title: A fluorescent sensor for 2,3-bisphosphoglycerate using a europium tetra-N-oxide bis-bipyridine complex for both binding and signaling purposes.
abstract: Host 1 was designed and synthesized as a fluorescent sensor for 2,3-bisphosphoglycerate (BPG, 3). The design features a tris-functionalized triethylbenzene core to preorganize binding groups. The three cationic moieties, a tetra-N-oxide bipyridine-europium complex and two ammonium groups, were included to complement the three anionic functionalities on the guest. Beyond acting as a binding site, the europium complex was used to signal binding of the guest through modification of the charge transfer emission. A 1:1 complex with BPG was determined in 50 % methanol/acetonitrile with a K(a) of 6.7 x 10(5) mol(-1) by monitoring the reduction of the fluorescence signal upon guest addition. In the titration of related glycolytic intermediates lacking a second phosphate (4-6) into host 1, 2:1 host to guest binding was observed. Similarly, control compound 2, which lacks the ammonium groups, binds BPG and 4-6 in a 2:1 fashion. Also, phenylphosphate 7 binds to host 1 in a 1:1 stoichiometry with a K(a) over three times less than 3.
authors.affiliation: The University of Texas at Austin Austin, TX 78712-1167, USA.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Best
authors.forename: Eric V
authors.initials: EV
authors.lastname: Anslyn
mesh_terms: D015082:2,2'-Dipyridyl / Q000031:analogs & derivatives / Q000032:analysis / Q000737:chemistry* / Q000378:metabolism; D019794:2,3-Diphosphoglycerate / Q000032:analysis*; D015374:Biosensing Techniques / Q000379:methods*; D002625:Chemistry, Organic / Q000379:methods; D005063:Europium / Q000737:chemistry; D005453:Fluorescence; D005456:Fluorescent Dyes / Q000032:analysis / Q000737:chemistry / Q000378:metabolism; D009942:Organometallic Compounds / Q000032:analysis / Q000737:chemistry* / Q000378:metabolism; D010777:Photochemistry / Q000379:methods; D000644:Quaternary Ammonium Compounds; D015398:Signal Transduction; D017186:Titrimetry
chemical_list: C471564:1-((3-(N,N-bis(6-(2,2'-bipyridyl-1,1'-dioxide)methyl)carbamoyl)propamoyl)aminomethyl)-3,5-bis(aminomethyl)-2,4,6-triethylbenzene bis(acetic acid) europium(III) trisacetate; D005456:Fluorescent Dyes; D009942:Organometallic Compounds; D000644:Quaternary Ammonium Compounds; D019794:2,3-Diphosphoglycerate; D005063:Europium; D015082:2,2'-Dipyridyl