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Volume 35, Issue 2
Displaying 1-50 of 73 articles from this issue
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NORIO KAWAHARA, TAKAKO SHIMAMORI, TSUNEO ITOH, HIROAKI TAKAYANAGI, HAR ...1987 Volume 35 Issue 2 Pages 457-467
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSMethyl isocrotonate derivatives prepared from various 1, 2-ethylenediamines, ο-phenylenediamines, 2-aminoethanols or ο-aminophenols with dimethyl acetylenedicarboxylate were easily converted to pyrido [1, 2-a] pyrazines, pyrido [1, 2-a] quinoxalines, pyrido [2, 1-c] -1, 4-oxazines, pyrido- [2, 1-c] -1, 4-benzoxazines, respectively, and other cyclization compounds by means of thermal reactions.View full abstractDownload PDF (1456K) -
NAOKI TENO, SATOSHI TSUBOI, TOMOKO SHIMAMURA, YOSHIO OKADA, YOSHIMI YA ...1987 Volume 35 Issue 2 Pages 468-478
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSThree S-peptide analogues of bovine pancreatic ribonuclease A (RNase A), [Nle1] [Lys7] S-peptide (I), [Lys1] [Nle7] S-peptide (II) and [Nle1] [Nle7] S-peptide (III), were synthesized by the fragment condensation method and their ability to reactivate S-protein was examined. It was found that Lys1 and Lys7 both have roles in the reactivation of S-protein.View full abstractDownload PDF (1873K) -
TAKEHIRO SANO, JUN TODA, NORIAKI KASHIWABA, TAKESHI OHSHIMA, YOSHISUKE ...1987 Volume 35 Issue 2 Pages 479-500
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSTotal synthesis of erythrinan alkaloids was achieved by a strategy based on the Diels-Alder reaction of activated butadienes to a dioxopyrroline. The reaction of isoquinolinopyrrolinedione (15) with 1, 3-bis-O-substituted butadienes proceeded in a regiospecific and stereoselective manner to give erythrinan derivatives (20) and (21). Lithium borohydride reduction of the adduct (20) or (21), followed by acid hydrolysis afforded the enone (33). Mesylation of 33 and subsequent demethoxycarbonylation of 42 under neutral conditions gave the dienone (43). Meerwein-Ponndorf reduction of 43 and subsequent methylation afforded erysotramidine (2a) and 8-oxoerythraline (2b). Aluminum hydride reduction of the 8-oxo derivatives (2) furnished dl-erysotrine (1a) and dl-erythraline (1b).View full abstractDownload PDF (3118K) -
SHUUJI HARA, HIKARU OKABE, KUNIHIDE MIHASHI1987 Volume 35 Issue 2 Pages 501-506
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSPairs of enantiomers of nine aldoses were separated by gas-liquid chromatography on an OV-17 capillary column as the trimethylsilyl ethers of methyl 2- (polyhydroxyalkyl) -thiazolidine-4 (R) -carboxylates, which were obtained by the reaction of aldoses with L-cysteine methyl ester. This method was applied to the determination of the absolute configurations of the component monosaccharides of a Thladiantha saponin.View full abstractDownload PDF (908K) -
EISUKE SATO, YOSHIYA IKEDA, YUICHI KANAOKA1987 Volume 35 Issue 2 Pages 507-513
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSIrradiation of solutions of 3-and 6-substituted 2-pyridones (1) in the presence of methylene blue as a sensitizer under an oxygen atmosphere gave 3-substituted pyridine-2, 6- (1H, 3H) -diones (2) and 6-substituted pyridine-2, 3- (1H, 6H) -diones (3), respectively, which are probably derived from the intermediate endoperoxides (6).View full abstractDownload PDF (849K) -
ETSUO OISHI, AKIYA YAMADA, EISAKU HAYASHI, TAKEO HIGASHINO1987 Volume 35 Issue 2 Pages 514-523
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSNucleophiles were found to react with 7- (methylsulfonyl) -1-phenyl-1H-1, 2, 3-triazolo [4, 5-d] -pyridazine (1) in three ways, depending on the nature of the reagent. One is substitution of the methylsulfonyl group in 1 by the reagent. The second one is addition of the reagent to the 4, 5-double bond in 1. The third one is the addition of the reagent, followed by ring fission of the pyridazine moiety.
Thus, the reaction of 1 with sodium methoxide resulted in substitution of the methylsulfonyl group, giving 7-methoxy-1-phenyl-1H-1, 2, 3-triazolo [4, 5-d] pyridazine. (2). The addition was found to proceed in the reaction with alkylmagnesium halides and hydrazines, giving the corresponding 4-alkyl- (3a-d) and 4-hydrazino-4, 5-dihydro-7- (methylsulfonyl) -1-phenyl-1H-1, 2, 3-triazolo [4, 5-d] -pyridazines (4a, b), respectively. The reaction with primary and cyclic amines resulted in ring fission, giving the corresponding 4- (alkyliminomethyl) - (5b, c) and 4- [di (cyclic amino) methyl] -5- (methylsulfonylmethyl) -1-phenyl-1 H-1, 2, 3-triazoles (6d-f), respectively.
