研究者詳細 - 佐々木　健二

MISC - 佐々木　健二

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Polycyclic N-Heterocyclic Compounds. Part 85: Synthesis and Evaluation of Antiplatelet Aggregation Activity of 2,4-Disubstituted 5,6-Dihydro[1]benzazepino[5,4-d]pyrimidine and Related Compounds

Kensuke Okuda, Ying-Xue Zhang, Takashi Hirota, Kenji Sasaki

JOURNAL OF HETEROCYCLIC CHEMISTRY 52 ( 3 ) 888 - 895 2015年5月

記述言語：英語出版者・発行元：WILEY-BLACKWELL

We have synthesized a large number of tricyclic 2-substituted 4-alkylamino-5,6-dihydro[1]benzazepino[5,4-d]pyrimidines as part of our research to develop new effective antiplatelet drugs. A variety of alkyl and aryl groups were used as substituents at the 2-position. Evaluation of the effects of the newly synthesized compounds on collagen-induced platelet aggregation revealed several promising antiplatelet candidates with potencies superior to aspirin.

DOI： 10.1002/jhet.2040

Polycyclic N-Heterocyclic Compounds. Part 86: Synthesis and Evaluation of Antiplatelet Aggregation Activity of 2,4-Disubstituted 9-Chloro-5,6-dihydropyrimido[5,4-d]benzazepine and Related Compounds

Kensuke Okuda, Shigeki Takarada, Takashi Hirota, Kenji Sasaki

JOURNAL OF HETEROCYCLIC CHEMISTRY 52 ( 3 ) 780 - 792 2015年5月

記述言語：英語出版者・発行元：WILEY-BLACKWELL

Libraries of tricyclic 2-substituted 4-alkylamino-9-chloro-5,6-dihydropyrimido[5,4-d]benzazepines and tetracyclic 12-substituted 8-chloro-1,2,5,6-tetrahydro-4H-imidazo[1,2:1,6]pyrimido[5,4-d]benzazepines were synthesized as part of our research to develop new effective antiplatelet drugs. Several alkyl and aryl groups were used as substituents at the 2-position. Evaluation of the effects of the newly synthesized compounds on collagen-induced platelet aggregation revealed several promising antiplatelet candidates with potencies superior to aspirin.

DOI： 10.1002/jhet.2190

SYNTHESIS, BIOLOGICAL ACTIVITIES, AND TAUTOMERISM OF 4-QUINOLONES AND RELATED COMPOUNDS

Yoshihisa Kurasawa, Kenji Sasaki

HETEROCYCLES 91 ( 1 ) 1 - 39 2015年1月

記述言語：英語掲載種別：書評論文，書評，文献紹介等出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD

This review describes the synthesis, biological activities, and tautomerism of various 4-quinolones together with related compounds including 4-oxopyridazino[3,4-b]quinoxalines (bioisostere of 4-quinolones).

DOI： 10.3987/REV-14-806

Quinolone Analogs 16: A Facile D-H Exchange for 3-H Proton of 2-Substituted 4-Quinolones in Acidic Media

Yoshihisa Kurasawa, Kiminari Yoshida, Naoki Yamazaki, Kenji Sasaki, Yoshito Zamami, Zhao Min, Atsumi Togi, Hideyuki Ito, Eisuke Kaji, Haruhiko Fukaya

JOURNAL OF HETEROCYCLIC CHEMISTRY 51 ( 6 ) 1821 - 1829 2014年11月

記述言語：英語出版者・発行元：WILEY-BLACKWELL

The 4-quinolones having the urea or carbamate moiety at the 2-position showed the facile deuterium-hydrogen (D-H) exchange of the 3-H proton in deuteriotrifluoroacetic acid-deuteriodimethyl sulfoxide (3:1) at 60 degrees C, whereas the 4-quinolones possessing the carboxylate or carbohydrazide group at the 2-position and 2-substituted 4-methoxyquinolines represented no D-H exchange of the 3-H proton under the same condition. The aforementioned D-H exchange was found to require both the tautomerization of the 4-quinolone into 4-hydroxyquinoline in strongly acidic media and the nitrogen functional group at the 2-position.

