Total synthesis of the proposed structure of lepadiformine via intramolecular N-acylnitroso Diels–Alder reaction

A stereocontrolled approach to the proposed structure of lepadiformine has been achieved employing an intramolecular hetero Diels–Alder reaction of an N-acylnitroso compound, in which syn-face selectivity was controlled. The NMR data of the product synthesized based on this approach is not identical with those reported for natural lepadiformine. Thus, the proposed structure for natural lepadiformine must be revised.