Synthesis,anticancer activity,and molecular docking of new pyrazolo[1,5-a]pyrimidine derivatives

The reaction of 3-aminopyrzoles with dimethylamino-acrylonitrile derivatives was utilized for the production of new functionalized pyrazolopyrimidine compounds 4a-c and 6a-c. The structures of the obtained pyrazolopyrimidines were characterized by the different spectroscopic measurements (IR, NMR, and mass analyses). The DFT quantum chemical calculations were applied to the determination of the HOMO-LUMO energies and Mulliken atomic charges. The investigated derivatives exhibited a low HOMO-LUMO energy gap, ranging from 2.70 to 2.34 eV, 4c and both 4b and 6b, respectively. Furthermore, the anticancer activities of the synthesized compounds have also been investigated against four cancer cells as well as normal cells (WI38). The investigated compounds demonstrated an impressive cytotoxic effect on MCF-7 and Hep-2 cells. On comparison with 5-fluorouracil, pyrazolopyrimidines 6a–c showed promising cytotoxic action against MCF-7 and Hep-2, with IC₅₀ values of 18.31–26.51 and 24.15–27.16 μM, respectively. Molecular docking of the prepared pyrazolopyrimidines 4 and 6 with the crystal structure of the KDM5A protein, obtained from the PDB, revealed the types of the protein's binding sites.     

Synthesis and evaluation of nitrate derivatives of colchicine as anticancer agents

To search for more potent antitumor agent,a series of novel nitric oxide-donating colchicine(Col) derivatives(6a-f,8a and b) were synthesized by coupling nitrates with N-methyl colchiceinamide.Their cytotoxicity against four human cancer cell lines in vitro were evaluated by MTT assay.It was found that many of the derivatives displayed significant activity,particularly,compounds 6c,8a and 8b showed more potent cytotoxic activities than Col.     

Synthesis,modeling, and biological studies of new thiazole-pyrazole analogues as anticancer agents

A series of various substituted thiazole-pyrazole hybrids 5, 7, 8, and 9 were synthesized, and their chemical structures were confirmed by spectral data (infrared, ¹H & ¹³C NMR and Mass). The frontier molecular orbital structural and energetic properties of the targeting thiazole-pyrazole hybrids were explored using the DFT/B3LYP methodology. The data indicated that they had a low energy gap (ΔE_H-L), 1.51–2.42 eV, and may be sorted as 6 < 9 < 7 < 8 < 4 < 3 < 5. The synthesized thiazole-pyrazole hybrids were explored for their activities towards HepG2, MCF-7, and HCT-116 in contrast to doxorubicin. The newly synthesized thiazole-pyrazole analogues demonstrated an acceptable efficiency towards the HepG2 cancer cell line in accordance with this order: 8 > 9 > 7 > 6. Meanwhile, most of the synthesized analogues displayed a significant reduction for the activity of the CAIX inhibitor, with IC₅₀ = 0.071 ± 0.015 to 0.902 ± 0.043 µM. Likewise, they revealed an IC₅₀ = 0.119 ± 0.043 to 0.906 ± 0.04 µM for CAXII inhibitor. Moreover, the newly synthesized thiazole-pyrazole analogues were exposed to the theoretical molecular docking study with PDB:1RHJ as the crystal structure of caspase-3 to examine their antiapoptotic effect as well as their certain properties on the caspase-3 enzyme.     

Synthesis and biological evaluation of nitric oxide-releasing sixalkoxyl biphenyl derivatives as anticancer agents

A series of novel nitric oxide-donating sixalkoxyl biphenyl derivatives （14a-1） were synthesized by coupling furoxan with alkoxyl biphenyl skeleton using amino acids as the spacers, and their cytotoxicity against HepG2 cells in vitro were evaluated by MTT method. It was found that 14c, 14d, 14f, 14i, 14j and 14k showed more potent cytotoxic activities than control 5-fluorouracil. NO release assay of target compounds indicated that the maximum amount of NO released by most active compounds 14c and 14j was about 6 × 10^-2 μmol/L, whereas 14a and 14h with very weak activity only released NO of 1 × 10^-2 μmol/L.     

Synthesis,characterization, anticancer activity,and molecular docking of some new sugar hydrazone and arylidene derivatives

New sugar hydrazone moieties, their oxadiazoline derivatives, and arylidene analogues were prepared and chemically elucidated using spectroscopic analysis, such as nuclear magnetic resonance, for hydrogen ¹HNMR, carbon ¹³CNMR, elemental analysis, and Infrared (IR). The prepared compounds were purified and tested against breast cancer cells (MCF-7). Compounds 4c, 4d, 6b, and 6d exhibited moderate to very high anti-breast cancer activity, with a percentage of inhibition of 96.19%, 93.08%, 74.33%, and 86.05% respectively; the reference 5-fluorouracil had an inhibitory percentage of 96.02%.     

