著者
岡本 好一 八重樫 隆志
出版者
日本線虫学会
雑誌
日本線虫研究会誌 (ISSN:03882357)
巻号頁・発行日
vol.10, pp.35-42, 1981

1) 本邦産の主な<I>Meloidogyne</I> 6種について, 第2期幼虫の正面像をSEMで比較検討した。<BR>2) labial discととmedial lipは各種とも融合し, その形状は<I>M.Javanica</I>以外の5種はいずれも唖鈴型 (dumbbell-shaped) で, <I>M.incognita, M.arenaria, M.mali</I>および<I>M.camelliae</I>で大きく, <I>M.hapla</I>で小さい。lateral lipとmedial lipの接合は, labial discの側端に垂直である。<I>M.javanica</I>では蝶ネクタイ型 (bowtie-shaped) で, lateral lipとmedial lipの接合はlabial discの側端に鈍角である。<BR>3) cephalic sensillumは<I>M. hapla</I>と<I>M. camelliae</I>で不明瞭であったが, 他種では認められた。<BR>4) lateral lipの形状は, <I>M. incognita</I>と<I>M. arenaria</I>が丸く, 長く, <I>M.hapla</I>は丸く, 短い。<I>M.javanica</I>と<I>M.mali</I>は大きく, medial lipの側端よりもつき出し, その形状はM.jamnicaでは三角形, M.maliでは丸味を帯びる。<BR>5) head regionの体環の有無については, <I>M.incognita</I>の供試populationでは不規則かつ不完全ながら体環が認められたが, 他の種類では認め得なかった。<BR>6) 以上の結果から, 供試した本邦産6種の<I>Meloidogyne</I>の第2期幼虫の正面像は, 種によってそれぞれ異なり, そのうち4種の特徴はEisenback and Hirschmann3) の記述とほぼ一致し, SEMによる正面像の観察で種の識別が可能と認められた。
著者
藤田 靖之 八重樫 隆 澤田 誠吾 尾山 廣 芳本 忠 鶴 大典
出版者
The Pharmaceutical Society of Japan
雑誌
Biological and Pharmaceutical Bulletin (ISSN:09186158)
巻号頁・発行日
vol.18, no.5, pp.648-652, 1995-05-15 (Released:2008-04-10)
参考文献数
22
被引用文献数
5 5

A hydrolytic enzyme which catalyzes hydrolysis of the ester-linkage of a series of 17-O-acyl derivatives of 7-ethylcamptothecin-21-(2-dimethylamino) ethylamide [acyl derivatives of 22E] was purified from rat liver and its properties were characterized. It hydrolyzed the ester-linkage of all 22E derivatives tested as well as p-nitrophenyl acetate at pH 8-9 but had no effect on 7-ethyl-10-[4-(piperidino)-1-piperidino] carbonyloxycamptothecin (CPT-11 : irinotecan), unlike CPT-11 converting carboxylesterase, which was previously purified from rat serum [Tsuji T. et al., J. Pharmacobio-Dyn., 14, 341 (1991)]. The enzyme had no effect on either acetyl choline or butyrylcholine. It was inhibited by several organophosphorous compounds such as diisopropyl fluorophosphate (DFP), bis-(pnitrophenyl) phosphate and paraoxon, but was insensitive to inhibitors specific for choline esterases. These results indicate that this liver esterase is clearly distinct from choline esterase and serum CPT-11 converting enzyme and is able to convert pro-drugs, O-acyl derivatives of 22E, to an antitumor agent.
著者
沢田 誠吾 八重樫 隆 古田 富雄 横倉 輝男 宮坂 貞
出版者
The Pharmaceutical Society of Japan
雑誌
Chemical and Pharmaceutical Bulletin (ISSN:00092363)
巻号頁・発行日
vol.41, no.2, pp.310-313, 1993-02-15 (Released:2008-03-31)
参考文献数
22
被引用文献数
13 20

7-Ethylcamptothecin (1d), a model which does not have any site on the A-ring for further modification was converted into water-soluble derivatives by opening the E-ring lactone. 1d was heated in N, N-dimethylenediamine to yield amide 2a, and this was then acylated to furnish 3a-q, which were soluble in water as their HCl salts. The propionyl (3b), butyryl (3c) and methylthiopropionyl (3h) derivatives showed higher activity than the sodium salt of 1d. The acyl group makes the derivatives more lipophilic, and ease of hydrolysis of amide 2a to 1d is thought to be necessary for significant activity.
著者
八重樫 隆 沢田 誠吾 古田 富雄 横倉 輝男 山口 健太郎 宮坂 貞
出版者
The Pharmaceutical Society of Japan
雑誌
Chemical and Pharmaceutical Bulletin (ISSN:00092363)
巻号頁・発行日
vol.41, no.5, pp.971-974, 1993-05-15 (Released:2008-03-31)
参考文献数
10
被引用文献数
6 10

The structure of the N-amino pyridone (4a) obtained by the reaction of camptothecin (1a) with hydrazine was determined by X-ray crystallography. A mixture of 7-etylcamptothecin (1b) and hydrazine hydrate was stirred at room temperature, and the hydrazide (2b) was isolated as its diacetate 2c. Treatment of the 17-O-acetyl amide (5a) with hydrazine gave 1b (74% yield) and the N-amino lactam 6 (11% yield). Compounds with bulky acyl groups, 5c-e, gave 6 in modest yields. The N-amino lactam 6 was smoothly dehydrated into the pyridone 4d by refluxing in hydrazine hydrate.
著者
八重樫 隆 野方 健一郎 沢田 誠吾 古田 富雄 横倉 輝男 宮坂 貞
出版者
The Pharmaceutical Society of Japan
雑誌
Chemical and Pharmaceutical Bulletin (ISSN:00092363)
巻号頁・発行日
vol.40, no.1, pp.131-135, 1992-01-25 (Released:2008-03-31)
参考文献数
19
被引用文献数
9 10

