title: Synthesis and pharmacological properties of morphine congeners having pendant crown ether as an opioid receptor probe.
mesh_terms: D000818:Animals; D055598:Chemical Phenomena; D002621:Chemistry; D004988:Ethers, Cyclic; D009022:Morphine Derivatives / Q000138:chemical synthesis / Q000494:pharmacology*; D011957:Receptors, Opioid / Q000187:drug effects*
chemical_list: D004988:Ethers, Cyclic; D009022:Morphine Derivatives; D011957:Receptors, Opioid