First Total Synthesis of Varioxiranol A

Abstract

The paper describes the first total synthesis of natural varioxiranol A by chiral pool approach and confirmation of its absolute configuration by single-crystal X-ray analysis. The target varioxiranol A and its 4-epimer were obtained after 10 steps from single and available chiral source 1,2-O-isopropylidene-d-glyceraldehyde in an overall yield of 10% and 6%, respectively. A synthetic strategy based on the Julia–Kocieński coupling reaction between aromatic sulfone and corresponding aldose derivative makes it possible to prepare other interesting polyketide derivatives (varioxiranols B-G, varioxirane, varioxiranediols).

Keywords

• synthesis of natural products
• varioxiranol A
• 4-epi-varioxiranol A
• absolute structure
• Emericella variecolor