- Kinetic resolution ofN-aryl β-amino alcoholsviaasymmetric aminations of anilines
-
An efficient kinetic resolution ofN-aryl β-amino alcohols has been developedviaasymmetricpara-aminations of anilines with azodicarboxylates enabled by chiral phosphoric acid catalysis. Broad substrate scope and high kinetic resolution performances were afforded with this method. Control experiments supported the critical roles of the NH and OH group in these reactions.
- Guo, Zheng,Xie, Jinglei,Hu, Tao,Chen, Yunrong,Tao, Houchao,Yang, Xiaoyu
-
supporting information
p. 9394 - 9397
(2021/09/22)
-
- Mechanochemical Synthesis of 1,2-Diketoindolizine Derivatives from Indolizines and Epoxides Using Piezoelectric Materials
-
A simple and efficient mechanochemical-induced approach for the synthesis of 1,2-diketoindolizine derivatives has been developed. BaTiO3 was used as the piezoelectric material in this transformation. This method features no usage of solvent, simple experimental operation, scalable potential, and high conversion efficiency, which make it attractive and practical.
- Wang, Yumei,Zhang, Ziwu,Deng, Lichan,Lao, Tianfeng,Su, Zhengquan,Yu, Yue,Cao, Hua
-
p. 7171 - 7176
(2021/09/14)
-
- Reprogramming Epoxide Hydrolase to Improve Enantioconvergence in Hydrolysis of Styrene Oxide Scaffolds
-
Enantioconvergent hydrolysis by epoxide hydrolase is a promising method for the synthesis of important vicinal diols. However, the poor regioselectivity of the naturally occurring enzymes results in low enantioconvergence in the enzymatic hydrolysis of styrene oxides. Herein, modulated residue No. 263 was redesigned based on structural information and a smart variant library was constructed by site-directed modification using an “optimized amino acid alphabet” to improve the regioselectivity of epoxide hydrolase from Vigna radiata (VrEH2). The regioselectivity coefficient (r) of variant M263Q for the R-isomer of meta-substituted styrene oxides was improved 40–63-fold, and variant M263V also exhibited higher regioselectivity towards the R-isomer of para-substituted styrene oxides compared with the wild type, which resulted in improved enantioconvergence in hydrolysis of styrene oxide scaffolds. Structural insight showed the crucial role of residue No. 263 in modulating the substrate binding conformation by altering the binding surroundings. Furthermore, increased differences in the attacking distance between nucleophilic residue Asp101 and the two carbon atoms of the epoxide ring provided evidence for improved regioselectivity. Several high-value vicinal diols were readily synthesized (>88% yield, 90%–98% ee) by enantioconvergent hydrolysis using the reprogrammed variants. These findings provide a successful strategy for enhancing the enantioconvergence of native epoxide hydrolases through key single-site mutation and more powerful enzyme tools for the enantioconvergent hydrolysis of styrene oxide scaffolds into single (R)-enantiomers of chiral vicinal diols. (Figure presented.).
- Li, Fu-Long,Qiu, Yan-Yan,Zheng, Yu-Cong,Chen, Fei-Fei,Kong, Xu–Dong,Xu, Jian-He,Yu, Hui-Lei
-
supporting information
p. 4699 - 4706
(2020/09/21)
-
- Regio- and chemoselective rearrangement of terminal epoxides into methyl alkyl and aryl ketones
-
The development of the highly active pincer-type rhodium catalyst 2 for the nucleophilic Meinwald rearrangement of functionalised terminal epoxides into methyl ketones under mild conditions is presented. An excellent regio- and chemoselectivity is obtained for the first time for aryl oxiranes.
- Tian, Yingying,Jürgens, Eva,Kunz, Doris
-
supporting information
p. 11340 - 11343
(2018/10/31)
-
- OXYSTEROLS AND METHODS OF USE THEREOF
-
Compounds are provided according to Formula (I): and pharmaceutically acceptable salts thereof, and pharmaceutical compositions thereof; wherein R2, R3, R4, R5, and and R6 are as defined herein. Compounds of the present invention are contemplated useful for the prevention and treatment of a variety of conditions.
