Synthesis biological evaluation and molecular docking of isatin hybrids as anti-cancer and anti-microbial agents

Isatin, known as 1H-indole-2,3-dione, was originally recognised as a synthetic molecule until its discovery in the fruits of the cannonball tree, Couroupita guianensis. It is naturally occurring in plants of the genus Isatis and serves as a metabolic derivative of adrenaline in humans. Isatin possesses significant pharmacological importance, and its synthetic versatility has prompted extensive interest in its derivative compounds due to their diverse biological and pharmacological properties. These derivatives represent a valuable class of heterocyclic compounds with potential applications as precursors for synthesizing numerous valuable drugs. In the pursuit of advancing our research on isatin hybrids, we investigate the utilisation of readily available hydrazonoindolin-2-one and isatin as starting materials for the synthesis of a wide range of analogues. Characterisation of the synthesized compounds was carried out through various analytical techniques. Furthermore, the obtained compounds were subjected to extensive testing to evaluate their anticancer and antimicrobial activities. Specifically, their efficacy against key proteins, namely Staphylococcus aureus protein (PDB ID: 1JIJ), Escherichia coli protein (PDB ID: 1T9U), Pseudomonas aeruginosa protein (PDB ID: 2UV0), and Acinetobacter baumannii protein (PDB ID: 4HKG), was examined through molecular docking calculations. Several molecules, such as 3, 4, 6, 16, and 19, displayed remarkable activity against the renal cancer cell line UO-31. Additionally, the results of antimicrobial activity testing revealed that compound 16 exhibited significant cytotoxicity against Candida albicans and Cryptococcus neoformans. Subsequently, ADME/T calculations were performed to gain insights into the potential effects and reactions of these molecules within human metabolism. This comprehensive study provides valuable insights into the potential pharmacological applications of isatin derivatives and underscores their significance in drug development.

Surface adsorption and corrosion resistance performance of modified chitosan: Gravimetric, electrochemical, and computational studies

Two novel chitosan derivatives (water soluble and acid soluble) modified with thiocarbohydrazide were produced by a quick and easy technique using formaldehyde as links. The novel compounds were synthesized and then characterized by thermogravimetric analysis, elemental analysis, nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, and differential scanning calorimetry. Their surface morphologies were examined using scanning electron microscopy. These chitosan derivatives could produce pH-dependent gels. The behavior of mild steel in 5 % acetic acid, including both inhibitors at various concentrations, was investigated using gravimetric and electrochemical experiments. According to the early findings, both compounds (TCFACN and TCFWCN) functioned as mixed-type metal corrosion inhibitors. Both inhibitors showed their best corrosion inhibition efficiency at 80 mg L-1. TCFACN and TCFWCN, showed approximately 92 % and 94 % corrosion inhibition, respectively, at an optimal concentration of 80 mg L-1, according to electrochemical analysis. In the corrosion test, the water contact angle of the polished MS sample at 87.90 °C was reduced to 51 °C. The water contact angles for MS inhibited by TCFACN and TCFWCN in the same electrolyte were greater, measuring 78.10 °C and 93.10 °C, respectively. The theoretical results also support the experimental findings.

Antioxidant enzyme activities, molecular docking studies, MM-GBSA, and molecular dynamic of chlorpyrifos in freshwater fish Capoeta umbla

Chlorpyrifos (CPF), which was started to be used in 1965, is a broad spectrum organophosphate insecticide that is used more and more day by day. Commonly used to control pests in farmland and homes, CPF is more toxic to fish than organochlorine compounds. CPF poses a serious threat to the health of humans and aquatic organisms. This paper studies the relationship between CPF exposure and antioxidant enzyme activities in gill, kidney and liver tissues of Capoeta umbla. Different time intervals (12, 24, 48, 72, and 96 h) and CPF doses (55 and 110 µg L-1) were used in the study. Spectrophotometrical measures were taken in all tissues for antioxidant enzyme activities and malondialdehyde (MDA) levels, as indices of the lipid peroxidation (LPO). A positive relationship between CPF and MDA levels was found in the study at a statistically significant level (p < 0.05). The study also found a negative relationship between CPF levels and catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), and glutathione reductase (GR) activity. Independent variables in the study can act as biomarkers of CPF exposure. The study recommends employing proper ecotoxicological risk evaluations in cases of CPF usage as a pesticide. The activities of the studied molecules against various proteins that are crystal structure of human peroxiredoxin 5 (PDB ID: 1HD2) has docking score value is -2.67, crystal structure of Bovine Xanthine Oxidase (PDB ID: 3NRZ) has docking score value is -3.76, and crystal structure of antibacterial FabH (PDB ID: 4Z8D) has docking score value is -3.16, were compared. Molecular dynamic (MD) calculations were made in 100 ns. MM/GBSA methods are calculated binding free energy. Afterwards, ADME/T analysis was performed to examine the some properties of the molecules.Communicated by Ramaswamy H. Sarma.

