Li Z W, Taube H
Department of Chemistry, Stanford University, CA 94305.
Science. 1992 Apr 10;256(5054):210-3. doi: 10.1126/science.1348872.
A new recognition probe for biomolecules, [en2Os(eta 2-H2)]2+ (1; en, ethylenediamine), is reported. In aqueous solution, 1 binds readily to a variety of biomolecules, including nucleotides, RNA, amino acids, peptides, and phospholipids. In each case, binding leads to a characteristic proton nuclear magnetic resonance (1H NMR) for the dihydrogen that appears in a spectral window in the range delta = 0 to -20 parts per million, and as well to characteristic values of the coupling JHD and of the relaxation time T1. Small structural differences in molecules such as DGMP (2'-deoxyguanosine 5'-monophosphate) and IMP (inosine 5'-monophosphate) or Asp and Glu can readily be distinguished, such as when 1 binds to the N-7 position of the nucleobase of DGMP or IMP and when 1 binds to the carboxylate of Asp or Glu. Upon one-electron oxidation of the metal center, diamagnetic 1 is converted to a paramagnetic probe.
报道了一种用于生物分子的新型识别探针[en2Os(η2-H2)]2+(1；en，乙二胺)。在水溶液中，1能与多种生物分子迅速结合，包括核苷酸、RNA、氨基酸、肽和磷脂。在每种情况下，结合都会导致出现在δ=0至百万分之-20范围内光谱窗口中的二氢产生特征性的质子核磁共振(1H NMR)，以及耦合JHD和弛豫时间T1的特征值。分子中的微小结构差异，如DGMP(2'-脱氧鸟苷5'-单磷酸)和IMP(肌苷5'-单磷酸)或天冬氨酸和谷氨酸，很容易区分，例如当1与DGMP或IMP的核苷酸碱基的N-7位结合时，以及当1与天冬氨酸或谷氨酸的羧酸盐结合时。金属中心经单电子氧化后，抗磁性的1转化为顺磁性探针。