On the other hand, the reaction of 7-chloro-1-phenyl-1H-1, 2, 3-triazolo [4, 5-d] pyridazine (7) with sodium methoxide, hydrazine, and amines resulted in the substitution of the chlorine atom, giving 2, 7-hydrazino- (11), and 7-alkylamino-1-phenyl-1H-1, 2, 3-triazolo [4, 5-d] pyridazines (12a-g), respectively, but neither addition nor ring fission was observed.View full abstractDownload PDF (1083K) -
KAZUYUKI HIDAKA, MIYOKO ITO, YOKO MATSUDA, HIROSHI KOHDA, KAZUO YAMASA ...1987 Volume 35 Issue 2 Pages 524-529
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSNovel triterpenoid saponins, ilexsaponins B1, B2 and B3, have been isolated from the roots of Ilex pubescens. Degradative and spectroscopic studies have established their structures as shown in formulae 5, 6, and 7. Ilexsaponin B3 was found to possess an activity against experimental hypercholesteremia in mice.View full abstractDownload PDF (665K) -
HIROSHI TOMISAWA, HIROSHI HONGO, TOSHIMITSU HATANO, HIROTO NAKANO, REI ...1987 Volume 35 Issue 2 Pages 530-534
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSStudies aimed at the synthesis of 6-azabicyclo [3.2.1] octane derivatives from 1-alkyl-2 (1H) -pyridones (Ia-d) were carried out. Reactions of Ia-d with fumaric acid monomethyl ester and acrylic acid gave 6-alkyl-8-endo-methoxycarbonyl-7-oxo-6-azabicyclo [3.2.1] oct-2-ene-2-carboxylic acids (VIIa-d) and 6-alkyl-7-oxo-6-azabicyclo [3.2.1] oct-2-ene-2-carboxylic acids (Xa-d), respectively.View full abstractDownload PDF (501K) -
Studies on Peptides. CXLVII. Synthesis of Valosin, a Novel 25-Residue Peptide from Porcine IntestineKENICHI AKAJI, MICHINORI TANAKA, SHOICHIRO SUMI, MASAFUMI KOGIRE, KYOI ...1987 Volume 35 Issue 2 Pages 535-543
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSA 25-residue peptide isolated from porcine intestine, designated valosin, was synthesized by assembling seven peptide fragments of established purity, followed by deprotection with 1 M trifluoromethanesulfonic acid in trifluoroacetic acid. γ-Cycloheptylglutamate, [Glu (OChp)], was employed to suppress pyrrolidone formation during fragment condensation. Before deprotection, Met (O) was reduced with phenylthiotrimethylsilane and trimethylsilyl trifluoromethanesulfonate. The effect of the synthetic peptide on arterial pressure, blood flow in the superior mesenteric artery, pancreatic capillary blood flow and pancreatic exocrine secretion was examined in dogs, but no significant dose-dependent response was observed. In rats, synthetic valosin stimulated pancreatic secretion, but showed no anti-gastric activity.View full abstractDownload PDF (1459K) -
CHUZO IWATA, MINORU YAMADA, TAKAFUMI FUSAKA, KAZUYUKI MIYASHITA, AYATS ...1987 Volume 35 Issue 2 Pages 544-552
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSTotal synthesis of (±) -solavetivone (1), a spirovetivane phytoalexin, was achieved. The metal catalyzed decomposition of the phenolic diazoketone (8) gave the spiro-dienone (6), selective reduction of which afforded the hydroxy-enone (5). The regio-and stereo-selective Birch reduction of 5 provided a high yield of the hydroxy-spiro-enone (9), whose structure was determined by X-ray crystal analysis. Compound 9 was transformed to (±) -1 and the aglycone A3 in several steps.View full abstractDownload PDF (1289K) -
Structures of Actinostemmosides A, B, C and D, Dammarane Triterpene Glycosides Isolated from the HerbMASAYO IWAMOTO, TOSHIHIRO FUJIOKA, HIKARU OKABE, KUNIHIDE MIHASHI, TAT ...1987 Volume 35 Issue 2 Pages 553-561
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSFrom the dried herb of Actinostemma lobatum MAXIM. (Cucurbitaceae), four dammarane-type triterpene glycosides named actinostemmosides A, B, C and D were isolated and their structures were elucidated on the basis of chemical and spectral evidence. Actinostemmosides A, B and C were identified as 20-Ο-β-D-glucopyranosides of 3β, 6α, 20, 27-tetrahydroxy- (20S) -dammar-24-ene, 3β, 7β, 20, 27-tetrahydroxy- (20S) -dammar-24-ene and 3β, 7β, 18, 20, 27-pentahydroxy- (20S) -dammar-24-ene, respectively, and actinostemmoside D, as the α-L-rhamnopyranosyl- (1→2) -β-D-glucopyranoside of 3β, 6α, 20, 27-tetrahydroxy- (20R) -dammar-24-ene.View full abstractDownload PDF (1199K) -
YASUYUKI KITA, OSAMU TAMURA, FUMIO ITOH, HITOSHI YASUDA, TAKASHI MIKI, ...1987 Volume 35 Issue 2 Pages 562-569
Published: February 25, 1987
Released on J-STAGE: February 12, 2010
JOURNAL FREE ACCESSIt is shown that vinyl sulfoxides undergo two novel modes of reactions induced selectively by the Ο-silylated ketene acetal used. Vinyl sulfoxides, on treatment with bulky tert-butyldimethylsilyl ketene acetals, undergo a Michael-Pummerer-type reaction to give γ-siloxy-γ- (phenylthio) esters, while with less bulky trimethylsilyl ketene acetals they undergo a double carbon-carbon bondforming reaction to give 3- (phenylthio) adipates. The reaction of related sulfoxides with Ο-silylated ketene acetals was also examined.View full abstractDownload PDF (1048K) -
YASUMITSU TAMURA, TAKAYUKI YAKURA, HIROAKI TERASHI, JUN-ICHI HARUTA, Y ...1987 Volume 35 Issue 2 Pages 570-577
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSOxidation of non-enolizable α, β-unsaturated carbonyl compounds and enolizable β-monosubstituted α, β-unsaturated carbonyl compounds with phenyl iodine (III) diacetate (PIDA) in methanolic potassium hydroxide gave α-hydroxydimethylacetal β-methoxy products, and oxidation of enolizable β, β-disubstituted α, β-unsaturated carbonyl compounds under the same conditions gaveα'-hydroxy products.View full abstractDownload PDF (1205K) -
KIYOTAKA KOYAMA, SHINSAKU NATORI1987 Volume 35 Issue 2 Pages 578-584
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSBesides chaetochromin A (1), a known mycotoxin and antitumor agent, three related bis (naphtho-γ-pyrone) derivatives named chaetochromins B (2), C (3), and D (4) were isolated from Chaetomium gracile. The structures were elucidated as the diastereomer, the 3-demethyl derivative, and the 2, 3-dehydro derivative of 1, respectively, chiefly on the basis of nuclear magnetic resonance data.View full abstractDownload PDF (702K) -
