in the pygidialgland secretion of Stenus cicindeloides. The three metabolites follow the same biosynthetic pathway, where the N-heterocyclic ring is derived from L-lysine and the side chain from L-isoleucine. The different alkaloids are finally obtained by few modifications of shared precursor molecules, such as 2,3,4,5-tetrahydro-5-(2-methylbutylidene)pyridine (1). This piperideinealkaloid was synthesized