Search

The exponential development of resistance to conventional chemical insecticides adds another important motive for the creation of novel insecticidal active agents. One of the keys to meeting this challenge is the exploration of novel classes of insecticidal molecules with different modes of action. Herein, a novel series of spiro pyrimidine derivatives was prepared using some green synthetic methodologies such as microwave irradiation, and sonication under ultrasound waves. Spiro pyrimidine aminonitrile 1 is a key starting material for the synthesis of targets 2–9 by reaction with different carbon electrophiles and nitrogen nucleophiles. The structures of all the newly synthesized compounds were approved using spectral data. The toxicological efficiency and biological impacts of the synthesized spiro pyrimidine derivatives were assessed against Culex pipiens L. larvae. The toxicity of synthesized compounds showed remarkable variations against the C. pipiens larvae. Where, 3, 4 and 2 were the most efficient compounds with LC50 values of 12.43, 16.29 and 21.73 µg/mL, respectively. While 1 was the least potent compound with an LC50 value of 95.18 µg/mL. As well, other compounds were arranged according to LC50 values as follows 5 > 7 > 6 > 9 > 8. In addition, 3 and 4 exhibited significant prolongation of the developmental duration and greatly inhibited adult emergence. Moreover, many morphological deformities were observed in all developmental stages. Furthermore, cytotoxicity of the most effective compounds was assessed against the normal human cells (WI-38) as non-target organisms, where compounds 2, 4 and 3 showed weak to non-toxic effects. The study of binding affinity and correlation between chemical structure and reactivity was carried out using molecular docking study and DFT calculations to investigate their mode of action. This study shed light on promising compounds with larvicidal activity and biological impacts on the C. pipiens life cycle. [ABSTRACT FROM AUTHOR]

Mer and c-Met kinases, which are commonly overexpressed in various tumors, are ideal targets for the development of antitumor drugs. This study focuses on the design, synthesis, and evaluation of several 2-substituted aniline pyrimidine derivatives as highly potent dual inhibitors of Mer and c-Met kinases for effective tumor treatment. Compound 18c emerged as a standout candidate, demonstrating robust inhibitory activity against Mer and c-Met kinases, with IC50 values of 18.5 ± 2.3 nM and 33.6 ± 4.3 nM, respectively. Additionally, compound 18c displayed good antiproliferative activities on HepG2, MDA-MB-231, and HCT116 cancer cells, along with favorable safety profiles in hERG testing. Notably, it exhibited exceptional liver microsomal stability in vitro, with a half-life of 53.1 min in human liver microsome. Compound 18c also exhibited dose-dependent cytotoxicity and hindered migration of HCT116 cancer cells, as demonstrated in apoptosis and migration assays. These findings collectively suggest that compound 18c holds promise as a dual Mer/c-Met agent for cancer treatment. [ABSTRACT FROM AUTHOR]

The photocatalytic activity of graphitic carbon nitride (g-C 3 N 4) depends to a large extent on its morphology and electronic band structure. In order to design a photocatalyst with suitable structural property and high efficiency of photo-generated carrier separation, herein, the pyrimidine doped g-C 3 N 4 is prepared by a conventional one-pot copolymerization of urea and 2,4,6-Triaminopyrimidine (TAP). Such TAP organic molecule can not only regulate the electronic structure of conjugated system and distort heptazine units, but also affect the polymerization of precursor urea. As expected, the optimized photocatalyst shows a high photocatalytic hydrogen evolution activity of 453 μmol·h−1 under visible light irradiation, which is 4.41 times over that of pure g-C 3 N 4. Such enhanced photocatalytic performance is attributed to the introduction of pyrimidine ring which facilitates the electrons delocalization in the in-plane structure, enlarges the specific surface area, and broadens the visible light absorption range. • The electron delocalization is promoted on pyrimidine doped graphitic carbon nitride. • Homogeneous carbon doping is achieved on a heptazine ring. • The specific surface area of the modified sample is up to 150.07 m2 g−1. [ABSTRACT FROM AUTHOR]

