title: Bifunctional fluorescent calix[4]arene chemosensor for both a cation and an anion.
abstract: [reaction: see text] A new fluorogenic cone calix[4]triazacrown-5 (1) bearing two pyrene amide groups and its structural analogue 2 have been prepared. Excited at 343 nm, 1 and 2 reveal excimer emissions at 448 and 472 nm, respectively. When heavy metal ions such as Pb(2+) and Co(2+) are bound to 1, the fluorescence intensities of both monomer and excimer are quenched whereas H bonding-assisted F(-) binding to 1 gives rise to a quenched monomer emission with little excimer emission change.
authors.affiliation: Department of Chemistry, Institute of Nanosensor and Biotechnology, Dankook University, Seoul 140-714, Korea.
authors.forename: Ji Yeon
authors.initials: JY
authors.lastname: Lee
authors.forename: Sung Kuk
authors.initials: SK
authors.lastname: Kim
authors.forename: Jong Hwa
authors.initials: JH
authors.lastname: Jung
authors.forename: Jong Seung
authors.initials: JS
authors.lastname: Kim