In silico development of potential InhA inhibitors through 3D-QSAR analysis, virtual screening and molecular dynamics.

Tuberculosis is one of the most ancient infectious diseases known to mankind predating upper Paleolithic era. In the current scenario, treatment of drug resistance tuberculosis is the major challenge as the treatment options are limited, less efficient and more toxic. In our study we have developed an atom based 3D QSAR model, statistically validated sound with R2 > 0.90 and Q2 > 0.72 using reported direct inhibitors of InhA (2018-2022), validated by enzyme inhibition assay. The model was used to screen a library of 3958 molecules taken from Binding DB and candidates molecules with promising predicted activity value (pIC50) > 5) were selected for further analyzed screening by using molecular docking, ADME profiling and molecular dynamic simulations. The lead molecule, ZINC11536150 exhibited good docking score (glideXP = -11.634 kcal/mol) compared to standard triclosan (glideXP = -7.129 kcal/mol kcal/mol) and through molecular dynamics study it was observed that the 2nv6-complex of ZINC11536150 with Mycobacterium tuberculosis InhA (PDB entry: 2NV6) complex remained stable throughout the entire simulation time of 100 ns.Communicated by Ramaswamy H. Sarma.

A computational investigation of thymidylate synthase inhibitors through a combined approach of 3D-QSAR and pharmacophore modelling.

Thymidylate synthase (TS) is a crucial target of cancer drug discovery and is mainly involved in the De novo synthesis of the DNA precursor thymine. In the present study, to generate reliable models and identify a few promising molecules, we combined QSAR modelling with the pharmacophore hypothesis-generating technique. Input molecules were clustered on their similarity, and a cluster of 74 molecules with a pyrimidine moiety was chosen as the set for 3D-QSAR and pharmacophore modelling. Atom-based and field-based 3D-QSAR models were generated and statistically validated with R2 > 0.90 and Q2 > 0.75. The common pharmacophore hypothesis(CPH) generation identified the best six-point model ADHRRR. Using these best models, a library of FDA-approved drugs was screened for activity and filtered via molecular docking, ADME profiling, and molecular dynamics simulations. The top ten promising TS-inhibiting candidates were identified, and their chemical features profitable for TS inhibitors were explored.Communicated by Ramaswamy H. Sarma.

A Review on Benzimidazole Scaffolds as Inhibitors of Mycobacterium tuberculosis Mycolyl-arabinogalactan-peptidoglycan Complex Biosynthesis.

BACKGROUND: Tuberculosis is one of the oldest known infectious diseases to mankind, caused by Mycobacterium tuberculosis. Although current treatment using first-line anti-tubercular drugs is proven to be effective, an infection caused by resistant strains, as in multidrug-resistant and extensive drug- resistant tuberculosis is still an impending challenge to treat. OBJECTIVE: Our objective is to focus on reporting benzimidazole derivatives that are targeting mycobacterial membrane biosynthesis, particularly the mycobacterial mycolyl-arabinogalactanpeptidoglycan complexes. From the literature survey, it has been noted that targeting Mycobacterium tuberculosis cell membrane biosynthesis is an effective approach to fight against drug resistance in tuberculosis. METHODS: Articles on benzimidazole derivatives as inhibitors of proteins responsible for the biosynthesis of the mycobacterial mycolyl-arabinogalactan-peptidoglycan complex have been selected. RESULTS: By reviewing the anti-tubercular activity of the reported benzimidazole derivatives, we have concluded that a correlation between benzimidazole derivatives and their biological activity is found. It has been noted that benzimidazole derivatives with substitution at N1, C2, C5, and C6 positions have shown a greater affinity towards target proteins. CONCLUSION: Even though scientific advancement toward the prevention of tuberculosis has been quite significant in the past few decades, infection caused by resistant strains is a major concern. We have collected data on benzimidazole derivatives that inhibit the biosynthesis of mycolic acid, arabinogalactan and, peptidoglycan. From our observations, we conclude that majority of the molecules have given anti-tubercular activity in nanomolar range. Still there are few mycobacterial membrane biosynthesis proteins where benzimidazole as an inhibitor has yet to be explored.

Formulating the Structural Aspects of Various Benzimidazole Cognates.

BACKGROUND: Benzimidazole derivatives are widely used in clinical practice as potential beneficial specialists. Recently, the neuroprotective effect of derivatives of benzimidazole moiety has also shown positive outcomes. OBJECTIVES: To develop favourable molecules for various neurodegenerative disorders using the versatile chemical behaviour of the benzimidazole scaffold. METHODS: About 25 articles were collected that discussed various benzimidazole derivatives and categorized them under various subheadings based on the targets such as BACE 1, JNK, MAO, choline esterase enzyme, oxidative stress, mitochondrial dysfunction in which they act. The structural aspects of various benzimidazole derivatives were also studied. CONCLUSION: To manage various neurodegenerative disorders, a multitargeted approach will be the most hopeful stratagem. Some benzimidazole derivatives can be considered for future studies, which are mentioned in the discussed articles.

Deciphering the detailed structure-activity relationship of coumarins as Monoamine oxidase enzyme inhibitors-An updated review.

In the last few years, Monoamine oxidase (MAO) have emerged as a target for the treatment of many neurodegenerative diseases including anxiety, depression, Alzheimer's, and Parkinson's diseases. The MAO inhibitors especially selective and reversible inhibitors of either of the isoenzymes (MAO-A & MAO-B) have been given more attention as both the form have different therapeutic properties and hence can be used for different neurological disorders. The lack of selective and reversible inhibitors available for both the enzymes and severity of the neuronal disorder in society have opened a new door to the researchers to carry out large and dedicated researches in this field. Among the several classes of the molecule as the inhibitors, coumarins hold a rank as a potent scaffold with its ease of synthesis, high therapeutic potential, and reversibility in inhibiting MAOs. The current review is an update of the research in the field that covers the works during the last six years (2014-2020) with a major focus on the SAR of the coumarin derivatives including synthetic, natural, and hybrids of coumarins with FDA-approved drugs.