Synthetic Studies on the Nhatrangins: Stereoselective Access to an Advanced Aldehyde Intermediate

Two different strategies have been considered to achieve the first total synthesis of nhatrangins A and B. The first approach based on a cross metathesis (CM) reaction was unsuccessful. The second, which combined a highly stereoselective alkylation, a diastereoselective aldolization, and finally an esterification, furnished an advanced aldehyde intermediate bearing the three contiguous stereogenic centres and the expected side‐chain. Two strategies have been considered for the stereoselective synthesis of nhatrangins A and B. A sequence involving diastereoselective alkylation and aldolization employing ephedrine derivatives as chiral auxiliaries was the most efficient approach to deliver a key aldehyde framework.