TAKAO KUROSAWA, UTAKO NIITSU, MASAHIKO TOHMA1987 Volume 35 Issue 2 Pages 585-592
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSThe thermal elimination of β-ketosulfoxide (2) afforded the α, β-unsaturated γ-ketoester (3) as a Michael acceptor (analogous to the key intermediate in Smith's estrone synthesis), which was condensed with 2-methylcyclopentane-1, 3-dione to give the adduct (4) having all carbon units of the aromatic steroidal skeleton. The Michael adduct was then cyclized in the presence of methanesulfonic acid to yield the novel estrapentaene (6) with a methoxycarbonyl group at the C-12 position. The estrapentaene (6) was converted to 12β- and 12α-methoxycarbonylestrones (25 and 26) and their estradiol derivatives (27 and 28) by selective reductions followed by demethylation.View full abstractDownload PDF (1040K) -
NOBUYUKI IMAI, KAZUO ACHIWA1987 Volume 35 Issue 2 Pages 593-601
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSN-Alkylpyrrolidines were obtained by one-pot synthesis through 1, 3-dipolar cycloaddition of the N-alkylazomethine ylide intermediates generated from N- (benzylidene) trimethylsilylmethylamine and alkyl halide or tosylate.View full abstractDownload PDF (842K) -
KANJI ISHIMARU, GEN-ICHIRO NONAKA, ITSUO NISHIOKA1987 Volume 35 Issue 2 Pages 602-610
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSTwo novel and closely related tannins, designated as acutissimins A (1) and B (2), have been isolated from various Fagaceous plants : Quercus acutissima, Q. miyagii, Q. stenophylla, Q. mongolica var. grosseserrata and Castanea crenata. Degradative and synthetic studies combined with 1H- and 13C-NMR spectrometry and various mass spectral measurements have permitted the assignments. of the structures, in which (+) -catechin (4) and the C-glycosylated ellagitannin, castalagin (3), are connected through a carbon-carbon linkage.View full abstractDownload PDF (1014K) -
Tannins and Related Compounds. LVI. Isolation of Four New Acylated Flavan-3-ols from Oolong Tea. (1)FUMIO HASHIMOTO, GEN-ICHIRO NONAKA, ITSUO NISHIOKA1987 Volume 35 Issue 2 Pages 611-616
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSA chemical examination of the aqueous acetone extract of commercial oolong tea has led to the isolation of four new acylated flavan-3-ols 1-4, together with the known compounds 5-13. On the basis of chemical and spectroscopic evidence, compounds 1-4 have been characterized as (-) - epiafzelechin 3-Ο-gallate (1), (-) -epicatechin 3-Ο- (4-Ο-methyl) -gallate (2), (-) -epicatechin 3-Ο-p-hydroxybenzoate (3) and (-) -epigallocatechin 3-Ο-cinnamate (4).View full abstractDownload PDF (603K) -
KIYOMI KAKIUCHI, MASAKI UE, MITSUNORI TAKEDA, TOSHIHIRO TADAKI, YUJI K ...1987 Volume 35 Issue 2 Pages 617-631
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSNew analogues related to quadrone (3), 3-methylenetricyclo [4.3.2.01.5] undecan-4-one (14), 4-methylenetricyclo [4.3.2.01, 5] undecan-3-one (15), and 2-methylenetricyclo [4.3.2.01, 5] undec-4-en-3-one (16), and novel propellane-and angular-type triquinanes, 3-methylenetricyclo [3.3.3.0] undecan-2-one (17), (E) -3-propylidene-and (E) -3- (5-carbomethoxy) pentylidenetricyclo [3.3.3.0] undecan-2-ones (18 and 19), (E) -5- (2-oxotricyclo [3. 3.3.0] undecan-3-ylidene) pentyl (E) -cinnamate (20), 2-methylenetricyclo [3.3.3.0] undecan-3-one (21), 4-methylene-2-oxatricyclo [3.3.3. 0] undecan-3-one (22), and 7-methylenetricyclo [6. 3. 0. 0, 1, 5] undecan-6-one (23), were readily synthesized through skeletal transformations, and showed antiproliferating activity. Biomimetic reactions of a model compound of 3, 2-methylenetricyclo [4.3.2.01, 5] undecan-3-one (8), with propanethiol, etc. were undertaken. Correlations of the activity of some polyquinanes with second-order rate constants of addition of L-cysteine and with the carbon-13 nuclear magnetic resonance chemical shifts of exo-methylene β-carbons are discussed.View full abstractDownload PDF (2259K) -
MASAMI SHIRATSUCHI, KIYOSHI KAWAMURA, TOSHIHIRO AKASHI, MIKIO FUJII, H ...1987 Volume 35 Issue 2 Pages 632-641
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSA series of dihydrobenzopyranyloxypropanolamines and dihydrobenzopyranylethanolamines containing a nitroxy moiety was synthesized. The cardiovascular effects of these compounds were investigated in anesthetized dogs. Some of the compounds exhibited hypotensive activity in combination with β-adrenergic blocking and vasodilating action. The structure-activity relationships are discussed.View full abstractDownload PDF (1316K) -
FUMIO SAKAMOTO, SHOJI IKEDA, RYOICHI HIRAYAMA, MASARU MORIYAMA, MIKIO ...1987 Volume 35 Issue 2 Pages 642-646
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSAs a new type of mecillinam prodrug, mecillinam (5-substituted 2-oxo-1, 3-dioxol-4-yl) methyl esters were prepared. These esters were found to produce at least 4-fold higher mecillinam levels in blood than mecillinam itself after oral administration to mice. Mecillinam (5-methyl-2-oxo-1, 3-dioxol-4-yl) methyl ester hydrochloride was hygroscopic, but its L-tartrate was not.View full abstractDownload PDF (723K) -
KAGARI FUJITA, SUSUMU KOBAYASHI, ICHIRO KUDO, KEIZO INOUE, SHOSHICHI N ...1987 Volume 35 Issue 2 Pages 647-653
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSFluorine-modified acetyl glyceryl ether phosphorylcholines (platelet activating factors; PAFs) were efficiently synthesized in an enantioselective manner by the coupling of a D-threitol.derivative with fluorinated long-chain alkoxy methanesulfonates. The introduction of a trifluoromethyl group at the terminal of the alkyl ether chain decreased the hypotensive activity and platelet activation considerably. As the number of fluorine atoms in the alkyl ether chain was increased, both activities were gradually restored, but no selective agonist was obtained from among the fluorinated PAFs.View full abstractDownload PDF (1031K) -
