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SABURO SHIMABAYASHI, HIDEJI TANAKA, MASAYUKI NAKAGAKI
1987 年 35 巻 9 号 p.
3539-3546
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
Concentrations of phosphate ion ([Pi]
f) and calcium ion ([Ca
2+]
f), liberated from the surface of synthetic hydroxyapatite (Ca
10 (PO
4)
6 (OH)
2; HAP) during the adsorption of dodecylammonium chloride (DAC), were determined as a function of equilibrium concentration of dodecylammonium ion ([DA
+]
f). When [DA
+]
f was lower than its critical micelle concentration (cmc), [Ca
2+]
f increased with increase in [DA
+]
f owing mainly to ion-exchange between dodecylammonium ion (DA
+) and calcium ion (Ca
2+) on the surface of HAP. However, [Pi]
f decreased with increase in [Ca
2+]
f to keep the solubility product for HAP (
Ksp) constant. On the other hand, when [DA
+]
f was higher than the cmc, [Pi]
f increased with increase in [DA
+]
f due to the binding of phosphate ion (Pi) to DA
+ micelles. Cationic species (i.e., Ca
2+ and DA
+) were concomitantly liberated from the surface of HAP to maintain the electroneutrality of the surface phase. Therefore, [Ca
2+] f increased and the adsorbed amount of DA
+ (X
DA+) decreased with increase in [DA
+]
f. When CaCl
2+ was added to the solution, X
DA+ decreased with increasing concentration of added CaCl
2 owing to the competitive adsorption between DA
+ and added Ca
2+. The release of Pi was strongly depressed because of the electrostatic interaction between surface Pi and adsorbed Ca
2+, and because of the requirement of constant
Ksp in the bulk solution.
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PHILIPPE HELISSEY, HÉLÈNE PARROT-LOPEZ, JEAN RENAULT, SU ...
1987 年 35 巻 9 号 p.
3547-3557
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
8-Methoxy-2, 3, 4-trimethyl-1
H-pyrrolo [3, 2-
c] quinoline-6, 9-dione (28) and 2-methoxy-6-methyl-7, 8, 9, 10-tetrahydro-11
H-indolo [3, 2-
c] quinoline-1, 4-dione (31) can be obtained from 4-hydrazino-6-methoxy-2-methyl-5-quinolinamine (21). The synthetic method consists in creating the pyrrole or indole nucleus by applying Fischer's indole synthesis to the hydrazones (22 and 24) to give the amines (23 and 25, respectively). The catalytic dehydrogenation of 25 leads to the quinolinamine (26). The oxidation of the amines (23, 25 and 26) by Fremy's reagent (potassium nitrosodisulfonate) gives the quinones (28, 31 and 35). The nucleophilic substitution of the methoxy group by aziridine leads to 29, 33 and 36, which have moderate cytotoxic activity on L 1210 cells.
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TADAYUKI TAKEDA, KAZUYOSHI IKEDA, YOSHIHISA MIZUNO, TOHRU UEDA
1987 年 35 巻 9 号 p.
3558-3567
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
Putrescinylthymidine was prepared by the reduction of the Schiff base formed from a 2'-deoxy-5-formyluridine derivative and
N-phthaloylputrescine, followed by deprotection. The following deoxyoligonucleotides containing putrescinylthymine (T
P) were synthesized; dodecathymidylic acids containing two to four T
P residues, self-complementary decanucleotides (AAGAATTCTT) and dodecanucleotides (AGATAGCTATCT) in which T residues were partly replaced by T
P, and related oligomers. Oligonucleotides containing T
P were resistant to nuclease S1 digestion and were poor substrates to venom phosphodiesterase. The thermal stability (
Tm) of the duplex structure of oligomers containing T
P was not enhanced in spite of the expected electrostatic binding between the putrescinyl and phosphoryl residues, and was rather sequence-dependent.
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MICHIO NAMIKOSHI, HIROYUKI NAKATA, MARIKO NUNO, TAKASHI OZAWA, TAMOTSU ...
1987 年 35 巻 9 号 p.
3568-3575
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
A new homoisoflavonoid, 3'-deoxy-4-
O-methylsappanol (3, 7-dihydroxy-3- (4-hydroxybenzyl) 4-methoxychroman) was isolated from the wood of
Caesalpinia japonica SIEB.
et Zucc. (Leguminosae), together with the known compounds, sappanol, episappanol, 4-
O-methylsappanol, 4-
O-methylepisappanol, sappanones A and B, sappanchalcone, 3-deoxysappanchalcone, isoliquiritigenin, butein, brazilin and protosappanins A, B and C. None of these compounds has previously been isolated from this plant.
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YUKO TSUDA, YOSHIO OKADA, YOKO NAGAMATSU, UTAKO OKAMOTO
1987 年 35 巻 9 号 p.
3576-3584
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
Various substrate-derived chloromethyl ketones were synthesized by a conventional method for the purpose of obtaining specific and potent irreversible inhibitors for human spleen fibrinolytic proteinase (SFP) and human leukocyte elastase (LE) in order to compare the properties of SFP with those of LE. It was found that Boc-Ala-Tyr-Leu-Val-CH
2Cl among the peptide chloromethyl ketones exhibited the most effective and specific inhibition of SFP and LE. The two enzymes were inhibited by peptide chloromethyl ketones having a Val residue at the C-terminus in a similar manner, demonstrating a similarity between SFP and LE.
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NAOKI SUGIYAMA, NOBUTAKA FUJII, SUSUMU FUNAKOSHI, AKIHIRO FUNAKOSHI, K ...
1987 年 35 巻 9 号 p.
3585-3596
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
A 36-residue peptide corresponding to the entire amino acid sequence of human pancreatic polypeptide (hPP) was synthesized by the solution method. A new Asp derivative, Asp (OMen) [Men = menthyl] was employed. Seven fragments served to construct the peptide backbone of hPP and all the protecting groups employed were cleaved by 2 M trimethylsilyl trifluoromethane-sulfonate-diphenylsulfide/trifluoroacetic acid. The synthetic peptide inhibited protein secretion from rat pancreas.
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MICHIO NAMIKOSHI, TAMOTSU SAITOH
1987 年 35 巻 9 号 p.
