Novel guanidine derivatives targeting leukemia as selective Src/Abl dual inhibitors: Design, synthesis and anti-proliferative activity.

A new series of benzene-sulfonamide derivatives 3a-i was designed and synthesized via the reaction of N-(pyrimidin-2-yl)cyanamides 1a-i with sulfamethazine sodium salt 2 as dual Src/Abl inhibitors. Spectral data IR, 1H-, 13C- NMR and elemental analyses were used to confirm the structures of all the newly synthesized compounds 3a-i and 4a-i. Crucially, we screened all the synthesized compounds 3a-i against NCI 60 cancer cell lines. Among all, compound 3b was the most potent, with IC50 of 0.018 µM for normoxia, and 0.001 µM for hypoxia, compared to staurosporine against HL-60 leukemia cell line. To verify the selectivity of this derivative, it was assessed against a panel of tyrosine kinase EGFR, VEGFR-2, B-raf, ERK, CK1, p38-MAPK, Src and Abl enzymes. Results revealed that compound 3b can effectively and selectively inhibit Src/Abl with IC500.25 µM and Abl inhibitory activity with IC500.08 µM, respectively, and was found to be more potent on these enzymes than other kinases that showed the following results: EGFR IC500.31 µM, VEGFR-2 IC500.68 µM, B-raf IC500.33 µM, ERK IC501.41 µM, CK1 IC500.29 µM and p38-MAPK IC500.38 µM. Moreover, cell cycle analysis and apoptosis performed to compound 3b against HL-60 suggesting its antiproliferative activity through Src/Abl inhibition. Finally, molecular docking studies and physicochemical properties prediction for compounds 3b, 3c, and 3 h were carried out to investigate their biological activities and clarify their bioavailability.

Quinazoline-chalcone hybrids as HDAC/EGFR dual inhibitors: Design, synthesis, mechanistic, and in-silico studies of potential anticancer activity against multiple myeloma.

Two new series of quinazoline-chalcone hybrids were designed, synthesized as histone deacetylase (HDAC)/epidermal growth factor receptor (EGFR) dual inhibitors, and screened in vitro against the NCI 60 human cancer cell line panel. The most potent derivative, compound 5e bearing a 3,4,5-trimethoxyphenyl chalcone moiety, showed the most effective growth inhibition value against the panel of NCI 60 human cancer cell lines. Thus, it was selected for further investigation for NCI 5 log doses. Interestingly, this trimethoxy-substituted analog inhibited the proliferation of Roswell Park Memorial Institute (RPMI)-8226 cells by 96%, at 10 µM with IC50 = 9.09 ± 0.34 µM and selectivity index = 7.19 against normal blood cells. To confirm the selectivity of this compound, it was evaluated against a panel of tyrosine kinase enzymes. Mechanistically, it successfully and selectively inhibited HDAC6, HDAC8, and EGFR with IC50 = 0.41 ± 0.015, 0.61 ± 0.027, and 0.09 ± 0.004 µM, respectively. Furthermore, the selected derivative induced apoptosis via the mitochondrial apoptotic pathway by raising the Bax/Bcl-2 ratio and activating caspases 3, 7, and 9. Also, the flow cytometry analysis of RPMI-8226 cells showed that the trimethoxy-substituted analog produced cell cycle arrest in the G1 and S phases at 55.82%. Finally, an in silico study was performed to explore the binding interaction of the most active compound within the zinc-containing binding site of HDAC6 and HDAC8.

New pyrazolo[3,4-d]pyrimidine derivatives as EGFR-TK inhibitors: design, green synthesis, potential anti-proliferative activity and P-glycoprotein inhibition.