HIROSHI TSUJIBO, YOSHIAKI MIYAKE, KOSHI MARUYAMA, YOSHIHIKO INAMORI1987 Volume 35 Issue 2 Pages 654-659
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSBy the use of spontaneously hypertensive rats (SH rats) as a screening system, two hypotensive compounds were isolated from alcohol extract of the unossified horn of Cervus elaphus L. var. xanthopygus (Rokujo). One of the two compounds was identified as lysophosphatidyl choline (LPC). It was shown by gas chromatography that palmitic acid (C16 : 0) accounted for about half of the fatty acid content. Next, the effects of various LPCs on SH rats were examined. Eleven LPCs with C10 : 0 to C20 : 0 fatty acids were examined, and all except for those with C10 : 0 and C20 : 0 fatty acids showed the hypotensive effect (3 mg/kg, i.v.). In particular, C14 : 0 and C16 : 0-LPC showed rather potent activity. On the other hand, of the six LPCs with unsaturated fatty acids, only C16 : 1-LPC showed the hypotensive effect (3 mg/kg). It was concluded that at least a part of the hypotensive action of alcohol extract of Rokujo is due to LPC.View full abstractDownload PDF (789K) -
MUNEKAZU IINUMA, TOSHIYUKI TANAKA, KAZUHIRO ITO, MIZUO MIZUNO1987 Volume 35 Issue 2 Pages 660-667
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSTwelve flavonoids with three hydroxy and four methoxy groups located at C-2', 3', 4', 5, 6, 6', 7 (1-4), C-2', 3', 4', 5, 6', 7, 8 (5), C-2', 3, 4', 5, 5', 6, 7 (6-11) and C-2', 3, 4', 5, 5', 7, 8 (12) were synthesized to confirm the structure of NAS-3 and to investigate the spectral properties of the hepta-oxygenated flavonoids. The methods used to prepare the tetra-oxygenated benzaldehydes (14-19) for the B ring moieties are also described.View full abstractDownload PDF (1267K) -
MASAO HATTORI, SUMITRA HADA, YUE-ZHONG SHU, NOBUKO KAKIUCHI, TSUNEO NA ...1987 Volume 35 Issue 2 Pages 668-674
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSFrom a methanolic extract of the aril of Myristica fragrans HOUTT. (mace), the following new threo and erythro acyclic bis-phenylpropanoids were isolated : threo-2- (4-allyl-2, 6-dimethoxyphenoxy) -1- (4-hydroxy-3-methoxyphenyl) propan-1-ol (1a), erythro-2- (4-allyl-2, 6-dimethoxyphenoxy) -1- (4-hydroxy-3-methoxyphenyl) -1-methoxypropane (2b), erythro-2- (4-allyl-2, 6-dimethoxyphenoxy) -1- (4-hydroxy-3, 5-dimethoxyphenyl) propan-1-ol (3b), 2- (4-allyl-2, 6-dimethoxyphenoxy) -1- (4-hydroxy-3-methoxyphenyl) propane (4), erythro-2- (4-allyl-2-methoxyphenoxy) -1- (4-hydroxy-3-methoxyphenyl) propan-1-ol (5b), threo-1- (4-hydroxy-3, 5-dimethoxyphenyl) -2- [2-methoxy-4- (1 (E) -propenyl) phenoxy] propan-1-ol (6a) and erythro-2- (4-allyl-2, 6-dimethoxyphenoxy) -1- (3-hydroxy-4, 5-dimethoxyphenyl) propan-1-ol (7b). Contrary to a previous finding that Myristica species contain only an erythro type of acyclic bis-phenylpropanoids, we isolated both threo and erythro derivatives.View full abstractDownload PDF (957K) -
Inhibitors of Adenosine 3', 5'-Cyclic Monophosphate Phosphodiesterase in Daphne genkwa SIEB. et ZUCCTAMOTSU NIKAIDO, TAICHI OHMOTO, USHIO SANKAWA1987 Volume 35 Issue 2 Pages 675-681
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSLuteolin, luteolin-7-methylether and kaempferol 3-O-β-D- (6″-p-coumaroyl) glucopyranoside (tiliroside) were identified as adenosine 3′, 5′-cyclic monophosphate phosphodiesterase inhibitors contained in the flowers and buds of Daphne genkwa SIEB. et ZUCC. The assignments of the proton and carbon-13 nuclear magnetic resonance signals of tiliroside were confirmed by two-dimensional 1H-13C chemical shift correlation spectroscopy.View full abstractDownload PDF (756K) -
TOSHINOBU MIWA, MASAKI ICHIKAWA, MASANORI TSUNO, TEIICHI HATTORI, TAKE ...1987 Volume 35 Issue 2 Pages 682-686
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSA new chiral recognition column, with conjugated ovomucoid as the ligand, was developed. This column may be employed for the chiral resolution of acids as well as amines without derivatization. The retention time, capacity factor and resolution factor were dependent on pH, buffer strength and 2-propanol concentration of the mobile phase. For chlorpheniramine, a resolution factor of 1.5 was obtained.View full abstractDownload PDF (489K) -
MASARU NAKAMURA, SHUUJI HARA, MASATOSHI YAMAGUCHI, YASUYO TAKEMORI, YO ...1987 Volume 35 Issue 2 Pages 687-692
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSThe reactivity of pyruvic acid with 1, 2-diaminobenzenes was investigated as part of a survey of fluorogenic reagents for α-keto acids of biological importance. Of eight 1, 2-diaminobenzenes tested, 1, 2-diamino-4, 5-methylenedioxybenzene was found to be the best reagent in terms of sensitivity and reactivity. The reagent reacts with α-keto acids in an acidic solution to produce the corresponding fluorescent derivatives, which fluorescent most intensely in a neutral medium. The derivatives of ten α-keto acids can be separated within 18 min by reversed-phase high-performance liquid chromatography with isocratic elution. The detection limits for the acids are at femtomole levels for an injection volume of 10 μl. The fluorescent product from pyruvic acid was characterized as 3-methyl-6, 7-methylenedioxy-2 (1H) -quinoxalinone. The fluorescence properties of the product are also described.View full abstractDownload PDF (817K) -
JUN-ICHI ANZAI, SACHIKO TEZUKA, TETSUO OSA, HIDEKI NAKAJIMA, TADAYUKI ...1987 Volume 35 Issue 2 Pages 693-698
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSA potentiometric method for the determination of urea in human blood with an ion-sensitive field effect transistor coated with a urease-albumin membrane is described. The urea sensor exhibits a potentiometric response to urea concentrations in the range of 0.1-10 mM with a response time of ca. 3 min. Urea concentrations of diluted serum and plasma can be determined accurately with the sensor. Comparison with an official method (i.e. the urease-indophenol method) gave satisfactory results.View full abstractDownload PDF (661K) -
