Zobrazeno 1 - 10
of 40
pro vyhledávání: '"Michio Tokiwa"'
Autor:
Ummareddy Venkata Subba Reddy, Bheemreddy Anusha, Zubeda Begum, Chigusa Seki, Yuko Okuyama, Michio Tokiwa, Suguru Tokiwa, Mitsuhiro Takeshita, Hiroto Nakano
Publikováno v:
Catalysts, Vol 12, Iss 12, p 1674 (2022)
Chiral primary α-amino amides, consisting of an adjacent enamine bonding site (Bronsted base site), a hydrogen bonding site (Bronsted acid site), and flexible bulky substituent groups to modify the steric factor, are proving to be extremely valuable
Externí odkaz:
https://doaj.org/article/f38abfafd05743f2b5a5a296ed82aeff
Autor:
Madhu Chennapuram, Isiaka Alade Owolabi, Chigusa Seki, Yuko Okuyama, Eunsang Kwon, Koji Uwai, Michio Tokiwa, Mitsuhiro Takeshita, Hiroto Nakano
Publikováno v:
ACS Omega, Vol 3, Iss 9, Pp 11718-11726 (2018)
Externí odkaz:
https://doaj.org/article/da7e2cff96bb44558dcff7976a934687
Autor:
Junichi Akiyama, Shigeaki Kato, Masaharu Tsubokura, Jinichi Mori, Tetsuya Tanimoto, Koichiro Abe, Shuji Sakai, Ryugo Hayano, Michio Tokiwa, Hiroaki Shimmura
Publikováno v:
PLoS ONE, Vol 10, Iss 10, p e0140482 (2015)
Following the Fukushima nuclear power plant disaster, assessment of internal radiation exposure was indispensable to predict radiation-related health threats to residents of neighboring areas. Although many evaluations of internal radiation in reside
Externí odkaz:
https://doaj.org/article/83b4b249933d4da0b30324ed936a5861
Autor:
Miku Nomura, Zubeda Begum, Chigusa Seki, Yuko Okuyama, Eunsang Kwon, Koji Uwai, Michio Tokiwa, Suguru Tokiwa, Mitsuhiro Takeshita, Hiroto Nakano
Publikováno v:
RSC Advances. 13:3715-3722
Catalytic functionality of new optically active thiourea fused γ-amino alcohols was examined in the asymmetric Mannich reaction of β-keto active methylene compounds with imines to afford chiral Mannich products, β-amino keto compounds..
Autor:
Zubeda Begum, Chigusa Seki, Yuko Okuyama, Eunsang Kwon, Koji Uwai, Michio Tokiwa, Suguru Tokiwa, Mitsuhiro Takeshita, Hiroto Nakano
Publikováno v:
RSC Advances. 13:888-894
Distinct types of new boron fused primary amino amide organocatalysts were designed and synthesized from commercially available amino acids.
Autor:
Koji Uwai, Zubeda Begum, Eunsang Kwon, Mitsuhiro Takeshita, Chigusa Seki, Divakar Ganesan, Michio Tokiwa, Suguru Tokiwa, Perumalsamy Parasuraman, Yuko Okuyama, Hiroto Nakano
Publikováno v:
Chirality. 33:454-464
New two catalysts component system comprising of a primary β-amino silyl ethers as an organocatalyst and N-protected amino acids as a co-catalyst put together worked as an efficient organocatalyst system in the hetero Diels-Alder reaction of isatins
Autor:
Rajkumar Thiyagarajan, Zubeda Begum, Chigusa Seki, Yuko Okuyama, Eunsang Kwon, Koji Uwai, Michio Tokiwa, Suguru Tokiwa, Mitsuhiro Takeshita, Hiroto Nakano
Publikováno v:
RSC Advances. 11:38925-38932
New small γ-turn type N-primary amino terminal tripeptides were applied for the asymmetric aldol reaction of ketones with aldehydes under neat conditions to afford the chiral aldol products (up to 99%, up to syn : anti/13 : 87 dr, up to 99% ee).
Autor:
Koji Uwai, Yuko Okuyama, Hiroto Nakano, Chigusa Seki, Mitsuhiro Takeshita, Michio Tokiwa, Eunsang Kwon, Zubeda Begum, Madhu Chennapuram, Perumalsamy Parasuraman, Suguru Tokiwa
Publikováno v:
RSC Advances. 10:17486-17491
A simple two catalyst component system consisting of primary β-amino alcohols as a catalyst and amino acids as a co-catalyst put together works as an efficient organocatalyst system in the hetero Diels-Alder reaction of isatins with enones to afford
Autor:
Michio Tokiwa, Mitsuhiro Takeshita, Yuko Okuyama, Hiroto Nakano, Rei Togashi, Chigusa Seki, Madhu Chennapuram, Eunsang Kwon, Koji Uwai
Publikováno v:
European Journal of Organic Chemistry. 2019:3882-3889
Autor:
Isiaka Alade Owolabi, Eunsang Kwon, Koji Uwai, Chigusa Seki, Madhu Chennapuram, Mitsuhiro Takeshita, Michio Tokiwa, Yuko Okuyama, Hiroto Nakano
Publikováno v:
Bulletin of the Chemical Society of Japan. 92(3):696-701
Asymmetric Michael addition of β-keto esters with trans-β-nitroolefins using chiral amino amide organocatalyst was tried and afforded synthetically useful chiral Michael adducts in both excellent chemical yields (up to 99%) and stereoselectivities