The current research is directed to construct a novel category of linear annulated chromeno[3',2':5,6]pyrido[2,3-d][1,3]thiazolo[3,2-a]pyrimidines. The chemical reactivity of the recently synthesized aldehyde 1 was examined toward a diversity cyclic methylene ketones, cyclic enamines and cyclic enols. Friedländer condensation of aldehyde 1 with 1,3-cyclohexanediones gave the multi-linear chromenopyrido- pyrimidothiazoloquinolines 2 and 3. Also, treating aldehyde 1 with some pyrazolones furnished annulated chromenopyridopyrazolopyridothiazolopyrimidines 4-6. Further, 1,3-thiazolidine-2,4-dione and barbituric acid condensed with aldehyde 1 giving chromenopyridothiazolopyridothiazolopyrimidine 7 and chromenopyridopyrimido-thiazolopyridopyrimidine 8, respectively. Moreover, reacting aldehyde 1 with cyclic enamines (6-amino-2-thiouracil and 6-amino-1,3-dimethyluracil) and cyclic enols (4-hydroxycoumarin and 1-ethyl-4-hydroxyquinolin-2(1H)-one) furnished polyfused heterocycles 9-12, respectively. During in vitro investigation of the antimicrobial efficiency, the synthesized compounds showed considerable activity against yeast and fungal strains, as well as moderate to high activity against Gram-positive and Gram-negative bacteria. Polyfused compounds 4-6 showed significant efficiency against all types of tested microorganisms. [ABSTRACT FROM AUTHOR]

A mild Oxone® mediated reaction for direct regioselective C−H selenylation and thiocyanation of pyrazolo[1,5‐a]pyrimidines is established at ambient temperature. This practical and efficient methodology employs Oxone® as a user friendly, green, non‐toxic and cheap reagent to facilitate selenylation and thiocyanation at room temperature. The present method offers high regioselectivity, broad substrate scope, mild conditions and excellent yields. Further, this eco‐friendly approach could easily be extended for mild C−H selenylation and thiocyanation of other heterocycles. Mechanistic studies indicate that the reaction occurs through electrophilic substitution mechanism via generation of an electrophilic chalcogen species. [ABSTRACT FROM AUTHOR]

In this investigation, a novel group of compounds, 2-mercapto-benzofuro-pyrimidine derivatives, were synthesized from 2-hydroxy-5-nitro-1-benzonitrile (1) as the starting material. This was treated with various haloketones to provide the corresponding 1-(3-amino-5-nitro-1-benzofuran-2-yl) ethan-1-one (2a-d), which was then treated with ammonium thiocyanate and acetyl chloride to yield N-[(2-acetyl-5-nitro-1-benzofuran-yl) carbamothioyl]acetamide (3a-d). Further, it was reflux with sodium hydroxide yields 4-methyl/aryl-8-nitro[1] benzofuro[3,2-d]pyrimidine-2-thiol(4a-d). To obtain the appropriate acids, continue stirring compounds (4ad) with chloroacetic acid to obtain [(4-methyl-8-nitro[1]benzofuro[3,2-d]pyrimidin-2-yl)sulfanyl]acetic acid (5a-d). The structures of all the newly synthesized compounds have been established by spectral studies such as Fourier-transform infrared, Proton nuclear magnetic resonance and Mass spectra. Furthermore, all the new compounds were screened antibacterial and antifungal activity against human pathogenic viz. gram +Ve and gram -Ve organisms by agar well diffusion method. In addition, molecular docking was performed for all synthesized compounds using high inhibition organisms selected protein of both genetic and non-genetic algorithm techniques, where result are demonstrate in an excellent docking energy. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the anti-inflammatory, anti-cancer, anti-parkinsonian, anti-microbial, analgesic, and anti-hyperglycemic properties of a variety of poly-fused pyrimidine derivatives. Methods: A novel series of fused pyrimidine derivatives 1-6 were synthesized by reacting amino pyrazole derivatives with active methylene derivatives to give the corresponding compounds 1-6. Anti-parkinsonian activity was investigated with benzotropene as a reference drug, anti-inflammatory effect in mice was evaluated using carrageenan in paw edema with indomethacin as reference drug, antimicrobial activity was assessed using nutritional agar with ciprofloxacin and ketoconazole as reference drugs, analgesic activity was evaluated using valdecoxib as reference drug, anti-hyperglycemic activity was investigated using alloxan and sucrose models (SLM) with pioglitazone as reference drug and anticancer activity was investigated using the MTT micro-cultured tetrazolium assay method with doxorubicin as reference drug. Results: Pyrimidine derivatives 1-6 possess significant active anti-parkinsonian, anti-inflammatory, antimicrobial, analgesic, anti-hyperglycemic and anticancer activities in comparison to the reference drugs used for each model. Compared to Benzotropene®, compounds 1 and 3 showed a significantly stronger anti-parkinsonian activity (p < 0.03). Compound 3 showed a significantly stronger anti-inflammatory effect than Indomethacin® (p < 0.05). Compounds 5 and 6 exhibited significant anti-microbial activity compared to ciprofloxacin® (p < 0.05). Compounds 4 and 6 exhibited significantly improved analgesic activity as compared to Valdecoxib® (p < 0.01). Compounds 1 and 3 exhibited significantly higher antihyperglycemic effects in SLM model when compared to pioglitazone® (p < 0.02). Compound 5 demonstrated the highest activity against human colon cancer cell line (HT-29) and human prostate cancer cell line (DU145), and also, significantly improved level of efficacy against human lung cancer cell line (A549) compared to Doxorubicin® (p < 0.02). Conclusion: Using the six pyrimidine derivatives 1 - 6 as a lead molecule, a novel class of clinically beneficial anti-cancer, anti-inflammatory, anti-microbial, analgesic, and anti-hyperglycemic drugs may be produced. [ABSTRACT FROM AUTHOR]

