Synthesis and in vitro studies for structure-based design of novel chalcones as antitubercular agents targeting InhA

Isolation and in-silico approach of Modified Embelin derivative from Embelia ribes fruits as anti-Alzheimer agent

Embelin is one of the primary compounds present in the Embelia ribes fruit. Embelin has a broader pharmacological activity such as Anti-inflammatory, anti-bacterial, antioxidant, and many more. The ultimate aim of the study is to ensure the impact of reduced embelin in the management of Alzheimer's disease. Embelin was isolated and modified by the reduction method, and the Modified Embelin derivative (MED) 3-Undecylcyclohexa-2,5-diene-1,2,4,5-tetraol was analysed through FT-IR, NMR, and Mass Spectroscopic techniques. MED was docked against acetylcholinesterase (AChE) amyloid beta (Aβ) receptors PDB ID: 1EVE & 1B68, respectively. The docking scores remain similar to that of positive standards galantamine and Donepezil.

Halogenated chalcones against Mycobacterium tuberculosis targeting InhA: Rational design, in silico and in vitro evaluation

A library of 25-series compounds was designed against Mycobacterium Tuberculosis (M.tb) to identify novel antitubercular drugs. In silico inhibition of InhA, an essential component of FAS-II, was successfully achieved. The drug ability, lead-likeness, and toxicity of the compounds were assessed using Swiss ADME, pkCSM, and Osiris Property Explorer, which revealed the potential for drug development of chalcone compounds. Through in silico research, it was confirmed that toxic-free compounds could bind to InhA. It was found that all of the compounds bind to InhA with binding affinities ranging from -7.78 to -10.29 kcal/mol-1 which is higher than the reference standard Isoniazid and Pyrazinamide. The top five compounds were synthesized from 15 toxic-free compounds. The structural characteristics of the compounds were determined using IR, NMR, and mass spectrometry techniques. These findings indicate that these substances are competitive, reversible, and specific InhA inhibitors of InhA. using the Alamar Blue assay method (H37RV, ATCC No. 27294), the in vitro anti-mycobacterial activity of each of the synthesized compounds against M.tb was evaluated. The two most powerful compounds were (2E)-3-[4-(benzyloxy)-3,5-dimethylphenyl] and (2E)-1-(3,5-dibromophenyl)-3-(3-phenoxyphenyl) prop-2-en-1-one. In the MABA Assay, the MIC for 1-(3,5-dibromophenyl) prop-2-en-1-one was 6.25 μg/ml.

Isolation of 6-gingerol and semi-synthesis of 1,4-benzodiazepines derivatives: An in-situ pharmacokinetics properties, molecular docking and molecular dynamics simulation assessments

This paper outlines a methodical approach for isolating 6-gingerol (1a) from Zingiber officinale Roscoe rhizomes on a gram-scale, resulting in a product of high purity and significant yield. Further, 6-gingerol (1a) [SSG1] derivatives, including 1-(4-hydroxy-3-methoxyphenyl)decane-3,5-dione (1ab), were synthesized via a semi-synthetic pathway involving DMP-mediated fast oxidation and replication. Subsequently, a new series of 1,4-benzodiazepines (3a-c) was synthesized quantitatively using a basic technique. This synthesis necessitated the interaction of 1ab with various o-phenylenediamine (2a-c) compounds. Spectroscopic methods were employed to characterize the synthesized 1,4-benzodiazepines (3a-c)[SSG2, SSG3 & SSG4]. Despite extensive investments by pharmaceutical companies in traditional drug research and development for diseases like type 2 diabetes (T2D), successful treatments remain elusive. Medication repurposing has gained traction as a strategy to address not only diabetes but also other disorders. Leveraging existing molecular pharmacology data accelerates the development of new medications. This paper underscores the importance of repurposing traditional medicines to combat a range of communicable and non-communicable diseases, offering a promising avenue for therapeutic advancement. Additionally, molecular docking studies suggested that one derivative (SSG2) exhibited stronger binding affinity compared to the reference standards. Overall, the findings of this study highlight the potential of semi-synthetic gingerol derivatives for the development of novel therapeutic agents.