含1,3,4-噁二唑的喹啉衍生物的合成、抗AChE活性及分子对接研究

为研发新型乙酰胆碱酯酶抑制剂,本文通过碘介导环化反应合成了一系列含1,3,4-噁二唑的喹啉衍生物,并通过熔点和核磁共振确定了其结构。在1 μmol/mL浓度下,对这些衍生物抗乙酰胆碱酯酶活性进行了初步的生物测定。结果表明,化合物4b和4j具有中等的抑制活性,抑制率分别为79.18%和78.46%。初步的构效关系表明,在目标化合物的1,3,4-噁二唑环上引入杂环可以其提高其活性。分子对接研究表明,化合物4b和4j和乙酰胆碱酯酶的催化活性中心部位显著结合。     

Molecular modeling and docking studies of new antimicrobial antipyrine-thiazole hybrids

A series of new antipyrine incorporated thiazole derivatives having phenoxyacetamide moiety as a link bridge was synthesized. The synthetic strategy involves condensation of the precursor N-(4-antipyrinyl)-2-(4-formylphenoxy)acetamide with thiosemicarbazide followed by heterocyclization of the produced thiosemicarbazone with various α-halogenated carbonyl compounds (namely; 4-chlorophenacyl bromide, ethyl bromoacetate, 3-chloroacetylacetone and ethyl 4-chloroacetoacetate). Moreover, the quantum chemical calculations at DFT/B3LYP level were used to determine the HOMO-LUMO energies and Fukui’s indices toward nucleophilic, electrophilic and radical attacks. The investigated compounds were arranged due to HOMO-LUMO energy gap as following 6 < 5 < 7 < 3 < 2 < 4 < 8. The synthesized antipyrinyl-thiazole hybrids were screened to evaluate their antibacterial and antifungal efficacies. Using Chloramphenicol as reference material, the synthesized antipyrinyl-thiazole hybrids were revealed a remarkable activity against S. aureus than B. subtilis, as example for Gram’s positive strains. The antipyrine-thiazole compounds 3, 4, 6 and 8 exhibited significant MIC values. However, the antipyrine-thiazole hybride 4 displayed reputable activities against Gram’s negative strains S. typhimurium and E. coli, respectively, in comparison with Cephalothin. Likewise, the compounds 7 and 8 were demonstrated respectable antifungal efficacy toward C. albicans in contrast to cycloheximide grade. The theoretical molecular docking studies were applied to simulate reactivity of the synthesized antipyrine-thiazole hybrids against contrasting binding sites for both of Staphylococcus aureus “Homo sapiens” (pdb: 3HUN) protein and E.coli “Homo sapiens” (PDB: 2EXB) protein. The theoretical and practical antibacterial and antifungal activities result in this work designated a proper agreement.     

Synthesis and cytotoxicity screening of derivatives of the simplified ecteinascidin pentacyclic skeleton as anticancer agents

A series of new ecteinascidin pentacyclic-derived compounds bearing aryl carboxylic amide side chains at C-22 have been designed and synthesized. The cytotoxicity evaluation confirmed their potent antitumor activity by use of eight different cell lines. Studies on the structure-activity relationship of them showed that the chemical structure of C-22 pendants have great effects on the tumor-killing activity. Notably, Compounds 6, 7 and 8 with benzo[b]thiophene-2-carboxamide pendants exhibited excellent broad-spectrum antitumor activity with the low IC₅₀ values of 10^?7?M.     

1,3-Oxazole derivatives of cytisine as potential inhibitors of glutathione reductase of Candida spp.: QSAR modeling,docking analysis and experimental study of new anti-Candida agents

Natural products as well as their derivatives play a significant role in the discovery of new biologically active compounds in the different areas of our life especially in the field of medicine. The synthesis of compounds produced from natural products including cytisine is one approach for the wider use of natural substances in the development of new drugs. QSAR modeling was used to predict and select of biologically active cytisine-containing 1,3-oxazoles. The eleven most promising compounds were identified, synthesized and tested. The activity of the synthesized compounds was evaluated using the disc diffusion method against C. albicans M 885 (ATCC 10,231) strain and clinical fluconazole-resistant Candida krusei strain. Molecular docking of the most active compounds as potential inhibitors of the Candida spp. glutathione reductase was performed using the AutoDock Vina. The built classification models demonstrated good stability, robustness and predictive power. The eleven cytisine-containing 1,3-oxazoles were synthesized and their activity against Candida spp. was evaluated. Compounds 10, 11 as potential inhibitors of the Candida spp. glutathione reductase demonstrated the high activity against C. albicans M 885 (ATCC 10,231) strain and clinical fluconazole-resistant Candida krusei strain. The studied compounds 10, 11 present the interesting scaffold for further investigation as potential inhibitors of the Candida spp. glutathione reductase with the promising antifungal properties. The developed models are publicly available online at http://ochem.eu/article/120720 and could be used by scientists for design of new more effective drugs.     

