Alkaloids and phenolic constituents from Glaucium corniculatum

Abstract

The aerial parts of Glaucium corniculatum were phytochemically investigated. Consequently, 14 compounds, including six alkaloids (1–6) namely dehydroberberine (1), berberine (2), protpine (3), allocryptopine (4), (+)-corydine (5) and glaucine (6); six flavonoids (7–12) including quercetin (7), isorhamnetin (8), rutin (9), isorhamnetin 3-O-rutinoside (narcissoside, narcissin) (10), quercetin-3-O-glucoside-7-O-rutinoside (11), and isorhamnetin 3-O-glucoside-7-O-rutinoside (12); and hydroxycinnamic acid malate esters, (+)-phaselic acid ((+)-2-O-caffeoyl-L-malate) (13), and (+)-2-O-feruloyl-L-malate (14) were identified. Notably, the protoberberine-type isoquinoline alkaloid dehydroberberine (1) was naturally isolated for the first time, and the two flavonoids triosides (11 and 12) were identified for the first time from genus Glaucium and family Papaveraceae. Their structures were assigned through 1D, 2D NMR, HR-ESI-MS experiments, and by comparing the obtained data with those reported in the literature. The identified metabolites in G. corniculatum have important chemotaxonomic implications, suggesting that the biosynthesis of isoquinoline alkaloids is influenced by the plant's geographical location and could serve as valuable chemotaxonomic markers for identifying the plant sources. Furthermore, flavonoids and phenolic acids can be utilized to differentiate between subfamilies within the family Papaveraceae or to distinguish it from closely related families.