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風間 舜介, 神谷 護, 赤堀 幸男
1991 年 39 巻 12 号 p.
3103-3105
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
A novel mechanism of the photochemical reaction of 10-(9H-xanthenylidene)-9(10H)-anthracenone (XA) was proposed on the basis of absorption spectrum canges observed upon photoirradiation, and the temperature effects upon the quantum yields of the radical formation and cyclization reaction. The cyclization reaction of XA has a negative apparent activation energy value (-8.5 kcal/mol), while the radical formation from XA has a positive activation energy value (7.9 kcal/mol). The negative value of the aparent activation energy of the cyclization reaction was explained as a rasult of the competing effect of radical scavenging by oxygen associated with the conformation change which occurs with larger activation energy but smaler steric restriction compared to the cyclization reaction
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広野 修一, 劉 謙, 森口 郁生
1991 年 39 巻 12 号 p.
3106-3109
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
For 41 hydrocarbons including paraffins, olefins, acetylenes and aromatics, the solvent accessible surface areas partitioned according to the electrostatic molecular potential levels have been computed and correlated with the hydrophobic free energies derived from their aqueous solubilities. The results indicate that the free energy is a linear function of the areas of two parts of the solvent accessible surface, one of which has an electrostatic potential above -1 kcal/mol and the other has a potential of -1 kcal/mol or below. The coefficients of the two parameters are about 25 cal/mol/Å
2 at 25°C, respectively, and the multiple correlation coefficeint is 0.987.
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葛谷 昌之, 野口 章公, 牧 敬文, 酒向 孫市
1991 年 39 巻 12 号 p.
3110-3113
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
The specific photochemical reactivity of 2, 4, 6, 8(1H, 3H, 7H, 9H)-pyrimido[5, 4-g]pteridinetetrone 5-oxide (1), an effective photochemical oxygen-atom transfer agent, was discussed based on the results of molecular orbital (INDO/S-CI (intermediate neglect of differential overlap/spectrum-conflguration interaction)) calculations of the excited states, in comparison with several simple aromatic N-oxides, pyridine 1-oxide (2), pyrazine 1-oxide (3), acridine 10-oxide (4), and phenazine 5-oxide (5). The lowerst π-π
* excited singlet (S
x-x*1) state of 1 was most characterized by the high proportion of the ψ
a2→ψ
*<b
2> transition for the CI (conflguration interaction) state and by the marked decrease of the N-O bond order, distinct from those of 2-5. The low reactivity in photorearrangement of 1 was interpreted to result from the decrease of the N-O bond order in the S
x-x*1 state. Also, the high photochemical oxygen-atom transfer reactivity of 1 was well correlated to the special features of the lowest unoccupied molecular orbital in the ground state.
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横山 祥子, 上田 文雄, 藤江 忠雄
1991 年 39 巻 12 号 p.
3114-3119
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
The rates of release of nicotinamide (NAA) from fatty acid (FA)-NAA complexes, FA-NAA, were determined at various temperatures, and the thermodynamic quantities for the release of NAA were estimated. The results were compared with the previous results obtained for FA-thiamine disulfide (TDS) complexes, (FA)
6(TDS). The values of activation enthalpy (ΔH
〓) and activation entropy (ΔS
〓) for the releaes of NAA from FA-NAA were positive and negative, respectively, indicating that the release of NAA is disadvantageous from not only enthalpic but aso entropic viewpoints. The plots of ΔH
〓 against the carbon number (n) in the constituent FA showed a zig-zag line wiht an upward convex at an odd-numbered position and teh polts of the absolute values of ∣-Δ
〓∣ showed a zig-zag line wiht a downward convex at an odd-numbered position, through the positive values ΔH
〓 increases and the negative value of ΔS
〓 decreases with an increasing n for either even-numbered or odd-numbered FA. It was found that the release of NAA from FA-NAA formed with odd-numbered FA is more disadvantageous enthelpically but more advantageous entropically as compared with that from FA-NAA formed with even-numbered FA. THis phenomenon was simillar to that observed for (FA)
6(TDS). Furthermore, it is suggested that FA-NAA is formed at least by van der Waals forces and hydrophobic interactions and that van der Waals forces are dominant for the formation of FA-NAA formed with odd-numbered FA and that hydrophobic interactions are dominant for the formation of FA-NAA formed with even-numberes FA.
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竹内 義雄, 高木 久美子, 永田 和弘, 小泉 徹
1991 年 39 巻 12 号 p.
3120-3122
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
The first synthesis of α-fluoro-α-nitrocarboxamides 11b, c has been achieved by ammonolysis of the corresponding ethyl esters 6b, c. However, α-fluoro-α-nitrocarboxylic acids 8a-c derived from the corresponding esters 6a-c were found to decarboxylate readily to form 1-fluoro-1-nitroalkanes 9a-c. Reduction of the α-fluoro-α-nitrocarboxamide derivatives 11b, c produced the defluorination products 12b, c instead of the desired novel α-fluoro-α-aminocarboxamide 2.
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渡辺 三明, 川西 建司, 秋吉 隆治, 古川 淳
1991 年 39 巻 12 号 p.
3123-3131
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
A general synthetic method was developed for 2-aryl-2, 3-dihydrobenzo[b]furans via regioselective lithiation of ortho-tolyl tetramethylphosphorodiamidates followed by addition of aromatic aldehydes as a key step. ortho-Tolyl tetramethylphosphorodiamidates were regioselectively lithiated with sec-BuLi in tetrahydrofuran at -105°C to give benzylic lithio species. The resulting lithio species were reacted with aromatic aldehydes to provide 1, 2-diarylethanolderivatives. Reductive removal of the phosphoryl group with lithium aluminum hydride followed by acidic treatment led to 2-aryl-2, 3-dihydrobenzo[b]furans in good overall yields. The utility of this strategy was demonstrated in regioselective syntheses of highly substituted neolignan natural products, such as (±)-licarin B and (±)-carnatol, starting from O-bis(dimethylamino)phosphorylated eugenol or isoeugenol.
