Desymmetrization of trehalose via regioselective DIBAL reductive ring opening of benzylidene and substituted benzylidene acetals

Trehalose dibenzylidene and substituted dibenzylidene acetals were reductively opened either at O6 or O4 in a regioselective manner by using a DIBAL stock solution prepared in toluene or dichloromethane, respectively, to achieve desymmetrization of the trehalose core. The method was applied to synthesize various biologically important unsymmetrically substituted trehalose glycoconjugates, including a mycobacterial trisaccharide, a 4-epi-trehalosamine analog and a maradolipid.