Synthesen von Gallenfarbstoffen, XII. Synthese von <i>E,Z,Z</i>‐konfigurierten Biliverdinen aus entsprechend konfigurierten 5(1<i>H</i>)‐Pyrromethenonen

Abstract

Syntheses of Bile Pigments, XII. Synthesis of E,Z,Z ‐Configurated Biliverdins from 5(1 H )‐Pyrromethenones of the Same Configuration ( Z,Z,Z )‐ and ( E,Z,Z )‐mesobiliverdin IIIα dimethyl esters 4 are obtained by acid‐catalyzed condensation of methyl 5′‐( tert ‐butoxycarbonyl)isoneoxanthobilirubinate with methyl (Z)‐ and ( E )‐5′‐formylisoneoxanthobilirubinate, respectively.