Novel Quinazolinone Derivatives: Potential Synthetic Analogs for the Treatment of Glaucoma, Alzheimer's Disease and Diabetes Mellitus

Quinazolinones, which represent an important part of nitrogen-containing six-membered heterocyclic compounds, are frequently used in drug design due to their wide biological activity properties. Therefore, the novel quinazolinones were synthesized from the reaction of acylated derivatives of 4-hydroxy benzaldehyde with 3-amino-2-alkylquinazolin-4(3H)-ones with good yields (85-94 %) and their structures were characterized using Fourier-transform Infrared (FT-IR), Nuclear Magnetic Resonance (1 H-NMR, 13 C-NMR), and High-Resolution Mass Spectroscopy (HR-MS). As the application of the synthesized compounds, their inhibition properties of the synthesized compounds on α-Glucosidase (α-Glu), Acetylcholinesterase (AChE), Butyrylcholinesterase (BChE), and Carbonic anhydrase I-II (hCA I-II) metabolic enzymes were investigated. All compounds showed inhibition at nanomolar level with the Ki values in the range of 12.73±1.26-93.42±9.44 nM for AChE, 8.48±0.92-25.84±2.59 nM for BChE, 66.17±5.16-818.06±44.41 for α-Glu, 2.56±0.26-88.23±9.72 nM for hCA I, and 1.68±0.14-85.43±7.41 nM for hCA II. Molecular docking study was performed to understand the interactions of the most potent compounds with corresponding enzymes. Also, absorption, distribution, metabolism, excretion, and toxicity (ADME/T) properties of the compounds were investigated.

In Silico Development of Novel Benzofuran-1,3,4-Oxadiazoles as Lead Inhibitors of M. tuberculosis Polyketide Synthase 13

Benzofuran and 1,3,4-oxadiazole are privileged and versatile heterocyclic pharmacophores which display a broad spectrum of biological and pharmacological therapeutic potential against a wide variety of diseases. This article reports in silico CADD (computer-aided drug design) and molecular hybridization approaches for the evaluation of the chemotherapeutic efficacy of 16 S-linked N-phenyl acetamide moiety containing benzofuran-1,3,4-oxadiazole scaffolds BF1-BF16. This virtual screening was carried out to discover and assess the chemotherapeutic efficacy of BF1-BF16 structural motifs as Mycobacterium tuberculosis polyketide synthase 13 (Mtb Pks13) enzyme inhibitors. The CADD study results revealed that the benzofuran clubbed oxadiazole derivatives BF3, BF4, and BF8 showed excellent and remarkably significant binding energies against the Mtb Pks13 enzyme comparable with the standard benzofuran-based TAM-16 inhibitor. The best binding affinity scores were displayed by 1,3,4-oxadiazoles-based benzofuran scaffolds BF3 (-14.23 kcal/mol), BF4 (-14.82 kcal/mol), and BF8 (-14.11 kcal/mol), in comparison to the binding affinity score of the standard reference TAM-16 drug (-14.61 kcal/mol). 2,5-Dimethoxy moiety-based bromobenzofuran-oxadiazole derivative BF4 demonstrated the highest binding affinity score amongst the screened compounds, and was higher than the reference Pks13 inhibitor TAM-16 drug. The bindings of these three leads BF3, BF4, and BF8 were further confirmed by the MM-PBSA investigations in which they also exhibited strong bindings with the Pks13 of Mtb. Moreover, the stability analysis of these benzofuran-1,3,4-oxadiazoles in the active sites of the Pks13 enzyme was achieved through molecular dynamic (MD) simulations at 250 ns virtual simulation time, which indicated that these three in silico predicted bio-potent benzofuran tethered oxadiazole molecules BF3, BF4, and BF8 demonstrated stability with the active site of the Pks13 enzyme.

