title: Syntheses of unnatural N-substituted UDP-galactosamines as alternative substrates for N-acetylgalactosaminyl transferases.
abstract: UDP-GalNAc analogues with slight modifications in the 2-acetamido group of the GalNAc moiety are prepared in order to study their role in the mechanism of the N-acetylgalactosaminyl transferase mediated glycosylation step. The analogues with N-propionyl-, N-butyryl- and N-bromoacetyl-groups were synthesized, utilizing Khorana's morpholidate coupling method starting from D-galactosaminyl-1-phosphate after selective N-acylation of its amino group with the appropriate N-acyloxysuccinimides. Furthermore, in addition to UDP-galactosamine its 2-azido analogue has been efficiently prepared involving a metal catalyzed diazo transfer reaction.
authors.affiliation: Institut für Organische Chemie, Universität Hamburg, Martin-Luther-King-Platz 6, D-20146 Hamburg, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Lazarevic
authors.forename: Joachim
authors.initials: J
authors.lastname: Thiem
mesh_terms: D006031:Glycosylation; D009682:Magnetic Resonance Spectroscopy; D017350:N-Acetylgalactosaminyltransferases / Q000378:metabolism*; D011485:Protein Binding; D013329:Structure-Activity Relationship; D014536:Uridine Diphosphate N-Acetylgalactosamine / Q000031:analogs & derivatives* / Q000138:chemical synthesis*
chemical_list: D014536:Uridine Diphosphate N-Acetylgalactosamine; D017350:N-Acetylgalactosaminyltransferases