Synthesis and In Silico Analysis of New Polyheterocyclic Molecules Derived from [1,4]-Benzoxazin-3-one and Their Inhibitory Effect against Pancreatic α-Amylase and Intestinal α-Glucosidase

This study focuses on synthesizing a new series of isoxazolinyl-1,2,3-triazolyl-[1,4]-benzoxazin-3-one derivatives 5a-5o. The synthesis method involves a double 1,3-dipolar cycloaddition reaction following a "click chemistry" approach, starting from the respective [1,4]-benzoxazin-3-ones. Additionally, the study aims to evaluate the antidiabetic potential of these newly synthesized compounds through in silico methods. This synthesis approach allows for the combination of three heterocyclic components: [1,4]-benzoxazin-3-one, 1,2,3-triazole, and isoxazoline, known for their diverse biological activities. The synthesis procedure involved a two-step process. Firstly, a 1,3-dipolar cycloaddition reaction was performed involving the propargylic moiety linked to the [1,4]-benzoxazin-3-one and the allylic azide. Secondly, a second cycloaddition reaction was conducted using the product from the first step, containing the allylic part and an oxime. The synthesized compounds were thoroughly characterized using spectroscopic methods, including 1H NMR, 13C NMR, DEPT-135, and IR. This molecular docking method revealed a promising antidiabetic potential of the synthesized compounds, particularly against two key diabetes-related enzymes: pancreatic α-amylase, with the two synthetic molecules 5a and 5o showing the highest affinity values of 9.2 and 9.1 kcal/mol, respectively, and intestinal α-glucosidase, with the two synthetic molecules 5n and 5e showing the highest affinity values of -9.9 and -9.6 kcal/mol, respectively. Indeed, the synthesized compounds have shown significant potential as antidiabetic agents, as indicated by molecular docking studies against the enzymes α-amylase and α-glucosidase. Additionally, ADME analyses have revealed that all the synthetic compounds examined in our study demonstrate high intestinal absorption, meet Lipinski's criteria, and fall within the required range for oral bioavailability, indicating their potential suitability for oral drug development.

In silico and in vitro prediction of new synthesized N-heterocyclic compounds as anti-SARS-CoV-2

Computer-aided drug design has been employed to get the medicinal effects against Corona virus from different pyridine derivatives after synthesizing the new compounds. Additionally, various computational studies are also employed between the newly prepared pyridine derivatives and three controls against three proteins (6Y2E, 6M71 and 6M3M). Different methods were employed to synthesize new pyridine derivatives according to the literature using different reaction mediums. MTT was performed for cytotoxicity study and IC50 for inhibitory concentration. Additionally, in-silico studies including DFT, molecular docking, molecular dynamics, MMPBSA, ADME, pharmacokinetics and Lipinski rules were evaluated. The chemical structures of all new compounds were elucidated based on spectroscopic investigation. A molecular docking study demonstrated that compounds 5, 11, and 12 have the best binders of the SARS-CoV-2 main protease enzyme, with energy scores of - 7.5 kcal/mol, - 7.2 kcal/mol, and - 7.9 kcal/mol, respectively. The net binding energy values of the 11-Mpro, 12-Mpro, and 5-Mpro complexes revealed their highly stable nature in terms of both intermolecular interactions and docked conformation across the simulation time. ADME properties, besides the pharmacokinetics and Lipinski rules, showed that all seven newly synthesized compounds follow Lipinski rules with high GI absorption. The In Vitro antiviral study against SARS-CoV-2 using MTT methods confirms that compound 5 has more potential and is safer than other tested compounds. The study shows that the newly synthesized pyridine derivatives have medicinal properties against SARS-CoV-2 without violating Lipinski rules. Compounds 5, 11, and 12, particularly compound 5, may serve as promising potential candidate for COVID-19.