3597-3602
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
The absolute configuration of the homoisoflavonoidal components, 4-
O-methylsappanol, 4-
O-methylepisappanol, sappanone B, 3-deoxysappanone B and 3'-deoxysappanone B, from
Caesalpinia sappan L. were determined on the basis of chemical transformations and the optical properties.
抄録全体を表示
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HITOSHI TANAKA, ICHIRO KATO, KAZUO ITO
1987 年 35 巻 9 号 p.
3603-3608
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
The condensation reaction of 3-benzyloxy-4-hydroxybenzaldehyde with 2, 3-epoxy-3- [(3, 4-dimethoxymethoxy) phenyl] -1-propanol, prepared from caffeic acid in four steps, afforded the ether (11) in good yield. Mesylation of 11 followed by treatment with potassium carbonate, provided the epoxide (13), which was converted to the debenzylation product (14) by hydrogenolysis. Compound 14 underwent cyclization with potassium carbonate to yield the
trans dioxane derivative (15). Reaction of 15 with the ylide (16) followed by hydrolysis furnished americanin A (1). Isoamericanin A (3) was similarly synthesized from another condensation product (18).
抄録全体を表示
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KIMIO FURUHATA, SHINGO SATO, KATSUKO ANAZAWA, MOTOAKI GOTO, HIROAKI TA ...
1987 年 35 巻 9 号 p.
3609-3614
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
The reactions of
N-acetylneuraminic acid with benzyl, allyl, and methyl halides in the presence of excess cesium carbonate gave the corresponding
N-acetyl-2-
O-alkyl-3, 5-dideoxy-D-
glycero-D-
galacto-2-noneno-1, 4-lactones in good yields. The structures and stereochemistry of these 1, 4-lactonic sialic acid derivatives were elucidated from the infrared and proton nuclear magnetic resonance spectra and by X-ray crystal analysis.
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MICHIO NAMIKOSHI, HIROYUKI NAKATA, TAMOTSU SAITOH
1987 年 35 巻 9 号 p.
3615-3619
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
A novel dibenzoxocin derivative, 7, 8-dihydro-10-methoxy-3, 7, 11-trihydroxy-6
H-dibenz [
b, d] -oxocin-7-methanol was isolated from Sappan Lignum, the dried heartwood of
Caesalpinia sappan L. The chemical structure was established on the basis of the spectrometric data and the chemical interrelation with protosappanin B (7, 8-dihydro-3, 7, 10, 11-tetrahydroxy-6
H-dibenz [
b, d] oxocin-7-methanol).
抄録全体を表示
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TAKABUMI NAGAI, TAKUICHI MIKI, ITSUMARO KUMADAKI
1987 年 35 巻 9 号 p.
3620-3627
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
1- (Trifluoromethyl) homoallyl alcohols, which were obtained by the ene reaction of trifluoromethyl ketones with olefins, were cyclized to 2-(trifluoromethyl) tetrahydrofurans in the presence of
p-toluenesulfonic acid, a typical Brensted acid. The ease of this cyclization depends on the substituents on the homoallyl system. The stereochemistry of the cyclization products was established by analysis of the two dimensional nuclear Overhauser effects. The stable conformations of the tetrahydrofuran compounds were estimated by means of molecular mechanics calculations of the steric energy. The observed ratio of the products was consistent with that estimated from the steric energy calculations.
抄録全体を表示
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Tozo FUJII, MASASHI OHBA, JUN SAKAGUCHI
1987 年 35 巻 9 号 p.
3628-3640
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
Alternative syntheses of the
Alangium alkaloids bearing the 9-hydroxy-10-methoxy- and 10-hydroxy-9-methoxybenzo [
a] quinolizidine skeletons (types 3 and 4) have now become feasible through generally applicable routes starting from 3-acetylpyridine. The routes include the mercuric acetate-edetic acid oxidation of the 3-acetylpyridine derivatives 8a, b or the alkaline ferricyanide oxidation of the quaternary salts (29a, b and 30a) of 3-acetylpyridine equivalents, Wolff-Kishner reduction of the acetyl group or reductive desulfurization of the thioketal group, sulfenylation dehydrosulfenylation of the lactams 15a, b, Michael reaction of the α, β-unsaturated lactams 18a, b, and hydrolysis, decarboxylation, and esterification of the Michael adducts to give 21a, b, as the main operations.
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EISUKE SATO, YOSHIYA IKEDA, YUICHI KANAOKA
1987 年 35 巻 9 号 p.
3641-3646
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
Irradiation of 2-thiopyridone (1), quinoline-2-thione (10), isoquinoline-l-thione (18h) and phthalazine-1-thione (18i) with vinyl ethers (7) gave two-fold addition products, by addition of theolefins to the C=S bond.
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MASAYUKI SATO, TAKESHI SUZUKI, HIROKO MORISAWA, SHIGEO FUJITA, NORIYOS ...
1987 年 35 巻 9 号 p.
3647-3657
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
2-Cyano-1, 2-dihydrocyclobuta [
a] naphthalene was synthesized from 2-methoxynaphthalene
via photoaddition to acrylonitrile followed by base treatment. The 4+2 cycloaddition of this compound to a variety of olefins by an application of the so-called benzocyclobutene method was examined and the regioselectivity and electron demand in these reactions were clarified. Construction of 12, 13, 14, 15, 16, 17-hexahydro-11
H-cyclopenta [
a] phenanthrene derivatives having a basic A, B-ring-aromatized steroid skeleton from this naphthocyclobutene through either inter- or intramolecular 4+2 cycloaddition is also reported.
抄録全体を表示
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MICHIYO SUZUKI, TERUYO MATSUMOTO, MASAKO OHSAKI, YOSHIKAZU KIMURA, SHI ...
1987 年 35 巻 9 号 p.
3658-3665
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
Reduction of (
R) -methyl 2, 5, 12-trihydroxy-6, 11-dioxo-1, 2, 3, 4-tetrahydronaphthacene-2-carboxylate ((
R) -5) with lithium tri-
tert-butoxyaluminum hydride in dimethyl sulfoxide was found to proceed chemoselectively, giving the corresponding alcohol ((
R) -11) in 50-55% yield. The produced (
R) -alcohol ((
R) -11) could be readily isolated as its acetonide ((
R) -12) or tert-butyldimethylsilyl ether ((
R) -13). Stereoselective C
7α -hydroxylation (the anthracycline numbering) of (
R) -13 and urethane formation produced the optically active title compounds, which are the aglycones of unnatural anthracyclines showing excellent anticancer activity.
