Syntheses, pharmacological evaluation and molecular modelling of substituted 6-alkoxyimidazo[1,2-b]pyridazines as new ligands for the benzodiazepine receptor
摘要:
A series of 2,3-disubstituted-6-alkoxyimidazo[1,2-b] has been synthesized and evaluated for in vitro affinity for the benzodiazepine receptor (BZR). 3-(Benzamidomethyl or substituted benzamidomethyl)-6-methoxy-2-(3,4-methylenedioxyphenyl)imidazo[1,2-b]pyridazines were found to be the most potent BZR ligands (eg, 4a, IC50 7 nM; 4e, IC50 14 nM; 4v, IC50 8 nM). Imidazo[1,2-b]pyridazines unsubstituted in the 3-position, or containing builder alkoxy groups in the 6-position, were found to bind less strongly to the BZR. Selected compounds from the series were identified from in vitro GABA-shift experiments as BZR agonists. Molecular modelling has been employed to identify the common pharmacophoric points of lipophilic and hydrogen bonding, ligand-receptor interaction and areas of steric hindrance for these substituted imidazo[1,2-b]pyridazines at the BZR.
2-Phenylimidazo[1,2-b]pyridazine derivatives highly active against Haemonchus contortus
摘要:
A series of 2-phenylimidazo[1,2-b]pyridazine derivatives were synthesized and evaluated for their in vitro anthelmintic activity against Haemonchus contortus. The most active compounds had in vitro LD(99) values of 30 nM, which is comparable to that of the benchmark commercial nematocide, Ivermectin. (C) 2011 Elsevier Ltd. All rights reserved.