In this study, four series of new pyrazolo[3,4-d]pyrimidine derivatives were designed and synthesized with both green and conventional methods. All the synthesized candidates were chemically confirmed using spectroscopic methods, and the DFT of the reaction mechanism was illustrated. The anti-proliferative activity of the synthesized compounds was evaluated against NCI 60 cancer cell lines. Two compounds (15 & 16) exhibited excellent broad-spectrum cytotoxic activity in NCI 5-log dose assays against the full 60-cell panel with GI50 values ranging from 0.018 to 9.98 µM. Moreover, the enzymatic assessment of the most active derivatives 4, 15, and 16 against EGFR tyrosine kinase showed significant inhibitory activities with IC50 of 0.054, 0.135, and 0.034 µM, respectively. The quantitative real-time PCR for the P-glycoprotein effect of compounds 15 and 16 was examined and illustrated the ability to inhibit the P-glycoprotein by 0.301 and 0.449 fold in comparison to the control. Mechanistic study using reversal activity in MDA-MB-468 cell line revealed the effect of both compounds 15 and 16 cytotoxicity against DOX/MDA-MB-468 with IC50 = 0.267 and 0.844 µM, respectively. Additionally, compound 16 was found to induce cell cycle arrest at the S phase with a subsequent increase in pre-G cell population in MDA-MB-468 cell line. It also increased the percentage of apoptotic cells in a time-dependent manner. Moreover, a molecular docking study was carried out to explain the target compounds' potent inhibitory activity within the EGFR binding site.

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.

Insights into fourth generation selective inhibitors of (C797S) EGFR mutation combating non-small cell lung cancer resistance: a critical review.

Lung cancer is the second most common cause of morbidity and mortality among cancer types worldwide, with non-small cell lung cancer (NSCLC) representing the majority of most cases. Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR TKIs) are among the most commonly used targeted therapy to treat NSCLC. Recent years have seen the evaluation of many synthetic EGFR TKIs, most of which showed therapeutic activity in pertinent models and were classified as first, second, and third-generation. The latest studies have concluded that their efficacy was also compromised by additional acquired mutations, including C797S. Because second- and third-generation EGFR TKIs are irreversible inhibitors, they are ineffective against C797S containing EGFR triple mutations (Del19/T790M/C797S and L858R/T790M/C797S). Therefore, there is an urgent unmet medical need to develop next-generation EGFR TKIs that selectively inhibit EGFR triple mutations via a non-irreversible mechanism. This review covers the fourth-generation EGFR-TKIs' most recent design with their essential binding interactions, the clinical difficulties, and the potential outcomes of treating patients with EGFR mutation C797S resistant to third-generation EGFR-TKIs was also discussed. Moreover, the utilization of various therapeutic strategies, including multi-targeting drugs and combination therapies, has also been reviewed.

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.

Annulated pyrazole derivatives as a novel class of urokinase (uPA) inhibitors: Green synthesis, anticancer activity, DNA-damage evaluation, and molecular modelling study.

Different series of annulated pyrazole derivatives were designed, synthesized via both green and traditional methods, and structurally characterized. In vitro uPA evaluation, antiproliferative activities and DNA binding damage was studied in this work. Thus, all the synthesized compounds were evaluated against three types of cancer cell lines; HepG-2, HCT-116, and MCF-7 cancer cell lines in addition to normal cell line WI38. Compounds 11, 20, 21, 23 and 24 displayed the most significant antiproliferative activity with IC50 ranging between 4.42 ± 0.59 µM to 11.05 ± 0.95 µM against HepG-2, HCT-116, and MCF-7 cancer cell lines compared to the reference drug, doxorubicin. Thus compound 11 exhibited cytotoxic activity with IC50 8.58 µM, 9.22 µM and 7.53 µM, compound 20 showed IC50 9.99 µM, 6.72 µM and 6.87 µM, analogue 21 displayed IC50 10.80 µM, 7.90 µM and 9.16 µM, compound 23 showed IC50 4.82 µM, 11.05 µM and 4.42 µM and derivative 24 exhibited potent cytotoxic activity with IC50 7.44 µM, 5.18 µM and 8.22 µM against HepG-2, HCT-116, and MCF-7 cancer cell lines, respectively. Additionally, compounds 11, 21, 23 and 24 showed significant uPA inhibitory activity with IC50 27.28 µM, 29.36 µM, 11.73 µM, and 7.96 µM respectively. Moreover, HCT-116 cell lines were treated with both compounds 23 and 24 that remarkably showed a high score of DNA binding damage. Mechanistic studies demonstrated the apoptotic activity of the most active tricyclic heteroaromatic analogue 24 on HCT-116 cancer cells by inducing a strong S phase cell cycle arrest suggesting that the mechanism of its antiproliferative activity may be through uPA inhibition. Finally, deeper insight illustrated that the hit compounds exhibited characteristic binding interactions in the active site of uPA that are required in the S pocket, which are important for activity Arg 217, Gly 219, and Ser 190.