New cytisine-thienopyrimidine hybrid molecules were synthesized by reacting cytisine with 4-chlorothieno [2,3-d]pyrimidines in the presence of Et3N. The solvent effect on the course of the reaction was studied. The structures of the obtained compounds were elucidated using IR, 1H and 13C NMR spectroscopy and TLC-MS spectrometry. X-ray crystal structure analyses of the synthesized compounds were performed. [ABSTRACT FROM AUTHOR]

Pyrimidines have become an increasingly important core structure in many drug molecules over the past 60 years. This article surveys recent areas in which pyrimidines have had a major impact in drug discovery therapeutics, including anti-infectives, anticancer, immunology, immuno-oncology, neurological disorders, chronic pain, and diabetes mellitus. The article presents the synthesis of the medicinal agents and highlights the role of the biological target with respect to the disease model. Additionally, the biological potency, ADME properties and pharmacokinetics/pharmacodynamics (if available) are discussed. This survey attempts to demonstrate the versatility of pyrimidine-based drugs, not only for their potency and affinity but also for the improved medicinal chemistry properties of pyrimidine as a bioisostere for phenyl and other aromatic π systems. It is hoped that this article will provide insight to researchers considering the pyrimidine scaffold as a chemotype in future drug candidates in order to counteract medical conditions previously deemed untreatable. [ABSTRACT FROM AUTHOR]

This article provides a review of recent advances in the synthesis and biological activities of functionalized pyrimidines. It discusses the synthesis and pharmacological activities of pyrimidines in the areas of anticancer, antidiabetes, and antioxidant properties. The article also highlights the potential applications of novel pyrimidine compounds in various fields, including their antioxidant, anti-inflammatory, antibacterial, and antiviral activities. The authors acknowledge the support of Mohanlal Sukhadia University in India. [Extracted from the article]

This document presents a method for synthesizing pyrano[2,3-d]pyrimidines using tris(hydroxymethyl)aminomethane (THAM) as a catalyst. The reactions were carried out in a water/ethanol solution at room temperature and resulted in high yields of the desired compounds. The THAM catalyst could be reused multiple times with only a slight decrease in yield. The article suggests that this simple and environmentally friendly method may encourage further research and synthesis of these heterocyclic systems. The research was supported by the Research Council of the Apadana Institute of Higher Education. [Extracted from the article]

A series of new 8-decylthio-10-methylthio-pyrimido[5,4-e][1,2,4]triazolo[1,5-c]pyrimidine derivatives was prepared and characterized by FTIR, 1H NMR, 13C NMR, and HRMS. The bioassay results revealed that the title compounds had moderate to excellent insecticidal activities against Aphis fabae at a concentration of 500 mg/L. Among them, 8-(decylthio)-2-((4-chlorophenoxy)methyl)-5-propyl-10-(methylthio)-5,6-dihydropyrimido[5,4-e][1,2,4]triazolo[1,5-c]pyrimidine (4l) exhibited the highest insecticidal activity, with 95% mortality. Moreover, 8-(decylthio)-2-((2,4-dichlorophenoxy)methyl)-5-propyl-10-(methylthio)-5,6-dihydropyrimido[5,4-e][1,2,4]triazolo[1,5-c]pyrimidine (4i) showed broad-spectrum postemergence herbicidal activities against Abutilon theophrasti, Amaranthus spinosus, Chenopodium album, Digitaria sanguinalis, Echinochloa crusgalli, and Setaria viridis, which were equivalent to the positive control flumetsulam. However, all new synthesized compounds displayed weak fungicidal activity against four kinds of phytopathogenic fungi including Botrytis cinerea, phytophythora capsici, Elsinoe fewcetti, and Diaporthe medusaea. Compound 4l with remarkable insecticidal activity, and compound 4i with excellent herbicidal activity could be promising lead compounds for further investigation. [ABSTRACT FROM AUTHOR]