Quantum computational,spectroscopic and molecular docking studies on 6-amino-3-bromo-2-methylpyridine

In order to confirm the vibrational assignments, the density functional hypothesis has been used for 6-amino-3-bromo-2-methylpyridine (6A3B2MP). The entire energy distribution is used to materialize the several vibrational modes of 6A3B2MP (TED). The DFT/B3LYP approach is used to examine the molecular optimum limits and electronic characteristics of 6A3B2MP. Investigations have been made into the molecular orbital, Fukui function analysis, natural bond orbital (NBO), and molecular electrostatic potential (MEP) characteristics of 6A3B2MP. Theoretical studies have focused on the UV–vis spectra with different solvents. According to the outcomes of the molecular docking technique, the 6A3B2MP is docked with two target proteins, which is crucial for the emergence of cancer. Therefore, this research paves the door for the development of medicines that are specially formulated.     

Molecular docking studies of some new imidazole derivatives for antimicrobial properties

In modern drug designing, molecular docking is routinely used for understanding drug-receptor interaction. In the present study six imidazole derivatives containing substituted pyrazole moiety (2a,b and 4a–d) were synthesized. Structures of the newly synthesized compounds were characterized by spectral studies. Compounds were screened for their antibacterial activity. Compound 4c was found to be potent antimicrobial against Pseudomonas aeruginosa at concentrations of 1 and 0.5 mg/mL compared to standard drug Streptomycin. All the compounds were subjected to molecular docking studies for the inhibition of the enzyme l-glutamine: d-fructose-6-phosphate amidotransferase[GlcN-6-P] (EC 2.6.1.16). The in silico molecular docking study results showed that, all the synthesized compounds having minimum binding energy and have good affinity toward the active pocket, thus, they may be considered as good inhibitor of GlcN-6-P synthase.     

Novel imidazole derivatives as antifungal agents: Synthesis,biological evaluation,ADME prediction and molecular docking studies

Abstract

A series of 2-(substituteddithiocarbamoyl)-N-[4-((1H-imidazol-1-yl)methyl)phenyl]acetamide derivatives was designed and synthesized to combat the increasing incidence of drug-resistant fungal infections. All synthesized compounds were characterized by IR, ¹H-NMR, ¹³C-NMR, and HRMS spectra and elemental analyses. Antifungal activity tests were performed against four different fungal strains. Molecular docking studies were performed to investigate the mode of action towards the fungal lanosterol 14α-demethylase, a cytochrome P450-dependent enzyme. ADME studies were carried out and a connection between activities and physicochemical properties of the target compounds was determined. Most of the final compounds exhibited significant activity against Candida albicans and Candida krusei with MIC₅₀ value 12.5?μg/mL. The results of in vitro anti-Candida activity, a docking study and ADME prediction revealed that the newly synthesized compounds have potential anti-Candida activity and evidenced the most active derivative, 5b (2-Pyrrolidinthiocarbonylthio-N-[4-((1H-imidazol-1-yl)methyl)phenyl]acetamide), which can be further optimized as a lead compound.     

Synthesis,biological evaluation and molecular docking study of dihydropyrimidine derivatives as potential anticancer agents

A series of dihydropyrimidine analogues were prepared via one-pot Biginelli three-component condensation reaction and characterized by NMR, FT-IR, MS spectra, and element analysis. Subsequently, they were screened for in vitro anticancer effect. These analogues revealed good cytotoxic activity against three human cancer cell lines including MCF-7, HepG-2, and A549. Among these analogues, compounds 4d and 4h were the most potent against three cell lines. Cell viability assays indicated 4a and 4c had lower cytotoxicity. In vitro cytotoxicity study on all synthesized compounds demonstrated that introduction of electron withdrawing substituents on C4 position of phenyl ring of dihydropyrimidine contributed to the antiproliferative potency. Moreover, in silico molecular docking results stipulated a sign of good correlation between experimental activity and calculated binding affinity. It proved 4d and 4h as the strongest compounds. Binding modes of analogues proposed the involvement of hydrophobic interactions and hydrogen bonds with Eg5 active site. Structure activity relationship studies indicated that incorporating electron withdrawing substituents on C4 position of phenyl ring of dihydropyrimidine are important for this biological activity.     

