Structural Determination of A New Cycloartane Glycoside from Asplenium ruprechtii Sa. Kurata.

We characterize a new cycloartane glycoside ( 1 ), herein known as aspleniumside F, along with five known compounds as kaempferol-3- O -[(6- O -E-feruloyl)- β -D-glucopyranosyl]-(1→2)- β -D-galacopyranoside ( 2 ), quercetin- 3 - O -[(6- O -E-feruloyl)- β -D-glucopyranosyl]-(1→2)- β -D-glucopyranoside ( 3 ), kaempferol-3- O -[(6- O -E-caffeoyl)- β -D-glucopyranosyl]-(1→2)- β -D-glucopyranoside ( 4 ), kaempferol-3- O -[(6- O -E-caffeoyl)- β -D-glucopyranosyl]-(1→2)- β -D-glucopyranosyl-7- O - β -D-glucopyranoside ( 5 ), and kaempferol-3- O -[(6- O -p-coumaroyl)- β -D-glucopyranosyl]-(1→2)- β -D-glucopyranosyl- 7 - O - β -D-glucopyranoside ( 6 ), from Asplenium ruprechtii Sa. Kurata, a folk medicine widely used to treat thromboangitis obliterans in China, Japan, and Korea. Based on spectroscopic, mainly 1D-, 2D-NMR and (+)-HRESIMS, analyses as well as through comparisons previous reports, chemical structure of 1 was determined as 3 β ,24,30-tri- β -D-glucopyranosyl-23,25-dihydroxycycloartane. According to 1 H coupling constant of anomeric protons and co-TLC of the acid hydrolysate with D-glucose, all three glycoside groups in 1 are revealed as β -D-glucopyranosyl. Furthermore, SOD-like antioxidant activity evaluation via IC 50 of 12.43, 6.78, 9.12, 6.94 and 4.85 μM reveal that compounds 2 - 6 have bio-activity.