抄録全体を表示
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OSAMU HOSHINO, KYOKO KIKUCHI, HIDETO OGOSE, BUNSUKE UMEZAWA, OICHI IIT ...
1987 年 35 巻 9 号 p.
3666-3675
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
Treatment of
o-quinol acetates (5a, b) of 1, 2, 3, 4-tetrahydro-1-phenethylisoquinolin-6-ols (6a, b) with acetic anhydride in the presence of an acid (concentrated H
2SO
4, BF
3 · Et
2O or CF
3COOH) gave 2-acetoxyhomoaporphines (4a, b) and/or aldehyde-amides (7a, b), and the ratio of the products was strongly dependent on the choice of the acid and the solvent. A mechanistic pathway is proposed.
抄録全体を表示
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TOCHIRO TATEE, KAZUHISA NARITA, SHUJI KURASHIGE, SHINJI ITO, HIROSHI M ...
1987 年 35 巻 9 号 p.
3676-3690
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
Conformationally restricted analogs of muscle-relaxant 3-amino-2-methyl-
N- (3-phenyl-5-isoxazolyl) propanamides (1) and 5- (3-aminopropylamino) -3-phenylisoxazoles (2) were prepared, and their muscle-relaxant and other pharmacological activities were tested and compared with those of the corresponding acyclic derivatives. 7- (3-Diethylamino-2-methylpropanoyl) -3-phenyl-4, 5, 6, 7-tetrahydroisoxazolo [5, 4-
b] pyridine (8) exhibited muscle-relaxant and anticonvulsant activities comparable with those of corresponding acyclic derivatives,
i.e. 3-diethylamino-2-methyl-
N- (3-phenyl-5-isoxazolyl) propanamides (1e-g), but other types of compounds showed decreased activities. The preferred conformation of the present isoxazole derivatives for muscle-relaxant activity is discussed.
7-Benzyl-6-methyl-3-phenyl-4-pyrrolidino-4, 5, 6, 7-tetrahydroisoxazolo [5, 4-
b] pyridine (3d) showed moderate central nervous system-depressant activity.
抄録全体を表示
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MASAMI SHIRATSUCHI, KIYOSHI KAWAMURA, TOSHIHIRO AKASHI, HIROSHI ISHIHA ...
1987 年 35 巻 9 号 p.
3691-3698
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
Four optical isomers of nipradilol (NIP) were prepared from (3
R) -or (3
S) -3, 4-dihydro-8-hydroxy-3-nitroxy-2
H-1-benzopyran by glycidylation and amination, and evaluated for β-blocking and vasodilating activities. The order of potency of β-blocking activity was
S, R-NIP>>
S, S-NIP > R, R-NIP>>
R, S-NIP. As regards vasodilating activity,
S, R-NIP and
R, R-NIP were more potent than
S, S-NIP and
R, S-NIP.
抄録全体を表示
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MICHIAKI TOMINAGA, HIDENORI OGAWA, EIYU YO, SHUJI YAMASHITA, YOUICHI Y ...
1987 年 35 巻 9 号 p.
3699-3704
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
Many 5- (3-amino-2-hydroxypropoxy) -3, 4-dihydro-8-hydroxy-2 (1
H) -quinolinone derivatives were synthesized and examined for positive inotropic activity on the canine heart. These compounds were prepared by the reaction of 8-alkoxy-5- (2, 3-epoxypropoxy) -2 (1
H) -quinolinone derivatives and various amines. Among them, 3, 4-dihydro-8-hydroxy-5-[3- (1, 1, 3, 3-tetramethylbutylamino) propoxy] -2 (1
H) -quinolinone hydrochloride (IIIf) was found to have potent positive inotropic activity with a relatively minor increase in heart rate.
抄録全体を表示
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YUTAKA SAIGA, IKUO IIJIMA, AKIHIKO ISHIDA, TOSHIKAZU MIYAGISHIMA, NORI ...
1987 年 35 巻 9 号 p.
3705-3712
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
Two tetrahydro-β-carboline-1-and-4-carboxylic acids (1b, c) and the corresponding hydroxymethyl derivatives (2b, c), which are positional isomers of the 3-carboxylic acid (1a) and its 3-hydroxymethyl derivative (2a), were synthesized and tested for hepatoprotective activity against carbon tetrachloride (CCl
4) -induced liver damage in mice. The hepatoprotective activity of these positional isomers decreased in the following order;1a> 1b> 1c> and 2a > 2b>2c.
The effect of alkyl substitution at the 1 position of 1a and 2a was also examined with the
cis and
trans isomers (5a, b-14a, b). Compounds with small alkyl groups such as Me and Et showed potent activity. Lengthening of the alkyl group generally caused a decrease in activity. In a series of the stereoisomers of the 3-carboxylic acids (5a, b-9a, b), the
cis isomers tend to be more active than the
trans counterparts.
抄録全体を表示
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TOSHIO MIYASE, AKIRA UENO, NOBUO TAKIZAWA, HIROMI KOBAYASHI, HIROKO OG ...
1987 年 35 巻 9 号 p.
3713-3719
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
Two new glycosides of ionone derivatives, icarisides B
3 (2) and B
4 (3), as well as a new phenylethanoid glycoside, icariside D
1 (4), and two new lignan glycosides, icarisides E
1 (12) and E
2 (13), have been isolated from
Epimedium grandiflorum MORR. var.
thunbergianum (MIQ.) NAKAI, together with eight known glycosides. The structures of the new compounds were established on the basis of chemical evidence and spectral data.
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YUKINORI MIYAICHI, YOSHITAKA IMOTO, TSUYOSHI TOMIMORI, CHUN-CHING LIN
1987 年 35 巻 9 号 p.
3720-3725
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
Four new flavanones (I-IV) and a new flavone (V) were isolated from the root of
Scutellaria indica L., together with 2 (
S) -5, 2'-dihydroxy-7, 8, 6'-trimethoxyflavanone, (±) -5, 2'-dihydroxy-6, 7, 6'-trimethoxyflavanone, 5, 7-dihydroxy-8, 2'-dimethoxy flavone, rivularin, 5, 2', 6'-trihydroxy-7, 8-dimethoxyflavone, scutevurin, 5, 7, 4'-trihydroxy-8-methoxyflavone, wogonin, alpinetin, caldamomin and wogonin 7-
O-glucuronide. Compounds I-V (Fig. 1) were identified based on spectral data and simple chemical modifications.
