Exploring Ventilator-Associated Pneumonia: Microbial Clues and Biomarker Insights from a Retrospective Study.

Background and Objectives: Ventilator-associated pneumonia (VAP) is a common complication in critically ill patients receiving mechanical ventilation. The incidence rates of VAP vary, and it poses significant challenges due to microbial resistance and the potential for adverse outcomes. This study aims to explore the microbial profile of VAP and evaluate the utility of biomarkers and illness severity scores in predicting survival. Materials and Methods: A retrospective cohort study was conducted involving 130 patients diagnosed with VAP. Microbial analysis of bronchoalveolar lavage (BAL) fluid, as well as measurements of C-reactive protein (CRP) and procalcitonin (PCT) levels, were performed. Sequential Organ Failure Assessment (SOFA) and Acute Physiology and Chronic Health Evaluation II (APACHE II) scores were calculated to assess illness severity. Statistical analyses were conducted to determine correlations and associations. Results: The study revealed that Klebsiella pneumoniae (K. pneumoniae) (50.7%) and Pseudomonas aeruginosa (P. aeruginosa) (27.69%) were the most identified microorganisms in VAP cases. SOFA (p-value < 0.0001) and APACHE II (p-value < 0.0001) scores were effective in assessing the severity of illness and predicting mortality in VAP patients. Additionally, our investigation highlighted the prognostic potential of CRP levels (odds ratio [OR]: 0.980, 95% confidence interval [CI] 0.968 to 0.992, p = 0.001). Elevated levels of CRP were associated with reduced survival probabilities in VAP patients. Conclusion: This study highlights the microbial profile of VAP and the importance of biomarkers and illness severity scores in predicting survival. Conclusions: The findings emphasize the need for appropriate management strategies to combat microbial resistance and improve outcomes in VAP patients.

Covalent small-molecule inhibitors of SARS-CoV-2 Mpro: Insights into their design, classification, biological activity, and binding interactions.

Since 2020, many compounds have been investigated for their potential use in the treatment of SARS-CoV-2 infection. Among these agents, a huge number of natural products and FDA-approved drugs have been evaluated as potential therapeutics for SARS-CoV-2 using virtual screening and docking studies. However, the identification of the molecular targets involved in viral replication led to the development of rationally designed anti-SARS-CoV-2 agents. Among these targets, the main protease (Mpro) is one of the key enzymes needed in the replication of the virus. The data gleaned from the crystal structures of SARS-CoV-2 Mpro complexes with small-molecule covalent inhibitors has been used in the design and discovery of many highly potent and broad-spectrum Mpro inhibitors. The current review focuses mainly on the covalent type of SARS-CoV-2 Mpro inhibitors. The design, chemistry, and classification of these inhibitors were also in focus. The biological activity of these inhibitors, including their inhibitory activities against Mpro, their antiviral activities, and the SAR studies, were discussed. The review also describes the potential mechanism of the interaction between these inhibitors and the catalytic Cys145 residue in Mpro. Moreover, the binding modes and key binding interactions of these covalent inhibitors were also illustrated. The covalent inhibitors discussed in this review were of diverse chemical nature and origin. Their antiviral activity was mediated mainly by the inhibition of SARS-CoV-2 Mpro, with IC50 values in the micromolar to the nanomolar range. Many of these inhibitors exhibited broad-spectrum inhibitory activity against the Mpro enzymes of other coronaviruses (SARS-CoV-1 and MERS-CoV). The dual inhibition of the Mpro and PLpro enzymes of SARS-CoV-2 could also provide higher therapeutic benefits than Mpro inhibition. Despite the approval of nirmatrelvir by the FDA, many mutations in the Mpro enzyme of SARS-CoV-2 have been reported. Although some of these mutations did not affect the potency of nirmatrelvir, there is an urgent need to develop a second generation of Mpro inhibitors. We hope that the data summarized in this review could help researchers in the design of a new potent generation of SARS-CoV-2 Mpro inhibitors.

