ly-320,135 ly-320,135 ly-320,135 is a drug used in scientific research which acts as a selective antagonist of the cannabinoid receptor cb1. it was developed by eli lilly and company in the 1990s. ly-320,135identifiers iupac name 4-benzonitrile cas number176977-56-3pubchem cid5311257iuphar/bps742chemspider4470772uniicjy03984ctchemblchembl411481echa infocard100.190.302 chemical and physical dataformulac24h17no4molar mass383.395 g·mol−13d model (jsmol)interactive image smiles c3cc(oc)ccc3-c2oc1cc(oc)ccc1c2c(=o)c4ccc(c#n)cc4 inchi inchi=1s/c24h17no4/c1-27-18-9-7-17(8-10-18)24-22(20-12-11-19(28-2)13-21(20)29-24)23(26)16-5-3-15(14-25)4-6-16/h3-13h,1-2h3key:rynsgdfwbjwwsz-uhfffaoysa-n (verify) ly-320,135 displays fairly good selectivity, with a binding affinity for cb1 around 70x stronger than for cb2, but both its potency and selectivity are modest compared to newer agents, and at higher doses it also binds to a range of non-cannabinoid receptors. however ly-320,135 is still fairly widely used in research, particularly for elucidating the mechanisms by which many cb1 antagonists act as inverse agonists at higher doses.