We now report our results from biosynthetic studies conducted on tetraponerine-6 (T-6) 2a from Tetraponera sp. ants, which show that the two tetraponerine skeletons (1 for tetraponerine-8 (T-8) 1a and 2 for T-6) are assembled via different pathways. Using incorporation experiments with [1,4-14C]putrescine dihydrochloride followed by chemical degradation, evidence is presented showing that T-6 is biosynthesized from two molecules of putrescine and a seven-carbon moiety derived from an eight-carbon polyacetate chain through decarboxylation, in contrast with T-8, which derives from one putrescine unit and a twelve-carbon polyacetate precursor. Specifically, skeleton 1 originates from the condensation of a twelve-carbon polyacetate precursor with one putrescine unit, whereas skeleton 2 is formed by the reaction of two putrescine units with an eight-carbon polyacetate chain with concomitant decarboxylation.