- -
-
Paragraph 00572
(2018/05/16)
-
- Catalytic Enantioselective Conversion of Epoxides to Thiiranes
-
A highly efficient and enantioselective Br?nsted acid catalyzed conversion of epoxides to thiiranes has been developed. The reaction proceeds in a kinetic resolution, furnishing both epoxide and thiirane in high yields and enantiomeric purity. Heterodimer formation between the catalyst and sulfur donor affords an effective way to prevent catalyst decomposition and enables catalyst loadings as low as 0.01 mol %.
- Liao, Saihu,Leutzsch, Markus,Monaco, Mattia Riccardo,List, Benjamin
-
supporting information
p. 5230 - 5233
(2016/05/19)
-
- PPAR-sparing thiazolidinedione salts for the treatment of metabolic diseases
-
The present invention relates to novel salts of thiazolidinediones and other pharmaceutical agents that are useful for treating and/or preventing metabolic diseases (e.g., diabetes, or neurodegenerative diseases (e.g., Alzheimer's Disease).
- -
-
Page/Page column 106
(2015/09/28)
-
- PPAR-SPARING THIAZOLIDINEDIONES AND COMBINATIONS FOR THE TREATMENT OF NEURODEGENERATIVE DISEASES
-
The present invention relates to PPARy- sparing compounds and pharmaceutical compositions formulated with such compounds that are useful for treating, delaying the onset of, or reducing the symptoms of a neurodegenerative disorder including Huntington's disease, epilepsy, AMS, and MS.
- -
-
Paragraph 0380; 0381
(2014/07/07)
-
- THIAZOLIDINEDIONE ANALOGUES
-
The present invention relates to thiazolidinedione analogues that are useful for treating hypertension, diabetes, and inflammatory diseases. In other aspects, the present invention also presents methods of treating hypertension, diabetes, or other inflamm
- -
-
Page/Page column 60
(2010/10/03)
-
- Lithiated fluorinated styrene oxides: Configurational stability, synthetic applications, and mechanistic insight
-
The configurational stability of some lithiated fluorinated styrene oxides has been investigated. Chemical studies have shown that in ethereal solvents α-lithiated ortho-, meta-, and para-fluorostyrene oxides (2-Li, α-5-Li, and α-6-Li) are all configurationally stable in the reaction time scale, whereas a-lithiated ortho-, meta-, and paratrifluoromethylstyrene oxides (9-Li, 13-Li, and 14-Li) are configurationally unstable. Optically active oxiranyllithiums 2-Li and 9-Li, could be stereospecifically generated and quenched with electrophiles. The corresponding derivatives were then successfully subjected to regiospecific ring-opening reactions with amines to give fluorinated ssamino alcohols with a stereodefined quaternary carbinol center, which are useful synthons in medicinal chemistry. The barriers of inversion have been calculated (Eyring equation) for oxiranyllithiums 9-Li, 13-Li, and 14-Li by determining the enantiomeric ratios after electrophilic quenching on aging the enantioenriched organolithium for different times in THF; in the case of 9-Li, activation parameters have also been determined. Mechanisms that may be responsible of the racemization oxiranyllithiums 9-Li, 13-Li, and 14-Li undergo once generated are also discussed.
- Capriati, Vito,Florio, Saverio,Perna, Filippo Maria,Salomone, Antonio
-
scheme or table
p. 9778 - 9788
(2010/11/02)
-
- THIAZOLIDINEDIONE ANALOGUES FOR THE TREATMENT OF HYPERTENSION
-
The present invention relates to thiazolidinedione analogues that are useful for treating hypertension, diabetes, and inflammatory diseases. Formula (I), wherein: each of R1 and R4 is independently selected from H, halo, aliphatic, a
- -
-
Page/Page column 36
(2009/04/25)
-