Quantum Chemical Investigation on the Antioxidant Activity of Neutral and Anionic Forms of Juglone: Metal Chelation and Its Effect on Radical Scavenging Activity

Table 2

Gas and water phases values of the O-metal and O-H bond lengths (angstrom) of the chelates obtained from the optimized geometries at DFT/B3LYP/6-31+(d,p) level.

	Juglone						Deprotonated juglone
	Gas			Water			Gas		Water
	O1-M	O2-M	O-H	O1-M	O2-M	O-H	O1-M	O2-M	O1-M	O2-M
J-Mg	1.967	1.854	0.975	2.101	1.976	0.972	1.839	1.874	1.951	1.985
J-Ca	2.386	2.180	0.973	2.664	2.431	0.971	2.152	2.205	2.331	2.394
J-Fe	1.973	1.867	0.977	2.136	1.952	0.973	1.799	1.916	1.901	1.971
J-Co	1.934	1.891	0.979	2.032	1.936	0.973	1.790	1.912	1.868	1.976
J-Ni	1.932	1.845	0.979	2.013	1.909	0.973	1.781	1.873	1.854	1.915
J-Cu	2.080	1.910	0.974	1.936	1.834	0.976	1.925	1.950	1.816	1.846
J-Cu(I)	2.087	1.918	0.970	2.123	1.942	0.971	1.888	1.914	1.921	1.939
J-Zn	1.926	1.832	0.976	2.106	1.962	0.972	1.812	1.847	1.905	1.945