Sertraline: theoretical studies and a new potentiometric PVC membrane sensor for its determination

Background:

Sertraline (ST) hydrochloride is an anti-depressant of the selective serotonin reuptake inhibitor (SSRI) class. Potentiometric sensors are an appealing route for detecting drugs due to some advantages in terms of sensitivity, feasibility, selectivity, fast response, tolerance to turbidity and colour of solutions, and cost-effectiveness.

Methods:

A mixture of polyvinyl chloride powder (PVC) with o-nitrophenyl octyl ether and the ion association complex was dissolved in tetrahydrofuran (THF) to prepare the membrane for the proposed sensor. The sensor was calibrated and then electrochemically used for detecting ST in pharmaceutical samples.

Results:

The near Nernstian response was observed for a concentration of 1.0 x 10-8 – 1.0 x 10-2 mol L-1 with 58.62 mV as a slope per concentration decade. This direct potentiometric measurement resulted in average recoveries of 96.0 ± 0.2%. Moreover, good selectivity for sertraline with respect to many inorganic and organic cations was observed.

Conclusion:

The proposed sensor was simple to use and produced accurate and precise results. The molecule's chemical and biological activities were revealed using theoretical calculations. Regarding the chemical activities, calculations were made on the 3-21g and 6-31g while the SDD bases were set at B3LYP, HF, and the M062X level. Molecular docking calculations were designed against cancer proteins in order to have details regarding the molecule's biological activity.

Could Peganum harmala be effective in the treatment of COVID-19?

BACKGROUND

Predominant molecules in Peganum harmala leaves were detected using gas chromatography-mass spectrometry (GC-MS). Based on the results of this analysis, most alkaloids, flavonoids and triterpenoids in found P. harmala was compiled from the literature in order to develop and lead the production of effective inhibitor drugs for ACE2, main protease, and RNA dependent RNA polymerase (RdRp) proteins of SARS-CoV-2 virus, which is today's most contagious and deadly disease.

AIM

By comparing FDA-approved drugs used in the treatment of COVID-19, we aimed to determine whether the molecules in P. harmala are effective against SARS CoV-2 in silico.

RESULTS AND CONCLUSION

P. harmala molecules were selected as drug candidates from the PubChem web tool. Afterwards, molecular docking calculations of these inhibitor molecules were made with Maestro Molecular modeling program by Schrödinger. The comparison of molecules with high inhibitory activities with FDA-approved drugs was made. With molecular mechanics Poisson-Boltzmann surface area (MM-PBSA) calculations, docking calculations of molecules that have high inhibitory activity, were tried to be verified by calculations in the range of 0-100 nanoseconds (Tab. 4, Fig. 6, Ref. 53).

Determination of inhibitor activity of drugs against the COVID-19

BACKGROUND

It is the SARS-CoV-2 virus, one of the most significant diseases of today's world. Due to the high transmission of this disease, studies are ongoing to discover an inhibitor drug that can stop this disease. In this study, inhibitory drugs used for many diseases were tried to stop the SARS-CoV-2 virus.

AIM

In the calculations made, inhibitor molecules for the SARS-CoV-2 virus were calculated by molecular docking method.

RESULTS AND CONCLUSION

Inhibitory activities of SARS-CoV-2 virus against spike glycoprotein (PDB ID: 6M0J, 6LZG), main protease (PDB ID: 5RGG, 6WTT), and RNA dependent RNA polymerase (RdRp) (PDB ID: 6YYT, 7BV2) proteins were compared. Then, docking calculations were supported by calculations by MM-PSBA of the inhibitor with the highest activity. Afterwards, it was compared with FDA approved drugs for the SARS-CoV-2 virus. It was found that the Carvedilol molecule was the best against RNA dependent RNA polymerase (RdRp) protein of SARS-CoV-2 (Tab. 4, Fig. 9, Ref. 42).

