ABSTRACT
A new method has been developed for the synthesis of chiral 4-carboxyl oxazolidinones by the catalytic asymmetric aldol reaction of an isocyanatomalonate diester with an aldehyde in the presence of a thiourea catalyst. The resulting chiral 4-carboxyl oxazolidinones are the equivalent of ß-hydroxy-α-amino acids bearing a tri- or tetrasubstituted carbon center at their α position. With this in mind, this procedure was successfully applied to the first total synthesis of mycestericin C, which was completed in 12 steps and represents one of the shortest reported sequences for the construction of natural products of this type.
Subject(s)
Biological Products/chemical synthesis , Eicosanoic Acids/chemical synthesis , Oxazolidinones/chemical synthesis , Aldehydes/chemistry , Amino Acids/chemical synthesis , Biological Products/chemistry , Catalysis , Eicosanoic Acids/chemistry , Molecular Structure , Oxazolidinones/chemistry , Stereoisomerism , Thiourea/chemistryABSTRACT
A facile and catalytic asymmetric synthesis of the pentacyclic core of (-)-nakadomarin A, containing all the stereogenic centers of the natural product was achieved. The key intermediate involves the oxazolidine moiety as an iminium cation equivalent. An efficient method for the removal of the N-hydroxyethyl group is also described.
