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Volume 41, Issue 8
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Akihiro NOGUCHI, Shin-ichi KONDO, Masayuki KUZUYA1993 Volume 41 Issue 8 Pages 1331-1336
Published: August 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe conformational properties of bipyridine cardiotonics were investigated by means of quantum chemical (AM1(Austin Model 1)) calculations. The calculations for the tautomeric and ionic structures of 3, 4'-dipyridin-6(1H)-one (1), the basic structure for bipyridine cardiotonics, showed that the equilibrium conformations in the ionic structures are more planar than those in the neutral structures and that the rotational barrier of the cationic pyridone structure is characteristically higher compared to those of the pyridinol tautomer and 1'-hydro-3, 4'-bipyridinium cation. The difference in conformation between the well known cardiotonics, amrinone and milrinone, is more distinctive in the cationic structure, which is considered to be the usual structure in biological environments, than in the neutral structures.View full abstractDownload PDF (836K) -
Isao KITAGAWA, Kazuyuki HORI, Masahiro SAKAGAMI, Jun-Liang ZHOU, Masay ...1993 Volume 41 Issue 8 Pages 1337-1345
Published: August 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFollowing the characterization of licorice-saponins A3 (2), B2 (3), and C2 (4), the chemical structures of licorice-saponins D3 (5), E2 (6), F3 (7), G2 (8), H2 (9), J2 (10), and K2 (11), seven of the ten oleanane-type triterpene oligoglycosides isolated from the air-dried roots of Glycyrrhiza uralensis FISCHER collected in the northeastern part of China, were investigated. On the basis of chemical and physicochemical evidence, the structures of licorice-saponins D3, E2, F3, G2, H2, J2, and K2 have been determined to be expressed as 3β-[α-L-rhamnopyranosyl(1→2)-β-D-glucuronopyranosyl(1→2)-β-D-glucuronopyranosyloxy]-22β-acetoxyolean-12-en-30-oic acid (5), 3-O-[β-D-glucuronopyranosyl(1→2)-β-D-glucuronopyranosyl]glabrolide (6), 3-O-[α-L-rhamnopyranosyl(1→2)-β-D-glucuronopyranosyl-(1→2)-β-D-glucuronopyranosyl]-11-deoxoglabrolide (7), 24-hydroxyglycyrrhizin (8), 3-O-[β-D-glucuronopyranosyl-(1→2)-β-D-glucuronopyranosyl]liquiritic acid (9), 24-hydroxy-11-deoxoglycyrrhizin (10), and 3β-[β-D-glucuronopyranosyl(1→2)-β-D-glucuronopyranosyloxy]-24-hydroxyoleana-11, 13(18)-dien-30-oic acid (11), respectively.View full abstractDownload PDF (1309K) -
Yasuhiro TEZUKA, Yasushi YOSHIDA, Tohru KIKUCHI, Guo-Jun XU1993 Volume 41 Issue 8 Pages 1346-1349
Published: August 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSConstituents of Ephemerantha fimbriata (BL.) P. F. HUNT et SUMMERH, which is used as a source plant of the Chinese crude drug "Shi-Hu", were examined and two new phenanthrenes, fimbriol-A (2) and fimbriol-B (8), a new dihydrophenanthrene, ephemeranthol-C (6), and dihydroconiferyl dihydro-p-coumarate (5) were isolated together with denbinobin (1), (+)-pinoresinol (3), (+)-syringaresinol (4), 3, 4, 5-trimethoxybenzoic acid (7), lusianthridin (9), and dihydro-p-coumaric acid (10). Structures of the new compounds were elucidated by the use of spectroscopic methods including two-dimensional NMR techniques.View full abstractDownload PDF (584K) -
Isao KITAGAWA, Kazuyuki HORI, Masahiro SAKAGAMI, Fumi HASHIUCHI, Masay ...1993 Volume 41 Issue 8 Pages 1350-1357
Published: August 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo sweet oleanane-type triterpene oligoglycosides named apioglycyrrhizin and araboglycyrrhizin were isolated from the air-dried roots of Glycyrrhiza inflata BATALIN, collected in Xinjiang province (Shinkyo-Kanzo in Japanese), together with glycyrrhizin (3), licorice-saponins A3 (8), G2 (10), and H2 (11) and known flavonoid glycosides. On the basis of chemical and physicochemical evidence, the structures of apioglycyrrhizin and araboglycyrrhizin have been determined to be expressed as 3-O-[β-D-apiofuranosyl(1→2)-β-D-glucuronopyranosyl]glycyrrhetic acid (1) and 3-O-[α-L-arabinopyranosyl(1→2)-β-D-glucuronopyranosyl]glycyrrhetic acid (2), respectively.During the course of these studies, it has been found that the hydroxyl groups in the oligosaccharide moiety of the glucuronide saponins may be partially methylated by prolonged treatment with diazomethane in methanol. The sweetness of the saponins hitherto isolated from various Glycyrrhizae Radix has been examined and a structure-sweetness relationship, as compared with glycyrrhizin, has been found.View full abstractDownload PDF (1259K) -
