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Volume 43, Issue 10
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Takeo INOHARA, Mariko TARUI, Yoshitetsu MIHARA, Mitsunobu DOI, Toshima ...1995 Volume 43 Issue 10 Pages 1607-1613
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe compounds, 3-amino-1, 4-dimethyl-5H-pyrido[4, 3-b]indole(Trp-P-1) and 3-amino-1-methyl-5H-pyrido[4, 3-b]indole (Trp-P-2), are major potent mutacarcinogens isolated from tryptophan pyrolysate. In order to investigate their interaction with DNA and effects on DNA conformation, studies involving circular dichroism, fluorescence and absorption spectroscopy and viscometric titration were performed. The results show that (a) Trp-P-1 and Trp-P-2 are potent intercalators of DNA with nearly the same specificity for the A-T and G-C (alternative purine-pyrimidine) base sequences, (b) the interaction of Trp-P-1 with the B-form of DNA is biphasic so that stiffening of the B-DNA conformation occurs over the range r ([Trp-P-1]/[DNA])=0-2.5, followed by transformation of B to the non-B conformation at r>2.5, (c) the transformation to the non-B structure is not observed for Trp-P-2, although stiffening of the B-DNA conformation similarly occurs, and (d) both Trp-P-1 and Trp-P-2 promote unwinding of the salt-induced Z-DNA to give the B-form. These data indicate that the noncovalent interaction of Trp-P with DNA is mainly dependent on the B-form conformation.View full abstractDownload PDF (921K) -
Yuki KOMATSU, Norio MINAMI1995 Volume 43 Issue 10 Pages 1614-1616
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSynthesis of a novel dual inhibitor of thromboxane A2 synthetase and 5-lipoxygenase, 5, 7-dimethyl-6-hydroxy-2-methylamino-4-(3-pyridylmethyl)benzothiazole (E3040), was accomplished via a new coupling reaction, in which a key intermediate, (3, 6-dihydroxy-2, 4-dimethylphenyl)-(3-pyridyl)methanol, was easily synthesized in a high yield from 2, 6-dimethyl-1, 4-benzohydroquinone and 3-pyridinecarboxaldehyde in 6N hydrochloric acid. The regio isomers of 3-pyridinecarboxaldehyde also gave the corresponding coupling products in high yields.View full abstractDownload PDF (596K) -
Shigeyuki YOSHIFUJI, Mamoru KANAME1995 Volume 43 Issue 10 Pages 1617-1620
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSLycoperdic acid [(2S, 5'S)-2-amino-3-(5'-carboxy-2'-oxo-5'-tetrahydrofuranyl)propanoic acid], isolated from the mushroom Lycoperdon perlatum, was synthesized from trans-4-hydroxy-L-proline by a six-step route involving samarium diiodide (SmI2)-mediated formation of the spiro-γ-lactone and ruthenium tetroxide (RuO4) oxidation of the L-proline ring system to the L-pyroglutamic acid moiety. Lycoperdic acid (1) was found to undergo hydrolysis of the γ-lactone ring in 1 N hydrochloric acid at 23°C, giving an equilibrated mixture of 1 and the corresponding hydroxy acid.View full abstractDownload PDF (743K) -
Masashi KOTERA, Keitaro ISHII, Masanori SAKAMOTO1995 Volume 43 Issue 10 Pages 1621-1628
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSPhotocyclization reactions (γ=254nm) of γ-methyl δ-(4-hydroxybutyl) and δ-(-4-hydroxypentyl) α, β-unsaturated γ, δ-epoxy nitriles gave spiroketals and spirothers diastereoselectively, whereas reaction of δ-(6-hydroxyhexyl) nitrile allorded no cyclization product. In addition, photocyclization of nitrile bearing a carboxyl group in the δ-side-chain afforded spirolactone.View full abstractDownload PDF (1227K) -
Tsutomu HATANO, Li HAN, Shoko TANIGUCHI, Tetsuro SHINGU, Takuo OKUDA, ...1995 Volume 43 Issue 10 Pages 1629-1633
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTow new tannins, camelliatannins C (1) and E (2), were isolated from the leaves of Camellia japonica L. (Theaceae). They were found to be complex tannins of a new type, lacking C-C bond between glucose C-1 and the aroyl (hyxahydroxydiphenoyl) group at glucose O-2.View full abstractDownload PDF (796K) -
Kenji SHIOJIMA, Kazuo MASUDA, Hideki SUZUKI, Tokuhide LIN, Yuko OOISHI ...1995 Volume 43 Issue 10 Pages 1634-1639
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSForty-two triterpenoids including eight novel compounds, gammacer-16-en-3β-yl acetate (1), gammacer-16-en-3β-ol (2), gammacer-16-en-3α-ol (3), gammacer-16-en-3-one (4), pichierenyl acetate (5), pichierenone (6), isopichierenyl acetate (7) and isopichierenol (8), were isolated from the fresh roots of Picris hieracioides subsp. japonica, Compositae, and their structures were elucidated by means of spectroscopic analysis, and chemical correlations. Fifteen compounds were also obtained from the fresh aerial parts.View full abstractDownload PDF (899K) -
Kenji SHIOJIMA, Hideki SUZUKI, Hiroyuki AGETA1995 Volume 43 Issue 10 Pages 1640-1642
