α5ia α5ia α5ia (ls-193,268) is a nootropic drug invented in 2004 by a team working for merck, sharp and dohme, which acts as a subtype-selective inverse agonist at the benzodiazepine binding site on the gabaa receptor. it binds to the α1, α2, α3 and α5 subtypes. α5iaclinical dataother namesls-193,268atc codenoneidentifiers iupac name 3-(5-methylisoxazol-3-yl)-6-triazolophthalazine cas number215874-86-5pubchem cid6918451chemspider5293648unii1m7ni1a92lcomptox dashboard (epa)dtxsid10175950 chemical and physical dataformulac17h14n8o2molar mass362.353 g·mol−13d model (jsmol)interactive image smiles cc1=cc(=no1)c2=nn=c3n2n=c(c4=cc=cc=c43)occ5=cn(n=n5)c inchi inchi=1s/c17h14n8o2/c1-10-7-14(22-27-10)16-20-19-15-12-5-3-4-6-13(12)17(21-25(15)16)26-9-11-8-24(2)23-18-11/h3-8h,9h2,1-2h3key:nzmjfrxkgucynp-uhfffaoysa-n in vivo electrophysiology recordings of local field potentials indicate that oral administration of α5ia increases the amplitude of sharp wave ripples which are implicated in memory function in adult wild type rats. it is intriguing to note that the increase in ripple amplitude is not seen in adult male tgf344-ad rats which express human β-amyloid precursor protein (with the swedish mutation) and human presenilin-1 (with a δ exon 9 mutation).