Synthesis of 5, 6-diaroylisoindoline-1, 3-dione and computational approaches for investigation on structural and mechanistic insights by DFT

Natural Isatin Derivatives Against Black Fungus: In Silico Studies

During this coronavirus pandemic, when a lot of people are already severely afflicted with SARS-CoV-19, the dispersion of black fungus is making it worse, especially in the Indian subcontinent. Considering this situation, the idea for an in silico study to identify the potential inhibitor against black fungal infection is envisioned and computational analysis has been conducted with isatin derivatives that exhibit considerable antifungal activity. Through this in silico study, several pharmacokinetics properties like absorption, distribution, metabolism, excretion, and toxicity (ADMET) are estimated for various derivatives. Lipinski rules have been used to observe the drug likeliness property, and to study the electronic properties of the molecules, quantum mechanism was analyzed using the density functional theory (DFT). After applying molecular docking of the isatin derivatives with sterol 14-alpha demethylase enzyme of black fungus, a far higher docking affinity score has been observed for the isatin sulfonamide-34 (derivative 1) than the standard fluconazole. Lastly, molecular dynamic (MD) simulation has been performed for 100 ns to examine the stability of the proposed drug complex by estimating Root Mean Square Deviation (RMSD), Radius of gyration (Rg), Solvent accessible surface area (SASA), Root Mean Square Fluctuation (RMSF), as well as hydrogen bond. Listed ligands have precisely satisfied every pharmacokinetics requirement for a qualified drug candidate and they are non-toxic, non-carcinogenic, and have high stability. This natural molecule known as isatin derivative 1 has shown the potential of being a drug for fungal treatment. However, the impact of the chemicals on living cells requires more investigation and research.

Evaluation of Rapanone and Nectandrin B as novel inhibitors for targeting the metastatic regulator protein BACH1 using breast cancer cell line Mcf-7

Cancer formation is defined as the unrestrained proliferation of cells due to various factors acting as a causing agent. A limited number of over-expressed transcription factors are contributed to the development of numerous types of cancer. The metastatic regulator protein BTB And CNC Homology 1 (BACH1) is Cap 'N' Collar (CNC) and it belongs to a basic region leucine zipper (bZIP) family. The presence of the least level concentration of intracellular heme BACH1 forms heterodimers with musculo aponeurotic fibrosarcoma (sMAF) proteins and inhibits or induces the target gene expression. Based on the previous studies, BACH1 plays a critical player in the conditions of senescence and oxidative stress, cycling of cell life, heme degradation pathway and cancer, especially in metastasis. Discovering new anti-cancer drugs (identification of bioactive compounds) stages finally needs to inhibit the target protein. This present study is aimed to screen and identify stability, binding affinity and analysis of pharmacokinetics of selected compounds through structural screening, ADMET, DFT and MESP. From this study, it is revealed that Rapanone and Nectandrin B have the potential to alter the degree of gene expression via binding with the BACH1 allosteric region which will further change the degree of expression of BACH1 downstream target genes involved in the regulation of cancer progression particularly in metastasis. The two plant origin compounds Rapanone and Nectandrin B might be novel candidates for developing anti-cancer drugs. The predicted compounds were further validated through in-vitro experimental approaches.Communicated by Ramaswamy H. Sarma.

Anti-viral drug discovery against monkeypox and smallpox infection by natural curcumin derivatives: A Computational drug design approach

Background

In the last couple of years, viral infections have been leading the globe, considered one of the most widespread and extremely damaging health problems and one of the leading causes of mortality in the modern period. Although several viral infections are discovered, such as SARS CoV-2, Langya Henipavirus, there have only been a limited number of discoveries of possible antiviral drug, and vaccine that have even received authorization for the protection of human health. Recently, another virial infection is infecting worldwide (Monkeypox, and Smallpox), which concerns pharmacists, biochemists, doctors, and healthcare providers about another epidemic. Also, currently no specific treatment is available against Monkeypox. This research gap encouraged us to develop a new molecule to fight against monkeypox and smallpox disease. So, firstly, fifty different curcumin derivatives were collected from natural sources, which are available in the PubChem database, to determine antiviral capabilities against Monkeypox and Smallpox.

Material and method

Preliminarily, the molecular docking experiment of fifty different curcumin derivatives were conducted, and the majority of the substances produced the expected binding affinities. Then, twelve curcumin derivatives were picked up for further analysis based on the maximum docking score. After that, the density functional theory (DFT) was used to determine chemical characterizations such as the highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO), softness, and hardness, etc.

Results

The mentioned derivatives demonstrated docking scores greater than 6.80 kcal/mol, and the most significant binding affinity was at -8.90 kcal/mol, even though 12 molecules had higher binding scores (-8.00 kcal/mol to -8.9 kcal/mol), and better than the standard medications. The molecular dynamic simulation is described by root mean square deviation (RMSD) and root-mean-square fluctuation (RMSF), demonstrating that all the compounds might be stable in the physiological system.

Conclusion

In conclusion, each derivative of curcumin has outstanding absorption, distribution, metabolism, excretion, and toxicity (ADMET) characteristics. Hence, we recommended the aforementioned curcumin derivatives as potential antiviral agents for the treatment of Monkeypox and Smallpox virus, and more in vivo investigations are warranted to substantiate our findings.

Investigation of catalytic effect on carbon-carbon bond formation by Baylis-Hillman (BH) reaction between (2/3/4)-nitro-arylaldehyde and alkylacrylates and computational approaches through DFT functional

The 4-diazabicyclo[2. 2. 2] octane, DABCO, had widely established with gigantic and celestial applications on catalysis for carbon-carbon bond formation reactions. Thus, it has been employed to synthesize the alkyl 2-(hydroxyl (nitrophenyl) methyl)acrylate by the reaction of arylaldehydes and alkylacrylates under a mild condition with good yields. First of all, reaction was examined effect of various solvents, such as water, MeOH, Dioxane, DMSO, t-Butanol, DMF, Toluene, and THF and THF was the best solvent in term of yield. Next, the room temperature (R.T) was the optimized condition than 60 °C and 80 °C. The overall reaction progress was monitored in presence of DABCO, Et₃N, C₂H₅ONa, C₄H₉OK, (CH₃)₃COK and pyridine catalysts with THF solvents at room temperatures, and calculated the amount for superior of catalyst. There was no product obtained in presence of catalysts, such as Et₃N, C₂H₅ONa, C₄H₉OK, (CH₃)₃COK and pyridine. But in present of DABCO, this reaction has proceeded and monitored the concentration of catalyst and various temperature effects on reaction progress. In addition, the computational approaches for speculative investigation of solvents effect has employed for predicating and comparatively verified with the proposed reaction mechanism in presence of DABCO catalyst through the Density Functional Theory (DFT). The most acceptable tools for the thermodynamic had been illustrated to get the reaction kinetics by formation energy, entropy, enthalpy for reactant, product and transition state. Finally, the Gibbs free energy for reactions from the reactants and product has calculated to predict the occurring spontaneously possibility with and without solvents, and it is said that the reaction is spontaneously occurred through the water, DMSO, THF solvent although it is opposed fact without solvent even other solvents. It might be concluded that the optimization conditions of reaction are the THF solvent in presence of 20% DABCO catalyst at room temperature with high (about 90%) throughout 6–8 h where the 4- position of nitro group in arylaldehyde is the most preferable in case of time and yield.