Susumi HATAYAMA, Noriko OCHI, Seiichi TAKANO1993 Volume 41 Issue 8 Pages 1358-1361
Published: August 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS4-Methoxyl-6-[(1S)-1-(trimethylsilyloxy)-1-methyl-2-oxobutyl]-3, 5-dimethyl-2H-pyran-2-one (4), a key α-pyrone subunit for the synthesis of verrucosidin (1), has been prepared from 6-ethyl-4-hydroxy-3, 5-dimethyl-2H-pyran-2-one (5) in an enantiomerically pure form.View full abstractDownload PDF (723K) -
Tozo FUJII, Masashi OHBA, Hitoshi KAWAMURA, Tsuyoshi HANEISHI, Satoshi ...1993 Volume 41 Issue 8 Pages 1362-1365
Published: August 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS(1'S)-1-Methyl-cis-zeatin [(1'S)-2] and its 9-β-D-ribofuranoside [(1"S)-4] were synthesized from L-alanine through [S-(Z)]-4-amino-2-methyl-2-penten-1-ol ethanedioate [(S)-3]. Condensations of 2-hydroxy-6-methylthiopurine (16) with the trans-isomeric amine salt [(S)-15], its enantiomer [(R)-15], and the racemic modification [(±)-15] furnished (1'S)-, (1'R)-, and (±)-2-hydroxy-1'-methyl-trans-zeatine (6), respectively. A similar condensation of 16 with methylamine yielded 2-hydroxy-N6-methyladenine (7). These adenine derivatives were tested for cytokinin activity in the tobacco callus bioassay, and the order of their activity was (1'R)-6>(±)-6>(1'S)-2>7; on the other hand, (1"S)-4 and (1'S)-6 were completely inactive at 0.1-100μM and 0.01-10μM concentrations, respectively. As a result of the above syntheses of (1'R)-6, (1'S)-6, (±)-6, and 7, the gross structures of a marine green alga cytokinin and of a blue coral cytokinin were established to be 6 and 7, respectively.View full abstractDownload PDF (794K) -
Naoki NODA, Ryuichiro TANAKA, Masatoshi NISHI, Shoji INOUE, Kazumoto M ...1993 Volume 41 Issue 8 Pages 1366-1368
Published: August 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSNine lyso glycerophospholipids were isolated in the pure state from the crude drug "Suitetsu", which is the dried body of the leech, Hirudo nipponica (Hirudidae). They were identified as 1-O-hexadecyl-(1), 1-O-octadecyl-(2), 1-O-tetradecyl-(3), 1-O-9-cis-hexadecenyl-(4), 1-O-hexadecanoyl-(5), 1-O-pentadecyl-(6), 1-O-15-methylhexadecyl-(7), 1-O-octadecanoyl-(8) and 1-O-heptadecyl-sn-glycero-3-phosphocholine (9). Two of them (5 and 8) are lysophos-phatidylcholines and the other seven are lyso platelet-activating factors. One of them has an alkenyl carbon chain.View full abstractDownload PDF (528K) -
Mitsuya SAKURAI, Machiko SUGANO, Hiroshi HANDA, Tomoaki KOMAI, Ryuichi ...1993 Volume 41 Issue 8 Pages 1369-1377
Published: August 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSInhibitors of the protease of human immunodeficiency virus type-1 (HIV-1) were designed and synthesized. A reduced peptide, simple aminoalcohol, and statine analog, 4-amino-3-hydroxy-5-phenylpentanoic acid (AHPPA), were inserted at the scissile site of substrate sequences of HIV-1 protease. While both reduced peptides and simple aminoalcohol derivatives were weak inhibitors, the peptides containing AHPPA demonstrated moderate inhibitory activity. The more potent alcohol configuration of AHPPA is (R), which is opposite to the configuration in potent inhibitors of other aspartic proteases. In particular, compound 28 ((3R, 4S)-4-(N-tert-butoxycarbonyl-L-glutaminyl-L-asparaginyl)amino-3-hydroxy-5-phenylpentanoic acid 2'-methylbutylamide) had a Ki of 0.36μM and exhibited excellent enzyme specificity.View full abstractDownload PDF (1496K) -
