EA3167 27feb.gif
  • 1-Azabicyclo[2.2.2]octan-8-yl 2-cyclopentyl-2-hydroxy-2-phenylethanoate
CAS Number
PubChem CID
CompTox Dashboard (EPA)
Chemical and physical data
Molar mass331.456 g·mol−1
3D model (JSmol)
  • C1CCC(C1)C(C2=CC=CC=C2)(C(=O)OC3CN4CCC3CC4)O
  • InChI=1S/C20H27NO3/c22-19(24-18-14-21-12-10-15(18)11-13-21)20(23,17-8-4-5-9-17)16-6-2-1-3-7-16/h1-3,6-7,15,17-18,23H,4-5,8-14H2

EA-3167 is a potent and long-lasting anticholinergic deliriant drug, related to the chemical warfare agent 3-quinuclidinyl benzilate (QNB). It was developed under contract to Edgewood Arsenal during the 1960s as part of the US military chemical weapons program, in an attempt to develop non-lethal incapacitating agents. EA-3167 has identical effects to QNB, but is even more potent and longer-lasting, with an effective dose when administered by injection of as little as 2.5 μg/kg (i.e. 0.2 milligrams for an 80 kg person), and a duration of 120–240 hours (5–10 days).[1][2] However unlike QNB, EA-3167 was never weaponized or manufactured in bulk.

Stereoisomers of EA-3167 have also been synthesized under the codename HL-031120.[3]

See also


  1. ^ Wills H (1982). "Appendix I: Digest Report -- Anticholinergic Chemicals". In National Research Council (U.S.). Committee on Toxicology (ed.). Possible Long-Term Health Effects of Short-Term Exposure to Chemical Agents. Vol. 1. Washington, D.C.: National Academies Press. pp. 195–196. OCLC 35472774.
  2. ^ Ketchum JS (2006). Chemical Warfare Secrets Almost Forgotten. A Personal Story of Medical Testing of Army Volunteers with Incapacitating Chemical Agents During the Cold War. ChemBooks. ISBN 978-1-4243-0080-8.
  3. ^ Liu YM, Liu H, Zhong BH, Liu KL (2006). "Stereoselective Synthesis of the Optical Isomers of a New Muscarinic Receptor Antagonist, HL‐031120". Synthetic Communications. 36 (13): 1815–1822. doi:10.1080/00397910600602453. S2CID 96011273.