the key intermediate in the synthesis of 11-deoxyprostaglandins.View full abstractDownload PDF (580K) -
Yoshiro MATSUDA, Hiromi GOTOU, KEISUKE KATOU, Hiroshi MATSUMOTO1989 Volume 37 Issue 5 Pages 1188-1191
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSDimethyl 7-acyl-9-cyano-1-azacycl[3.3.3]azine-2, 3-dicarboxylates (4, 6) were synthesized via 1-acyl-3-cyano-4-imino-4H-quinolizines (3, 5) as key intermediates. The nucleophilic substitution of the methylthio group in antiaromatic azacycl[3.3.3]azines (6b, 9, 13) gave the corresponging producs. The reaction of 9 or 13 with methyl acetoacetate gave the fused diazacycl[3.3.3]azines (12, 16), which are examples of a new ring system.View full abstractDownload PDF (673K) -
Masaru KOBAYASHI, Katsunori OSABE1989 Volume 37 Issue 5 Pages 1192-1196
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe major cembranoid, sarcophytol A (1a), from the soft coral Sarcophyton glaucum was found to be converted to a bicyclo[9.3.0]tetradecene derivative (3a), on standing in CHCl3 solution at room temperature. Two unstable epoxides (7a and 8), obtained by autoxidation of 1a, were shown to afford 3a on further storage in CHCl3. The acetate 7b, in contrast, is stable under the same conditions and gave the dihydrofuran (9) and triol monoacetate (11) derivatives on mild alkaline and acid treatment, respectively. Five minor cembranoids of S. glaucum, having the 1, 3-diene system, were examined for the cyclization reaction by dissolving them in CHCl3. The 1, 3, 7, 11-tetraenes (2, 14, 16) gave similar bicyclotetradecene derivatives (12, 15, 17), while the 7-hydroxy 1, 3, 8(19), 11-tetraenes (18, 20) gabe the 3, 7-oxide derivatives (19, 21) in low yields.View full abstractDownload PDF (902K) -
Hiroshi FUKUMI, Mitsuo SUGIYAMA, Toshiaki SAKAMOTO1989 Volume 37 Issue 5 Pages 1197-1200
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA practical preparation of 2, 3-dihydro-5H-oxazolo[3, 2-a]thieno[3, 2-d]pyrimidin-5-oen (2) from methyl 3-aminothiophene-2-carboxylate in two steps was developed. The addition reactions of various nucleophiles to 2 were investigated and oxazole-ring-opened compounds were produced (5, 6, 12, 13 and 14). Desulfurization reaction of 2 with Raney Ni gave an oxazolo[3, 2-a]pyrimidine derivative (15). It was found that 2 showed potent anti-gastric secretion activity.View full abstractDownload PDF (725K) -
Kiyoshi TOMIOKA, Masahide TANAKA, Kenji KOGA1989 Volume 37 Issue 5 Pages 1201-1207
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTotal synthesis of (-)-β-bourbonene (3) was achieved by employing the (2+2) photocycloaddition reaction of (S)-γ-pivaloyloxymethyl-β-methyl-γ-butenolide (5e) with cyclopentenone ethyleneacetal (15). The major photoadduct (16) was readily converted to the cis, anti, cis-tricyclo[5.3.0.02, 6]decane system (22) in 70% yield. Further transformation provided the optically pure title compound (3).View full abstractDownload PDF (1289K) -
Tozo FUJII, Tohru SAITO, Tadamasa DATE1989 Volume 37 Issue 5 Pages 1208-1212
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe X-ray crystal structure of the title compound (3·TsOH) has been determined. In the crystal, this salt has the exocyclic iminium structure (type 5). The adenine moiety is almost planar, and the N(9)-C(1') bond is almost coplanar with the adenine ring. However, the N(3)-methyl group is displaced rather significantly from planarity, and the endocyclic and exocyclic angles at N(3), C(4), and N(9) notably depart from those of the usual adenosine systems. The ribose moiety is in the C(2')-endo puckering conformation and in the high-anti conformation [with the torsion angle O(1')-C(1')-N(9)-C(4), x=-72.3°] with respect to the adenine moiety.View full abstractDownload PDF (694K) -
Yoshio TAKEDA, Teruyoshi ICHIHARA, Tetsuro FUJITA, Akira UENO1989 Volume 37 Issue 5 Pages 1213-1215
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSDiterpenoid constituents of the aerial parts of Rabdosia umbrosa (MAXIM.) HARA, collected in Gotenba City and Shizuoka City were separately examined. A new compound, umbrosianin (1), has been isolated together with two known compounds, umbrosin A (2) and kamebanin (3), from the former and a new compound, rabdoumbrosanin (6) has been isolated together with four known compounds, shikoccidin (4), isodomedin (5), shikoccin (7) and rabdolatifolin (8), from the latter. The structures of the new compounds have been elucidated on the basis of spectral and chemical evidence.View full abstractDownload PDF (659K) -
Tokunaru HORIE, Yasuhiko KAWAMURA, Masao TSUKAYAMA, Shiro YOSHIZAKI1989 Volume 37 Issue 5 Pages 1216-1220
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe 5-methoxy group on 3, 5, 6, 7-tetramethoxyflavones and the 3-methoxy group on 3, 6, 7-trimethoxy-5-tosyloxyflavones were selectively cleaved with anhydrous aluminum bromide in acetonitrile under controlled conditions without the cleavage of benzyloxy groups on the B ring. By the application of these reactions, seven 3, 5-dihydroxy-6, 7-dimethoxyflavones were easily synthesized from the corresponding 3, 5, 6, 7-tetramethoxyflavones which were synthesized from 3, 6-dihydroxy-2, 4-ω-trimethoxyacetophenone by means of the Allan-Robinson reaction followed by methylation.View full abstractDownload PDF (795K) -
