Design, synthesis and mechanistic study of new dual targeting HDAC/tubulin inhibitors.

Aim: The purpose of this work is to create and synthesize a new class of chemicals: 3-cyano-2-substituted pyridine compounds with expected multitarget inhibition of histone deacetylase (HDAC) and tubulin. Materials & methods: The target compounds (3a-c, 4a-c and 5a-c) were synthesized utilizing 6-(4-methoxyphenyl)-2-oxo-4-(3,4,5-trimethoxyphenyl)-3-cyanopyridine, with various linkers and zinc-binding groups (ZBGs). Results: Most of the tested compounds showed promising growth inhibition, and hydroxamic acid-containing hybrids possessed higher HDAC inhibition than other ZBGs. Compound 4b possessed the highest potency; however, it showed the most tubulin polymerization inhibition. Docking studies displayed good binding into HDAC1 and six pockets and tubulin polymerization protein. Conclusion: Compound 4b could be considered a good antitumor candidate to go further into in vivo and clinical studies.

Discovery of new thiazolidine-2,4-dione derivatives as potential VEGFR-2 inhibitors: In vitro and in silico studies.

In this study, a series of seven novel 2,4-dioxothiazolidine derivatives with potential anticancer and VEGFR-2 inhibiting abilities were designed and synthesized as VEGFR-2 inhibitors. The synthesized compounds were tested in vitro for their potential to inhibit VEGFR-2 and the growth of HepG2 and MCF-7 cancer cell lines. Among the compounds tested, compound 22 (IC50 = 0.079 µM) demonstrated the highest anti-VEGFR-2 efficacy. Furthermore, it demonstrated significant anti-proliferative activities against HepG2 (IC50 = 2.04 ± 0.06 µM) and MCF-7 (IC50 = 1.21 ± 0.04 M). Additionally, compound 22 also increased the total apoptotic rate of the MCF-7 cancer cell lines with cell cycle arrest at S phase. As well, computational methods were applied to study the VEGFR-2-22 complex at the molecular level. Molecular docking and molecular dynamics (MD) simulations were used to investigate the complex's structural and kinetic characteristics. The DFT calculations further revealed the structural and electronic properties of compound 22. Finally, computational ADMET and toxicity tests were performed indicating the likeness of the proposed compounds to be drugs. The results suggest that compound 22 displays promise as an effective anticancer treatment and can serve as a model for future structural modifications and biological investigations in this field.

Novel Aminopyrimidine-2,4-diones, 2-Thiopyrimidine-4-ones, and 6-Arylpteridines as Dual-Target Inhibitors of BRD4/PLK1: Design, Synthesis, Cytotoxicity, and Computational Studies.

Structural-based drug design and solvent-free synthesis were combined to obtain three novel series of 5-arylethylidene-aminopyrimidine-2,4-diones (4, 5a-c, 6a,b), 5-arylethylidene-amino-2-thiopyrimidine-4-ones (7,8), and 6-arylpteridines (9,10) as dual BRD4 and PLK1 inhibitors. MTT assays of synthesized compounds against breast (MDA-MB-231), colorectal (HT-29), and renal (U-937) cancer cells showed excellent-to-good cytotoxic activity, compared to Methotrexate; MDA-MB-231 were the most sensitive cancer cells. The most active compounds were tested against normal Vero cells. Compounds 4 and 7 significantly inhibited BRD4 and PLK1, with IC50 values of 0.029, 0.042 µM, and 0.094, 0.02 µM, respectively, which are nearly comparable to volasertib (IC50 = 0.017 and 0.025 µM). Compound 7 triggered apoptosis and halted cell growth at the G2/M phase, similarly to volasertib. It also upregulated the BAX and caspase-3 markers while downregulating the Bcl-2 gene. Finally, active compounds fitted the volasertib binding site at BRD4 and PLK1 and showed ideal drug-like properties and pharmacokinetics, making them promising anticancer candidates.

New thiazolidine-2,4-diones as effective anti-proliferative and anti-VEGFR-2 agents: Design, synthesis, in vitro, docking, MD simulations, DFT, ADMET, and toxicity studies.

