The Structures of Sinapic Acid Esters and Their Metabolism in Cotyledons of Raphanus sativus

Abstract

Five sinapic acid esters were isolated from cotyledons of Raphanus sativus and have been iden­tified with the aid of electron impact (El)-, field desorption (FD)-mass spectrometry and NMR spectroscopy: 6,3′-disinapoylsucrose, sinapoylcholine (sinapine), 6-sinapoylglucoraphenine, 1-si- napoylglucose, and sinapoylmalate. Three of these derivatives are metabolically related in the se­quence sinapoylcholine →1 -sinapoylglucose →sinapoylmalate.