The Synthesis, Crystal Structure, EPR, UV, NMR And Properties Study Of Molybdenum And Tungsten Complexes

As a sort of trace life element, the functions of molybdenum are shown through the activities of its enzymes. The anticancer or antitumor properties of some molybdo-compounds are discovered also recently. The activities of Mo-cofactor in molybdo-enzyme will be reduced if molybdenum is replaced by tungsten though tungsten is the analogous element to molybdenum and found as some kinds of tungsto-enzymes in which the coordination structure of W-cofactor is similar to that of Mo-cofactor of molybdo-enzyme in biological system. Polyoxomolybdenum and polyoxotungsten organo-derivatives can be used to study the catalysis mechanism of the polymolybdate and polytungstate anions which are very important in catalysis industry. Herein the main research works in the above fields of a doctoral graduate are outlined as follows:1. Biomimetic synthesis, anticancer and antitumor of chiral octahedral molybdenum and tungsten complexes studied by EPR, UV and NMR· Ten types of chiral octahedral molybdenum and tungsten complex anions coordinated with catachol [MO₂(OC₆H₄O)₂]^n- [M = Mo(V), W(VI), and Mo(V) mixed with W(VI); n = 2, 3] were synthesized in the mixed solvent of CH₃OH and CH₃CN which the pH was adjusted to 9 using Ethylenediamine, 1,2-Diaminopropane and 1,3-Diaminopropane respectively and their crystal structures were determined by X-ray diffraction. Their counter ions are protonated Ethylenediamine, protonated 1,2-Diaminopropane and protonated 1,3-Diaminopropane.· The similar EPR spectra shown by the complex 1, 2,10 and flavoenzyme suggests that the complexes and flavoenzyme have related coordination structure feature. The similarity of the UV spectra shown by complex 2 and oxidized xanshine oxidase from milk and xanshine dehydrogenese from chicken liver suggests that the three kinds of substances might have the same electronic configuration in the central metal cation.· Regarding the results of the studies of ¹H NMR,¹³C NMR, ³¹P NMR and ¹⁵N NMR of these complexes before and after ATP is added, we can conclude that: â‘  Mo and W ions in these complexes do not coordinate directly to the N atoms of base...