Three acylated flavone glycosides from Sideritis syriaca.

From the aerial parts of Sideritis syriaca a new flavone glycoside, 5,8,3'-trihydroxy-4'-methoxyflavone 7-(6"'-O-acetylsophoroside) was identified together with apigenin 7-(6"-p-coumaroylglucoside) and apigenin 7-(4"-p-coumaroylglucoside) which are reported for the first time in the genus Sideritis. The compounds were characterized using 1H NMR, 13C NMR, MS and chemical methods.