Mitsuya SAKURAI, Susumu HIGASHIDA, Machiko SUGANO, Takahide NISHI, Fuj ...1993 Volume 41 Issue 8 Pages 1378-1386
Published: August 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSHuman immunodeficiency virus type 1 (HIV-1) protease inhibitors containing four types of hydroxyethylene dipeptide isosteres were designed and synthesized. These inhibitors consist of eight stereoisomers of phenylalanylproline (Phe-ψ[H.E.]-Pro), four stereoisomers of phenylalanylalanine (Phe-ψ[H.E.]-Ala), and one stereoisomer each of phenylalanylglycine (Phe-ψ[H.E.]-Gly) and cyclohexylalanylalanine (Che-ψ[H.E.]-Ala) hydroxyethylene dipeptide isosteres. For the synthesis of the latter two isosteres, a newly developed synthetic method for γ-lactone was applied. The inhibitory activities of these peptides were evaluated by cleavage assay of partially purified gag proteins or purified synthetic peptide. Of the inhibitors examined, compounds 2c (Z-Asn-(2S, 3R, 4S, 5S)-Phe-ψ[H.E.]-Pro-NHBun; Bun=n-butyl, Ki=0.50μM), 21a (Z-Asn-(2R, 4S, 5S)-Phe-ψ[H.E.]-Ala-NHBun, Ki=0.34μM) and 23 (Z-Asn-(2R, 4S, 5S)-Cha-ψ[H.E.]-Ala-NHBun, Ki=0.46μM) were moderately potent inhibitors. The results revealed that the alkyl substituent at C2 is essential, and the stereochemistry of the hydroxyethylene dipeptide isosteres greatly affected their inhibitory activities.View full abstractDownload PDF (1379K) -
Hiroki UEDA, Tetsuyuki IKEDA, Hisao KAKEGAWA, Hideki MIYATAKA, Hitoshi ...1993 Volume 41 Issue 8 Pages 1387-1390
Published: August 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA novel series of 4-guanidinomethylbenzoic acid (GMBA) arylamides was synthesized. Several showed more potent inhibitory effects on stress-induced gastric lesion in rats than cetraxate. We selected 4-guanidinomethylbenzoic acid (2'-ethoxycarbonyl)phenylamide 3 for further pharmacological assessments because it had low toxicity. Compound 3 showed significant inhibitory effects on stress-, HCl-ethanol- and indomethacin-induced gastric lesions and gastric secretion, the ED50 values being 34.4, 45.0 and 23.0mg/kg (p.o.) and 240mg/kg (i.d.), respectively. Furthermore, this compound restored the reduction of gastric mucus caused by the stress-loading and inhibited compound 48/80-induced ulcer.View full abstractDownload PDF (609K) -
Yusuke SASAKI, Akihiro AMBO, Kyoko MIDORIKAWA, Kenji SUZUKI1993 Volume 41 Issue 8 Pages 1391-1394
Published: August 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS[D-Ala2]Deltorphin II (DL-II) analogs having various aliphatic amino acids at positions 5 and 6 were synthesized by a solid-phase method and their opioid activites on electrically inducewd guinea pig ileum (GPI) and mouse vas deferens (MVD) preparations were determined. During the synthesis of an analog, [tert-leucine(Tle)5, 6]DL-II, we encountered difficulty in the coupling reaction between Tle5 and Tle6 with the usual diisopropylcarbodiimide (DIPCDI)-mediated tert-butoxycarbonyl (Boc) strategy, though the other analogs could be successfully synthesized. We found that the fluorenylmethoxycarbonyl (Fmoc)-Tle/DIPCDI/1-hydroxybenztriazole method was very useful for the synthesis of such a peptide having a sterically hindered sequence. Acid hydrolysis studies of the synthetic analogs suggested that the steric hindrance of consecutive aliphatic amino acid sequences depend upon the degree of branching at the β-carbon atom of the amino acids. In the MVD assay, two analogs, [Ala5, 6] and [Tle5, 6]DL-II showed remarkably low potencies while other analogs with Nva5, 6, Nle5, 6, Ile5, 6, Leu5, 6 and Mle5, 6 substituted for Val5, 6(DL-II) showed comparable or slightly lower potencies than DL-II. In the GPI assay, no remarkable changes in potency were observed between DL-II and this series of analogs. Conformational aspects of synthetic analogs were examined by comparing the circular dichroism spectra.View full abstractDownload PDF (733K) -
