70665-05-3Relevant articles and documents
Rapid Synthesis of α-Chiral Piperidines via a Highly Diastereoselective Continuous Flow Protocol
Shan, Chao,Xu, Jinping,Cao, Liming,Liang, Chaoming,Cheng, Ruihua,Yao, Xiantong,Sun, Maolin,Ye, Jinxing
, p. 3205 - 3210 (2022/05/07)
A practical continuous flow protocol has been developed using readily accessible N-(tert-butylsulfinyl)-bromoimine and Grignard reagents, providing various functionalized piperidines (34 examples) in superior results (typically >80% yield and with >90:10 dr) within minutes. The high-performance scale-up is smoothly carried out, and efficient synthesis of the drug precursor further showcases its utility. This flow process offers rapid and scalable access to enantioenriched α-substituted piperidines.
Chemoenzymatic Synthesis of Substituted Azepanes by Sequential Biocatalytic Reduction and Organolithium-Mediated Rearrangement
Zawodny, Wojciech,Montgomery, Sarah L.,Marshall, James R.,Finnigan, James D.,Turner, Nicholas J.,Clayden, Jonathan
supporting information, p. 17872 - 17877 (2019/01/04)
Enantioenriched 2-aryl azepanes and 2-arylbenzazepines were generated biocatalytically by asymmetric reductive amination using imine reductases or by deracemization using monoamine oxidases. The amines were converted to the corresponding N′-aryl ureas, which rearranged on treatment with base with stereospecific transfer of the aryl substituent to the 2-position of the heterocycle via a configurationally stable benzyllithium intermediate. The products are previously inaccessible enantioenriched 2,2-disubstituted azepanes and benzazepines.
Simultaneous engineering of an enzyme's entrance tunnel and active site: The case of monoamine oxidase MAO-N
Li, Guangyue,Yao, Peiyuan,Gong, Rui,Li, Jinlong,Liu, Pi,Lonsdale, Richard,Wu, Qiaqing,Lin, Jianping,Zhu, Dunming,Reetz, Manfred T.
, p. 4093 - 4099 (2017/07/10)
A new directed evolution approach is presented to enhance the activity of an enzyme and to manipulate stereoselectivity by focusing iterative saturation mutagenesis (ISM) simultaneously on residues lining the entrance tunnel and the binding pocket. This combined mutagenesis strategy was applied successfully to the monoamine oxidase from Aspergillus Niger (MAO-N) in the reaction of sterically demanding substrates which are of interest in the synthesis of chiral pharmaceuticals based on the benzo-piperidine scaffold. Reversal of enantioselectivity of Turner-type deracemization was achieved in the synthesis of (S)-1,2,3,4-tetrahydro-1-methyl-isoquinoline, (S)-1,2,3,4-tetrahydro-1-ethylisoquinoline and (S)-1,2,3,4-tetrahydro-1-isopropylisoquinoline. Extensive molecular dynamics simulations indicate that the altered catalytic profile is due to increased hydrophobicity of the entrance tunnel acting in concert with the altered shape of the binding pocket.