Synthesis, antiproliferative activity, and molecular modeling of novel 4-methylcoumarin derivatives and/or nitric oxide donor hybrids.

Two new 4-methylcoumarin derivatives (3a-f and 4a-f) were designed, synthesized, and evaluated for their cytotoxic activity. Different spectroscopic methods and elemental analyses confirmed all the synthesized derivatives' characterization. All the prepared compounds were biologically screened against four cancer cell lines (hepatocellular carcinoma HepG-2, colon cancer cell lines HCT-116, breast cancer cell lines MCF-7, and prostate cancer cell lines PC3). The in vitro antiproliferative activity of the target analogues 4b, 4c, 4f, 3b, and 3d against the MCF-7 cancer cell line was significant, with IC50 values of 3.98, 7.80, 10.94, 17.7, and 24.07 µM, respectively. Furthermore, the potent cytotoxic oxime derivative 4b was evaluated for cell cycle analysis showing a significant substantial disruption in cell cycle profile and cell cycle arrest at the S phase boundary with a time-dependent rise in a pre-G cell population, as well as a 22-fold increase in MCF-7 apoptosis compared to control cells. Accordingly, the Bax/Bcl-2 ratio, a critical ratio in controlling cell sensitivity to apoptosis, increased upon treatment with the oxime analog 4b. A docking investigation was conducted within the BcL-2 binding site to explore and anticipate the binding modes of the synthesized compounds. Thus, synthesizing these novel coumarin/nitric oxide hybrids may aid in developing promising antiproliferative agents.

Novel 1,3-diaryl pyrazole derivatives bearing methylsulfonyl moiety: Design, synthesis, molecular docking and dynamics, with dual activities as anti-inflammatory and anticancer agents through selectively targeting COX-2.

Three series of novel 1-aryl-3-(4-methylsulfonylphenyl) pyrazole derivatives were synthesized, characterized by several spectroscopic techniques, and investigated as potential anti-inflammatory and anticancer agents. The biological evaluation showed that almost all the synthesized compounds have significant potency and selectivity for the COX-2 enzyme over COX-1 with noticeable anti-inflammatory activity compared to celecoxib and indomethacin. Accordingly, compounds 8a, 8b, 8e, 8j, 8l, 9a, 9b, 9c, and 10b showed the best COX-2 inhibition (IC50 ranged from 0.059 to 0.079 µM) with good anti-inflammatory activity (% of edema inhibition ranged from 87.9 to 67.5). Moreover, compound 8b possessed the highest selectivity index regarding COX-2 isozyme (SI = 211) in comparison to celecoxib (SI = 312) with good in vivo anti-inflammatory activity (% edema inhibition = 77.70 after 5 h). Also, compounds 8a, 8b, 8j, 8l, and 9a showed ulcerogenic liability and histopathological changes close to celecoxib. Molecular docking and dynamics simulations were also conducted to illustrate the binding modes inside the COX-2 active site. Furthermore, all compounds were screened against three cancer cell line panels to determine their antiproliferative properties by MTT assay. Compounds 8a, 8b, and 8e along with their cyclized forms 9a, 9b, and 9c exhibited a considerable antiproliferative effect on liver (IC50: 6.81-19.71 µM), colon (IC50: 7.64-15.34 µM), and breast (IC50: 6.77-18.41 µM) cancer cell lines. More importantly, compounds 8a, 8e, 9a, and 9b were found to be safe on normal HEK-293T kidney cells in comparison to cancer. cells, especially compound 8e with IC50 value of 66.45 µM. Mechanistic studies demonstrated the apoptotic activity of the most active compounds 8a, 8e, 9a, and 9b on MCF-7 cancer cells by inducing a strong S phase cell cycle arrest suggesting that the mechanism of its antiproliferative activity may be through COX-2 inhibition. Finally, the hit compounds 8a, 8b and 9a were discovered to have selective COX-2 inhibitory activity and good anti-inflammatory activity with minimal ulcerogenic effect as well as potent anticancer activity.

