Synthetic studies toward Phorboxazole A. Stereoselective synthesis of the C3-C19 and C20-C32 subunits

Article abstract of DOI:10.1016/S0040-4039(99)00209-9

A stereocontrolled synthesis of two fragments comprising the macrocyclic core of Phorboxazole A is described. The C₃-C₁₉ bis-pyran segment is prepared utilizing reiterative enantioselective allylations from homochiral allylstannanes followed by stereoselective cyclizations. The pentasubstituted tetrahydropyran of the C₂₀-C₃₂ fragment is prepared via an intramolecular stereoselective cationic cyclization of a methoxymethyl ether derivative.