DOI： 10.1002/jhet.1933

Quinolone Analogs 13: Synthesis of Novel 1,1 '-(2-Methylenepropane-1,3-diyl)di(4-quinolone-3-carboxylate) and Related Compounds

Yoshihisa Kurasawa, Kiminari Yoshida, Naoki Yamazaki, Eisuke Kaji, Kenji Sasaki, Yoshito Zamami, Takatoshi Fujii, Min Zhao, Hideyuki Ito, Haruhiko Fukaya

JOURNAL OF HETEROCYCLIC CHEMISTRY 51 ( 6 ) 1720 - 1726 2014年11月

記述言語：英語出版者・発行元：WILEY-BLACKWELL

The reaction of the 4-hydroxyquinoline-3-carboxylate 6 with pentaerythritol tribromide gave the 1,1-(2-methylenepropane-1,3-diyl)di(4-quinolone-3-carboxylate) 11, whose reaction with bromine afforded the 1,1-(2-bromo-2-bromomethylpropane-1,3-diyl)di(4-quinolone-3-carboxylate) 12. Compound 12 was transformed into the (Z)-1,1-(2-acetoxymethylpropene-1,3-diyl)di(4-quinolone-3-carboxylate) 13 or (E)-1,1-[2-(imidazol-1-ylmethyl)propene-1,3-diyl]di(4-quinolone-3-carboxylate) 14. Hydrolysis of the dimer (Z)-13 or (E)-14 with potassium hydroxide provided the (E)-1,1-(2-hydroxymethylpropene-1,3-diyl)di(4-quinolone-3-carboxylic acid) 15 or (Z)-1,1-[2-(imidazol-1-ylmethyl)propene-1,3-diyl]di(4-quinolone-3-carboxylic acid) 16, respectively. The nuclear Overhauser effect (NOE) spectral data supported that those hydrolysis resulted in the geometrical conversion of (Z)-13 into (E)-15 or (E)-14 into (Z)-16.

DOI： 10.1002/jhet.1861

Polycyclic N-Heterocyclic Compounds. Part 79: Synthesis of 2,4-Disubstituted 6,7-Dihydro-5H-benzo[6,7]cyclohepta[1,2-d]pyrimidines as Potential Antiplatelet Aggregators

Kensuke Okuda, Takashi Hirota, Kenji Sasaki

JOURNAL OF HETEROCYCLIC CHEMISTRY 51 ( 6 ) 1607 - 1614 2014年11月

記述言語：英語出版者・発行元：WILEY-BLACKWELL

Libraries of tricyclic 2-substituted 4-alkylamino-6,7-dihydro-5H-benzo[6,7]cyclohepta[1,2-d]pyrimidines were synthesized as part of our research to develop new effective antiplatelet drugs. Several alkyl and aryl groups were used as substituents at the 2-position. Evaluation of the effects of the newly synthesized compounds on collagen-induced platelet aggregation revealed several promising antiplatelet candidates with potencies superior to aspirin.

DOI： 10.1002/jhet.1714

Quinolone Analogues 15: Synthesis and Antimalarial Activity of 4-Phenyl-1-(1-triazolylmethyl-4-quinolon-3-ylcarbonyl)semicarbazide and Related Compounds

Yoshihisa Kurasawa, Kiminari Yoshida, Naoki Yamazaki, Kenji Sasaki, Yoshito Zamami, Zhao Min, Atsumi Togi, Hideyuki Ito, Eisuke Kaji, Haruhiko Fukaya

