Synthesis of SL0101 carbasugar analogues: carbasugars via Pd-catalyzed cyclitolization and post-cyclitolization transformations.

A general approach to the stereoselective synthesis of 5a-carbasugars has been developed. The route mimics our palladium-catalyzed glycosylation/postglycosylation approach to carbohydrates in that it also utilizes a highly regio- and stereospecific palladium-catalyzed allylation and postglycosylation reaction sequence for the installation of either D- or L-cyclitols. This cyclitolization/postcyclitolization sequence was used for the enantioselective synthesis of a cyclitol analogue of SL0101, its D-sugar enantiomer, as well as several acetylation pattern analogues.