Emerging Aspects of Triazole in Organic Synthesis: Exploring its Potential as a Gelator

Cu(I)-catalyzed azide-alkyne 1,3-dipolar cycloaddition (CuAAC) - commonly known as the "click reaction" - serves as the most effective and highly reliable tool for facile construction of simple to complex designs at the molecular level. It relates to the formation of carbon heteroatomic systems by joining or clicking small molecular pieces together with the help of various organic reactions such as cycloaddition, conjugate addition, ring-opening, etc. Such dynamic strategy results in the generation of triazole and its derivatives from azides and alkynes with three nitrogen atoms in the five-membered aromatic azole ring that often forms gel-assembled structures having gelating properties. These scaffolds have led to prominent applications in designing advanced soft materials, 3D printing, ion sensing, drug delivery, photonics, separation, and purification. In this review, we mainly emphasize the different mechanistic aspects of triazole formation, which includes the synthesis of sugar-based and non-sugar-based triazoles, and their gel applications reported in the literature for the past ten years, as well as the upcoming scope in different branches of applied sciences.

Recent advances in 1,2,3- and 1,2,4-triazole hybrids as antimicrobials and their SAR: A critical review

With the widespread use and sometimes even abuse of antibiotics, the problem of bacterial resistance to antibiotics has become very serious, and it is posing a great threat to global health. Therefore, development of new antibiotics is imperative. Triazoles are five-membered, nitrogen-containing aromatic heterocyclic scaffolds, with two isomeric forms, i.e. 1,2,3-triazole and 1,2,4-triazole. Triazole-containing compounds have a wide range of biological activities such as antibacterial, antifungal, anticancer, antioxidant, antitubercular, antimalarial, anti-HIV, anticonvulsant, anti-inflammatory, antiulcer, analgesic, and etc. The bioactivities and the diversity of triazole-containing drugs have attracted wide interest in these heterocycles. Various antibiotic triazole hybrids have been developed, and most of which have shown potent antimicrobial activities. In this review, we summarized the recent advances in triazole hybrids as potential antibacterial agents and their structure-activity relationships (SARs). The information gained through SAR studies will provide further insights into the development of new triazole antimicrobials.

Synthesis and Biological Evaluation of Benzothiazolyl-pyridine Hybrids as New Antiviral Agents against H5N1 Bird Flu and SARS-COV-2 Viruses

A novel series of benzothiazolyl-pyridine hybrids 8a-h and 14a-e were produced from the reaction of enamine derivative 4 with each of the arylcyanoacetamides 5a-h and cyanoacetohydrazides 9a-e. The new products were characterized by spectral techniques (IR, 1H NMR, 13C NMR, and MS). Biological evaluation of 8a-h and 14a-e in vitro against H5N1 and SARS-COV-2 viruses showed that several compounds had significant activity. Compounds 8f-h, which contain fluorine atoms, have better activity against H5N1 and anti-SARS-CoV-2 viruses than the other compounds included in this study. Compound 8h has a trifluoromethyl group at position-3 of the phenyl ring and exhibits a high activity against H5N1 virus with 93 and 60% inhibition at concentrations of 0.5 and 0.25 μmol/μL, respectively, among the tested compounds, and it also showed anti-SARS-CoV-2 virus with a half-maximum inhibition rate of 3.669 μM, among the remaining compounds. The mechanism of action of 8f-h, which is expected to be repurposed against COVID-19, was investigated. The results showed that the compounds have virucidal effects at different stages of the three mechanisms of action. Furthermore, compounds 8f-h were found to possess CoV-3CL protease inhibitory activities with IC50 values of 544.6, 868.2, and 240.6 μg/mL, respectively, compared to IC50 = 129.8 μg/mL of the standard drug lopinavir. Interestingly, compounds 8f-h also showed high inhibitory activity against the H5N1 virus as well as the SARS-CoV-2 virus. Moreover, compounds 8f-h fit admirably into the active site of the SARS-CoV-2 main protease (PDB ID: 6LU7) using the molecular docking Moe software 2015.10.

