SYNTHESIS OF OCTYL O-GLYCOSIDE AND S-GLYCOSIDE RELATED TO THE GPI ANCHOR OF TRYPANOSOMA-BRUCEI AND THEIR IN-VITRO GALACTOSYLATION BY TRYPANOSOMAL ALPHA-GALACTOSYLTRANSFERASES

Octyl O- and S-glycosides of mono- to tri-saccharides related to the c ore structure a-D-Manp-(1-->2)-alpha-D-Manp-(1-->6)-alpha-D-Manp of th e GPI anchor of Trypanosoma brucei have been prepared via regioselecti ve protodesilylation and glycodesilylation of octyl O- and S-glycoside s of -1,3-disiloxane-1,3-diyl)-alpha-D-mannopyranoside. The synthetic saccharides have been used as substrates for enzymatic alpha-galactosy lation with membrane fractions of bloodstream forms of T. brucei strai n 427 variants MIT at 1.4, MIT at 1.2, and MIT at 1.5, respectively. ( C) 1996 Elsevier Science Ltd.