Taisuke ITAYA, Akemi MIZUTANI, Nobuhide WATANABE1989 Volume 37 Issue 5 Pages 1221-1225
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTreatment of 1-benzyl-7-(hydroxymethyl)wye (8) with PBr3 in the presence of Ph3P gave the phosphonium bromide 9 in good yield, Heating 9 and Me2 CHCHO (7) in MeOH in the presence of K2CO3 provided 1-benzyl-1, 4-dihydro-4, 7-dimethyl-6-(3-methyl-1-butenyl)-9H-imidazo[1, 2-a]purin-9-one (11), a positional isomer of the objective 1-benzyl-7-(3-methyl-1-butenyl)wye (5), as a major product. When the reaction was conducted in Me2NCHO at -65°C using n-BuLi as base, a 7 : 2 mixture of (E)-and (Z)-5 was obtained in good yield. Nevertheless, neither the protected amino aldehyde 18 nor 21 gave the desired olefin under similar conditions, implying poor applicability of this method to the synthesis of the fluorescent bases of phenylalanine transfer ribonucleic acids (tRNAsPhe).Compound 5 was alternatively synthesized by the Wittig reaction between 1-benzyl-7-formylwye (3) and Ph3P+CH2CHMe2 I- (4) in tetrahydrofuran as an equimolar mixture of the geometrical isomers in 50% yield. When the reaction was carried out in Me2SO at room temperature using two equivalents each of NaCH2SOMe and 4, the product, obtained in high yield, was (E)-11. The use of an equimolar amount of the base afforded (E)-5 in 26% yield. Oxidation of (E)-5 with OsO4 followed by hydrogenolysis over Pd-C gave 7-(2-hydroxy-3-methylbutyl)wye (2), a model for the minor base from rat liver tRNA.Phe.View full abstractDownload PDF (1001K) -
Yoshiro MATSUDA, Hiromi GOTOU, Keisuke KATOU, Hiroshi MATSUMOTO1989 Volume 37 Issue 5 Pages 1226-1229
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe catalytic hydrogenation of the cycl[3.3.3]azine derivative (6) or 1-azacycl[3.3.3]azine derivative (15) with PtO2 in tetrahydrofuran at atmospheric pressure gave the dihydrocyclazine derivative (10) or dodecahydro-1-azacycl[3.3.3]azine derivative (16), respectively. On the other hand, the catalytic hydrogenation of 6 or 19 in AcOH gave dodecahydrocyclazine (11) or dodecahydro-2-hydroxymethyl-1-azacyclazine (21), respectively. The catalytic hydrogenation of the hydrochloride 18 in MeOH gave methyl dodecahydro-5-methyl-1-azacycl[3.3.3]azine-2-carboxylate (20). Compounds 11, 20 and 21 should be useful as intermediates for the preparation of natural products, such as coccinelline and cernuine.View full abstractDownload PDF (579K) -
Isao KITAGAWA, Motomasa KOBAYASHI, Byeng Wha SON, Shigeki SUZUKI, Yosh ...1989 Volume 37 Issue 5 Pages 1230-1234
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTriterpene-oligoglycoside constituents, contained in the body walls and the Cuvierian tubules f the sea cucumber Holothuria pervicax (torafu-namako in Japanese), were investigated and purified in their desulfated forms. These desulfated lanostane-type triterpene tetraglycosides, designated DS-pervicoside A (7), DS-pervicoside B (8), and DS-pervicoside C (9), have antifungal activity, and their structures were determined on the basis of chemical and physicochemical evidence. The parent oligoglycosides of these desulfated tetraglycosides, named pervicosides A (10), B (11), and C (12), were shown to be the 4'-sulfates of DS-pervicosides A (7), B (8), and C (9), respectively.View full abstractDownload PDF (872K) -
Taisuke ITAYA, Tsunehiro HARADA1989 Volume 37 Issue 5 Pages 1235-1238
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAn improved synthesis of 3, 9-dimethylxanthine (2a) was achieved via the reaction of 1-methyl-5-(methylamino)-imidazole-4-carboxamide (3a) with EtOCOCl in acetate buffer (pH 5) followed by treatment with aqueous NaOH. This method was successfully applied to the synthesis of 3-methylxanthosine (2b), whose N-glycosidic bond proved to be remarkably sensitive to acidic hydrolysis : 2b underwent hydrolysis at a rate more than 1000 times faster than that of xanthosine (10) in 1.0N aqueous HCl at 25°C.View full abstractDownload PDF (820K) -
Ikuo MATSUKUMA, Shigeo YOSHIYE, Kenichi MOCHIDA, Yukio HASHIMOTO, Kiyo ...1989 Volume 37 Issue 5 Pages 1239-1244
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe 3-chloro-1-carbacephem uncleus was prepared for the first time from a 3H-1-1carbacephem compound through a sequence of reactions involving addition of thiophenol, oxidation of sulfide to sulfoxide, and α-chlorination of the sulfoxide, followed by elimination of phenylsulfinic acid. The 2-β-methyl analog was similarly prepared, but the 2α-methyl analog was not obtained.Optical resolution of the 3-chloro-1-carbacephem compound was achieved by the employment of penicillin acylase. That is, the 7-phenylacetamide derivative was enantioselectively hydrolyzed to afford the optically active 7-amino-3-chloro-1-carbacephem compound. Carbacefaclor, the carbacephem analog of cefaclor, was directly and efficiently prepared by enzymatic phenylglycylation of the recemic 7-amino-3-chloro-1-carbacephem compound by using immobilized penicillin acylase. Carbacefaclor thus prepared exhibited comparable antibacterial activity against most gram positive bacteria tested and higher activity against typical gram negative bacteria as compared with cefaclor. Moreover, carbacefaclor possessed remarkably high chemical stability.View full abstractDownload PDF (994K) -
