S. Galiano et al. / Bioorg. Med. Chem. Lett. 14 (2004) 597–599
599
Table 2. Y1 and Y5 receptor binding affinities of compounds 6a–g
We are continuing our search for in vivo assays to that
will allow us to clearly understand the SAR trends and
the absorption and permeability to brain.
In summary, we have developed a new series of thio-
phene and benzo[b]thiophene derivatives as potent and
selective antagonists at the human NPY Y5 receptor.
Based on the obtained data, we propose a more thor-
ough research program regarding the determination of
the importance of the substituents Ar1 with in vivo
assays, the biological significance of the results
obtained, and the role played by neuropeptide Y in food
intake response.
Compd
6a
Ar1–SO2–NH–
Y1 IC50 (nM)
>104
Y5 IC50 (nM)
175
6b
>104
28.4
6c
6d
>104
>104
279
42.9
Acknowledgements
We would like to thank Carmen Elizalde for her colla-
boration in this study.
6e
>104
142
6f
>104
>104
11.5
92.2
References and notes
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