The total synthesis of 5-hydroxygoniothalamin is achieved from commercially available l-xylose. The α,β-unsaturated-δ-lactone core is constructed in very good yield by utilizing one-carbon and two-carbon cis-Wittig olefinations and δ-lactonization using Yamaguchi conditions. Subsequent Grubbs cross-metathesis followed by desilylation results in 5-hydroxygoniothalamin.
Key words
C1 Wittig reaction - C2 Wittig reaction - Yamaguchi reaction - cross-metathesis - 5-hydroxygoniothalamin