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海宝 輝光, 伊藤 喬, 山口 健太郎, 大沢 昭緒
1990 年 38 巻 12 号 p.
3191-3194
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
The potential energy surfaces of the degradations of 1, 2, 3, 4-tetrazine (1a) to C
2H
2+2N
2 or 2HCN+N
2 were obtained from semiempirical molecular orbital calculations using the AM1 method. It was suggested that the degradation of 1a to 2HCN+N
2 occurred in a concerted fachion, whereas the decomposition to C
2H
2+2N
2 was demonstrated to proceed via a stepwise pathway. The latter process was more favorable than the former, and was analogous to the degradation process of 2-phenyl-2H-[1, 2, 3]triazolo[4, 5-e][1, 2, 3, 4]tetrazine (3), which is the only example of 1, 2, 3, 4-tetrazine ring.
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郭 悦雄, 呉 増榮, 鄭 明珠, 王 瑜
1990 年 38 巻 12 号 p.
3195-3201
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
Extracts of the heatwood of Juniperus formosana HAYATA were found to contain the known constituents β-sitosterol, α-cedrol, 4-ketocedrol, 3βhydroxycedrol, isocedrolic acid, δ-cadinol, cadin-8-en-10-ol, clovandiol, sugiol, Δ
5-dehydrosugiol, totarol, 7-oxototarol, cryptojaponol, emodin, and methyl α-conidendral, together with five new compounds, 7α-methoxydeoxocryptojaponol, suginal, detetrahydroconidendrin, formosanol, and junipediol. In addition, 7β-hydroxydeoxocryptojaponol was obtained (first isolation as a natural product). Junipediol has a novel sesquiterpene skeleton which was elucidated by X-ray analysis.
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斉藤 博満, 佐藤 章, 芦沢 忠, 森本 眞, 平田 正
1990 年 38 巻 12 号 p.
3202-3210
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
O-Demethyl-DX-52-1 (3a) was prepared from quinocarcin (1) in two steps (cyanation and O-demethylation). Upon treatment with Fremy's salt, 3a and its esters 3b, 3c afforded the desired quinone4-6 in good yields. Various substituted quinones 12-37, 47-50 were prepared from 4-6 by Thiele acetylation followed by hydrolysis of acetates and halogenation, by direct addition of amine, alcohol and mercaptan, and by epoxidation and subsequent opening of the epoxide ring with aniline. The quinonemonoketals 39b and 40 were obtained from the corresponding methoxyphenols 7b and 38b. Addition of hydroxylamine gave the quinoneoxime 44 regiospecifically. The antitumor activity of the bis-methylthioquinone (37) among the various derivatives was the most promising.
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宮本 皓之, 松本 純一
1990 年 38 巻 12 号 p.
3211-3217
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
A new and convenient synthesis of 6-fluoro-4(1H)-oxopyrido[2, 3-c]pyridazine-3-carboxylate derizatives was achieved. One-pot reactions of ethyl 2-diazo-2-(6-chloro- and 6-tolylthio-5-fluoro-2-halonicotinoyl)acetates (9a and 9b, c) with tri-n-butylphosphine or tricyclohexylphosphine gave ethyl 7-chloro- and 7-tolylthio-6-fluoro-4(1H)-oxopyrido[2, 3-c]pyridazine-3-carboxylates (12a and 12b), respectively. The reaction of 9a-c with triphenylphosphine gave {[1-ethoxycarbonyl-1-(6-chloro- and 6-tolylthio-5-fluoro-2-halonicotinoyl)methylene]hydrazono}triphenylphosphoranes (10a-c, R=Ph), which were hydrolyzed to the corresponding hydrazones 11a-c. Intramolecular cyclization of the hydrazones 11b and 11c furnished an alternative and efficient synthesis of 12b. Possible mechanisms for the reaction of 9 leading to 12 are discussed.
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崔 承彬, 手塚 康弘, 菊池 徹, 中野 洋文, 玉沖 達也, 朴 鐘喜
1990 年 38 巻 12 号 p.
3218-3225
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
A new γ-lactone derivative named davallialactone (4) and the 7-O-β-D-glucuronide of (±)-eriodictyol (5a) have been isolated from Davallia mariesii MOORE along with caffeic acid (1), 4-O-β-D-glucopyranosylcaffeic acid (2) and 4-O-β-D-glucopyranosyl-p-coumaric acid (3). The structures of the new compounds were determined by chemical and spectroscopic methods including two-dimensional nuclear magnetic resonance (2D NMR) techniques, especially
1H-detected heteronuclear multiple-bond multiple-quantum coherence and long-range C-H J-resolved 2D NMR techniques.
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神谷 庄造, 山口 健太郎, 宮原 誠, 宮田 直樹
1990 年 38 巻 12 号 p.
3226-3229
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
1-Aryl-1-nitroso-3-(2-pyridylmethyl)ureas cyclize to 2-aryl-5-(2-pyridyl)-2, 4-dihydro-1, 2, 4-triazol-3-ones on being heated in acetone, chloroform or ether, in 59-86% yields. Their structures were condirmed by X-ray crystallography, and the molecular geometry of the 2, 4-dihydro-1, 2, 4-triazol-3-one ring is discussed in comparison with those of related zwitterionic ring compounds. Similar treatment of the corresponding 4-pyridyl derivative, 1-aryl-1-nitroso-3-(4-pyridylmethyl)urea did not give any cyclized compound, and 1, 3-bis(4-pyridylmethyl)urea was obtained in 60% yield. Mechanisms are proposed for the above reactions.
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西田 まゆみ, 伊関 克彦, 柴崎 正勝, 池上 四郎
1990 年 38 巻 12 号 p.
