Short syntheses of (±)-tetraponerines-5 and -6. the structures of tetraponerines-1 and -2, and a revision of the structures of (+)-tetraponerines-5 and -6

Abstract

The structures and absolute configurations of (+)-tetraponerines-5 and -6 [(+)-T-5 and (+)-T-6], from the poison gland of the ant Tetraponera sp., were reassigned as 7 and 8, respectively, on the basis of extensive two-dimensional NMR and CD studies. These results led to structure proposals 9 for T-1 and 10 for T-2, the two minor alkaloids of the venom. The structures and relative configurations of T-5 and T-6 were subsequently confirmed by short stereoselective syntheses.