Meldrum-Based-1H-1,2,3-Triazoles as Antidiabetic Agents: Synthesis, In Vitro α-Glucosidase Inhibition Activity, Molecular Docking Studies, and In Silico Approach

A series of novel alkyl derivatives (2-5a,b) and 1H-1,2,3-triazole analogues (7a-k) of Meldrum's acid were synthesized in a highly effective way by using "click" chemistry and screened for in vitro α-glucosidase inhibitory activity to examine their antidiabetic potential. ¹H NMR, ¹³C-NMR, and high-resolution electrospray ionization mass spectra (HR-ESI-MS) were used to analyze each of the newly synthesized compounds. Interestingly, these compounds demonstrated high to moderate α-glucosidase inhibitory potency having an IC₅₀ range of 4.63-80.21 μM. Among these derivatives, compound 7i showed extraordinary inhibitory activity and was discovered to be several times more potent than the parent compound Meldrum (1) and the standard drug acarbose. Later, molecular docking was performed to understand the binding mode and the binding strength of all the compounds with the target enzyme, which revealed that all compounds are well fitted in the active site of α-glucosidase. To further ascertain the structure of compounds, suitable X-ray single crystals of compounds 5a, 7a, and 7h were developed and studied. The current investigation has shown that combining 1H-1,2,3-triazole with the Meldrum moiety is beneficial. Furthermore, this is the first time that the aforementioned activity of these compounds has been reported.

Discovery of New Boswellic Acid Hybrid 1H-1,2,3-Triazoles for Diabetic Management: In Vitro and In Silico Studies

A series of 24 new 1H-1,2,3-triazole hybrids of 3-O-acetyl-11-keto-β-boswellic acid (β-AKBA (1)) and 11-keto-β-boswellic acid (β-KBA (2)) was designed and synthesized by employing "click" chemistry in a highly efficient manner. The 1,3-dipolar cycloaddition reaction between β-AKBA-propargyl ester intermediate 3 or β-KBA-propargyl ester intermediate 4 with substituted aromatic azides 5a-5k in the presence of copper iodide (CuI) and Hünig's base furnished the desired products-1H-1,2,3-triazole hybrids of β-AKBA (6a-6k) and β-KBA (7a-7k)-in high yields. All new synthesized compounds were characterized by ¹H-, ¹³C-NMR spectroscopy, and HR-ESI-MS spectrometry. Furthermore, their α-glucosidase-inhibitory activity was evaluated in vitro. Interestingly, the results obtained from the α-glucosidase-inhibitory assay revealed that all the synthesized derivatives are highly potent inhibitors, with IC₅₀ values ranging from 0.22 to 5.32 µM. Among all the compounds, 6f, 7h, 6j, 6h, 6g, 6c, 6k, 7g, and 7k exhibited exceptional inhibitory potency and were found to be several times more potent than the parent compounds 1 and 2, as well as standard acarbose. Kinetic studies of compounds 6g and 7h exhibited competitive and mixed types of inhibition, with ki values of 0.84 ± 0.007 and 1.18 ± 0.0012 µM, respectively. Molecular docking was carried out to investigate the binding modes of these compounds with α-glucosidase. The molecular docking interactions indicated that that all compounds are well fitted in the active site of α-glucosidase, where His280, Gln279, Asp215, His351, Arg442, and Arg315 mainly stabilize the binding of these compounds. The current study demonstrates the usefulness of incorporating a 1H-1,2,3-triazole moiety into the medicinally fascinating boswellic acids skeleton.

Pyrazolopyridine: An efficient pharmacophore in recent drug design and development

Among the various heterocyclic molecules employed for drug design and discovery, pyrazolopyridine is one of the promising pharmacophores. Pyrazolopyridine is a result of fusion of pyrazole and pyridine rings. The potent pharmacology of pyrazolopyridine may be the synergistic effect of pyrazole and pyridine moieties in a single framework. It has been used in drug design of a wide range of diseases such as anticancer, antimicrobial, anti-inflammatory, and neuroprotection. Cancer has become a common disease among elderly people now a days that might be because of genetic inheritance to some extent, carcinogens, pollution, and some infectious diseases. Whatever may be the reason, cancer is one of the major causes of deaths worldwide. In addition, over-usage and improper usage of antibiotics have led to drug resistance of microbes. Further, inflammation is a cause of various diseases such as arthritis, and other diseases. Thus, proinflammatory kinases are considered as primary target for inhibition of inflammation. In view of this, a work that compiles potent pharmacology of recently reported pyrazolopyridine analogs has been planned. The review is aimed to discuss pharmacology in brief along with structure-activity relationship (SAR). The review would emphasize importance of pyrazolopyridines in future drug design and discovery and may help in design of potent pharmacological agents.