3230-3237
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
The first asymmetric total synthesis of (+)-hirsutic acid has been accomplished in a highly stereocontrolled manner, including a novel method for the preparation of (1S, 5R, 6S)-6-hydroxy-cis-bicyclo[3.3.0]octan-3-one and a stereospecific Simmons-Smith reaction controlled by the participation of a relatively remote hydroxyl group.
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Bruno BOTTA, Paolo IACOMACCI, Vittorio VINCIGUERRA, Giuliano Delle MON ...
1990 年 38 巻 12 号 p.
3238-3241
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
The BF
3 catalyzed dimerization of (E)-3, 4-dimethoxycinnamic acid methyl ester offers a route to aryltetralin lignans. The mechanism of the reaction is discussed.
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片桐 信弥, 伊勢 秀也, 渡辺 信久, 金子 主税
1990 年 38 巻 12 号 p.
3242-3248
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
Dialkyl 1, 3-dithiethan- and 1, 3-dithiolan-2-ylidenemalonate S-oxides have been found to serve as new dienophiles for Diels-Alder reaction with cyclopentadiene. Furthermore, since the adducts thus obtained were transformed to dialkyl 3-oxobicyclo[2.2.1]heptane-2, 2-dicarboxylates, these dienophiles behaved as dialkoxycarbonylketene equivalents.Synthesis of di-l-methyl [1R and 1S]-1, 3-dithiethan-2-ylidenemalonate 1-oxides and their successful use in asymmetric Diels-Alder rections with cyclopentadiene are also described.
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中林 和則, 坪井 諭志, 藤本 泰造, 岡田 芳男, 永松 陽子, 山本 順一郎
1990 年 38 巻 12 号 p.
3249-3252
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
H-Ser-Pro-Val-Thr-Leu-Asp-Leu-Arg-Tyr-OMe, corresponding to the sequence 41-49 of eglin c, inhibited human leukocyte cathepsin G and α-chymotrypsin. In order to gain further insight into the relationship between the structure and the inhibitory activity against cathepsin G and α-chymotrypsin, peptide fragments related to the above nonapeptide were synthesized by a conventional solution method and their inhibitory activities were examined. The smallest peptide which exhibited inhibitory effects on the above envymes was H-Pro-Val-Thr-Leu-OMe, corresponding to the sequence 42-45 of eglin c.
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浜道 則光, 宮坂 貞
1990 年 38 巻 12 号 p.
3253-3256
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
Substituent and solvent effects on the tautomeric equilibration (E/Z) of α-(N-alkyl and -arylaminomethylene)-9-(methoxymethyl)-9H-purine-6-acetonitriles (3a-q) have been studied by means of proton nuclear magnetic resonance spectroscopy in protic and aprotic solvents at 25°C. In chloroform-d these compounda (3a-q) exist mainly as the E-form. On the other hand, in methanol-d
4 or dimethylsulfoxide-d
6 the alkylamines (3a-c), phenylamine (3e), meta- or para-substituted phenylamines (3f-j) and 2, 6-disubstituted phenylamines (3p and q) exist mainly as the Z-form, while the trityl compound (3d), and ortho-substituted compounds (3k-o) showed a predominance of the E-form.
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三木 康義, 八軒 浩子, 野口 晃司, 大田 真由美, 中野 彰子, 高橋 紘一, 竹村 庄司
1990 年 38 巻 12 号 p.
3257-3260
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
The synthesis of two kinds of propranolol analogues, A and B, with a rigid skeleton was investigated. The compounds were designed to help identify the conformation involved in β-adrenergic receptor-propranolol interaction. The key intermediate, 2-hydroxy·2, 3-dihydronaphtho[1, 8-bc]pyran (5), was obtained starting from acenaphthenone (1). On sequential dehydration, hydroboration, and oxidation, 5 gave 2, 3-dihydronaphtho[1, 8-bc]pyran-3-one (8), which was converted to compound A. Compound 5 was also derived to 2-formyl-2, 3-dihydronaphtho[1, 8-bc]pyran (13) via the 2-vinyl compound (12). Condensation of nitromethane with 13 followed by reduction and alkylation produced the desired compound B. The β-blocking activities of A and B were examined.
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谷 正宣, 青木 剛, 伊藤 貞雄, 松本 茂信, 秀嶋 麻美, 福島 かおる, 野澤 亮一, 前田 宜子, 田代 真由美, 横山 祐作, ...
1990 年 38 巻 12 号 p.
3261-3267
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
The Friedel-Crafts acylation of ethyl 1H-indole-2-carboxylate (1) with various acylating reagents having a functional group or hetero atom and the acylation of some derivatives (6, 7, 8, and 9) of ethyl 1H-indole-2-carboxylate (1) with simple acylating reagents are described. Acylation occurred at the C
3-position or on the benzene moiety (mainly at the C
5-position) of the indole nucleus. The regioselectivity of the above acylation of indoles (1, 6, 7, 8, and 9) is discussed.
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大石 悦男, 泰道 直方, 岩本 憲人, 宮下 晶, 東野 武郎
1990 年 38 巻 12 号 p.
3268-3272
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
The 1-substituted phthalazines 6 underwent inverse-electron-demand Diels-Alder reaction with the enamines 3 and ynamines 9, resulting in the formation of 1-substituted naphthalenes.Thus, 1-phthalazinecarbonitrile (6b) reacted with 3a-i to give the corresponding 1-naphthonitriles 7a-e, g, h and 2, 3-kihydro-1-naphthonitriles 8f, i, respectively. Similarly, reaction of 1-(methylsulfonyl)phthalazine (6c) with 3a, b, d, f gave the corresponding 1-(methylsulfonyl)naphthalenes 10a, b, d and 1-(methylsulfonyl)-2, 3-dihydronaphthalene 11f. Furthermore, 1-methylthio- (6e), 1-phenyl- (6f), 1-methyl-(6b), 1-chlorophthalazines (6h) and phthalazine (6a) reacted with 3a to afford the corresponding 4-substituted 2, 3-dihydro-1H-benz[f]indenes 12e-h, a, respectively.A similar ring transformation was found to proceed between 1, 4-phthalazinedicarbonitrile (14) and 1-methyl-1H-indole (13), giving the benzo[b]carbazoledicarbonitrile (15).Compounds 6b and 6c also underwent inverse-electron-demand Diels-Alder reaction with the ynamines 9a, b to give the corresponding 1-cyano-16a, b and 1-(methylsulfonyl)naphthalenes 17a, b, respectively.