Synthesis, biological activity and docking calculations of bis-naphthoquinone derivatives from Lawsone

Some metabolic enzyme inhibitors can be used as Multi-target-Directed-Ligands (MTDL) in Medicinal chemistry therefore, synthesis and determination of alternative inhibitors are essential. In this study, novel bis-napthoquinone derivatives (5a-o) were synthesized through a multi-component cascade reaction of two molecules of 2-hydroxy-1,4-naphthoquinone with an aromatic aldehyde in basic media using triethylamine as a catalyst. This novel heterocyclic derivatives (5a-o) are applied to inhibit the carbonic anhydrase (hCA I and hCA II) isoform in low levels of nano molecules with Ki values exist between 4.62 ± 1.01 to 70.45 ± 9.03 nM for hCA I and for hCA II which is physiologically dominant K_is values are in the range of 5.61 ± 1.04 to 73.26 ± 10.25 nM. Further these novel derivatives (5a-o) efficiently inhibit AChE with Ki values in the range of 0.13 ± 0.02 to 3.16 ± 0.56 nM. The compounds are also applied for BChE with Ki values varying between 0.50 ± 0.10 to 9.23 ± 1.15 nM. For α-glycosidase, the most efficient Ki values of 5e and 5f are 76.14 ± 9.60 and 95.27 ± 12.55 nM respectively. Finally, molecular docking calculations against enzymes (acetylcholinesterase, butyrylcholinesterase, and the human carbonic anhydrase I and II) are compared using biological activities of heterocyclic derivatives. After these calculations, an ADME/T analysis is performed to study the future medicinal use of heterocyclic derivatives from lawsone.

Could boron-containing compounds (BCCs) be effective against SARS-CoV-2 as anti-viral agent?

BACKGROUND

Seven dioxaborole compounds are investigated in this study. Structural and spectral characterizations are done at the M062X/6-31+G(d,p) level in water. Active sites of these compounds are determined by contour plots of frontier molecular orbital and molecular electrostatic potential (MEP) maps. Electrophilic and nucleophilic attack regions are determined. Since SARS-CoV-2 is a worldwide health problem, antiviral properties of studied boron-containing compounds are investigated by molecular docking calculations. In addition to these calculations, MM/PSBA calculations are performed.

RESULTS AND CONCLUSION

It is found that the studied boron compounds can be good drug candidates against the main protease of SARS-CoV-2, while the best of them is 4,6-di-tert-butyl-2-(4-methoxyphenyl)benzo[d][1,3,2] dioxaborole (B2) (Tab. 3, Fig. 8, Ref. 23).

Synthesis and docking calculations of tetrafluoronaphthalene derivatives and their inhibition profiles against some metabolic enzymes

Syntheses of tetrahydroepoxy, O-allylic, O-prenylic, and O-propargylic tetrafluoronaphthalene derivatives, starting from 1-bromo-2,3,4,5,6-pentafluorobenzene, are reported here for the first time. The O-substituted tetrafluoronaphthalene derivatives were designed and also synthesized via a one-pot nucleophilic substitution reaction in excellent yields, whereas the tetrafluorotetrahydroepoxynaphthalene derivate was synthesized via a reduction reaction in excellent yield. The chemical structures of all the synthesized molecules were characterized by nuclear magnetic resonance, infrared spectroscopy, and high-resolution mass spectrometry techniques. In this study, a series of novel tetrafluoronaphthalene derivatives (2, 2a, 4-6) was tested toward several enzymes including α-glucosidase, acetylcholinesterase (AChE), and human carbonic anhydrase I and II (hCA I/II). The tetrafluoronaphthalene derivatives 2, 2a, and 4-6 showed IC₅₀ and K_i values in the range of 0.83-1.27 and 0.71-1.09 nM against hCA I, 1.26-1.85 and 1.45-5.31 nM against hCA II, 39.02-56.01 and 20.53-56.76 nM against AChE, and 15.27-34.12 and 22.58-30.45 nM against α-glucosidase, respectively. Molecular docking calculations were made to determine the biological activity values of the tetrafluoronaphthalene derivatives against the enzymes. After the calculations, ADME/T analysis was performed to examine the effects on human metabolism. Finally, these compounds had antidiabetic and anticholinesterase potentials.

Are clarithromycin, azithromycin and their analogues effective in the treatment of COVID19?

BACKGROUND

SARS-CoV-2, which started in Wuhan and later affected the whole world, is the most important disease of the world today. Many ways to inhibit SARS-CoV-2 virus are sought to prevent the spread of this virus. Azithromycin and clarithromycin are considered for the treatment of the SARS-CoV-2 virus, which has a high similarity to previous colonic diseases.

AIM

We aimed to determine whether azithromycin and clarithromycin, the RNA-dependent RNA polymerase protein inhibitor used in the treatment of COVID-19, is effective against SARS Cov-2 in silico.

