title: Fluorescent ligands for the histamine H2 receptor: synthesis and preliminary characterization.
abstract: 3-[3-(Piperidinomethyl)phenoxy]alkyl, N-cyano-N'-[omega-[3-(1-piperidinylmethyl)phenoxy]alkyl]guanidine and 2-(5-methyl-4-imidazolyl)methyl thioethyl derivatives containing fluorescent functionalities were synthesized and the histamine H2 receptor affinity was evaluated using the H2 antagonist [125I]-aminopotentidine. The compounds exhibited weak to potent H2 receptor affinity with pKi values ranging from <4 to 8.85. The highest H2 receptor affinity was observed for N-cyano-N'-[omega-[3-(1-piperidinylmethyl)phenoxy]alkyl]guanidines substituted with methylanthranilate (13), cyanoindolizine (6) and cyanoisoindole (11) moieties via an ethyl or propyl linker.
authors.affiliation: Pharmaceutical Chemistry, North-West University, Potchefstroom 2520, South Africa. fchsfm@puk.ac.za
authors.forename: Sarel F
authors.initials: SF
authors.lastname: Malan
authors.forename: Andre
authors.initials: A
authors.lastname: van Marle
authors.forename: Wiro M
authors.initials: WM
authors.lastname: Menge
authors.forename: Valentina
authors.initials: V
authors.lastname: Zuliani
authors.forename: Valentina
authors.initials: V
authors.lastname: Zuliana
authors.forename: Marcel
authors.initials: M
authors.lastname: Hoffman
authors.forename: Henk
authors.initials: H
authors.lastname: Timmerman
authors.forename: Rob
authors.initials: R
authors.lastname: Leurs
mesh_terms: D005456:Fluorescent Dyes / Q000138:chemical synthesis*; D006146:Guanidines / Q000737:chemistry; D006801:Humans; D007457:Iodine Radioisotopes; D008024:Ligands; D010880:Piperidines / Q000737:chemistry; D011485:Protein Binding; D011869:Radioligand Assay; D011970:Receptors, Histamine H2 / Q000737:chemistry*
chemical_list: D005456:Fluorescent Dyes; D006146:Guanidines; D007457:Iodine Radioisotopes; D008024:Ligands; D010880:Piperidines; D011970:Receptors, Histamine H2; C103275:aminopotentidine