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林 雲蓮, 凍 玉麟, 郭 悦雄
1991 年 39 巻 12 号 p.
3132-3135
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
The following constituents were isolated from the roots of Derris Laxiflora BENTH : flemichapparin-B (1), 3'-methoxylupinifolin (2a), lupinifolin (2b), β-amyrin (3), lupeol (4), prunetin (5), laxifolin (6a), and isolaxifolin (7a). Compounds 2a, 6a, and 7a are new flavonoids, and their structures were determined on the basis of spectran and chemical evidence.
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高橋 浩, 津吹 猛, 東山 公男
1991 年 39 巻 12 号 p.
3136-3139
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
Highly diastereoselective reaction of chiral o-[2-(1, 3-Oxazolidinyl)]benzaldehydes (4-6) with alkylmetallic reagents provides a new synthetic method for chiral 3-alkylphthalides.
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中村 光延, 古畑 公夫, 山崎 聡子, 小倉 治夫
1991 年 39 巻 12 号 p.
3140-3144
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
Several α- and β-N-glycosides of 3-deoxy-D-glycero-D-galacto-2-nonulosonic acid (1, KDN) were synthesized under Vorbruggen and Williamson reaction conditions. Two hexa-O-acetyl derivatives of 1 were treated with trimethylsilyl deriatives of pyrimidine, 5-fluoropyrimidine and 5-methylpyrimidine, and azidotrimethylsilane so give mixtures of α- and -β-N-glycoside derivatives of 1. Two penta-O-acetyl-2-chloro derivatives of 1 were treated with the sodium salts of 2, 4(1H, 3H)-pyrimidinedione, 5-fluoro-2, 4(1H, 3H)-pyrimidinedione and 5-methyl-2, 4(1H, 3H)-pyimidinedione to give only the α-N-glycosides. THe anomeric configurations of these compounds could be elucidated on the basis of the coupling pattern of C-1 in
13C-nuclear magnetic resonance spectral analysis.
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渡辺 敦子, 高橋 弘幸, 鎌倉 浩之, 坂口 晋, 大崎 正子, 外山 悟, 水間 由花, 上田 育子, 村上 泰興
1991 年 39 巻 12 号 p.
3145-3152
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
Syntheses of benz[f]indoles from 1, 2-disubstituted naphthalene derivatives by means of cyclization reactions were attempted. The Fischer indolization of 1-methyl-(5a), 1-chloro-(5b), or 1-nitro-(5c)-2-naphthylhydrazones gave only benz[e]indole derivative or decomposed products, and the desired 9-substituted benz[f]indole (3) was not produced. On the other hand, the Fischer indolization of 2-methoxy-1-naphthylhydrazone (17) gave ethyl 5-chlorobenz[g]indole-2-carboxylate (19). The hemetsberger reaction of 1-methyoxy-2-naphthylazido acrylate (26a) gave an azirine (28a) and a nitrile (29a), whereas the same reaction of 1-chloro-2-naphthylazido acrylate (26b) gave the desired 4-chlorobenz[f]indole in a poor yield together with large amounts of by-products, the azirine (28b), the nitrile (29b) and the benz[g]indole (20). These results show that cyclization reactions of a 2-substituent toward the 3-position in naphthalene derivative are not suitable for preparing benz[f]indoles.
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石田 均司, 木下 俊也, 夏山 [リュウ]煥, 糠谷 東雄, 辻 邦郎, 小菅 貞夫, 山口 健太郎
1991 年 39 巻 12 号 p.
3153-3156
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
The crystal structures of anhydroscymnol (I) and scymnol (II), which were prepared from sodium scymnol sulfate (III) isolated from the bile of Rhizoprionodon acutus, have been determined by means of X-ray diffraction analyses. The crystals of I are orthorhombic, space group P2
12
12
1 with Z=4; unit-cell dimensions : a=13.562 (2), b=21.636 (2), c=8.735 (2) Å; II orthohombic, space group P2
12
12
1 with Z=4; unit-cell dimensions a=18.553 (2), b=19.887 (2), c=7.986(2) Å. Both structures, (24R, 25S)-(+)-24, 26-epoxy-5β-cholestane-3α, 7α, 12α, 27-tetrol (I) and (24R)-(+)-5β-cholestane-3α, 7α, 12α, 24, 26, 27-hexol (II), were solved from diffractometric data by direct methods and refined by least-squares calculations to R=0.073 (I) and R=0.062 (II) (2044 (I) and 2250 (II) observed independent significant reflections (I>3σ(I)), respectively. All the hydroxyl groups of both compounds are involved in a hydrogen-bonding network. The structure of III was determined to be (24R, 25S)-(+)-3α, 7α, 12α, 24, 26-pentahydroxy-5β-cholestan-27-yl sodium sulfate, based on the chemical data that alkaline degradation of III with aqueous potassium hydroxide gives only I.
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栗原 拓史, 寒川 愉美, 横出 佳代, 大石 宏文, 春沢 信哉, 米田 龍司
1991 年 39 巻 12 号 p.
3157-3162
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
The aldol condensation of the N-Boc-tetrahydro-β-carboline-1-acetate (4) with acrolein in the presence of lithium diisopropylamide (LDA) gave an allyl alcohol (6), which was then treated with methanesulfonyl chloride and triethylamine to give a mixture of the mesylate (8) (55%) and the indolopyrido-3, 5-oxyazin-4-one (10) (14%). When 8 was treated with 1, 8-diazabicyclo[5.4.0.]-7-undecene (DBU) in dimethylsulfoxide (DMSO) at room temperature, the azetopyridoindoles (12 and 13) were obtained unexpectedly. Alternative preparation of the indolopyrido-3, 5-oxazin-4-ones (15 and 16), which are stereoisomers of 10, from 6 followed by heating with DBU in DMSO gave several indoloquinolizidines (18, 19 and 20), which are key intermediates for the synthesis of the indole alkaloids vindolosine and vindoline.
