Procyanidins and Phlobatannins from the Twigs of <i>Rosa multiflora</i> and Their Neuroprotective Activity
Tae Hyun Lee, Seong‐Min Hong, Da Hye Yoon, Sun Yeou Kim, Chung Sub Kim, Kang Ro Lee
Abstract
Three new procyanidins (1–3), two new phlobatannins (6 and 7), a new flavan-3,4-diol glycoside (9), and a new neolignan glycoside (10), along with three previously reported compounds (4, 5, and 8) were isolated from the twigs of Rosa multiflora. The chemical structures of the new compounds (1–3, 6, 7, 9, and 10) were characterized by spectroscopic data interpretation, including NMR (1H and 13C NMR, 1H–1H COSY, HSQC, HMBC, and NOESY) and HRESIMS analysis. Experimental ECD data analysis was conducted to assign the absolute configurations of the new compounds (1–3, 6, 7, 9, and 10). The absolute configuration of the sugar moieties was verified through a chiral derivatization method and LC-MS analysis. All the isolated compounds (1–10) were evaluated for their anti-neuroinflammatory activity based on inhibitory effects on nitric oxide production using a lipopolysaccharide-stimulated murine microglia BV-2 cell line and for their neurotrophic effects on nerve growth factor induction in C6 glioma.