Chromatographic Determination of the Absolute Configuration in Sanjoinine A That Increases Nitric Oxide Production

A chiral derivatization strategy with phenylglycine methyl ester (PGME) was employed to develop a straightforward method to determine the absolute configurations of , -dimethyl amino acids. The PGME derivatives were analyzed using liquid chromatography- mass spectrometry to identify the absolute configurations of various , -dimethyl amino acids based on their elution time and order. The established method was applied to assign the absolute configuration of the , -dimethyl phenylalanine in sanjoinine A ( ), a cyclopeptide alkaloid isolated from Zizyphi Spinosi Semen widely used as herbal medicine for insomnia. Sanjoinine A displayed production of nitric oxide (NO) in LPS-activated RAW 264.7 cells.