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岡野 昌彦, 西村 尚文, 丸山 和美, 小坂 圭吾, 石橋 弘行, 池田 正澄
1991 年 39 巻 12 号 p.
3163-3167
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
(±)-D-Homocephalotaxine (2), an Unnatural analogue of cephalotaxine, has been synthesized by a synthetic sequence involving an acid-catalyzed cyclization of the α-sulfinylacetamide 8 as a key step.
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大倉 一枝, 関 興一, 寺島 正直, 金岡 祐一
1991 年 39 巻 12 号 p.
3168-3169
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
Direct photolyses of 2-halopyridine in various solvents afforded the corresponding ionic products, as well as the radical product pyridine, while 3- and 4-halopyridines produced pyridine exclusively. The formation of the ionic products may occur via the 2-pyridyl cation generated through the initial photo-included homolytic cleavage of the C-X bond followed by electron transfer within the resulting radical pair. The participation of the unshared pair of electrons adjacent to the radical carbon is suggested to be important for releasing the unpaired electron.
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川峯 勝巳, 竹内 理恵, 宮下 正昭, 入江 寛, 島本 啓子, 大船 泰史
1991 年 39 巻 12 号 p.
3170-3171
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
A synthesis of (-)-bursatellin has been accomplished by an application of a new procedure for oxidation at a benzylic position with K
2S
2O
8 to 1-acetoxy-2(S)-N-Boc-amino-3-(4-benzyloxyphenyl)propane as a key step.
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大谷 和弘, 相川 容子, 藤沢 良志子, 笠井 良次, 田中 治, 山崎 和男
1991 年 39 巻 12 号 p.
3172-3174
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
1, 4-α-Glucosylation at the 13-O-glycosyl moiety of stevioside (S) and rubusoside (RU) results in a significant increase of sweetness. Saponification of the 19-COO-β-glucosyl linkage of S and RU yielded steviolbioside (SB) (=13-O-β-sophorosyl-steviol) and steviolmonoside (SM) (=13-O-β-glucosyl-steviol), respectively, both of which are poorly soluble in an acetate buffer. It was found that the solubilities of SM and SB in the buffer solution were remarkably increased in the presence of γ-cyclodextrin (γ-CD). SB was solubilized in the buffer solution with the aid of γ-CD, and the solution was subjected to 1, 4-α-transglucosylation by using a cyclodextrin glucanotransferase-starch system to give a mixture of products which were glucosylated at the 13-O-glycosyl moiety. This mixture was acetylated, and the acetate was subjected to chemical β-glucosylation of 19-COOH followed by deacetylation to afford compounds which have superior sweetness to S. In the same way, derivatives with superior sweetness were selectively prepared from RU through SM.
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宮嶋 啓介, 竹元 万寿美, 阿知波 一雄
1991 年 39 巻 12 号 p.
3175-3179
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
6-Aza-5-oxo-2, 3, 4-trinor-1, 5-inter-m-phenylene protacyclin derivatives were synthesized by use of 1, 3-dipolar cycloaddition as a key step.
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長谷川 賀洋, 柳澤 利彦, 奥井 由佳, 佐藤 俊次, 穂坂 邦男, 陳 正雄, 三橋 博
1991 年 39 巻 12 号 p.
3180-3182
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
2, 4-Diamino-[E]-6-[2-(3-pyridyl)ethenyl]1, 3, 5-triazine (3a), leukotriene C
4 (LTC
4) antagonist, was found to possess a protective effect of HCl·ethanol-induced gastric lesions. Analogues of 3a were synthesized and evaluated for the effect as well as antagonistic activity against LTC
4-induced contraction. Seven compounds (3a-d, f-h) exhibited a potent protective effect on gastric lesions which was considered to be based on the antagonistic activity against LTC
4. The structure-activity relationships of the derivatives (3a-k) are discussed.
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沢田 誠吾, 松岡 俊一, 野方 健一郎, 永田 洋, 古田 富雄, 横倉 輝男, 宮坂 貞
1991 年 39 巻 12 号 p.
3183-3188
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
20(S)-Camptothecin derivatives having nitro, amino, chloro, bromo, hydroxyl and methoxyl groups in the A-ring were synthesized. B-Ring hydrogenated camptothecin (2a) was converted into 10-hydroxycamptothecin (6e) by treatment with lead tetraacetate in trifluoroacetic acid. 10-Substituted derivatives (6) were obtained by a photoreaction of N-oxides (9). The cytotoxicity o the A-ring modified camptothecins was evaluated against KB cells in vitro and leukemia L1210 in mice. 7-Ethyl-10-hydroxycamptothecin (6i) was identified as a potential derivative for further modification.
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佐藤 良也, 市橋 正晴, 奥村 和央
1991 年 39 巻 12 号 p.