Mikio HORI, Tatsunori IWAMURA, Eiji IMAI, Hiroshi SHIMIZU, Tadashi KAT ...1989 Volume 37 Issue 5 Pages 1245-1248
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS3-Acylthiomorphinans, 3-carbamoylthio-3-deoxydihydromorphine and 3-benzoylthio-9-aza-17-carbamorphinan were synthesized by Newman-Kwart rearrangement of the corresponding O-thiocarbamates. The analgetic activities were lower than that of pentazocine, and the opioid receptor binding affinities were very weak. These acylthiomorphinans showed low antinociceptive activity compared with corresponding sulfur-containing benzomorphans. 3-Carbamoylthiodeoxydihydromorphine had no significant analgetic activity.View full abstractDownload PDF (683K) -
Kiyoshi UKAWA, Eiko IMAMIYA, Hiroaki YAMAMOTO, Katsutoshi MIZUNO, Akih ...1989 Volume 37 Issue 5 Pages 1249-1255
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSNew antitumor alkylglycerophospholipids, in which primarily the phosphocholine moiety of the platelet activating factor (PAF) molecule was modified, were synthesized from 1-alkyl-2-substituted glycerols by introducing polar head phosphoryl groups having methylene bridges of various lengths (from 2 to 14 carbons). They were tested for PAF agonistic activity and antitumor properties. In a series of 1-octadecyl-2-acetoacetylglycerophospholipids (1a-f), an increase in the length of the methylene bridge separating the phosphate and trimethylammonio group in the polar head side chain at position 3 of the glycerol backbone resulted in a progressive decrease in PAF agonistic activity and a characteristic change in antitumor activity against human promyelocytic leukemia cells (HL-60). Maximal potency was obtained with the compound having a decamethylene bridge (1e, IC50 value=1.5 μg/ml). Thus, alkylphospholipids possessing a decanmethylene bridge and a variety of substituents at position 2 (1g-n) were synthesized. They showed potent inhibitory activity with IC50 values ranging from 0.4 to 1.9 μg/ml, depending on the nature of the 2-substituent in the phospholipid molecule. In in vivo tests of the present series of alkylglycerophospholipids (1a-n), using mice bearing sarcoma 180 and mice with mammary carcinoma MM46 (both cells and compounds were given i.p.), 1-octadecyl-2-acetoacetyl-3-glyceryl ω-trimethylammoniodecyl phosphate (1e) showed the most potent life-prolonging effect. The structure-activity relationships are discussed.View full abstractDownload PDF (1336K) -
Yoshinori NISHIKAWA, Tokuhiko SHINDO, Katsumi ISHII, Hideo NAKAMURA, T ...1989 Volume 37 Issue 5 Pages 1256-1259
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new series of oxopyridinecarboxamide derivatives 3a-g and 5a were synthesized and evaluated for their antiallergic activity. 1, 4-Dihydro-7-methyl-4-oxo-1, 8-naphthyridine-3-carboxamides 3a and 5a exhibited potent antiallergic activity (inhibitory rates of 80.7 and 88.3%, respectively, at 20mg/kg, p.o.) in the rat passive cutaneous anaphylaxis (PCA) test and also exhibited much more potent in vitro inhibitory activity than caffeic acid against the enzyme 5-lipoxygenase (5-LO). Their in vitro antihistamine activity, however, was weaker than that of ketotifen. Compounds 3a and 5a are viewed as promising candidates for antiallergic agents.View full abstractDownload PDF (612K) -
Kazuya KAMEO, Yumiko ASAMI, Kunio OGAWA, Tohru MATSUNAGA, Shiuji SAITO ...1989 Volume 37 Issue 5 Pages 1260-1267
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS2-Acetylthio-3-benzoylpropionic acid derivatives having two benzene rings or condensed-ring moieties were prepared, and tested for hypolipidemic activity in normal rats. Some of these compounds were active. 2-Acetylthio-3-[4-(phenylthio)benzoyl]propionic acid (10) and its derivatives seemed to have the most potent hypocholesterolemic activities. Compound 10 showed strong activity, especially in cholesterol-fed rats.View full abstractDownload PDF (1038K) -
Eiichi OHSUGI, Toshihiro FUJIOKA, Hiroshi HARADA, Masuhisa NAKAMURA, R ...1989 Volume 37 Issue 5 Pages 1268-1278
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS6, 7-Dichloro-2, 3-dihydro-2-benzo[b]furancarboxylic acid derivatives having a 3, 3-N, S-disubstituted-2-propenoyl group at the 5-position were prepared by alkylation of 5-(thiocarbamoyl)acetyl derivatives of the 2, 3-dihydro-2-benzo[b]furancarboxylic acid ester or by acetal exchange reaction of 5-[3, 3-bis(alkylthio)-2-propenoyl] derivatives. Synthesis of 5-[4 and/or 5-(di)substituted-4-thiazolin-2-ylidene]acetyl-2, 3-dihydro-2-benzo[b]furancarboxylic acids was also achieved by the reaction of 2-halo-1-methoxyethyl isothiocyanate with the 5-acetyl derivative in the presence of base or through sulfide contraction of 2-[((6, 7-dichloro-2-methoxycarbonyl-2, 3-dihydrobenzo[b]furan-5-yl)carbonyl)methylthio]thiazolium bromide. Some of the compounds which were synthesized showed potent natriuretic activities in rats and mice. The structure-activity relationship is also discussed.View full abstractDownload PDF (1561K) -