Novel thiazolidine-2,4-dione derivatives, 11a-g, were designed, and synthesized targeting the VEGFR-2 protein. The in vitro studies indicated the abilities of the synthesized derivatives to inhibit VEGFR-2 and prevent the growth of two different cancer cell types, HepG2 and MCF-7. Compound 11 f exhibited the strongest anti-VEGFR-2 activity (IC50 = 0.053 µM). As well, compound 11 f showed impressive anti-proliferative activity against the mentioned cancer cell lines with IC50 values of 0.64 ± 0.01 and 0.53 ± 0.04 µM, respectively. Additionally, compound 11 f arrested the MCF-7 cell cycle at the S phase and increased the overall apoptosis percentage. Furthermore, cell migration assay revealed that compound 11 f has a significant ability to prevent migration and healing potentialities of MCF-7. Moreover, computational studies were used to conduct the molecular investigation of the VEGFR-2-11 f complex. The kinetic and structural features of the complex were examined using molecular dynamics simulations and molecular docking. Besides, Principal component analysis (PCA) was used to explain the dynamics of the VEGFR-2-11 f complex at various spatial scales. The DFT calculations also provided further clarity regarding compound 11 f's structural and electronic features. To evaluate how closely the developed compounds might look like drugs, ADMET and toxicity experiments were computed. To conclude, the presented study demonstrates the potential of compound 11 f as a viable anti-cancer drug, which can serve as a prototype for future structural modifications and further biological investigations.

Synthesis, DFT calculations, and anti-proliferative evaluation of pyrimidine and selenadiazolopyrimidine derivatives as dual Topoisomerase II and HSP90 inhibitors.

Novel series of aminopyrimidines bearing a biologically active cyclohexenone 3a-f and oxo-selaneylidene moiety 4, besides selenadiazolopyrimidines (5a-e and 7), were synthesised using 5,6-diaminouracils as starting materials. Compound 3a exhibited strong anti-proliferative activity against three cell lines: HepG-2 (IC50 14.31 ± 0.83 µM), A-549 (IC50 30.74 ± 0.76 µM), and MCF-7 (IC50 27.14 ± 1.91 µM). Also, it was four times more selectively cytotoxic against WI-38 cell lines than doxorubicin. Furthermore, Topoisomerase II (IC50 4.48 ± 0.65 µM) and HSP90 (IC50 1.78 ± 0.11 µM) were both strongly inhibited in vitro by 3a. The cell cycle was halted at the G1-S phase, and total apoptotic cells were 65 times more than control Hep-G2 cells. Besides, it increased caspase-3 gene expression, triggering mitochondrial cell death. Molecular docking study indicated that it could bind to Topoisomerase II and HSP90 binding sites in an inhibitory mode. Its geometric properties were investigated using the density functional theory (DFT). Furthermore, compound 3a demonstrated in silico good oral bioavailability.

Design, synthesis, docking, and anticancer evaluations of new thiazolo[3,2-a] pyrimidines as topoisomerase II inhibitors.

New thiazolopyrimidine derivatives 2, 3a-d, 4a-c, 5, 6a-c, and 7a,b were synthesised. All prepared compounds were evaluated by MTT cytotoxicity assay against three human tumour cell lines. Compounds 3c, 3d, 4c, 6a, 6b, and 7b exhibited potent to strong anticancer activity that was nearly comparable or superior to Doxorubicin. Compounds exhibiting significant cytotoxicity were further selected to study their inhibitory activity on the Topo II enzyme. Compound 4c was the most potent Topo II inhibitor with an IC50 value of 0.23 ± 0.01 µM, which was 1.4-fold and 3.6-fold higher than the IC50 values of Etoposide and Doxorubicin. Furthermore, compound 4c showed significant cell cycle disruption and apoptosis on A549 cells compared to control cells. Molecular docking of the most active compounds illustrated proper fitting to the Topo II active site, suggesting that our designed compounds are promising candidates for the development of effective anticancer agents acting through Topo II inhibition.

(E)-N-(3-(1-(2-(4-(2,2,2-Trifluoroacetamido)benzoyl)hydrazono)ethyl)phenyl)nicotinamide: A Novel Pyridine Derivative for Inhibiting Vascular Endothelial Growth Factor Receptor-2: Synthesis, Computational, and Anticancer Studies.