3189-3201
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
The synthesis of new 1, 4-dihydropyridine derivatives containing novel substituent at the 2-position of the nucleus via the key intermediate 2-formyl-1, 4-dihydropyridines (X), is described. The aldehydes (X) were prepared by hydrolysis of the acetals (IX) which were obtained from aryl aldehyde (V) and alkyl 4, 4-dialkoxyacetoacetate (VI) by the Knoevenagel reaction and treatment with alkyl 3-aminocrotonate (VIII) according to the modified Hantzsch method. The formyl group of the aldehydes (X) was reactive enough to be converted to a variety of functional groups such as hydroxymethyl, cyano, substituted iminomethyl, carbamoyl, semicarbazone, substituted vinyl, ethynyl, and so on. In all of the novel compounds we prepared, 2-hydroxymethyl- and 2-cyano1, 4-dihydropyridines (IV and XXII) were found to possess potent activities in preliminary biological evaluations on hypotension in normotensive rats and on an increase in coronary blood flow in pentobarbital-anesthetized dogs. Optimization research in order to obtain a more potent compound was accomplished in the 2-hydroxymethyl- and 2-cyano-1, 4-dihydropyridine series. We selected isopropyl 2-cyano-3-methoxycarbonyl-4-(3-nitrophenyl)-6-methyl-1, 4-dihydropyridine-5-carboxylate. (XXIIj) as a candidate compound for further biological evaluation studies. Fortunately, XXIIj (nilvadipine) has been accepted in clinical use for the treatment of hypertensions.
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川島 豊, 佐藤 正和, 畑田 祐一, 五藤 准, 山根 裕子, 畑山 勝男
1991 年 39 巻 12 号 p.
3202-3206
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
A series of 3-acylidene-4-methylazetidine-2-one derivatives bearing various substituents at the 1-position of the azetidin-2-one ring was synthesized. These compounds were evaluated for platelet aggregation inhibitory activities. Most of the compounds synthesized showed potent inhibitory activities against rabbit platelet aggregation induced by adenosine diphosphate or collagen in vitro. Structure-activity relationships are also discussed.
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斉藤 眞, 片岡 茂博, 那須 綾子, 山次 信幸, 市川 厚
1991 年 39 巻 12 号 p.
3207-3210
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
A series of adenosine 3', 5'-cyclic monophosphoramidates (3, cAMP amidates), including long-chain alkyl amidates, were synthesized from adenosine 3', 5'-cyclic monophosphate (1, cAMP) by means of a one-pot reaction. THis reaction proceeded by the treatment of cAMP tributylammonium salt (2) with phosphorus pentachloride (PCl
5) and alkylamine in N, N-dimethylformamide (DMF). Compounds 3 synthesized were investigated to determine their cytotoxic activities on the growth of mouse mastocytoma P-815 cells, mouse manamary tumor FM3A cells, and human mammary tumor ZR-75 cells in culture. It was found that compounds 3h-m showed significant cytotoxic activities against these cell lines, and that cAMP decylamidate (3j) was the most cytotoxic compounds (the concentration required for 50% inhibition of cell growth, ID
50=6.0, 15.0, 2.2 μM, respectively); the antitumor effect on P-815 cells by a total packed cell volume method showed 81.8% inhibition. The cytotoxic activity of 3 increaesd with the increase in alkyl chain length up to 10 carbon atoms and decreased in compounds having longer alkyl chain.
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渡辺 紀代子, 福村 利光, 佐々木 茂貴, 前田 稔, 竹原 修造
1991 年 39 巻 12 号 p.
3211-3214
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
Aiming at the development of positron-emitting ligands with specific and high affinity toward dopamine D2 receptors in the central nervous system, we synthesized a new fluorinated eticlopride derivative. A fluorine atom was introduced at the C-4 position of the pyrrolidine ring of eticlopride, a dopamine D2 antagonist of the benzamide series. The in vitro binding affinity of this ligand toward the D2 receptor was found to be as potent as eticlopride, suggesting that the corresponding
18F-labelled compound may be useful as an in vivo radioligand for postron emission tomography.
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宮澤 修平, 岡野 和夫, 下村 直之, / 川原 哲也, 浅野 修, 吉村 寛幸, 宮本 光明, 佐久間 義範, 村本 賢三, 尾葉石 浩 ...
1991 年 39 巻 12 号 p.
3215-3220
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
A series of triazolodiazepines was synthesized and evaluated for anti-platelet activating factor (PAF) activities. Structure-activity relationship (SAR) studies on this series revealed that the introduction of a methyl group into the 8-position of the thienodiazepine nucleus can lead to a lengthening of the duration of action. Introduction of a methyl group produced an asymmetric center and the enantiomers so formed were separated with an optical resolving column. In the in vitro assay system, the (+)-isomers displayed 50-200 times more potent anti-PAF activity than the (-)-isomers. After comparison of toxicology and pharmacokinetics, (+)-6-(2-chlorophenyl)-3-cyclopropanecarbonyl-8, 11-dimethyl-2, 3, 4, 5-tetrahydro-8H-pyrido[4', 3' : 4, 5]thieno[3, 2-f][1, 2, 4]triazolo[4, 3-a][1, 4]diazepine (35(+)-isomer, E6123) was selected from among the compounds synthesized as a candidate for clinical study.
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久保寺 登, 宮本 勝仁, 秋山 正司, 松本 雅彦, 森 隆司
1991 年 39 巻 12 号 p.
3221-3224
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
Three vitamin D
3 analogues, 1α, 25-dihydroxy-23-oxavitamin D
3 (3), 1α, 25-dihydroxy-23-thiavitamin D
3 (4) and 1α, 25-dihydroxy-23-azavitamin D
3 (5) were synthesized. In the differentiation-inducing activity of human myeloid leukemia cells into macrophages in vitro, the 23-aza analogue (5) showed the least activity, while no remarkable differences were observed between the 23-oxa analogue (3) and the 23-thia analogue (4), which were less active than 1α, 25-dihydroxyvitamin D
3 (1).
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石原 雄二, 加藤 浩紀, 後藤 義一
1991 年 39 巻 12 号 p.
