Short, Stereoselective Synthesis of the Naturally Occurring Pyrrolidine Radicamine B and a Formal Synthesis of Nectrisine

A short, stereoselective synthesis of the naturally occurring pyrrolidine radicamine B is reported. Garner′s (R)-aldehyde, prepared from d-serine, was the chiral starting material. The pyrrolidine ring was stereoselectively created in a very efficient way through a five-step, one-pot transformation. In addition, an intermediate of this synthesis was transformed into an intermediate of a previously published synthesis of the potent α-glucosidase inhibitor nectrisine.