抄録全体を表示
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YUE-ZHONG SHU, MASAO HATTORI, TERUAKI AKAO, KYOICHI KOBASHI, KATSUMI K ...
1987 年 35 巻 9 号 p.
3726-3733
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
Paeoniflorin from peony roots was incubated with a cell suspension of
Bacteroides fragilis or
Lactobacillus brevis isolated from human intestinal flora. Paeoniflorin was converted into the 7
S and 7
R isomers of paeonimetaboline I as major metabolites, along with the 7
R and 7
S isomers of paeonimetaboline II as minor metabolites in the case of the former strain. The structures were elucidated by various spectroscopic methods, and the structure of 7
R-paeonimetaboline I was confirmed by X-ray analysis.
抄録全体を表示
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MASAHIKO CHIKUMA, YOSHITO OKABAYASHI, TERUMICHI NAKAGAWA, AIKO INOUE, ...
1987 年 35 巻 9 号 p.
3734-3739
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
A new functional resin for the selective collection of fluoride ion was prepared from anionexchange resin and lanthanum complex of Alizarin Fluorine Blue (AFB-La). The resin loaded with AFB-La was effective for the selective adsorption of fluoride ion in batch and column operations. Fluoride ion adsorbed could be eluted completely with a small volume of 1 M sodium hydroxide, and the concentration of fluoride ion thus concentrated in the eluate was determined by using an ion selective electrode. The resin could be regenerated by washing with water and used repeatedly without functional deterioration. A satisfactory result was obtained by the use of this resin in the determination of fluoride ion present at concentrations lower than that which can be determined directly by the ion selective electrode method. The interference caused by common cations and anions was not serious except for Al
3+ and Fe
3+
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MASATOSHI YAMAGUCHI, MASARU NAKAMURA
1987 年 35 巻 9 号 p.
3740-3745
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
A highly sensitive and simple high-performance liquid chromatographic method has been developed for the determination of free and total phenylacetic acid in human and rat plasma. After extraction with diethyl ether from plasma, phenylacetic acid and phenylpropionic acid (internal standard) are converted to the corresponding fluorescent derivatives by reaction with 3-bromomethyl-6, 7-dimethoxy-1-methyl-2 (1
H) -quinoxalinone in the presence of potassium hydrogen carbonate and 18-crown-6 in acetonitrile. The derivatives are separated on a reversed-phase column (Radial-Pak cartridge C
18) with aqueous 65% (v/v) methanol and detected fluorimetrically. The detection limit for phenylacetic acid is 11 pmol/ml in plasma at a signal-to-noise ratio of 5. This sensitivity permits precise determination of free and total phenylacetic acid in 50 μl of human and rat plasma. The method was applied to the determination of free and total phenylacetic acid in plasma from healthy volunteers, and control and “behavioral despair” rats.
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AKIRA SANO, MAKOTO OGAWA, SHOJI TAKITANI
1987 年 35 巻 9 号 p.
3746-3749
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
A fluorometric method for the determination of phenylpyruvic acid (PPA) has been established. Benzaldehyde formed from PPA by alkaline decomposition is quantified by means of its fluorogenic reaction with 1, 4-dimethyl-3-carbamoylpyridinium chloride. PPA can be determined in the range of 0.1-3 nmol/50 μl with the relative standard deviation of 4.0-4.1%. About 70% recovery was obtained when a urine sample (0.1 ml) added with 5 nmol of PPA was extracted and then determined by the proposed method. The method should be useful for the biochemical diagnosis of phenylketonuria.
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KEN'ICHI HAGIWARA, HIROSHI NAKAMURA, TERUMI NAKAJIMA
1987 年 35 巻 9 号 p.
3750-3756
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
The fluorescent Kashland reagent, 2-carboxy-1-hydroxy-4-naphthylmethyldimethylsulfonium chloride (FKR), has three different functions : a) a phenolic hydroxy group
ortho to carboxy group to chelate metal ions; b) a naphthyl moiety to produce fluorescence; and c) a Koshland reagent-type sulfonium chloride group to modify tryptophyl residues selectively in a peptide chain. Three procedures, methods I, II and III, using this reagent for the selective isolation of tryptophan-containing peptides from a protein digest were investigated. We selected lysozyme and carboxymethylated lysozyme as model proteins. In method I, lysozyme was labeled with FKR prior to the enzyme digestion, and the labeled protein was purified by gel permeation chromatography to remove the by-product formed from the reagent, then digested with protease. In method II, the protein (carboxymethylated lysozyme) was similarly labeled with the reagent, and the labeled protein was recovered as a precipitate by adding ethanol, leaving the excess reagent in the supernatant. The labeled protein was digested with protease. In method III, the protein was digested by protease before treatment with the reagent, and the by-product was removed by extraction with benzene. When the digests obtained by these procedures were applied to a Chelating Sepharose 6B column (Fe
3+ or Al
3+ form), FKR-labeled tryptophan-containing peptides were selectively adsorbed on the column owing to its chelating ability and could be eluted with 50 mM ethylenediaminetetraacetic acid. The final purification of these peptides was performed by reversed-phase high performance liquid chromatography on an octadecylsilane column in all cases.
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TAKASHI ABIKO, HIROSHI SEKINO
1987 年 35 巻 9 号 p.
3757-3765
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
Thymosin β
4 fragment 16-38, H-Lys-Leu-Lys-Lys-Thr-Glu-Thr-Gln-Glu-Lys-Asn-Pro-Leu-Pro-Ser-Lys-Glu-Thr-Ile-Glu-Gln-Glu-Lys-OH, was synthesized by a solution method, by assembling five peptide fragments followed by deprotection with 1 M trifluoromethanesulfonic acid-thioanisole in trifluoroacetic acid. The synthetic tricosapeptide was tested for effect on the impaired blastogenic response of phytohemagglutinin-stimulated T-lymphocytes of a uremic patient with pneumonia. The synthetic tricosapeptide was found to have restoring activity, which was approximately equal in potency to that of our synthetic deacetyl-thymosin β
4.