(E)-N-(3-(1-(2-(4-(2,2,2-Trifluoroacetamido)benzoyl)hydrazono)ethyl)phenyl)nicotinamide (compound 10) was designed as an antiangiogenic VEGFR-2 inhibitor with the essential pharmacophoric structural properties to interact with the catalytic pocket of VEGFR-2. The designed derivative was synthesized, and its structure was confirmed through Ms, elemental, 1H, and 13C spectral data. The potentiality of the designed pyridine derivative to bind with and inhibit the vascular endothelial growth factor receptor-2 (VEGFR-2) enzyme was indicated by molecular docking assessments. In addition, six molecular dynamic (MD) experiments proved its correct binding with VEGFR-2 over 100 ns. Additionally, the molecular mechanics energies, combined with the generalized born and surface area (MM-GBSA) analysis, identified the precise binding with optimum energy. To explore the stability and reactivity of the designed pyridine derivative, density functional theory (DFT) calculations, including electrostatic potential maps and total electron density, were carried out. Additionally, the absorption, distribution, metabolism, excretion, and toxicity (ADMET) analysis demonstrated its general likeness and its safety. The designed compound was synthesized to evaluate its effects against VEGFR-2 protein, cancer, and normal cells. The in vitro results were concordant with the in silico results, because the new pyridine derivative (compound 10) displayed VEGFR-2 inhibition with an IC50 value of 65 nM and displayed potent cytotoxic properties against hepatic (HepG2) and breast (MCF-7) cancer cell lines with IC50 values of 21.00 and 26.10 µM, respectively; additionally, it exhibited high selectivity indices against the normal cell lines (W-38) of 1.55 and 1.25, respectively. The obtained results present compound 10 as a new lead VEGFR-2 inhibitor for further biological investigation and chemical modifications.

New Pyrimidine-5-Carbonitriles as COX-2 Inhibitors: Design, Synthesis, Anticancer Screening, Molecular Docking, and In Silico ADME Profile Studies.

Two series of cyanopyrimidine hybrids were synthesized bearing either benzo[d]imidazole, benzo[d]oxazole, benzo[d]thiazole, and benzo[b]thiophene derivatives via methylene amino linker 3a-3d (Formula A) or various sulphonamide phenyl moieties 5a-5d (Formula B) at the C-2 position. All compounds' cyclooxygenase COX-2 inhibitory activities were evaluated, and all synthesized compounds demonstrated potent activity at minimal concentrations, with IC50 values in the submicromolar range. Compounds 3b, 5b, and 5d were discovered to be the most active pyrimidine derivatives, with the highest COX-2 percent inhibition and IC50 values being nearly equal to Celecoxib and approximately 4.7-, 9.3-, and 10.5-fold higher than Nimesulide. Furthermore, the pyrimidine derivatives 3b, 5b, and 5d demonstrated anticancer activity comparable to or better than doxorubicin against four cell lines, i.e., MCF-7, A549, A498, and HepG2, with IC50 values in nanomolar in addition to low cytotoxicity on the normal W38-I cell line. The effect of compound 5d on cell cycle progression and apoptosis induction was investigated, and it was found that compound 5d could seize cell growth at the sub-G1 and G2/M phases, as well as increase the proportion of early and late apoptotic rates in MCF-7 cells by nearly 13- and 60-fold, respectively. Moreover, in silico studies for compounds 3b, 5b, and 5d revealed promising findings, such as strong GIT absorption, absence of BBB permeability, nil-to-low drug-drug interactions, good oral bioavailability, and optimal physicochemical properties, indicating their potential as promising therapeutic candidates.

Molecular iodine-promoted oxidative cyclization for the synthesis of 1,3,4-thiadiazole-fused- [1,2,4]-thiadiazole incorporating 1,4-benzodioxine moiety as potent inhibitors of α-amylase and α-glucosidase: In vitro and in silico study.

