Reptilian chemistry: Characterization of dianeackerone, a secretory product from a crocodile

The major volatile component in the paracloacal glandular secretion of the adult African dwarf crocodile (Osteolaemus tetraspis) was isolated and char acterized as a 19-carbon aromatic: ketone, dianeackerone (3,7-diethyl-9-phe nyl-2-nonanone). This ketone is absent from the secretion of immatures. Car eful examination of dianeackerone samples isolated from individual adults r evealed that this ketone occurs as both the (3S, 7S) and (3S, 7R) stereoiso mers, with different individuals presenting strikingly different ratios of the isomeric forms. Our initial suspicion that the stereoisomeric dianeacke rones might he indicators of gender proved untenable, leaving the role of t hese glandular constituents a challenge for future study.