Vicinal ketoesters – key intermediates in the total synthesis of natural products

Abstract

This review summarizes examples for the application of vicinal ketoesters such as α-ketoesters, mesoxalic esters, and α,β-diketoesters as key intermediates in the total synthesis of natural products utilizing their electrophilic keto group as reactive site. Suitable key reactions are, e.g., aldol additions, carbonyl ene reactions, Mannich reactions, and additions of organometallic reagents. The vicinal arrangement of carbonyl groups allows the stabilization of reactive conformations by chelation or dipole control.

Divergent Total Synthesis of Fornicin A, Fornicin D, and Ganodercin D, Meroterpenoids from Ganoderma Mushrooms

“…In order to obtain the unsaturated γ‐ketoacid moiety, an aldol condensation between 7 and 10 was imagined (Scheme 5). [25] However, conventional aldol condensation conditions, i.e. alkoxide and/or acidic reagents, were considered unsuitable with our substrates, as the former would most likely enolize 7 , and the latter would remove the THP groups of 10 .…”