JUN YATSUYANAGI, KAZUHIKO IWAI, TAKETO OGISO1987 Volume 35 Issue 2 Pages 699-704
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSThe effect of zinc administration to rats on the acute inflammatory response to carrageenan in the pleural cavity was studied. The number of neutrophils mobilized into the pleural cavity was markedly reduced in a dose-dependent manner, whereas the volume of exudate formed significantly increased during the development of pleurisy. In the neutrophils isolated from zinc-treated rats, the mobilization capacity, phagocytic activity and concomitant O2- production were strongly inhibited accompanied with a slight increase in zinc content in the cells. These inhibitory effects of zinc on neutrophil functions and the increase in zinc content of cells were also observed in an in vitro system.
The viability of neutrophils obtained from zinc-treated rats slightly decreased, as was evidenced from leakage of cytoplasmic lactate dehydrogenase during the course of phagocytosis, suggesting that the neutrophils from zinc-treated rats may be more susceptible to cell damage during phagocytosis.View full abstractDownload PDF (875K) -
TAIKO AKAO, TERUAKI AKAO, KYOICHI KOBASHI1987 Volume 35 Issue 2 Pages 705-710
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSA bacterial strain capable of hydrolyzing glycyrrhizin (GL) to glycyrrhetic acid (GA) was isolated from human feces. This bacterium was identified as Eubacterium sp. The GL-hydrolyzing activity increased in parallel with the growth of this bacterium, which also produced β-D-glucuronidase (EC 3.2.1.31) acting on β-D-glucuronides of phenolic compounds such as phenolphthalein mono-β-D-glucuronide. GL-hydrolyzing activity was recovered in the supernatant fraction after disruption of this bacterium with a French press and was partially purified by means of ammonium sulfate fractionation, and Sephadex G-200 and octyl-Sepharose column chromatographies.
GL-hydrolyzing enzyme was separated from the β-D-glucuronidase which hydrolyzes β-D-glucuronides of phenolic compounds by octyl-Sepharose column chromatography, indicating that the GL-hydrolyzing enzyme is a novel type of β-D-glucuronidase.View full abstractDownload PDF (828K) -
YASUCHIKA MATSUDA, HIDEMI HOSHIKA, YOSHIO INOUYE, SHIGERU IKUTA, KAZUO ...1987 Volume 35 Issue 2 Pages 711-717
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSSarcosine oxidase (EC 1.5.3.1) produced by Bacillus sp. B-0618 was purified by ion exchange chromatography on diethyl aminoethyl-cellulose and gel filtration on Sephadex G-100 and G-150. The molecular weight of the enzyme was estimated to be 42000 by gel filtration on Sephadex G-150 and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The enzyme exhibited an absorption spectrum characteristic of flavoprotein. The enzyme showed the maximum activity at pH 8.5-9 and was stable at pH 7-10. The pI value was 4.7 as determined by isoelectric focusing. Although sarcosine is the preferred substrate, the enzyme also oxidized N-methyl-DL-alanine, N-methyl-L-leucine and N-methyl-DL-valine to lesser extents. The apparent Km values of sarcosine, N-methyl-DL-alanine, N-methyl-L-leucine and N-methyl-DL-valine were 12.2, 6.8, 106 and 173 mM, respectively. The enzyme was inactivated by N-bromosuccinimide, Zn2+, Fe3+ and Hg2+, but not by ethylenediaminetetraacetate, p-chloromercuribenzoate, monoiodoacetate or p-toluenesulfonylchloride.View full abstractDownload PDF (866K) -
EMI NAKASHIMA, KOICHI YOKOGAWA, FUJIO ICHIMURA, KOUICHI KURATA, HIDEKI ...1987 Volume 35 Issue 2 Pages 718-725
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSThe disposition characteristics of biperiden were investigated in rats, rabbits, beagles, and humans, and a physiologically based pharmacokinetic model was established by using the hepatic intrinsic clearance of unbound drug concentration and the tissue-to-plasma unbound concentration ratios. Protein-binding parameters and blood-to-plasma concentration ratios were determined, and linear parameters were obtained in beagles and humans over a wide concentration range. The hepatic intrinsic clearance of humans was predicted from the animal data. The coincidence of each tissue-to-plasma unbound concentration ratio between rats and rabbits was confirmed in the steady state, and the mean tissue-to-plasma unbound concentration ratios were used for the prediction of the plasma concentration-time courses of beagles and humans. The predicted lines fitted the observed plasma concentrations of beagles and a patient well after a single intravenous injection and repeated intramuscular administrations, respectively.View full abstractDownload PDF (999K) -
KEN-ICHI HOSOYA, NORIMASA SHUDO, KENJI SUGIBAYASHI, YASUNORI MORIMOTO1987 Volume 35 Issue 2 Pages 726-733
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSPoly (acrylic acid) gels containing 5-fluorouracil (5-FU) and Azone were prepared and the effects of Azone on 5-FU release from the gels and on 5-FU permeation across the skin were studied by in vitro and in vitro methods. 5-FU was released rapidly from the gels. The release rate of 5-FU from the gels was higher than that from a commercial ointment. Azone did not affect the in vitro drug release from the gels. Experiments on in vitro permeation of 5-FU across the hairless rat skin with vertical diffusion cells showed that addition of Azone to the gels markedly enhanced the 5-FU permeability, although a lag time of approximately 6 h was observed. Increasing the Azone concentration in the gels to 15% proportionally increased the permeability of 5-FU. More than 10 h was required to reach a steady-state blood level of 5-FU after administration of 5-FU-Azone gel topically. Pretreatment with Azone, however, shortened the lag time so that a steady-state level was reached sooner. The area under the blood concentration-time curve (AUC) after topical administration was comparable to that after oral administration.
