5-carboxamidotryptamine 5-carboxamidotryptamine 5-carboxamidotryptamine (5-ct) is a tryptamine derivative closely related to the neurotransmitter serotonin. 5-carboxamidotryptamineidentifiers iupac name 3-(2-aminoethyl)-1h-indole-5-carboxamide cas number74885-09-9 npubchem cid1809iuphar/bps4chemspider1743 yunii91h76044o0chebichebi:48292 ychemblchembl18840 ycomptox dashboard (epa)dtxsid60996379 chemical and physical dataformulac11h13n3omolar mass203.245 g·mol−13d model (jsmol)interactive image smiles c1=cc2=c(c=c1c(=o)n)c(=cn2)ccn inchi inchi=1s/c11h13n3o/c12-4-3-8-6-14-10-2-1-7(11(13)15)5-9(8)10/h1-2,5-6,14h,3-4,12h2,(h2,13,15) ykey:wkzlnewviagnaw-uhfffaoysa-n y ny (what is this?) (verify) 5-ct acts as a non-selective, high-affinity full agonist at the 5-ht1a, 5-ht1b, 5-ht1d, 5-ht5a, and 5-ht7 receptors, as well as at the 5-ht2, 5-ht3, 5-ht6 receptors with lower affinity. it has negligible affinity for the 5-ht1e and 5-ht1f receptors. 5-ct binds most strongly to the 5-ht1a receptor and it was once thought to be selective for this site. recently, a close derivative of 5-ct, ah-494 has been shown to function as an agonist of 5-ht7, although being more selective over 5-ht1a. structural study indicated residue ser5x43 might play critical roles in the selectivity of 5-ct across the serotonin receptor family.