Chemotaxonomic significance of lignans from the root bark of Lycium chinense Miller

Nine lignans were isolated from the 75% ethanol extract of the dried root bark of Lycium chinense Miller. Among them, (−)- and (+)-lycinseol A ( 1a and 1b ) represent a pair of new nor-lignans, while curlignan ( 2 ), nectandrin B ( 3 ), odoratisol C ( 4 ), (−)-licarin A ( 5 ), 5′-demethoxydaphneticin ( 6 ), meso-dihydroguaiaretic acid ( 7 ) and macelignan ( 8 ) were isolated from the genus Lycium for the first time. Their structures including absolute configurations were comprehensively elucidated using HR-MS, NMR, ECD and computational chemistry. Furthermore, the chemotaxonomic significance of these lignans were elaborated upon.