In-silico profiling,design, molecular docking computation,and drug kinetic model evaluation of novel curcumin derivatives as potential anticancer agents

The alarming trend of leukemia cell lines that are multidrug-resistant has prompted scientists to scramble for effective new anticancer treatments. Therefore, it remains an intriguing scientific task to optimize curcumin by trying to introduce molecular alteration to its vital structure to improve the biological effect against the P388 cell line or get around resistance phenomena. Regardless of the wide range of medications that are now being studied, Prednisone remains the most important and efficient part of chemotherapy that the WHO recommends. This article discusses the QSAR-oriented model and in silico assessment of some potent curcumin derivatives' anticancer activity against the P388 cell line. The solidity and propensity for prediction of the model were ensured by using stringent validation procedures. The activity of these derivatives was shown to be unrelated to lipophilicity, while shorter N-N distances and short substituents result in quite bioactive molecules. This information was used to design potent molecules that demonstrate good quality as per the assessment based on the Lead-Like Soft rule is acceptable for drug-like molecules. Also, molecule d2 does not possess any toxic effects risk alerts, suggesting drug-adherent conduct. While Prednisone the reference drug has a toxicity risk alert in red, suggesting non-adherent conduct for Prednisone. Hence, the novel molecules are promising anticancer agents.     

Synthesis and biological evaluation of novel coumarin-chalcone derivatives containing urea moiety as potential anticancer agents

The increasing interest on new drug discovery is constantly up to date as drugs do not increase survival adequately against increasing cancer cases worldwide. Based on the reported anticancer activity of coumarin, chalcone and urea derivatives, the present investigation dealt with the design and synthesis of coumarin derivatives bearing diversely substituted chalcone-urea moieties 5a-k. Through a structure-based molecular hybridization approach, a series of novel coumarin-chalcone derivatives containing urea moiety was synthesized and screened for their in vitro antiproliferative activities against the cancer cell lines (H4IIE and HepG2). In addition, the synthesized compounds were tested on a cell line that was not cancerous (CHO) and the damage, it could give to normal cells was determined. Among the synthesized compounds, 5k exhibited better inhibition of H4IIE compared to Sorafenib. 5j also showed better inhibition against HepG2 than Sorafenib. In particular, 5k induced H4IIE apoptosis, arrested cell cycle at the S phase. Therefore, 5k and 5j may be potent antitumor agents, representing a promising lead for further optimization.     

Molecular docking,dynamics simulations and 3D-QSAR modeling of arylpiperazine derivatives of 3,5-dioxo-(2H,4H)-1,2,4-triazine as 5-HT1AR agonists

Serotonin receptor, 5-HT_1AR, agonists and partial agonists have established drug candidates for psychiatric and neurologic disorders. Recently, we reported the synthesis and evaluation of arylpiperazine derivatives of 3,5-dioxo-(2H,4H)-1,2,4-triazine as 5-HT_1AR ligands. Herein, we generated a homology model of the receptor and docked the ligands against it, predicted the stability of the receptor model and complexes by molecular dynamics and generated a 3D-QSAR model for the arylpiperazine derivatives of 3,5-dioxo-(2H,4H)-1,2,4-triazine. The model suggests the hydrophobic part that arises from the aromatic region and the electron withdrawing parts play a vital role in the agonist activity of the lead molecules.     

Synthesis of functionalized carboranes as potential anticancer and BNCT agents

Carboranyl aldehydes react with alpha,beta-unsaturated esters, ketones, and nitriles in the presence of DABCO to provide functionalized carboranyl alcohols in good yields. Acetates of these alcohols undergo a facile isomerization with a variety of nucleophiles and afford structurally interesting carboranes. Biological evaluation of these molecules exhibited impressive antiproliferative activity for brain and breast cancer cells.     

Synthesis,biological evaluation and computational studies of fused acridine containing 1,2,4-triazole derivatives as anticancer agents

A novel series of fused acridine containing 1,2,4-triazole derivatives (13a-j) have been synthesized and their structures were confirmed by ¹HNMR, 13CNMR and mass spectral data. Further, all these derivatives were tested for their anticancer activity against four human cancer cell lines A549 (Lung), MCF7 (Breast), A375 (Melanoma) and HT-29 (Colon). The IC₅₀ values range of target compounds shown 0.11 ± 0.02 to 13.8 ± 0.99 µM as compared with standard drug range 0.11 ± 0.02 to 0.93 ± 0.056 µM. Among them, compounds 13d, 13f, 13g, 13h, 13i, and 13j were exhibited more potent activity. Docking simulation was performed as a trial to study the mechanisms and binding modes of these compounds towards the DNA target. The results showed these compounds have intercalated placement in the active sites and stable interactions similar to the co-crystallized reference ligand. Further, these compounds (13a-j) were investigated for Drug-likeness, ADME properties and Toxicity risk assessment.