Endomorphin-2 with a β-Turn Backbone Constraint Retains the Potent μ-Opioid Receptor Agonist Properties
作者:Csaba Tömböly、Steven Ballet、Debby Feytens、Katalin E. Kövér、Attila Borics、Sándor Lovas、Mahmoud Al-Khrasani、Zsuzsanna Fürst、Géza Tóth、Sándor Benyhe、Dirk Tourwé
DOI:10.1021/jm7010222
日期:2008.1.1
The constitutional similarity with different secondary structure preference between the Aba-Gly and the spiro-Aba-Gly scaffolds were exploited to design the novel endomorphin-2 analogs Tyr-spiro-(R/S)-Aba-Gly-Phe-NH2 (1 and 2) and Tyr-(R/S)-Aba-Gly-Phe-NH2 (3 and 4). The (R)-spiro analog 1 was found to be a potent and selective mu-opioid agonist/partial agonist (K-i mu = 29.3 nM, IC50 = 50 nM, K-e = 0.57). NMR experiments and molecular modeling indicated that its backbone adopts mainly a U-turn in aqueous solution.