New kaempferol 3,7-diglycosides from Asplenium ruta-muraria and Asplenium altajense.

A flavonoid was isolated from the fronds of Asplenium ruta-muraria and A. altajense (Aspleniaceae) collected in the Altai Mountains and adjacent area. The compound was identified as kaempferol 3-O-ß-[(6'''-E-caffeoylglucopyranosyl)-(1-->3)-glucopyranoside]-7-O-ß-glucopyranoside (1) by UV, 1H and 13C NMR spectroscopy, LC-MS, and acid and alkaline hydrolyses. Another flavonoid (2) was isolated from A. altajense, as a minor compound, together with 1 and identified as deacylated compound 1, i.e. kaempferol 3-O-laminaribioside-7-O-glucoside. They were found in nature for the first time.