Results 341 to 350 of about 70,546 (390)

Diastereo‐ and Enantioselective Synthesis of Spiro‐Pyrrolidine‐Pyr­azolones by Squaramide‐Catalyzed Cascade Aza‐Michael/Michael Reactions

, 2016
A new method was developed to rapidly generate a series of spiro-pyrrolidine-pyrazolones by using a squaramide-catalyzed cascade aza-Michael/Michael addition of either tosylaminomethyl enones or enoates to unsaturated pyrazolones.
Jun-hua Li, Hongliang Wen, Lei Liu, D. Du   +3 more
semanticscholar   +1 more source

Discovery of Pyrrolidine-Containing GPR40 Agonists: Stereochemistry Effects a Change in Binding Mode.

Journal of Medicinal Chemistry, 2017
A novel series of pyrrolidine-containing GPR40 agonists is described as a potential treatment for type 2 diabetes. The initial pyrrolidine hit was modified by moving the position of the carboxylic acid, a key pharmacophore for GPR40.
Elizabeth A. Jurica, Ximao Wu, Kristin N Williams, Andrés S. Hernández, David S. Nirschl, R. Rampulla, A. Mathur, Min Zhou, Gary G Cao, Chunshan Xie, Biji Jacob, Hong Cai, Tao Wang, B. Murphy, Heng Liu, Carrie Xu, L. Kunselman, M. Hicks, Qin Sun, D. Schnur, Doree Sitkoff, E. Dierks, Atsu Apedo, D. Moore, Kimberly A. Foster, M. Cvijic, Reshma Panemangalore, Neil Flynn, B. Maxwell, Yang Hong, Yuan Tian, J. Wilkes, B. Zinker, J. Whaley, J. Barrish, J. Robl, W. R. Ewing, B. Ellsworth   +37 more
semanticscholar   +1 more source

Pyrrolidine analogues of nucleosides and nucleotides

Nucleic Acids Symposium Series, 2008
Among the structurally diverse nucleoside phosphonic acids, several compounds possessing strong antiviral properties have been found. Our effort in this area was focused to the synthesis of novel compounds - pyrrolidine-based nucleoside phosphonic acids and their derivatives.
Libor Krásný, Ivan Rosenberg, Hana Šanderová, Soňa Kovačková, Petr Kočalka, Dominik Rejman, Radek Pohl, Alžběta Švenková   +7 more
openaire   +3 more sources

Asymmetric Synthesis of 2′‐Trifluoromethylated Spiro‐pyrrolidine‐3,3′‐oxindoles via Squaramide‐Catalyzed Umpolung and 1,3‐Dipolar Cycloaddition

, 2016
The introduction of a trifluoromethyl group into the 2-position of spiro-pyrrolidine-3,3-oxindoles is described. By using 1mol% of a quinine-derived squaramide as catalyst, the 2,2,2-trfluoroethylamine (CF3CH2NH2)-derived ketimine is transformed ...
Jinhuan Su, Zelin Ma, Xiaoyuan Li, Li Lin, Zhiqiang Shen, Peiju Yang, Yuan Li, Hailin Wang, Wenjin Yan, Kairong Wang, Rui Wang   +10 more
semanticscholar   +1 more source

Molecular Iodine-Mediated α-C-H Oxidation of Pyrrolidines to N,O-Acetals: Synthesis of (±)-Preussin by Late-Stage 2,5-Difunctionalizations of Pyrrolidine.

Journal of Organic Chemistry, 2017
We previously reported an iterative synthesis of unsymmetrical 2,5-disubstituted pyrrolidines from pyrrolidine by two rounds of redox-triggered α-C-H functionalization.
Hao-Jie Rong, Jun-Jun Yao, Jikun Li, J. Qu   +3 more
semanticscholar   +1 more source

Pyrrolidine modified PANF catalyst for asymmetric Michael addition of ketones to nitrostyrenes in aqueous phase

, 2016
Three chiral pyrrolidine functionalized polyacrylonitrile fiber catalysts have been designed, prepared, and evaluated for their catalytic performance in asymmetric Michael addition of ketones to nitrostyrenes in water.
Jianguo Du, B. Shuai, M. Tao, Guangwei Wang, Wenqin Zhang   +4 more
semanticscholar   +1 more source

Synthesis of 3-substituted pyrrolidines

Chemistry of Heterocyclic Compounds, 2007
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Marina A. Yurovskaya, Alexander V. Kurkin, E. A. Sumtsova   +2 more
openaire   +3 more sources

Spiro-Pyrrolidine-Catalyzed Asymmetric Conjugate Addition of Hydroxylamine to Enals and 2,4-Dienals

, 2016
A spiro-pyrrolidine-catalyzed tandem aza-1,4-addition/hemi-acetalization reaction was developed with excellent enantioselectivity (12 examples of >= 99% ee), and several substrates proceeded with higher ee (up to 10% increase) compared with the ...
Qing-Yun Dou, Y. Tu, Ye Zhang, Jin‐Miao Tian, Fu‐Min Zhang, Shao-Hua Wang   +5 more
semanticscholar   +1 more source

Pyrroles, pyrrolines and pyrrolidines

1991
Publisher Summary This chapter presents a review of pyrrole chemistry. It presents a description of the syntheses and reactions of monocyclic compounds, which includes annulation reactions, dipyrroles, dipyrrolylmethanes, pyrrole polymers. Intermediate pyrrole in synthetic routes to pyrrolizidine alkaloids and porphyrins are briefly discussed ...
Asmita V. Patel, Trevor A. Crabb
openaire   +2 more sources

Catalytic asymmetric construction of spiro[pyrrolidine-2,3'-oxindole] scaffolds through chiral phosphoric acid-catalyzed 1,3-dipolar cycloaddition involving 3-amino oxindoles.

Chemical Communications, 2015
The catalytic asymmetric three-component 1,3-dipolar cycloaddition of 3-amino oxindoles with aldehydes and nitroolefins under the catalysis of a chiral phosphoric acid is reported.
Guodong Zhu, Baomin Wang, Xiaoze Bao, Huanrui Zhang, Qian Wei, Jingping Qu   +5 more
semanticscholar   +1 more source