Sonochemical-Assisted Biogenic Synthesis of Theophrasite β-Ni(OH)2 Nanocluster Using Chia Seeds Extract: Characterization and Anticancer Activity

Theophrasite β-Ni(OH)₂ nanocluster were fabricated via the sonochemical-assisted biogenic method using chia seeds extract as a reducing and stabilizing agent. The optical and morphological feature of the synthesized nanocluster was characterized using UV-Vis, FTIR, FE-SEM-EDS, HR-TEM, DLS, XPS, and XRD analysis. According to FE-SEM and HR-TEM images of the synthesized materials, β-Ni(OH)₂ nanocluster illustrates the hexagonal particle shape with an average size of 5.8 nm, while the EDS results confirm the high purity of the synthesized nanocluster. Moreover, the XRD pattern of the synthesized materials shows typical peaks that match the reference pattern of the Theophrasite form of β-Ni(OH)₂ with a hexagonal crystal system. The XPS analysis illustrates that the prepared samples exhibit both Ni²⁺ and Ni³⁺ with the predominance of Ni²⁺ species. Additionally the in-vitro cytotoxic activity of β-Ni(OH)₂ nanocluster is tested against the MCF7 cell lines (breast cancer cells). The MTT assay results proved that the synthesized β-Ni(OH)₂ nanocluster has potent cytotoxic activity against breast cancer cell lines (IC₅₀: 62.7 μg/mL).

SAR analysis of heterocyclic compounds with monocyclic and bicyclic structures as antifungal agents

Infections caused by eukaryotic organisms, such as fungi, are generally more difficult to treat than bacterial infections. With the widespread use of antifungal drugs in humans and plants, resistance and toxicity have emerged. Therefore, it is desirable to develop new antifungal drugs with low toxicity that are not susceptible to the development of resistance. This review presents a summary of the past 2017 to 2021 years of research on heterocyclic compounds as antifungal agents for use in humans and plants, focusing on the structure-activity relationships (SAR) of these compounds. This review may provide ideas and data for designing and developing new antifungal drugs with fewer side effects compared with currently available drugs.

Novel 1,2,3-Triazole-Coumarin Hybrid Glycosides and Their Tetrazolyl Analogues: Design, Anticancer Evaluation and Molecular Docking Targeting EGFR, VEGFR-2 and CDK-2

This study represents the design and synthesis of a new set of triazole-coumarin-glycosyl hybrids and their tetrazole hybrid analogues possessing various sugar moieties and modified analogues. All the newly synthesized derivatives were screened for their cytotoxic activities against a panel of human cancer cell lines. The coumarin derivatives 10, 13 and 15 derivatives revealed potent cytotoxic activities against Paca-2, Mel-501, PC-3 and A-375 cancer cell lines. These promising analogues were further examined for their inhibitory assessment against EGFR, VEGFR-2 and CDK-2/cyclin A2 kinases. The coumarin-tetrazole 10 displayed broad superior inhibitory activity against all screened enzymes compared with the reference drugs, erlotinib, sorafenib and roscovitine, respectively. The impact of coumarin-tetrazole 10 upon cell cycle and apoptosis induction was determined to detect its mechanism of action. Additionally, it upregulated the levels of casp-3, casp-7 and cytochrome-c proteins and downregulated the PD-1 level. Finally, molecular docking study was simulated to afford better rationalization and gain insight into the binding affinity between the promising derivatives and their targeted enzymes, which could be used as an optimum lead for further modification in the anticancer field.

Click chemistry based synthesis, cytotoxic activity and molecular docking of novel triazole-thienopyrimidine hybrid glycosides targeting EGFR

In the current study, new thienopyrimidine conjugates bearing 1,2,3-triazole core and different sugar moieties have been designed and synthesized by Cu(I)-catalysed click dipolar cycloaddition. The cytotoxic activity of the synthesised conjugates 2, 5, 7, and 13-18 was studied against HCT-116 and MCF-7 cell lines by the MTT assay. The triazole glycosides 16 and 18 provided significant cytotoxic activities against HCT-116 cell lines comparable to that of doxorubicin and other studied compounds. The cytotoxic behaviour against MCF-7 exhibited that all the investigated compounds were more potent than doxorubicin. Moreover, all screened targets were evaluated against mutant EGFR kinase type L858R and the results revealed that the acetylated 1,2,3-triazole glycosides 13-18 exhibited excellent EGFR inhibitory activity in comparison with gefitinib. Furthermore, molecular modelling studies were performed to investigate the binding affinity of the most active compounds to EGFR enzyme.

