Isolation of Yessotoxin 32-O-[β-l-arabinofuranosyl-(5′→1″)-β-l-arabinofuranoside] from Protoceratium reticulatum

Abstract Yessotoxin 32- O -[β- l -arabinofuranosyl-(5′→1″)-β- l -arabinofuranoside] ( 3 ) was isolated from extracts of Protoceratium reticulatum during a large scale isolation of yessotoxin ( 1 ). The structure was characterized by mass spectrometry and NMR spectroscopy. Di-glycoside- 3 , along with the corresponding mono-glycoside ( 2 ) were detected in cultures of P. reticulatum originating from Europe and New Zealand, suggesting that production of arabinosides of 1 is a normal feature of this alga. Formation of multiply charged anions and fragmentation of 3 occurred much more readily than for 1 and 2 under the LC-MS conditions used in this study.