Ecofriendly HPLC Method for Simultaneous Determination of the Co-Prescribed Drugs in Chemotherapy Omeprazole, Ondansetron and Deflazacort in Spiked Human Plasma.

Green, selective and accurate high-performance liquid chromatography (HPLC) chromatographic method is presented for simultaneous separation and quantitation of the co-prescribed drugs in chemotherapy omeprazole, ondansetron and deflazacort in spiked human plasma. An isocratic HPLC separation was performed on X Bridge C18 (4.6 × 250 mm) column with 5 µm particle size using mobile phase consisting of methanol: ammonium acetate buffer pH 4 adjusted by acetic acid (60: 40, v/v). The injection volume was 20µL with UV detection wavelength at 237 nm at room temperature. Flow rate of the mobile phase was adjusted to be 2.0 ml/min. Dexamethasone was used as internal standard to correct the variation during sample pretreatment. FDA guidelines were followed to validate the developed method. Successful application of the developed method was revealed by simultaneous determination of omeprazole, ondansetron and deflazacort in spiked human plasma in ranges of 1-20, 0.1-8 and 0.2-8 µg mL-1 for omeprazole, ondansetron and deflazacort, respectively. Four greenness assessment tools were used to evaluate the greenness of the developed method and the results were accepted. This method permitted the accurate simultaneous determination of the studied drugs, thus it can be used during therapeutic drug monitoring in daily clinical practice.

Pyrrolizine/indolizine-bearing (un)substituted isoindole moiety: design, synthesis, antiproliferative and MDR reversal activities, and in silico studies.

Two new series of pyrrolizine/indolizine derivative-bearing (un)substituted isoindole moiety were designed and synthesized. The anticancer potential of the new compounds was evaluated against hepatocellular carcinoma (HepG-2), colorectal carcinoma, colon cancer (HCT-116), and breast cancer (MCF-7) cell lines. Compounds 6d and 6o were the most potent derivatives with IC50 values ranging from 6.02 to 13.87 µM against HePG-2, HCT-116, and MCF-7 cell lines. Moreover, methyl analog of the fluoro-substituted indolizine derivative 6m revealed significant antiproliferative activity against HePG-2, HCT-116, and MCF-7 cancer cell lines with IC50 values of 11.97, 28.37, and 19.87 µM, respectively. The most active anticancer analogs, 6d, 6m, and 6o, were inspected for their putative mechanism of action by estimating their epidermal growth factor receptor (EGFR) and cyclin-dependent kinase (CDK 2) inhibitory activities. Thus, compound 6o displayed the most inhibitory activity against EGFR and CDK 2 with IC50 values of 62 and 118 nM, respectively. Additionally, the quantitative real-time PCR analysis for the P-glycoprotein effect of compounds 6d, 6m, and 6o was performed, in which compound 6o illustrated significant down-regulation of P-gp against the HepG-2 cell line by 0.2732 fold. Mechanistic studies for the most active compounds involving the reversal doxorubicin (DOX) effect of compounds 6d, 6m, and 6o were performed, which illustrated cytotoxic activity with IC50 22.27, 3.88, and 8.79 µM, respectively. Moreover, the apoptotic activity of the most active derivative 6o on HCT-116 cancer cells showed accumulation in the G1 and S phases of the cell cycle.

Discovery and optimization of 2,3-diaryl-1,3-thiazolidin-4-one-based derivatives as potent and selective cytotoxic agents with anti-inflammatory activity.

