New Flavonoids from Serratula coronata L.

The composition of flavonoids (glycosides) isolated from leaves of Serratula coronata L. s. l. (crowned saw-wort) growing in Primorsky Krai was investigated. Liquid extraction and preparative column chromatography isolated for the first time the flavonoids 3-methylquercetin-3′- O-β-D-glucuronopyranoside [5-(5,7-dihydroxy-3-methoxy-4-oxo-4 H-chromen-2-yl)-2-hydroxyphenylhexopyranosideuronic acid] and quercetin- 3′- O-β-D-glucuronopyranoside [2-hydroxy-5-(3,5,7-trihydroxy-4-oxo-4 H-chromen-2-yl)phenylhexopyranosideuronic acid]. The structures of the isolated compounds were elucidated and proved using UV and NMR spectroscopy and mass spectrometry with electrospray ionization. The flavonoid 3-methylquercetin-3′- O-β-D-glucuronopyranoside was new and not previously described in the literature. S. coronata grows abundantly in Primorsky Krai and could be considered a renewable and promising source for producing flavonoids. [ABSTRACT FROM AUTHOR]