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MASAYOSHI YAMAGUCHI, HIROSUKE SHIBANO
1987 年 35 巻 9 号 p.
3766-3770
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
The effect of calcium-binding protein (CaBP) isolated from rat liver cytosol on the Ca
2+-induced increase in succinate dehydrogenase activity of rat liver mitochondria was investigated. The liver mitochondrial succinate dehydrogenase activity was significantly increased by addition of Ca
2+ in the range of 1.0-50 μM. Of various other metals (25 μM) tested, addition of Hg
2+, Zn
2+ and Cd2 + caused a significant decrease in succinate dehydrogenase activity of the hepatic mitochondria, while Mg
2+, Mn
2+ and Sr
2+ had no effect;the increase in the enzyme activity was specific for Ca
2+. This Ca
2+-induced increase in the mitochondrial succinate dehydrogenase activity was completely blocked by the presence of ruthenium red (10 and 50 μM), an inhibitor of mitochondrial Ca
2+ uptake, indicating that Ca
2+ was transported into the mitochondria and activated the enzyme there. In the presence of more than 7.0 μM CaBP, the Ca
2+ (10 μM) -induced increase in succinate dehydrogenase activity was completely reversed, but 1.4 μM CaBP had no effect on this increase. CaBP itself (15 μM) did not have an inhibitory effect on the basal activity of succinate dehydrogenase. The present results suggest that CaBP regulates the increase in succinate dehydrogenase activity by blocking Ca
2+ transport into the hepatic mitochondria of rats.
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YUKI SAKAI, YUKIKO SUMIDA, MASAAKI TSUDA, SUMIO SHINODA, TOMOFUSA TSUC ...
1987 年 35 巻 9 号 p.
3771-3776
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
The properties and roles of adenosine triphosphate (ATP) -hydrolyzing enzymes in the membrane of
Vibrio parahaemolyticus were investigated. At least two (perhaps three) types of ATP-hydrolyzing enzyme was present in everted membrane vesicles. The adenosine triphosphatase (ATPase) activity of one of the enzymes was sensitive to dicyclohexylcarbodiimide and the activity was lost when the membranes were washed with buffer containing ethylenediaminetetraacetic acid. This enzyme seems to be an H
+-translocating ATPase. The other ATP-hydrolyzing activity was due to a tightly bound enzyme that could not be removed from the membranes by the washing. This enzyme required higher concentrations of Mg
2+ (10 to 20 mM) and Cl
- (100 mM) for maximal activity. Zn
2+ strongly inhibited the activity. The substrate specificity of this enzyme activity showed that it was a 5 '-nucleotidase.
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AKIKO KANAMORI, NOBUKO SENO, ISAMU MATSUMOTO
1987 年 35 巻 9 号 p.
3777-3783
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
For high-performance liquid affinity chromatography (HPLAC) of trypsin-family enzymes, two kinds of adsorbents (I and II) were prepared by convenient procedures using
m-aminobenzamidine (ABA) and TSKgel G3000PW, a carrier for high-performance gel chromatography. For adsorbent I, ABA was immobilized on succinyl-TSKgel G3000PW, which was prepared by successive epoxy-activation, amination and succinylation of TSKgel G3000PW with the aid of
N-ethoxycarbonyl-2-ethoxy-1, 2-dihydroquinoline (about 16 μmol ABA/g wet gel, about 80% yield). For adsorbent II, ABA was immobilized on formyl-carrier, which was prepared by successive epoxy-activation, hydrolysis and periodate-oxidation of TSKgel G3000PW through reductive amination with sodium cyanoborohydride (19 μmol ABA/g wet gel, 98% yield). In the case of HPLAC on adsorbent I, bovine and
Streptomyces griseus trypsins were eluted at 12 and 19 min, respectively, whereas the enzymes were retained on adsorbent II and were recovered efficiently with eluting buffer containing 6-aminohexanoic acid. The results indicate that adsorbent I is useful for rapid analysis of the enzymes and adsorbent II for the preparation of the enzymes.
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SATOSHI MATSUMOTO, YOSHIE HAYASHI, MITSURU HASHIDA, HITOSHI SEZAKI
1987 年 35 巻 9 号 p.
3784-3791
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
Cellular interaction and
in vitro antitumor activities of lipophilic prodrugs of mitomycin C (MMC) were studied in order to clarify their mode of action. Five lipophilic derivatives with various lipophilic promoieties (benzylcarbonyl, benzyloxycarbonyl, pentyloxycarbonyl, nonyloxycarbonyl, and cholesteryloxycarbonyl groups) were tested. All the derivatives except for cholesteryloxycarbonyl MMC were converted to MMC in the supernatant of tumor cell homogenate.
Lipophilic derivatives, especially nonyloxycarbonyl MMC and cholesteryloxycarbonyl MMC, associated with Ehrlich ascites carcinoma (EAC) cells more readily than MMC. While the association percentage remained almost constant during the course of incubation at 4 °C, it increased with incubation period at 37 °C, suggesting metabolic consumption of lipophilic derivatives in the tumor cells. Association percentages of derivatives at 4 °C were closely correlated to their partition coefficients between chloroform and water. The apparent distribution ratio of benzyloxycarbonyl MMC between EAC cells and the incubation medium also correlated with their volume ratio. These results suggested that lipophilic derivatives were incorporated into tumor cells through partition equilibrium between lipid components of tumor cells and the medium.
In vitro antitumor activities of lipophilic MMC derivatives were studied using EAC and L1210 leukemia cell culture. In the continuous exposure experiment, lipophilic derivatives which were converted to MMC in tumor cells showed equal or somewhat lower growth inhibitory activity as compared with MMC. In the case of 1 h or 5 min exposure, nonyloxycarbonyl MMC was more active than MMC, indicating that the growth-inhibitory effects of lipophilic derivatives are closely related to both cellular interaction and conversion rate to MMC.
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SATOSHI MATSUMOTO, TSUNEHIKO SHIGEOKA, YOSHINOBU TAKAKURA, MITSURU HAS ...
1987 年 35 巻 9 号 p.