Several studies have indicated the potential therapeutic outcomes of combining selective COX-2 inhibitors with tubulin-targeting anticancer agents. In the current study, a novel series of thiazolidin-4-one-based derivatives (7a-q) was designed by merging the pharmacophoric features of some COXs inhibitors and tubulin polymerization inhibitors. Compounds 7a-q were synthesized and evaluated for their cytotoxic activity against MCF7, HT29, and A2780 cancer cell lines (IC50 = 0.02-17.02 µM). The cytotoxicity of 7a-q was also assessed against normal MRC5 cells (IC50 = 0.47-13.46 µM). Compounds 7c, 7i, and 7j, the most active in the MTT assay, significantly reduced the number of HT29 colonies compared to the control. Compounds 7c, 7i, and 7j also induced significant decreases in the tumor volumes and masses in Ehrlich solid carcinoma-bearing mice compared to the control. The three compounds also exhibited significant anti-HT29 migration activity in the wound-healing assay. They have also induced cell cycle arrest in HT29 cells at the S and G2/M phases. In addition, they induced significant increases in both early and late apoptotic events in HT29 cells compared to the control, where 7j showed the highest effect. On the other hand, compound 7j (1 µM) displayed weak inhibitory activity against tubulin polymerization compared to colchicine (3 µM). On the other hand, compounds 7a-q inhibited the activity of COX-2 (IC50 = 0.42-29.11 µM) compared to celecoxib (IC50 = 0.86 µM). In addition, 7c, 7i, and 7j showed moderate inhibition of inflammation in rats compared to indomethacin, with better GIT safety profiles. Molecular docking analysis revealed that 7c, 7i, and 7j have higher binding free energies towards COX-2 than COX-1. These above results suggested that 7j could serve as a potential anticancer drug candidate.

Ecofriendly Chromatographic Assay of Metformin Combinations; Content Uniformity Tests and Toxicity Profiling.

Accurate, sensitive and green HPTLC chromatographic method was proposed for simultaneous determination of metformin, glipizide and sitagliptin in the presence of metformin potential toxic impurities melamine and cyanoguanidine. The separation was completed on silica gel HPTLC F254 plates using a mixture of ethyl acetate: methanol: ammonia: formic acid (7: 2: 0.2: 0.2, by volume) as a developing system with UV scanning for the developed bands at 235 nm. The Rf values for metformin, glipizide, sitagliptin, melamine and cyanoguanidine were 0.17, 0.84, 0.67, 0.47 and 0.75, respectively. Linear responses were observed in the ranges of 0.2-3, 0.07-1.5, 1.5-5, 0.8-4 and 0.4-2 µg/band with correlation coefficients of 0.9999, 0.9998, 0.9997, 0.9996 and 0.9998 for metformin, glipizide, sitagliptin, melamine and cyanoguanidine, respectively. The proposed method was validated as per ICH criteria with respect to linearity, accuracy, precision, specificity and robustness. The validated method was successfully applied for determination of the studied drugs in Janumet® and Engilor® tablets; also, the results were statistically compared to those obtained by the reported spectrophotometric method and no significant difference was found between them. This method permitted the accurate simultaneous determination of the studied drugs, indicating its ability to be used for routine quality control assays of these drugs.

Integration of immunoinformatics and cheminformatics to design and evaluate a multitope vaccine against Klebsiella pneumoniae and Pseudomonas aeruginosa coinfection.

Introduction: Klebsiella pneumoniae (K. pneumoniae) and Pseudomonas aeruginosa (P. aeruginosa) are the most common Gram-negative bacteria associated with pneumonia and coinfecting the same patient. Despite their high virulence, there is no effective vaccine against them. Methods: In the current study, the screening of several proteins from both pathogens highlighted FepA and OmpK35 for K. pneumonia in addition to HasR and OprF from P. aeruginosa as promising candidates for epitope mapping. Those four proteins were linked to form a multitope vaccine, that was formulated with a suitable adjuvant, and PADRE peptides to finalize the multitope vaccine construct. The final vaccine's physicochemical features, antigenicity, toxicity, allergenicity, and solubility were evaluated for use in humans. Results: The output of the computational analysis revealed that the designed multitope construct has passed these assessments with satisfactory scores where, as the last stage, we performed a molecular docking study between the potential vaccine construct and K. pneumonia associated immune receptors, TLR4 and TLR2, showing affinitive to both targets with preferentiality for the TLR4 receptor protein. Validation of the docking studies has proceeded through molecular dynamics simulation, which estimated a strong binding and supported the nomination of the designed vaccine as a putative solution for K. pneumoniae and P. aeruginosa coinfection. Here, we describe the approach for the design and assessment of our potential vaccine.

