Clinical data
ATC code
  • none
  • N'-[2-(3-methoxyphenoxy)propyl]-2-(3-methylphenyl)ethanimidamide
CAS Number
PubChem CID
CompTox Dashboard (EPA)
Chemical and physical data
Molar mass312.413 g·mol−1
3D model (JSmol)
  • CC1=CC(=CC=C1)CC(=NCC(C)OC2=CC=CC(=C2)OC)N
  • InChI=1S/C19H24N2O2/c1-14-6-4-7-16(10-14)11-19(20)21-13-15(2)23-18-9-5-8-17(12-18)22-3/h4-10,12,15H,11,13H2,1-3H3,(H2,20,21) ☒N
 ☒NcheckY (what is this?)  (verify)

Xylamidine is a drug which acts as an antagonist at the 5HT2A receptor, and to a lesser extent at the 5HT1A receptor. It does not cross the blood–brain barrier, which makes it useful for blocking peripheral serotonergic responses like cardiovascular[1][2] and gastrointestinal effects,[3] without producing the central effects of 5HT2A blockade such as sedation, or interfering with the central actions of 5HT2A agonists.[4]


Xylamidine is an amidine which serves as a serotonin inhibitor. This agent is prepared by alkylation of 3-methoxyphenol (m-methoxyphenol) with α-chloropropionitrile, KI and potassium carbonate in MEK to give #, which is in turn reduced with lithium aluminium hydride to give the primary amine #. When # is treated with m-tolylacetonitrile in the presence of anhydrous HCl, the synthesis is completed. Alternately, one can react primary amine # with m-tolylacetamidine under acid catalysis to produce xylamidine.


  1. ^ Fuller RW, Kurz KD, Mason NR, Cohen ML (June 1986). "Antagonism of a peripheral vascular but not an apparently central serotonergic response by xylamidine and BW 501C67". European Journal of Pharmacology. 125 (1): 71–7. doi:10.1016/0014-2999(86)90084-1. PMID 3732393.
  2. ^ Dedeoğlu A, Fisher LA (December 1991). "Central and peripheral injections of the 5-HT2 agonist, 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane, modify cardiovascular function through different mechanisms". The Journal of Pharmacology and Experimental Therapeutics. 259 (3): 1027–34. PMID 1762059.
  3. ^ Baker BJ, Duggan JP, Barber DJ, Booth DA (May 1988). "Effects of dl-fenfluramine and xylamidine on gastric emptying of maintenance diet in freely feeding rats". European Journal of Pharmacology. 150 (1–2): 137–42. doi:10.1016/0014-2999(88)90759-5. PMID 3402534.
  4. ^ Dave KD, Quinn JL, Harvey JA, Aloyo VJ (March 2004). "Role of central 5-HT2 receptors in mediating head bobs and body shakes in the rabbit". Pharmacology, Biochemistry, and Behavior. 77 (3): 623–9. doi:10.1016/j.pbb.2003.12.017. PMID 15006475. S2CID 25205829.