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThree new triterpenoids, olean-12-ene-2β, 3β, 22α-triol (1), urs-12-ene-2β, 3β, 22α-triol (2), urs-12-ene-2β, 3β, 28-triol (3), and a known one, olean-12-ene-2β, 3β, 28-triol (4), were isolated from the fresh roots of Picris hieracioides subsp. japonica, and their structures were elucidated on the basis of spectral data.View full abstractDownload PDF (523K) -
Keizo MATSUO, Masayo SUNAGO, Natsue OKUTANI, Tatsuko TAKAGI, Hiromi NA ...1995 Volume 43 Issue 10 Pages 1643-1646
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSHeating of 3-(2-aminophenylthio)-2-methoxycarbonyl-4-methyl-2-penten-4-olide with triethylamine hydrochloride gave 3, 3-dimethyl-1H, 3H-furo[4, 3-b][1, 5]benzothiazepin-1-one. Some chemical modifications of the product including [2+2]cycloaddition and 1, 3-dipolar cycloaddition to the imino group in the product were performed.View full abstractDownload PDF (711K) -
Masayuki YOSHIKAWA, Yoshihiro YOKOKAWA, Yasuhiro OKUNO, Nobuhiro YAGI, ...1995 Volume 43 Issue 10 Pages 1647-1653
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSNine myriocin analogs, 2-epi-myriocin, 14-deoxomyriocin, Z-14-deoxomyriocin, and nor-deoxomyriocins, were synthesized from 2-deoxy-D-glucose via common intermediates used in previous myriocin and Z-myriocin syntheses. Immunosuppressive activites of those myriocin analogs on mouse allogeneic mixed lymphocyte reaction were examined, and Z-14-deoxomyriocin was found to show the most potent activity among them. The structure-activity relationships are discussed.View full abstractDownload PDF (1115K) -
Xue-Long SUN, Toshitsugu KAI, Makoto TANAKA, Hiroaki TAKAYANAGI, Kimio ...1995 Volume 43 Issue 10 Pages 1654-1658
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe title compounds were synthesized from 3-deoxy-D-glycero-D-galacto-2-nonulosonic acid (5, KDN) by a new method which is similar to the Ritter reaction. The structures on these compounds were elucidated from the MS, elemental analysis, 1H-NMR and 13C-NMR, data, and the stereochemistry of methyl 4-benzoylamino-5, 7, 8, 9-tetra-O-acetyl-2, 6-anhydro-2, 3-dideoxy-D-glycero-D-galacto-non-2-enonate (13) was determined by X-ray crystallographic analysis.View full abstractDownload PDF (780K) -
Vladimir KHLEBNIKOV, Kenji MORI, Kohji TERASHIMA, Yuji TANAKA, Makoto ...1995 Volume 43 Issue 10 Pages 1659-1662
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAn enzymatic method for preparation of the enantiomers of chiral diols 2a, b and their monoacetates 3a, b with 100% enantiomeric purity by using lipase-catalyzed esterification and/or hydrolysis was established, The (R)-enantiomers were more reactive in both acetylation of (±)-2a, b and hydrolysis of (±)-3a, b catalyzed by lipase OF-360 from Candida cylindracea.View full abstractDownload PDF (755K) -
Qing HUANG, Yasuhiro TEZUKA, Yasumaru HATANAKA, Tohru KIKUCHI, Arasuke ...1995 Volume 43 Issue 10 Pages 1663-1667
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThree minor peptaibols, trichokonins (TKs)-Ia, Ib, and IX, were obtained from the culture broth of Trichoderma koningii OUDEMANS. Primary structures of these peptaibols were elucidated by ion-spray ionization mass spectrometry (ISI-MS) including the collision-induced dissociation (CID) technique together with two-dimensional nuclear Overhauser enhancement spectroscopy (NOESY).View full abstractDownload PDF (664K) -
Yoshio TAKEUCHI, Hidefumi IWASHITA, Kohji YAMADA, Mayumi GOTAISHI, Nor ...1995 Volume 43 Issue 10 Pages 1668-1673
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIn order to develop efficient chiral derivatizing agents (CDAs) which can be obtained readily in optically active form, synthetic studies of α-cyano-α-fluorophenylacetic acid (CFPA) analogs, 3a-e and CFNA (14a), were made. Carboxylation of 6a-e obtained from 4a-e gave 3a-e in low yield. Alternatively, benzyl cyanides 5b-e were converted successfully to the esters 7b-e, 8b-e, and 9b-e, which were fluorinated with FClO3 to produce the fluoro esters 10b-e, 11b-e, and 12b-d, in good yields. However, the attempted ester cleavage of these compounds did not give 3b-e. Carboxyl group introduction into 5e afforded 13, and fluorination with either F2 or FClO3 gave complex mixtures.Carboxylation of the naphthyl analog 16 obtained from 15 did not give 14a. However, fluorination of 18 derived from 17 proceeded readily to give 19, which was hydrolyzed to produce 14a. Optically active (-)-14a was obtained through enzymatic hydrolysis. The racemic acid 14a was condensed with three representative chiral nucleophiles to give 14b-d. From the 1H- and 19F-NMR spectra of these derivatives, it was concluded that CFNA (14a) is potentially a much better CDA than the well known α-methoxy-α-(trifluoromethyl)phenylacetic acid (MTPA).View full abstractDownload PDF (961K) -
