One- and two-electron reduction of hydroxy-1,4-naphthoquinones and hydroxy-9,10-anthraquinones

Electrochemical and ESR study on the transformation processes of α-hydroxy-quinones

“…The presence of this type of hydroxy functionality seems to be related to the biological activity of this kind of compound [2][3][4][5][6][7], and the position of this functional group can alter the typical redox behavior of the quinoid moiety [8][9][10][11][12]. This is relevant, considering that most of the biological activity of quinonoid systems is related to their capacity to carry out free radical generation via redox reactions.…”

Hydrogen bonding effects on the association processes between chloranil and a series of amides

“…Amide and quinone functional groups, play key roles in many biological systems, where hydrogen bonding is of particular importance. It has been recognised that quinones participate as electron carriers in the oxidative phosphorylation process [14][15][16] and can be used as vitamins or drugs [17,18]. They can also develop specific biochemical functions such as cytotoxicity and antineoplastic activity [19][20][21][22].…”

pH- and temperature-responsive redox behavior of hydroxyanthracenediones

“…Though anthracenediones have a broad spectrum of applications and their reduction is widely studied [17][18][19][20][21][22][23][24], the literature about their electro-oxidation is limited and thus deserves further investigations. In the present work, we focus on the pH-dependent and temperature-dependent electro-oxidation of 4,8-dihydroxy-9,10-dioxo-9,10-dihydroanthracen-1-yl acetate (HACAD), 1,4,5-trihydroxyanthracene-9,10-dione (HAD) and 1,4,5-trihydroxy-2-methyl-3-(3-oxobutyl)anthracene-9,10-dione (HOAD), with the hope of providing useful insights into their electron transfer reactions.…”

“…The quinones and anthracenediones undergo two successive one-electron reduction steps to produce the corresponding semiquinone and dianion, generating two separate cathodic waves in which the first step is fully electrochemically reversible and the second step is either reversible or quasi-reversible, depending on the experimental conditions [17][18][19][20][21]. Anthracenediones containing hydroxyl groups are interesting from an electrochemical point of view, and their position alters the redox behavior of the quinonoid moiety [18,[22][23][24] due to the formation of intramolecular hydrogen bonds. In addition, these moieties are related to the biological activity of ACDs [25,26].…”