3225-3235
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
It has been suggested that the active site of acetylcholinesterase contains a hydrophobic binding site (HBS-1), which is closely adjacent to both the anionic and the esteratic sites. In this paper, we assumed that there exists another hydrophobic binding site (HBS-2), some distance removed from the anionic site. On this assumption, a new working hypothesis was proposed for the design of acetylcholinesterase inhibitors. A series of 2-[ω-[N-alkyl-N-(ω-phenyl-alkyl)amino]alkyl]-1H-isoindole-1, 3(2H)-diones was designed based on this hypothesis and tested for its inhibitory activities on acetylcholinesterase. Some in this series were revealed to be more potent than physostigmine. Optimum activity was found to be associated with a five carbon chain length separating the benzylamino group from the 1H-isoindole-1, 3(2H)-dione (phthalimide) moiety. Quantitative study of substitution effect on the phthalimide moiety revealed that hydrophilic and electron-withdrawing groups enhance the activity.
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石原 雄二, 加藤 浩紀, 後藤 義一
1991 年 39 巻 12 号 p.
3236-3243
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
A series of N-[ω-[N-phenylmethyl)amino]alkyl-3-arylpropenamides was prepared and tested for its inhibitory activities on acetylcholinesterase. Some in the series were found to be potent inhibitors. The structure-activity relationships were discussed in detail.
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日馬 恒雄, 曽我 恒彦, 小野 承行, 熊澤 栄治, 塩谷 恵美子, 中山 清, 魚戸 浩一, 長田 泰明
1991 年 39 巻 12 号 p.
3244-3253
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
Six novel lipid A analogs were synthesized. The first two analogs, 4 and 5, have an α-glycosidically bound carboxymethyl or 1, 3-dicarboxyisopropyl group on the disaccharide backbone with four tetradecanoyl groups. The next three analogs, 6, 7 and 8, have two or four N-dodecanoylglycyl groups on the 1-α-O-phosphonooxyethylated disaccharide backbone. Analog 6 bears N-dodecanoylglycyl groups on the hydroxyl functions at positions 3 and 3', and tetradecanoyl groups on the amino functions at positions 2 and 2'. Analog 7 is a 2, 3, 2' and 3'-tetrakis(N-dodecanoylglycyl) derivative, and analog 8 resembles compound 6, but the binding of the N-dodecanoylglycyl and tetradecanoyl groups at positions 2, 2' and 3, 3' are reversed. The third analog, 9, has the same acyl group conflguration as compound 6, but has a 1, 3-dicarboxyisopropyl group at position C-1. Compounds 4 and 5 exhibited definite antitumor activity against Meth A fibrosarcoma, indicating that the phosphate group at the C-1 position in lipid A could be replaced by the carboxylic acid without reducing the antitumor activity. In rabbits, compounds 6 and 9 exhibited potent antitumor activity, but their toxicity was extremely low. On the other hand, compounds 7 and 8 showed no antitumor activity. The levels of antitumor activity of 6 and 9 were similar to those of the natural-type lipid A. The antitumor activities of analogs with a N-dodecanoyglycyl group on the disaccharide backbone depended on the connecting sites of the acyl groups.
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北中 進, 滝戸 道夫
1991 年 39 巻 12 号 p.
3254-3257
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
Two novel flavones, torosaflavone C (1) and D (2), were isolated from the leaves of Cassis torosa Cav. The structures of 1 and 2 were established based upon spectral studies. Compound 1 displayed cytotoxic activity toward KB cells.
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矢原 正治, 小林 尚実, 泉谷 幸男, 野原 稔弘
1991 年 39 巻 12 号 p.
3258-3260
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
Capsicum species are very important plants used as vegetable foods, species and external medicines. In the preceding paper, we disclosed the occurrence of novel acylic diterpene glycosides from fruits of the Capsicum species. We now obtained three new acyclic diterpene glycosides, names capsianosides VI (1), G (2) and H (3), along with capsianosides II, A, B, C and D from the leaves and steam of the Capsicum annuum species, and their structures were elucidated by spectroscopic and chemical means.
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藁科 力, 宮瀬 敏男, 上野 明
1991 年 39 巻 12 号 p.
3261-3264
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
Five novel iridoid glycosides were isolated from the fresh whole plants of Verbascum thapsus L. (Scrophulariaceae). The structures of these iridoid glycosides were determined ont he basis of spectral and chemical evidence. These compounds were classified into two types : one iridoid glycosides contains ajugol, and the others contain 6-O-(α-L-rhamnopyranosyl)-catalpol in the structures.
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敦賀 朋子, 海老塚 豊, 中島 淳子, 秦 堯滔, 野口 博司, 飯高 洋一, 三川 潮
1991 年 39 巻 12 号 p.
3265-3271
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
The extracts of the flower buds of Magnolia salicifolia showed remarkable anti-allergy effects in passive cutaneous anaphylaxia (PCA) test. THe bioactive constituents of this medicinal drug were isolated by monitoring their activities with an in vitro bioassay system measuring inhibitory effects on induced histamine release from rat mast cells. Of the ten isolated compounds magnosalicin is a new compound of neolignan structure. In addition to the isolated compounds samples of coumarins and lignans were evaluated their biological activities with the in vitro bioassay.
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呉 金濱, 秦 堯滔, 海老塚 豊, 三川 潮
1991 年 39 巻 12 号 p.
3272-3275
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
Ether, methanol and aqueous extracts of Centipeda minima (Compositae) harbs were found to have significant anti-allergy activities in passive cutaneous anaphylaxis (PCA) test. Three flavonoids, two sesquiterpene lactones and an amide were isolated from this plant material as inhibitors to induced histamine release from mast cells. The sesquiterpenes were identified as isobutyroylplenolin and senecioylplenolin by spectral investigations. The flavonoids and sesquiterpenes exhibited significant anti-allergy activity in PCA test with p.o. administration.
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敦賀 朋子, 秦 堯滔, 海老塚 豊, 三川 潮
1991 年 39 巻 12 号 p.