The Expanding Role of Pyridine and Dihydropyridine Scaffolds in Drug Design

Pyridine-based ring systems are one of the most extensively used heterocycles in the field of drug design, primarily due to their profound effect on pharmacological activity, which has led to the discovery of numerous broad-spectrum therapeutic agents. In the US FDA database, there are 95 approved pharmaceuticals that stem from pyridine or dihydropyridine, including isoniazid and ethionamide (tuberculosis), delavirdine (HIV/AIDS), abiraterone acetate (prostate cancer), tacrine (Alzheimer's), ciclopirox (ringworm and athlete's foot), crizotinib (cancer), nifedipine (Raynaud's syndrome and premature birth), piroxicam (NSAID for arthritis), nilvadipine (hypertension), roflumilast (COPD), pyridostigmine (myasthenia gravis), and many more. Their remarkable therapeutic applications have encouraged researchers to prepare a larger number of biologically active compounds decorated with pyridine or dihydropyridine, expandeing the scope of finding a cure for other ailments. It is thus anticipated that myriad new pharmaceuticals containing the two heterocycles will be available in the forthcoming decade. This review examines the prospects of highly potent bioactive molecules to emphasize the advantages of using pyridine and dihydropyridine in drug design. We cover the most recent developments from 2010 to date, highlighting the ever-expanding role of both scaffolds in the field of medicinal chemistry and drug development.

Radiosynthesis of 5-[18F]Fluoro-1,2,3-triazoles through Aqueous Iodine-[18F]Fluorine Exchange Reaction

In this report, a simple and efficient process to achieve fluorine-18-labeled 1,2,3-triazole is reported. The heteroaromatic radiofluorination was successfully achieved through an iodine–fluorine-18 exchange in an aqueous medium requiring only trace amounts of base and no azeotropic drying of fluorine-18. This methodology was optimized on a model reaction and further validated on multiple 1,2,3-triazole substrates with 18–60% radiochemical conversions. Using this strategy—the radiosynthesis of a triazole-based thiamin analogue—a potential positron emission tomography (PET) probe for imaging thiamin-dependent enzymes was synthesized with 10–16% isolated radiochemical yield (RCY) in 40 min (uncorrected, n > 5).

Design, Hemiysnthesis, crystal structure and anticancer activity of 1, 2, 3-triazoles derivatives of totarol

A new series of diverse triazoles linked to the hydroxyl group of totarol were synthesized using click chemistry approach. The structures of these compounds were elucidated by HRMS, IR and NMR spectroscopy. The structure of compound 3 g was also confirmed by x-ray single crystal diffraction. The cytotoxicity of these compounds was evaluated by the MTT method against four cancer cell lines, including fibrosarcoma HT-1080, lung carcinoma A-549 and breast adenocarcinoma (MDA-MB-231 and MCF-7), and the results indicated that all compounds showed weak to moderate activities against all cancer cell lines with IC₅₀ values ranging from 14.44 to 46.25 μM. On the basis of our research the structure-activity relationships (SAR) of these compounds were discussed. This work provides some important hints for further structural modification of totarol towards developing novel and highly effective anticancer drugs respectively. It is interesting to note that compound 3 g indicated a very significant cytotoxicity against HT-1080 and A-549 cell lines. The molecular docking showed that compound 3 g activated the caspase-3 and inhibited tubulin by forming stable protein-ligand complexes.

Discovery of New Pyrazolopyridine, Furopyridine, and Pyridine Derivatives as CDK2 Inhibitors: Design, Synthesis, Docking Studies, and Anti-Proliferative Activity

