title: Coordination features of difunctionalized beta-cyclodextrins with carnosine: ESI-MS and spectroscopic investigations on 6A,6D-di-(beta-alanyl-L-histidine)-6A,6D-dideoxy-beta-cyclodextrin and 6A,6C-di-(beta-alanyl-L-histidine)-6A,6C-dideoxy-beta-cyclodextrin and their copper(II) complexes.
abstract: The synthesis and characterization of two beta-cyclodextrins (beta-CD) functionalized with two units of carnosine (beta-alanyl-L-histidine) through the amino group, 6A,6C-(beta-alanyl-L-histidine)-6A,6C-dideoxy-beta-cyclodextrin (ACCDAH) and 6A,6D-(beta-alanyl-L-histidine)-6A,6D-dideoxy-beta-cyclodextrin (ADCDAH), are reported. NMR and C.D. data of the ligands indicate a different interaction of dipeptide chains with upper rim and cavity of beta-CD. Analogously, spectroscopic and electrospray ionization mass spectrometry data show different copper(II) complex species formed by the two regioisomers. The ability of carnosine-cyclodextrin derivatives to bind copper ions in a head-to-tail fashion induces the formation of oligomeric species (up to hexamers) in the case of ACCDAH, where the two carnosine moieties are adjacent, while in the ADCDAH case the mutual interaction between the peptidic chains of two ADCDAH molecules allows the almost exclusive formation of a copper-assisted self-assembled dimeric species.
authors.affiliation: Istituto di Chimica e Tecnologia dei Polimeri, CNR-Sezione di Catania, Catania, Viale A. Doria, 6, Catania 95125, Italy.
authors.forename: Placido
authors.initials: P
authors.lastname: Mineo
authors.forename: Daniele
authors.initials: D
authors.lastname: Vitalini
authors.forename: Diego
authors.initials: D
authors.lastname: La Mendola
authors.forename: Enrico
authors.initials: E
authors.lastname: Rizzarelli
authors.forename: Emilio
authors.initials: E
authors.lastname: Scamporrino
authors.forename: Graziella
authors.initials: G
authors.lastname: Vecchio
mesh_terms: D002336:Carnosine / Q000737:chemistry* / Q000378:metabolism; D003300:Copper / Q000737:chemistry* / Q000378:metabolism; D003505:Cyclodextrins / Q000138:chemical synthesis / Q000737:chemistry* / Q000378:metabolism; D004151:Dipeptides / Q000737:chemistry / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D021241:Spectrometry, Mass, Electrospray Ionization; D047392:beta-Cyclodextrins
chemical_list: D003505:Cyclodextrins; D004151:Dipeptides; D047392:beta-Cyclodextrins; C061116:alanylhistidine; D003300:Copper; D002336:Carnosine; C031215:betadex