Design, Synthesis, Molecular docking, and biological evaluation of novel 2,3-diaryl-1,3-thiazolidine-4-one derivatives as potential anti-inflammatory and cytotoxic agents.

A new series of 2,3-diaryl-1,3thiazolidin-4-one derivatives was designed, synthesized, and evaluated for their cytotoxicity and COXs inhibitory activities. Among these derivatives, compounds 4 k and 4j exhibited the highest inhibitory activities against COX-2 at IC50 values of 0.05 and 0.06 µM, respectively. Compounds 4a, 4b, 4e, 4 g, 4j, 4 k, 5b, and 6b, which exhibited the highest inhibition% against COX-2, were evaluated for their anti-inflammatory activity in rats. Results showed 41.08-82.00 % inhibition of paw edema thickness by the test compounds compared to celecoxib (inhibition% = 89.51 %). In addition, compounds 4b, 4j, 4 k, and 6b exhibited better GIT safety profiles compared to celecoxib and indomethacin. The four compounds were also evaluated for their antioxidant activity. The results revealed the highest antioxidant activity for 4j (IC50 = 45.27 µM) comparable to torolox (IC50 = 62.03 µM). The antiproliferative activity of the new compounds was evaluated against HePG-2, HCT-116, MCF-7, and PC-3 cancer cell lines. The results showed the highest cytotoxicity for compounds 4b, 4j, 4 k, and 6b (IC50 = 2.31-27.19 µM), with 4j being the most potent. Mechanistic studies revealed the ability of 4j and 4 k by inducing marked apoptosis and cell cycle arrest at the G1 phase in HePG-2 cancer cells. These biological results may also suggest a role for COX-2 inhibition in the antiproliferative activity of these compounds. The results of the molecular docking study for 4 k and 4j into the active site of COX-2 revealed good fitting and correlation with the results of the in vitro COX­2 inhibition assay.

Computational Analysis of Deleterious SNPs in NRAS to Assess Their Potential Correlation With Carcinogenesis.

The NRAS gene is a well-known oncogene that acts as a major player in carcinogenesis. Mutations in the NRAS gene have been linked to multiple types of human tumors. Therefore, the identification of the most deleterious single nucleotide polymorphisms (SNPs) in the NRAS gene is necessary to understand the key factors of tumor pathogenesis and therapy. We aimed to retrieve NRAS missense SNPs and analyze them comprehensively using sequence and structure approaches to determine the most deleterious SNPs that could increase the risk of carcinogenesis. We also adopted structural biology methods and docking tools to investigate the behavior of the filtered SNPs. After retrieving missense SNPs and analyzing them using six in silico tools, 17 mutations were found to be the most deleterious mutations in NRAS. All SNPs except S145L were found to decrease NRAS stability, and all SNPs were found on highly conserved residues and important functional domains, except R164C. In addition, all mutations except G60E and S145L showed a higher binding affinity to GTP, implicating an increase in malignancy tendency. As a consequence, all other 14 mutations were expected to increase the risk of carcinogenesis, with 5 mutations (G13R, G13C, G13V, P34R, and V152F) expected to have the highest risk. Thermodynamic stability was ensured for these SNP models through molecular dynamics simulation based on trajectory analysis. Free binding affinity toward the natural substrate, GTP, was higher for these models as compared to the native NRAS protein. The Gly13 SNP proteins depict a differential conformational state that could favor nucleotide exchange and catalytic potentiality. A further application of experimental methods with all these 14 mutations could reveal new insights into the pathogenesis and management of different types of tumors.

A Comprehensive Overview of Globally Approved JAK Inhibitors.

