homprenorphine homprenorphine homprenorphine (m-5202; r&s-5205-m) is an opioid analgesic of the thebaine series which was synthesized and assayed in 1967, but was not further studied and was never marketed. homprenorphineclinical dataatc codenoneidentifiers iupac name 2-butan-2-ol cas number16549-56-7pubchem cid3084250chemspider2341344uniish57250j2dchemblchembl2104317chemical and physical dataformulac28h37no4molar mass451.607 g·mol−13d model (jsmol)interactive image smiles oc(c)(cc)c7cc63\c=c/c7(oc)c4oc1c2c(ccc1oc)cc6n(ccc234)cc5cc5