文摘
Analysis of the extracts of male ants of Monomorium minimum and Monomorium ebeninum by GC−MS and GC−FTIR revealed the presence of tyramides 2 and 4c, for which the structures were established by comparison with synthetic samples. These compounds and their analogues 1 and 3 were also found in males of other Monomorium species, males of Myrmicaria opaciventris, and males of several Solenopsis (Diplorhoptrum) species. Vapor-phase FTIR spectra revealed critically important structural clues to two of the tyramides, which had methyl branching in the tyramide acyl moiety. Tyramide 4c exhibited a strong intramolecular amide NH hydrogen bond where an α-keto group was deduced to be present in the acyl moiety and also showed the overlap of this ketone group frequency with that of the amide νC═O. The biological function of these compounds is uncertain; however, their role in ant-mating behavior may be suggested by a large body of evidence.