Garcinia cambogia Phenolics as Potent Anti-COVID-19 Agents: Phytochemical Profiling, Biological Activities, and Molecular Docking.

COVID-19 is a disease caused by the coronavirus SARS-CoV-2 and became a pandemic in a critically short time. Phenolic secondary metabolites attracted much attention from the pharmaceutical industries for their easily accessible natural sources and proven antiviral activity. In our mission, a metabolomics study of the Garcinia cambogia Roxb. fruit rind was performed using LC-HRESIMS to investigate its chemical profile, especially the polar aspects, followed by a detailed phytochemical analysis, which led to the isolation of eight known compounds. Using spectrometric techniques, the isolated compounds were identified as quercetin, amentoflavone, vitexin, rutin, naringin, catechin, p-coumaric, and gallic acids. The antiviral activities of the isolated compounds were investigated using two assays; the 3CL-Mpro enzyme showed that naringin had a potent effect with IC50 16.62 µg/mL, followed by catechin and gallic acid (IC50 26.2, 30.35 µg/mL, respectively), while the direct antiviral inhibition effect of naringin confirmed the potency with an EC50 of 0.0169 µM. To show the molecular interaction, in situ molecular docking was carried out using a COVID-19 protease enzyme. Both biological effects and docking studies showed the hydrophobic interactions with Gln 189 or Glu 166, per the predicated binding pose of the isolated naringin.

Partial Synthetic PPARƳ Derivative Ameliorates Aorta Injury in Experimental Diabetic Rats Mediated by Activation of miR-126-5p Pi3k/AKT/PDK 1/mTOR Expression.

Type 2 diabetes mellitus (T2D) is a world wild health care issue marked by insulin resistance, a risk factor for the metabolic disorder that exaggerates endothelial dysfunction, increasing the risk of cardiovascular complications. Peroxisome proliferator-activated receptor PPAR) agonists have therapeutically mitigated hyperlipidemia and hyperglycemia in T2D patients. Therefore, we aimed to experimentally investigate the efficacy of newly designed synthetic PPARα/Ƴ partial agonists on a High-Fat Diet (HFD)/streptozotocin (STZ)-induced T2D. Female Wistar rats (200 ± 25 g body weight) were divided into four groups. The experimental groups were fed the HFD for three consecutive weeks before STZ injection (45 mg/kg/i.p) to induce T2D. Standard reference PPARƳ agonist pioglitazone and the partial synthetic PPARƳ (PIO; 20 mg/kg/BW, orally) were administered orally for 2 weeks after 72 h of STZ injection. The aorta tissue was isolated for biological ELISA, qRT-PCR, and Western blotting investigations for vascular inflammatory endothelial mediators endothelin-1 (ET-1), intracellular adhesion molecule 1 (ICAM-1), E-selectin, and anti-inflammatory vasoactive intestinal polypeptide (VIP), as well as microRNA126-5p and p-AKT/p-Pi3k/p-PDK-1/p-mTOR, endothelial Nitric Oxide Synthase (eNOS) immunohistochemical staining all are coupled with and histopathological examination. Our results revealed that HFD/STZ-induced T2D increased fasting blood glucose, ET-1, ICAM-1, E-selectin, and VIP levels, while decreasing the expression of both microRNA126-5p and p-AKT/p-Pi3k/p-PDK-1/p-mTOR phosphorylation. In contrast, the partial synthetic PPARƳ derivative evidenced a vascular alteration significantly more than reference PIO via decreasing (ET-1), ICAM-1, E-selectin, and VIP, along with increased expression of microRNA126-5p and p-AKT/p-Pi3k/p-PDK-1/p-mTOR. In conclusion, the partial synthetic PPARƳ derivative significantly affected HFD/STZ-induced T2D with vascular complications in the rat aorta.