Masahiro NAGAI, Junko DOHI, Motohiko MORIHARA, Nobuko SAKURAI1995 Volume 43 Issue 10 Pages 1674-1677
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFrom the stems of Myrica gale var. tomentosa (Myricaceae), two new diarylhyptanoids (3 and 4) were isolated together with myricanone, porson, gallic acid and myricetin 3-O-(6"-galloyl)-β-D-galactopyranoside. On the basis of spectroscopic and chemical evidence, the structures of 3 and 4 have been determined as 12-dehydroporson and 12-hydroxymyricanone, respectively. The structure of porson was reinvestigated, and a revised structure, 12-hydroxy-5-O-methylmyricanone, was proposed.View full abstractDownload PDF (743K) -
Koichi TSUJI, Hidetsugu TSUBOUCHI, Hiroshi ISHIKAWA1995 Volume 43 Issue 10 Pages 1678-1682
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA series of optically active substituted 1, 2-dihydro-6-oxo-pyrrolo[3, 2, 1-ij]quinoline-5-carboxylic acids was prepared via optically active 2-methyl-4, 5-difluoroindoline (10) and tested for antibacterial activities. Among them, (2S)-9-[(3R, 1'S)-3-(1'-amino)ethyl-1-pyrrolidinyl]-8-fluoro-1, 2-dihydro-2-methyl-6-oxo-6H-pyrrolo[3, 2, 1, -ij]-quinoline-5-carboxylic acid (19) showed potent activity against gram-positive bacteria and (2S)-8-fluoro-1, 2-dihydro-2-methyl-9-(3-methyl-1-piperazinyl)-6-oxo-6H-pyrrolo[3, 2, 1-ij]quinoline-5-carboxylic acid (16) exhibited well balanced in vitro activity, good intravenous efficacy, and high aqueous solubility.View full abstractDownload PDF (786K) -
Toru OKAYAMA, Sumie SEKI, Hajime ITO, Tomoko TAKESHIMA, Masaki HAGIWAR ...1995 Volume 43 Issue 10 Pages 1683-1691
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThree new lactam-conformationally restricted arginine derivatives, 1-butyl-3-(6, 7-dimethoxy-2-naphthylsulfonyl)-3-(3-guanidinoropyl)-substituted γ-, δ-, and ε-lactams (2-4), were synthesized on the basis of backbone modification of the lead structure, 6, 7-dimethoxy-2-naphthylsulfonylarginine n-butylmethylamide (1). We tested these compounds for inhibitory activity toward thrombin and other trypsin-like enzymes (trypsin, factor Xa, plasmin, and kallikrein). All the compounds synthesized (1-4) potently inhibited thrombin with IC50 values of 0.75, 0.70, 0.92, and 3.2μM, respectively; they inhibited thrombin over 40-fold more effectively than the other enzymes tested. The γ-lactam (2) with the most profound inhibitory activity toward thrombin was a reversible inhibitor with a Ki of 0.26μM. Compound 2 also showed better thrombin selectivity than the lead compound (1). The lactam-conformational restriction of arylsulfonylarginine amides, especially γ-lactam, has thus proved to be a useful device for the improvement of antithrombotic activity.View full abstractDownload PDF (1570K) -
Shoji KAMIYA, Hiroshi MATSUI, Hiroaki SHIRAHASE, Shohei NAKAMURA, Kats ...1995 Volume 43 Issue 10 Pages 1692-1695
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA novel series of N-substituted 3-(1H-imidazol-1-ylmethyl)indole carboxylic acid derivatives were prepared and evaluated for thromboxane A2 (TXA2) synthetase-inhibitory and histaminergic H1-blocking activity. Among the compounds synthesized, indole-6-carboxylic acid derivatives showed higher activities than the other positioal isomers of carboxylic acid. 1-[3-(4-Benzhyrdyl-1-piperazinyl)propyl]-3-(1H-imidazol-1-ylmethyl)-1H-indole-6-carboxylic acid (12) had the strongest thromboxane synthetase inhibitory activity (IC50=5×10-8M) and H1-blocking activity (IC50=8×10-9M).View full abstractDownload PDF (737K) -
Hirohiko KIMURA, Shuichi YOTSUYA, Shunji YUKI, Hideo SUGI, Itaru SHIGE ...1995 Volume 43 Issue 10 Pages 1696-1700
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSNovel N-(2-sulfonylamino-5-trifluoromethyl-3-pyridyl)carboxamide derivatives have been prepared and evaluated as phospholipase A2 (PLA2) inhibitors. Among these compounds, IS-741 (sodium salt of 1j), which showed the highest and the most stable therapeutic effect on acute hemorrhagic pancreatitis induced by the closed duodenal loop method in rats, was selected as a candidate for further development.View full abstractDownload PDF (677K) -
Tameo IWASAKI, Kazuhiko KONDO, Takashi NISHITANI, Tooru KURODA, Kazuyu ...1995 Volume 43 Issue 10 Pages 1701-1705
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA series of arylnaphthalene lignans were synthesized and tested for hypolipidemic activity. The most potent compound (4b) (TA-7552) not only reduced serum cholesterol, but also increased high-density lipoproteins cholesterol in rats. The effective dose of 4b is 100 times less than that of cholestyramine. Structure-activity relationships are discussed.View full abstractDownload PDF (827K) -
