Tautomeric and conformational switching in a new versatile N-rich heterocyclic ligand(11 views visite) Parisi E, Capasso D, Capobianco A, Peluso A, Di Gaetano S, Fusco S, Manfredi C, Mozzillo R, Pinto G, Centore R
Dalton Trans (ISSN: 1477-9226linking), 2020 Oct 27; 49(41): 14452-14462.
Keywords Parole chiave: Not available. Non disponibili.
Affiliations Affiliazioni: *** IBB - CNR ***
Department of Chemical Sciences, University of Naples Federico II, Via Cintia, I-80126 Naples, Italy. roberto.centore@unina.it.
CESTEV, University of Naples Federico II, Via De Amicis 95, 80145 Naples, Italy.
CNR-Institute of Biostructures and Bioimaging, Via Mezzocannone 16, 80134 Naples, Italy.
References Riferimenti: Not available. Non disponibili.
Tautomeric and conformational switching in a new versatile N-rich heterocyclic ligand
A new N-rich triazolo-triazole derivative, 4-methyl-7-(pyrazin-2-yl)-2H-[1,2,4]triazolo[3,2-c][1,2,4]triazole (C8H7N7), bearing a pyrazine residue at 7-position of the triazolo-triazole bicycle, was synthesized, and its acid-base and metal coordination properties were evaluated in solution. The results showed amphoteric behavior and the formation of stable complexes with Cu(ii) and Zn(ii) in pH intervals in which the ligand is neutral or deprotonated. Computational studies were performed in order to evaluate the stability of the different tautomers/conformers of the ligand, and the proton position in the neutral and acidic forms. Single crystal X-ray analysis of the free neutral ligand (2H/s-trans tautomer/conformer), and of its singly protonated (2H-3H/s-trans), doubly protonated (2H-3H-7H/s-trans) and deprotonated forms showed that the influence of the pyrazine ring on the triazolo-triazole system is mainly as electron withdrawing and chelating group, and proton acceptor. Different coordination modes have been evidenced for the neutral and deprotonated ligand. Upon metal coordination, the neutral ligand switches from 2H/s-trans to 3H/s-cis tautomer/conformer forming five-membered chelate rings, while the anionic deprotonated ligand forms six-membered chelate rings in the s-trans conformation. Altogether, five different tautomers/conformers of the ligand were isolated and characterized. In vitro tests confirmed the general antiproliferative activity of triazolo-triazole compounds and the importance of substitution in position 7 for their selectivity.
Tautomeric and conformational switching in a new versatile N-rich heterocyclic ligand
Aloj L, Aurilio M, Rinaldi V, D'Ambrosio L, Tesauro D, Peitl PK, Maina T, Mansi R, Von Guggenberg E, Joosten L, Sosabowski JK, Breeman WA, De Blois E, Koelewijn S, Melis M, Waser B, Beetschen K, Reubi JC, De Jong M * The EEE project(387 visite) Proc Int Cosm Ray Conf Icrc Universidad Nacional Autonoma De Mexico, 2007; 5(HEPART2): 977-980. Impact Factor:0 DettagliEsporta in BibTeXEsporta in EndNote
330 Records (309 escludendo Abstract e Conferenze). Impact factor totale: 1186.112 (1131.216 escludendo Abstract e Conferenze). Impact factor a 5 anni totale: 1246.93 (1186.546 escludendo Abstract e Conferenze).
Last modified by Ultima modifica di Gennaro Angrisano on in data Thursday 14 January 2021, 14:47:49 11 views visite. Last view on Ultima visita in data Monday 01 February 2021, 17:12:29