title: Tris-ureas as transmembrane anion transporters.
abstract: Nine tris-urea receptors (L(1)-L(9)) have been synthesised and shown to coordinate to a range of anionic guests both by (1)H NMR titration techniques and single crystal X-ray structural analysis. The compounds have been shown to be capable of mediating the exchange of chloride and nitrate and also chloride and bicarbonate across POPC or POPC : cholesterol 7 : 3 vesicle bilayer membranes at low transporter loadings. An interesting dependency of anion transport on the nature of the cation is evidence to suggest that a M(+)/Cl(-) cotransport process may also contribute to the release of chloride from the vesicles.
authors.affiliation: Dipartimento di Scienze Chimiche e Geologiche, Università degli Studi di Cagliari, S.S. 554 Bivio per Sestu, 09042 Monserrato (CA), Italy. ccaltagirone@unica.it.
authors.forename: Martina
authors.initials: M
authors.lastname: Olivari
authors.forename: Riccardo
authors.initials: R
authors.lastname: Montis
authors.forename: Stuart N
authors.initials: SN
authors.lastname: Berry
authors.forename: Louise E
authors.initials: LE
authors.lastname: Karagiannidis
authors.forename: Simon J
authors.initials: SJ
authors.lastname: Coles
authors.forename: Peter N
authors.initials: PN
authors.lastname: Horton
authors.forename: Lucy K
authors.initials: LK
authors.lastname: Mapp
authors.forename: Philip A
authors.initials: PA
authors.lastname: Gale
authors.forename: Claudia
authors.initials: C
authors.lastname: Caltagirone
mesh_terms: D001639:Bicarbonates / Q000737:chemistry; D002712:Chlorides / Q000737:chemistry; D002784:Cholesterol / Q000737:chemistry; D008051:Lipid Bilayers / Q000737:chemistry; D026901:Membrane Transport Proteins / Q000737:chemistry*; D009566:Nitrates / Q000737:chemistry; D010713:Phosphatidylcholines / Q000737:chemistry; D014508:Urea / Q000031:analogs & derivatives* / Q000737:chemistry*
chemical_list: D001639:Bicarbonates; D002712:Chlorides; D008051:Lipid Bilayers; D026901:Membrane Transport Proteins; D009566:Nitrates; D010713:Phosphatidylcholines; D014508:Urea; D002784:Cholesterol; C028694:1-palmitoyl-2-oleoylphosphatidylcholine