JOURNAL OF HETEROCYCLIC CHEMISTRY 51 ( S1 ) E249 - E254 2014年8月

記述言語：英語出版者・発行元：WILEY-BLACKWELL

The 1-hydrazinocarbonylmethyl-4-quinolone-3-carboxylate (10) was converted into the 1-(4-amino-1,2,4-triazol-3-ylmethyl)-4-quinolone-3-carboxylic acid (13), whose reaction with arylcarbaldehydes gave the 1-(4-arylmethyleneamino-1,2,4-triazol-3-ylmethyl)-4-quinolone-3-carboxylic acids (5a, 5b, 5c, 5d, 5e, 5f, 5g). Compound 10 was also transformed into the 1-(4-amino-1,2,4-triazol-3-ylmethyl)-4-quinolone-3-carbohydrazide (15), whose reaction with phenyl isocyanate or phenyl isothiocyanate afforded the 4-phenyl-1-(1-triazolylmethyl-4-quinolon-3-ylcarbonyl)semicarbazide (6a) or 4-phenyl-1-(1-triazolylmethyl-4-quinolon-3-ylcarbonyl)thiosemicarbazide (6b), respectively. Compounds 6a, 6b showed the in vitro antimalarial activity to chloroquine-resistant Plasmodium falciparum, wherein their IC50 was 3.89 and 3.91 mu M, respectively.

DOI： 10.1002/jhet.1822

Polycyclic N-Heterocyclic Compounds. Part 80: Synthesis and Evaluation of Effects on In Vitro Pentosidine Formation of 5,6-Dihydro[1]benzothieno [3 ',2 ':2,3]thiepino[4,5-d]pyrimidine and Related Compounds

Kensuke Okuda, Yutaka Itsuji, Takashi Hirota, Kenji Sasaki

JOURNAL OF HETEROCYCLIC CHEMISTRY 51 ( 4 ) 891 - 898 2014年7月

記述言語：英語出版者・発行元：WILEY-BLACKWELL

Reaction of 3-(3-cyanopropylthio)[1]benzothiophene-2-carbonitrile with tert-BuONa gave 5-amino-1,2-dihydro[1]benzothieno[3,2-d]thieno[2,3-b]pyridine and 5-amino-2,3-dihydro[1]benzothieno[3,2-b]thiepin-4-carbonitrile. The latter compound served as a convenient scaffold for the synthesis of the new heterocycles, [1]benzothieno[3,2:2,3]thiepino[4,5-d]pyrimidines. All of our new tetracyclic products were evaluated for in vitro inhibitory activity on the formation of pentosidine, which is one of representative advanced glycation end products.

DOI： 10.1002/jhet.1709

Polycyclic N-Heterocyclic Compounds. Part 82: Synthesis and Evaluation of Anti-Platelet Aggregation Activity of 2,4-Disubstituted 5,6-Dihydro[1]benzothiepino[5,4-d]pyrimidine and Related Compounds

Kensuke Okuda, Takashi Hirota, Kenji Sasaki

JOURNAL OF HETEROCYCLIC CHEMISTRY 51 ( 4 ) 911 - 920 2014年7月

記述言語：英語出版者・発行元：WILEY-BLACKWELL

We have synthesized a large number of tricyclic 2-substituted 4-alkylamino-5,6-dihydro[1]benzothiepino[5,4-d]pyrimidines as part of our research to develop new effective anti-platelet drugs. A variety of alkyl and aryl groups were used as substituents at the 2-position. Evaluation of the effects of the newly synthesized compounds on collagen-induced platelet aggregation revealed several promising anti-platelet candidates with potencies superior to aspirin.

DOI： 10.1002/jhet.1741

Polycyclic N-Heterocyclic Compounds. Part 75: Synthesis of 2,4-Disubstituted 5,6-dihydro[1]benzoxepino[5,4-d]pyrimidines and 12-Substituted 1,2,4,5-Tetrahydro[1]benzoxepino[4,5-e]imidazo[1,2-c]pyrimidines as Potential Antiplatelet Aggregators