Koichi MIYAZAKI, Motohiro KOBAYASHI, Tsugitaka NATSUME, Masaaki GONDO, ...1995 Volume 43 Issue 10 Pages 1706-1718
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSDolastatin 10 (1) is a potent antineoplastic pentapeptide. Novel dolastatin 10 analogs each modified at one of the constituent amino acid derivatives, were synthesized and their antitumor activity was evaluated against P388 leukemia in mice. The structural requirements for antitumor activity are discussed. Some of the analogs, 31c, 35c, 38b, and 50c showed excellent activity in vivo. Highly active 50c, which lacks the thiazole group of 1, was selected for further development as an antitumor agent.View full abstractDownload PDF (1669K) -
Toshimi SEKI, Takayuki TAKEZAKI, Rikio OHUCHI, Morinobu SAITOH, Tsutom ...1995 Volume 43 Issue 10 Pages 1719-1723
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSOptical isomers of TZC-1370 (1) were prepared from (R)- and (S)-1-(2-chlorophenoxy)-2, 3-epoxypropane. When given intravenously to anesthetized rats, the (S)-isomer was about 40 times more potent in terms of β-blocking activity than the (R)-isomer, while their hypotensive activities were equipotent with that of the racemic compound, TZC-1370.View full abstractDownload PDF (780K) -
Tetsuyuki UNO, Yasushi OZEKI, Yasuo KOGA, Gil-Namg CHU, Minoru OKADA, ...1995 Volume 43 Issue 10 Pages 1724-1733
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA search for potent inhibitors of release of 12(S)-hydroxyeicosatetraenoic acid (12-HETE), which plays an important role in the pathogenesis of various circulatory disorders and arteriosclerosis, led us to 6-[4-(1-cyclohexyl-5-tetrazolyl)butoxy]-3, 4-dihydro-2(1H)-quinolinone (cilostazol) and 2(1H)-quinoinone derivatives having an azole group in the side chain. Many 2(1H)-quinolilnone derivatives were synthesized and tested in vitro for the inhibitory activity in human platelets. 3, 4-Dihydro-6-[3-(1-o-tolylimidazol-2-yl)sulfinylpropoxy]-2(1H)-quinolinone (5k) was found to be one of the most potent inhibitors of 12-HETE release, being more potent than esculetin. In addition, the sulfoxide 5k showed in vivo inhibitory activity on platelet adhesion in rats. Since 5k is recemic, the enantiomers were prepared and their potencies were compared in vitro and in vivo. (S)-(+)-5k had the best pharmacological profile and was selected as a candidate drug for further development. The structure-activity relationships are discussed.View full abstractDownload PDF (1255K) -
Tsutomu WARASHINA, Tadataka NORO1995 Volume 43 Issue 10 Pages 1734-1737
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe roots of Cynanchum caudatum M. (Asclepiadaceae) afforded eleven new pregnane glycosides which had cynanchogenin, caudatin, 12-O-benzoyllineolon and 12-O-benzoyldeacylmetaplexigenin as the aglycone moiety and 2, 6-dideoxy-3-O-methylhexopyranoses as component sugars. The structures of these compounds were elucidated by spectroscopic methods and from chemical evidence.View full abstractDownload PDF (627K) -
Yasunori YAOITA, Masao KIKUCHI1995 Volume 43 Issue 10 Pages 1738-1743
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSEight new eremophilenolides, 6β-angeloyloxy-3β, 9α-dihydroxyeremophil-7(11)-en-12, 8β-olide (1), 6β-angeloyl-oxy-3β, 9β-dihydroxyeremophil-7(11)-en-12, 8β-olide (2), 6β-angeloyloxy-3β, 8β, 9β-trihydroxyeremophil-7(11)-en-12, 8α-olide (3), 6β-(3'-chloro-2'-hydroxy-2'-methylbutyloyloxy)-3β-hydroxyeremophil-7(11)-en-12, 8β-olide (4), 6β-epoxyangeloyloxy-3β-hydroxyeremophil-7(11)-en-12, 8β-olide (5), 3β-hydroxy-6α-methoxyeremophil-7(11)-en-12, 8β-olide (6), 3β-hydroxy-6β-methoxyeremophil-7(11)-en-12, 8α-olide (7) and 8β-hydroxy-3-oxoeremophil-7(11)-en-12, 8α-olide (8) were isolated from the dried rhizomes of Petasites japonicus MAXIM. (Compositae) together with a new eremophilane-type sesquiterpenoid, 3β-hydroxy-8-oxoeremophil-6-en-12-oic acid methyl ester (9). Compound 4 is the first chlorine-containing eremophilenolide derivative isolated from natural sources. The structures of these compounds were elucidated by spectroscopy.View full abstractDownload PDF (892K) -
Hiroaki KITAOKA, Kazumi OHYA, Hideo HAKUSUI1995 Volume 43 Issue 10 Pages 1744-1750
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSNafagrel hydrochloride exists as both a hemihydrate and monohydrate. Conversion from the hemihydrate to the monohydrate is not reversible, and both hydrates can coexist in stable equilibrium between 23% relative humidity (RH) and 64% RH. In order to clarify the dehydration behavior, the kinetics of the thermal dehydration of the hydrates was studied by means of isothermal gravimetry at atmospheric pressure with a controlled water vapor pressure. This revealed that dehydration did not depend on absolute humidity but on RH. The dehydration of the hemihydrate proceeded by two-dimensional gorwth of the nuclei, A2, but the mechanism of monohydrate dehydration changed from A2 to a two-dimensional phase boundary, R2, with an increase in RH. The dehydration of the monohydrate proceeded by R2, resulting in the production of the hemihydrate at 6.5% RH or above. These kinetic analyses showed that the monohydrate dehydrated faster than the hemihydrate.View full abstractDownload PDF (740K) -
