Synthesis of glyceryl glycosides related to A-type prymnesin toxins. (30th June 2018)

• Record Type: Journal Article
• Authors: Hems, Edward S.; Nepogodiev, Sergey A.; Rejzek, Martin; Field, Robert A.
• Is Part Of: Carbohydrate research. Volume 463(2018)
• Page Start: 14
• Page End: 23
• Publication Date: 2018-06-30
• Subjects: Algae -- Prymnesium parvum -- Toxins -- Prymnesins -- Glyceryl glycosides; Carbohydrates -- Periodicals; Chemistry, Organic -- Periodicals; Biochemistry -- Periodicals; Carbohydrates -- Periodicals; Chimie organique -- Périodiques; Glucides -- Périodiques; Biochemistry; Carbohydrates; Chemistry, Organic; Periodicals; Electronic journals; 507.78
• DOI: 10.1016/j.carres.2018.04.008
• Languages: English
• ISSNs: 0008-6215

Abstract

Abstract: A suite of glycosylated glycerol derivatives representing various fragments of the glycosylated ichthyotoxins called prymnesins were chemically synthesised. Glycerol was used to represent a small fragment of the prymnesin backbone, and was glycosylated at the 2° position with the sugars currently reported to be present on prymnesin toxins. Neighbouring group participation was utilised to synthesise 1, 2- trans -glycosides. SnCl2 -promoted glycosylation with furanosyl fluorides gave 1, 2- cis -furanosides with moderate stereocontrol, whilst TMSOTf promoted glycosylation with a furanosyl imidate gave a 1, 2- cis -furanoside with good stereocontrol. The chemical synthesis of two larger glyceryl diglycoside fragments of prymnesin-1, glycosylated with α-ʟ-arabinopyranose and α-ᴅ-ribofuranose, is also described. As the stereochemistry of the prymnesin backbones at this region is undefined, both the 2 R - and 2 S- glycerol isomers were synthesised. The separated diastereoisomers were distinguished by comparing NOESY NMR with computational models. Graphical abstract: Highlights: Synthesis of glyceryl glycosides inspired by carbohydrates on A-type prymnesins. Di-glycosylated fragments of prymnesin-1 synthesised for bioconjugation studies. NOESY NMR compared with computational models to assign fragment stereochemistry.