These results suggest not only that Azone would be very useful for increasing the skin permeability and blood level of 5-FU, but also that Azone might be useful for developing transdermal therapeutic systems for the delivery of practically unabsorbable drugs.View full abstractDownload PDF (886K) -
YUKIHISA KURONO, YOSHIRO OZEKI, HIDETO YAMADA, TOSHIMASA TAKEUCHI, KEN ...1987 Volume 35 Issue 2 Pages 734-739
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSThe subdivision of R-type drugs, which inhibit the reaction of p-nitrophenyl acetate with an active site (R site) located near the tyrosine-411 residue of human serum albumin (HSA), is proposed based on the results of kinetic and fluorometric studies. We found two kinds of R-type drugs with regard to the influence on the reaction rate of 3, 5-dinitroaspirin (DA) at a site (U site) near the lysine-199 and tryptophan-214 (Trp-214) residues of HSA. One of them (R2-type drug, e.g., diazepam or medazepam) greatly accelerates the reaction of DA with HSA, and the other (R1-type drug, e.g., clofibric acid or octanoic acid) does not affect the reaction. The R2-type drug quenches the fluorescence originating from the Trp-214 residue in the U site of HSA, and the R1-type drug hardly influences this fluorescence. The acceleration of the reaction was considered to be due to the conformational change of the U site caused by binding of the R2-type drug to a part of the R site on HSA. Five benzodiazepines, 3 sulfonylureas, and 3 other drugs were classified into R1-type and R2-type drugs.View full abstractDownload PDF (837K) -
YOSHIFUMI WATANABE, TOSHIAKI OSAWA1987 Volume 35 Issue 2 Pages 740-747
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSSmall and large liposomes containing ricin or ricin A-chain (a toxic subunit of ricin) and having monoclonal anti-carcinoembryonic antigen (CEA) antibodies on the surface were prepared, and their effects on CEA-producing tumor cells, were examined in order to evaluate the efficacy of these liposomes as drug delivery systems. It was found that the large unilamellar liposomes (average diameter : 3000 Å) could not be internalized by the tumor cells, but were ruptured after specific binding to tumor cells through the monoclonal antibodies on the surface. On the other hand, the small unilamellar liposomes (average diameter : 800 Å) were found to be easily internalized by tumor cells.View full abstractDownload PDF (1108K) -
TETSUROU HANDA, HIROFUMI TAKEUCHI, YUICHI OHOKUBO, YOSHIAKI KAWASHIMA1987 Volume 35 Issue 2 Pages 748-755
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSA modification of the reversed-phase evaporation method (modified REV method) was developed for the preparation of lyophilized unilamellar liposomes. The encapsulation efficiencies of the liposomes after a dehydration (lyophilization) -rehydration procedure were satisfactorily high, and the liposome sizes were maintained nearly constant throughout the procedure. These results are different from those obtained with liposome samples prepared by the reversed-phase evaporation method. In the latter case, marked enlargement of liposome size and extensive leakage from liposomes were observed. The small amount of residual ether in the modified REV liposomes keeps the lipid membranes fluid even at freezing temperature. The fluidity is considered to play an important role in the protection of liposomes against aggregation, fusion and leakage.View full abstractDownload PDF (1112K) -
YUKIHIKO ARAMAKI, ASAICHI INABA, JUN-ICHI HOSODA, SEISHI TSUCHIYA1987 Volume 35 Issue 2 Pages 756-760
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSHeparan sulfate was purified from rat kidney cortex by a combination of affinity chromatography and ion exchange chromatography, and identified by cellulose acetate electrophoresis. As determined by the equilibrium dialysis method, heparan sulfate has two classes of binding sites for dibekacin and gentamicin, and has one class of binding site for amikacin. From the results of equilibrium dialysis using dextran sulfate and hyaluronic acid, the high affinity sites of heparan sulfate for gentamicin and dibekacin were considered to be the sulfate groups, and the low affinity sites to be the carboxyl groups.View full abstractDownload PDF (787K) -
SATOSHI OKADA, HIROSHI NAKAHARA, HIROSHI ISAKA1987 Volume 35 Issue 2 Pages 761-768