Setsuo SAITO, Jun EBASHI, Shigeya SUMITA, Takako FURUMOTO, Yoichi NAGA ...1993 Volume 41 Issue 8 Pages 1395-1401
Published: August 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSGlycosylations of 3-O-{2, 3, 4-tri-O-acetyl-α-L-rhamnopyranosyl(1→2)-3, 4-di-O-acetyl-α-L-arabinopyranosyl}-23-O-acetylhederagenin (15) with mono- (16), di- (17) and trisaccharide bromide (18) gave the bisdesmoside peracetates 19, 20 and 22, respectively, which were treated with 5% KOH in MeOH to give the bisdesmosides 25-27. Hydrolysis of the glycosides 6 and 9 having β-D-glucopyranose as a terminal sugar component with β-glucosidase in acetate buffer (pH 4.7) gave compounds 28 and 29, respectively. Cytoprotective effects of the synthesized triterpenoidal saponins against CCl4-induced hepatic injury were compared with those of saponins isolated from the leaves of Aralia elata SEEM. (Araliaceae) using isolated hepatocytes from rat liver. Although the monodesmosides 1-4 having neutral sugar components only at the O-3 position on the aglycones showed no cytoprotective effect, bisdesmosides having sugar components at both the O-3 and O-28 positions on the aglycones had potent effects, even when the species of the sugar components were different. The bisdesmosides 10, 11, and 27 having five monosaccharides in the molecules exhibited the most potent cytoprotective effects.View full abstractDownload PDF (984K) -
Hideji ITOKAWA, Kazuyuki KONDO, Yukio HITOTSUYANAGI, Megumi ISOMURA, K ...1993 Volume 41 Issue 8 Pages 1402-1410
Published: August 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA number of RA-VII derivatives having various amino acids including proline (6), pipecolic acid (11), norvaline (12), ornithine (14), aspartic acid (15) and methionine (20) in place of Ala2 have been synthesized from RA-X methyl ester (3) and evaluated for cytotoxicity to P388 leukemia and KB cells in vitro. Comparison of the cytotoxicity of these compounds suggests that the polarity and the length of the 2nd amino acid residue affect the activity. An NMR study revealed that, in solution, 6 and 11 are locked in one conformational state, corresponding to conformer A of RA-VII.View full abstractDownload PDF (1377K) -
Daikichi HORIGUCHI, Kiyoka MAEDA, Kazumi SASAMOTO, Yosuke OHKURA1993 Volume 41 Issue 8 Pages 1411-1414
Published: August 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new β-diketone-type ligand for Eu3+, N, N'-di(2-hydroxybenzyl)ethylenediamine-N, N'-bis(3-phenylpropane-1, 3-dione) was synthesized and the fluorescence property of its complex with Eu3+ was studied. The ligand was found to form a stable fluorescent complex with Eu3+ in an aqueous solution.View full abstractDownload PDF (632K) -
Xiao-drong TIAN, Zhi-da MIN, Ning XIE, Yan LEI, Zi-yue TIAN, Qi-tai ZH ...1993 Volume 41 Issue 8 Pages 1415-1417
Published: August 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTow novel abietane derivatives, cyrtophyllones A (1) and B (2), together with six known compounds, teuvincenone F (3), unicinatone (4), sugiol (5), friedelin (6), clerodolone (7), stigmasta-5, 22, 25-trien-3β-ol (8) and clerosterol (9), were isolated from the stem of Clerodendron cyrtophyllum. One of the abietane diterpenes, cyrtophyllone A, possesses a rearranged-abietane skeleton wich contains a 17(15-16)-abeo-abietane framework. The stereo-structure proposed for 1 was characterized as 16(S)-12, 16-epoxy-11, 14-dihydroxy-6-methoxy-17(15-16)-abeo-abieta-5, 8, 11, 13-tetraen-7-one on the basis of spectral analysis (UV, IR, MS, two dimensional (2D) NMR and CD) and X-ray diffraction. The structure of 2 was also characterized as (+)-11, 12, 16-trihydroxy-abieta-8, 11, 13-trien-7-one by a combination of spectroscopic comparison with sugiol.View full abstractDownload PDF (535K) -
Hiroshi MORITA, Kouji MATSUMOTO, Koichi TAKEYA, Hideji ITOKAWA, Yoichi ...1993 Volume 41 Issue 8 Pages 1418-1422
