CHEMISTRY OF VENOM ALKALOIDS IN THE ANT GENUS MEGALOMYRMEX

Chemical analyses of three species in the Neotropical ant genus Megalomyrmex have identified this taxon as the third myrmicine genus to produce alkaloids as major venom products. Workers of M. leoninus and workers and ergatoids of M. goeldii produce one or more of four trans-2,5-dialkylpyrrolidines previously identified in other myrmicine genera. M. modestus, on the other hand, is distinctive in producing the novel alkaloid (5E,8E)-3-butyl-5-hexylpyrrolizidine (5d), whose structure was established using a micro-Hofmann degradation sequence. The relationship of Megalomyrmex to other alkaloid-producing ant genera is discussed along with the possible chemotaxonomic significance of the analyzed species when viewed in terms of the recognized species groups in this genus.