Zobrazeno 1 - 10
of 22
pro vyhledávání: '"Shigeto Negi"'
Publikováno v:
Tetrahedron. 57:2701-2710
The modification of sodium bis(2-methoxyethoxy)aluminum hydride (SMEAH) with pyrrolidine provided a highly selective reducing agent to transform N -benzyl-4-ethoxycarbonylpiperidine into N -benzyl-4-formylpiperidine 1 under mild conditions. However,
Autor:
Toshikazu Shimizu, Naoyuki Shimomura, Katsuya Tagami, Hiroshi Akamatsu, Kozo Akasaka, Shigeto Negi, Yuki Komatsu, Yuichi Kimoto
Publikováno v:
Chemical and Pharmaceutical Bulletin. 47:1525-1531
Diastereoselective methylation of the enolate generated from various protected 6-oxopipecolic acid esters (3aa-3cd) was studied. The protecting groups on the carboxylic acid and amino groups significantly influenced the trans/cis selectivity in the m
Autor:
Kenji Hayashi, Kozo Akasaka, Hiroshi Naka, Yuki Komatsu, Naoyuki Shimomura, Toshikazu Shimizu, Katsuya Tagami, Shigeto Negi
Publikováno v:
Chemical and Pharmaceutical Bulletin. 47:1532-1537
An efficient synthetic process for the key intermediate of a new peptidomimetic dual metalloprotease inhibitor, ER-40133, was developed. (5R)-Methyl-6-oxopipecolic acid ester (3a), prepared from L-α-aminoadipic acid, was chemoselectively reduced to
Publikováno v:
Synthetic Communications. 27:3547-3557
Trisubstituted oxirane 1 was regiospecifically opened with LiCN in situ prepared from acetone cyanohydrin and LiH to provide the corresponding β-hydroxy nitrile 2 in satisfactory yield, enabling us to manufacture a key intermediate for a new antifun
Publikováno v:
Synthesis. 1996:991-996
Publikováno v:
Journal of Labelled Compounds and Radiopharmaceuticals. 38:1-11
The new broad-spectrum oral antibacterial agent E1101, has been labelled in the C-2 position of the aminothiazole ring using [ 14 C]thiourea. The cephalosporin analog was synthesized in 5 steps and is suitable for metabolism and disposition studies.
Autor:
Atsushi Kamada, Akihiko Tsuruoka, Shigeto Negi, Yuki Komatsu, Motosuke Yamanaka, Itaru Tsukada, Yoshimasa Machida
Publikováno v:
Chemical and Pharmaceutical Bulletin. 43:1031-1034
E1101, a new oral cephalosporin, has a (N,N-dimethylcarbamoyloxy)methyl group at the C-3 position of the cephem nucleus. The previous methods for manufacturing 3-(N,N-disubstituted carbamoyloxy)methyl cephems generate various amounts of intractable
Publikováno v:
Chemical and Pharmaceutical Bulletin. 43:1866-1871
The instability of Δ2 cephem prodrug-type ester (5a) under acidic conditions prompted us to investigate the comparative stability of Δ3 and Δ2 cephems at various pHs. The Δ2 cephem ester 5a was found to show marked instability under neutral (pH 7
Autor:
Akihiko Tsuruoka, Itaru Tsukada, Yoshimasa Machida, Atsushi Kamada, Yuuki Komatsu, Shigeto Negi, Motosuke Yamanaka
Publikováno v:
ChemInform. 26
Autor:
Atsushi Kamada, Ryoichi Hiruma, Motosuke Yamanaka, Masanobu Sasho, Isao Sugiyama, Akihiko Tsuruoka, Shigeto Negi, Itaru Tsukada, Kanemasa Katsu, Yuuki Komatsu, Yoshimasa Machida
Publikováno v:
ChemInform. 26