Water-soluble derivatives having the lactone ring intact were synthesized starting from 7-ethyl-10-hydroxycamptothecin (1). Glycosides (2) of the phenolic hydroxyl group of 1 were obtained by reaction with acetylated α-bromosugars in acetone or aqueous acetone in the presence of potassium carbonate, followed by deprotection.Phosphates (3) were prepared by reaction of 1 with phosphoryl chloride in pyridine or with dibenzylchlorophosphoridate.Sulfates (4) were obtained by reaction of 1 with sulfur trioxide-pyridine complex in the presence of a tertiary amine.The organic ammonium salts of monophosphate (3p) and sulfates (4a and 4b) showed significant activity against L1210 in vivo.
著者
八重樫 隆 野方 健一郎 沢田 誠吾 古田 富雄 横倉 輝男 宮坂 貞
出版者
公益社団法人日本薬学会
雑誌
Chemical & pharmaceutical bulletin (ISSN:00092363)
巻号頁・発行日
vol.40, no.1, pp.131-135, 1992-01-25

Water-soluble derivatives having the lactone ring intact were synthesized starting from 7-ethyl-10-hydroxycamptothecin (1). Glycosides (2) of the phenolic hydroxyl group of 1 were obtained by reaction with acetylated α-bromosugars in acetone or aqueous acetone in the presence of potassium carbonate, followed by deprotection.Phosphates (3) were prepared by reaction of 1 with phosphoryl chloride in pyridine or with dibenzylchlorophosphoridate.Sulfates (4) were obtained by reaction of 1 with sulfur trioxide-pyridine complex in the presence of a tertiary amine.The organic ammonium salts of monophosphate (3p) and sulfates (4a and 4b) showed significant activity against L1210 in vivo.
著者
沢田 誠吾 八重樫 隆 古田 富雄 横倉 輝男 宮坂 貞
出版者
公益社団法人日本薬学会
雑誌
Chemical & pharmaceutical bulletin (ISSN:00092363)
巻号頁・発行日
vol.41, no.2, pp.310-313, 1993-02-15

7-Ethylcamptothecin (1d), a model which does not have any site on the A-ring for further modification was converted into water-soluble derivatives by opening the E-ring lactone. 1d was heated in N, N-dimethylenediamine to yield amide 2a, and this was then acylated to furnish 3a-q, which were soluble in water as their HCl salts. The propionyl (3b), butyryl (3c) and methylthiopropionyl (3h) derivatives showed higher activity than the sodium salt of 1d. The acyl group makes the derivatives more lipophilic, and ease of hydrolysis of amide 2a to 1d is thought to be necessary for significant activity.
著者
八重樫 隆 沢田 誠吾 永田 洋 古田 富雄 横倉 輝男 宮坂 貞
出版者
公益社団法人 日本薬学会
雑誌
CHEMICAL & PHARMACEUTICAL BULLETIN (ISSN:00092363)
巻号頁・発行日
vol.42, no.12, pp.2518-2525, 1994
被引用文献数
42

Twenty-six novel A-ring-modified 7-ethylcamptothecins (6) were synthesized by Friedlander's condensation of the chiral tricyclic ketone (5) with aminopropiophenones (4). The compounds substituted with fluorine at the 11 position showed strong cytotoxicity to KB and L1210 cells. The 11-fluoro derivatives also exhibited strong inhibitory activity on DNA topoisomerase I. Nine compounds 6 with four to ten times stronger cytotoxicity than that of camptothecin were selected and converted into water-soluble 17-O-acyl amide derivatives (8). Compounds 8e (10-Me, O-COCH<SUB>2</SUB>CH<SUB>2</SUB>SCH<SUB>3</SUB>) and 8f (11-F, O-COC<SUB>2</SUB>H<SUB>5</SUB>) showed activity towards Meth A in mice that was comparable to that of CPT-11, at lower doses than CPT-11.
著者
八重樫 隆 沢田 誠吾 永田 洋 古田 富雄 横倉 輝男 宮坂 貞
出版者
公益社団法人日本薬学会
雑誌
Chemical & pharmaceutical bulletin (ISSN:00092363)
巻号頁・発行日
vol.42, no.12, pp.2518-2525, 1994-12-15

Twenty-six novel A-ring-modified 7-ethylcamptothecins (6) were synthesized by Friedlander's condensation of the chiral tricyclic ketone (5) with aminopropiophenones (4). The compounds substituted with fluorine at the 11 position showed strong cytotoxicity to KB and L1210 cells. The 11-fluoro derivatives also exhibited strong inhibitory activity on DNA topoisomerase I. Nine compounds 6 with four to ten times stronger cytotoxicity than that of camptothecin were selected and converted into water-soluble 17-O-acyl amide derivatives (8). Compounds 8e (10-Me, O-COCH_2CH_2SCH_3) and 8f (11-F, O-COC_2H_5) showed activity towards Meth A in mice that was comparable to that of CPT-11,at lower doses than CPT-11.