3792-3799
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
L1210 mouse leukemia cell lines resistant to mitomycin C (MMC) were established by repeated continuous exposure of parental L1210 leukemia cells to MMC
in vitro. The established cell lines showed 13-fold or more resistance to MMC compared with the parental cell line. A macromolecular prodrug of MMC, MMC-dextran conjugate with cationic charge (MMC-D
cat.), and lipophilic MMC prodrugs were assessed for ability to circumvent the resistance of tumor cells against MMC. Association of MMC and its prodrugs with resistant cell lines was similar to that with the parental cell line. Higher cellular association of drugs was observed with increase of the molecular weight of MMC-D and with increase of the partition coefficient of lipophilic MMC prodrugs.
In vitro antitumor activities of MMC prodrugs against resistant cell lines were evaluated by determining cell number after cultivation for 3 or 4 d with the agents. In the continuous exposure experiment, the degrees of resistance to most prodrugs were almost the same as that to MMC. On the other hand, MMC-D
cat. showed higher activity against parental L1210 cells but lower activity against resistant cells than MMC in the 1 h exposure experiment. In the case of lipophilic MMC prodrugs, nonyloxycarbonyl MMC showed higher activity against both parental and resistant cells compared with MMC. The degree of resistance to nonyloxycarbonyl MMC was one-fifth of that to MMC. Thus, it may be possible to attack the drug-resistance problem by means of the prodrug approach.
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HIROFUMI TAKEUCHI, TETSUROU HANDA, YOSHIAKI KAWASHIMA
1987 年 35 巻 9 号 p.
3800-3806
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
Spherical solid dispersion particles of tolbutamide were prepared by spray-drying a diluted ammonia solution of the drug with additives. Enteric coating polymers (Eudragit
® L100-55, hydroxypropyl methylcellulose phthalate) and colloidal silica (Aerosil
®) were useful as additives for the solid dispersions. Most of the tolbutamide was dispersed in the amorphous state in the solid dispersion particles when the drug and the additive were formulated in the ratio of 1 : 1. It was a characteristic of the spray-dried solid dispersions that the additive content was smaller than that of dispersions prepared by conventional solvent evaporation or by a grinding method. The drug dissolution
in vitro was investigated using the disintegration solution No. 2 (pH 6.8) specified in JP X. The dissolution rate from the solid dispersions was markedly improved compared with that from the original or spray-dried drug powder. The rapid dissolution rate from the solid dispersion with enteric coating polymers was attributed to improved wettability and rapid dissolution of the polymer, while that from the dispersion with colloidal silica was found to have a close relationship with the drug crystallinity as well as the wettability.
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TOSHIAKI NISHIHATA, KEIKO KOTERA, YOHKO NAKANO, MASARU YAMAZAKI
1987 年 35 巻 9 号 p.
3807-3812
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
Poor penetration of diclofenac through
in vitro rat dorsal skin including subcutaneous tissue was observed. The poor penetration of diclofenac seemed to be predominantly due to the poor permeability of the stratum corneum. Hydrogenated soya phospholipids (phospholipid) in aqueous gel form increased the penetration of diclofenac in the
in vitro study, by increasing diclofenac transport through the stratum corneum. In the
in vivo percutaneous absorption of diclofenac, the presence of phospholipid in aqueous gel form increased both plasma diclofenac concentration and diclofenac accumulation in the dorsal skin tissue, including subcutaneous tissue. Since a marked accumulation of diclofenac in the subcutaneous tissue after application of the aqueous gel was observed both
in vivo and
in vitro, percutaneous application of diclofenac in the aqueous gel form, prepared with phospholipid, may be available for topical treatment rather than for systemic treatment.
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KEN MASUMOTO, KUMIKO YAMASHITA, AKIYOSHI YOSHIDA, SHIN'ICHI HAYASHI, Y ...
1987 年 35 巻 9 号 p.
3813-3821
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
A method for the production of water-insoluble glucan was developed by utilizing the extracellular glucosyltransferase present in the culture fluid of
Streptococcus mutans, and some physicochemical properties of the glucan powder were investigated.
Streptococcus mutans was cultured in brain heart infusion (BHI) medium. The growth phase shifted to the logarithmic phase and the stationary phase at 6 and 14h after the inoculation of the preculture into BHI medium, respectively. The doubling time was about 180 min.
Water-insoluble glucan was produced by incubation of the cell-free supernatant of the culture fluid with sucrose added as a substrate. The amount of water-insoluble glucan produced was affected by the concentration of substrate, temperature and pH; the optimum values of these factors were 15% (w/w), 37 °C and 7.5, respectively. By gas-liquid chromatographic analysis of the methylated water-insoluble glucan, the glucan chain was found to consist of 60% of α-1, 3-and 20% of α-1, 6-D-glucosidic bonds. The molar percent of each type of linkage was not affected by the pH of the reaction mixture but was affected by the incubation temperature. Among 8 strains examined, OMZ-176 and 6715 showed the best production of water-insoluble glucan. No peak was observed in the powder X-ray diffraction pattern of the freeze-dried glucan, suggesting that it is an amorphous powder. The hygroscopicity of the glucan powder was similar to that of corn starch. A rheological study showed that a dispersion of the glucan had non-Newtonian and shear-thinning behavior.
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MAKOTO HAGA, TAKESADA SHIMURA, TOHRU NAKAMURA, YURIKO KATO, YASUO SUZU ...
1987 年 35 巻 9 号 p.
3822-3830
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
The effect of ultrasonic irradiation on the dissociation of antigen-antibody complexes was studied. Among three frequencies tested, 28 kHz ultrasound gave a relatively high percent dissociation with the lowest decrease of immune reactivity. When dissolved antigen-antibody complexes were exposed to the ultrasonic irradiation no dissociation was observed, while antigen-antibody complexes were significantly dissociated by ultrasound when the antibodies had been immobilized on CH-Sepharose 4B. The immune reactivity of immobilized antibody decreased by 8% during irradiation with 28 kHz ultrasound (0.83 W/cm
2) for 20 min but no further decrease was observed after another 70 min of sonication. No degradation of antibody was observed after exposure to the ultrasound for 120 min. The dissociating effect of the ultrasound was applied to a homogeneous enzyme immunoassay system with the use of EMIT digoxin assay and anti-digoxin antibody-immobilized CH-Sepharose 4B gel. It was found that the change of absorbance at 340 nm increased with the concentration of non-labeled antigen in the presence of ultrasound. The feasibility of repeated application of immobilized antibodies in conjunction with ultrasonic dissociation as an immunosensor system is discussed.