Radiolabeling, biological distribution, docking and ADME studies of 99mTc-Ros as a promising natural tumor tracer.

Rosmarinic acid (Ros) is one of phenolic metabolites with powerful potency as an anticancer agent, with different mechanisms to diminish the cancer cells. This current study represents radiolabeling of Ros with 99mTc using SnCl2 in pH4 for 15 min at 60 °C, The yield up to 92.2%. Biological evaluation in normal and cancer mice revealed the localization of the tracer in tumor tissue. Furthermore, docking and ADME (Absorption, Distribution, Metabolism, and Excretion) studies were performed, The resulted data clarifies the use of Ros as a promissing natural tracer.

Pioglitazone Synthetic Analogue Ameliorates Streptozotocin-Induced Diabetes Mellitus through Modulation of ACE 2/Angiotensin 1-7 via PI3K/AKT/mTOR Signaling Pathway.

The renin angiotensin aldosterone system has a localized key regulatory action, especially in liver and body circulation. Furthermore, it accomplishes a significant role in the downregulation of the PI3K/AKT/mTOR signaling pathway that is involved in type II diabetes mellitus pathogenesis. The current study aimed to evaluate the effect of a synthetic pioglitazone analogue (benzenesulfonamide derivative) compared to the standard pioglitazone hypoglycemic drug on enhancing liver insulin sensitivity via ACE 2/Ang (1-7)/PI3K/AKT/mTOR in experimental STZ-induced diabetes. After the model was established, rats were distributed into the normal control group, diabetic group, pioglitazone group (20 mg/kg), and a benzenesulfonamide derivative group (20 mg/kg), with the last 2 groups receiving oral treatment for 14 consecutive days. Our results suggested enhancing liver insulin sensitivity against the ACE2/Ang (1-7)/PI3K/AKT/mTOR pathway. Moreover, the synthetic compound produced a reduction in blood glucose levels, restored hyperinsulinemia back to normal, and enhanced liver glycogen deposition. In addition, it up regulated the ACE2/Ang (1-7)/PI3K/AKT/mTOR signaling pathway via increasing insulin receptor substrate 1 and 2 sensitivity to insulin, while it increased glucose transporter 2 expression in the rat pancreas. The study findings imply that the hypoglycemic effect of the benzenesulfonamide derivative is due to enhancing liver sensitivity to regulate blood glucose level via the ACE2/Ang (1-7)/PI3K/AKT/mTOR pathway.

Development and Greenness Assessment of HPLC Method for Studying the Pharmacokinetics of Co-Administered Metformin and Papaya Extract.

Foods with medical value have been proven to be beneficial, and they are extensively employed since they integrate two essential elements: food and medication. Accordingly, diabetic patients can benefit from papaya because the fruit is low in sugar and high in antioxidants. An RP-HPLC method was designed for studying the pharmacokinetics of metformin (MET) when concurrently administered with papaya extract. A mobile phase of 0.5 mM of KH2PO4 solution and methanol (65:35, v/v), pH = 5 ± 0.2 using aqueous phosphoric acid and NaOH, and guaifenesin (GUF) were used as an internal standard. To perform non-compartmental pharmacokinetic analysis, the Pharmacokinetic program (PK Solver) was used. The method's greenness was analyzed using two tools: the Analytical GREEnness calculator and the RGB additive color model. Taking papaya with MET improved the rate of absorption substantially (time for reaching maximum concentration (Tmax) significantly decreased by 75% while maximum plasma concentration (Cmax) increased by 7.33%). The extent of absorption reduced by 22.90%. Furthermore, the amount of medication distributed increased (30.83 L for MET concurrently used with papaya extract versus 24.25 L for MET used alone) and the clearance rate rose by roughly 13.50%. The results of the greenness assessment indicated that the method is environmentally friendly. Taking papaya with MET changed the pharmacokinetics of the drug dramatically. Hence, this combination will be particularly effective in maintaining quick blood glucose control.

