Glycyrrhizic acid(GA),as a traditional herbal,can self-assemble into helical nanofiber in the water.The formed helical nanostructures can be employed as scaffolds for asymmetric Diels-Alder reaction.Through co-assembl...Glycyrrhizic acid(GA),as a traditional herbal,can self-assemble into helical nanofiber in the water.The formed helical nanostructures can be employed as scaffolds for asymmetric Diels-Alder reaction.Through co-assembling with a series of achiral copper-ligands,the chirality of GA helical nanostructures can be transferred to catalytic site,and resulted assemblies showed moderated enantioselectivity toward catalysis of Diels-Alder reaction.展开更多
Chiral heteroatom-containing bicyclic scaffolds are important pharmacophores and prevalent in bioactive natural products and drug molecules.Herein,we report a unified approach for the divergent synthesis of chiral het...Chiral heteroatom-containing bicyclic scaffolds are important pharmacophores and prevalent in bioactive natural products and drug molecules.Herein,we report a unified approach for the divergent synthesis of chiral heteroatom-containing bicyclic derivatives by lanthanide(lil)-catalyzed asymmetric inverse-electron-demand Diels-Alder reactions of 2-pyrones.These reactions occur with vari-ous readily available dihydropyrroles and dihydrofurans as dienophiles,providing a step-economical synthetic platform for densely functionalized ciss-hydroindoles and cis-hydrobenzofurans with excellent yields and enantioselectivities.The synthetic utility of this approach is demonstrated by the concise synthesis of(-)-α-lycorane and(-)-lycorine alkaloids.展开更多
Since the discovery of left-handed G-quadruplex(L-G4)structure formed by natural DNA,there has been a growing interest in its potential functions.This study utilised it to catalyse enantioselective Diels-Alder reactio...Since the discovery of left-handed G-quadruplex(L-G4)structure formed by natural DNA,there has been a growing interest in its potential functions.This study utilised it to catalyse enantioselective Diels-Alder reactions,considering its different optical rotation compared to an ordinary G4.It was determined that when L-G4 was used with a combination of copper(Ⅱ)ions,there was a good enantioselectivity(-52%ee)without further addition of ligands.When further consideration was given by adding G4 ligands,G4 was further stabilised,even obtaining a better enantioselectivity(up to-80%ee).Moreover,when using ligands that have regulatory effects on G4,the ee value can be adjusted.In this work,a minimal left-handed G4 was reported.A follow-up study was also con ducted,which recovers that the minimal left-handed G4 remains its catalytic effect and enantioselectivity,but is not so effective as the former case.This indicates that a complete G4 structure is relatively conducive to chiral catalysis.展开更多
基金the National Natural Science Foundation of China(Nos.21861132002,21773043)Chinese Academy of Sciences(Nos.XDB12020200,QYZDJ-SSW-SLH044)for the financial support
文摘Glycyrrhizic acid(GA),as a traditional herbal,can self-assemble into helical nanofiber in the water.The formed helical nanostructures can be employed as scaffolds for asymmetric Diels-Alder reaction.Through co-assembling with a series of achiral copper-ligands,the chirality of GA helical nanostructures can be transferred to catalytic site,and resulted assemblies showed moderated enantioselectivity toward catalysis of Diels-Alder reaction.
基金the National Natural Science Foundation of China(Grant No.22071030)Fudan University for financial support。
文摘Chiral heteroatom-containing bicyclic scaffolds are important pharmacophores and prevalent in bioactive natural products and drug molecules.Herein,we report a unified approach for the divergent synthesis of chiral heteroatom-containing bicyclic derivatives by lanthanide(lil)-catalyzed asymmetric inverse-electron-demand Diels-Alder reactions of 2-pyrones.These reactions occur with vari-ous readily available dihydropyrroles and dihydrofurans as dienophiles,providing a step-economical synthetic platform for densely functionalized ciss-hydroindoles and cis-hydrobenzofurans with excellent yields and enantioselectivities.The synthetic utility of this approach is demonstrated by the concise synthesis of(-)-α-lycorane and(-)-lycorine alkaloids.
基金This work was supported by the National Natural Science Foundation of China(Nos.21432008,91753201,and 21721005).
文摘Since the discovery of left-handed G-quadruplex(L-G4)structure formed by natural DNA,there has been a growing interest in its potential functions.This study utilised it to catalyse enantioselective Diels-Alder reactions,considering its different optical rotation compared to an ordinary G4.It was determined that when L-G4 was used with a combination of copper(Ⅱ)ions,there was a good enantioselectivity(-52%ee)without further addition of ligands.When further consideration was given by adding G4 ligands,G4 was further stabilised,even obtaining a better enantioselectivity(up to-80%ee).Moreover,when using ligands that have regulatory effects on G4,the ee value can be adjusted.In this work,a minimal left-handed G4 was reported.A follow-up study was also con ducted,which recovers that the minimal left-handed G4 remains its catalytic effect and enantioselectivity,but is not so effective as the former case.This indicates that a complete G4 structure is relatively conducive to chiral catalysis.
