Synthesis of Substituted Piperidines, Indolizidines, Quinolizidines, and Pyrrolizidines via a Cycloaddition Strategy Using Acetylenic Sulfones as Alkene Dipole Equivalents
摘要:
The conjugate additions of beta- and gamma-chloroamines to acetylenic sulfones afford enamine sulfones, which then undergo intramolecular alkylation to produce the corresponding cyclic enamines, This provides a convenient route to substituted piperidines, indolizidines, quinolizidines, and pyrrolizidines. The enantioselective total synthesis of the alkaloid (-)-indolizidine 167B (also named gephyrotoxin 167B) was thus achieved by the cycloaddition of (S)-2-(2-chloroethyl)pyrrolidine to 1-(p-toluenesulfonyl)-1-pentyne, followed by stereoselective reduction of the enamine moiety and reductive desulfonylation.
Copper-Catalyzed Diamination of Unactivated Alkenes With Electron-Rich Amino Sources
作者:Yang Li、Arshad Ali、Junchao Dong、Yu Zhang、Lili Shi、Qun Liu、Junkai Fu
DOI:10.1021/acs.orglett.1c01313
日期:2021.5.21
The catalytic intermoleculardiamination of unactivated alkenes with electron-rich amino sources is a challenge. Herein, by employing a directing-group strategy, a copper-catalyzeddiamination of unactivated alkenes was realized. Symmetrical diamines were efficiently produced in a highly diastereoselective manner with readily available dialkylamines as amino sources, while a one-pot and two-step operation
A Convenient New Route to Piperidines, Pyrrolizidines, Indolizidines, and Quinolizidines by Cyclization of Acetylenic Sulfones with β- and γ-Chloroamines. Enantioselective Total Synthesis of Indolizidines <b>(</b><b>−</b><b>)-167B</b>, <b>(</b><b>−</b><b>)-209D</b>, <b>(</b><b>−</b><b>)-209B</b>, and <b>(</b><b>−</b><b>)-207A</b>
作者:Thomas G. Back、Katsumasa Nakajima
DOI:10.1021/jo000080p
日期:2000.7.1
the corresponding 2- or 2,6-disubstituted piperidines, while 2-(chloromethyl)pyrrolidines, 2-(2-chloroethyl)pyrrolidines, 2-(chloromethyl)piperidines, and 2-(2-chloroethyl)piperidines produced the corresponding 3-substituted pyrrolizidines, 5- or 3-substituted indolizidines, and 4-substituted quinolizidines, respectively. 8-Methyl-5-substituted indolizidines were also prepared from the appropriate methyl-substituted
作者:Geert Hooyberghs、Sofie Van Hove、Jeroen Jacobs、Luc Van Meervelt、Erik V. Van der Eycken
DOI:10.1002/ejoc.201500402
日期:2015.7
A one-pot sequential A3-coupling-azidation-cyclisation approach leading to potentially biologically active diazepine analogues has been developed. The implementation of the A3-coupling reaction ensures diversity. Attention is given to this so far rarely studied structural motif of fused heterocyclic diazepines.
The present invention relates to compositions and methods using for activating Peroxisomal Proliferator Activating Receptor (PPAR)-β/δ and/or PPAR-γ. In some embodiments, the present invention relates to compounds and methods of treating a disease or disorder associated with PPAR-β/δ and/or PPAR-γ. In some embodiments, present invention relates to compounds and methods of treating Alzheimer's disease, diabetes, and reduced cognition.
Two in one: Two pseudorotaxanes can be combined to form a twin‐axial hetero[7]rotaxane (see picture) by using the copper‐catalyzed alkyne–azide “click” reaction. The synthetic route, in which twin‐axial and single‐axial rotaxanes are formed, combines self‐assembly and the formation of covalent bonds to ensure the correct positioning of the two types of rings in the final product.