Hisashi MATSUNAGA, Mitsuo KATANO, Hiroshi YAMAMOTO, Masato MORI, Katsu ...1989 Volume 37 Issue 5 Pages 1279-1281
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAn antitumor-active substance was obtained from the residue of the ethyl acetate extract of red ginseng, a traditional Chinese medicine, by chromatography on a silica gel column. From the proton and carbon-13 nuclear magnetic resonance spectra, it was identified as heptadeca-1-ene-4, 6-diyne-3, 9, 10-triol (panaxytriol). The panaxytriol contents of red ginseng and white ginseng, determined by gas chromatography after solvent extraction and formation of trimethylsily derivatives, were 0.38 and 0.25 mg/g, respectively. Panaxytriol showed a growth-inhibitory activity against several tumor cell lines.View full abstractDownload PDF (527K) -
Mikio HORI, Tadashi KATAOKA, Hiroshi SHIMIZU, Eiji IMAI, Noriyuki IWAT ...1989 Volume 37 Issue 5 Pages 1282-1286
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIn order to develop analgesic compounds possessing a sulfur atom in the alicyclic ring, novel cis-fused heterocycles, [1]benzothiopyrano[3, 4-b]pyrrole derivatives (II) were synthesized via a unique cyclization reaction starting from 4-(4-methoxyphenylthio)-2-butanone (1) or 6-methoxy-3, 4-dihydro-2H-1-benzothiopyran-4-one (7).The analgesic effects of benzothiopyranopyrroles (16, 18) were measured by means of the writhing test. The phenolic derivative 18 completely inhibited the appearance of writhing at the dose of 50 mg/kg, but the methoxy derivative 16 had no analgesic effect.View full abstractDownload PDF (843K) -
Hiroshi KOHDA, Osamu TAKEDA, Seiji TANAKA, Kazuo YAMASAKI, Atsushi YAM ...1989 Volume 37 Issue 5 Pages 1287-1290
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe effect of dan-shen extract, the root of Salvia miltiorrhiza, on adenylate cyclase was investigated in both rat brain and rat erythrocytes. The EtOAc fraction of the MeOH extract was proved to have significant inhibitory activity. Potent inhibitory principles in the EtOAc fraction were isolated and identified as 4 polyphenolic acids, rosemarinic acid, lithospermic acid, and their methyl ester derivatives.View full abstractDownload PDF (553K) -
Isao KOUNO, Ayako HASHIMOTO, Nobusuke KAWANO, Chun-Shu YANG1989 Volume 37 Issue 5 Pages 1291-1292
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new triphenyl lignan, macranthol, was isolated from the pericarps of Illicium macranthum (Illiciaceae), a Chinese Illicium plant. The structure was deduced to be a trimer of C6-C3 units by the extensive application of two dimensional nuclear magnetic resonance spectroscopy, and by comparison with the structures of neolignan, honokiol and magnolol, which were isolated from Magnoliaceae Plants.View full abstractDownload PDF (429K) -
Mitsuhiko NOSE, Sakae AMAGAYA, Tadahiro TAKEDA, Yukio OGIHARA1989 Volume 37 Issue 5 Pages 1293-1296
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIn the course of studies on the metabolism of saikosaponins, which are the main constituents of Bupleurum falcatum L., nine new compounds derived from saikosaponin c were isolated. On cleavage of the glycosidic bond of saikosaponin c at 80°C in alcoholic alkali metal solution, prosaikogenins E-1, E-2, and E-3 were isolated, and their structures were elucidated as 3-O-β-D-glucopyranosyl (1→6)-β-D-glucopyranoside of saikogenin E, 3-O-α-L-rhamnopyranosyl (1→4)-β-D-glucopyranoside of saikogenin E and 3-O-β-D-glucopyranoside of saikogenin E, respectively. Furthermore, on the treatment of prosaikogenins E-1, E-2, and E-3 with 1N sulfuric acid-dioxane solution for 4h at 60°C, prosaikogenins C-1, C-2, and C-3 were formed [elucidated as 3-O-β-D-glucopyranosyl (1→6)-β-D-glucopyranoside of saikogenin C, 3-O-α-L-rhamnopyranosyl (1→4)-β-D-glucopyranoside of saikogenin C, and 3-O-β-D-glucopyranoside of saikogenin C, respectively, possessing a heteroannular diene moiety at C-11, 13(18)], together with prosaikogenins B-1, B-2, and B-3 [elucidated as 3-O-β-D-glucopyranosyl (1→6)-β-D-glucopyranoside of saikogenin B, 3-O-α-L-rhamnopyranosyl (1→4)-β-D-glucopyranoside of saikogenin B, and 3-O-β-D-glucopyranoside of saikogenin B, respectively, possessing a homoannular diene moiety at C-9(11), 12].View full abstractDownload PDF (582K) -
Johji YAMAHARA, Goro KOBAYASHI, Hisashi MATSUDA, Taiichi KATAYAMA, Haj ...1989 Volume 37 Issue 5 Pages 1297-1299