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSThe adsorption of various drugs on microcrystalline cellulose (MCC) suspended in aqueous solutions was investigated. Adsorption of diphenhydramine, chlorpheniramine, isoniazid, and p-aminobenzoic acid was very slight or negligible, whereas the adsorption of four phenothiazine derivatives (PTZs) was considerable, and that of acrinol was quite large. Except for chlorpromazine sulfoxide, adsorption isotherms for three PTZs and acrinol were all of the Freundlich type. Based on the Freundlich constants, k and 1/n, the adsorbability of those drugs on MCC was in the order acrinol>>chlorpromazine>triflupromazine>promazine. The slight differences in 1/n for those drugs suggest differences in the adsorption mechanisms. Further it was observed that the adsorption increases with increase of pH, and decreases with increase of ionic strength. In addition, the pH values for MCC suspended solutions decrease gradually with the addition of neutral salts. Thus, in the adsorption of PTZs and acrinol on MCC, the ion-exchange mechanism appeared to play an important role, but adsorption due to non-electrostatic forces should also be appreciable. Marked adsorption of acrinol on MCC can be interpreted in terms of the presence of polar groups capable of hydrogen-bond formation, and the coplanar arrangement of the acridine ring.View full abstractDownload PDF (1045K) -
YASUYUKI TSUDA, ETSUKO SUZUKI, KEIJI SEKIGUCHI1987 Volume 35 Issue 2 Pages 769-777
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSIt was confirmed that griseofulvin, sulfanilamide and theophylline form HF adducts with combining ratios of 1 : 1 (griseofulvin : HF), 1 : 2 (sulfanilamide : HF) and 1 : 3 and 1 : 2 (theophylline : HF). The thermal and other physico-chemical properties of these adducts and the recovered medicinals were investigated by differential scanning calorimetry, thermogravimetry, X-ray powder diffractometry, infrared spectroscopy and microscopy. Effective particle size reduction was achieved by desorbing HF from the adducts.View full abstractDownload PDF (1443K) -
YUJI TATEOKA, TOSHIYUKI KIMURA, KAZUHITO WATANABE, IKUO YAMAMOTO, ING ...1987 Volume 35 Issue 2 Pages 778-784
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSN- (or S-) Allyl derivatives of phenobarbital (PheB), amobarbital (AB) and thiopental (TP) were prepared, and their pharmacological activities (hypnotic activity and anticonvulsant activity against pentylenetetrazol-induced seizures) were investigated in mice. N-Monoallyl-substituted derivatives (MAPheB, MAAB and MATP) of PheB, AB and TP exhibited hypnotic and anticonvulsant activities. N, S-Diallylthiopental (N, S-DATP) possessed hypnotic activity, but failed to show anticonvulsant activity even at a dose of 250 mg/kg (i.p.). N, N '- Diallyl-substituted derivatives (DAPheB, DAAB and DATP) were devoid of not only the hypnotic activity, but also-the anticonvulsant activity. The interactions of these allyl derivatives with various barbiturates were then studied in order to characterize whether the allyl compounds have antagonistic or potentiating properties. MAPheB, DAPheB, MAAB and DAAB showed dose-dependent potentiation of the sleep induced by the corresponding mother compounds. All the allyl compounds tested prolonged the pentobarbital-induced sleeping time more than 7- to 19-fold as compared with the control. MAAB markedly prolonged the PheB-induced sleeping time by 25-fold, but it did not potentiate the barbital-induced sleep. These results indicate that N- (or S-) allyl derivatives of PheB, AB and TP interact differently with the barbiturates.View full abstractDownload PDF (951K) -
MITSUO NAKAO, YUKIKO GOTOH, YASUHIKO MATSUKI, AKIRA HIRATSUKA, TADASHI ...1987 Volume 35 Issue 2 Pages 785-791
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSThe metabolism of nitro-p-phenylenediamine (I), a constituent of hair dyes, was studied following its administration to male rats. Two major metabolites, N4-acetyl-2-nitro-1, 4-diaminobenzene (II) and N1, N4-diacetyl-1, 2, 4-triaminobenzene (IV), were isolated from the urine and identified. However, other N-acetyl regioisomers of II and IV, and the fully N-acetylated metabolite, 1, 2, 4-triacetylaminobenzene, could not be detected by high-pressure liquid chromatography. Further, N4-acetyl-1, 2, 4-triaminobenzene (III), a possible precursor of IV, could also not be detected in the urine.