The essential aim of the present study is designed to utilize 4,9-dimethoxy-5-oxo-5H-furo[3,2-g]chromene-6-carbonitrile (1) to build some novel heterocyclic systems containing benzofurans as well as furo[3,2-g]chromenes. Ring opening ring closure reactions of compound 1 with N-phenyl-2-cyanoacetamide produced 8-amino-furochromenopyridine-7-carboxamide 2, which cyclized with some electrophilic reagents giving furochromenopyridopyrimidines (63–73% yields). The reaction of carbonitrile 1 with pyrazolone derivatives yielded furochromenopyrazolopyridines 10 and 11 in good yields. Also, benzo[h]furochromeno naphthyridine 13 was synthesized from recyclization of carbonitrile 1 with 1-ethyl-4-hydroxyquinolin-2(1H)-one (12). On a different mechanism, recyclization of carbonitrile 1 with some 1,3-binucleophiles afforded pyrido[2,3-d]pyrimidines (14 and 15), pyrimido[1,2-a]pyrimidine 17 and pyrimido[2,1-c][1,2,4]triazine 19 in suitable yields (62–71%). Finally, the reaction of carbonitrile 1 with 1,3-cyclohexanedione and 1,4-cyclohexanedione in 2:1 molar ratio yielded polyfused systems 20 and 21, respectively. Based on spectral and analytical results, the structures of the all products were inferred. [ABSTRACT FROM AUTHOR]

The pyrimidine scaffold represents one of the privileged structures in chemistry, and there has been an increase in number of studies utilizing this scaffold and its derivatives. A series of 2-amino pyrimidines were synthesized by the reaction of ketene dimethyl thio-acetals with guanidinium nitrate in presence of sodium ethoxide in ethanol under reflux condition. Spectral analysis of the final compounds has been carried out using IR, 1H NMR, 13C NMR spectroscopy and HRMS. Further, the structure of one of the derivatives 4-ethoxy-6-(naphthalen-1-yl) pyrimidin-2-amine (2d) was confirmed by single crystal X-ray diffraction technique. X-ray diffraction analysis for 2d has been reported. The crystal structure of 2d is stabilized by intermolecular N–H...N, C–H...π and π...π weak interactions. To check whether pyrimidine could be ligands for two kinases involved in cancer, docking studies were performed. Few of the compounds showed strong binding affinity with IGF1R and EGFR. [ABSTRACT FROM AUTHOR]

This article discusses the synthesis of a potential anti-HIV agent called 2'-deoxy-2'-β-fluoro-4'-azido-5-fluorouridine (1). The authors describe the design and synthesis of this nucleoside analogue, which is structurally modified to mimic physiological nucleosides. The compound was successfully synthesized in nine steps starting from 1,3,5-O-tribenzoyl-2-deoxy-2-fluoro-d-arabinofuranoside. In vitro biological evaluation showed that the compound exhibited good antiviral activity against HIV-1 infection. This research contributes to the development of novel nucleoside analogues for the treatment of viral infections. [Extracted from the article]

This study reports synthesizing and characterizing imidazolium‐based ionic liquids (ILs) using substituted benzoates as anions. Thermal stability of ILs described using thermogravimetric analysis (TGA). One inherent property of ILs is aggregates or cluster formation due to supramolecular interactions. The supramolecular interaction in synthesized ILs has been studied through Electrospray ionization mass spectrometry (ESI‐MS). The potential of ILs as organic catalysts is investigated in multicomponent reaction (MCR) using urea, malononitrile, and different aromatic aldehydes to prepare phenyl pyrimidines derivatives. The results demonstrate that catalysis with ILs effectively reduces reaction time and enhances yield. ILs entities are hypothesized to form new assemblies with reactive moieties of reactants through supramolecular interactions. The ILs can be reused and recycled. [ABSTRACT FROM AUTHOR]

