E-Locus - Institutional Repository of the University of Crete - Synthetic, Spectroscopic, structural, and speciation studies in the Co(II) - N,N

Home Synthetic, Spectroscopic, structural, and speciation studies in the Co(II) - N,N - Bis(phosponomethyl)glycine system

Results - Details

[Add to Basket]

Identifier

000040089

Title

Synthetic, Spectroscopic, structural, and speciation studies in the Co(II) - N,N - Bis(phosponomethyl)glycine system

Author

Mateescu, Anca Constantin

Thesis advisor

Κουτσολέλος, Αθανάσιος
Σαλίφογλου, Αθανάσιος

Abstract

Cobalt plays important roles in biological systems, despite its low availability in the earth's crust. The most common examples are vitamin B12 and coenzyme B12, a cofactor required for a group of enzymatic systems of central importance in biochemistry. Its involvement in (bio)chemical processes contributing to the integrity of the physiology of humans underscores its ability to promote (bio)chemistry with molecular targets of variable mass and biological properties. Given the fact that organic phosphonates are widespread substrates-ligands in biological fluids, we sought to investigate the relevant chemistry with Co(II). In an effort to unravel the aqueous chemistry of Co(II) in the presence of phosphonate ligands, two new Co(II)- N,N-bis(phosphonomethyl) glycine acid, aqueous soluble, complexes were synthesized, isolated and characterized. Aqueous reactions of Co(NO3)2 . 6H2O with N,N-bis(phosphonomethyl) glycine acid led to the isolation of complex [Co(C4H9O8NP2)2(H2O)2] . 2H2O (1) at low pH. At higher pH values 5.5-6 aqueous reactions of Co(CH3COO)2 . 6H2O with N,N-bis(phosphonomethyl) glycine acid in the presence of ammonia led to the isolation of complex (NH4)4[Co(H2O)6][Co{N(CH2COO)(CH2PO3)2}(H2O)2]2[Co(H2O)2{N(CH2COO)(CH2PO3 H)(CH2PO3)}Co(NH3)2(H2O)3]2 .10 H2O . 1.36 CH3CH2OH (2). The complexes were further characterized analytically, spectroscopicaly (FTIR, UV-vis, EPR), and electrochemically (cyclic voltammetry). Speciation studies were carried out for nitrilotriacetic acid (NTA) and its phosphonic derivatives (N-(phosphonomethyl)- iminodiacetic acid (NTAP), N,N-bis(phosphonomethyl)glycine (NTA2P) and nitrilotris( methylphosphonic acid) (NTA3P)). Such information are vital in trying to understand the interactions of soluble and bioavailable forms of Co(II) in biological interactions in human organisms.

Language

Greek

Subject

Cobalt

Cobalt complexes

N,N-Bis(phosponomethyl)glycine

Speciation studies

Structural studies

Issue date

2004-11-01

Collection

School/Department--School of Sciences and Engineering--Department of Chemistry--Post-graduate theses