Unified Approach for the Total Synthesis of bis-THF C15 Acetogenins: a Chloroenyne from Laurencia Majuscula, Laurendecumenyne B and Laurefurenynes A/B

A highly diastereoselective total synthesis of several bis-THF C15 acetogenin class of natural products: chloroenyne from Laurencia Majuscula, laurendecumenyne B, laurefurenynes A/B and synthesis of an advanced intermediate reported in the earlier total synthesis of (E/Z)-elatenynes (formal Synthesis) are described. The salient features in the synthesis include epoxide opening, Birch reduction, Sharpless asymmetric dihydroxylation-cycloetherification, SN2 halogenation and a (relay-) cross-metathesis.