131973-85-8Relevant academic research and scientific papers
Bismercaptoethanediazacyclooctane as a N2S2 chelating agent and Cys-X-Cys mimic for Fe(NO) and Fe(NO)2
Chiang, Chao-Yi,Miller, Matthew L.,Reibenspies, Joseph H.,Darensbourg, Marcetta Y.
, p. 10867 - 10874 (2004)
The N-protonated bismercaptoethanediazacyclooctane serves as a bidentate dithiolate ligand to oxidized Fe(NO)2 of Enemark-Feltam notation, E-F {Fe(NO)2},9 mimicking Cys-X-Cys binding of Fe(NO) 2 to proteins or thio-biomolecules. The neutral compound is characterized by the well-known g = 2.03 EPR signal which is a hallmark of dinitrosyl iron complexes, DNIC's. The Fe(NO)2 unit can be removed from the chelate by excess PhS-, producing (PhS)2Fe(NO) 2-. Transfer of NO from Fe(H+bme-daco)(NO) 2 (ν(NO) = 1740, 1696 cm-1) to FeII of [(bme-daco)Fe]2 yields the five-coordinate, square-pyramidal N 2S2-Fe(NO) (ν(NO) = 1649 cm-1), where NO is in the apical position. Its isotropic EPR signal at g = 2.05 is consistent with E-F {Fe(NO)}7 formulation. In excess NO, Roussin's red ester-type molecules are formed as dinuclear or tetranuclear species, {(μ-SRS)[Fe 2(NO)4]}n (n = 1,2). These well-characterized molecules furnish reference points for positions and patterns in ν(NO) vibrational spectroscopy expected to be useful for in vivo studies of NO degradation of iron-sulfur clusters in ferredoxins.
