Four bioactive peroxovanadium(pV) complexes bpV(ox), bpV(bipy), bpV(phen) and bpV(pic), ([VO(O_2)_2L] n-, where ligand L=oxalic acid dianion(ox), bipyridine(bipy), 1,10-phenanthroline(phen), and pyridine-2-carboxylic...Four bioactive peroxovanadium(pV) complexes bpV(ox), bpV(bipy), bpV(phen) and bpV(pic), ([VO(O_2)_2L] n-, where ligand L=oxalic acid dianion(ox), bipyridine(bipy), 1,10-phenanthroline(phen), and pyridine-2-carboxylic acid(pic), were synthesized and characterized by 51V NMR, 1H NMR, 13C NMR, ESI-MS, IR and elemental analysis. All 1H and 13C peaks were assigned by 2D 1H-1H COSY, HMQC and HMBC. Their stereochemical structures in solution were discussed according to the NMR signals of organic ligands. The descending stability order of complexes in aqueous solution determined by 51V NMR is bpV(phen), bpV(bipy), bpV(pic) and pV(ox). The predominant decomposition patterns of these complexes were proposed on the basis of electrospray ionization MS (ESI-MS) and 51V NMR. This work will facilitate the studies of interactions between pV complexes and target biomolecules in solution so as to clarify structure-function relationship of these bioactive complexes.展开更多
Multi-nuclear NMR and ESI-MS have been applied to study the interactions between oxalato-oxodiperoxovanadate and histidine in neutral solution. Coordination between the complex and histidine was monitored by V-51 NMR....Multi-nuclear NMR and ESI-MS have been applied to study the interactions between oxalato-oxodiperoxovanadate and histidine in neutral solution. Coordination between the complex and histidine was monitored by V-51 NMR. A pair of new isomers produced via vanadium atom binding separately to N1 and N3 of the imidazole ring of histidine was characterized by several spectroscopic methods. Experimental results show that the structure activity relationship of peroxovanadium complexes bearing organic ligands may be related to the specific recognition between peroxovanadium and histidine residue of tyrosine phosphatase.展开更多
文摘Four bioactive peroxovanadium(pV) complexes bpV(ox), bpV(bipy), bpV(phen) and bpV(pic), ([VO(O_2)_2L] n-, where ligand L=oxalic acid dianion(ox), bipyridine(bipy), 1,10-phenanthroline(phen), and pyridine-2-carboxylic acid(pic), were synthesized and characterized by 51V NMR, 1H NMR, 13C NMR, ESI-MS, IR and elemental analysis. All 1H and 13C peaks were assigned by 2D 1H-1H COSY, HMQC and HMBC. Their stereochemical structures in solution were discussed according to the NMR signals of organic ligands. The descending stability order of complexes in aqueous solution determined by 51V NMR is bpV(phen), bpV(bipy), bpV(pic) and pV(ox). The predominant decomposition patterns of these complexes were proposed on the basis of electrospray ionization MS (ESI-MS) and 51V NMR. This work will facilitate the studies of interactions between pV complexes and target biomolecules in solution so as to clarify structure-function relationship of these bioactive complexes.
文摘Multi-nuclear NMR and ESI-MS have been applied to study the interactions between oxalato-oxodiperoxovanadate and histidine in neutral solution. Coordination between the complex and histidine was monitored by V-51 NMR. A pair of new isomers produced via vanadium atom binding separately to N1 and N3 of the imidazole ring of histidine was characterized by several spectroscopic methods. Experimental results show that the structure activity relationship of peroxovanadium complexes bearing organic ligands may be related to the specific recognition between peroxovanadium and histidine residue of tyrosine phosphatase.