Kensuke Okuda, Yuko Yamamoto, Takashi Hirota, Kenji Sasaki

JOURNAL OF HETEROCYCLIC CHEMISTRY 51 ( 4 ) 972 - 981 2014年7月

記述言語：英語出版者・発行元：WILEY-BLACKWELL

Libraries of tricyclic 2-substituted 4-alkylamino-5,6-dihydro[1]benzoxepino[5,4-d]pyrimidines and tetracyclic 12-substituted 1,2,4,5-tetrahydro[1]benzoxepino[4,5-e]imidazo[1,2-c]pyrimidines were synthesized as part of our research to develop new effective antiplatelet drugs. Several alkyl and aryl groups were used as substituents at the 2-position. Evaluation of the effects of the newly synthesized compounds on collagen-induced platelet aggregation revealed several promising antiplatelet candidates with potencies superior to aspirin.

DOI： 10.1002/jhet.1559

Polycyclic N-heterocyclic compounds. Part 83. Synthesis of 2,4-disubstituted 5,6-dihydro[1]benzofuro[3',2':2,3]oxepino[4,5-d]pyrimidines and 2,4,5-trisubstituted 5,6-dihydro[1]benzofuro[2',3':5,6]pyrano[4,3-d]pyrimidines from 4-chloro-5,6-dihydro[1]ben・・・

Kensuke Okuda, Jun-ichi Takano, Takashi Hirota, Kenji Sasaki

Journal of Heterocyclic Chemistry 51 ( 3 ) 788 - 793 2014年5月

Polycyclic N-Heterocyclic Compounds 76: Synthesis and Antiplatelet Evaluation of 2,4-Disubstituted 5,6-Dihydro[1]benzofuro[3',2':2,3]oxepino[4,5-d]pyrimidines

Kensuke Okuda, Jun-ichi Takano, Takashi Hirota, Kenji Sasaki, Yuta Nishina, Hiroyuki Ishida

JOURNAL OF HETEROCYCLIC CHEMISTRY 51 ( 3 ) 661 - 668 2014年5月

記述言語：英語出版者・発行元：WILEY-BLACKWELL

Reaction of several Vilsmeier reagents with 5-amino-2,3-dihydro[1]benzofuro[3,2-b]oxepin-4-carbonitrile gave tetracyclic 2-substituted 4-chloro-5,6-dihydro[1] benzofuro[3',2':2,3]oxepino[4,5-d]pyrimidines. The structure of one of these, the 4-chloro-2-phenyl derivative, was confirmed by X-ray crystallography. Treatment of the 4-chloro derivatives with simple amines as nucleophile afforded 2-substituted 4-amino derivatives. A pentacyclic compound was also obtained by dehydrative ring closure. These products were evaluated for antiplatelet activity, and some showed potency comparable with that of aspirin.

DOI： 10.1002/jhet.1539

Polycyclic N-Heterocyclic Compounds. Part 78: Synthesis of N-[2-([1,2,4] Oxadiazol-5-yl) cyclohepten-1-yl]formamide Oximes and Their Evaluation as Inhibitors of Platelet Aggregation

Kensuke Okuda, Ying-Xue Zhang, Takashi Hirota, Kenji Sasaki

JOURNAL OF HETEROCYCLIC CHEMISTRY 51 ( 2 ) 518 - 522 2014年3月

記述言語：英語出版者・発行元：WILEY-BLACKWELL

N-[2-([1,2,4]Oxadiazol-5-yl)cyclohepten-1-yl]formamide oximes were synthesized by fusion of (6,7,8,9-tetrahydro-5H-cyclohepta[1,2-d]pyrimidin-4-yl)amidines with hydroxylamine hydrochloride through a subsequent rearrangement reaction. Effects of the products as well as the structurally related N-[4-([1,2,4]oxadiazol-5-yl)-2,3-dihydro[1]benzoxepin-5-yl]formamide oximes and N-[4-([1,2,4]oxadiazol-5-yl)-2,3-dihydro[1]benzothiepin-5-yl]formamide oximes on platelet aggregation were evaluated.

