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

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.