Tin(II) triflate Catalysed Synthesis of 3-Methyleneisoindolin-1-ones

Photoredox Synthesis of Silicon-Containing Isoindolin-1-ones and Deuterated Analogues Through Hydrosilylation and Deuterium-silylation

An efficient, practical, and metal-free protocol for the synthesis of silicon-containing isoindolin-1-ones and deuterated analogues via the synergistic combination of an organic photoredox and hydrogen atom transfer process is described. This strategy features mild reaction conditions, high atom economy, and excellent functional group compatibility, delivering a myriad of structurally diverse and valuable products with good to excellent yields.

Copper-Catalyzed Asymmetric Hydroboration Reaction of Novel Methylene Isoindolinone Compounds through Microwave Irradiation and Their Antileishmanial and Antitoxoplasma Activities

The aim of this study was devoted into molecular docking calculations to discover the potential antileishmania and antitoxoplasma activities of newly synthesized compounds obtained by applying a practical and simple method under microwave irradiation. All these compounds were tested in vitro for their biological activity against Leishmania major promastigotes, amastigotes, and Toxoplasma gondii tachyzoites. Compounds 2a, 5a, and 5e were the most active against both L. major promastigotes and amastigotes, with IC₅₀ values of less than 0.4 μM mL^-1. Compounds 2c, 2e, 2h, and 5d had a strong antitoxoplasma activity of less than 2.1 μM mL^-1 against T. gondii. We can conclude that aromatic methyleneisoindolinones are potently active against both L. major and T. gondii. Further studies for mode of action evaluation are recommended. Compounds 5c and 5b are the best drug candidates for antileishmania and antitoxoplasma due to their SI values being over 13. The docking studies of compounds 2a-h and 5a-e against pteridine reductase 1 and T. gondii enoyl acyl carrier protein reductase reveal that compound 5e may be an effective antileishmanial and antitoxoplasma drug discovery initiative.

Computational analysis of protein-ligand interaction by targeting a cell cycle restrainer

BACKGROUND AND OBJECTIVE

The cyclin-dependent kinases 4/6 (CDK4/6) are among the most crucial controllers of the cell cycle, and their abnormal activity may induce uncontrolled cell multiplication, leading to cancers. The FDA currently approved three CDK4/6 inhibitors, however, they are associated with a variety of side effects. Thus it is required to design/develop novel potent and safe CDK4/6 inhibitors.

METHODS

In the present work, we furnished an integrated in-silico approach followed by steered molecular dynamics (SMD) simulations to identify molecules that can be developed into novel CDK4/6 inhibitors.

RESULTS

Out of thirty-two 3-methyleneisoindolin-1-one molecules we selected top three M18, M24, and M32 molecules as potential drug candidates based on their respective interaction energies. According to the robust 250 ns MD simulations and thermodynamic free energy, M24 was the best molecule in comparison to palbociclib. In SMD, M24 required ∼205.587 kJ/mol/nm external pulling force, while palbociclib needed ∼160.97 kJ/mol/nm to dissociate from the binding pocket of the CDK4.

CONCLUSIONS

The high pulling force required for M24 dissociation from the binding site denotes stronger binding with CDK4. Therefore, M24 offers the possibility of a critical starting structure in developing effective CDK4 inhibitors.

Novel 3-Methyleneisoindolinones Diversified via Intramolecular Heck Cyclization Induce Oxidative Stress, Decrease Mitochondrial Membrane Potential, Disrupt Cell Cycle, and Induce Apoptosis in Head and Neck Squamous Cell Carcinoma Cells