Twenty-five analogs were synthesized based on 1,3,4-thiadiazole-fused-[1,2,4]-thiadiazole incorporating 1,4-benzodioxine moiety (1-25) and then tested for the antidiabetic profile. The entire afforded derivatives showed varied inhibition profiles ranging between 0.70 ± 0.01 and 30.80 ± 0.80 µM (against α-amylase) in comparison to standard acarbose (12.80 ± 0.10 µM). Similarly, synthetics analogs also displayed a varied range of α-glucosidase activity ranging from 0.80 ± 0.01 µM to IC50 = 29.70 ± 0.40 µM (against α-glucosidase) as compared to standard acarbose (IC50 = 12.90 ± 0.10 µM). Among synthesized analogs, compound 22 showed excellent potency due to the presence of di-hydroxy substitutions at the 2,3-position of the aryl ring. For all analogs, the structure-activity relationship was carried out based on the pattern of substitutions around the aryl ring, and further, the potent analogs were subjected to a molecular docking study to analyze how active residues of targeted enzymes interact with active parts of newly prepared analogs. The result obtained shows that these compounds furnish several key interactions with enzyme active sites and, hence, enhanced their enzymatic activities.

New Triazinoindole Bearing Benzimidazole/Benzoxazole Hybrids Analogs as Potent Inhibitors of Urease: Synthesis, In Vitro Analysis and Molecular Docking Studies.

Twenty-four analogs based on triazinoindole bearing benzimidazole/benzoxazole moieties (1-25) were synthesized. Utilizing a variety of spectroscopic methods, including 1H-, 13C-NMR, and HREI-MS, the newly afforded compounds (1-25) were analyzed. The synthesized analogs were tested against urease enzyme (in vitro) as compared to the standard thiourea drug. All triazinoindole-based benzimidazole/benzoxazole analogs (1-25) exhibited moderate to excellent inhibition profiles, having IC50 values of 0.20 ± 0.01 to 36.20 ± 0.70 µM when evaluated under the positive control of thiourea as a standard drug. To better understand the structure-activity relationship, the synthesized compounds were split into two groups, "A" and "B." Among category "A" analogs, analogs 8 (bearing tri-hydroxy substitutions at the 2,4,6-position of aryl ring C) and 5 (bearing di-hydroxy substitutions at the 3,4-position of aryl ring C) emerged as the most potent inhibitors of urease enzyme and displayed many times more potency than a standard thiourea drug. Besides that, analog 22 (which holds di-hydroxy substitutions at the 2,3-position of the aryl ring) and analog 23 (bearing ortho-fluoro substitution) showed ten-fold-enhanced inhibitory potential compared to standard thiourea among category "B" analogs. Molecular docking studies on the active analogs of each category were performed; the results obtained revealed that the presence of hydroxy and fluoro-substitutions on different positions of aryl ring C play a pivotal role in binding interactions with the active site of the targeted urease enzyme.

Synthesis of Novel 2,3-Dihydro-1,5-Benzothiazepines as α-Glucosidase Inhibitors: In Vitro, In Vivo, Kinetic, SAR, Molecular Docking, and QSAR Studies.

In the present study, a series of 2,3-dihydro-1,5-benzothiazepine derivatives 1B-14B has been synthesized sand characterized by various spectroscopic techniques. The enzyme inhibitory activities of the target analogues were assessed using in vitro and in vivo mechanism-based assays. The tested compounds 1B-14B exhibited in vitro inhibitory potential against α-glucosidase with IC50 = 2.62 ± 0.16 to 10.11 ± 0.32 µM as compared to the standard drug acarbose (IC50 = 37.38 ± 1.37 µM). Kinetic studies of the most active derivatives 2B and 3B illustrated competitive inhibitions. Based on the α-glucosidase inhibitory effect, the compounds 2B, 3B, 6B, 7B, 12B, 13B, and 14B were chosen in vivo for further evaluation of antidiabetic activity in streptozotocin-induced diabetic Wistar rats. All these evaluated compounds demonstrated significant antidiabetic activity and were found to be nontoxic in nature. Moreover, the molecular docking study was performed to elucidate the binding interactions of most active analogues with the various sites of the α-glucosidase enzyme (PDB ID 3AJ7). Additionally, quantitative structure-activity relationship (QSAR) studies were performed based on the α-glucosidase inhibitory assay. The value of correlation coefficient (r) 0.9553 shows that there was a good correlation between the 1B-14B structures and selected properties. There is a correlation between the experimental and theoretical results. Thus, these novel compounds could serve as potential candidates to become leads for the development of new drugs provoking an anti-hyperglycemic effect.