The study focused on developing new triazolopyrimidine derivatives as potential DNA Gyrase inhibitors and antimicrobial agents. The compounds were designed, synthesized, and evaluated for their biological activities, safety, and ADMET properties. Encouragingly, the initial results showed promising potency and acceptable ADME parameters, forming a strong basis for further drug development research. The newly synthesized compounds were verified through spectra, mass, and elemental analysis. Notably, several compounds exhibited significant activity against both Gram‐positive and Gram‐negative bacteria, with MIC values ranging from 100 μg/ml to 250 μg/ml. importantly, the compounds were found to be safe, with no reported adverse effects or toxicities. Among the tested compounds, compound 2 m stood out as an excellent DNA Gyrase inhibitor, with an IC50 value of 0.89 μM, comparable to the reference drug ciprofloxacin with an IC50 value of 0.91 μM. Molecular docking studies confirmed that the compounds′ binding mode and docking scores were similar to ciprofloxacin, validating their antibacterial activity via DNA Gyrase inhibition. The research provides valuable insights into the potential of these newly synthesized triazolopyrimidine derivatives as DNA Gyrase inhibitors and antimicrobial agents. Their promising antibacterial activity and safe profile make them potential candidates for further development as antimicrobial agents. [ABSTRACT FROM AUTHOR]

Pyrimidine derivatives have attracted much attention in medicinal chemistry because of their diversified biological properties and potential therapeutic applications. The Suzuki‐Miyaura, Sonogashira, and Buchwald‐Hartwig coupling reactions provide flexible methods for synthesizing structurally diverse pyrimidine derivatives. These reactions can modify the pyrimidine structure to incorporate different functional groups and substitution patterns, improving the pharmacological activities and maximizing the drug‐like properties. Using other coupling partners, such as aryl and heteroaryl moieties, has produced novel pyrimidine‐based scaffolds with enhanced bioactivity profiles. This comprehensive review examines the biological activities of pyrimidine derivatives, concentrating on how their diversification via coupling reactions utilizing synthetic techniques has affected their pharmacological properties. Investigating various biological effects and exploring novel artificial techniques present great opportunities for creating next‐generation medicines with improved efficacy and selectivity. [ABSTRACT FROM AUTHOR]

Two series of substituted thieno[3,2-d]pyrimidine derivatives as EZH2 inhibitors were synthesized via structural modifications of tazemetostat. The antiproliferative activity of compounds against SU-DHL-6, WSU-DLCL-2, K562, H358 and H1703 cancer cell lines and the toxicity against HEK293T cells were evaluated. The most promising compound 12e had a remarkable antitumor activity against SU-DHL-6, WSU-DLCL-2 and K562 cells (IC50 = 0.55 μM, 0.95 μM and 1.68 μM, respectively) and low toxicity against HEK-293T cells (CC50 = 15.09 μM). The preliminary structure–activity relationship (SAR) studies indicate that piperidine-2,6-dione was more suitable for a P1 moiety and benzyl-linked morpholine for a P5 moiety, which were beneficial for improving the antitumor activities. The biological evaluation showed that 12e can significantly affect lymphoma cell morphology, and induce the apoptosis of SU-DHL-6 cells in a concentration-dependent manner and inhibit their migration. These findings indicated that 12e would be an attractive chemical tool for the further optimization and evaluation of new EZH2 inhibitors. [ABSTRACT FROM AUTHOR]

A novel series of oxazolyl‐pyrimidine derivatives (11 a–j) have been synthesized and structures were confirmed by spectral data. The synthesized compounds were assessed for cytotoxic profile towards human cervix cancer (SiHa), lung cancer (A549), breast cancer (MCF‐7), and colon cancer (Colo‐205) cell lines by employing MTT assay and using etoposide as the positive control. The heteroaryl compounds having the terminal pyridyl (11 a) and thiazolyl (11 b) groups showed superior cytotoxic potency against cervix and lung cancer cell lines and varying methoxy substituted derivatives 11 c–11 e have excellent to good cytotoxic properties. Compound 11 a and 11 b have IC50 values in the range of 0.01±0.0034 to 0.17±0.059 μM and 0.10±0.038 to 0.66±0.077 μM respectively in the tested cell lines. The selected compounds 11 a and 11 b were studied by molecular docking to assess the binding interactions, binding energies, and possible mechanisms. The in‐silico ADME properties were calculated and all the compounds have the desired properties of drug‐like molecules. The toxicity results indicate that all the compounds are free from toxicity except 11 j, which has high tumorigenic properties. The optimized structure, energies of frontier molecular orbitals, molecular electrostatic potential, and NLO parameters for compound 11 a were determined using DFT/B3LYP level with a 6‐311++G(d,p) basis set. [ABSTRACT FROM AUTHOR]

