1H-4(5)-SUBSTITUTED IMIDAZOLE DERIVATIVES, THEIR PREPARATION AND THEIR USE AS HISTAMINE H3 RECEPTOR LIGANDS

摘要

Compounds of formula (I) wherein R1 is selected from C¿1? to C6 alkyl, C1 to C6 alkoxy, C1 to C6 alkylthio, carboxy, carboxy (C1 to C6)alkyl, formyl, C1 to C6 alkylcarbonyl, C1 to C6 alkylcarbonylalkoxy, nitro, trihalomethyl, hydroxy, amino, C1 to C6 alkylamino, di(C1 to C6 alkyl)amino, aryl, C1 to C6 alkylaryl, halo, sulfamoyl and cyano; R?2 is C¿1 to C20 hydrocarbylene, in which one or more hydrogen atoms may be replaced by halogen atoms and up to 6 carbon atoms may be replaced by oxygen, nitrogen or sulfur atoms, provided that R2 does not contain a -O-O- group, and provided also that the atom in R2 which is linked to the -SO¿2?- moiety is a carbon atom; R?3¿ is hydrogen or C¿1? to C15 hydrocarbyl, in which one or more hydrogen atoms may be replaced by halogen atoms and up to 3 carbon atoms may be replaced by oxygen, nitrogen or sulfur atoms, provided that R?3¿ does not contain a -O-O- group; X is a bond or -NR4-, wherein R4 is hydrogen or non-aromatic C¿1? to C5 hydrocarbyl (in which one or more hydrogen atoms may be replaced by halogen atoms and up to 2 carbon atoms may be replaced by oxygen, nitrogen or sulfur atoms, provided that R?4¿ does not contain a -O-O- group), aryl(C¿1? to C3)alkyl or R?4¿ represents a bond to R2; and a is from 0 to 2, and their pharmaceutically acceptable salts are useful as histamine H¿3? receptor ligands.