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星野 修, 伊藤 勝彦, 梅澤 文輔, 秋田 弘幸, 大石 武
1990 年 38 巻 12 号 p.
3273-3276
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
Kinetic resolution of (±)-4-acyloxytetrahydroisoquinolines (5-7) by use of lipases immobilized on Celite in isooctane or cyclohexane saturated with water was carried out to give 4S-(+)-tetrahydroisoquinolin-4-ol (8) in a high optical purity. The absolute configuration of (+)-8 was determined by comparison of the spectral data and specific rotation with those of authentic 4R-(-)-tetrahydroisoquinolin-4-ol (8) derived from R-(-)-epinephrine (9).
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星野 修, 伊藤 勝彦, 棚橋 留香, 梅澤 文輔, 秋田 弘幸, 大石 武
1990 年 38 巻 12 号 p.
3277-3279
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
The stereostructure of (+)-roemecarine, a new 1-benzyl-1, 2, 3, 4-tetrahydroisoquinoline having a hydroxyl group at the 4-position, was confirmed to be 1, 4-trans by synthesis of (±)-epiroemecarine (1) and (±)-roemecarine (5) via o-quinol acetates of isocodamine (4). Furthermore, (+)- and (-)-roemecarine (5) were synthesized in good chemical and optical yields by kinetic resolution of (±)-4-O-acetyl- (3) or (±)-4, 6-O, O-diacetylroemecarine (7) by the use of immobilized lipase OF-360 (Candida cylindracea) in organic solvents. (+)-Roemecarine (5) was proved to have 1S, 4S-configuration.
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東 邦雄, 中山 清, 曽我 恒彦, 塩谷 恵美子, 魚戸 浩一, 日馬 恒雄
1990 年 38 巻 12 号 p.
3280-3282
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
A Novel stereoselective glycosidation was achieved by the combined use of trityl halide and Lewis acid under mild reaction conditions. The stereoselectivity was found to be drastically changed by the presence of trityl halide.
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佐野 武弘, 堀口 よし江, 津田 喜典
1990 年 38 巻 12 号 p.
3283-3295
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
The first synthesis of derivatives of azatropolone, a new nitrogen heterocycle, and some of their chemical properties are described. Two routes to the azatropolone skeletone were developed; one is the photocycloaddition of dioxopyrrolines 1 to acetylenes followed by thermolysis or photolysis of the resulting cyclobutenes 2 to give the azatropolones 7 or 8, and the other is the ring expansion reaction of the cyclobutanes 5 obtained by the photocycloaddition of 1 to olefins followed by 2, 3-dichloro-5, 6-dicyano-1, 4-benzoquinone dehydrogenation of the resulting dihydroazepines 16 to give the azatropolones 7.The azatropolone rapidly consumed diazomethane; thus 7 gave the 3-O-methylazatropolones 18, while 8 gave mixtures of 3-O-methyl-19 and 2-O-methylazatropolones 20. The position of methylation was proved by the unambiguous synthesis of 18 and of 2-O-ethyl derivatives 24 from 16. The azatropolones 7 and 8, when treated with a protonic solvent, readily underwent a ring contraction reaction giving rise to the pyridine-2-carboxylates 29 and 30, respectively, thus demonstrating that the azatropolone nucleus has a strongly electrophilic character.
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吉田 隆志, 難波 治, 陳 玲, 劉 延沢, 奥田 拓男
1990 年 38 巻 12 号 p.
3296-3302
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
Three new ellagitannins, prostratins A, B and C, along with eleven known polyphenols including three hydrolyzable tannin oligomers (rugosins D, E and G), have been isolated from the leaves of Euphorbia prostrata AIT. A hydrolyzable tannin trimer, prostatin B, and two dimers, rugosins D and E, were also obtained from the leaves of Loropetalum Chinense OLIV.
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岡崎 健男, 車谷 勝行, 寒河江 葉子, 梶原 正宏
1990 年 38 巻 12 号 p.
3303-3307
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
The biosynthetic pathway of chlorophylla-a formation in the photosynthetic phytoflagellate Englena gracilis was investigated by administration of
2H- and
13C-labeled precursors. L-[1-
13C]Glutamate was incorporated into eight carbon atoms in the chlorophyll macrocycle via δ-aminolevulinic acid formed through the C-5 pathway. A low incorporation of D-[1-
13C]glutamate was also observed. [2-
13C]Glycine was preferentially incorporated into the methyl ester carbon of chlorophyll via the one-carbon metabolic pathway, but not via the Shemin pathway. Feeding experiments with
2H-, and
2H,
13C-labeled glycine yielded labeled chlorophylls, which were subjected to nuclear magnetic resonance and mass spectra analyses to obtain detailed information about the biosynthetic orgin of the hydrogen atoms.
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波多野 力, 小川 登, 安原 多恵子, 奥田 拓男
1990 年 38 巻 12 号 p.
3308-3313
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
Three new hydrolyzable tannins, rugosins A (1), B (2) and C (3), were isolated from flower petals of Rosa rugosa THUNB. (Rosaceae), and their structures, including the orientation of the valoneoyl group, were established based on chemical evidence and spectroscopic analysis, utilizing two-dimensional nuclear magnetic resonance spectral data.
