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

2. Retrosynthetic Analysis

3. Synthesis of R4

11. Synthesis of R5

15. Synthesis of R3

17. Synthesis of R2

18. 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

19. Synthesis of R1

21. Synthesis of Biyouyanagin A

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