3276-3278
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
Chloroform and methanol extracts of the fruits of Melaleuca lencadendron strongly inhibited histamine releaes from rat mast cells induced by compounds 48/80 or concanavalin A. Ursolic acid, a triterpene, was the most active compound contained in the chloroform extract and two stilbenes, piceatannol and oxyresveratrol, were isolated as active compounds from the methanol extract. Several other stillbenes and related compounds were examined to obtain information on the structure activity relationships of stilbenes.
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縄田 正志, 八木 隆行, 川鍋 康治, 田辺 信三
1991 年 39 巻 12 号 p.
3279-3282
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
We have developed a sensitive method for the measurement of rhodanese activity in human serum which is based on the colorimetric method for the determination of thiocyanate produced from methanethiosulfonate and cyanide as substrates. Thiocyanate gives a red complex with ferric ion in an acidic condition. THe present method is about 70-fold more sensitive than the conventional method using cyanide and thiosulfate as substrates and correlates well (r=0.997) with the conventional method in bovine liver rhodanese. Within-run precision of the method is 0.91% for 420 units/l serum adn teh calibration curve is linear up to 1850 units/l. The normal value for human serum, determined by the present method on 31 healthy persons, was 20.9±20.0 units/l (mean ±2S.D.). Rhodanese activity was clearly elevated in some serum samples which were observed at abnormal values in some biochemical diagnostic tests and showed significant positive correlations with guanase activity (r=0.728, p<0.01) and glutamic-oxalacetic transaminase activity (r=0.625, p<0.01).
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細田 宏, 長内 健, 南原 利夫
1991 年 39 巻 12 号 p.
3283-3286
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
The synthesis of the 3-glucuronides of 5α-cortol-20α, 5α-cortolone-20α and their 20β-epimers is described. The 5α-cortol 20, 21-diacetates (12, 17) and 5α-cortolone 20, 21-diacetates (14, 19) were the key intermediates. Sodium borohydride reduction of the carbonyl group at C-20 in 5α-tetrahydrocortisol 3-tert-butyldimethylsilyl ether 17, 21-acetonide (8) gate the 20α-hydroxy-acetonide (9). Selective removal of the acetonide ring was successful when the 20α-acetoxy-17α, 21-acetonide (10) was treated with 50% acetic acid. Subsequent acetylation with acetic anhydride in pyridine, followed by removal of the protecting group at C-3 in the silyl ether-acetate (11) gave the desired 20α-intermediate (12). The 11-ketone (14) was prepared from 11 by oxidation with pyridinium chlorochromate, followed by desilylation. The 20β-acetates (17, 19) were synthesized from 21-acetoxy-3α-11β, 17α-trihydroxy-5α-pregnan-20-one 3-tert-butyldimethylsily ether (15). Introduction of the glucuronyl residue at C-3 was carried out by means of the Koenigs-Knorr reaction.
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森田 哲生, 三上 史記, 金川 麻子, 世良 美佐紀, 植木 寛
1991 年 39 巻 12 号 p.
3287-3289
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
Vanadate stimulated the release of rat hepatic lipase activity from liver slices into an incubation medium in a time- and dose-dependent manner. Insulin, however, failed to have this stimulatory action, and the release by heparin was recognized, but was not additive to that by vanadate. Amiloride, an inhibitor of tyrosine kinase in some receptors and of the Na
+/H
+ exchange system suppressed the vanadate-stimulated releaes. Biochanin A, a different type of tyrosine kinase inhibitor than amiloride, also suppressed the effect of vanadate. HTe stimulation by vanadate was clearly preserved in Na
+-, K
+-, or Ca
2+-free medium, suggesting that neither the Na
+/H
+ exchange system, Na
+, K
+-adenosine triphosphatase, nor Ca
2+-influx into cells is involved in the action of this substance. These results suggest that vanadate-stimulated releaes of the enzyme activity is associated with the activation of the tyrosine kinase activity.
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柏倉 幾郎, 村上 美穂, 早瀬 幸俊, 高木 良成
1991 年 39 巻 12 号 p.
3290-3294
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
We have examined the effect of porcine kidney extract (PKE) on the growth of erythroid progenitor-derived colonies in a methylcellulose culture. The addition of PKE resulted in an enhancement of burst-forming-unit-erythroid (BFU-E)-derived colonies, and the enhancement of the colony was also observed in a low concentration of erythropoietin (Epo) and fetal calf serum (FCS). The activity of PKE on BFU-E was compared with the erythroid growth factors, such as recombinant murine interleukin-3 (IL-3), recombinant murine granulocyte/macrophage colony-stimulating factor (GM-CSF) and recombinant human granulocyte colony-stimulating factor (G-CSF) which are all well known to stimulate BFU-E growth. IL-3 showed a potent burst-promoting activity (BPA), but GM-CSF and G-CSF did not enhance BFU-E growth in our culture conditions. In the cultures supplemented with Epo, the rapid loss of BFU-E was prevented with IL-3; however, PKE alone did not prevent the disappearance of BFU-E. THese results suggest that PKE possesses a BPA-like activity which is considered an enhancement of BFU-E. These results suggest that PKE possesses a BPA-like activity which is considered an enhancement of BFU-E.
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大屋敷 孝雄, 安達 利恵, 松井 勝彦
1991 年 39 巻 12 号 p.