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片山 定, 渡辺 利郎, 山内 昌茂
1990 年 38 巻 12 号 p.
3314-3316
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
A new preparation method for a variety of stable sulfur ylides is described. Reactions of the Corey-Kim reagent with active methylene compounds having two electron withdrawing groups in the presence of triethylamine afforded stable surfur ylides in satisfactory yields.
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千葉 卓男, 高田 芳宏, 金子 主税, 木内 文之, 津田 喜典
1990 年 38 巻 12 号 p.
3317-3325
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
The cycloaddition of isoquinolone and its N-methyl derivative to all the chlorinated ethylenes has been studied. The structures of all of the photoadducts were determined on the basis of X-ray crystallographic analysis as well as nuclear magnetic resonance spectroscopy and it was found that the cyclobutane rings in the adducts took puckered conformation. The details of the two-step closure process via biradical intermediates are discussed and it is concluded that σ-bond rotation prior to spin relaxation in the biradical intermediates takes a primary role in determination of the stereochemical outcome. The interesting fact that more trans products are formed from cis-dichloroethylene and more cis products from trans-dichloroethylene can also be explained in terms of the present proposal.
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藤井 澄三, 斎藤 徹, 久田 裕美, 新保 孝治
1990 年 38 巻 12 号 p.
3326-3330
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
The Dimroth rearrangement of 1-ethyladenine (6) to give N
6-ethyladenine (11)(91% yield) was accompanied with unusual hydrolytic deaminations to produce hypoxanthine (8)(2%) and 1-ethylhypoxanthine (14)(2%), when carried out in 0.2N aqueous NaOH at 100°C for 7h. Probable pathways leading to these by-products are discussed on the basis of the results of alkaline hydrolysis of 5-amino-N'-ethylimidazole-4-carboxamidine dihydrochloride (5), which yielded both 5-aminoimidazoli-4-carboxamide (9) and 5-amino-N-ethylimidazole-4-carboxamide (12). For structural identification, 14 was alternatively synthesized from inosine (17) through 1-ethylinosine (16), and 12 was synthesized from 16 through 5-amino-N-ethyl-1-β-D-ribofuranosylimidazole-4-carboxamide (15). Comparison of the reaction rates in the Dimroth rearrangements of 6·HClO
4 and 1-ethyl-9-methyladenine perchlorate [1·HClO
4 (R
1=Et; R
2=Me)] in H
2O at pH 6.92 and 8.70 (ionic strength 1.0) at 70°C has revealed that nonsubstitution at the 9-position decreases the rearrangement rate by a factor of 4-30 under these conditions.
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佐藤 達典, 伊藤 多美子, 石橋 弘行, 池田 正澄
1990 年 38 巻 12 号 p.
3331-3334
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
Treatment of N-[o-(alk-1-enyl)phenyl]-2-(methylsulfinyl)acetamides with trifluoroacetic anhydride gave 2(1H)-quinolinones or 2H-1-benzazepin-2-ones, depending upon the position of the substituents on the alkene double bond.
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花岡 美代次, 趙 元済, 吉田 修治, 笛木 司, 向 智里
1990 年 38 巻 12 号 p.
3335-3340
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
A novel method for the introduction of an oxy functionality at the C
12-position of the benzo[c]phenanthridine skeleton was developed. The method was successfully applied to a biomimetic synthesis of macarpine (3) from oxychelirubine (15), which was easily derived from the corresponding protoberberine (9).
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波多野 力, 小川 登, 新宮 徹朗, 奥田 拓男
1990 年 38 巻 12 号 p.
3341-3346
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
Three dimeric hydrolyzable tannins having a valoneoyl group, rugosins D (1), E (2) and F (3), and a trimeric hydrolyzable tannin having two valoneoyl groups, rugosin G (4), were isolated from flower petals of Rosa rugosa (Rosaceae), and their structures including the orientation of the valoneoyl groups were established.
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清水 千賀子, 大田 直樹, 阿知波 一雄
1990 年 38 巻 12 号 p.
3347-3354
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
New 1-acyl-sialosyl-glycerol derivatives (1a-dα, 1a-dβ, 2α, 2β, which mimic the structure of the capusular polysaccharide of group C meningococcal were synthesized by the use of a chiral glycerol derivative, and were found to have phospholipases A
2 and C inhibitory activities. Furthermore, syntheses of 2-palmitoyl-sialosyl-glycerol derivative (4α, 4β, 5α, 5β), galactosyl-glycerol derivative (6), and sialosyl-galactosyl-glycerol derivative (7) were carried out to examine the difference between these activities. Among these sialosyl derivatives, 3-palmitoyl-sialosyl-glycerol derivatives (1-3α, 1-3β) demonstrated the most potent inhibitory activities.
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柳沢 隆, 小坂井 一宏, 冨山 剛, 安並 正文, 高瀬 嘉平
1990 年 38 巻 12 号 p.
3355-3358
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
A series of alkylazulene-1-sodium sulfonate derivatives which has an isopropyl group at 6-position were synthesized, and their anti-ulcer activities were examined in Shay pylorus-ligated rats. The values of lipophilicity (log P) as a parameter of these new azulene derivatives were also examined in reference to the structure-activity relationship. The optimum value of log P, which showed maximal anti-ulcer activity, was about -0.46. Among the derivatives of azulene examined, 3-ethyl-6-isopropylazulene-1-sodium sulfonate (compound IXb : KT1-785) exhibited the most potent inhibitory action against Shay ulcer, and its anti-peptic activity was similar to that of 3-ethyl-7-isopropylazulene-1-sodium sulfonate (KT1-32). It also had more activity than guaiazulene sodium sulfonate (GAS). Furthermore, KT1-785 was extremely stable under heating as compared to GAS.
