Synthesis and biological activity of a novel class nicotinic acetylcholine receptors (nAChRs) ligands structurally related to anatoxin-a

Department of Pharmaceutical Sciences, University of Ferrara, Via Fossato di Mortara 17/19, 44121 Ferrara, Italy.
Bioorganic & medicinal chemistry letters (Impact Factor: 2.33). 09/2011; 21(18):5423-7. DOI: 10.1016/j.bmcl.2011.06.127
Source: PubMed

ABSTRACT The introduction of the isoxazole ring as bioisosteric replacement of the acetyl group of anatoxin-a led to a new series of derivatives binding to nicotinic acetylcholine receptors. Bulkier substitutions than methyl at the 3 position of isoxazole were shown to be detrimental for the activity. The binding potency of the most interesting compounds with α1, α7 and α3β4 receptor subtypes, was, anyway, only at micromolar level. Moreover, differently from known derivatives with pyridine, isoxazole condensed to azabicyclo ring led to no activity.

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