bu-48 bu-48 bu-48 is a drug that is used in scientific research. it is from the oripavine family, related to better-known drugs such as etorphine and buprenorphine. bu-48identifiers iupac name n-cyclopropylmethyl--cyclohexano-1'-hydroxy-6,14-endo-ethenotetrahydronororipavine pubchem cid10003114chemspider58178410chemical and physical dataformulac27h33no4molar mass435.564 g·mol−13d model (jsmol)interactive image smiles co12c=c3(41(ccc4)o)5cc6ccc(c7c63(2o7)ccn5cc8cc8)o inchi inchi=1s/c27h33no4/c1-31-27-10-9-25(17-3-2-4-18(29)22(17)27)20-13-16-7-8-19(30)23-21(16)26(25,24(27)32-23)11-12-28(20)14-15-5-6-15/h7-10,15,17-18,20,22,24,29-30h,2-6,11-14h2,1h3/t17-,18+,20-,22-,24-,25-,26+,27-/m1/s1key:lmfryupwvalvra-qdftycmysa-n (verify) the parent compound from which bu-48 was derived (with n-methyl rather than methylcyclopropyl on the nitrogen and lacking the aliphatic hydroxyl group) is a powerful μ-opioid agonist 1000 times more potent than morphine, but in contrast bu-48 has only weak analgesic effects and instead acts primarily as a δ-opioid agonist. its main effects are to produce convulsions, but it may also have antidepressant effects.