Janus kinase (JAK) is a family of cytoplasmic non-receptor tyrosine kinases that includes four members, namely JAK1, JAK2, JAK3, and TYK2. The JAKs transduce cytokine signaling through the JAK-STAT pathway, which regulates the transcription of several genes involved in inflammatory, immune, and cancer conditions. Targeting the JAK family kinases with small-molecule inhibitors has proved to be effective in the treatment of different types of diseases. In the current review, eleven of the JAK inhibitors that received approval for clinical use have been discussed. These drugs are abrocitinib, baricitinib, delgocitinib, fedratinib, filgotinib, oclacitinib, pacritinib, peficitinib, ruxolitinib, tofacitinib, and upadacitinib. The aim of the current review was to provide an integrated overview of the chemical and pharmacological data of the globally approved JAK inhibitors. The synthetic routes of the eleven drugs were described. In addition, their inhibitory activities against different kinases and their pharmacological uses have also been explained. Moreover, their crystal structures with different kinases were summarized, with a primary focus on their binding modes and interactions. The proposed metabolic pathways and metabolites of these drugs were also illustrated. To sum up, the data in the current review could help in the design of new JAK inhibitors with potential therapeutic benefits in inflammatory and autoimmune diseases.

Optimization and SAR investigation of novel 2,3-dihydropyrazino[1,2-a]indole-1,4-dione derivatives as EGFR and BRAFV600E dual inhibitors with potent antiproliferative and antioxidant activities.

Using a single drug to treat cancer with dual-targeting is an unusual approach when compared to other drug combinations. Dual-targeting agents were developed as a result of insufficient efficacy and drug resistance when single-targeting agents were used. As a result, the 2,3-dihydropyrazino[1,2-a]indole-1,4-dione derivatives 13-22 have been developed as dual EGFR and BRAFV600E inhibitors. The target compounds were synthesized and tested in vitro against four cancer cell lines, with compounds 15, and 19-22 demonstrating potent antiproliferative activity. In vitro studies revealed that these compounds have dual inhibitory effect on EGFR and BRAFV600E. Compounds 15, and 19-22 exhibited inhibitions of EGFR with IC50 ranging from 32 nM to 63 nM which were superior to erlotinib (IC50 = 80 ± 10 nM). Compounds 20, 21 and 22 showed promising inhibitory activity of BRAFV600E (IC50 = 55, 45 and 51 nM, respectively) and were found to be potent inhibitors of cancer cell proliferation (GI50 = 51, 35 and 44 nM, respectively). Compounds 20, 21 and 22 showed good antioxidant activity comparable to the reference Trolox. Lastly, the best active dual inhibitors were docked inside EGFR and BRAFV600E active sites to clarify their binding modes.

Docking studies of sesquiterpene lactones isolated from Ambrosia maritima L. reveals their potential anti-inflammatory and cytotoxic activities.

Five sesquiterpene lactones were isolated and identified from Ambrosia maritima L. Hymenin showed highest cytotoxic activity against HCT-116, A-549, and MCF-7 cell lines (IC50= 3.83 ± 0.2, 5.48 ± 0.3, 10.1 ± 0.6 µg/mL, respectively). Damsin has significant COX-2 inhibitory activity (IC50=33.97 ± 1.62 µg/mL) while hymenin showed highest selectivity to COX-1 (IC50 = 18.21 µg/mL) and significant inhibition of NO (IC50=18.19 ± 0.75 µg/mL). The docking study revealed nice fitting into COX-1/2 and a higher binding affinity for maritimolide towards human Src kinase compared to the native ligand, Bosutinib. Results suggested that both COXs/Src kinase inhibition could contribute even partially to the overall mechanism of cytotoxic activity of the five compounds. The structure-activity relationship revealed that α-methylene-γ-lactone moiety enhances the cytotoxic activity, OH group at C-1 increase activity of hymenin. However, the reduction of the double bond at C-2 as in damsin resulted in a significant decrease in activity against HCT-116 and MCF-7 cells.

In Silico Designing of a Multitope Vaccine against Rhizopus microsporus with Potential Activity against Other Mucormycosis Causing Fungi.

