Review of the effects of pH on the synthesis of heteropoly tungstate anions.
The reaction of the WO4(2-) ion in the pH range 2 to 8 was carried out with the following metal ions individually in combination: Mn2+, Mn3+, Fe2+, Fe3+, Co2+, Co3+, Ni2+, Cu1+, Cu2+, Zn2+, Ga3+, Mg2+, In3+, RAsO3(2-), RSbO3(2-). Some 36 heteropolyanions have been isolated in the crystalline form characterized fully. The antiviral activity of these anions has been determined against HIV, herpes respiratory viruses. The redox potentials for these anions have been measured by cyclic voltammetry documented. At pH 8, the anions adopt a Weakley structure at pH 7, the Keggin structure is formed. At pH 6 to 7, the distorted Keggin structure, 1:1:11, is formed. Below pH 6, the distorted Dawson structure is formed. Some anions showed good antiviral activity with positive redox potentials and others with negative redox potentials. When the metal ion is attached to an organic group, a ring-type structure is formed: a 2:5, 2:6, and 1:7 heteropolytungstate.
Wasfi
Sadiq H
SH
Chemistry Department, Delaware State University, Dover, Delaware 19901, USA. swasfi@dsc.edu
Johnson
W Leo
WL
D019380:Anti-HIV Agents / Q000138:chemical synthesis / Q000494:pharmacology; D006678:HIV / Q000187:drug effects; D006863:Hydrogen-Ion Concentration; D010084:Oxidation-Reduction; D000071228:Polyelectrolytes; D011108:Polymers / Q000138:chemical synthesis*; D018139:Simplexvirus / Q000187:drug effects; D017973:Tungsten Compounds / Q000138:chemical synthesis*
D019380:Anti-HIV Agents; D000071228:Polyelectrolytes; D011108:Polymers; D017973:Tungsten Compounds; C045951:tungstate