New pyridine, pyrazoloyridine, and furopyridine derivatives substituted with naphthyl and thienyl moieties were designed and synthesized starting from 6-(naphthalen-2-yl)-2-oxo-4-(thiophen-2-yl)-1,2-dihydropyridine-3-carbonitrile (1). The chloro, methoxy, cholroacetoxy, imidazolyl, azide, and arylamino derivatives were prepared to obtain the pyridine-⁻C² functionalized derivatives. The derived pyrazolpyridine-N-glycosides were synthesized via heterocyclization of the C²-thioxopyridine derivative followed by glycosylation using glucose and galactose. The furopyridine derivative 14 and the tricyclic pyrido[3′,2′:4,5]furo[3,2-d]pyrimidine 15 were prepared via heterocyclization of the ester derivative followed by a reaction with formamide. The newly synthesized compounds were evaluated for their ability to in vitro inhibit the CDK2 enzyme. In addition, the cytotoxicity of the compounds was tested against four different human cancer cell lines (HCT-116, MCF-7, HepG2, and A549). The CDK2/cyclin A2 enzyme inhibitory results revealed that pyridone 1, 2-chloro-6-(naphthalen-2-yl)-4-(thiophen-2-yl)nicotinonitrile (4), 6-(naphthalen-2-yl)-4-(thiophen-2-yl)-1H-pyrazolo[3,4-b]pyridin-3-amine (8), S-(3-cyano-6-(naphthaen-2-yl)-4-(thiophen-2-yl)pyridin-2-yl) 2-chloroethanethioate (11), and ethyl 3-amino-6-(naphthalen-2-yl)-4-(thiophen-2-yl)furo[2,3-b]pyridine-2-carboxylate (14) are among the most active inhibitors with IC₅₀ values of 0.57, 0.24, 0.65, 0.50, and 0.93 µM, respectively, compared to roscovitine (IC₅₀ 0.394 μM). Most compounds showed significant inhibition on different human cancer cell lines (HCT-116, MCF-7, HepG2, and A549) with IC₅₀ ranges of 31.3–49.0, 19.3–55.5, 22.7–44.8, and 36.8–70.7 μM, respectively compared to doxorubicin (IC₅₀ 40.0, 64.8, 24.7 and 58.1 µM, respectively). Furthermore, a molecular docking study suggests that most of the target compounds have a similar binding mode as a reference compound in the active site of the CDK2 enzyme. The structural requirements controlling the CDK2 inhibitory activity were determined through the generation of a statistically significant 2D-QSAR model.

Bioactive 1,2,3-Triazoles: An Account on their Synthesis, Structural Diversity and Biological Applications

The triazole heterocycle is a privileged scaffold in medicinal chemistry, since its structure is present in a large number of biologically active molecules, including several drugs currently in the market. Due to their vast applications, a wide variety of methods are described for their preparation, such as the 1,3-dipolar cycloaddition and processes involving diazo compounds and diazo transfer reactions. Considering the significant number of contributions from our research group to this chemistry in recent decades, in this account we discuss both the development of new methods for the synthesis of 1,2,3-triazoles and the preparation of new triazole-functionalized biologically active molecules using classical approaches.

Design, Synthesis, Molecular Modeling, Anticancer Studies, and Density Functional Theory Calculations of 4-(1,2,4-Triazol-3-ylsulfanylmethyl)-1,2,3-triazole Derivatives

New conjugates of substituted 1,2,3-triazoles linked to 1,2,4-triazoles were synthesized starting from the appropriate S-propargylated 1,2,4-triazoles 7 and 8. Ligation of 1,2,4-triazoles to the 1,2,3-triazole core was performed through Cu(I)-catalyzed cycloaddition of 1,2,4-triazole-based alkyne side chain 7 and/or 8 with several un/functionalized alkyl- and/or aryl-substituted azides 9-15 to afford the desired 1,4-disubstituted 1,2,3-triazoles 16-27, using both classical and microwave methods. After their spectroscopic characterization (infrared, 1H, 13C nuclear magnetic resonance, and elemental analyses), an anticancer screening was carried out against some cancer cell lines including human colon carcinoma (Caco-2 and HCT116), human cervical carcinoma (HeLa), and human breast adenocarcinoma (MCF-7). The outcomes of this exploration revealed that compounds 17, 22, and 25 had a significant anticancer activity against MCF-7 and Caco-2 cancer cell lines with IC50 values of 0.31 and 4.98 μM, respectively, in relation to the standard reference drug, doxorubicin. Enzyme-docking examination was executed onto cyclin-dependent kinase 2; a promising aim for cancer medication. Synthesized compounds acquiring highest potency showcased superior interactions with the active site residue of the target protein and exhibited minimum binding energy. Finally, the density functional theory (DFT) calculations were carried out to confirm the outcomes of the molecular docking and the experimental findings. The chemical reactivity descriptors such as softness (δ), global hardness (η), electronegativity (χ), and electrophilicity were calculated from the levels of the predicted frontier molecular orbitals and their energy gap. The DFT results and the molecular docking calculation results explained the activity of the most expectedly active compounds 17, 22, and 25.

