Studies on the synthesis of phorboxazole B: stereoselective synthesis of the C28–C46 segment

A stereoselective synthesis of C28–C46 segment of phorboxazole B is described. Key features of the synthetic route involved the use of 1,3-asymmetric induction of Mukaiyama aldol reaction to construct the stereogenic center at C35, and the employment of metalated oxazole chemistry to prepare the ketal 6.