Acylated flavone C-glycosides from Cucumis sativus

Leaves of Cucumis sativus plants treated with silicon and infected with Sphaerotheca fuliginea yielded five new acylated flavone C-glycosides identified as isovitexin 2″- O-(6‴-( E)- p-coumaroyl)glucoside ( 6), isovitexin 2″- O-(6‴-( E)- p-coumaroyl)glucoside-4′- O-glucoside ( 7), isovitexin 2″- O-(6‴-( E)-feruloyl)glucoside-4′- O-glucoside ( 11), isoscoparin 2″- O-(6‴-( E)- p-coumaroyl)glucoside ( 9), and isoscoparin 2″- O-(6‴-( E)-feruloyl)glucoside-4′- O-glucoside ( 12). The known flavone-glycosides isovitexin ( 1), saponarin ( 2), saponarin 4′- O-glucoside ( 3), vicenin-2 ( 4), apigenin 7- O-(6″- O- p-coumaroylglucoside) ( 5), isovitexin 2″- O-(6‴-( E)-feruloyl)glucoside ( 8) and isoscoparin 2″- O-(6‴-( E)-feruloyl)glucoside ( 10), were also identified in this plant material. Five new acylated flavone C-glycosides have been identified in leaves of Cucumis sativus treated with Si and infected with Sphaerotheca fuliginea.