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIn the present study, scoparone isolated from Artemisia Capillaris Flos has been investigated to determine its pharmacological properties on the heart. Scoparone was found to cause the increase in coronary flow and heart rate, but did not affect cardiac output, left ventricular pressure or left ventricular work in the isolated perfused heart. Scoparone at 25 mg/kg and 50 mg/kg, p.o. had a marked inhibitory effect on the ST wave depression. Consequently it is suggested that scoparone has antianginal action.View full abstractDownload PDF (556K) -
Takehiko FUKUNAGA, Ikuko KAJIKAWA, Koichi NISHIYA, Koichi TAKEYA, Hide ...1989 Volume 37 Issue 5 Pages 1300-1303
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe chemical constituents of the Japanese mistletoe, Viscum album L. var. coloratum OHWI, grown on 12 different kinds of host trees, were examined. Two new flavonoid glycosides, rhamnazin-3, 4'-di-O-glucoside and (2S)-homoeriodictyol-7-O-[apiosyl(1→2)]glucoside, were isolated from the n-BuOH extract. Two known flavonoid glycosides, flavoyadorinin-B and homo-flavoyadorinin-B, were also isolated. Moreover, comparative studies of the contents of three flavonoid glycosides in the Japanese mistletoe grown on the different host trees were carried out by high performance liquid chromatography. Flavonoid glycosides common to Japanese and European mistletoes were not found.View full abstractDownload PDF (680K) -
Taketsune MIYAHARA, Yoshio TAKINO1989 Volume 37 Issue 5 Pages 1304-1306
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new metallofluorescent indicator (N-(2-naphthyl)ethylenediamine-N, N', N'-triacetic acid, (NEDTA)) was synthesized. Its possible applications are discussed.NEDTA was synthesized in a high yield from 2-naphthol, and was stable in NaHCO3 alkaline solution. The acid dissociation constants of NEDTA determined by paper electrophoresis and potentiometry, were 2.2±0.1 (pKa1), 3.95±0.1 (pKa2), and 9.21±0.01 (pKa3). The fluorescence of NEDTA was quenched by various metal ions and NEDTA was proved to be useful as an indicator for fluorophotometric titration. Using NEDTA as a metallofluorescent indicator, 5 μmol of Cd, Cu(II), Fe(III), Hg(II), Pb(II) or Zn at pH 4 to 6 or 5 μmol of Cd, Cu(II), Hg(II), Ni(II) or Zn at pH 9 to 10 was titrated with ethylenediaminetetraacetic acid (EDTA), and back titration with Zn was performed for 5 μmol of Al, Ni(II) or Th(VI) at pH 4.6. In every titration, the coefficient of variation and the error were within 0.6%.View full abstractDownload PDF (550K) -
Yasushi HASEBE, Jun-ichi ANZAI, Akihiko UENO, Tetsuo OSA1989 Volume 37 Issue 5 Pages 1307-1310
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe magnitude of the photoinduced membrane potential actoss poly(vinyl chloride)/spirobenzopyran membranes doped with nonactin or valinomycin depended considerably upon the kind and the concentration of alkali-metal and NH+4 cations in the aqueous solution adjacent to the ultraviolet (UV)-irradiated surface of the membrane. The photoresponse was suppressed with increasing concentration of the cations. The ion-selectivity in the potentiometric photoresponse of the nonactin-entrapped membrane was in the order of NH+4>K+>Rb+>Cs+>Na+>Li+, whereas the order of selectivity of Rb+>K+>Cs+>NH+4>Na+>Li+ was ovserved for the valinomycin-doped membrane. The results can be explained in terms of the binding abilities of nonactin and valinomycin for alkali-metal and NH+4 cations.View full abstractDownload PDF (558K) -
Akimasa SHIBUKAWA, Terumichi NAKAGAWA, Mamoru MIYAKE, Naohiro NISHIMUR ...1989 Volume 37 Issue 5 Pages 1311-1315
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe effect of protein binding on the high performance liquid chromatography (HPLC) elution profile of drugs injected directly onto an internal-surface reversed-phase (ISRP) silica column was investigated. When a relatively large volume (≥100 μl) of the sample solution containing warfarin and bovine serum albumin (BSA) was applied directly onto the ISRP column and elution was carried out with the mobile phase containing an organic modifier, two distinct peaks, both due to warfarin, appeared separated from the protein peak. The peak splitting was not observed in the case of antipyrine-BSA mixed solution, where the protein binding is weak. It was found that the drug bound at the strong-binding site on the BSA molecule was released slowly during the process of chromatography and was eluted as the first peak with a shorter retention time, while the drug bound at the weak-binding site was released quickly, and was eluted as the second peak together with the free drug. The warfarin-BSA interaction at the strong-binding site was evaluated, under minimum influence from the other binding site, from the warfarin concentration obtained from the first peak and the free warfarin concentration determined by the ultrafiltration method.View full abstractDownload PDF (812K) -
Jian-Guo HU, Hideaki TANIMORI, Miwako SHIBATA, Tetsuo YOKOYAMA, Tsuneh ...1989 Volume 37 Issue 5 Pages 1316-1320
