Electrochemical studies of biologically-significant pterin compounds

Redox mechanism of lumazine at a glassy carbon electrode

“…The reduction of LMZ, reduction peak 2 c , involves two electrons and two protons and is attributed to the reduction of the pteridine ring to yield the dihydro derivative (3). The formation of such a product has also been reported in the literature [22][23][24]. The appearance of the anodic peaks 3 a and 4 a in the reverse scan corresponds to the two step oxidation of LMZ derivative (3), the product of LMZ reduction formed at the GCE surface, to generate compounds (4) and (5), Scheme 2B.…”

“…The reduction of pteridine derivatives was investigated using the DME [22] and the Pt disk electrode [23]. Concerning LMZ, its electrochemical reduction was studied using a HMDE for its trace determination [24]. However, as the use of HMDE is limited to the negative potential range, the information obtained allowed conclusions only about the reduction of LMZ.…”

An extensive study of electrochemical behavior of brimonidine and its determination at glassy carbon electrode

“…According to the postulated reduction mechanism of quinoxaline core present in the molecule of varenicline [10], it can be assumed that similar reversible reduction of BRIM happens at the pyrazine ring of quinoxaline moiety, forming a dihydro-derivative, as in the case of other compounds containing the pyrazine ring [17][18][19][20][21]. The proposed mechanism is presented in the Scheme 1A.…”

Evaluation of kinetic parameters and redox mechanism of quinoxaline at glassy carbon electrode

“…According to the postulated reduction mechanism of varenicline [25], and brimonidine [10] at GCE it can be assumed that similar reversible reduction of QUI happens at the pyrazine ring moiety, forming a dihydro-derivative, as in the case of other compounds containing the pyrazine ring [26][27][28][29][30]. The proposed mechanism is presented in the Scheme 1.…”