Synthesis of 4-Hydroxy-lH-pyrrole-2,3-dicarboxylic Acid Derivatives: Unusual Coupling of Acetylenic Esters and a-Amino Acids in the Presence of Cyclohexyl Isocyanide or N,N'-Dicyclohexylcarbodiimide

摘要

A facile and direct synthetic entry to 4-hydroxy-1 H-pyr-role-2,3-dicarboxylic acid derivatives is reported. It is based on the unusual ring annulation of acetylenic esters and alpha-amino acids with isocyanide or carbodiimide under neutral conditions in a one-step procedure.