6002
H. Teng et al. / Bioorg. Med. Chem. Lett. 21 (2011) 5999–6002
binding experiments using [3H]CP55, 940, as the radioligand.29,30
All conformationally constrained analogs had significantly reduced
affinities for both receptors. Interestingly, two analogs AM-7528
(4c) and AM-7536 (4d) originating from direct C4–C60 linkage
exhibited selectivity for both mCB2 and hCB2 receptors compared
to rCB1 receptors.
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To explore the significant loss of affinity of the novel conform-
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Acknowledgments
We are grateful to Pusheng Fan for the radioligand binding as-
says. We are also thankful to David Janero for helpful comments.
This work was supported by Grants from the National Institutes
on Drug Abuse, DA023142 and DA007312.
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