A Biologically Active Analog of the Sex Pheromone of the Emerald Ash Borer, Agrilus planipennis P. J. Silk 1 & K. Ryall 2 & P. Mayo 1 & D. I. MaGee 3 & G. Leclair 1 & J. Fidgen 2 & R. Lavallee 4 & J. Price 1 & J. McConaghy 1 Received: 4 December 2014 /Revised: 9 February 2015 /Accepted: 27 February 2015 /Published online: 20 March 2015 # Abstract The emerald ash borer, Agrilus planipennis (Coleoptera: Buprestidae) (EAB), is an invasive species caus- ing unprecedented levels of mortality to ash trees in its intro- duced range. The female-produced sex pheromone of EAB has been shown to contain the macrocyclic lactone (3Z)- dodecen-12-olide. This compound and its geometrical isomer, (3E)-dodecen-12-olide, have been demonstrated previously to be EAG active and, in combination with a host-derived green leaf volatile, (3Z)-hexenol, to be attractive to male EAB in green prism traps deployed in the ash tree canopy. In the current study, we show that the saturated analog, dodecan- 12-olide, is similarly active, eliciting an antennal response and significant attraction of EAB in both olfactometer and trapping bioassays in green traps with (3 Z)-hexenol. Conformational modeling of the three lactones reveals that their energies and shapes are very similar, suggesting they might share a common receptor in EAB antennae. These find- ings provide new insight into the pheromone ecology of this species, highlighting the apparent plasticity in response of adults to the pheromone and its analog. Both of the unsaturat- ed isomers are costly to synthesize, involving multistep, low- yielding processes. The saturated analog can be made cheaply, in high yield, and on large scale via Mitsunobu esterification of a saturated ω-hydroxy acid or more simply by Baeyer- Villiger oxidation of commercially available cyclododecanone. The analog can thus provide an inexpen- sive option as a lure for detection surveys as well as for pos- sible mitigation purposes, such as mating disruption. Keywords Dodecan-12-olide . (3Z)-dodecen-12-olide . Lactone pheromone . Agrilus planipennis . Analog . Buprestidae . Invasive insect Introduction The emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is an invasive beetle originating from Asia that has now killed tens of millions of ash, Fraxinus spp. (Oleaceae) trees in the USA and Canada (Haack et al. 2002). It was first detected in 2002 in Detroit, MI, USA (Cappaert et al. 2005), but has been present in North America since at least the early 1990s (Siegert et al. 2014). It has not been identified as a pest in its native range of China, Japan, Korea, Mongolia, or eastern Russia (EAB 2014). At the time of its discovery in North America, little was known about the chemical ecology of this species with respect to its host and/or mate-finding behavior. Monitoring of its rapid spread has proven difficult, and improved detection methods and tools are urgently required (Crook and Mastro 2010; Silk and Ryall 2014). Moreover, current management strategies have been limited to tree injections and tree removal in at- tempts to slow the spread or reduce the level of mortality caused by this insect in ash trees (McCullough and * P. J. Silk psilk@nrcan-rncan.gc.ca 1 Canadian Forest Service - Atlantic Forestry Centre, Natural Resources Canada, 1350 Regent Street, Fredericton, NB E3B 5P7, Canada 2 Canadian Forest Service - Great Lakes Forestry Centre, Natural Resources Canada, 1219 Queen Street East, Sault Ste. Marie, ON P6A 2E5, Canada 3 Department of Chemistry, University of New Brunswick, Fredericton, NB E3B 6E2, Canada 4 Ressources Naturelles Canada/ Natural Resources Canada, Service Canadien des Forêts/Canadian Forest Service, CP 10380 Succ Sainte-Foy, Succ. Ste-Foy 1055 du PEPS, PO Box 10380, Québec, QC G1V 4C7, Canada J Chem Ecol (2015) 41:294–302 DOI 10.1007/s10886-015-0562-1 Her Majesty the Queen in Right of Canada 2015