Published: August 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo novel tropoloisoquinoline alkaloids, Pareirubrines A and B, have been isolated as antileukemic substances from Cissampelos pareira(Menispermaceae), together with the same skeleton alkaloids, grandirubrine and isoimerubrine. Their structures were elucidated by nuclear magnetic resonance (NMR) studies, and their solid state tautomeric forms were examined by X-ray crystallographic analysis.View full abstractDownload PDF (699K) -
Kazumi DANJO, Kenji KAMIYA, Akinobu OTSUKA1993 Volume 41 Issue 8 Pages 1423-1427
Published: August 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSticking is a common phenomenon in the manufacture of tablets in which the top of a tablet becomes pilled during compression.The effects of tableting machine temperatures on the sticking of butyl-p-hydroxybenzoate were examined. Sticking was estimated by measuring the pressure placed on a scraper (scraper pressure, or SCR). The pressure reached a maximum value at a homologous temperature of around T/Tm=0.90, where the probability of sticking is high. It was found that sticking occurs easily in materials having a low melting point and in fine particles when compression stress and temperature are constant.We also found that the x^--R control charts obtained by measuring SCR help to detect sticking. Moreover, a shear test of tablets on a temperature-controlled metal plate was carried out, and the results were similar to those of the SCR; that is, the shear strength (C) and friction coefficient (μ) reached a maximum value at T/Tm=0.90.View full abstractDownload PDF (680K) -
Eijiro HORISAWA, Akio KOMURA, Kazumi DANJO, Akinobu OTSUKA1993 Volume 41 Issue 8 Pages 1428-1433
Published: August 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe effect of the physicochemical properties of binders on the strength of agglomerates prepared by the wet method was investigated using untreated and surface trimethylsilylated glass beads as model powders. The crushing test of granules and the bending test of molded tablets were carried out in order to estimate the strength of the agglomerates. A quantitative approach based on the work of Rumpf et al. was attempted to obtain the strengths between two contacting particles. The calculated values were in fair agreement with those obtained by the separation test using two big balls. In all the systems, the agglomerates prepared from surface treated glass were weaker in strength than those from untreated glass. In conclusion, it was apparent that the strength of an agglomerate was related both to the wetting of a particle by a binder solution and to the binder cohesion.View full abstractDownload PDF (813K) -
Yoshikazu TAKEUCHI, Hidehito YASUKAWA, Yumiko YAMAOKA, Naoki TAKAHASHI ...1993 Volume 41 Issue 8 Pages 1434-1437
Published: August 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFourie transform infrared/attenuated total reflection analysis demonstrated that the absorbance intensity of C=O stretching bands, which reflect the amounts of lipids in the stratum corneum, decreased with an increase in the duration of skin treatment with 0.15M oleic acid/propylene glycol (PG) system, suggesting that the oleic acid/PG system induced the lipid extraction, which was followed by a reorganization of the stratum corneum structures. The spectral peaks which originated from the PG molecule were detected in dermal tissues after 30 min of treatment of the stratum corneum with the same system. This observation suggested that the reorganization of the lipid domains due to the lipid extraction by the oleic acid/PG system helped the PG molecules enter the dermal tissues. It was also suggested that an effective volume within the stratum corneum for solutes and/or solvents which could penetrate through the inter-, and/or intracellular routes could be altered in conjunction with the structural changes of the lipids.View full abstractDownload PDF (712K) -
Shigeru AOKI, Hidenobu ANDO, Ryoichi MACHIDA, Katsumi IDA, Sumio WATAN ...1993 Volume 41 Issue 8 Pages 1438-1443