Head and neck squamous cell carcinoma (HNSCC) is the sixth most prevalent cancer in the world and the most prevalent cancer of developing countries. Increased disease burden and a smaller number of approved targeted therapies are a growing concern worldwide. Isoindolinone motifs have been a central part of many pharmacological compounds, and their derivatives possess substantial anticancer potential. However, their anticancer potential against HNSCC has not been well investigated. In the current study, a series of 3-methyleneisoindolinones have been designed and synthesized and their late-stage intramolecular Heck cyclization was achieved to evaluate their anticancer potential against HNSCC cells. Additionally, in silico ADME profiling of synthesized compounds revealed their drug-likeness properties as potential drug candidates. Among the synthesized compounds, 3-bromo-5-methylpyridin-2-yl-3-methyleneisoindolin-1-one, i.e., 3n, with a pyridyl unit exhibited the most significant cytotoxicity against HNSCC cells. The cytotoxic potential of synthesized compounds varied depending on the nature of substituents present and has been well established with structure-activity relationship studies. Further, flow cytometric analysis showed that 3f, 3h, and 3n triggered intracellular oxidative stress, disrupted mitochondrial membrane potential, and interrupted the cell cycle of HNSCC cells in the S-phase and sub-G1 phase. Further, 3f, 3h, and 3n also exhibited pro-apoptotic potential and induced cellular apoptosis in the HNSCC cells. Overall, the findings of this study attributed 3-methyleneisoindolinone chemistry and efficacy evaluation and corroborated their anticancer potential against HNSCC. It will pave the way to further design and optimize novel 3-methyleneisoindolinone as effective antitumor agents, which may provide effective treatment modalities against HNSCC.

Photoredox Hydroxy-arylation of the Terminal Double Bond of N-Substituted 3-Methyleneisoindolin-1-ones in Visible Light

Mild and efficient ruthenium-catalyzed hydroxy-arylation of the terminal double bond of N-substituted 3-methyleneisoindolin-1-ones is described. The reaction takes place with aryl diazonium salt as the arylating reagent and water as the hydroxyl source in visible light at ambient temperature. The strategy entails vicinal difunctionalization of alkene and enables construction of 3-benzyl-3-hydroxyisoindolin-1-one heterocyclic scaffolds in moderate to good yields. C-C and C-O bonds are formed in one pot without any external additive and oxidant through an in situ generation of a carbocation intermediate in green light.

Different Lewis Acid Promotor-Steered Highly Regioselective Phosphorylation of Tertiary Enamides

Different Lewis acid promotor-steered highly regioselective phosphorylation of tertiary enamides with diverse H-phosphonates or H-phosphine oxides was developed. Under the catalysis of iron salt, the phosphonyl group was introduced into the α-position of tertiary enamides, affording various α-phosphorylated amides in high efficiency. On the other hand, the β-phosphorylated tertiary enamides were efficiently obtained as the products in the presence of manganese(III) acetylacetonate.

A lesson for the maestro of the replication fork: Targeting the protein-binding interface of proliferating cell nuclear antigen for anticancer therapy

The proliferating cell nuclear antigen (PCNA) has emerged as a promising candidate for the development of novel cancer therapeutics. PCNA is a nononcogenic mediator of DNA replication that regulates a diverse range of cellular functions and pathways through a comprehensive list of protein-protein interactions. The hydrophobic binding pocket on PCNA offers an opportunity for the development of inhibitors to target various types of cancers and modulate protein-protein interactions. In the present study, we explored the binding modes and affinity of molecule I1 (standard molecule) with the previously suggested dimer interface pocket and the hydrophobic pocket present on the frontal side of the PCNA monomer. We also identified potential lead molecules from the library of in-house synthesized 3-methylenisoindolin-1-one based molecules to inhibit the protein-protein interactions of PCNA. Our results were based on robust computational methods, including molecular docking, conventional, steered, and umbrella sampling molecular dynamics simulations. Our results suggested that the standard inhibitor I1 interacts with the hydrophobic pocket of PCNA with a higher affinity than the previously suggested binding site. Also, the proposed molecules showed better or comparable binding free energies as calculated by the Molecular Mechanics Poisson-Boltzmann Surface Area (MMPBSA) approach and further validated by enhanced umbrella sampling simulations. In vitro and in vivo methods could test the computationally suggested molecules for advancement in the drug discovery pipeline.