Modulating the Serotonin Receptor Spectrum of Pulicatin Natural Products
摘要:
Serotonin (5-HT) receptors are important in health and disease, but the existence of 14 subtypes necessitates selective ligands. Previously, the pulicatins were identified as ligands that specifically bound to the subtype 5-HT2B in the 500 nM to 10 mu M range and that exhibited in vitro effects on cultured mouse neurons. Here, we examined the structure activity relationship of 30 synthetic and natural pulicatin derivatives using binding, receptor functionality, and in vivo assays. The results reveal the 2-arylthiazoline scaffold as a tunable serotonin receptor-targeting pharmacophore. Tests in mice show potential antiseizure and antinociceptive activities at high doses without motor impairment.
A mild high yielding synthesis of oxazole-4-carboxylate derivatives
作者:Paula M.T. Ferreira、Elisabete M.S. Castanheira、Luís S. Monteiro、Goreti Pereira、Helena Vilaça
DOI:10.1016/j.tet.2010.09.014
日期:2010.11
Several 2,5-disubstituted oxazole-4-carboxylates were prepared in high yields from the methyl esters of N-acyl-beta-halodehydroaminobutyric acid derivatives by treatment with a 2% solution of DBU in acetonitrile. The scope of this reaction was investigated and it was found that dehydrodipeptides having a beta-bromodehydroaminobutyric acid residue gave the corresponding oxazoles in good yields. The photophysical properties of some of the oxazoles prepared were studied in four solvents of different polarity. All compounds have reasonable high fluorescence quantum yields and a moderate solvent sensitivity, which makes them good candidates to be used as fluorescent probes. One of the fluorescent oxazoles prepared was inserted after cleavage of the methyl ester into two model peptides using a conventional solution phase strategy. The photophysical properties of the labelled peptides were studied in ethanol and water and compared with those of the oxazole. The results obtained showed that the oxazole maintains a good fluorescence level and the same solvent sensitivity when linked to a peptide chain. (C) 2010 Elsevier Ltd. All rights reserved.