Published: August 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe effect of formulation variables on the release rate of phenylpropanolamine hydrochloride (PPA) from hydroxypropylcellulose (HPC)-ethylcellulose (EC) complex was investigated. With an increase in the weight fraction of HPC (WFH) in the filler, drug release from the solid made from a dissolved mixture of HPC and EC (SMH) tended to decrease. The major controlling factors appeared to be WFH in the filler, the HPC viscosity grade, and the PPA : filler ratio. When a low viscosity grade of HPC (HPC-L) was used, the release rates from the SMH matrix were greater than those from the physically mixed matrix at less than 50% WFH. EC particles obtained from SMH after a 6-hour dissolution test possessed a number of pores. It was assumed that after dissolving HPC-L from the SMH filler, the porous EC particles might promote drug release because the number of water channels increased. Variation in the compression pressure in the tablet manufacturing process was an insignificant factor in the drug release rate. A linear relationship was observed between the release rate and the reciprocal amount of filler. Furthermore the release rate as a function of surface area of the tablet was also in good relationship. With these relationships, the composition of the tablet can be predicted to obtain the demand release rate of the drug.View full abstractDownload PDF (1132K) -
Masahiko SUZUKI, Kiyoko ITO, Chigusa FUSHIMI, Tamotsu KONDO1993 Volume 41 Issue 8 Pages 1444-1447
Published: August 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe freezing point depression method for studying drug interaction has been extended to a system containing both 1 : 1 (AB) and 1 : 2 (AB2) complexes. The osmotic concentration of dilute aqueous solutions was measured by this method with a commercially available osmometer. On the basis of the colligative properties, a mathematical model has been proposed to calculate the apparent stability constants (K1 and K2). This method is applied to complexes of α-cyclodextrin with three barbiturate derivatives (barbital, phenobarbital, and pentobarbital). The results showed that the apparent stability constants obtained were in fair agreement with those obtained by the spectroscopic method. The advantage of this method is that the apparent stability constant could be estimated quickly using a simple procedure.View full abstractDownload PDF (554K) -
Hajime MATSUDA, Kenzo ITO, Yoshiko SATO, Daisuke YOSHIZAWA, Muneo TANA ...1993 Volume 41 Issue 8 Pages 1448-1452
Published: August 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTo obtain a transparent and effective solution of p-hydroxybenzoic acid esters (parabens), the use of 2-hydroxypropyl-β-cyclodextrins (2-HP-β-CyDs) as solubilizers with different degrees of substitution (D.S.) was surveyed. 2-HP-β-CyDs significantly increased the aqueous solubility of four kinds of parabens (methyl<ethyl<propyl<butyl esters), where the solubilizing ability decreased with an increase in the D.S. of the 2-hydroxypropyl group in β-CyD. The antimicrobial activity of the parabens tended to decrease by complexation with 2-HP-β-CyDs. However, the activity could be maintained by lengthening the alkyl chain of the parabens. 1H-and 13C-nuclear magnetic resonance and circular dichroism spectroscopic studies suggest that the hydrophobic alkyl moiety of butyl paraben is preferably included in the cavity, and the phenol group extrudes from the cavity. The present results suggest that a suitable combination of 2-HP-β-CyDs and hydrophobic, longer alkyl parabens is useful for the preservation of liquid formulations.View full abstractDownload PDF (772K) -
Shoko YOKOYAMA, Masaaki SUNOHARA, Tadao FUJIE1993 Volume 41 Issue 8 Pages 1453-1455
