Antimalarial Activity of Natural and Synthetic Prodiginines
作者:Kancharla Papireddy、Martin Smilkstein、Jane Xu Kelly、Shweta、Shaimaa M. Salem、Mamoun Alhamadsheh、Stuart W. Haynes、Gregory L. Challis、Kevin A. Reynolds
DOI:10.1021/jm200543y
日期:2011.8.11
Prodiginines are a family of linear and cyclic oligopyrrole red-pigmented compounds. Herein we describe the in vitro antimalarial activity of four natural (IC50 = 1.7–8.0 nM) and three sets of synthetic prodiginines against Plasmodium falciparum. Set 1 compounds replaced the terminal nonalkylated pyrrole ring of natural prodiginines and had diminished activity (IC50 > 2920 nM). Set 2 and set 3 prodiginines
Hypervalent iodine(III): selective and efficient single-electron-transfer (SET) oxidizing agent
作者:Toshifumi Dohi、Motoki Ito、Nobutaka Yamaoka、Koji Morimoto、Hiromichi Fujioka、Yasuyuki Kita
DOI:10.1016/j.tet.2009.10.040
日期:2009.12
ethers, affording the corresponding aromatic cation radicals. Since then, hypervalent iodine(III) has been utilized as a selective and efficient SET oxidizingagent that enables a variety of direct C–H functionalizations of aromatic rings in electron-rich arenes under mild conditions. We have now extended the original method to work in a series of heteroaromatic compounds such as thiophenes, pyrroles,
Direct Synthesis of Bipyrroles Using Phenyliodine Bis(trifluoroacetate) with Bromotrimethylsilane
作者:Toshifumi Dohi、Koji Morimoto、Akinobu Maruyama、Yasuyuki Kita
DOI:10.1021/ol060333m
日期:2006.5.1
[reaction: see text] The hypervalent iodine(III) reagent, phenyliodinebis(trifluoroacetate) (PIFA), mediates the unprecedented, oxidative coupling reaction of pyrroles to give alpha-linked bipyrroles selectively in the presence of bromotrimethylsilane. This straightforward synthesis could provide 2,3'-bipyrrole by the choice of a N-substituent of pyrrole. Mechanistic consideration of the present reaction
Regioselective Bipyrrole Coupling of Pyrroles and 3-Substituted Pyrroles Using Phenyliodine(III) Bis(trifluoroacetate)
作者:Yasuyuki Kita、Toshifumi Dohi、Koji Morimoto、Motoki Ito
DOI:10.1055/s-2007-983798
日期:2007.9
A series of electron-rich bipyrroles were prepared by the regioselective, phenyliodine(III) bis(trifluoroacetate) (PIFA) induced oxidative coupling of pyrroles in the presence of bromotrimethylsilane. Using pyrrole and 3,4-disubstituted pyrroles gave exclusively 2,2′-linked bipyrroles without the formation of other bipyrrole regioisomers. The 3-alkyl- or 3-aryl-substituted pyrroles gave unsymmetrical
Direct Cyanation of Heteroaromatic Compounds Mediated by Hypervalent Iodine(III) Reagents: In Situ Generation of PhI(III)−CN Species and Their Cyano Transfer
作者:Toshifumi Dohi、Koji Morimoto、Naoko Takenaga、Akihiro Goto、Akinobu Maruyama、Yorito Kiyono、Hirofumi Tohma、Yasuyuki Kita
DOI:10.1021/jo061820i
日期:2007.1.1
in our laboratory provided insights into the real active iodine(III) species during the reaction; the reaction is induced by an active hypervalent iodine(III) species having a cyano ligand in situ generated by ligand exchange reaction at the iodine(III) center between trifluoroacetoxy group in PIFA and TMSCN, and effective cyanide introduction into heteroaromatic compounds is achieved by means of the