Systematic (IUPAC) name
(1E,3E)- 5-(2,2-dimethyl- 6-methylenecyclohexyl)- 3-formylpenta- 1,3-dien- 1-yl acetate
Clinical data
Pregnancy cat.  ?
Legal status  ?
CAS number 67656-42-2
ATC code None
PubChem CID 6441116
ChemSpider 4945331 YesY
Chemical data
Formula C17H24O3 
Mol. mass 276.371 g/mol
SMILES eMolecules & PubChem
 YesY(what is this?)  (verify)

Onchidal is a naturally occurring toxin produced as a defensive secretion by the mollusc Onchidella binneyi and several other related species in Onchidella,a genus of small, air-breathing sea slugs. It acts as an irreversible acetylcholinesterase inhibitor, the same mechanism of action as that of the deadly nerve agents, however onchidal is not an organophosphorus or carbamate compound and bears little resemblance to other compounds of this nature.[1]


  1. ^ Abramson SN, Radic Z, Manker D, Faulkner DJ, Taylor P. Onchidal: a naturally occurring irreversible inhibitor of acetylcholinesterase with a novel mechanism of action. Molecular Pharmacology. 1989 Sep;36(3):349-54. PMID 2779521