An electrochemical study on the redox chemistry of cyclic benzimidazole derivatives with potent anticancer activity

Mechanistic Aspects of the Electrochemical Oxidation of Aliphatic Amines and Aniline Derivatives

The electrochemical oxidation of amines is an essential alternative to the conventional chemical transformation that provides critical routes for synthesising and modifying a wide range of chemically useful molecules, including pharmaceuticals and agrochemicals. As a result, the anodic reactivity of these compounds has been extensively researched over the past seven decades. However, the different mechanistic aspects of the electrochemical oxidation of amines have never been discussed from a comprehensive and general point of view. This review examines the oxidation mechanism of aliphatic amines, amides, aniline and aniline derivatives, carbamates, and lactams, either directly oxidised at different electrode surfaces or indirectly oxidised by a reversible redox molecule, in which the reactive form was generated in situ. The mechanisms are compared and simplified to understand all possible pathways for the oxidation of amines using only a few general mechanisms. Examples of the application of these oxidation reactions are also provided.

Simple inorganic base promoted polycyclic construction using mucohalic acid as a C3 synthon: synthesis and AIE probe application of benzo[4,5]imidazo[1,2-a]pyridines

Using mucohalic acid as C3 synthon via a transition metal-free multicomponent reaction, an eco-friendly protocol to synthesize C1-functionalized benzo[4,5]imidazo[1,2-a]pyridines which can be applied as fluorescence probe for picric acid is described.

Modeling the Antileukemia Activity of Ellipticine-Related Compounds: QSAR and Molecular Docking Study

The antileukemia cancer activity of organic compounds analogous to ellipticine representes a critical endpoint in the understanding of this dramatic disease. A molecular modeling simulation on a dataset of 23 compounds, all of which comply with Lipinski's rules and have a structure analogous to ellipticine, was performed using the quantitative structure activity relationship (QSAR) technique, followed by a detailed docking study on three different proteins significantly involved in this disease (PDB IDs: SYK, PI3K and BTK). As a result, a model with only four descriptors (HOMO, softness, AC1RABAMBID, and TS1KFABMID) was found to be robust enough for prediction of the antileukemia activity of the compounds studied in this work, with an R² of 0.899 and Q² of 0.730. A favorable interaction between the compounds and their target proteins was found in all cases; in particular, compounds 9 and 22 showed high activity and binding free energy values of around -10 kcal/mol. Theses compounds were evaluated in detail based on their molecular structure, and some modifications are suggested herein to enhance their biological activity. In particular, compounds 22_1, 22_2, 9_1, and 9_2 are indicated as possible new, potent ellipticine derivatives to be synthesized and biologically tested.

Formation of Amidinyl Radicals via Visible-Light-Promoted Reduction of N-Phenyl Amidoxime Esters and Application to the Synthesis of 2-Substituted Benzimidazoles

We have developed a new method for the synthesis of 2-substituted benzimidazoles via amidinyl radicals generated by visible-light-promoted reduction of N-phenyl amidoxime esters in the presence of an iridium photocatalyst. This is the first report of the use of N-phenyl amidoxime esters as amidinyl radical precursors, and the first use of substituted benzene rings as amidinyl radical acceptors. This method widens the application range of substrates and overcomes the shortcomings of the traditional methods for the synthesis of 2-substituted benzimidazoles, which requires harsh reaction conditions, involves difficult-to-prepare substituted o-phenylenediamine substrates, and produces acidic waste.