Design, synthesis and anticancer activity of novel pyrimidine and pyrimidine-thiadiazole hybrid glycosides

New 1,3,4-thiadiazole thioglycosides linked to substituted pyrimidines were synthesized via glycosylation of 1,3,4-thiadiazole thiol compounds. Also, novel 1,2,3-triazole derivatives linked to carbohydrate units were prepared using the standard click chemistry conditions employing the Cu(I)-catalyzed azide-alkyne cycloaddition of substituted-aryl-azides with a selection of alkyne-functionalized sugars. The chemical structures of the new derivatives were verified using various spectroscopic techniques, such as IR, ¹H NMR, ¹³C NMR and elemental analyses. The cytotoxic activities of the prepared compounds were investigated in vitro against human liver cancer (HepG-2) and human breast adenocarcinoma (MCF7) cell lines. In addition, the biological evaluation of the new compounds involved the investigation of their effects on a human normal retinal pigmented epithelial cell line (RPE1) using the MTT assay.

Design, Synthesis, and Antimicrobial Activities of 1,2,3-Triazole Glycoside Clickamers

Bacterial resistance remains a significant threat and a leading cause of death worldwide, despite massive attempts to control infections. In an effort to develop biologically active antibacterial and antifungal agents, six novel aryl-substituted-1,2,3-triazoles linked to carbohydrate units were synthesized through the Cu(I)-catalyzed azide-alkyne cycloaddition CuAAC of substituted-arylazides with a selection of alkyne-functionalized sugars. The chemical structures of the new derivatives were verified using different spectroscopic techniques. The novel clicked 1,2,3-triazoles were evaluated for in vitro antibacterial activity against Gram-positive Staphylococcus aureus and Gram-negative Pseudomonas aeruginosa, and the obtained results were compared with the activity of the reference antibiotic "Ampicillin". Likewise, in vitro antifungal activity of the new 1,2,3-triazoles was investigated against Candida albicans and Aspergillus niger using "Nystatin" as a reference drug. The results of the biological evaluation pointed out that Staphylococcus aureus was more susceptible to all of the tested compounds than other examined microbes. In addition, some tested compounds exhibited promising antifungal activity.

Synthesis and Cytotoxic Activity of New Thiazolopyrimidine Sugar Hydrazones and Their Derived Acyclic Nucleoside Analogues

New thienyl- or chlorophenyl-substituted thiazolopyrimidine derivatives and their derived sugar hydrazones incorporating acyclic d-galactosyl or d-xylosyl sugar moieties in addition to their per-O-acetylated derivatives were synthesized. Heterocyclization of the formed sugar hydrazones afforded the derived acyclic nucleoside analogues possessing the 1,3,4-oxadiazoline as modified nucleobase via acetylation followed by the cyclization process. The cytotoxic activity of the synthesized compounds was studied against human breast cancer MCF7 and MDA-MB-231 cell lines as well as human colorectal cancer HCT 116 and Caco-2 cell lines. High activities were revealed by compounds 1, 8, 10, 11, and 13 against Caco-2 and MCF7 cells in addition to moderate activities exhibited by other compounds against HCT116 or MDA-MB-231 cells.

Synthesis and Cytotoxic Activity of New 1,3,4-Thiadiazole Thioglycosides and 1,2,3-Triazolyl-1,3,4-Thiadiazole N-glycosides

New 1,3,4-thiadiazole thioglycosides linked to substituted arylidine systems were synthesized via glycosylation of the prepared 1,3,4-thiadiazole thiol compounds. Click strategy was also used for the synthesis of new 1,3,4-thiadiazole and 1,2,3-triazole hybrid glycosides by reaction of the acetylenic derivatives with different glycosyl azids followed by deacetylation process. The cytotoxic activities of the prepared compounds were studied against HCT-116 (human colorectal carcinoma) and MCF-7 (human breast adenocarcinoma) cell lines using the MTT assay. The results showed that the key thiadiazolethione compounds 2 and 3, the triazole glycosides linked to p-methoxyarylidine derivatives 14 and 15 in addition to the free hydroxyl glycoside 20 were found potent in activity comparable to the reference drug doxorubicin against MCF-7 human cancer cells. The acetylenic derivative 2 and glycoside 20 were also found highly active against HCT-116 cell lines.