Kimei HAYASHI, Kumi ARAKANE, Noboru NAITO, Tetsuo NAGANO, Masaaki HIRO ...1995 Volume 43 Issue 10 Pages 1751-1754
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSBecause an amphiphile with a positive or negative charge, shch as dialkylphosphate or stearylamine, is often added to liposomal phosphatidylcholine (PC) dispersions to prevent aggregation of the liposomes, we investigated the long-term stability of liposomes prepared from saturated PC in the presence of various amphiphiles. On storage of these liposomes at 40°C, PC was gradually hydrolyzed by dialkylphosphate, a negatively charged lipid, while neither stearylamine, a positively charged lipid, nor a non-charged lipid hydrolyzed PC at all. This hydrolysis of PC was examined using dialkylphosphates of various alkyl chain lengths (C10, C12, C14, C16, C18 and C20) and PC with different fatty acyl chain lengths (C14, C16 and C18). The rate of hydrolysis was maximum when the alkyl chain length of dialkylphosphate was almost equal to the fatty acyl chain length of PC. That is, the hydrolysis of dimyristoyl (C14) and dipalmitoyl (C16) acyl chains of PC was accelerated most by the incorporation of dimyristylphosphate (C14) and dipalmitylphosphate (C16), respectively. Distearoyl (C18) acyl chains of PC were hydrolyzed effectively by the incorporation of distearylphosphate (C18) as well as dipalmitylphosphate (C16). The hydrolysis did not occur when methyl dipalmitylphosphate was added instead of dipalmitylphosphate, or when the liposomal structure was decomposed by adding ethanol. These results suggest that dialkylphosphate and PC are aligned head to tail in liposomes and that the phosphate functional group causes the hydrolysis of the esters of PC.The incorporation of cholesterol into PC bilayers suppressed the hydrolysis of PC above the phase transition temperature (Tc) of PC, but increased it below the Tc. The hydrolysis of PC by dialkylphosphate appears to depend on membrane fluidity and to be accelerated with increased membrane fluidity, because cholesterol reduces the fluidity of the liposomal membrane above the Tc and enhances it below the Tc.View full abstractDownload PDF (736K) -
Kumi ARAKANE, Kimie HAYASHI, Noboru NAITO, Tetsuo NAGANO, Masaaki HIRO ...1995 Volume 43 Issue 10 Pages 1755-1758
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSLiposomes were prepared from egg phosphatidylcholine (PC) for investigation of their long-term stability. When egg PC liposomes were incubated at 40°C, lowering of the pH was observed with a corresponding change in appearance. This pH lowering was suggested to be induced by peroxidation of the unsaturated fatty acyl chains in egg PC because : 1) the pH lowering was prevented by incorporation of α-tocopherol into liposomes or bubbling nitrogen into the liposomal dispersion at neutral pH; 2) the liposomes prepared from completely hydrogenated soya PC (CH-Soya PC) showed no change in pH under the same conditions. The relationship between the pH lowering and lipid peroxidation was also supported by the formation of thiobarbituric acid-reactive substances (TBA-RS) and the accumulation of carbonyl compounds in liposomes. The amount of TBA-RS reached a maximum after about 5 days' storage and then decreased gradually, while the pH lowering and production of carbonyl compounds in the liposomal dispersion continued for 20d. These results indicate that production of TBA-RS does not directly correlate with pH lowering in the liposomal dispersion; rather TBA-RS might be decomposed into secondary peroxidation products, such as carbonyl compounds, which may affect the pH of the liposomal dispersion.View full abstractDownload PDF (671K) -
Kazumi DANJO, Fumio HIGUCHI, Akinobu OTSUKA1995 Volume 43 Issue 10 Pages 1759-1763
