Singlet oxygen in synthesis. Formation of d,l- and meso-isochrysohermidin from a 3,3′-bipyrrole precursor

Abstract

A synthesis of the d,l and meso forms of isochrysohermidin 3 is outlined which employs the singlet oxygen oxidation of pyrroles as the key step. The bipyrrole precursor 8 was synthesized from a 3-hydroxy monopyrrole which, in turn, was prepared by addition of methylamine to a vinyl vicinal tricarbonyl.