After the administration of the possible intermediates produced through the metabolism of I, the metabolite IV was isolated and identified from the urine of the animals. Based on the results of the present investigation, the hair dye constituent I appears to be metabolized successively to II, III and IV by regioselective N4-acetylation and subsequent nitro reduction, followed by regioselective N1-acetylation, because rats given II or III excreted IV in the urine. Compound I might be also metabolized through an alternative pathway to IV via 1, 2, 4-triaminobenzene (VI) formed by direct nitro reduction, because IV was excreted as a urinary metabolite in rats given VI or its N1-monoacetylated product (III-1). Thus, the metabolism of I appears to proceed through regioselective N-acetylation of the amino groups.View full abstractDownload PDF (817K) -
MASAHITO FUKUNAGA, YASUO MIZUGUCHI, LERENA W. YIELDING1987 Volume 35 Issue 2 Pages 792-797
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSThe mutagenic activity of a series of aminoacridines was examined by the preincubation method with and without mammalian metabolizing enzymes in Salmonella tester strains. Without metabolizing enzymes, three acridines having an amino substituent at position 9 showed high activity in Salmonella typhimurium TA1537 and TA1977, and other acridines with amino substituents at position 2 or 3 were mutagenic but were less effective than the 9-aminoanalogs. The liver microsomal enzymes generally deactivated acridine mutagenicity in TA1537, but created a broad spectrum of mutagenicity if tested by the reversion of TA1535, the strain detecting base-pair substitution mutagens, and TA 1538, the strain detecting covalently bound frameshift mutagens.View full abstractDownload PDF (839K) -
CHIKAKO YOMOTA, YOSHIO ITO, MASAYUKI NAKAGAKI1987 Volume 35 Issue 2 Pages 798-807
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSInteractions of cationic surfactants with a branched polymer, arabate (Ar), and a linear polymer, chondroitin sulfate (Chs), were investigated by the potentiometric technique using surfactant ion-selective electrodes. The results indicated a highly cooperative nature in the binding process of n-dodecyltrimethylammonium ion (DOTMA +) with Chs, but not Ar, in spite of the similarity of the charge density parameter, ζ, between the two polymers. The cooperativity parameter, u, was estimated from the Zimm-Brag theory in the present experimental system to be 3.5 for Ar and 200 for Chs, each of which was independent of the concentration of added salt. The binding constant, K, in the case of the Chs-DOTMA +system was considerably larger than that of the Ar-DOTMA + system. This difference of binding behavior of DOTMA+ to Ar and to Chs was considered to be mainly due to the structural difference between the two polymers.View full abstractDownload PDF (1032K) -
TOSHINOBU AOYAMA, MASAYOSHI HORIOKA, SHINGO NAGAMITSU1987 Volume 35 Issue 2 Pages 808-813
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSAs a part of our studies to develop anticancer agents with prolonged action and reduced side effects, we examined the macromolecular complex of doxorubicin and heparin. Formation of a complex of doxorubicin and heparin was confirmed by HIAC, infrared, ultraviolet, differential scanning calorimetry, energy micro analysis X-ray and high performance liquid chromatography analysis. If the molecular weight of heparin is assumed to be 9800, one molecule of heparin binds 16 molecules of doxorubicin.View full abstractDownload PDF (636K) -
KENICHI MIYAMOTO, NOBUHARU KISHI, RYOZO KOSHIURA, TAKASHI YOSHIDA, TSU ...1987 Volume 35 Issue 2 Pages 814-822
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSSixty-three tannins and related polyphenols were intraperitoneally injected into mice at 4 d before intraperitoneal sarcoma-180 cell inoculation, and their antitumor activities were evaluated. The condensed tannins and related compounds all showed negligible activity. As regards the hydrolyzable tannins, active compounds were found among ellagitannins. In particular, dimeric ellagitannins such as oenothein B, rugosin E, rugosin D, gemin A and coriariin A showed significantly higher antitumor activity than agrimoniin, which we previously reported as an antitumor tannin. Coriariin A, which has four galloyl groups instead of two hexahydroxydiphenoyl groups of agrimoniin, showed the strongest activity. It seems to be essential for marked antitumor activity that ellagitannins should possess a dimeric structure with several galloyl groups on the glucose core.View full abstractDownload PDF (752K) -
TAKAO SAKAMOTO, HIDEO NAGATA, YOSHINORI KONDO, MASAFUMI SHIRAIWA, HIRO ...1987 Volume 35 Issue 2 Pages 823-828
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSThe palladium-catalyzed reactions of 4-bromo-and 5-bromothiazoles, as well as 4-bromo-and 5-bromooxazoles with terminal acetylenes gave ethynyl derivatives in 43-89% yields, whereas the reactions of 2-bromothiazoles and iodo-N-methylimidazoles afforded the products in poor yields. The reaction of the halo-1, 3-azoles with terminal olefins was also examined.View full abstractDownload PDF (715K) -
SUGURU TAKATSUTO, NOBUO IKEKAWA1987 Volume 35 Issue 2 Pages 829-832
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSHomodolichosterone (2) and the related 2-deoxysteroids 9 and 13 were synthesized from (22R, 23R, 24S) -3β-acetoxy-22, 23-epoxy-5α-stigmastan-6-one (3). Reaction of the (22R, 23R) -epoxide 4 with phenylselenyl anion followed by heating with 30% H2O2 afforded a mixture of the allylic alcohols 5 and 6, which were then epoxidized with m-chloroperbenzoic acid. The isolated hydroxyepoxide 7 was heated with aluminum isopropoxide to yield the 3β, 22, 23-triol 9. Acetonide formation of 9 and mesylation gave the sulfonate 10, which was refluxed with lithium carbonate and dimethylformamide and then saponified to give the 3α-ol 11 and the 2, 24 (28) -diene 12. Acid hydrolysis of 11 provided the 3α, 22, 23-triol 13. Selective α-face hydroxylation of 12 with osmium tetroxide and deprotection gave homodolichosterone (2).View full abstractDownload PDF (574K) -
KAZUNOBU MIURA, KAZUYUKI SAWADAISHI, HIDEO INOUE, ETKO OHTSUKA1987 Volume 35 Issue 2 Pages 833-836
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESSFor use in automated synthesis of oligodeoxyribonucleotides, a dimer containing the triesterified internucleotide linkage and the 3 '-phosphoramidite has been prepared. 5 '-O-Dimethoxytritylthymidylyl- (3 '-5') - (o-chlorophenyl) -thymidine was converted to the 3 '- (methyl)N , N-diisopropylphosphoramidite, which has been used as a condensing unit for the synthesis of pentadecathymidylate on controlled pore glass by a deoxyribonucleic acid (DNA) synthesizer.View full abstractDownload PDF (464K) -
YOHEI KURATA, HIROSHI HIROTA, TADASHI HONDA, TAKEYOSHI TAKAHASHI1987 Volume 35 Issue 2 Pages 837-840
Published: February 25, 1987
Released on J-STAGE: October 19, 2009
JOURNAL FREE ACCESS(±) -3-Methoxy-1α, 4aβ, 8aβ-trimethyl-1, 4, 4a, 6, 7, 8, 8a, 9, 10, 10a α-decahydrophenanthrene-4, 8-dione, a tricyclic A-ring analog of quassin, was synthesized from a known tricyclic ketone through seven reaction steps, including phenylselenation in a neutral medium and the Wharton reaction.View full abstractDownload PDF (495K)