Novel strategies based on natural products and synthetic derivatives to overcome resistance in Mycobacterium tuberculosis

One of the biggest health challenges of today's world is the emergence of antimicrobial resistance (AMR), which renders conventional therapeutics insufficient and urgently demands the generation of novel antimicrobial strategies. Mycobacterium tuberculosis (M. tuberculosis), the pathogen causing tuberculosis (TB), is among the most successful bacteria producing drug-resistant infections. The versatility of M. tuberculosis allows it to evade traditional anti-TB agents through various acquired and intrinsic mechanisms, rendering TB among the leading causes of infectious disease-related mortality. In this context, researchers worldwide focused on establishing novel approaches to address drug resistance in M. tuberculosis, developing diverse alternative treatments with varying effectiveness and in different testing phases. Overviewing the current progress, this paper aims to briefly present the mechanisms involved in M. tuberculosis drug-resistance, further reviewing in more detail the under-development antibiotics, nanotechnological approaches, and natural therapeutic solutions that promise to overcome current treatment limitations.

Furan-based Chalcone Annihilates the Multi-Drug-Resistant Pseudomonas aeruginosa and Protects Zebra Fish Against its Infection

The emergence of carbapenem-resistant Pseudomonas aeruginosa, a multi-drug-resistant bacteria, is becoming a serious public health concern. This bacterium infects immunocompromised patients and has a high fatality rate. Both naturally and synthetically produced chalcones are known to have a wide array of biological activities. The antibacterial properties of synthetically produced chalcone were studied against P. aeruginosa. In vitro, study of the compound (chalcone derivative named DKO1), also known as (2E)-1-(5-methylfuran-2-yl)-3-(4-nitrophenyl) prop-2-en-1-one, had substantial antibacterial and biofilm disruptive action. DKO1 effectively shielded against P. aeruginosa-induced inflammation, oxidative stress, lipid peroxidation, and apoptosis in zebrafish larvae. In adult zebrafish, the treatment enhanced the chances of survivability and reduced the sickness-like behaviors. Gene expression, biochemical analysis, and histopathology studies found that proinflammatory cytokines (TNF-α, IL-1β, IL-6, iNOS) were down regulated; antioxidant enzymes such as superoxide dismutase (SOD) and catalase (CAT) levels increased, and histoarchitecture was restored in zebrafish. The data indicate that DKO1 is an effective antibacterial agent against P. aeruginosa demonstrated both in vitro and in vivo.

Insight on sarcopenic obesity and epicatechin as a promising treatment option

BACKGROUND AND AIM

Sarcopenic Obesity (SO) in the elderly population is a complex and multifactorial condition which refers to the loss of skeletal muscle mass, strength, and function associated with aging, while obesity involves excessive adipose tissue accumulation. The simultaneous occurrence of these two conditions presents a unique set of challenges to public health and clinical management. This narrative review aims to provide an overview of the use of epicatechin (EC) in the treatment of SO and its related complications.

METHOD

A survey of studies related to preclinical and clinical evidence of Epicatechin in sarcopenic obesity and its complications was performed in the following database Medline, Scopus, ProQuest, Embase, Web of Science, and Google scholar. Followed by structural activity relationship and pharmacokinetic profile of Epicatechin was discussed in this paper.

RESULTS

The main pharmacological effect of Epicatechin is myostatin inhibition activity which has been described by both in vitro and in vivo studies earlier. The SO is directly correlated with the alteration of Myostatin. The pre-clinical and clinical studies suggest that epicatechin can be a potential candidate in the management of SO and its related complication.

CONCLUSION

The present review describes the pharmacokinetic profile and structural activity of epicatechin respective to SO and its related complications. The goal of this review is to update the scientific community on the therapeutic potential of epicatechin in SO and age-related factors. Conduction of clinical and pre-clinical trials, also drug dosage optimization may provide with insights on the use of epicatechin in SO.

