Synthesis and SAR studies of a novel series of T-type calcium channel blockers Original Research Article

For the novel, potent, and selective T-type Ca2+ channel blockers, a series of sulfonamido-containing 3,4-dihydroquinazoline derivatives were prepared and evaluated for their blocking actions on T- and N-type Ca2+ channels. Among them, 9c (KYS05064, IC50 = 0.96 ± 0.22 μM) was found to be as potent as Mibefradil and also showed the highest selectivity for T-type Ca2+ channel with no effect on N-type Ca2+ channel.