3295-3298
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
Treatment of lecithin liposomes with 100 μM ascorbic acid and 10 μM ferrous ion resulted in the formation of fluorescent products exhibiting an emission maximum at 430 nm and a decrease in the fluorescence intensity of 8-anilino-1-naphthalenesulfonate (ANS) bound to the liposomes without change in the emission maximum. The degree of ascorbic acid/Fe
2+-induced decrease in the ANS fluorescence was dependent on the extent of fluorescent product formation. The results of kinetic studies on ANS-binding to the liposomes showed that treatment of the liposomes with ascorbic acid/Fe
2+ causes an increases of the apparent dissociation constant (K
d) of ANS-liposome complex. This indicates that lipid peroxidation of the liposomes by treatment with ascorbinc acid/Fe
2+ decreases the binding affinity of ANS to the liposomes. In addition, it was also found that there is a good correlation between degrees of the K
d value and the formation of fluorescent products. The fluorescence properties, i.e. emission maximum and response of the fluorescence intensity for borohydride reduction, of the products formed by lipid peroxidation of the liposomes were simillar to those derived from modification of the liposomes wiht monofunctional aldehydes such as acetaldehyde and heptaldehyde. From these results, it is suggersted that the decrease of ANS-binding affinity to the liposomes by treatment with ascorbic acid/Fe
2+ may be due to changes in teh surface charge density of the liposomes relating to the formation of fluorescent products.
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加藤 真介, 緑上 淳一, 河野 弘幸, 大久保 恭仁
1991 年 39 巻 12 号 p.
3299-3302
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
We have demonstrated the internalization of epidermal growth factor (EGF) using membrane isolated from rat liver. The isolated membrane exhibited a saturation curve of the binding of
125I-EGF. Furthermore, competition between the bindign of
125I-EGF and unlabeled EGF to the isolated membrane was observed. These results were similar to those obtained from whole hepatocytes. In order to confirm whether or not the present experimental system using the isolated membrane can be used for the study of receptor-mediated endocytosis, the internalization of pre-bound EGF in the isolated membrane was assessed by two different methods. First, acid-insensitive
125I-EGF time-dependently increased following incubation at 37°C. Secondly, EGF became inaccessible to the exogenous
125I-anti-EGF antibody when under the same condition. These processes were dependent on adenosine triphosphate, but independent of Ca
2+ adn stimulated by guanosine triphophate. These results demonstrate that receptor-mediated endocytosis occurred in the isolated membrane.
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趙 春菊, 今村 理佐, 小橋 恭一
1991 年 39 巻 12 号 p.
3303-3306
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
Trace levels of urethane, a cancer causing chemical, were detected in many kinds of wine, sherry, whisky, brandy and sake. Urethane formation from urea and ethanol in sake can be prevented by the treatment of acid urease, which is produced by Lactobacillus fermentum, but urethane, once formed, is very difficult to decompose. In order to keep the safety of alcoholic beverages, enzymatic removal of urethane has become an urgent problem. We found that Bacillus licheniformis sp., isolated from mouse gastrointestine, decomposed urethane to ethanol and ammonia. The enzyme showed higher urethanase activity at an acidic condition than at a neutral condition, and was resistant against ethyl alcohol of high concentrations. However, the enzyme had a low affinity to urethane for the industrial removal of the compound from alcoholic beverages.
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本間 浩, 鎌倉 稔, 中込 泉, 松井 道夫
1991 年 39 巻 12 号 p.
3307-3312
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
An isoenzyme of phenol sulphotransferase, designated P-ST
G, was purified 157-fold from male rat liver cytosol by diethylaminoethyl-cellulose (DEAE-cellulose) and agarose-hexane-adenosine-3'-5'-bisphosphate affinity chromatography. The P-ST
G fraction obtained after DEAE-cellulose chromatrography rapidly lost its activity during storage at 4°C, however, the activity was recovered by the addition of 1.6M guanidine hydrochloride (Gndn HCl) followed by dialysis. Gndn HCl also substantially improved the yield of P-ST
G in a subsequent purification step using affinity chromatography, while the specific activity of the purified P-ST
G was not changed by Gndn HCl treatment. It is possible that the Gndn HCl treatment caused P-ST
G recovery from an inactivated to an active form rather than reactivating it for increased activity. Purified P-ST
G is a homodimer with a native molecular mass of 67kDa; the subunit molecular mass is 35kDa. Immunoblot analysis carried out with antibodies raised against the purified enzyme indicated that male rat liver contains a higher level of the enzyme than female rat liver. This enzyme is also expressed in the kidney and the atomach. P-ST
G reaches maximum activity when 1-naphthol, 2-naphthol and 4-nitrophenol are used as substrates at pH 5.5. Using dopamine as a substrate the pH optimum is about 9.0. P-ST
G activity is markedly inhibited by the addition of sodium chloride to the reaction mixture.
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福岡 英平, 牧田 みどり, 山村 重雄
1991 年 39 巻 12 号 p.
3313-3317
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
An X-ray powder diffraction method was presented to evaluate the preferred orientation of crystallites in tablets by using transmission and reflection techniques. In the present method, the X-ray diffraction intensities of the hkl reflections were measured with particular geometrical arrangements of the x-ray source, sample and detector so as to permit the measurement of diffraction intensities from the particular hkl planes oriented at various angles within the tablet. Thus, the preferred orientation plane was evaluated by comparing the observed intensities with the theoretical intensities calculated from the crystal structure factors.Aspirin, salicylic acid, benzoic acid and nicotinic acid were used as samples. In all samples, it was found that the crystallites had a preferred orientation in the tablet. The 100 plane in aspirin, the 110 or 210 plane in salicylic acid, the 002 plane in benzoic acid and the 002 plane in nicotinic aicd, had a tendency to orient parallel to the upper surface of the tablet during compression.
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石野 隆三, 吉野 廣祐, 平川 善行, 野田 和夫
1991 年 39 巻 12 号 p.