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWe investigated the in vitro drug release from mixed polymer films using lidocaine (LC), which is poorly water-soluble. The mixed polymer films consisted of various ratios of hydroxypropylcellulose (HPC) and hydroxypropylmethylcellulose phthalate (HPMCP).The effects of the presence glycyrrhizic acid (GL) or polyethylene glycol (PEG) in the films upon LC release were also studied. LC crystallinity decreased in the polymer film and this decrease was remarkable in the presence of GL, resulting in an amorphous state.During the initial stage, drug release was regarded as a zero-order dissolution. The apparent release rate constant, ka, varied with the ratios of the two polymers and the amount of additives as well as with the pH of the test solution. The results indicated that GL enhanced the dissolution rate of LC from mixed polymer films, which may be due to the formation of an amorphous state. On the other hand, since PEG is a surfactant, the enhanced wettability of the polymer by the buffered solutions may have caused the increased dissolution rate.View full abstractDownload PDF (686K) -
Satoru WATANO, Takashi MORIKAWA, Kei MIYANAMI1995 Volume 43 Issue 10 Pages 1764-1771
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe kinetics of granule growth in fluidized bed granulation with moisture control was theoretically investigated. A population balance equation, in which moisture content was taken into consideration for the coalescence probability of two colliding granules, was proposed. The effects of damping speed and operation tiem on granule growth during moisture fixed command control were numerically examined. It was found that an increase in operation time resulted in an enlargement of granule diameter and a narrow size distribution during the damping process, but no significant growth was observed in the moisture fixed command control process. By contrast, a decrease in the operation time (large damping speed) caused small granule growth in the damping process, but a large growth in the moisture control process. The theory also showed good agreement with experimental granulation data for pharmaceutical powders.View full abstractDownload PDF (994K) -
Tadatsugu TANINO, Yoshihiro AOKI, Yoshihiro FURUYA, Koji SATO, Toyohik ...1995 Volume 43 Issue 10 Pages 1772-1779
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA study was made on the capping of tablets containing d-α-tocopheryl acid succinate. The study determined that capping occurs due to insufficient air escape from the granules during high-speed tablet compression. To prevent this, removal of air in the granules was necessary before tableting, and thus a degassing method by compaction was studied. In consideration of the long time required for the air to escape from the granules by compaction, a slow but continuous compacting force is thought to be more effective for degassing than an instantaneous high compression force. Consequently, a system to expel the air from the lubricated granules by compaction due to the weight of the upper punch itself was established before the pre-compression roller stage, and its effect was evaluated. This system achieved efficient degassing of the granules before tableting and completely prevented the capping of tablets containing d-α-tocopheryl acid succinate at a high concentration.View full abstractDownload PDF (1756K) -
Shigeki KOBAYASHI, Keiichiro SAMESHIMA, Yoko ISHII, Akira TANAKA1995 Volume 43 Issue 10 Pages 1780-1790
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe differences in biological activities among polychlorinated dibenzo-p-dioxins (dioxins) are strongly dependent on the substitution pattern of chlorine at various positions on the parent dibenzo-p-dioxin molecule. The absolute hardness, η, of dioxins shows a good correlation with the potency of biological activity and the chlorine substitution pattern. The result means that the soft dioxins have a small HOMO-LUMO gap, and are more toxic than the hard dioxins. Therefore, the values of absolute hardness, η, of dioxins can be used to predict their toxic potency (dioxin hardness). Moreover, we show that the absolute hardness-absolute electronegativity (η-χ) diagrams, as an activity coordinate, play an important role as a new measure in the assessment of the toxicity and potency of the biological activity of dioxins.View full abstractDownload PDF (1332K) -
Abdel-Monem El-Hosany EL-ASKALANY, Ahmed Mohamed ABOU EL-MAGD1995 Volume 43 Issue 10 Pages 1791-1792
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe composition and stability constants of the complexes of Zn(II), Pb(II), Cd(II) and Cu(II) with hematoxylin have been studied using direct current polarography and differential pulse polarography. The results showed the formation of 1 : 2 (M : L) complexes for Zn(II) and Pb(II), and a 1 : 6 (M : L) complex for Cd(II). However, the formation of copper-hematoxylin complex is irreversible. The values of the formation constants for the above complexes at 298, 308 and 318K were calculated as well as the relevant thermodynamic parameters.View full abstractDownload PDF (409K) -
Naoyuki HARADA, MITSUYA HONGU, Takashi TANAKA, Tatsuo KASHIDA, Naoko N ...1995 Volume 43 Issue 10 Pages 1793-1796
