The total synthesis of cytotoxic meroditerpenoid naphthoquinone derivative chabrolonaphthoquinone B (1) in an enantiospecific manner is divulged using a chiral pool approach. The key step of our synthetic route is a modified Julia olefination between a sulfone-bearing aliphatic fragment and a Diels–Alder-derived aromatic aldehyde, leading to the stereoselective construction of the E-trisubstituted double bond.