Combination of Aryl Diselenides/Hydrogen Peroxide and Carbon‐Nanotube/Rhodium Nanohybrids for Naphthol Oxidation: An Efficient Route towards Trypanocidal Quinones

Abstract

This work reports a combination of aryl diselenides/hydrogen peroxide and carbon-nanotube (CNT)/rhodium nanohybrids (RhCNT) for naphthol oxidation towards the synthesis of 1,4-naphthoquinones and evaluation of their relevant trypanocidal activity. Under a combination of (PhSe) /H O in the presence of O in iPrOH/hexane, several benzenoid (A-ring)-substituted quinones were prepared in moderate to high yields. We also studied the contribution of RhCNT as co-catalyst in this process and, in some cases, yields were improved. This method provides an efficient and versatile alternative for preparing A-ring-modified naphthoquinonoid compounds with relevant biological profile.

Structure-based identification of naphthoquinones and derivatives as novel inhibitors of main protease Mpro and papain-like protease PLpro of SARS-CoV-2

“…Compounds containing sulfur, as sulfoxides and sulfones [98,99], selenium [100], iodine [47], amines, bromine, hydroxyls, alkenes, among other substituent groups [46,[101][102][103][104][105][106][107] were studied and evaluated according to their potential to act as anti-SARS-CoV-2. Imine derivatives were also targeted in our studies and were placed in group 6 [67].…”

“…Repurposing existing chemical libraries is a promising strategy to quickly discover novel therapies [43,44]. Several newly discovered therapies for treatment of COVID-19 infection are derived from approved drugs, clinical candidates, and other pharmacologically active compounds that were originally developed for other indications [45][46][47][48]. In addition, knowledge gained from previous outbreaks of SARS, MERS, and bat coronavirus (BatCoV-RaTG13) have facilitated the rapid discovery of SARS-CoV-2 drugs [2,6,49].…”

Oxidative Dearomatization of Phenols and Polycyclic Aromatics with Hydrogen Peroxide Triggered by Heterogeneous Sulfonic Acids

“…[25] On the contrary, reports with hydrogen peroxide, [26] which is a cheaper and more benign chemical, are at present limited to the use of transition-metal based catalysts. [27,28] Notable exceptions are represented by the use of diphenyldiselenide as precursor of the mediator for the homogeneous oxidation of 1-naphthols [28] and a recent report that uses 1,1,1,3,3,3-hexafluoroisopropanol (HFIP). [29] Moreover, to the best of our knowledge a practical method for the dearomatization of simple arenes with this oxidant has not been reported yet.…”

“…Most of the reported methods use relatively strong and expensive oxidants, including hypervalent iodine reagents, [23] NBS [24] and organic peroxides [25] . On the contrary, reports with hydrogen peroxide, [26] which is a cheaper and more benign chemical, are at present limited to the use of transition‐metal based catalysts [27,28] . Notable exceptions are represented by the use of diphenyldiselenide as precursor of the mediator for the homogeneous oxidation of 1‐naphthols [28] and a recent report that uses 1,1,1,3,3,3‐hexafluoroisopropanol (HFIP) [29] .…”

Ruthenium(II)‐Catalyzed C–H Alkenylation of Quinones: Diversity‐Oriented Strategy for Trypanocidal Compounds

“…Simple modifications to the B‐ring of the quinoidal system are viable via Michael addition reactions, even in an asymmetric fashion . The modification of the benzenoid A‐ring of the 1,4‐naphthoquinone (1,4‐NQs), in contrast, involves the prior construction of the functionalized quinoidal system via oxidation reactions or extended synthetic routes with the preparation of an A‐ring‐substituted quinone via various steps . In this case, new modular strategies for direct A‐ring‐modifications are highly warranted …”