RESULTS AND CONCLUSION

The 503 analogues of azithromycin and clarithromycin were studied to target SARS-CoV-2 the RNA-dependent RNA polymerase protein inhibition. Maestro program was used to compare the inhibition activities of these analogues. A detailed comparison was made using the numerical value of many parameters obtained. ADME / T properties were then examined to determine the effects and reactions of analogues on human metabolism. In this study, the SARS-CoV2 virus is 6NUR and 6NUS, which is the RNA-dependent RNA polymerase protein. Among these proteins, the best inhibitor among the 503 analogues according to the docking score parameter was 9851445 with a great difference. This analogue was an analogue of azithromycin (Tab. 3, Fig. 6, Ref. 58).

Metal contained Phthalocyanines with 3,4-Dimethoxyphenethoxy substituents: their anticancer, antibacterial activities and their inhibitory effects on some metabolic enzymes with molecular docking studies

The compounds (3-6) used in this study were re-synthesized in accordance with our previous study. The inhibitory effect of the complexes on some metabolic enzymes was examined and it was demonstrated that the enzymes inhibited by ligands and their complex molecules at micromolar level. The best Ki value for α-glycosidase enzyme was absorved 1.01±0.08 µM for compound 6. The biological activity of ligand and metal complexes against enzymes was compared with molecular docking method. The enzymes used against ligand and metal complexes respectively: Achethylcholinesterase for ID 4M0E (AChE), butyrylcholinesterase for ID 5NN0 (BChE), α-glycosidase for ID 1XSI (α-Gly). ADME analysis was performed to examine the drug properties of the compounds (3-6). Besides, the anticancer properties of the complexes were studied. The doses of all compounds caused significant reductions in MCF-7 cell viability. The 3 and 5 compounds administered to PC-3 cells exhibited a more pronounced cytotoxic effect than the other two compounds (4 and 6). Furthermore, antibacterial activities of these compounds against Escherichia coli and Staphylococcus aureus were examined.Communicated by Ramaswamy H. Sarma.

The biological activities, molecular docking studies, and anticancer effects of 1-arylsuphonylpyrazole derivatives

This work is devoted to definition of the direction of reaction between 1-benzenesulfonylimino pyridinium chloride and α- or β-halo-containing sulfamides, chloroacetic acid, 1-chloro-2,3-dihydroxypropane, etc. The optimal conditions for the synchronous reaction of heterocyclization are determined. Benzenesulfonyliminopyridinium chloride was obtained to form pyrazolopyridines with 1,2-polarophiles, and pyridazine pyridines with 1,3-polarophiles. These novel derivatives were found as effective inhibitors of the α-glycosidase with K_i values in the range of 13.66 ± 2.63-60.63 ± 12.71 nM. The molecules (II-X) against enzyme were compared theoretically with the help of molecular docking to compare biological activities. The results were compared with the numerical values of the parameters obtained from molecular docking calculations and found to be in great agreement with the experimental results. However, ADME analysis of molecules was performed. Also, the compounds exhibited significant anticancer effect depending on the doses administered.Communicated by Ramaswamy H. Sarma.

4D-QSAR Study of Some Pyrazole Pyridine Carboxylic Acid Derivatives By Electron Conformational-Genetic Algorithm Method

INTRODUCTION

In the present work, pharmacophore identification and biological activity prediction for 86 pyrazole pyridine carboxylic acid derivatives were made using the electron conformational genetic algorithm approach which was introduced as a 4D-QSAR analysis by us in recent years. In the light of the data obtained from quantum chemical calculations at HF/6-311 G** level, the Electron Conformational Matrices of Congruity (ECMC) were constructed by EMRE software. Comparing the matrices, electron conformational submatrix of activity (ECSA, Pha) was revealed that are common for these compounds within a minimum tolerance. A parameter pool was generated considering the obtained pharmacophore.

METHODS

To determine the theoretical biological activity of molecules and identify the best subset of variables affecting bioactivities, we used the nonlinear least square regression method and genetic algorithm.

RESULTS

The results obtained in this study are in good agreement with the experimental data presented in the literature. The model for training and test sets attained by the optimum 12 parameters gave highly satisfactory results with R2 training= 0.889, q2=0.839 and SEtraining=0.066, q2 ext1 = 0.770, q2 ext2 = 0.750, q2 ext3=0.824, ccctr = 0.941, ccctest = 0.869 and cccall = 0.927.