Actinidine is a pyridine derivative found in the essential oil of valerian (Valeriana officinalis) root and Actinidia polygama (silver vine). Actinidine is also a pheromone for a variety of insects. Actinidine is a cat attractant, with effects like those of nepetalactone, the active compound found in catnip. By means of gas chromatographic, mass spectrometric, and micro-preparative methodsN,N-dimethyluracil and actinidine were identified as two ethologically active compounds in the ponerine antMegaponera foetens. The synthesized poison gland compoundN,N-dimethyluracil released trail-following behavior, whereas actinidine, found in the pygidial gland, stimulated ants to leave the nest, possibly in an alarm reaction. Biological activity of the synthetic samples were confirmed by behavioral experiments and electroantennogram responses with worker antennae.