During the current era of the COVID-19 pandemic, the dissemination of Mucorales has been reported globally, with elevated rates of infection in India, and because of the high rate of mortality and morbidity, designing an effective vaccine against mucormycosis is a major health priority, especially for immunocompromised patients. In the current study, we studied shared Mucorales proteins, which have been reported as virulence factors, and after analysis of several virulent proteins for their antigenicity and subcellular localization, we selected spore coat (CotH) and serine protease (SP) proteins as the targets of epitope mapping. The current study proposes a vaccine constructed based on top-ranking cytotoxic T lymphocyte (CTL), helper T lymphocyte (HTL), and B cell lymphocyte (BCL) epitopes from filtered proteins. In addition to the selected epitopes, ß-defensins adjuvant and PADRE peptide were included in the constructed vaccine to improve the stimulated immune response. Computational tools were used to estimate the physicochemical and immunological features of the proposed vaccine and validate its binding with TLR-2, where the output data of these assessments potentiate the probability of the constructed vaccine to stimulate a specific immune response against mucormycosis. Here, we demonstrate the approach of potential vaccine construction and assessment through computational tools, and to the best of our knowledge, this is the first study of a proposed vaccine against mucormycosis based on the immunoinformatics approach.

Icotinib, Almonertinib, and Olmutinib: A 2D Similarity/Docking-Based Study to Predict the Potential Binding Modes and Interactions into EGFR.

In the current study, a 2D similarity/docking-based study was used to predict the potential binding modes of icotinib, almonertinib, and olmutinib into EGFR. The similarity search of icotinib, almonertinib, and olmutinib against a database of 154 EGFR ligands revealed the highest similarity scores with erlotinib (0.9333), osimertinib (0.9487), and WZ4003 (0.8421), respectively. In addition, the results of the docking study of the three drugs into EGFR revealed high binding free energies (ΔGb = -6.32 to -8.42 kcal/mol) compared to the co-crystallized ligands (ΔGb = -7.03 to -8.07 kcal/mol). Analysis of the top-scoring poses of the three drugs was done to identify their potential binding modes. The distances between Cys797 in EGFR and the Michael acceptor sites in almonertinib and olmutinib were determined. In conclusion, the results could provide insights into the potential binding characteristics of the three drugs into EGFR which could help in the design of new more potent analogs.

Pyrrolizine/Indolizine-NSAID Hybrids: Design, Synthesis, Biological Evaluation, and Molecular Docking Studies.

In the current study, eight new hybrids of the NSAIDs, ibuprofen and ketoprofen with five pyrrolizine/indolizine derivatives were designed and synthesized. The chemical structures of these hybrids were confirmed by spectral and elemental analyses. The antiproliferative activities of these hybrids (5 µM) was investigated against MCF-7, A549, and HT-29 cancer cell lines using the cell viability assay, MTT assay. The results revealed 4-71% inhibition of the growth of the three cancer cell lines, where 8a,e,f were the most active. In addition, an investigation of the antiproliferative activity of 8a,e,f against MCF-7 cells revealed IC50 values of 7.61, 1.07, and 3.16 µM, respectively. Cell cycle analysis of MCF-7 cells treated with the three hybrids at 5 µM revealed a pro-apoptotic increase in cells at preG1 and cell cycle arrest at the G1 and S phases. In addition, the three hybrids induced early apoptotic events in MCF-7 cells. The results of the molecular docking of the three hybrids into COX-1/2 revealed higher binding free energies than their parent compounds 5a,c and the co-crystallized ligands, ibuprofen and SC-558. The results also indicated higher binding free energies toward COX-2 over COX-1. Moreover, analysis of the binding modes of 8a,e,f into COX-2 revealed partial superposition with the co-crystallized ligand, SC-558 with the formation of essential hydrogen bonds, electrostatic, or hydrophobic interactions with the key amino acid His90 and Arg513. The new hybrids also showed drug-likeness scores in the range of 1.06-2.03 compared to ibuprofen (0.65) and ketoprofen (0.57). These results above indicated that compounds 8a,e,f deserve additional investigation as potential anticancer candidates.

