The Influence of the Amide Linkage in the Fe-III-Binding Properties of Catechol-Modified Rosamine Derivatives

• Type: Article in International Scientific Journal
• Date: 2015

Authors

Queiros, C (Author) Other; Leite, A (Author) Other; Couto, MGM (Author) Other; Cunha Silva, L (Author) FCUP; Barone, G (Author) Other; de Castro, B (Author) FCUP; Maria Rangel (Author) ICBAS; Silva, AMN (Author) Other; Silva, AMG (Author) Other

Journal

Title: Chemistry - A European Journal

Vol. 21

Pages: 15692-15704

ISSN: 0947-6539

Publisher: Wiley-Blackwell

Indexing

ISI Web of Knowledge - 8 Citations

Scopus - 8 Citations

Other information

Authenticus ID: P-00G-TBJ

DOI: 10.1002/chem.201502093

Abstract (EN): The two new fluorescent ligands RosCat1 and RosCat2 contain catechol receptors connected to rosamine platforms through an amide linkage and were synthesized by using microwave-assisted coupling reactions of carboxyl- or amine-substituted rosamines with the corresponding catechol units and subsequent deprotection. RosCat1 possesses a reverse amide, whereas RosCat2 has the usual oriented amide bond (HNCO vs. CONH, respectively). The ligands were characterized by means of NMR spectroscopy, mass-spectrometry, and DFT calculations and X-ray crystallography studies for RosCat1. The influence of the amide linkage on the photophysical properties of the fluorescent ligands was assessed in different solvents and showed a higher fluorescence quantum yield for RosCat1. The coordination chemistry of these ligands with a Fe-III center has been rationalized by mass-spectrometric analysis and semiempirical calculations. Octahedral Fe-III complexes were obtained by the chelation of three RosCat1 or RosCat2 ligands. Interestingly, the unconventional amide connectivity in RosCat1 imposes the formation of an eight-membered ring on the chelate complex through a salicylate-type mode of coordination.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 13