Published: August 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSNew crystalline complexes composed of fatty acids (FA) and 3-aminopyridine (3AP), FA-3AP, were prepared, and the physicochemical properties of FA-3AP were investigated by elemental analysis, differential scanning calorimetry and infrared (IR) spectroscopy and compared with those of FA-nicotinamide (NAA) complexes, FA-NAA.The molar ratio of 3AP to FA in the FA-3AP was 1 : 1, the same as FA-NAA. The melting points of FA-3AP were lower than that of the corresponding FA-NAA and FA alone. The relationship between the melting points of FA-3AP and the carbon number (n) of the constituent FA took a linear form as shown in FA-NAA, whereas the relationship between the melting points of FA and n took a zig-zag one. In the IR spectrum, the absorption band near 1700cm-1 which is the characteristic of the carbonyl stretching vibration was shifted to higher frequency fields by the formation of FA-3AP as observed for FA-NAA. The binding of 3AP to FA seemed to be similar to that of NAA.View full abstractDownload PDF (482K) -
Yun-Lian LIN, Yueh-Hsiung KUO1993 Volume 41 Issue 8 Pages 1456-1458
Published: August 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new dehydrorotenoid, 6a, 12a-dehydro-β-toxicarol, and a new pterocarpan, derricarpin, together with a known compound, 6a, 12a-dehydro-α-toxicarol, have been isolated from the roots of Derris oblonga. Their structures were determined on the basis of spectral and chemical evidence.View full abstractDownload PDF (486K) -
Takashi MATSUMOTO, Yoshio TAKEDA, Hiromitsu TERAO, Tomoko TAKAHASHI, M ...1993 Volume 41 Issue 8 Pages 1459-1461
Published: August 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe acetate (11), propanoate (12), butanoate (13), 2-methylpropanoate (14), hexanoate (15), decanoate (16), and hexadecanoate (17) of (±)-2-(p-tolyl)-1-propanol (2) were predominantly hydrolyzed with lipase to give (S)-(-)-2-(p-tolyl)-1-propanol (2). However, the 2, 2-dimethylpropanoate (18), benzoate (19), and phenylacetate (20) of (±)-2 were recovered intact even when the reaction was carried out for 100h. From the viewpoints of enentioselectivity and reaction rate, the racemic ester 11 was found to be the most suitable substrate for the optical resolution of (±)-2.View full abstractDownload PDF (611K) -
Takashi MICHIDA, Yukako KASUYA, Hiroteru SAYO1993 Volume 41 Issue 8 Pages 1462-1464
Published: August 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA P-450 model system consisting of metallo-meso-tetraphenylporphyrins, O2 and NaBH4 in basic solution is described. It has three remarkable features; 1) dioxygen is activated on a metalloporphyrin; 2) the reductant is used effectively, i.e., the efficiency of the reductant, calculated on the assumption that two electrons are consumed to produce an active-two-electron oxidant in the catalytic cycle, is 37%; 3) the life of the catalyst is extremely long for a P-450 model system. The maximum turnover is 336.When meso-tetraphenylporphyrinatomanganese(III) chloride (1) was used as a catalyst in this system, diphenyl sulfide was oxidized stepwise to diphenyl sulfoxide an then to diphenylsulfone. When meso-tetraphenylporphyrinatoiron(III) chloride (2) was used as a catalyst, diphenyl sulfide was oxidized quantitatively to diphenyl sulfoxide.View full abstractDownload PDF (529K) -
Takeshi SANO, Kiyoshi IKEDA, Kazuo ACHIWA1993 Volume 41 Issue 8 Pages 1465-1468
Published: August 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new methodology for chemical differentiation of one amino and four hydroxyl groups of D-galactosamine derivatives and its application for the synthesis of D-galactosamine-4-phosphate analogs of lipid A are described. Preliminary examination of biological activity revealed that the synthetic monosaccharides show mitogenic activity.View full abstractDownload PDF (676K) -
Mineo SHIMIZU, Yutaka ZENKO, Ryoichi TANAKA, Tomoko MATSUZAWA, Naokata ...1993 Volume 41 Issue 8 Pages 1469-1471