Synthesis and anti-H5N1 virus activity of triazole- and oxadiazole-pyrimidine hybrids and their nucleoside analogs

New 1,2,3-triazole glycosides and 1,2,4-thioglycosides incorporating a substituted pyrimidinedione ring system were synthesized via click dipolar cycloaddition and heterocyclization of hydrazine-1-carbodithioate derivatives, respectively. The sugar hydrazine derivatives linked aminodimethyluracil were also prepared. In addition, the oxadiazoline substituted with acyclic sugar moieties linked to the pyrimidinedione as acyclic nucleoside analogs were synthesized. The antiviral activity of the synthesized compounds against avian influenza H5N1 virus was investigated and compounds 18, 13 and 19 showed good activities against the virus strains.

Synthesis, Docking Studies into CDK-2 and Anticancer Activity of New Derivatives Based Pyrimidine Scaffold and Their Derived Glycosides

BACKGROUND & OBJECTIVE

New diaryl-substituted pyrimidinedione compounds, their thioxo derivatives as well as their bicyclic thiazole compounds were synthesized and characterized.

METHODS

The glycosylamino derivatives of the synthesized disubstituted derivatives of the pyrimidine scaffold were also prepared via reaction of the N3-amino derivatives with a number of monosaccharides followed by acetylation.

RESULTS

The anticancer activity of the synthesized compounds was studied against human liver cancer (HepG2) and RPE-1cell lines. Compounds 2a, 2b, 3a and 12 showed potent activities with IC50 results comparable to that of doxorubicin.

CONCLUSION

Docking investigations into Cyclin-dependent kinase 2 (CDK-2) enzyme, a potential target for cancer medication, were also reported showing the possible binding interaction into the enzyme active site to support their activity behavior.

Synthesis and Anticancer Activity of New ((Furan-2-yl)-1,3,4-thiadiazolyl)-1,3,4-oxadiazole Acyclic Sugar Derivatives

New sugar hydrazones incorporating furan and/or 1,3,4-thiadiazole ring systems were synthesized by reaction of the corresponding hydrazide with different aldose sugars. Heterocyclization of the formed hydrazones afforded the derived acyclic nucleoside analogues possessing the 1,3,4-oxadiazoline as modified nucleobase via acetylation followed by the heterocyclization process. The anticancer activity of the synthesized compounds was studied against human liver carcinoma cell (HepG-2) and at human normal retina pigmented epithelium cells (RPE-1). High activities were revealed by compounds 3, 12 and 14 with IC₅₀ values near to that of the reference drug doxorubicin.

Design, Synthesis of New Pyridine and Pyrimidine Sugar Compounds as Antagonists Targeting the ERα via Structure-Based Virtual Screening

BACKGROUND

New aryl substituted cyclohepta[b]pyridine and cyclohepta[d]pyrimidine derivatives were synthesized. The sugar hydrazones of the synthesized pyridine and pyrimidine compounds were also prepared.

METHOD

In addition, the 1,3,4-oxadiazolyl acyclic C-nucleoside analogs of the pyridine system were prepared. The hemolytic, prebiotic, anticancer and antimicrobial activities of some of the synthesized compounds were also studied. Compounds 10 and 12 showed high activity against MCF-7, HEPG-2 and HCT-116 cell lines with IC50 at range 3.56-8.55 µg/mL. In addition, the synthesized condensed thiopyrimidine derivative 10 exhibited more potent bactericidal activity while compound 7 demonstrated potent antifungal activity against Aspergillus niger. Furthermore, the synthetic compounds of the pyrimidine base promoted the growth of lactic acid bacteria.

RESULTS

The predicted binding patterns of three of the prepared derivatives as possible antagonists against ERα were investigated which showed good binding patterns.