Hot‐water‐soluble starch (HWSS) was employed as binder for fabrication of a composite from magnetite and Ag nanoparticles (NPs). Electron microscopy images showed a good dispersion of magnetite NPs in the matrix of HWSS. This observation indicates that HWSS tends to coat the maximum surface of magnetite by encapsulation of individual magnetite NPs, leading to disassembly of their aggregates. The HWSS‐coated magnetite NPs were employed as nano‐support for immobilization of fine Ag NPs generated in situ via reduction of Ag+ cations by glucose. Monitoring of the formation and growth of Ag NPs by UV–Vis spectroscopy made it possible to set up an optimal condition for fabrication of the nano‐composite and to verify the supremacy of HWSS‐coated magnetite NPs over bare magnetite NPs as support in this new protocol. Valuable insights into the texture of the nano‐composite were obtained by VSM, FT‐IR and XRD studies. The bio‐derived nano‐composite displayed an interesting magnetic property and an efficient catalytic activity in the three‐component synthesis of pyrano[2,3‐d]pyrimidines. It is a robust heterogeneous catalyst and can be simply retrieved from reaction mixtures by magnetic separation method. [ABSTRACT FROM AUTHOR]

In the present study a series of ethyl 4-(substituted)-2-methyl-4H-benzo[4,5]thiazolo[3,2-a]pyrimidine-3-carboxylate and ethyl 4-(substituted)-8-methoxy-2-methyl-4H-benzo[4,5]thiazolo[3,2-a]pyrimidine-3-carboxylate have been synthesized and evaluated for their preliminary antibacterial, antifungal, antimycobacterial, antioxidant and antimalarial activity. Among all the synthesized derivatives some of the compounds exists good biological activity which is similar to that of standard drugs. These facts make the compounds interesting candidates for further evaluation of their efficacy in the treatment microbial, tubercular and malarial disease. [ABSTRACT FROM AUTHOR]

An efficient and facile protocol for the synthesis of pyrimidine, pyridine and pyrazole ring systems was reported, Reaction of isothiocyanate with enaminone to give pyrimidinthione 4, the reactions of pyrimidinthione 4 with several active species such as ethyliodide, benzaldehyde, p-anisidine, acetylacetone were studied, the reactions of isothiocyanate 1 with active species such as ethyl cyanoacetate to form thioamide then oxazine, thiourea togivethiosemicarbazide, hydrazine, and phenylhydrazine resulted in pyrimidines. Novel compounds were tested for biological activity against Gram+ bacteria (Bacillus subtilis and Staphylococcus aureus) and Gram– bacteria (E. Coli and Klebsiella pneumonia) using Gentamycin as reference standard drug, Results showed novel compounds as potent antibacterial agents against all bacterial strains except (Klebsiella pneumonia bacteria). [ABSTRACT FROM AUTHOR]

Imidazo[1,2-a]pyrimidine derivatives are a class of biologically active parent nucleus structures containing both imidazole and pyrimidine rings, which are important intermediates for the synthesis of a variety of drugs. This class of structures has attracted a lot of attention of researchers, and more and more synthetic strategies have been developed and reported. Currently, the main synthetic strategies are one-pot multi-component methods, microwave radiation, ultrasonic irradiation and other auxiliary Knoevenagel condensation and Michael addition methods to obtain these compounds, with the aim of achieving high yields, low time consumption and environmental friendliness. This review comprehensively summarizes the various synthetic methods as well as mechanism recently reported for the construction of this remarkable backbone structure and further used for the development of new chemical synthesis strategies and drug development as it has a wide range of applications in medicinal chemistry. In order to provide some impetus to the research of synthetic methods for this structure. [ABSTRACT FROM AUTHOR]

A novel access to pyrrolo[3,4-d]pyrimidine scaffold via tandem Staudinger/intramolecular aza-Wittig reaction of 5-acyl-4-(1-azidoalkyl)-3,4-dihydropyrimidin-2(1H)-ones promoted by PPh3 was developed. Synthesis of the starting pyrimidinones involved the reaction of readily available N-[(2-azido-1-tosyl)alkyl]ureas with Na enolates of benzoylacetone or acetylacetone followed by acid-catalyzed dehydration of the resulting products without their isolation. [ABSTRACT FROM AUTHOR]