Globally Approved EGFR Inhibitors: Insights into Their Syntheses, Target Kinases, Biological Activities, Receptor Interactions, and Metabolism.

Targeting the EGFR with small-molecule inhibitors is a confirmed valid strategy in cancer therapy. Since the FDA approval of the first EGFR-TKI, erlotinib, great efforts have been devoted to the discovery of new potent inhibitors. Until now, fourteen EGFR small-molecule inhibitors have been globally approved for the treatment of different types of cancers. Although these drugs showed high efficacy in cancer therapy, EGFR mutations have emerged as a big challenge for these drugs. In this review, we focus on the EGFR small-molecule inhibitors that have been approved for clinical uses in cancer therapy. These drugs are classified based on their chemical structures, target kinases, and pharmacological uses. The synthetic routes of these drugs are also discussed. The crystal structures of these drugs with their target kinases are also summarized and their bonding modes and interactions are visualized. Based on their binding interactions with the EGFR, these drugs are also classified into reversible and irreversible inhibitors. The cytotoxicity of these drugs against different types of cancer cell lines is also summarized. In addition, the proposed metabolic pathways and metabolites of the fourteen drugs are discussed, with a primary focus on the active and reactive metabolites. Taken together, this review highlights the syntheses, target kinases, crystal structures, binding interactions, cytotoxicity, and metabolism of the fourteen globally approved EGFR inhibitors. These data should greatly help in the design of new EGFR inhibitors.

Discovery of novel oxazole-based macrocycles as anti-coronaviral agents targeting SARS-CoV-2 main protease.

We have discovered a family of synthetic oxazole-based macrocycles to be active against SARS-CoV-2. The synthesis, pharmacological properties, and docking studies of the compounds are reported in this study. The structure of the new macrocycles was confirmed by NMR spectroscopy and mass spectrometry. Compounds 13, 14, and 15a-c were evaluated for their anti-SARS-CoV-2 activity on SARS-COV-2 (NRC-03-nhCoV) virus in Vero-E6 cells. Isopropyl triester 13 and triacid 14 demonstrated superior inhibitory activities against SARS-CoV-2 compared to carboxamides 15a-c. MTT cytotoxicity assays showed that the CC50 (50% cytotoxicity concentration) of 13, 14, and 15a-c ranged from 159.1 to 741.8 µM and their safety indices ranged from 2.50 to 39.1. Study of the viral inhibition via different mechanisms of action (viral adsorption, replication, or virucidal property) showed that 14 had mild virucidal (60%) and inhibitory effects on virus adsorption (66%) at 20 µM concentrations. Compound 13 displayed several inhibitory effects at three levels, but the potency of its action is primarily virucidal. The inhibitory activity of compounds 13, 14, and 15a-c against the enzyme SARS-CoV-2 Mpro was evaluated. Isopropyl triester 13 had a significant inhibition activity against SARS-CoV-2 Mpro with an IC50 of 2.58 µM. Large substituents on the macrocyclic template significantly reduced the inhibitory effects of the compounds. Study of the docking of the compounds in the SARS CoV-2-Mpro active site showed that the most potent macrocycles 13 and 14 exhibited the best fit and highest affinity for the active site binding pocket. Taken together, the present study shows that the new macrocyclic compounds constitute a new family of SARS CoV-2-Mpro inhibitors that are worth being further optimized and developed.

In Silico Approach Using Free Software to Optimize the Antiproliferative Activity and Predict the Potential Mechanism of Action of Pyrrolizine-Based Schiff Bases.