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宮本 皓之, 松本 純一
1990 年 38 巻 12 号 p.
3359-3365
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
Chemical modification of pyridonecarboxylic acid antibacterials with a 1, 8-naphthuridine ring, such as enoxacin and tosufloxacin, to their 2-aza derivatives was studied. A new series of 1, 7-disubstituted 6-fluoro-4(1H)-oxopyrido[2, 3-c]pyridazine-3-carboxylic acids (25-27) was prepared by a route involving either alkylation of ethyl 6-fluoro-4(1H)-oxo-7-(p-tolylthio)pyrido[2, 3-c]pyridazine-3-carboxylate (7) or intramolecular cyclization of ethyl 2-(2, 6-dichloro-5-fluoronicotinoyl)-2-[2-(p-fluorophenyl)hydrazono]acetate (20), followed by displacement reaction with cyclic amines at C-7; the N-1 substituent in these compounds included of ethyl, 2-fluoroethyl and p-fluorophenyl groups, and the C-7 functional group comprised variously-substituted piperazines and pyrrolidines. Antibacterial activities of these compounds were markedly inferior to those of enoxacin and tosufloxacin.
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日馬 恒雄, 曽我 恒彦, 塩谷 恵美子, 中山 清, 中島 弘人, 長田 恭明, 小野 承行, 楠本 正一, 芝 哲夫
1990 年 38 巻 12 号 p.
3366-3372
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
Three novel lipid A analogs, which have an α- or β-glycosidically bound phosphonooxyethyl group instead of the α-glycosyl phosphate group of natural lipid A, were synthesized. The first analog (2) had an α-phosphonooxyethyl group on the identical acylated disaccharide 4'-phosphate structure found in natural lipid A (from Escherichia coli) and hence differed from the latter only in the nature of the acidec group at position 1. The second one (3) had tetradecanolyl groups in place of the two (R)-3-hydroxytetradecanoyl groups bound to the 2- and 3-hydroxyl function of 2, retaining the α-phosphonooxyehyl group. The structure of the third analog (4) was the same as that of 3 except that the phosphonooxyethyl group of the former was β-oriented.Compounds 2 and 3 exhibited potent activity against Meth A at the same level as natural lipid A, whereas 4 showed less activity. This fact revealed that the glycosidic phosphate is not a prerequisite for the antitumor activity of lipopolysaccharide. It can be replaced with a phosphonooxyethyl group without any loss of activity provided that the α-anomeric configuration at C-1 is retained. The replacement of the hydroxytetradecanoyl groups with tetradecanoyl groups does not change the activity either.
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森口 郁生, 広野 修一, 劉 謙, 松下 泰雄, 中川 祟子
1990 年 38 巻 12 号 p.
3373-3379
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
Fuzzy adaptive least squares (FALS), a pattern recognition method designed to correlate molecular structure with activity rating, has been developed. A novel feature of FALS is that the degree to which each sample belongs to an activity class is given using a membership function. The algorithm involves an iterative modification of forcing factors to maximize the sum of the membership function values over all samples. This paper first describes the method and calculation procedure of FALS89 (1989 version of FALS), and then shows its application to the correlation of structure with a potency rating of anticarcinogenic mitomycin derivatives and arginine-vasopressin antagonists. FALS89 applied to these samples showed considerably high reliability in both recognition and leave-one-out prediction.
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神田 博史, 田中 誠司, 山岡 康利
1990 年 38 巻 12 号 p.
3380-3383
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
From the leaves of Acanthopanax hypoleucus MAKINO (Araliaceae), five triterpenoidal saponins, having oleanolic acid and hederagenin as sapogenins, were isolated.On the basis of chemical and spectral data, the structures of two new saponins, named hypoleucosides A (1), and B (5) were elucidated as follows : 1; 3-O-β-D-glucopyranosyl 11α-methoxy-oleanolic acid 28-O-β-D-glucopyranosyl ester, 5; 3-O-β-D-glucopyranosyl-(1→2)-α-L-arabinopyranosyl-(1→4)-β-D-glucopyranosyl oleanolic acid 28-O-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl ester.
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糸川 秀治, 戸塚 伸夫, 森田 博史, 竹谷 孝一, 飯高 洋一, / 持留 万里夫, Mario MOTIDOME
1990 年 38 巻 12 号 p.
3384-3388
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
New antitumor clerodane diterpenes, named casearins A-F, have been isolated from the leaves of Casearia sylvestris Sw. (Flacourtiaceae). These structures have been completely elucidated by two dimensional nuclear magnetic resonance, circular dichroism spectroscopy, X-ray analysis, and chemical evidences.
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米田 道明, 辻本 和雄, 大橋 守, 白土 正三, 大川 泰, 伊佐 公男
1990 年 38 巻 12 号 p.
3389-3394
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
Fast atom bombardment (FAB) or liquid secondary ion mass spectra (LSIMS) of nipradilol and its analogues exhibit intense [MH-45]
+ ions corresponding to MH
+ ions of those hydrolysis products. Although FAB low energy collision-activated dissociation (CAD)-tandem mass spectrometry (MS/MS) using a triple-stage quadrupole-type instrument indicates that both ions are identical, the FAB(LSIMS) B/E constant linked scanning spectra of the ions are different from each other. To elucidate the reason for the two methods used for the same purpose giving different results, FAB high energy CAD-MS/MS was carried out using an EBE sector-type instrument. Comparison between the results of the B/E constant linked scanning and those of the high energy CAD-MS/MS indicated that the discrepancy is due to the poor resolution of precursor ions in the linked scanning at the B/E constant. It was also found that the high energy CAD-MS/MS spectra differed from the low energy CAD-MS/MS spectra owing to the difference in CAD energy between the two instruments. Decomposition products of nipradilol under FAB conditions were identified by high performance liquid chromatography and confirmed that the structures of the [MH-45]
+ ions were MH
+ of the hydrolysis products. The reaction products by fast atom bombardment under FAB conditions turned out to be the corresponding hydrolysis products which are different from those obtained by heating in glycerol.
