246510-20-3Relevant articles and documents
Enantioselective total synthesis of altohyrtin C (spongistatin 2)
Evans, David A.,Trotter, B. Wesley,Coleman, Paul J.,Cote, Bernard,Dias, Luiz Carlos,Rajapakse, Hemaka A.,Tyler, Andrew N.
, p. 8671 - 8726 (2007/10/03)
The first total synthesis of a spongipyran macrolide, altohytrin C, is described. The convergent synthesis strategy relies on a regioselective macrolactonization, a stereoselective Wittig coupling of the two major synthetic fragments, a complex anti aldol reaction to join the C1-C15 and C16-C28 spiroketal regions, and an anomeric sulfone acylation to join the C29-C37 and C38-C43 pyran regions. The incorporation of the C44- C51 sidechain in the final stages of the synthesis establishes a viable route for the construction of variants in this pharmacologically important region. Methodological developments en route to the total synthesis include a 1,5 antiselective methyl ketone aldol reaction and a diastereoselective approach to Lewis acid mediated β-C-glycosidation. Completion of the synthesis has confirmed the stereochemical assignments proposed in the altohyrtin series and has established the identity of the altohyrtin and spongistatin marine macrolides.