DMD mediated formal synthesis of (+/-)-coerulescine.

A highly efficient method for the formal synthesis of the natural product (+/-)-coerulescine 1 from tetrahydro-beta-carboline 3, mediated by dimethyldioxirane (DMD), is described. Compound 15, the N9-demethylated precursor of 1, was prepared from 3 in 4 steps with an overall yield of 95%. The effect of electron withdrawing groups at the N2,N9 atoms of 3 was explored for the oxidative rearrangement step.