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSHighly sensitive and accurate enzyme immunoassays (EIAs), a sandwich EIA for mouse immunoglobulin G (IgG) and an enzyme linked immunosorbent assay for mouse antibody specific to viomycin (VM), were developed. Accuracy and specificity of the assay results were confirmed before their application. The changes of total IgG and antibody specific to VM in mice, immunized with a VM-immunogen with or without two types of Freund's adjuvants under various conditions, were assessed by means of the newly developed EIA methods. Both methods were very useful tools to follow the immunization processes of mice, and complete and incomplete Freund's adjuvant were found to have similar adjuvant activities for production of antibody specific to VM, judging from the amounts of anti-VM antibody formed. It seems to be important that too many booster injections should be avoided in the immunization of mice with a hapten immunogen.View full abstractDownload PDF (789K) -
Kazuhiko SAKATA, Tatunobu MAEDA, Hideo NAKAGAWA1989 Volume 37 Issue 5 Pages 1321-1323
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSRat polymorphonuclear leukocytes secrete a latent gelatinase with a molecular weight of about 96 kilodaltons (kDa). Activation of the latent 96-kDa gelatinase by cathepsin G was studied by using sodium dodecyl sulfate-substrate polyacrylamide gel electrophoresis. Cathepsin G activated the 96-kDa gelatinase by converting it to two lower molecular-weight species of 76 and 61 kDa, which were slightly different from the gelatinase species generated by treatment with 4-aminophenylmercuric acetate, an activator of latent gelatinase.View full abstractDownload PDF (773K) -
Genichiro OSHIMA1989 Volume 37 Issue 5 Pages 1324-1328
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSDextran sulfate (DS) had a greater ability to elute thrombin adsorbed on a small Sepharose 6B column than heparin did, while chondroitin sulfate A had little ability. It is probable that the strength of the interaction of thrombin depends mostly on the charge-density of strongly acidic sulfate groups in the polysaccharides. The change in intrinsic fluorescence intensity of thrombin with time was closely correlated with the rate of inactivation of the enzyme in the presence of sulfated polysaccharides. Both rates were affected by the pH of the solution in the presence of the polyanions. The rates in the presence of DS were highest at pH 6.05 among the three pHs tested, while they were enhanced only at pH 6.05 by heparin, but not by chondroitin sulfate A. Therefore, extensive charge-neutralization of thrombin by the sulfated polysaccharides is able to induce time- and temperature-dependent intramolecular conformational change (irreversible denaturation) of the enzyme molecules.View full abstractDownload PDF (819K) -
Noriko SHIMIZU, Masashi TOMODA, Ryoko GONDA, Mieko KANARI, Noriko TAKA ...1989 Volume 37 Issue 5 Pages 1329-1332
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe major acidic polysaccharide, named saposhnikovan A, was isolated from the roots and rhizomes of Saposhnikovia divaricata. It showed remarkable reticuloendothelial system-potentiating activity in a carbon clearance test. It is composed of L-arabinose : D-galactose : D-galacturonic acid in the molar ratio of 6 : 15 : 10, and its molecular weight was estimated to be 54000. About 35% of the D-galacturonic acid residues exist as the methyl esters. Methylation analysis, 13C-nuclear magnetic resonance, and controlled Smith degradation studies indicated that the polysaccharide has the α-1→4-linked D-galacturonan backbone bearing α-1→5-linked L-arabino-β-3, 6-branched D-galactan side chainsView full abstractDownload PDF (732K) -
Chantal BARTHOMEUF, Henri POURRAT, Aimee POURRAT1989 Volume 37 Issue 5 Pages 1333-1336
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA. niger LCF 9 synthesizes a new aspergillopeptidase of potential interest in therapeutics. The properties and operating range of the enzyme were determined. It is a semi-alkaline aspergillopeptidase (EC 3.4.23.4) with one endopeptidase activity. Its pI is 4.10, its molecular weight is 21000 Da and its A1%1cm at 280 nm is 9.75. It rapidly hydrolyzes casein and hemoglobin. Its optimal pH is 7.8 and optimal temperature is 45°C. It is thermally labile above 40°C but can be stabilized by adding calcium ions. It is inhibited by phenylmethylsulfonyl fluoride (PMSF), by ethylenediaminetetraacetic acid (EDTA) and by certain metals ions, e.g. copper, manganese and cobalt ions. It has no dipeptidase or tripeptidase activity and its esterase activity is weak. It has a high collagenase activity and is to our knowledge the only aspergillopeptidase that is active toward benzoyl-arginine p-nitroanilide (BAPNA).View full abstractDownload PDF (683K) -
Toshihiro OHMORI, Kohji TAMURA, Nobuo OHGANE, Tsuyoshi NAKAMURA, Gosei ...1989 Volume 37 Issue 5 Pages 1337-1340
