Fe(II)-培洛霉素及培洛霉素衍生物的X射线吸收光谱研究：轴向配位对铁-嘧啶反馈键合的影响

X-ray absorption spectroscopic investigation of Fe(II)-peplomycin and peplomycin derivatives: the effect of axial ligation on Fe-pyrimidine back-bonding.

作者信息

Wasinger Erik C, Zaleski Loeb, Hedman Britt, Hodgson Keith O, Solomon Edward I

机构信息

Department of Chemistry, Stanford University, Stanford, California 94305, USA.

出版信息

J Biol Inorg Chem. 2002 Jan;7(1-2):157-64. doi: 10.1007/s007750100283. Epub 2001 Aug 2.

DOI:10.1007/s007750100283

PMID:11862552

Abstract

X-ray absorption spectroscopy (XAS) is used to study ferrous complexes of a bleomycin (BLM) congener, peplomycin (PEP), and two of its derivatives, iso-peplomycin (ISO) and depyruvamide peplomycin (DP), in which potential axial ligands have been perturbed and removed, respectively. Application of extended X-ray absorption fine structure analysis shows an elongation of the short-distance component of the first coordination sphere in DP and ISO relative to PEP. The XAS pre-edge intensity concomitantly decreases with increased axial perturbation. The short-distance component of PEP is correlated to the Fe-pyrimidine bond and is related to the amount of pi-back-bonding. Thus, the XAS analysis of these complexes provides structural information relevant to their differences in O2 reactivity.

摘要

X射线吸收光谱法（XAS）用于研究博来霉素（BLM）类似物培洛霉素（PEP）及其两种衍生物异培洛霉素（ISO）和去丙酮酸酰胺培洛霉素（DP）的亚铁配合物，其中潜在的轴向配体分别受到扰动和去除。扩展X射线吸收精细结构分析的应用表明，相对于PEP，DP和ISO中第一配位层的短程组分伸长。随着轴向扰动增加，XAS预边缘强度随之降低。PEP的短程组分与铁-嘧啶键相关，并与π-反馈键的数量有关。因此，这些配合物的XAS分析提供了与其O2反应性差异相关的结构信息。