Short diastereoselective synthesis of the C1-C13 (AB spiroacetal) and C17-C28 fragments (CD spiroacetal) of spongistatin 1 and 2 through double chain-elongation reactions.
A unique and practical synthetic sequence for rapid access to polyketides and to further the spiroacetals derived from them, which utilizes a bidirectional Hosomi-Sakurai allylation approach around key allylsilanes in the synthesis of the AB and CD ring systems of spongistatin 1 and 2, is reported. The synthesis of the AB spiroacetal 9 requires 13 steps, with a longest linear sequence of seven steps in an overall yield of 27%. The synthesis of the CD spiroacetal 13 requires 15 steps, with a longest linear sequence of 11 steps in an overall yield of 30%. Both syntheses start from but-3-enol.
Laboratory of Glycochemistry and Asymmetric Synthesis (LGSA), Swiss Institute of Technology (EPFL), Batochime, 1015 Lausanne, Switzerland.
Christopher L
CL
Flowers
Pierre
P
Vogel
D018942:Macrolides / Q000138:chemical synthesis* / Q000737:chemistry*; D015394:Molecular Structure; D013141:Spiro Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism; D000095702:Polyether Toxins
D018942:Macrolides; D013141:Spiro Compounds; C409088:altohyrtin C; D000095702:Polyether Toxins; C083856:spongistatin 1