The syntheses of various fluorinated MUC1 glycopeptide antigens and their specific binding to serum antibodies from mice immunized with natural and fluorinated TF(6)-MUC1-TTox conjugate vaccines are presented.

MUC1-type glycopeptides have already shown their potential as possible cancer vaccine candidates. In addition, first examples of fluorinated antigen structures, especially containing the Thomsen-Friedenreich antigen, with similar antibody recognition have been reported. Using microreactor techniques for improvement of the crucial step, the complex glycosylation reactions, is an efficient way to find optimized reaction parameter as well as to circumvent well-known scale-up drawbacks. Besides, this is the first report of continuous flow glycosylations of glycosyl amino acids, in particular with fluorinated glycosyl building blocks.

Selectively 6-fluorinated analogs of the tumor-associated T(N) antigen Fmoc-Thr(α-O-GalNAc)-OtBu can be efficiently prepared using DAST-mediated de(hydr)oxyfluorination reactions of preformed and orthogonally protected glycosyl amino esters without affecting the labile protecting groups and O-glycosidic linkages. The resulting mono- and difluorinated T(N) analogs are interesting building blocks for non-hydrolyzable mucin-type antigen mimetics, as illustrated by the unprecedented synthesis of two different multiply fluorinated Thomsen-Friedenreich derivatives. The reported deoxyfluoro antigen analogs represent important functional probes for carbohydrate-binding proteins and glycosyl-processing enzymes.