DOI： 10.1002/jhet.1628

POLYCYCLIC N-HETEROCYCLIC COMPOUNDS, PART 77: SYNTHESIS OF [1]BENZOTHIENO[3 ',2 ':2,3]OXEPINO[4,5-d]PYRIMIDINES AND EVALUATION OF THEIR ANTIPLATELET AGGREGATION ACTIVITY

Kensuke Okuda, Takashi Nikaido, Takashi Hirota, Kenji Sasaki

SYNTHETIC COMMUNICATIONS 43 ( 12 ) 1619 - 1625 2013年6月

記述言語：英語出版者・発行元：TAYLOR & FRANCIS INC

Reaction of 3-(3-cyanopropoxy)[1]benzothiophene-2-carbonitrile with sodium hydride gave 5-amino-1,2-dihydro[1]benzothieno[3,2-d]furo[2,3-b]pyridine and 5-amino-2,3-dihydro[1]benzothieno[3,2-b]oxepin-4-carbonitrile. The latter compound served as a convenient scaffold for the synthesis of the new heterocycles [1]benzothieno[3,2:2,3]oxepino[4,5-d]pyrimidines and the parent 1,2,4,5-tetrahydro[1]benzothieno[2,3:6,7]oxepino[4,5-e]imidazo[1,2-c]pyrimidine heterocyclic system. The new compounds described in this report were evaluated as inhibitors of platelet aggregation in vitro.

DOI： 10.1080/00397911.2012.656295

Polycyclic N-Heterocyclic Compounds 73: Synthesis and Evaluation of 5-Substituted 1,2-Dihydrofuro[2,3-c]isoquinolines as Inducers of Lipoprotein Lipase mRNA Expression

Kensuke Okuda, Masahiko Yoshida, Takashi Hirota, Kenji Sasaki

JOURNAL OF HETEROCYCLIC CHEMISTRY 50 ( 51 ) E9 - E11 2013年2月

記述言語：英語出版者・発行元：WILEY-BLACKWELL

Several 5-substituted 1,2-dihydro[2,3-c]isoquinoline derivatives were synthesized as part of our research to develop new diabetes drugs. Amines and sulfanyls were used as substituents at the 5th-position. Evaluation of the effects of the newly synthesized compounds on lipoprotein lipase mRNA expression in 3T3-L1 preadipocytes revealed one promising candidate with potency comparable to that of troglitazone.

DOI： 10.1002/jhet.1016

Novel quercetin glycosides as potent anti-mrsa and anti-vre agents

Abugafar M.L. Hossion, Kenji Sasaki

Recent Patents on Anti-Infective Drug Discovery 8 ( 3 ) 198 - 205 2013年

記述言語：英語出版者・発行元：Bentham Science Publishers B.V.

Each year in the United States, at least 2 million people become infected with bacteria that are resistant to antibiotics and at least 23,000 people die each year as a direct result of these infections (Threat report 2013). Vancomycin is an FDA approved antibiotic and is growing importance in the treatment of hospital infections, with particular emphasis on its value to fight against methicillin-resistant Staphylococcus aureus (MRSA). The increasing use of vancomycin to treat infections caused by the Gram-positive MRSA in the 1970s selected for drug-resistant enterococci, less potent than staphylococci but opportunistic in the space vacated by other bacteria and in patients with compromised immune systems. The dramatic rise of antibiotic-resistant bacteria over the past two decades has stressed the need for completely novel classes of antibacterial agents. This paper reports the recent patent review on the strategy for finding novel quercetinglycoside type antibacterial agents against vancomycin-resistant bacterial strains. © 2013 Bentham Science Publishers.

