Antimalarial Pyrido[1,2-<i>a</i>]benzimidazoles: Lead Optimization, Parasite Life Cycle Stage Profile, Mechanistic Evaluation, Killing Kinetics, and in Vivo Oral Efficacy in a Mouse Model
作者:Kawaljit Singh、John Okombo、Christel Brunschwig、Ferdinand Ndubi、Linley Barnard、Chad Wilkinson、Peter M. Njogu、Mathew Njoroge、Lizahn Laing、Marta Machado、Miguel Prudêncio、Janette Reader、Mariette Botha、Sindisiwe Nondaba、Lyn-Marie Birkholtz、Sonja Lauterbach、Alisje Churchyard、Theresa L. Coetzer、Jeremy N. Burrows、Clive Yeates、Paolo Denti、Lubbe Wiesner、Timothy J. Egan、Sergio Wittlin、Kelly Chibale
DOI:10.1021/acs.jmedchem.6b01641
日期:2017.2.23
Further structure–activityrelationship (SAR) studies on the recently identified pyrido[1,2-a]benzimidazole (PBI) antimalarials have led to the identification of potent, metabolically stable compounds with improved in vivo oral efficacy in the P. berghei mouse model and additional activity against parasite liver and gametocyte stages, making them potential candidates for preclinical development. Inhibition
对最近鉴定出的吡啶并[1,2- a ]苯并咪唑(PBI)抗疟药的进一步结构-活性关系(SAR)研究已导致鉴定出有效的,代谢稳定的化合物,从而在伯氏疟原虫小鼠模型中具有改善的体内口服功效以及针对寄生虫肝脏和配子细胞阶段的额外活性,使其成为临床前开发的潜在候选者。抑制hezozoin的形成可能有助于其作用机理。
Stereoselective Reduction of α-Fluoro-β-keto Esters by NADH and NADPH-Dependent Ketoreductases
作者:Thomas K. Green、Anil Damarancha、Matthew Vanagel、Brandon Showalter、Sandra Kolberg、Alexander Thompson
DOI:10.1002/ejoc.201900644
日期:2019.7.7
Dynamicreductivekinetic resolution is applied toward the synthesis of α‐fluorinated‐β‐hydroxy esters using a set of commercially available ketoreductases. In many examples, the reactions are rapid (<1 h) and quantitative with high de and ee. 19F NMR spectroscopy proves useful for analysis of stereochemistry using in‐tube Mosher ester derivatization.
动态还原动力学拆分应用于使用一组可商购的酮还原酶合成α-氟代-β-羟基酯。在许多实例中,反应是快速的(<1小时),并且定量分析具有很高的de和ee值。19 F NMR光谱证明对使用管内Mosher酯衍生化的立体化学分析有用。
Synthesis of a Chiral Quaternary Carbon Center Bearing a Fluorine Atom: Enantio- and Diastereoselective Guanidine-Catalyzed Addition of Fluorocarbon Nucleophiles
The perfect combination: The title reaction provides adducts having quaternarycarboncentersbearing a fluorineatom with high ee and d.r. values (see scheme). The mechanism and origin of stereoselectivity were elucidated by DFT calculations. The bifunctional mode of the guanidine catalysis was demonstrated in the transition states resulting from the DFT results.
Asymmetric Mannich-type Reactions of Fluorinated Ketoesters with Binaphthyl-Modified Thiourea Catalysts
作者:Young-Ku Kang、Sung-Je Yoon、Dae-Young Kim
DOI:10.5012/bkcs.2011.32.4.1195
日期:2011.4.20
enantioselective Mannich-type reaction promoted by chiral binaphthyl-modified bifunctionalorganocatalysts is described. The treatment of α-fluoro-β-ketoesters with N-Boc imines under mild reactionconditions afforded the corresponding β-aminated α-fluoro-β-ketoesters with excellent enantioselectivities (upto 98% ee).Key Words : Mannichreaction, Asymmetric catalysis, Bifunctional organocatalyst, α-Fluoro-β-ketoesters
Asymmetric generation of fluorine-containing quaternary carbons adjacent to tertiary stereocenters: uses of fluorinated methines as nucleophiles
作者:Xiao Han、Jie Luo、Chen Liu、Yixin Lu
DOI:10.1039/b823184b
日期:——
Organocatalytic asymmetric Michael reactions of fluorinatednucleophiles with nitroolefins catalyzed by Cinchona alkaloid-derived thiourea catalysts generated the desired Michael products containing vicinal fluorinated quaternary and tertiary chiral centers with exceptional enantioselectivity.