The Red Sea marine sponge Spongia irregularis: metabolomic profiling and cytotoxic potential supported by in silico studies.

The current study discusses the chemical composition of the marine sponge Spongia irregularis using LC-HRESIMS. The metabolomic profiling resulted in the annotation of 17 metabolites of different chemical classes. Additionally, evaluation of the cytotoxic activities of the total extract and different fractions were carried out against three different cell lines where the n-butanol fraction exhibited the highest cytotoxic effects against HepG-2, MCF-7 and CACO-2 cell lines with IC50 values of 9.6 ± 0.02, 4.3 ± 0.10 and 5.6 ± 0.03 µg/mL, respectively. Also, the study was supported by docking study of the identified compounds for binding affinity to MSK1.

Natural metabolites from the soft coral Nephthea sp. as potential SARS-CoV-2 main protease inhibitors.

The ongoing spread of SARS-CoV-2 has created a growing need to develop effective antiviral treatments; therefore, this work was undertaken to delve into the natural metabolites of the Red Sea soft coral Nephthea sp. (family Nephtheidae) as a source of potential anti-COVID-19 agents. Overall, a total of 14 structurally diverse minor constituents were isolated and identified from the petroleum ether fraction of Nephthea sp. The characterised compounds were screened and compared for their inhibitory potential against SARS-CoV-2 main protease (Mpro) using Autodock Vina and MOE software. Interestingly, most compounds were able to bind effectively to the active site of Mpro, of which nephthoside monoacetate (1); an acylated tetraprenyltoluquinol glycoside, exhibited the highest binding capacity in both software with comparable interaction energies to the ligand N3 and moderately acceptable drug-likeness properties, which drew attention to the relevance of marine-derived metabolites from Nephthea sp., particularly compound (1), to develop potential SARS-CoV-2 protease inhibitors.

Lipophilicity study of different cephalosporins: Computational prediction of minimum inhibitory concentration using salting-out chromatography.

The chromatographic and lipophilicity characters of seven cephalosporins of different four classes (cephradine, cefaclor, cefprozil, cefixime, cefotaxime, ceftazidime and cefepime) were examined by salting out thin-layer chromatography (SOTLC). SOTLC using ammonium sulfate salt was employed to predict the lipophilicity of the proposed drugs via their retention behavior. The calculated RM0 values showed liner relationship with the molar concentration of ammonium sulfate in mobile phase in the range of 0.5-2.5 mol/L. Additionally, quantitative structure retention relationship (QSRR) was generated to figure out the relationship between the calculated chromatographic parameters (RM0 and C0) and log P of the studied cephalosporins. Good correlations were found between the chromatographically obtained retention parameters (RM0 and C0) and some molecular descriptors of the examined drugs. Furthermore, an efficient QSAR model was carried out using the calculated chromatographic parameters (RM0 and C0) and log P of the studied cephalosporins to predict minimum inhibitory concentration (MIC) and blood brain barrier (BBB) penetration of the examined drugs. The study was extended to separate and quantify the selected antibiotics in their pure forms and pharmaceutical formulations. Normal phase thin layer chromatographic (NP-TLC) method using a usable developing system of acetone: methanol: water: ammonium hydroxide: glacial acetic acid (90: 10: 18: 3: 2, by volume) was successfully applied to resolve the studied cephalosporins. Linearity was achieved in the range of 0.2-3 µg/mL for most of the studied antibiotics. The developed SOTLC method can be considered as a good start alternative to reversed phase thin layer chromatography (RP-TLC) for prediction of the lipophilic properties of examined cephalosporins. Moreover, the proposed NP-TLC densitometric method can be easily applied for quality control analysis of the chosen drugs and other structurally related components.

Design, microwave assisted synthesis, and molecular modeling study of some new 1,3,4-thiadiazole derivatives as potent anticancer agents and potential VEGFR-2 inhibitors.

