Convergent highly stereoselective preparation of the C12-C24 fragment of macrolactin A.
The convergent synthesis of the C12-C24 fragment (lower part) of macrolactin A is described. The adapted strategy allowed building up the lower moiety by the assembly of three key intermediates via organometallic addition. One hydroxylic stereogenic center was introduced by the application of chiral sulfoxides methodology on fragment C19-C24. The preparation of the versatile 1,3-anti diol synthon C12-C16 was achieved via opening of chiral epoxide and subsequent oxidation to a hydroxy ketone. Finally, reductive elimination of the appropriate allylic dibenzoate with Na/Hg introduced directly the C16-C19 (E,E)-diene unit, in a highly efficient stereoselective fashion.
Bonini
Carlo
C
Dipartimento di Chimica, Università degli Studi della Basilicata, via N. Sauro 85, 85100 Potenza, Italy. bonini@unibas.it
Chiummiento
Lucia
L
Pullez
Maddalena
M
Solladié
Guy
G
Colobert
Françoise
F
D018942:Macrolides / Q000138:chemical synthesis* / Q000737:chemistry*; D015394:Molecular Structure; D013237:Stereoisomerism
D018942:Macrolides; C453562:macrolactin A