Theoretical Synthesis of Biyouyanagin A Maryon Ginisty Kim Laberge Miguel St-Onge David Marcoux Guillaume Barbe Université de Montréal March 20th 2007

Retrosynthetic Analysis

Synthesis of R4

Synthesis of R5

Synthesis of R3

Synthesis of R2

Synthesis of R1 Thermodynamic enolization –All cis configuration –Tri-substituted alkene Kinetic enolization (system conformation) –The conformation of the system may position suitably a methylene proton for kinetic cis,cis diene formation

Synthesis of R1

Synthesis of Biyouyanagin A

Theoric total synthesis in 22 linear steps Key Steps include NHK macrocyclisation and transannular [2+2] cycloaddition Chiral auxiliaries approach (Myers and Meyers) Conclusion