Published: August 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAldose reductase (AR) inhibitory activity-directed fractionation of Hachimi-jio-gan has led to the isolation of 5-(hydroxymethyl)-2-furfuraldehyde (1) and ellagic acid (2). 2 was reported to be a strong AR inhibitor in this series of study on AR inhibitors, but 1 is the first isolation from a natural source and as an AR inhibitor. The AR inhibitory activity of the eight crude drugs which constitute Hachimi-jio-gan, and a comparison of their components by TLC, were also examined. Corni Fructus was found to be one of the important drugs having an AR inhibitory effect, and only in this drug were compounds 1 and 2 contained together.View full abstractDownload PDF (449K) -
Munehisa ARISAWA, Takahiro HORIUCHI, Toshimitsu HAYASHI, Yasuhiro TEZU ...1993 Volume 41 Issue 8 Pages 1472-1474
Published: August 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new glycoside, evodioside B (1) was isolated from the n-BuOH-soluble fraction of the MeOH extract of the leaves of Evodia rutaecarpa (JUSS). BENTH. (Rutaceae) together with rutin and hyperin. Epimedoside C (2), hyperin, and guaijaverin were isolated from the EtOAc-soluble fraction and dehydroevodiamine·hydrogenchloride (3) was isolated from the CHCl3-soluble fraction as were limonin and β-sitosterol. The structure of compound 1 was determined to be 5, 7, 4'-trihydroxy-8-isopentenylflavanone 7, 4'-di-O-β-D-glucopyranoside on the basis of spectroscopic evidence, and the 1H- and 13C-NMR signals of 2 and 3 were completely assigned.View full abstractDownload PDF (647K) -
Hisao TOMIDA, Chikara MIZUO, Chie NAKAMURA, Setsuo KIRYU1993 Volume 41 Issue 8 Pages 1475-1477
Published: August 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSCa-alginate gel beads loaded with a model cationic drug imipramine were prepared, and their drug release characteristics were examiend. By soaking plain Ca-alginate gel beads in an imipramine solution, the slightly translucent beads were transformed into white beads, seemingly due to the precipitation of a drug-alginate complex. The amount of drug uptake in the beads increased linearly as the initial drug concentration increased (1-10mg/ml). However, no significant difference in uptake efficiency was observed between the beads prepared over various periods of curing time. The drug release rate from the beads was in the following order : JP XII disintegration test solution No. 1 (pH 1.2)>0.9% (w/v) NaCl≒test solution No. 2 (pH 6.8)>distilled water. The release rates were also measured in HCl solutions, NaCl solutions, and acetate buffers with varying pHs. It was suggested that imipramine ions interacting with the acidic residues of alginates were replaced by cations in the release medium and diffused out of the beads. Therefore, Ca-alginate gel could be a useful vehicle for the controlled release of water-soluble cationic drugs.View full abstractDownload PDF (525K) -
Hiroshi MORITA, Kouji MATSUMOTO, Koichi TAKEYA, Hideji ITOKAWA1993 Volume 41 Issue 8 Pages 1478-1480
Published: August 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSConformational analysis of antileukemic tropoloisoquinoline alkaloids isolated from Cissampelos pareira was conducted by thermodynamic proton nuclear magnetic resonance (1H NMR) studies. The line-broadening of one of methoxy methyl signals can be explained by the tropolone ring-puckering process. Analysis by dynamical simulated annealing and modified neglect of differential overlap (MNDO) calculations also supported puckering of tropolone ring system.View full abstractDownload PDF (428K) -
Toshio SUZUKI, Hitoshi TADA, Yasuyuki MATSUDA, Xiao-hong YANG, Katsuo ...1993 Volume 41 Issue 8 Pages 1481-1483
Published: August 15, 1993
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSKinetic examination for methoxycarbonylations of the isomeric steroid-17-yl methyl glycolates at C-20 and plots of the amount of each isomer produced by a reaction of their corresponding steroids with cupric acetate in absolute methanol provide a general and facile method for determination of the configuration of the steroid-17-yl methyl glycolates at C-20.View full abstractDownload PDF (476K)
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