FORMAL TOTAL SYNTHESIS OF ENANTIOPURE TRICYCLIC (S)-MYRMICARIN ALKALOIDS 217,215A AND 215B

摘要

We described herein a formal synthesis of the enantiopure tricyclic (4aS)-myrmicarin alkaloids 217, 215A and 215B owing to the obtention of a common pyrroloindolizidine intermediate, starting from a chiral cis-(2S,5R)-disubstituted pyrrolidine. An intramolecular one-pot aldolization-crotonization-aromatization process of a diketo indolizidine constitutes the key step for the formation of the pyrrole ring of the target compound.