Divergent and Selective Functionalization of 2-Formylpyrrole and its Application in the Total Synthesis of the Aglycone Alkaloid Pyrrolemarumine

Diverse 1,2- and 1,2,5-substituted pyrroles were efficiently prepared through a regioselective functionalization of 2-formylpyr-role ( 5a ). This methodology was applied for the first total synthesis of pyrrolemarumine ( 4b ), the aglycone of the corresponding natural pyr-role alkaloid 4”-O-a-L-rhamnopyranoside. The synthesis of 4b was achieved starting from 5a through a seven-step process in 28% over-all yield.