@article {509,
	title = {Synthesis and solution studies of the complexes of pyrone analogue ligands with vanadium(IV) and vanadium(V)},
	journal = {Inorganica Chimica Acta},
	volume = {339},
	year = {2002},
	note = {ISI Document Delivery No.: 616BDTimes Cited: 8Cited Reference Count: 16},
	month = {Nov},
	pages = {393-399},
	type = {Article},
	abstract = {A new potentially tetradentate chelator N,N{\textquoteright}-bis(3-hydroxy-6-methyl-2-methylene-4-pyrone)ethylenediamine (H-2(en(ama)(2))), has been synthesized and its protonation constants, as well as those of two other 3-hydroxy-4-pyrone ligands (allomaltol (Hama) and methylmaltol (Hmma)) determined potentiometrically at 25 degreesC and 0.16 M NaCl: pK(a1) = 3.67+/-0.07, pK(a2) = 5.82+/-0.07, pK(a3) = 7.96+/-0.04, pK(a4) = 8.77+/-0.03 for [H-4(en(ama)(2))](2+), pK(a) = 8.04+/-0.02 for Hama and pK(a) = 8.82+/-0.02 for Hmma. Potentiometric pH titrations were also used to measure the stability constants of these ligands with V(IV) and V(V) and to study the structures of the complexes of (en(ama)(2))(2-) in aqueous solution. H-1 NMR was used to assign the protonation constant values to the different protons in H-2(en(ama)(2)). A pM versus pH plot confirmed that H-2(en(ama)(2)) has much stronger complexation than its bidentate analogues, in the same pH range. (C) 2002 Elsevier Science B.V. All rights reserved.},
	keywords = {AQUEOUS-SOLUTION, BIS(MALTOLATO)OXOVANADIUM(IV), GLUCOSE, insulin drugs, ION-COORDINATING PROPERTIES, potentiometry, stability constants, vanadium complexes},
	isbn = {0020-1693},
	url = {<Go to ISI>://000179281100048},
	author = {Song, B. and Saatchi, K. and Rawji, G. H. and Orvig, Chris}
}
@article {5201,
	title = {Proton- and lanthanide-coordinating properties of the tetraaza macrocycle (EDDA-KA)(2) in aqueous solution},
	journal = {Canadian Journal of Chemistry-Revue Canadienne De Chimie},
	volume = {79},
	number = {5-6},
	year = {2001},
	note = {ISI Document Delivery No.: 456EVTimes Cited: 4Cited Reference Count: 36},
	month = {May},
	pages = {1058-1067},
	type = {Article},
	abstract = {{The new potentially multidentate ligand (EDDA-KA)(2) has been prepared and its acid-base properties determined. Its coordination properties with three lanthanide ions (La3+, Gd3+, and Lu3+) and Fe3+ have been studied in aqueous solution (I = 0.16 M NaCl, 25degreesC) by potentiometric pH, spectrophotometric, and H-1 NMR titrations. In total, eight pK(a) values could be determined by these diverse methods. From the H-1 NMR titrations, all the deprotonation steps could be determined and assigned (in groups). Strong hydrogen bonding among two nitrogen atoms and one oxygen atom on the pyrone ring was observed, and the corresponding pK(a) values were estimated to be 13.2 and 14.0. By comparison with similar systems, an equilibrium constant for the formation of the hydrogen bond was estimated},
	keywords = {ACID-BASE, acidity constants, ALKALINE-EARTH, amino, BINDING-PROPERTIES, carboxylate chelator, CHEMISTRY, CONTRAST AGENTS, DERIVATIVES, DYNAMICS, Fe3+, GADOLINIUM, Gd3+, La3+, Lu3+, METAL-COMPLEXES, STABILITIES, stability constants},
	isbn = {0008-4042},
	url = {<Go to ISI>://000170070900078},
	author = {Song, B. and Kurokawa, G. S. and Liu, S. and Orvig, Chris}
}
