Absolute configuration of the polyazamacrolides, macrocyclic polyamines produced by a ladybird beetle

Article abstract of DOI:10.1016/S0040-4039(98)01404-X

The absolute configuration of the polyazamacrolides, oligomeric macrocycles from the pupal defensive secretion of Epilachna borealis, was determined by comparison of derivatives of the natural material with enantiomerically pure synthetic samples. Samples of a mixture of three (ω- 1)-(2-hydroxy-ethylamino)alkanoic acids and of the corresponding aza-lactones were synthesized from (R)-alaninol. Gas chromatographic comparison of MTPA- amides of the synthetic aza-lactones with the MTPA-amides of aza-lactones prepared from the natural material established that the polyazamacrolides have the (R)-configuration at all stereogenic centers.