A green and efficient method was developed for the synthesis of 1,3,4-thiadiazole based compounds under microwave (MW) activation. The nucleophile N-(5-amino-1,3,4-thiadiazol-2-yl)thiophene-2-carboxamide (3) was synthesized and reacted with different carbon electrophilic reagents to afford thiadiazolo-pyrimidine or imidazolo-thiadiazoline derivatives (4-6 and 8), respectively. Furthermore, a one-pot reaction of 3 with p-chlorobenzaldehyde and different carbon electrophile/ or nucleophiles under microwave irradiation yields the cyclic thiadiazolo-pyrimidine derivatives 10-15. Additionally, nucleophilic substitution of aromatic amines and/or potassium salts of some heterocyclic compounds with chloroacetamido-thiadiazole 6 yields derivatives 16-20. All the new derivatives were synthesized by both conventional and MW irradiation methods. All the new 1,3,4-thiadiazole derivatives were evaluated against four cancer cell lines, HepG-2, MCF-7, HCT-116, and PC-3. The anti-proliferative activity of most of the synthesized compounds exhibited excellent broad-spectrum cytotoxic activity against the cancer cell lines with IC50 values ranging from 3.97 to 9.62 µM. Moreover, the enzymatic assessment of five derivatives (2,4b, 6, 8, 9a) against VEGFR-2 tyrosine kinase showed significant inhibitory activities with IC50 of 11.5, 8.2, 10.3, 10.5 and 9.4 nM respectively. Further studies revealed the ability of compound 9a to have a strong DNA-binding affinity of 36.06 µM via DNA/methyl green assay. Moreover, molecular docking study was carried out to reveal the binding interactions of compounds in the binding site of VEGFR-2 enzyme explaining the significant inhibitory activity of these derivatives. Finally, ADME/Tox studies was performed to predict the pharmacokinetics of the synthesized compounds.

Holospiniferoside: A New Antitumor Cerebroside from The Red Sea Cucumber Holothuria spinifera: In Vitro and In Silico Studies.

Chemical investigation of the methanolic extract of the Red Sea cucumber Holothuria spinifera led to the isolation of a new cerebroside, holospiniferoside (1), together with thymidine (2), methyl-α-d-glucopyranoside (3), a new triacylglycerol (4), and cholesterol (5). Their chemical structures were established by NMR and mass spectrometric analysis, including gas chromatography-mass spectrometry (GC-MS) and high-resolution mass spectrometry (HRMS). All the isolated compounds are reported in this species for the first time. Moreover, compound 1 exhibited promising in vitro antiproliferative effect on the human breast cancer cell line (MCF-7) with IC50 of 20.6 µM compared to the IC50 of 15.3 µM for the drug cisplatin. To predict the possible mechanism underlying the cytotoxicity of compound 1, a docking study was performed to elucidate its binding interactions with the active site of the protein Mdm2-p53. Compound 1 displayed an apoptotic activity via strong interaction with the active site of the target protein. This study highlights the importance of marine natural products in the design of new anticancer agents.

Ligand-based design, molecular dynamics and ADMET studies of suggested SARS-CoV-2 Mpro inhibitors.

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has been the choice of recent studies worldwide to control its pandemic. Given the similarity with the earlier SARS-CoV, it is possible to use the previously reported inhibitors to develop a new treatment for the current attack of SARS-CoV-2. This study used the formerly published SARS-CoV Mpro small-molecule protease inhibitors to develop a pharmacophore model in order to design new ligands. Several strategies and scaffolds were evaluated in silico giving rise to ten newly designed compounds. Molecular docking and dynamics simulations were performed on Mpro enzyme in its active site to evaluate the newly designed ligands I-X. The results obtained from this work showed that compounds III-VI had a better molecular docking score than the co-crystallized ligand baicalein (3WL) giving -5.99, -5.94, -6.31, -6.56 and -5.74 kcal mol-1, respectively. Moreover, they could bind to the Mpro binding site better than I, II and VII-X. The most promising chromen-2-one based compounds V-VI had sufficiently acceptable physicochemical and ADMET properties to be considered new leads for further investigations. This new understanding should help to improve predictions of the impact of new treatments on COVID-19.