200
G. Semple et al. / Bioorg. Med. Chem. Lett. 12 (2002) 197–200
for example, to one of the three aromatic rings, which
may be used to restrict access to the CNS either by
increasing polar surface area and/or decreasing logD.
Their close similarity to the classical KOR agonists
suggests we can exploit existing literature knowledge
regarding the incorporation of such groups into our new
series and such studies with compounds of this type will
be reported in due course.
8. Moran, D. B.; Morton, G. O.; Allbright, J. D. J. Hetero-
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the appropriate radiolabelled ligand from membranes of
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overexpresing the human kappa opioid receptor.
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