DOI： 10.2174/1574891X08666131210124649

Quinolone Analogues 12: Synthesis and Tautomers of 2-Substituted 4-Quinolones and Related Compounds

Yoshihisa Kurasawa, Kiminari Yoshida, Naoki Yamazaki, Kotoji Iwamoto, Yoshihiko Hamamoto, Eisuke Kaji, Kenji Sasaki, Yoshito Zamami

JOURNAL OF HETEROCYCLIC CHEMISTRY 49 ( 6 ) 1323 - 1331 2012年11月

記述言語：英語出版者・発行元：WILEY-BLACKWELL

The 4-quinolone-2-carboxylates 4a,b were converted into the 4-quinolone-2-carbohydrazides 5a,b, hydrazones 6,7,10, and related compounds 8,9,11. The 4-methoxyquinoline-2-carboxylate 12 was also transformed into the 4-methoxyquinoline-2-carbohydrazide 13, which was modified to the hydrazone 14 and related compound 15. The antimicrobial activities of compounds 6b and 14 are described together with the 4-oxo and 4-hydroxy tautomers of compounds 4-11 in deuteriodimethyl sulfoxide and deuteriotrifluoroacetic acid.

DOI： 10.1002/jhet.922

Polycyclic N-Heterocyclic Compounds, Part 71: Synthesis and Bronchodilator Evaluation of 5-Substituted 1,2-Dihydrofuro[3,2-f][1,7]naphthyridines and Related Compounds

Kensuke Okuda, Tetsuo Matsushita, Takashi Hirota, Kenji Sasaki

JOURNAL OF HETEROCYCLIC CHEMISTRY 49 ( 4 ) 742 - 747 2012年7月

記述言語：英語出版者・発行元：WILEY-BLACKWELL

Several 5-substituted 1,2-dihydrofuro[3,2-f][1,7]naphthyridines were synthesized as part of our research to develop new effective bronchodilators. Amines, sulfanyls, and alcohols were used as substituents at the fifth position. Tetracyclic compounds were also obtained. Evaluation of the effects of the newly synthesized compounds on carbamoylcholine chloride-induced contractions of trachea revealed one promising bronchodilator candidate with potency comparable to that of 3-isobutyl-1-methylxanthine.

DOI： 10.1002/jhet.846

Synthesis and antimalarial activity of calothrixins A and B, and their N-alkyl derivatives

Kohji Matsumoto, Tominari Choshi, Mai Hourai, Yoshito Zamami, Kenji Sasaki, Takumi Abe, Minoru Ishikura, Noriyuki Hatae, Tatsunori Iwamura, Shigeo Tohyama, Junko Nobuhiro, Satoshi Hibino

BIOORGANIC & MEDICINAL CHEMISTRY LETTERS 22 ( 14 ) 4762 - 4764 2012年7月

記述言語：英語出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD

We synthesized calothrixin B using our developed biomimetic method and derived N-alkyl-calothrixins A and B. The in vitro antimalarial activity of the calothrixin derivatives, including calothrixins A and B, against the Plasmodium falciparum FCR-3 strain was evaluated. All test compounds exhibited antimalarial activity over a concentration range of 6.4 x 10(-6)-1.2 x 10(-7) M. (C) 2012 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.bmcl.2012.05.064

Polycyclic N-Heterocyclic Compounds, Part 69: Synthesis of 5-amino-1,2-dihydro[1]benzofuro[3,2-d]furo[2,3-b]pyridines and their transformations to related compounds

Kensuke Okuda, Jun-ichi Takano, Takashi Hirota, Kenji Sasaki

JOURNAL OF HETEROCYCLIC CHEMISTRY 49 ( 2 ) 281 - 287 2012年3月

記述言語：英語出版者・発行元：WILEY-BLACKWELL

Reaction of 3-(3-cyanopropoxy)[1]benzofuran-2-carbonitriles with potassium tert-butoxide gave 5-amino-1,2-dihydro[1]benzofuro[3,2-d]furo[2,3-b]pyridines and 5-amino-2,3-dihydro[1]benzofuro[3,2-b]oxepin-4-carbonitriles as new ring systems. Reactions of the 5-chloro derivative, obtained from 5-amino-1,2-dihydro[1]benzofuro[3,2-d]furo[2,3-b]pyridine, produced a dihydrofuran ring-opened compound and 5-substituted compounds. J. Heterocyclic Chem.,(2011).

DOI： 10.1002/jhet.772

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