The pyrido[2,3‐d]pyrimidine moieties are one of the most biologically widespread heterocyclic compounds as antimicrobial, antioxidant, antitubercular, antiviral and anti‐inflammatory. Hence, we synthesized an efficient new series of 2‐thioxo‐pyrido[2,3‐d]pyrimidinone, 2‐hydrazinyl‐(quinolin‐2‐yl)pyrido[2,3‐d]pyrimidinone,N′‐(quinolin‐2‐yl)‐pyrido[2,3‐d]pyrimidine‐(formo/aceto)‐hydrazide and substituted‐(quinolin‐2‐yl)pyrido[2,3‐d][1,2,4]triazolo[4,3‐a]pyrimidinone derivatives. The characterization of new compounds was corresponded by using spectroscopic techniques, IR, NMR and Mass spectra. In vitro, all compounds were evaluated as antimicrobial activity compared with cefotaxime sodium and nystatin as the standard drug. This work deals with the exploration of the new heterocyclic compounds and medicinal diversity of quinoline‐pyrido[2,3‐d][1,2,4]triazolo[4,3‐a]pyrimidine derivatives that might pave the way for long in the discovery of therapeutic medicine for future drug design. [ABSTRACT FROM AUTHOR]

The δ isoform of class I PI3K (PI3Kδ) has been shown as a promising target for the treatment of hematologic malignancies and immune diseases. Herein, a series of pyrido[3,2‐d]pyrimidine derivatives were designed, synthesized and evaluated for the preliminary bioactivity. Compared with idelalisib, compound S5 exhibited excellent enzyme activity against PI3Kδ (IC50 = 2.82 nM) and strong antiproliferation activity against SU‐DHL‐6 cells (IC50 = 0.035 μM). Besides, S5 inhibited the phosphorylation of Akt, which is downstream of PI3Kδ, in concentration‐dependent manner. In view of the significant improvement in potency of PI3Kδ and selectivity over other PI3K isoforms, Compound S5 deserved further investigation as a promising PI3Kδ inhibitor. [ABSTRACT FROM AUTHOR]

In this study, new benzothiazole–pyrimidine hybrids (5a–c, 6, 7a–f, and 8–15) were designed and synthesised. Two different functionalities on the pyrimidine moiety of lead compound 4 were subjected to a variety of chemical changes with the goal of creating various functionalities and cyclisation to further elucidate the target structures. The potency of the new molecules was tested against different tuberculosis (TB) strains. The results indicated that compounds 5c, 5b, 12, and 15 (MIC = 0.24–0.98 µg/mL) are highly active against the first-line drug-sensitive strain of Mycobacterium tuberculosis (ATCC 25177). Thereafter, the anti-tubercular activity was evaluated against the two drug-resistant TB strains; ATCC 35822 and RCMB 2674, where, many compounds exhibited good activity with MIC = 0.98–62.5 3 µg/mL and 3.9–62.5 µg/mL, respectively. Compounds 5c and 15 having the highest anti-tubercular efficiency towards sensitive strain, displayed the best activity for the resistant strains by showing the MIC = 0.98 and 1.95 µg/mL for MDR TB, and showing the MIC = 3.9 and 7.81 µg/mL for XDR TB, consecutively. Finally, molecular docking studies were performed for the two most active compounds 5c and 15 to explore their enzymatic inhibitory activities. [ABSTRACT FROM AUTHOR]

Nanotechnology-based strategies can overcome the limitations of conventional cancer therapies. Hence, novel series of pyrimidine Schiff bases (4–9) were employed in the synthesis of selenium nanoparticle forms (4NPs–9NPs). All selenium nano-sized forms exerted greater inhibitions than normal-sized compounds, far exceeding 5-fluorouracil activity. Compound 4 showed effective anti-proliferative activity against MCF-7(IC50 3.14 ± 0.04 µM), HepG-2(IC50 1.07 ± 0.03 µM), and A549(IC50 1.53 ± 0.01 µM) cell lines, while its selenium nanoform 4NPs showed excellent inhibitory effects, with efficacy increased by 96.52%, 96.45%, and 93.86%, respectively. Additionally, 4NPs outperformed 4 in selectivity against the Vero cell line by 4.5-fold. Furthermore, 4NPs exhibited strong inhibition of CDK1(IC50 0.47 ± 0.3 µM) and tubulin polymerase(IC50 0.61 ± 0.04 µM), outperforming 4 and being comparable to roscovitine (IC50 0.27 ± 0.03 µM) and combretastatin-A4(IC50 0.25 ± 0.01 µM), respectively. Moreover, both 4 and 4NPs arrested the cell cycle at G0/G1 phase and significantly forced the cells towards apoptosis. Molecular docking demonstrated that 4 and 4NPs were able to inhibit CDK1 and tubulin polymerase binding sites. [ABSTRACT FROM AUTHOR]