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YUKIHISA KURONO, KINYA KAMIYA, TOMONARI KUWAYAMA, YASUHIRO JINNO, TAMO ...
1987 年 35 巻 9 号 p.
3831-3837
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
The oxazolidine ring-opening and ring-closing reactions of mexazolam, cloxazolam, haloxazolam, and flutazolam were investigated by a pH-jump method, similarly to the case of oxazolam reported previously [Kurono
et al., Chem. Pharm. Bull., 33, 1633 (1985)]. Mexazolam exists essentially as a single isomer, either
cis or
trans (referring to the 3-methyl group and 11b- (2'-chlorophenyl) group), differently from the case of oxazolam (
cis isomer/
trans isomer ratio for oxazolam _??_ 1 : 1). Over the pH range of 1-13, the pH-rate profiles show two step reactions. For interpretation of these profiles, we propose a reaction mechanism including an intermediate, detected by the kinetic method, between the iminium structure (oxazolidine ring-opened form) and the ring-closed form. These kinetic properties of mexazolam differ from those of other benzodiazepinooxazoles, and the difference is caused by the presence of the 3-methyl group rather than the 2'-chlorine atom. The intrinsic rate constants of mexazolam, its 2'-chlorine deficient analog (3-methyl compound), cloxazolam, haloxazolam, and flutazolam were determined according to the appropriate reaction schemes.
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SHOJI KOJIMA, MORIO KIYOZUMI, TOSHIYA HONDA, YOSHINOBU SENBA, KAZUYOSH ...
1987 年 35 巻 9 号 p.
3838-3844
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
The effects of various chelating agents, sodium
N-benzyl-D-glucamine dithiocarbamate (NBGDTC), sodium
N-p-methylbenzyl-D-glucamine dithiocarbamate (NMBGDTC), and sodium
N-p-isopropylbenzyl-D-glucamine dithiocarbamate (NPBGDTC), which were newly synthesized, sodium
N-methyl-D-glucamine dithiocarbamate (NMGDTC), diethyldithiocarbamate (DEDTC), dihydroxyethyldithiocarbamate (DHEDTC), and dicarboxymethyldithiocarbamate (DCMDTC), on the distribution and excretion of cadmium in rats were compared at 30 min and 24 h following cadmium injection. At 30 min after cadmium administration, these chelating agents all significantly enhanced the biliary excretion of cadmium, and at 24 h after cadmium injection, the chelating agents other than DEDTC and DCMDTC significantly enhanced the biliary excretion of the metal. The effects of NBGDTC, NMBGDTC, and NPBGDTC on the biliary excretion of cadmium were much larger than those of the other chelating agents. The urinary excretion of cadmium was increased by the chelating agents other than DEDTC and NPBGDTC. These chelating agents were effective in mobilizing cadmium from the liver, kidney, and pancreas at 30 min after treatment with cadmium. At both 30 min and 24 h after treatment with cadmium, NBGDTC, NMBGDTC, and NPBGDTC effectively depressed cadmium content in the liver without the mobilization of cadmium to the kidney. The chelating agents other than DEDTC did not result in the redistribution of cadmium to the brain, testes, lung, and heart. These results show that the injection of NBGDTC, NMBGDTC, or NPBGDTC at both 30 min and 24 h after treatment with cadmium can much more effectively mobilize cadmium from the body, mainly through the bile, without redistribution of cadmium to other tissues, such as brain, testes, lung, and heart, when compared with injection of other chelating agents. Furthermore, the pattern of mobilization and excretion of cadmium following treatment with each chelating agent was related to the organic/aqueous partition coefficient of each dithiocarbamate-cadmium complex.
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YOSHIHISA MORIMOTO, KAZUO ACHIWA
1987 年 35 巻 9 号 p.
3845-3849
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
The asymmetric synthesis of (-) - and (+) -cucurbitine was carried out by a method involving 1, 3-dipolar cycloaddition of the intermediary azomethine ylide and pig liver esterase (PLE) - catalyzed hydrolysis. The thio analogue, (-) -3-aminotetrahydrothiophene-3-carboxylic acid, was also synthesized.
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RYUJI YONEDA, HIDEKI HISAKAWA, SHINYA HARUSAWA, TAKUSHI KURIHARA
1987 年 35 巻 9 号 p.
3850-3852
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
A direct conversion of a variety of aldehydes to the corresponding
tert-butyldimethylsilyl protected cyanohydrins is described, by using
tert-butyldimethylsilyl chloride and lithium cyanide.
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NAOKI TENO, SATOSHI TSUBOI, YOSHIO OKADA, NORIO ITOH, HIROSHI OKAMOTO
1987 年 35 巻 9 号 p.
3853-3858
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
The tridecapeptide corresponding to the sequence 165-177 of T-kininogen (tryptic peptide) (I) containing Gln-Val-Val-Ala-Gly sequence was synthesized by a conventional solution method and its effect on thiol proteinase was examined. Although Z-Gln-Val-Val-Ala-Gly-OMe showed inhibitory activity towards papain and protective activity against T-kininogen-induced inhibition of papain, the tryptic peptide obtained did not exhibit any effect on thiol proteinase. In order to study the relationship between structure and effect on thiol proteinase, several compounds (II-VI) modified with various groups at the N-terminus of the Gln-Val-Val-Ala-Gly sequence were synthesized. Peptides V and VI, which have an aromatic ring at the N-terminus, exhibited weak inhibitory and significant protective activities. A small peptide such as Gln-Val-Val-Ala-Gly might be better able to approach papain than the tryptic peptide (I), and the aromatic ring associated with Gln-Val-Val-Ala-Gly at the N-terminus apparently strengthened the binding ability of the peptide to papain.
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KENICHI AKAJI, MOTOYOSHI NOMIZU, KAZUHIDE WATANABE, SUSUMU FUNAKOSHI, ...
1987 年 35 巻 9 号 p.
