How does the pH influences the Ru-NO coordination compounds?

Author(s)

Orenha, Renato P. ^[1] ; Galembeck, Sergio E. ^[1]

Affiliation

^[1] Univ Sao Paulo, Fac Filosofia Ciencias & Letras Ribeirao Preto, Dept Quim, Ribeirao Preto - Brazil

• Document type: Journal article
• Source: International Journal of Quantum Chemistry; v. 119, n. 20 OCT 15 2019.
• Web of Science Citations: 0

Abstract

The pH influence has important role in the bioavailability of coordination compounds. fac-{[}Ru(NO)Cl-2(kappa N-3(4),N-8,N-11{[}1-carboxypropyl]cyclam)](+), 1, and the species found at different pHs, 2-4, were investigated. One series of computational methodologies has been used to investigate these compounds. One special highlight is to interacting quantum atoms method, where the total interaction energy, EintAB, between two atoms has been used as base to estimate the chemical bonds strength. The deprotonation of -CO2H, 12 (pK(a) = 3.3), creates a hydrogen bond in the complex 2, N(3)-HMIDLINE HORIZONTAL ELLIPSIS center dot OCO-, with a more favorable EintAB than the presents in 1, N(3)-HMIDLINE HORIZONTAL ELLIPSIS center dot OCOH. There are no changes in EintAB in Ru-NO bond. The second deprotonation occurs in the N(2) atom of the cyclam group, 23 (pK(a) = 8.0). It promotes an increase in the covalent character of Ru-N(2). In contrast, there is no changes in Ru-N(5)O bond. For higher pHs, there is a 34 equilibrium (pK(a) = 11.5) and the conversion of Ru-N(5)O for Ru-N(5)O-2. The Ru-N(5) of 4 shows a larger ionic character than 3. Thus, Ru-NO in 1-4 has worthy stability about a large pH range, showing potential application as NO scavengers. (AU)

• FAPESP's process: 14/50265-3 - Distribution and metabolism of natural and synthetic xenobiotics: from the comprehension of reactional process to tissue imaging generation
• Grantee: Norberto Peporine Lopes
• Support Opportunities: BIOTA-FAPESP Program - Thematic Grants
• FAPESP's process: 15/15176-2 - How to tune the Ru-NO coordination bond: insight from Kohn-Sham molecular orbital theory and energy decomposition analyses
• Grantee: Renato Pereira Orenha
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate (Direct)
• FAPESP's process: 11/20351-7 - Computational study of ruthenium-nitosyl compounds
• Grantee: Renato Pereira Orenha
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• FAPESP's process: 08/02677-0 - Computational Study of the interaction between HIV-1 reverse transcriptase non-nucleoside inhibitors with amino acids of the inhibitory site
• Grantee: Sergio Emanuel Galembeck
• Support Opportunities: Regular Research Grants