3318-3322
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
In order to characterize the force-dependence of the consolidation behavior and drug release properties of wax matrix tablets, granules consisting of isoniazid and hydrogenated castor oil (80 : 20) were compressed at various compression force, then the compacts obtained were tested for various properties including tablet density, crushing force and dissolution rate. The packing fraction increased with increasing compression force and reached a constant level (0.973) at a force above 1273 kg/cm
2. The tensile strength of the compacts increased with the increase of the packing fraction, but it continued to increase slightly even after the packing fraction held at an almost constant value. Although the matrix structure became tighter with increasing compression force, the drug release rate from the tablet noticeably increased. Theoretical analysis of this seemingly extraordinary phenomenon provides a reasonable explanation in which the void space left after compression could not work as an effective water channel during dissolution due to the poor wettability of the matrix material. Also, the force-dependence of the disorder in the internal structure of the tablets was examined on the basis of the two-direction dissolution rate analysis. As a result, it was found that the internal disorder increased with increasing compression force, and when the compression force exceeded 1273 kg/cm
2, the disorder was considerably extended.
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黒野 幸久, 渓 英敏, 桑山 知成, 畑野 研一郎, 八代 有, 池田 憲
1991 年 39 巻 12 号 p.
3323-3326
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
Ring-opening and ring-closing (acid-base equilibrium) reactions of the six-membered oxazine of benzodiazepinoxazines (BZINs) and the subsequent hydrolyses of the diazepine ring have been investigated kinetically and compared with the reactions of benzodiazepinooxazoles (BZOLs) which have the five-membered oxazolidine ring. The ring-closing reaction for BZINs is slower than that for BZOLs due to the increase in the degree of freedom for the moving molety of BZINs. The rates of the ring-opening reactions are almost independent of the substituents at 12b-position (H-(1), CH
3-(2), and C
6H
5-(3)), indicating that an attacking proton may approach equally (non-sterically) to the lone pair of N
5 atoms. Possible conformational aspects of BZINs in solution are proposed. Cleavages (hydrolyses) of the diazepine ring occur at the C
12b-N
5 (iminium) bond for 2 and 3 and are 10-100 times faster than those for the corresponding BZOLs. For 1, in contrast to 2 and 3, hydrolysis of the amide bond (N
8-C
7) of the diazepine ring takes place instead of the iminium bond, similar to the case of 11b-hydrogen BZOL.
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木全 秀樹, 中島 勝明, 鈴木 秀雄, 小出 高志, 山本 進, 成田 勉
1991 年 39 巻 12 号 p.
3327-3330
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
To study the thrombolytic effect of tissue plasminogen activator (t-PA) on cerebral emboli, we characterized cerebral embolization in stroke-prone spontaneously hypertensive rats (SHRSPs) and Wistar Kyoto rats (WKYs).[
125I]Fibrin clot particles (20-100 μm diameter) were injected twice at an interval of 90 min into the left internal carotid artery of WKYs and SHRSPs. After each injection, spontaneous embolus dissolution was monitored with a γ-ray detector placed on the head of the embolic rats. Embolus dissolution was spontaneously generated in 15 min after the injection of fibrin clots. In WKYs, 21% and 42% of the clots were dissolved 30 and 90 min after the second embolization, respectively. On the other hand, the spontaneous embolus dissolution in SHRSPs was significantly lower than that of WKYs, indicating that the endogenous fibrinolytic ability of SHRSPs is less potent than that of normotensive rats. The intravenous administration of t-PA at doses of 75, 250 and 750 μg/kg caused a dose-dependent embolus dissolution in SHRSPs. Furthermore, systemically applied t-PA produced embolus dissolution without causing systemic plasminogen activation, fibrinogen breakdown or bleeding.In conclusion, the intravenous administration of t-PA produces selective embolus dissolution without systemic fibrino(geno)lysis in a cerebral embolic SHRSP.
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石井 克幸, 畠中 稔, 植田 育男
1991 年 39 巻 12 号 p.
3331-3334
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
The Smiles rearrangement of 2-(1-methyl-1H-tetrazol-5-ylthio)acetamides and their sulfonyl derivatives occurred under basic conditions to yield 5-amino-1-methyl-1H-tetrazole derivatives in excellent yields.
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猪野 宣人, / 山門 理恵子, 森崎 益雄, 古川 洋司, 畠 忠, Tadashi HATA
1991 年 39 巻 12 号 p.
3335-3337
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
Reaction of 19-hydroxycholest-4-en-3-one (1) with diethylaminosulfur trifluoride (DAST) in acetonitrile at reflux gave 10β-fluoro-5, 1-seco-5, 19-cyclocholest-4-en-3-one (2) in 60% yield. Analogous reaction of androstane derivatives afforded the corresponding bicyclo[4.4.1] compounds 6 and 8. Under milder reaction conditions, the diethylaminosulfnate 3 was secured in 20% yield from 1.
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/ 中尾 典義, 橋垣 国子, 竹内 靖雄, 大和 正利, Masatoshi YAMATO
1991 年 39 巻 12 号 p.
3338-3340
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
Tetrahydro-β-carbolines, (S)-tetrahydroharman (8a) and (S)-1-phenyltetrahydro-β-carboline (8b), were asymmetrically synthesized starting from (R)-phenylglycinol and 1-benzyl-3-(2-bromoethyl)indole (1). Asymmetric synthesis of the 9-thio analogue (15) of 8a was also achieved.
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長 秀連, 岩下 孝, 浜口 美樹子, 小山 嘉晃
1991 年 39 巻 12 号 p.
3341-3342
発行日: 1991/12/25
公開日: 2008/03/31
ジャーナル
フリー
The C-13 long-range selective proton decoupling method and x-ray crystallographic analysis were employed to determine the stereochemistry of the caffeic acid derivatives, extremely potent 12-lipoxygenase inhibitors, synthesized from cyanoacetates and aromatic aldehydes. The ester group of 1 and 2 was found to be trans to the phenyl group.
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