Preliminary SAR studies on non-apamin-displacing 4-(aminomethylaryl)pyrrazolopyrimidine KCa channel blockers

An exploratory SAR study on a series of non-apamin-displacing 4-(aminomethylaryl)pyrazolopyrimidine KCa channel blockers is described, and their selectivity against KCa channel subtypes is reported. The aminomethylthiophene derivative 24, was the most potent analog identified in the series.