Studies toward funiculosin. Intramolecular carbonyl condensations using carboxamidimidazolide intermediates

Abstract

Internal enolate condensations, utilizing carboxamidimidazoles as activated ureas, provide a general synthesis of the 3,5-disubstituted-4-hydroxy-2-pyridinone 2 as found in funiculosin. The novel all- syn-cyclitol, C-liniked to the heterocyclic system, is prepared from croconic acid.