(EN) $i(Inter alia), a direct method for the regioselective sulfation of an organic molecule having optionally derivatized hydroxyl groups at least on two adjacent carbon atoms characterised in that it comprises the treatment of a di-(optionally substituted alkyl and/or aryl) stannylene acetal derivative thereof with an electrophilic sulfating agent is disclosed.(FR) L'invention concerne entre autres un procédé direct de sulfatation régiosélective d'une molécule organique ayant éventuellement des groupes dérivés hydroxyle au moins sur deux atomes de carbone adjacents, et se caractérisant en ce qu'il comprend le traitement d'un dérivé d'acétal de stannylène di(alkyle et/ou aryle éventuellement substitué) avec un agent de sulfatation électrophile.
Methyl α- and β-D-galactopyranosides and 4-O-β-D-galactopyranosyl-3,6-anhydro-L-galactose dimethylacetal were sulfated with sulfuric acid and dicyclohexylcarbodi-imide as a condensation reagent. The sulfated sugars were isolated by ion-exchange chromatography, characterized, and assigned by methylation analyses. On the basis of the yield of each sulfated product that was isolated, sulfation on O-6 appeared to be predominant.