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Yuya Nakatsuji Prof. Dr. Yusuke Kobayashi Sakyo Masuda Prof. Dr. Yoshiji Takemoto 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(8):2633-2637
Organo-radical catalysts have recently attracted great interest, and the development of this field can be expected to broaden the applications of organocatalysis. Herein, the first example of a radical-generating system is reported that does not require any photoirradiation, radical initiators, or preactivated substrates. The oxidative C−C-bond cleavage of 2-substituted cyclohexanones was achieved using an azolium salt and a hydroquinone as co-catalysts. A catalytic mechanism was proposed based on the results of diffusion-ordered spectroscopy and cyclic voltammetry measurements, as well as computational studies. 相似文献
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The synthesis of a novel class of aminoglycoside, pyranmycin, and a convenient method for the preparation of 6-amino-L-idopyranosides were reported. One of the members in the reported pyranmycin families, TC010, has prominent activity against Escherichia coli, Staphylococcus aureus, and Bacillus megaterium. We also discovered that the (4)C(1) chair conformation on ring III of pyranmycin is essential for the antibacterial activity. [reaction: see text] 相似文献
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Shinji Fushiya Yoshikazu Sato Shigeo Nozoe Kyosuke Nomoto Tsunematsu Takemoto Sei-ichi Takagi 《Tetrahedron letters》1980,21(32):3071-3072
A new amino acid derivative possessing an iron chelating activity was isolated from root washings of water cultured under iron deficient conditions. The structure of this compound, avenic acid A has been determined as 2(S),3′(S),3″(S)-N-[3-(3-hydroxy-3-carboxypropylamino)-3-carboxypropyl]-homoserine (1) on the basis of chemical and spectroscopic evidence. 相似文献
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Takemoto Y 《Organic & biomolecular chemistry》2005,3(24):4299-4306
Hydrogen-bonding interaction plays a crucial role in the molecular recognition and activation processes of various biologically important reactions that are mediated by enzymes and antibodies in living organisms. Recently, it has been shown that a hydrogen-bonding donor can be used as a general acid catalyst for various types of reactions in organic chemistry. In this article, we describe enantioselective reactions catalyzed by urea and thiourea derivatives as general acid catalysts as well as diastereoselective reactions. This perspective provides an overview of this rapidly growing field. 相似文献