Polarographic Study of the System Alloxan-Alloxantin-Dialuric Acid

Electrolytic Oxidation of Uric Acid: Products and Mechanism*

“…While wave I of alloxan (£i/2 = -0.1 v) occurs at an unusual potential, which is therefore useful for identification, its magnitude is unusually small (ca. 0.1 of "normal" for a 2e process) (Struck and Elving, 1964b); therefore this wave can easily be overlooked in dilute solution. Reexamination of the product solution at a higher concentration showed that a wave having the same E,/, as wave I of alloxan was indeed present.…”

“…Reexamination of the product solution at a higher concentration showed that a wave having the same E,/, as wave I of alloxan was indeed present. Because of overlap with the hydrogen discharge, wave II of alloxan can be observed only above pH 4.6; above pH 6, alloxan rapidly rearranges to polarographically nonreducible alloxanic acid (Struck and Elving, 1964b). Thus wave II of the oxidation-product solution was considered to be alloxan wave II.…”

Electrochemical oxidation-reduction paths for pyrimidine, cytosine, purine and adenineCorrelation and application

“…Above pH 9, where the reduction peak is masked by background discharge, the oxidation peak is still observed vrovided that the initial scan is continued some distance bevond the backmound discharee potential.' The anodic peak appears over the whole pH range investigated (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12). Hence, the ano& peak is due to the oxidation of the reduction product or some species derived from it.…”

“…Rewriting equation (9) and neglecting the small entropy and logarithmic terms, J%,Z = i% + (SEo, -SEXed) + constant (11) Then, plots of El,, us. the LEMO energy (usually, ki expressed in units of @ should be linear, provided that for the series of compounds studied the solvation energy terms between members of the series are constant or vary in a regular fashion.…”

On the electrochemical oxidation of 5‐hydroxy barbituric acid

“…Therefore, the knowledge of the voltammetric behavior of this compound will be of particular interest. Only a few references are available on the oxidation of HB on mercury electrode [12,13]. The present investigation describes the oxidation of HB in detail in aqueous and nonaqueous media.…”