Synthesis of quercetin-iron (Fe) complex and its in silico and in vitro confirmation towards antibacterial activity

Aim: In this study quercetin-iron complex (QFC) was synthesized, and the structural characterizations such as x-ray diffraction, field emission-scanning electron microscopy, energy-dispersive x-ray and Brunner-Emmitt-Teller adsorption-desorption isotherm analysis revealed the crystallinity state, surface morphology and nature of the adsorbing surface with surface area value. Methodology: Functional characterizations such as UV-visible spectrometric and Fourier transform infrared analysis collectively indicated the chemical changes that appeared after complex formation in terms of characteristic change in the spectrum and band position, respectively. Results: The in vitro antibacterial activity against Escherichia coli and Staphylococcus aureus has shown a dose-dependent decrease in colony count and achieved significant removal at 15 mg/ml concentration of QFC. Conclusion: The molecular docking study supports the therapeutic application of QFC.

Synthesis of novel furan-based chalcone derivatives as anti-tuberculosis agents: in vitro, cytotoxicity assessment and in silico

Background: The aim of the study is to identify a novel furan-based chalcone derivative as potent inhibitor against the H37Rv strain. Materials & methods: The in silico pharmacokinetic characteristics, toxicity tests, molecular modeling, chemical synthesis and minimum inhibitory concentration (MIC; IC50) were carried out to evaluate the antitubercular potential of the synthesized furan-based chalcone analogues against H37Rv. Results & conclusion: Among the ten target compounds synthesized, DF02, DF05 and DF07 had MIC values of 1.6 μg/ml equivalent to isoniazid and DF10 showed MIC values of 3.25 μg/ml which is equipotent to pyrazinamide. All the other compounds had optimal concentrations 6.25-100 μg/ml against the H37Rv strain. Compounds DF02 and DF10 were further evaluated for cytotoxicity assay performed using HeLa cell lines.

Design, synthesis and anti-Tb evaluation of chalcone derivatives as novel inhibitors of InhA

A series of halogenated chalcone derivatives were designed and developed for anti-tubercular activity. Novel molecules were designed and in-silico screening were performed using admetSAR, SwissADME, and Osiris Property Explorer. From the initial filter the top 10 compounds were docked using the Autodock tool 1.5.6. and the binding energies of the docked compounds were higher than the standard drugs Isoniazid.and Ethionamide. Based on the in-silico and docking results, the top halogenated chalcones were synthesized and characterized using FT-IR, mass spectrometry, 1H, and 13C NMR spectroscopy. The chalcones were further evaluated for anti-tubercular activity using MABA against the H37Rv strain. Among the series of compounds, DK12 and DK14 showed potent in-vitro activity, with MICs of 0.8 µg/ml, in comparison with 1.6 µg/ml of the first-line drug Isoniazid. Further molecular dynamics simulations studies for 100 ns revealed that the key interaction with TYR 158 were observed in both DK12 and DK14 in the InhA active site. The compound DK12 further showed significant interactions with PHE 149 and ARG 153 residues and is a hit molecule among the series. Further DK12 and DK14 does not show any significance toxicity. The compounds DK12 needs to be optimized and further investigation to be carried out against InhA.Communicated by Ramaswamy H. Sarma.

Comprehensive coverage on anti-mycobacterial endeavour reported during 2022

TB being one of the deadliest diseases and second most common infectious cause of deaths, poses the severe threat to global health. The extended duration of therapy owing to resistance and its upsurge in immune-compromised patients have been the driving force for the development of novel of anti-TB scaffolds. Recently, we have compiled the account of anti-mycobacterial scaffolds published during 2015-2020 and updated them in 2021. The present work involves the insights on the anti-mycobacterial scaffolds reported in 2022 with their mechanism of action, structure activity relationships, along with the key perceptions for the design of newer anti-TB agents for the broader interests of medicinal chemists.

