Synthesis and Determination of Absolute Configuration of Lentztrehalose A

The synthesis of lentztrehalose A, a naturally occurring trehalose derivative exhibiting various biological activities including autophagy-inducing activity, was achieved. The synthesis commenced with the selective protection of hydroxyl groups of commercially available trehalose, followed by the introduction of the side chain moiety by two methods: 1) prenylation and successive diastereoselective dihydroxylation; or 2) etherification by opening of the chiral epoxide. The present synthetic study clarified the unreported absolute configuration of the secondary alcohol part in the side chain portion.