The psymberin unsaturated ‘psymberate’ sidechain 7 was synthesized in 7 steps (36% yield) with good diastereoselectivity using commercially available starting material to control the stereochemistry at C4 and C5. The synthesis of seco-psymberin was completed in an efficient manner based on a CuI mediated coupling reaction between vinyl iodide 8 and ‘psymberamide’ 7. In an attempt to synthesize natural