Green synthesis of silver nanoparticles from Cassia Auriculata: Targeting antibacterial, antioxidant activity, and evaluation of their possible effects on saltwater microcrustacean, Artemia Nauplii (non-target organism)

Due to their huge surface area to volume ratio, metallic nanoparticles are becoming increasingly important in numerous spheres of life. Here, initially, we aimed to evaluate the potential use of Cassia auriculata (CA) extract to synthesize silver nanoparticles (AgNPs). Then, we evaluated its antimicrobial potential and antioxidant capacity, as well as performed in silico analysis, and investigated the possible non-toxic effect of AgNPs on Artemia nauplii. Fourier transform infrared (FTIR) spectroscopy, scanning and transmission electron microscopy (SEM/TEM), energy dispersive spectroscopy (EDX), X-ray diffraction (XRD), and dynamic light scattering (DLS) studies were used to characterize the biosynthesized AgNPs. Our data indicate that Bacillus cereus, Escherichia coli, Klebsiella pneumoniae, and Staphylococcus aureus bacteria were susceptible to the biosynthesized AgNPs, whose effect was concentration-response. With a ZOI of 10 mm, the AgNPs were most efficient against gram-positive B. cereus bacteria at the highest concentration (75 μg/mL). The biosynthesized AgNPs (at 25 to 125 μg/mL) showed good antioxidant activity in the DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) and FRAP (ferric reducing antioxidant power) assays. Oleanolic acid from CA exhibited strong binding affinity and high binding energy to E. coli and B. cereus (-9.66 and - 9.74 kcal/mol) on in silico research. According to the comparative non-toxicity analysis, AgNPs, AgNO3, and CA bark extract had the least toxic effects on A. nauplii, with respective mortality rates of 28.14, 32.26, and 38.42 %, respectively. In conclusion, the current work showed that AgNPs produced from CA bark could be a promising material for diverse applications.

Isolation and In silico Study of Curcumin from Curcuma longa and Its Anti-Diabetic Activity

Natural products have been widely used for the management of various diseases that affect human health. Natural products are chemical substances that can be extracted with solvents and isolated by column chromatography techniques from the plant source. The development of new drugs from natural products is still challenging, and the most extensively studied plant material is turmeric, Curcuma longa, which is the chief source of curcumin. Curcumin is a bright yellow solid. In our present study, we have taken Curcuma longa, which is defatted with hexane, followed by being extracted with methanol as a solvent. The turmeric methanolic extract is taken for the isolation of curcumin. This was carried out and confirmed by spectroscopy techniques including ¹H NMR, ¹³C NMR, ESI-HRMS, and FT-IR. The compound in silico ADME properties estimate falls within an acceptable range, and a molecular docking analysis shows that it has a higher binding affinity than reference standards. Based on the findings, it can be said that curcumin, a natural substance, has good therapeutic qualities when it is isolated.

Synthesize palladium nanoparticles from the macroalgae Sargassum fusiforme: An eco-friendly tool in the fight against Plasmodium falciparum?

Although numerous drugs are practiced to control malaria and its vectors, more recently, eco-friendly control tools have been proposed to battle its etiologic agents. Thus, using green bionanotechnology approaches, we aimed to synthesize palladium nanoparticles (Pd NPs) from the macroalgae Sargassum fusiforme (Sf), its potential antiparasitic activity against P. falciparum, as well as its possible cytotoxicity, in HeLa cells. After the biosynthesis of the PdSf NPs, their characterization was carried out by UV-Vis, FESEM, and EDX analyses, and their hydrodynamic size, zeta potential, and surface area were determined. Furthermore, the functional groups of the PdSf NPs were analyzed by FT-IR and GC-MS. While PdSf NPs had an IC50 of 7.68 μg/mL (Chloroquine (CQ)-s) and 16.42 μg/mL, S. fusiforme extract had an IC50 of 14.38 μg/mL (CQ-s) and 35.27 μg/mL (CQ-r). With an IC50 value of 94.49 μg/mL, PdSf NPs exhibited the least toxic effect on the HeLa cells. The Lipinski rule of five and ADMET prediction were used to assess the in silico models of caffeine acid hexoside and quercetin 7-O-hexoside for the presence of drug-like properties. Pathogenic proteins, primarily responsible for motility, binding, and disease-causing, were the target of the structurally based docking studies between plant-derived compounds and pathogenic proteins. Thus, our study pioneered promising results that support the potential antiplasmodial activity of eco-friendly synthesized PdSf NPs using S. fusiforme extract against P. falciparum, opening perspectives for further exploration into the use of these NPs in malaria therapy.