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIn an attempt to improve the effectiveness and bioavailability of 6-mercaptopurine, various kinds of water-soluble analogues, such as 6-S-aminoacyloxymethyl mercaptopurine derivatives (3a-m) and 6-S, 9-disubstituted derivatives (7a, b and 9a, b), were synthesized. These compounds were evaluated for activity to augment antitumor immunity by using a double grafted tumor system. Antitumor activities against solid tumors (sarcoma 180 and colon 26) were also evaluated. Many compounds exhibited potent activities in both test systems. In particular, the aminopropionate derivative (3a) and the L-glutamate derivative (3f) showed significant enhancement of antitumor immunity together with potent antitumor activities.View full abstractDownload PDF (630K) -
Kazuhiko TAKATORI, Sanae TOYAMA, Seishiro FUJII, Masahiro KAJIWARA1995 Volume 43 Issue 10 Pages 1797-1799
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSStereochemical detection and separation of the enantiomers of DL-amino acids were performed using a high-performance liquid chromatograph (HPLC) equipped with a chiral column and a circular dichroism spectrophotometer as a detector. Various racemic amino acids were separated by the chiral column and all L-amino acids and D-amino acids were detected as positive and negative circular dichroism peaks, respectively. Mixtures of two amino acids, DL-norleucine and DL-norvaline, DL-phenylglycine and DL-dopa, and glycine and DL-leucine were also analyzed.View full abstractDownload PDF (465K) -
Diraviam Patric RAJA, Visuvasam Soosai MANICKAM, Alexis John DE BRITTO ...1995 Volume 43 Issue 10 Pages 1800-1803
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSClerodane glycosides and flavonoids in Dicranopteris pedata and three varieties of D. linearis were investigated. All the ferns contained a new glycoside, (6S, 13S)-60[6-O-acetyl-β-D-glucopyranosyl-1(1→4)-α-L-rhamnopyranosyloxy]-13-[α-L-rhamnopyranosyl-(1→4)-β-D-fucopyranosyloxy]-cleroda-3, 14-diene, as a chemical marker of this group. Flavonoids were limited to flavonol 3-O-glycosides. The ferns and isolated flavonoids are as followes;D. pedata : afzelin, quercitrin. D. linearis var. brevis : afzelin, quercitrin. D. linearis var. tenuis : quercitrin, isoquercitrin. D. linearis var. sedastiana : astragarin, isoquercitrin, rutin, kaempferol 3-O-(4-O-p-coumaroyl-3-O-α-L-rhamnopyranosyl)-α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranoside.View full abstractDownload PDF (586K) -
Ken-ichi IZUTSU, Sumie YOSHIOKA, Shigeo KOJIMA1995 Volume 43 Issue 10 Pages 1804-1806
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe effects of cryoprotectants (sugars and polymers) on the eutectic crystallization of NaCl/water systems were studied by differential scanning calorimetry (DSC) and broad-line pulsed NMR. Thermal analysis of frozen NaCl solutions showed a melting peak of eutectic NaCl/water systems at around -21°C. The addition of various cryoprotectants inhibited the eutectic crystallization of the NaCl solution. The concentrations of polymers (dextran, polvinylpyrrolidone and Ficoll) required to inhibit eutectic crystallization were slightly higher than those of sugars (glucose, sucrose, trehalose and lactose). The proportions of liquid-phase protons present in frozen H2O and D2O sulutions, determined by broad-line pulsed NMR, showed that the addition of sugar inhibits eutectic crystallization of NaCl/water systems through the formation of an amorphous mixture containing NaCl, sugar and water between the ice crystals.View full abstractDownload PDF (593K) -
Yukiya YAMAGUCHI, Kenji SUGIBAYASHI, Takahiro TAKEDA, Toshinobu SEKI, ...1995 Volume 43 Issue 10 Pages 1807-1809
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe in vitro release characteristics of a model hydrophilic drug, clonidine hydrochloride, from pressure sensitive adhesive (PSA) matrices prepared by two coating methods, direct coating on a backing layer and transfer coating (coating on a liner layer and transfer of the resulting PSA onto a backing layer), with different drying temperatures were measured and evaluated. Hydrophilic polymer, polyethylene glycol (PEG), hydroxypropyl cellulose (HPC) or polyvinyl pyrrolidone (PVP) was added to the matrices to increase the drug release rate. A lower drying temperature showed a higher release rate. Each polymer increased the release rate compared to control (without polymer). A PSA matrix with HPC showed a low initial burst followed by a prolonged release, whereas those with PEG and PVP exhibited a high initial burst and a subsequent low release rate. The difference in the initial burst was related, to a considerable degree, to the affinity of the matrices against water. It was also related to the amount of drug on the matrix surface. The transfer coating and addition of HPV were useful in suppressing the high initial burst and in maintaining a high sustained release rate of the drug from the PSA matrices.View full abstractDownload PDF (636K) -