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佐藤 均, 竹田 和喜, 寺崎 哲也, 辻 彰
1990 年 38 巻 12 号 p.
3395-3399
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
Binding of human β-endorphin (β-EP) to rat renal basolateral membranes was characterized using [
125I]Try
27-β-EP ([
125I]β-EP) as a primary ligand. Ten millimolar of ethylenediaminetetra acetic acid (EDTA) completely inhibited the degradation of [
125I]β-EP in the incubation mixture at 4°C, thus making it possible to quantitatively examine the [
125I]β-EP binding. The specific binding of [
125I]β-EP to the basolateral membranes was reversible and saturable, and a nonlinear least-squares regression analysis of a saturation isotherm revealed two different classes of specific binding sites. One class had an apparent dissociation constant (Kd) of 0.68nM and a lower number of binding sites (33fmol/mg protein), whereas the other class had a lower affinity (apparent Kd of 210nM) and a higher number of binding sites (7.3pmol/mg protein). Inhibition of the [
125I]β-EP binding by naloxone (10μM) was approximately only 20%, and that by D-Ala
2-D-Leu
5-enkephalin (10μM) was null, suggesting the major role of a non-opioid binding component in specific [
125I]β-EP binding to basolateral membranes. Moreover, a 50% inhibition by 10μM of dynorphin(1-13) suggests that a certain region of the primary structure of β-EP, excluding at least the NH
2-terminal enkephalin sequence, is of particular importance for the [
125I]β-EP binding. These lines of evidence suggest the existence of two different classes of specific binding sites for β-EP on the renal basolateral membranes, and the high- and low-affinity bindings may be attributed to opioid and non-opioid receptors, respectively, as judged by known characteristics of opioid and non-opioid receptors in other peripheral tissues.
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古茶 友二, 福田 照夫, 奥山 典生
1990 年 38 巻 12 号 p.
3400-3406
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
Lactate dehydrogenase (LDH) was purified from rat and bovine tissues by affinity chromatography on immobilized colchicine and used for the separation of isoenzymes by high-performance anion-exchange liquid chromatography (HPLC). This analysis showed the splitting of rat H
2M
2 into three peaks and of bovine H
2M
2 into two peaks. The heat stability, inactivation rate of urea and electrophoretic mobility of isoenzymes were examined and these analyses indicated differences in physicochemical properities for the respective peaks of rat and bovine H
2M
2. In hybridization experiments, the splitting of H
2M
2 into three peaks was achieved only with the combination of rat H
4 and rat M
4, while the other combinations of bovine H
4 and bovine M
4, of rat H
4 and M
4 and of bovine H
4 and rat M
4 resulted in two H
2M
2 peaks.These results demonstrate that H
2M
2 of LDH in normal rat and bovine tissues is always split into two or three peaks by HPLC and that these H
2M
2 peaks have different physicochemical propertites, suggesting the existence of three possible geometrical isomers of H
2M
2.
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松田 兆史, 藤本 幸男, 宮下 厚, 秋浜 澄行
1990 年 38 巻 12 号 p.
3407-3409
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
Two forms of basic arginine ester hydrolyzing enzymes were found in human male urine, and their partial purification was performed using lima bean trypsin inhibitor (LBTI) affinity adsorption and Cellulofine GCL-2000 gel chromatography. The forms tentatively called basic human urinary arginine esterase-1 (BHUAE-1) and -2 (BHUAE-2), had respective estimated molecular weights of about 4.5×10
4 and 1.8×10
4 daltons, with pH optima observed at 9.5 and 10.0. These two new enzymes in the human male urine were different from human renal urokinases.
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永倉 直樹, 小林 忠正, 清水 忠順, 増沢 俊幸, 柳原 保武
1990 年 38 巻 12 号 p.
3410-3413
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
immunological properties of delayed-type hypersensitivity (DTH) reaction induced by cephalexin (CEX) in ginea pigs were investigated. The animals were immunized with CEX using Freund's complete adjuvant. The time course of CEX-induced erythema showed some differences compared with that of classical DTH reaction. The erythema appeared at 6h after intradermal administration of CEX, reached maximum size at 12 to 24h and to be visible until 72h. By enzyme-liked immunosorbent assay, anti-CEX antibody was detected in only one of 15 animals tested. Normal animals (recipients) which had received immune sera from CEX-sensitized animals (donors) showed no skin reaction to CEX. In contrast, reaction to CEX was observed in recipient animals which had received a local transfer of lymphocytes or T cells from CEX sensitized animals. In immunopharmacological study, cyclosporin A suppressed the skin reaction but cyclophosphamide did not. Administration of carrageenan, an inhibitor of macrophage function, had no effect on expression of the reaction. Post administration (1 or 15h) of clemastine, an anti-histamine drug, did not affect the reaction. By histological examination, the infiltrating cell-types at the reaction site were mainly composed of mononuclear cells and neutrophils, but no basophils, indicating that CEX-induced DTH reaction is tuberculin-type DTH and not a cutaneous basophil hypersensitivity reaction.
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小島 尚, 菊川 清見, 小杉 弘子
1990 年 38 巻 12 号 p.
