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The first total synthesis of loroxanthin (<b>1</b>) was accomplished by Horner-Wadsworth-Emmons reaction of C₂₅-apocarotenal <b>8</b> having a silyl-protected 19-hydroxy moiety with C₁₅-phosphonate <b>25</b> bearing a silyl-protected 3-hydroxy-ε-end group. Preparation of apocarotenal <b>8</b> was achieved via Stille coupling reaction of alkenyl iodide <b>10</b> with alkenyl stananne <b>9</b>, whereas phosphonate <b>25</b> was prepared through treatment of ally alcohol <b>23</b> with triethyl phosphite and ZnI₂. The ally alcohol <b>23</b> was derived from the known (3<i>R</i>,6<i>R</i>)-3-hydroxy C₁₅-aldehyde <b>20,</b> which was obtained by direct optical resolution of racemate <b>20</b> using a semi-preparative chiral HPLC column.