Electrochemical oxidation of inosine 5′-monophosphate in neutral aqueous solution

Electrochemical oxidation of inosine-5′-triphosphate at pyrolytic graphite electrode

“…The ribose triphosphate moieties in both the dimers seem to hydrolyze either during dimerization due to steric hindrance or during silylation at 110 • C. The second possibility can be ruled out on the basis that several purine derivatives have been found to give products having ribose unit attached during silylation [38] and addition of 0.1 M HCl to the electrolyzed sample to convert the sodium salt into the free acid would further cause the cleavage of ␤-N-glycosidic linkage as well documented in the literature [39]. Interestingly, during silylation all the reactive hydrogen atoms attached to nitrogen atoms are replaced with trimethylsilyl units to give the corresponding tetrasilylated C C dimer (16) and disilylated N N dimer (19) having m/z 558 and 414, respectively. On the other hand, the formation of C O O C bridged dimer (23) occurs due to the rapid dimerization of oxygen free radical specie (21), formed at C 8 position on 1e − , 1H + electrochemical oxidation of 2,8-dihydroxyinosine-5 -triphosphate (20).…”

“…The observed behavior is also compared with that of its parent compound inosine and its nucleotide derivative inosine-5 -monophosphate (IMP) studied previously [18,19] to study the effect of the phosphate moieties on the ease of oxidation. Analysis of the voltammetric studies clearly indicates that the difference in inosyl derivatives is expected to arise from the influence of phosphate groups on molecular size, diffusion rate, adsorptive behavior onto the electrode surface and the electron density in active sites.…”

“…The mass spectrum of its trimethylsilyl derivative exhibited a clear peak at R t ∼ 9.67 min having m/z 414 (M + , 2.97%) and suggested the material as disilylated N N bridged dimer (19) formed by the rapid dimerization of radical species (13).…”

“…The species responsible for molar masses 766, 414, 558 and 438 were due to hexasilylated C O O C (24), disilylated N N (19) and tetrasilylated C C linked (16) dimers and tetrasilylated d-ribose (11).…”

“…As inosine and its nucleotides are of great interest in study of the mutations in RNA, which probably occur via chemical changes to the bases [16], thermochemical studies on inosine and its nucleotides have also been reported [17]. The redox reactions of inosine and its nucleotides [18,19] have also been studied in an expectation to provide unique insights into their redox chemistry. However, not a single product of electrochemical oxidation of 5 -ITP has yet been characterized inspite of the fact that it is an important nucleotide involved in human system.…”