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA galactosaminoglycan (CO-N) obtained by ultrasonication from a protein-bound polysaccharide SN-C, which was isolated from Cordyceps ophioglossoides culture, has a direct cytotoxicity against tumor cells (Ohmori et al., Chem. Pharm. Bull., 37, 1019 (1989). High peformance liquid chromatographic analysis revealed that CO-N shows a broad molecular weight distribution with an average molecular weight of 33000. A potent antitumor activity of CO-N was observed in the higher-molecular-weight fraction on gel filtration, and the low-molecular-weight fraction below 6600 showed a weak activity. However, the depolymerized CO-N (ca. 5500) obtained by further ultrasonication of the original CO-N still retained the antitumor activity of CO-N against Ehrlich ascitic carcinoma or MM46 solid mammary carcinoma.View full abstractDownload PDF (632K) -
Hirokazu ADACHI, Kiyoshi KONISHI, Isamu HORIKOSHI1989 Volume 37 Issue 5 Pages 1341-1344
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe inhibitory effects of pure galloylglucose (1, 2, 3, 4, 6-penta-O-galloyl-β-D-glucose) on the respiratory chain of rat liver mitochondria were investigated. The respiratory control ratio (RCR) decreased by 50% on addition of 20 μM pentagalloylglucose to highly coupled mitochondria, but the adenosine-5'-diphosphate/oxygen (ADP/O) ratio decreased only slightly. The RCR disappeared and the ADP/O ratio could not be measured at concentrations of pentagalloyl-glucose above 30 μM. On the other hand, the uncoupler-induced oxygen consumption was also inhibited. These findings suggest that pentagalloylglucose at low concentrations inhibits the electron transport system to decrease the RCR, but scarcely impairs the membrane, practically retaining the coupled reaction, while at high concentrations it impairs the structural integrity of the mitochondrial membrane.Pentagalloylglucose competitively inhibited succinate dehydrogenase activity, and noncompetitively inhibited reduced nicotinamide adenine dinucleotide (NADH) dehydrogenase and ubiquinol-1 oxidase activities of submitochondrial particles (SMP). However, it did not show significant inhibition of the cytochrome c oxidase activity of SMP. It is thus concluded that pentagalloylglucose, which is the lowest-molecular-weight component of tannic acid, exerts its effect on mitochondrial respiration and oxidative phosphorylation through action on the membrane and on succinate dehydrogenase, NADH dehydrogenase and cytochrome bc1 complex of mitochondria.View full abstractDownload PDF (595K) -
Keiko KURODA, Mitsutaro AKAO1989 Volume 37 Issue 5 Pages 1345-1346
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFumaric acid (FA) suppressed the carcinogenesis in the liver of rats fed 3'-methyl-4-(dimethylamino)azobenzene (3'-Me-DAB), and a study was performed to examine the effect of FA on deoxyribonucleic acid (DNA) synthesis and subcellular structures of hepatocytes under the anticarcinogenic regimen. Male Donryu strain rats were given 3'-Me-DAB by being fed a diet containing 0.06% 3'-Me-DAB for 50 d. They were then given a diet containing 1% FA and drinking water containing 0.025% FA for 53 to 69 weeks. Hepatocytes were isolated from the liver by the collagenase perfusion method and placed in culture, and their activity for DNA synthesis was measured in terms of the incorporation of [3H]dThd into DNA. An enhanced DNA synthesis of hepatocytes was noted in the rats given FA, indicating that FA enhanced the proliferation of hepatocytes to counteract the carcinogenic effect of 3'-Me-DAB. An electron microscopic examination indicated that the distribution of subcellular organella was almost normal in the FA-treated hepatocytes.View full abstractDownload PDF (534K) -
Jun YATSUYANAGI, Sanae MURAOKA, Ryou TSUTSUI, Taketo OGISO1989 Volume 37 Issue 5 Pages 1347-1350
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe effect of Pb2+ on serum-treated zymosan (STZ)-induced O2 consumption of rat peritoneal neutrophils was studied. Pb2+ was found to mimic effectively the enhancing action of Ca2+ on the O2 consumption depending on the concentration up to about 80 μM. However, at concentrations over 80 μM, Pb2+ inhibited the O2 consumption. The enhancing effect of Pb2+ on the O2 consumption was further examined using the intracellularly Ca2+ -depleted neutrophils. Pb2+ also enhanced the O2 consumption of the Ca2+-depleted cells as effectively as Ca2+. The Pb2+-enhanced O2 consumption of the Ca2+-depleted cells was inhibited by N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide (W-7) based on its calmodulin antagonistic action. The effect of Pb2+ on the activity of activator-deficient 3', 5'-cyclic nucleotide phosphodiesterase (PDE), a calmodulin-dependent enzyme, was examined. Pb2+ activated PDE as effectively as Ca2+ only in the presence of calmodulin. The Pb2+-activated PDE activity was also inhibited by W-7 only in the presence of calmodulin. These results indicated that Pb2+ could replace Ca2+ in the activation process(es) of the respiratory burst, suggesting a possible involvement of calmodulin in the enhancing mechanism of the O2 consumption by Pb2+.View full abstractDownload PDF (710K) -
Rensuke GOTO, Hiroyuki KUBO, Shoji OKADA1989 Volume 37 Issue 5 Pages 1351-1354