3414-3418
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
The fluorometric thiobarbituric acid (TBA) assay of blood plasma was performed under various conditions in order to assess whether the assay reflects lipid peroxidation. The TBA-reactivity of malonaldehyde was not dependent on the pH values of the reaction and was little affected by tert-butyl hydroperoxide (tert-BuOOH). The rectivity of 2, 4-nonadienal and 2-hexenal, which was maximal at pH 3-4 and at above pH 4, respectively, was dramatically enhanced by tert-BuOOH and ferric ion, and suppressed by ethylenediaminetetraacetic acid (EDTA). The pigment formation from oxidized low-density-lipoprotein was maximal at about pH 5, markedly enhanced by ferric ion and suppressed by EDTA, indicating that the TBA-reactive substances in the oxidized lipoprotein were composed of malonaldehyde, alkadienals and alkenals originated from lipid peroxidation. The pigment formation from plasma and its phosphotungstic acid precipitate was maximal at pH 4 and at below pH 2, respectively. The effect of tert-BuOOH, ferric ion and EDTA was not significant. The major TBA-reactive substances from plasma may be compounds other than malonaldehyde, alkadienals, alkenals and those in the oxidized lipoprotein. The TBA-reactivity of plasma does not appear to be specific to lipid peroxidation.
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榊原 由美子, 小田 泰子, 平田 愛子, 松橋 通生, 佐藤 良博
1990 年 38 巻 12 号 p.
3419-3422
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
We have reported that meso-hexestrol, a synthetic estrogen, inhibits microtubule assevbly and induces microtubule proteins into twisted ribbon structures. On the other hand, Serrano et al. Proved that S-tubulin, which lacks the C-terminal moiety of tubulin subunits, assembles into sheet structures in the absence of microtubule-associated proteins (MAPs). In the present investigation, we attempted to clarify whether meso-hexestrol could induce the ribbon structure from S-tubuin. meso-Hexestrol delayed the initiation of polymerization of S-tubulin into sheet structures in a dose-dependent manner below 50μM. But the effect of meso-hexestrol on S-tubulin was reduced in the presence of either tau or microtubule-associated protein 2 (MAP2) in a MAPs-concentration-dependent manner. At concentrations higher than 100μM, meso-hexestrol inhibited the polymerization of S-tubulin into sheet structures, without forming ribbon structures. The present results may indicate that moso-hexestrol interacts with S-tubulin, and its interaction is affected by MAPs.
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/ 仲井 由宣, / 山本 恵司, / , Keiji YAMAMOTO, Aly Abdel Zather Abdel RAHMAN, S ...
1990 年 38 巻 12 号 p.
3423-3427
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
Complex formation of nitrazepam with heptakis-(2, 6-di-O-methyl)-β-cyclodextrin (DM)-β-CyD) and heptakis-(2, 3, 6-tri-O-methyl)-β-cyclodextrin (TM-β-CyD) together with α-, β-, and γ-cyclodextrins (CyDs) in aqueous solution was confirmed by the solubility method. A
L type phase solubility diagrams were obtained in all cases. The highest stability constant and the highest solubilized amount of nitrazepam was obtained with DM-β-CyD, in the order DM-β-CyD>β-CyD>TM-β-CyD>γ-CyD>α-CyD. Coplex formation of nitrazepam with DM-β-CyD and TM-β-CyD in the solid state was assessed by differential scanning calorimetry (DSC), infrared (IR) spectroscopy and X-ray diffractometry. Crystalline inclusion complex of nitrazepam with DM-β-CyD in 1 : 2 molar ratio was botained by the coprecipitation method. X-Ray diffraction analyses explained that nitrazepam was transformed from the crystalline to non-crystalline (amorphous) state by grinding with methylated β-CyDs. DSC analyses revealed that the heat of fusion due to nitrazepam disappeared in the ground ixture and coprecipitate of nitrazepam with DM-β-CyD in 1 : 2 molar ratio, which demonstrated the optimum content of dispersal nitrazepam with DM-β-CyD in the solid state. IR spectra showed that there were higher frequency shifts for the carbonyl stretching band of nitrazepam in the ground mixtures and coprecipitates of DM-β-CyD and TM-β-CyD similar to the case of nitrazepam in CHCl
3 solution, which were considered due to the monomolecular dispersion of nitrazepam in a hydrophobic environment.
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渡辺 淳, 樋口 潤哉, 林 弥生, 湯浅 博昭, 尾関 昭二
1990 年 38 巻 12 号 p.
3428-3433
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
Effects of oral administration of NaCl on salivary and systemic clearance of Li
+ were investigated following bolus intravenous administration of LiCl in male beagle dogs. Fifty ml of NaCl solution (100meq/l) was administered orally 7 times at 1h intervals. Gustatory stimulation was continued for 390min using citric acid solution. Saliva was collected by means of permanent fistulae for parotid and mandibular-sublingual glands. Salivary clearance of Li
+ was markedly increased by continuous stimulation of salivation, and was enhanced further after oral administration of NaCl solution. Renal clearance of Li
+ showed a decreasing tendency under continuous salivation compared with the condition without gustatory stimulation; however, this decreasing tendency disappeared after oral administration of NaCl solution. Consequently, systemic clearance of Li
+ was increased due to the contribution of increased salivary clearance. Enhancement of Salivary Li
+ clearance after administration of NaCl suggests the salivary excretion mechanism of Li
+ may include a reabseoption process, like its renal excretion. Administration of NaCl solution had similar effects on salivary and systemic clearances of K
+ to those on Li
+ clearances, and a significant correlation was observed between Li
+ and K
+ clearances of both salizary gland and kidney.
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早川 栄治, 古家 邦敏, 黒田 徳幸, 森山 圭雄, 近藤 明
1990 年 38 巻 12 号 p.
