Activity of N-Methyl-a- and -β-funaltrexamine at Opioid Receptors

M. S. Mohamed, D. L. Larson, P. S. Portoghese, A. E. Takemori

Research output: Contribution to journalArticlepeer-review

11 Scopus citations


The N-methyl analogues (2a, 2b) of the nonequilibrium μ opioid receptor antagonist β-funaltrexamine (lb) were synthesized and evaluated in the guinea pig ileum preparation (GPI). These analogues are highly potent, reversible opioid agonists and possess no nonequilibrium antagonist activity. The ineffectiveness of 2b in protecting against irreversible blockage of μopioid receptors by lb and the fivefold lower reactivity of 2b with cysteine suggest that N-methyl substitution adversely affects both the first and second recognition steps that are essential for effective covalent blockage of opioid receptors.

Original languageEnglish (US)
Pages (from-to)1551-1553
Number of pages3
JournalJournal of medicinal chemistry
Issue number8
StatePublished - 1986


Dive into the research topics of 'Activity of N-Methyl-a- and -β-funaltrexamine at Opioid Receptors'. Together they form a unique fingerprint.

Cite this