Asymmetric nucleophilic addition of 3-substituted NBoc oxindoles to 3-bromooxindoles was designed to directly construct hetero-3,3′-bisoxindoles,with varying vicinal quaternary carbon stereocenters and N-substituents...Asymmetric nucleophilic addition of 3-substituted NBoc oxindoles to 3-bromooxindoles was designed to directly construct hetero-3,3′-bisoxindoles,with varying vicinal quaternary carbon stereocenters and N-substituents.The reaction progressed efficiently with high yields,good diastereo-and enantioselectivity(up to>99%ee)under mild reaction conditions catalyzed by chiral N,N′-dioxide/metal complexes.This methodology enabled the facile transformation of the generated hetero-3,3’-bisoxindoles into diverse hexahydropyrroloindole alkaloids with potential antiparasitic and anticancer properties.展开更多
In this paper,we report a full account of the synthesis of dimeric hexahydropyrroloindole alkaloids and its analogues.The key feature of our new strategy is the novel catalytic copper(10%)mediated intramolecular aryla...In this paper,we report a full account of the synthesis of dimeric hexahydropyrroloindole alkaloids and its analogues.The key feature of our new strategy is the novel catalytic copper(10%)mediated intramolecular arylations of o-haloanilides followed by intermolecular oxidative dimerization of the resulting oxindoles in one pot.This sequential reaction leads to the key intermediates for the synthesis of(+)-chimonanthine,(+)-folicanthine,(-)-calycanthine and(-)-ditryptophenaline.Graphical Abstract In the presence of catalytic amount of cuprous iodide(10%),an intramolecular arylation of ohaloanilides followed by an intermolecular oxidative dimerization of the resulting oxindoles leads to a commonintermediate for the synthesis of(+)-chimonanthine,(+)-folicanthine and(-)-calycanthine.Based on this cascade sequence,we also developed a flexible strategy towards the asymmetric syntheses of dimeric HPI alkaloids(-)-ditryptophenaline and its analogues.展开更多
基金support from the National Natural Science Foundation of China(grant nos.21625205 and U19A2014).
文摘Asymmetric nucleophilic addition of 3-substituted NBoc oxindoles to 3-bromooxindoles was designed to directly construct hetero-3,3′-bisoxindoles,with varying vicinal quaternary carbon stereocenters and N-substituents.The reaction progressed efficiently with high yields,good diastereo-and enantioselectivity(up to>99%ee)under mild reaction conditions catalyzed by chiral N,N′-dioxide/metal complexes.This methodology enabled the facile transformation of the generated hetero-3,3’-bisoxindoles into diverse hexahydropyrroloindole alkaloids with potential antiparasitic and anticancer properties.
基金This work was supported by Grants from Natural Science Foundation of China(20925205 and 21332007)the Program for Changjiang Scholars and Innovative Research Team in University(IRT13095)+1 种基金Yunnan Provincial Science and Technology Department(2010GA014)the Program for Yunling Scholars.Dr.Xiaonian Li of the Kunming Institute of Botany is gratefully acknowledged for X-ray crystallographic analysis of compound 23.CCDC 1409209(23).
文摘In this paper,we report a full account of the synthesis of dimeric hexahydropyrroloindole alkaloids and its analogues.The key feature of our new strategy is the novel catalytic copper(10%)mediated intramolecular arylations of o-haloanilides followed by intermolecular oxidative dimerization of the resulting oxindoles in one pot.This sequential reaction leads to the key intermediates for the synthesis of(+)-chimonanthine,(+)-folicanthine,(-)-calycanthine and(-)-ditryptophenaline.Graphical Abstract In the presence of catalytic amount of cuprous iodide(10%),an intramolecular arylation of ohaloanilides followed by an intermolecular oxidative dimerization of the resulting oxindoles leads to a commonintermediate for the synthesis of(+)-chimonanthine,(+)-folicanthine and(-)-calycanthine.Based on this cascade sequence,we also developed a flexible strategy towards the asymmetric syntheses of dimeric HPI alkaloids(-)-ditryptophenaline and its analogues.
