Studies on the total synthesis of macrolactin A. A stereoselective synthesis of the C3–C13 and C14–C24 fragments

Synthetic studies towards the C3–C13 (2) and C14–C24 (3) segments of the potent antiviral and antitumor compound macrolactin A (1) are presented. Segment 2 was constructed via a convergent and facile approach, exploiting Wittig olefination to generate the sensitive E,Z-diene moiety. Segment 3 was obtained from the chiral pool derived sulfone 4 via an α-alkylation–desulfonation reaction sequence.