3859-3865
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
A 41-residue peptide corresponding to the entire amino acid sequence of ovine corticotropin releasing factor (oCRF) was synthesized by assembling ten peptide fragments of established purity, followed by hard-acid deprotection with 1
M trimethylsilyl trifluoromethanesulfonate in trifluoroacetic acid. β-Cycloheptylaspartate was employed to minimize base-catalyzed succinimide formation. When tested by
in vivo assay, synthetic oCRF was as active as synthetic hCRF in terms of ability to release immunoreactive corticotropin.
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KENZO HARIMAYA, TAMIKO OHKURA, JI-FU GAO, YOICHI IITAKA, EIJI OSAWA, S ...
1987 年 35 巻 9 号 p.
3866-3869
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
Molecular mechanics calculations of flexible germacrenediones, especially curdione (1) and neocurdione (2), isolated from
Curcuma wenyujin (Zingiberaceae), were used to identify the stable conformations among forty-eight conformers for each compound. The calculated ratios (70 : 30 for 1 and 68 : 32 for 2) of conformations of
anti and
syn type (C (5) = O/C (10) -CH
3) are in reasonably good accordance with the ratios (5 : 1 for 1 and 2 : 1 for 2) which were estimated from lowtemperature nuclear magnetic resonance (NMR) measurements. The populations of the intermediate conformations considered to be involved in the biomimetic conversions from 1 to curcumol (3) and curcumalactone (4) were found to be 11.9% of
syn type and 1.0% of
anti type, respectively.
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TOSHIHIRO FUJIOKA, YUKIKO IWASE, HIKARU OKABE, KUNIHIDE MIHASHI, TATSU ...
1987 年 35 巻 9 号 p.
3870-3873
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
From the less polar saponin fraction of the dried herb of
Actinostemma lobatum MAXIM. (Cucurbitaceae), two new dammarane-type triterpene glycosides, actinostemmosides G and H, were isolated. The structures of actinostemmosides G and H were elucidated mainly on the basis of spectral evidence as (20S) -3β, 6α, 7β, 20, 27-ptentahydroxy-dammar-24-ene 20-
O-β-D-glucopyranoside and (20S) -3β, 7β, 18, 20, 27-pentahydroxy-dammar-24-ene 20, 27-bis-
O-β-D-glucopyranoside, respectively.
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KIMIHIRO KANEMITSU, YOSHISUKE TSUDA, MOHAMMED EKRAMUL HAQUE, KOJI TSUB ...
1987 年 35 巻 9 号 p.
3874-3879
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
Treatment of methyl 2-
O-acetyl-3, 4-
O-thiocarbonyl-β-L-arabinopyranoside with tributyltin hydride produced seven compounds, depending on the reaction conditions : the deoxy derivatives (2 and 3), the methylidene derivative (4), the carbonate (5), the
O,
S-rearrangement products (7 and 8), and the 4-deoxy acetyl migration product (9). Their structures were determined by spectroscopic and chemical means, and their formation mechanisms are discussed.
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NOBUTAKA FUJII, AKIRA OTAKA, NAOKI SUGIYAMA, MIKA HATANO, HARUAKI YAJI ...
1987 年 35 巻 9 号 p.
3880-3883
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
Trimethylsilyl bromide (TMSBr) in trifluoroacetic acid (TFA) was found to have the ability to cleave benzyl-type protecting groups,
i.e., benzyloxycarbonyl (Z), benzyl (O-Bzl) and
p-methoxybenzyl (S-MBzl). The reaction was best accelerated by addition of thioanisole, compared with other soft nucleophiles so far examined. The rate of the cleavage reaction with TMSBr/TFA was judged to be somewhat slower than that with trimethylsilyl trifluoromethanesulfonate/TFA. However, TMSBr/TFA reduced Met (O) efficiently and gave almost no side reaction of Asp (succinimide formation). This deprotecting procedure was applied to the synthesis of human gastrin-releasing peptide.
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KAZUO NEGISHI, MASUMI KAWAKAMI, KIKUKO KAYASUGA, JUNICHI ODO, HIKOYA H ...
1987 年 35 巻 9 号 p.
3884-3887
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
N4-Aminocytidine, a mutagenic nucleoside, was obtained as crystals on reaction of cytidine with a reagent mixture consisting of hydrazine, bisulfite and phosphate buffer at pH 7. The product can be precipitated directly from the reaction mixture, and therefore the procedure is suitable for preparing
N4-aminocytidine in large quantities.
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HIDEO INOUE, TAKEO MORI, SHOJI SHIBATA, HIROSHI SAITO
1987 年 35 巻 9 号 p.
3888-3893
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
Glycyrrhetinic acid (Ia) and fourteen derivatives of glycyrrhetinic acid were examined to estimate the antinociceptive activity (tests on writhing and vascular permeability induced by 0.7% acetic acid) and anti-type IV allergic effects in mice. Among them, three dihemiphthalate compounds (IIf, IIIc, IVc) derived from, deoxoglycyrrhetol (IIa), showed strong inhibition of writhing and dye leakage at a dose of 6.25 mg/kg (
p. o.) and type IV allergy at 25 mg/kg (i. p.). Among the hemisuccinate compounds, Ib, IIb and IIIb, had significant inhibitory effects on both writhing and vascular permeability, whereas IIc and IVb inhibited only one of the two responses, at 200 mg/kg (
p. o.). Four of the hemisuccinate compounds (IIb, c, IIIb, IVb) suppressed type IV allergy at 100 mg/kg (
i. p.). Glycyrrhetinic acid (Ia) and deoxoglycyrrhetol (IIa) showed no detectable inhibition in the screening tests at doses of less than 200 mg/kg (i. p.).
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SHOICHIRO OZAKI, TOSHIO NAGASE, HIROFUMI TAMAI, HARUKI MORI, AKIO HOSH ...
1987 年 35 巻 9 号 p.
3894-3897
発行日: 1987/09/25
公開日: 2009/10/19
ジャーナル
フリー
For the purpose of diminishing the toxicity of 5-fluorouracil (1) and obtaining biologically active derivatives of 1 suitable for oral administration, alkylthiomethyl, alkylsulfinylmethyl, alkylsulfonylmethyl, and acylthiomethyl groups were introduced at the 1- and 3-positions of 1. The antitumor activity of these synthetic compounds was tested against L1210 leukemia in mice. 1-Alkylthiomethyl-5-fluorouracils showed weak antitumor activity at a high dose (300 mg/kg).
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