Total synthesis of quasi-symmetric dihydrofuran lignans (−)-ribesin A and B isolated from Ribes nigrum leaves

Dihydrofuran lignans ribesin A ( 1 ) and ribesin B ( 2 ) isolated from Ribes nigrum leaves were chemically synthesized for the first time using oxa-Michael addition–carbocyclization and double-bond migration as key steps. However, the NMR data of synthesized ribesin B ( 2 ) with vanillin scaffolds were slightly inconsistent with those of reported ribesin B ( 2 ). Through further synthetic study, the structure of natural ribesin B ( 2 ) was revised to that of 3 , which has unique isovanillin scaffolds. Moreover, the asymmetric total synthesis of natural products ribesin A ( 1 ) and ribesin B ( 3 ) was achieved using chiral propargyl alcohols as the starting materials prepared via lipase-catalyzed kinetic resolution. • Dihydrofuran lignans ribesin A and B were chemically synthesized. • The structure of ribesin B was revised to an isovanillin derivative. • The asymmetric synthesis of natural (−)-ribesin A and B was achieved.