Antioxidant phenolic acids from the leaves of Armeniaca sibirica.

Phytochemical investigation of the leaves of Armeniaca sibirica (L.) Lam. led to the isolation of two new phenolic acids (1-2), together with eight known compounds (3-10) from the ethanol extracts of this plant. Structures of these compounds were elucidated through detailed spectroscopic analyses, using 1D-NMR and 2D-NMR in combination with HR-EI-MS techniques. All the compounds were evaluated for their antioxidant capabilities in vitro using 2, 2'-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS), 1, 1'-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assays, and ferric-reducing antioxidant power (FRAP) methods.