Towards the total synthesis of keramaphidin B

Abstract

The enantio- and diastereoselective Michael addition of a δ-valerolactone-derived pronucleophile to a substituted furanyl nitroolefin catalysed by a bifunctional cinchonine-derived thiourea has been used as the key stereocontrolling step in a new synthetic strategy to the heavily functionalised piperidine core of keramaphidin B.

Keywords

• bifunctional organocatalyst
• enantioselective Michael addition
• keramaphidin B
• nitro-Mannich lactamisation cascade