Two New Phenolic Glycosides from the Aerial Part of Dryopteris erythrosora

BACKGROUND: Dryopteris erythrosora (D.C. Eaton) Kuntze is a species of fern in the family of Dryopteridaceae, which is distributed throughout East Asia. The genus Dryopteris has been used as traditional medicine, especially to treat hepatitis and protect liver. However, only few studies of chemical constituents of D. erythrosora have been conducted so far. OBJECTIVE: In this study, we investigated the phytochemical constituents of D. erythrosora. MATERIALS AND METHODS: The 80% methanol extract of the aerial part of D. erythrosora was used for the isolation of phenolic compounds. The isolated compounds were elucidated by various spectroscopic methods including nuclear magnetic resonance and mass spectrometry. RESULTS: The present phytochemical investigation on the aerial part of D. erythrosora led to the isolation of two new phenolic glycosides, 1 and 2, as well as nine known flavonoids including two flavones (3 and 4) and seven flavonols (5-11). CONCLUSION: In this study, two new phenolic glycosides together with nine known flavonoids were isolated from the aerial part of D. erythrosora. Among them, compounds 4, 8, and 11 were isolated for the first time in Dryopteridaceae family from the present investigation. These results helped us to enrich our understanding of the chemical constituents of D. erythrosora and to identify compounds 1 and 2 which could be potential chemotaxonomic markers for the species. SUMMARY: The genus Dryopteris has been used as traditional medicine, especially to treat hepatitis and protect liver. Two new phenolic glycosides were isolated from D. erythrosora. Nine known flavonoids (3-11) were isolated from D. erythrosora. Compounds 4, 8, and 11 were isolated for the first time in Dryopteridaceae family. [Image: see text] Abbreviations used: HPLC: High-performance liquid chromatography; Q-TOF LC/MS: Quadrupole-time-of-flight liquid chromatography/mass spectrometry; NMR: Nuclear magnetic resonance; TMS: Tetramethylsilane