| Abstract: | Synthesis of (±)-Lasiodiplodin The synthesis of the plant growth inhibitor (±)-lasiodiplodin (VII), a 12 membered lactone of a substituted resorcylic acid is described. Condensation of methyl acetoacetate and methyl 11-hydroxy-2-undecenoate followed by treatment of the product with benzyl alcohol lead to the benzyl ether II which was aromatized via the benzeneselenenyl derivative. Methylation of the phenolic hydroxyl in III and conversion of the primary alcohol in the side chain into the secondary alcohol provided the hydroxy ester IV. The corresponding hydroxy acid V was transformed into the S-(2-pyridyl) carbothioate which cyclized under the influence of silver ions to yield 68% of 4-benzyl-lasiodiplodin (VI). Removal of the benzyl group by catalytic hydrogenation gave (±)-lasiodiplodin (VII). |