Susumu ISHIMITSU, Natsuko OHMORI, Sumiko TSUJI, Tadashi SHIBATA1995 Volume 43 Issue 10 Pages 1810-1812
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWhen indigo carmine (B-2) was illuminated in the presence of phenylalanine in 0.1 M citrate buffer (pH 4.0), p-tyrosine, m-tyrosine and o-tyrosine were identified as hydroxylated products. However, ten other food colors did not form tyrosine isomers. The hydroxylation of B-2 was pH-dependent, and the maximum rate was found at around pH 4.0. Replacement of air with nitrogen gas completely prevented the formation of tyrosine isomers and the decomposition of B-2. In contrast, oxygen gas accelerated both the hydroxylation and the decomposition.The addition of superoxide dismutase or catalase to this system prevented hydroxylation. Chemical scavengers of the hydroxyl radical (HO·) prevented the hydroxylation. On the other hand, a singlet oxygen scavenger had no significant effect. The above results suggest that the formation of HO· may occur in the photochemical reaction system in the presence of B-2 under aerobic conditions, and that a superoxide radical and hydrogen peroxide may be involved in the HO· formation.View full abstractDownload PDF (553K) -
Yumiro KIMURA, Toshihiko AKIHISA, Ken YASUKAWA, Michio TAKIDO, Toshita ...1995 Volume 43 Issue 10 Pages 1813-1817
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFive hydroxylated sterols, stigmastane-3β, 6α-diol, poriferastane-3β, 6α-diol, stigmast-5-ene-3β, 4β-diol, poriferast-5-ene-3β, 4β-diol, and poriferasta-5, 25-diene-3β, 4β-diol, the latter four of which are new naturally occurring compounds, were isolated from the unsaponifiable lipid of the seed extract of Trichosanthes kirilowii MAXIM. The structures were determined by spectral and chemical methods.View full abstractDownload PDF (750K) -
Akira KAJI, Kengo KIMURA, Tomoki IWATA, Noriki KIRIYAMA1995 Volume 43 Issue 10 Pages 1818-1820
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAsterriquinone (ARQ); 2, 5-bis[1-(1, 1-dimethyl-2-propenyl)-1H-indol-3-yl]-3, 6-dihydroxy-2, 5-cyclohexadiene-1, 4-dione and ARQ monoacetate are metabolites from mycelium of Aspergillus terreus IFO 6123. ARQ diacetate was converted into ARQ monoacetate by treatment with 5% aq. NaHCO3 in pyridine at 80°C for 5 min, and the yield was 93.4%. Similarly, by treatment with 5% aq. NaHCO3 in acetone at room temperature, 2, 5-diacetoxy-p-xyloquinone and 2, 5-diacetoxy-p-benzoquinone were converted into 2-acetoxy-5-hydroxy-p-xyloquinone (yield, 85.8%) and 2-acetoxy-5-hydroxy-p-benzoquinone (yield, 66.7%), respectively.View full abstractDownload PDF (439K) -
Toshiya TAKAHASHI, Masami MURAOKA, Magdalena CAPO, Kenji KOGA1995 Volume 43 Issue 10 Pages 1821-1823
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSEnantioselective and diastereoselective Darzens reaction mediated by chiral lithium amides was achieved between tert-butyl chloroacetate and aromatic aldehydes to give the corresponding trans-glycidic esters in up to 84% enantiomeric excess.View full abstractDownload PDF (476K) -
Masanori SAMOTO, Mayumi NAGANO, Yoko SUZUKI, Osamu TAMURA1995 Volume 43 Issue 10 Pages 1824-1826
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSDiels-Alder reactions of ethyl (E)-3-(1, 3-benzothiazol-2-yl)-3-cyanopropenoate (2) as a 1-aza-1, 3-butadiene are described. The diene (2), bearing electron-withdrawing ester group, reacts with electron-rich dienophiles (3a-d) under extremely mild conditions to give corresponding cycloadducts (4a-d) in high yields with high regio- and endo-selectivities. Treatment of 2 with electron-donating allyl alcohols (5a, b) causes tandem transesterification and intramolecular cycloaddition to afford cis-fused polycyclic systems (6a, b) in one step.View full abstractDownload PDF (436K) -
Hiroki UMEMIYA, Emiko KAWACHI, Hrioyuki KAGECHIKA, Hiroshi FUKASAWA, Y ...1995 Volume 43 Issue 10 Pages 1827-1829
Published: October 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS4-[5H-2, 3-(2, 5-Dimethyl-2, 5-hexano)-5-methyldibenzo[b, e]diazepin-11-yl]benzoic acid (4) enhanced the differentiation-inducing activity of retinoic acid (1) and of a synthetic retinoid Am80 (2) toward human promyelocytic leukemia cells HL-60, although 4 alone did not induce differentiation. The synergistic effect of 4 on the activities of retinoids was also seen in suppression of proliferation of HL-60 cells.View full abstractDownload PDF (522K)
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