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIn order to apply liposomes prepared from synthetic amphiphiles containing amino acid residues to radiopharmaceuticals, their labeling with 99Tc or 99mTc and stability in saline or in serum were investigated. These liposomes were highly labeled by embedding stearylamine-diethylenetriamine pentaacetic acid as a ligand of technetium. The labeling was more efficient at pH 7.0 than at pH 4.0 or 8.5. Among these technetium-labeled liposomes tested, liposomes containing the alanine residue were stable in saline or in 50% serum at 37°C for at least 24h, in contrast to liposomes (phosphatidylcholine : cholesterol=1 : 1 molar ratio) whose stability had been enhanced by adding cholesterol.View full abstractDownload PDF (690K) -
Shigeyuki ISHIKAWA, Masao KOBAYASHI, Masayoshi SAMEJIMA1989 Volume 37 Issue 5 Pages 1355-1361
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTo evaluate the influence of solid particles on the rheological properties of semisolids, 6 inorganic powders classified as follows were added to vaseline; 1) fine and rigid powders (ZnO, TiO2), 2) porous powders (hydrated silicon dioxide (Cp), synthetic aluminum silicate (SiAl)), and 3) lubricating powders (talc, magnesium stearate (StMg)). Rheological measurements were performed by the oscillation method and continuous shear method.As determined by the oscillation method, the profiles of storage modulus (G'), loss modulus (G''), and loss tangent (tan δ) vs. powder concentration (fp) varied from powder to powder. In group 1, log G's increased monotonously on addition of ZnO, whereas they were scarcely changed at low fp but increased gradually at high fp in the case of TiO2. This difference seemed to be caused by a difference in their affinity for vaseline. In group 2, log G's changed only a little at low fp but increased rapidly at higher fp. In group 3, StMg showed the characteristic effect that it reduced G' at fp values below 0.3.Most of the powders gave maximum values of tan δ at a powder volume fraction (φp) below 0.04, and these peaks were presumed to reflect the beginning of structure formation.As determined by the continuous shear method, porous powders (group 2) increased the apparent viscosity at high shear rate (η625) but the other powders did not increase η625 so much. This suggests that the structures formed by porous powders were resistant to shear but those formed by other powders were not.View full abstractDownload PDF (1213K) -
Hisakazu SUNADA, Itaru SHINOHARA, Akinobu OTSUKA, Yorinobu YONEZAWA1989 Volume 37 Issue 5 Pages 1362-1365
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe dissolution of sieved n-propyl p-hydroxybenzoate crystalline particles mixed at various weight ratios devised to give symmetrical particle size distributions was conducted under the sink condition. These dissolution processes were simulated on the basis of the change of surface area estimated for the component samples. The mixed ternary systems were converted into several imaginary symmetrical particle-size-distributed systems, and the dissolution processes of the original mixed systems were simulated with the imaginary systems by making use of the relationship between the surface-producing rate constant and the initial particle size. The validity of the simulation on the bases of the surface-producing rate constant and the introduction of imaginary particles was also examined. The simulated values showed fairly good coincidence with those measured. The values simulated by the use of the changes of surface area during the dissolution, obtained by graphical integration for the components, were closer to the measured values than those simulated by the use of the relationship between the surface-producing rate constant and the initial particle size. However, the latter simulation method was thought to be more useful than the former, because the surface area produced during the dissolution is given by a generalized function of the initial particle size and the dissolution behavior of mixed systems was predictable when the initial particle size of the components were defined in advance.View full abstractDownload PDF (565K) -
Kimiko SATOH, Kozo TAKAYAMA, Yoshiharu MACHIDA, Yoshiki SUZUKI, Masayu ...1989 Volume 37 Issue 5 Pages 1366-1368
Published: May 25, 1989
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe bioadhesive property of tablets consisting of hydroxypropyl cellulose (HPC) and carboxyvinyl polymer (CP) was investigated using the mouse peritoneal membrane. The adhesion force was significantly affected by the mixing ratio of HPC and CP in the tablet, and the weakest adhesion force was observed at the ratio of 3 : 2 (HPC : CP). Interpolymer complex formation was confirmed between HPC and CP in the acidic medium by turbidity and viscosity measurements. The interaction between CP carboxyl groups and HPC molecules was considered to be a possible mechanism for this complex formation on the basis of a Fourier-transform infrared spectroscopy. These observations suggested that the adhesion force of the HPC-CP tablet to the mucous membrane was significantly affected by the interpolymer complex formation between HPC and CP.View full abstractDownload PDF (551K)