(2-Arylethenyl)-1,3,5-triazin-2-amines as a novel histamine H4 receptor ligands.

Abstract Within the constantly growing number of histamine H 4 (H 4 R) receptor ligands there is a large group of azine derivatives. A series of novel compounds in the group of 4-methylpiperazine-1,3,5-triazine-2-amines were designed and obtained. Considered structures were modified at the triazine 6-position by introduction of variously substituted arylethenyl moieties. Their affinities to histamine H 4 receptors were evaluated in radioligand binding assays with use of Sf 9 cells, transiently expressing human H 4 R. Pharmacological studies results allowed to identify 4-[( E )-2-(3-chlorophenyl)ethenyl]-6-(4-methylpiperazin-1-yl)-1,3,5-triazin-2-amine ( K i  = 253 nM) as the most potent compound in the present series.