In the current study, a simple in silico approach using free software was used with the experimental studies to optimize the antiproliferative activity and predict the potential mechanism of action of pyrrolizine-based Schiff bases. A compound library of 288 Schiff bases was designed based on compound 10, and a pharmacophore search was performed. Structural analysis of the top scoring hits and a docking study were used to select the best derivatives for the synthesis. Chemical synthesis and structural elucidation of compounds 16a-h were discussed. The antiproliferative activity of 16a-h was evaluated against three cancer (MCF7, A2780 and HT29, IC50 = 0.01-40.50 µM) and one normal MRC5 (IC50 = 1.27-24.06 µM) cell lines using the MTT assay. The results revealed the highest antiproliferative activity against MCF7 cells for 16g (IC50 = 0.01 µM) with an exceptionally high selectivity index of (SI = 578). Cell cycle analysis of MCF7 cells treated with compound 16g revealed a cell cycle arrest at the G2/M phase. In addition, compound 16g induced a dose-dependent increase in apoptotic events in MCF7 cells compared to the control. In silico target prediction of compound 16g showed six potential targets that could mediate these activities. Molecular docking analysis of compound 16g revealed high binding affinities toward COX-2, MAP P38α, EGFR, and CDK2. The results of the MD simulation revealed low RMSD values and high negative binding free energies for the two complexes formed between compound 16g with EGFR, and CDK2, while COX-2 was in the third order. These results highlighted a great potentiality for 16g to inhibit both CDK2 and EGFR. Taken together, the results mentioned above highlighted compound 16g as a potential anticancer agent.

Novel pyrrolizines bearing 3,4,5-trimethoxyphenyl moiety: design, synthesis, molecular docking, and biological evaluation as potential multi-target cytotoxic agents.

In the present study, two new series of pyrrolizines bearing 3,4,5-trimethoxyphenyl moiety were designed, synthesised, and evaluated for their cytotoxic activity. The benzamide derivatives 16a-e showed higher cytotoxicity than their corresponding Schiff bases 15a-e. Compounds 16a,b,d also inhibited the growth of MCF-7/ADR cells with IC50 in the range of 0.52-6.26 µM. Interestingly, the new compounds were less cytotoxic against normal MRC-5 cells (IC50=0.155-17.08 µM). Mechanistic studies revealed the ability of compounds 16a,b,d to inhibit tubulin polymerisation and multiple oncogenic kinases. Moreover, compounds 16a,b,d induced preG1 and G2/M cell cycle arrest and early apoptosis in MCF-7 cells. The molecular docking analyses of compounds 16a,b,d into the active site in tubulin, CDK-2, and EGFR proteins revealed higher binding affinities compared to the co-crystallised ligands. These preliminary results suggested that compounds 16a,b,d could serve as promising lead compounds for the future development of new potent anticancer agents.HighlightsTwo new series of pyrrolizines bearing 3,4,5-trimethoxyphenyl moieties were synthesized.Compounds 16a,b,d displayed the highest cytotoxicity against the three cancer cell lines.Kinase profiling test revealed inhibition of multiple oncogenic kinases by compounds 16a,b,d.Compounds 16a,b,d exhibited weak to moderate inhibition of tubulin-polymerization.Compounds 16a,b,d induced preG1 and G2/M cell cycle arrest and early apoptosis in MCF-7 cells.Docking studies revealed high binding affinities for compounds 16a,b towards tubulin and CDK-2.

Design, synthesis, and biological evaluation of novel EGFR inhibitors containing 5-chloro-3-hydroxymethyl-indole-2-carboxamide scaffold with apoptotic antiproliferative activity.

New EGFR inhibitor series of fifteen 5-chloro-3-hydroxymethyl-indole-2-carboxamide derivatives has been designed, synthesized, and tested for antiproliferative activity against a panel of cancer cell lines. The results showed that p-substituted phenethyl derivatives 10, 11, 13, 15 and 17-19 showed superior antiproliferative activity compared to their m-substituted counterparts 12, 14, 16 and 20. Compounds 15, 16, 19 and 20 displayed promising EGFR inhibitory activity as well as an increase in caspase 3 levels. Compounds 15 and 19 increased caspase-8 and 9 levels, as well as inducing Bax and decreasing Bcl-2 protein levels. Compound 19 demonstrated cell cycle arrest at pre-G1 and G2/M phases. The results of the docking study into the active site of EGFR revealed strong fitting of the new compounds with higher binding affinities compared to erlotinib.