3434-3439
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
Doxorubicin hydrochloride interacts with various metal salts in aqueous solution and is associated with the prolongation of dissolution time. When a doxorubicin hydrochloride freeze-dried product was dissolved with isotonic sodium chloride solution, several small jelly-like spheres appeared locally. The futher addition of NaCl promoted the gel formation and the whole solution turned into a viscous liquid.A diffusion experiment using filter paper and X-ray microanalyzer analysis indicated that the highly viscous structure, which was the cause of the prolongation of dissolution time, was formed on the surface of the small spheres by the interaction of doxorubicin with NaCl.We found that methyl parahydroxybenzoate L-phenyl alaninem, urea, and citric acid, etc. had a shortening effect on the dissolution time of the doxorubicin hydrochloride freeze-dried product, and moreover, these additives reduced the viscosity of the aqueous solution of doxorubicin hydrochloride enhanced by the addition of NaCl.
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石野 隆三, 吉野 廣祐, 平川 善行, 野田 和夫
1990 年 38 巻 12 号 p.
3440-3445
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
To examine the influence of the internal structure of a wax matrix tablet on in vitro drug release, the release rates of several tablets consisting of various proportions of drug and wax were compared with the water penetration rates from the compressed and lateral surfaces of the tablets. The penetration rates from the lateral surface were found to be much faster than those from the compressed surface in all cases. A theoretical equation involving a two-dissolving-direction was derived on the basis of the boundary retreating concept. The retreating rate constants deduced from the dissolution results were well coincident with the values directly determined by the needle penetration method, suggesting good applicability of the proposed equation. The results suggest that the tortuosity of the water channels created in a tablet during dissolution is generally smaller in the horizontal direction than that in the vertical direction. This would be caused by the drug particles or granules being elongated in the horizontal direction by compression.
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星 勝治, 藤野 澄子
1990 年 38 巻 12 号 p.
3446-3448
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
The effect of phenobarbital (PB) or amitriptyline (AMT) on phospholipid metabolism was studied in rat liver. Administration of PB or AMT caused a marked increase in the microsomal phosphatidylcholine (PC) content. In this context, the activities of glycerophosphate acyltransferase (GAT), phosphatidate cytidylyltransferase (PCT), phosphatidate phosphohydrolase (PPH) and choline phosphotransferase (CPT) in the liver were all increased by PB. In contrast, the activities of GAT and PCT were little affected by AMT, while those of PPH and CPT were significantly increased by AMT. These findings suggest that AMT or PB would increase hepatic microsomal PC synthesis through inducing PPH and then CPT.
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森 啓, 石山 〓夫, 秋田 弘幸, 鈴木 邦夫, 光岡 知足, 大石 武
1990 年 38 巻 12 号 p.
3449-3451
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
Microbial reduction of 1-phenyl-2-nitro-1-propen (3) was carried out using 57 stains of yeast, 40 strains of aerobic and facultatively anaerobic bacteria and 40 strains of strictly anaerobic bacteria. Nine strains of yeast (Candida tropicalis, etc., ) had the ability to reduce (3) to 1-phenyl-2-nitropropane (1)(94.1%-60.3% yield). The ability of the aerobic and anaerobic bacteria was weaker than yeast (35.6%-14.0% and less than 5%, respectively). When 11 straines of strictly anaerobic bacteria (Clostridium innocuum etc., ) were used, a final reduced product like amphetamine (2) was detected, although the efficiency of reduction was very poor.
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畑中 朋美, 井沼 正美, 杉林 堅次, 森本 雍憲
1990 年 38 巻 12 号 p.
3452-3459
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
In order to measure the contribution of lipid and pore (aqueous) pathways to the total skin permeation of drugs, and to establish a predictive method for the steady state permeation rate of drugs, the relationship between permeability through excised hairless rat skin and some physicochemical properties of several drugs were compared with those through polydimethylsiloxane (silicone) and poly(2-hydroxyethyl methacrylate)(pHEMA) membranes, as typical solution-diffusion and porous membranes, respectively. A linear relationship was found between the permeability coefficients of drugs for the silicone membrane and their octanol/water partition coefficients. For the pHEMA membrane, the permeability coefficients were almost constant independent of the partition coefficient. On the other hand, the skin permeation properties could be classified into two types : one involves the case of lipophilic drugs, where the permeability coefficient is correlated to the partition coefficient, similar to the silicone, membrane; and the other involves hydrophilic drugs, where the permeability coefficients were almost constant, similar to pHEMA membrane. From the above results, the stratum corneum, the main barrier in skin, could be described as a membrane having two parallel permeation pathways : lipid and pore pathways. An equation for predicting the steady state permeation rate of drugs was derived based on this skin permeation model.
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厚海 修吾, 中野 真人, 小池 隆, 田中 誠一, 船橋 洋, 橋本 純子, 森島 甫
1990 年 38 巻 12 号 p.
3460-3462
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
A dihydroxyethylene isostere, (2S, 3R, 4S)-4-amino-5-cyclohexyl-1-morpholino-2, 3-pentanediol, which is a component of non-peptidic, orally active, low-molecular-weight renin inhibitors, was synthesized stereospecifically starting from prochiral divinylcarbinol via the Sharpless epoxidation.
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藤井 澄三, 板谷 泰助, 田中 孚美子, 斎藤 徹, 久田 裕美
1990 年 38 巻 12 号 p.
3463-3465
発行日: 1990/12/25
公開日: 2008/03/31
ジャーナル
フリー
A detailed account is given of the synthesis and glycosidec cleavage of 1-ehyladenosine (2b), which established an alternative synthesis of 1-ethyladenine (3b). Ethylation of adenosine (1) with EtI in AcNMe
2 at 35-38°C for 90h gave 2b·HI in 54% yield. The hydriodide 2b·HI was readily converted into the perchlorate 2b·HClO
4 and into the free nucleoside 2b. Treatment of 2b·HI with 0.5N aqueous HCl at 92-94°C for 30min or that of 2b·HClO
4 with boiling AcOH for 60min produced the aglycone 3b in good yield. The free base easily formed the hydrochloride 3b·HCl, and the perchlorate 3b·HClO
4 as well.
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