Synthesis of 2-hydroxy-3-methylbut-3-enyl substituted coumarins and xanthones as natural products. Application of the Schenck ene reaction of singlet oxygen with ortho-prenylphenol precursors - Helesbeux, J J; Duval, O; Dartiguelongue, C; Séraphin, D; Oger, J M; Richomme, P (Tetrahedron, 2004)