A group of EGFR inhibitors derived from thieno[2,3-d]pyrimidine nucleus was designed, synthesised, and examined as anti-proliferative lead compounds. MCF-7 and A549 cell lines were inhibited by 5b, the most active member. It had inhibitory partialities of 37.19 and 204.10 nM against EGFRWT and EGFRT790M, respectively. Compound 5b was 2.5 times safer against the WI-38 normal cell lines than erlotinib. Also, it demonstrated considerable potentialities for both early and late apoptosis induction in A549. Simultaneously, 5b arrested A549's growth at G1 and G2/M phases. Harmoniously, 5b upregulated the BAX and downregulated the Bcl-2 genes by 3-fold and increased the BAX/Bcl-2 ratio by 8.3-fold comparing the untreated A549 cells. Molecular docking against EGFRWT and EGFRT790M indicated the correct binding modes. Furthermore, MD simulations confirmed the precise binding of 5b against the EGFR protein over 100 ns. Finally, various computational ADMET studies were carried out and indicated high degrees of drug-likeness and safety. [ABSTRACT FROM AUTHOR]

EGFR mutations have been identified in 20,000 reported NSCLC (non-small cell lung cancer) samples, and exon 19 deletions and L858R mutations at position 21, known as "classical" mutations, account for 85–90% of the total EGFR (epidermal growth factor receptor) mutations. In this paper, two series of EGFR kinase inhibitors were designed and synthesised. Among them, compound B1 showed an IC50 value of 13 nM for kinase inhibitory activity against EGFRL858R/T790M and more than 76-fold selectivity for EGFRWT. Furthermore, in an in vitro anti-tumour activity test, compound B1 showed an effective anti-proliferation activity against H1975 cells with an IC50 value of 0.087 μΜ. We also verified the mechanism of action of compound B1 as a selective inhibitor of EGFRL858R/T790M by cell migration assay and apoptosis assay. [ABSTRACT FROM AUTHOR]

Topoisomerases II are ubiquitous enzymes with significant genotoxic effects in many critical DNA processes. Additionally, epidermal growth factor receptor (EGFR) plays pivotal role in tumour growth and angiogenesis. A novel series of naphtho[2',3':4,5]thiazolo[3,2-a]pyrimidine hybrids have been designed, synthesised and evaluated for their topo IIα/EGFR inhibitory and apoptotic inducer activities. Cytotoxicity of the synthesised hybrids was evaluated against MCF-7, A549 and HCT-116 cell lines. Of the synthesised hybrids, 6i, 6a and 6c experienced superior cytotoxic activity compared to doxorubicin and erlotinib against the tested cancer cells. The molecular mechanism of these hybrids revealed their ability to successfully inhibit topo IIα and EGFR activities in micromolar concentration and may serve as topo II catalytic inhibitor. Moreover, these hybrids significantly arrested cell cycle at G2/M phase together with increased p53, caspae-7, caspase-9 levels and Bax/Bcl-2 ratio. The synthesised hybrids showed efficient binding pattern in molecular docking study and have acceptable drug likeness characters. [ABSTRACT FROM AUTHOR]

A novel series of multifunctional pyrazolo[3,4-d]pyrimidine-based glutamate analogs (6a–l and 7a,b) have been designed and synthesized as antifolate anticancer agents. Among the tested compounds, 6i exhibited the most potent anti-proliferative activity towards NSCLC, CNS, Ovarian, Prostate, Colon, Melanoma, Breast, and Renal cancers with good to weak cytostatic activity and non-lethal actions. 6i demonstrated higher selectivity for cancer than normal cells. 6i could significantly increase the accumulation of S-phase cells during the cell cycle distribution of cancer cells with high potency in the induction of apoptosis. The results unveiled that 6i probably acts through dual inhibition of DHFR and TS enzymes (IC50 = 2.41 and 8.88 µM, correspondingly). Docking studies of 6i displayed that N1-p-bromophenyl and C3-Methyl groups participate in substantial hydrophobic interactions. The drug-likeness features inferred that 6i met the acceptance criteria of Pfizer. Taking together, 6i could be a promising prototype for further optimization as an effective anticancer drug. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

To explore the potential use of CDK inhibitors in pancreatic ductal adenocarcinoma (PDAC) therapy, a series of novel 2-((4-sulfamoylphenyl)amino)-pyrrolo[2,3-d]pyrimidine derivatives was designed, synthesised, and investigated for inhibition on both CDK kinase activity and cellular proliferation of pancreatic cancer. Most of new sulphonamide-containing derivatives demonstrated strong inhibitory activity on CDK9 and obvious anti-proliferative activity in cell culture. Moreover, two new compounds suppressed cell proliferation of multiple human pancreatic cancer cell lines. The most potent compound 2g inhibited cancer cell proliferation by blocking Rb phosphorylation and induced apoptosis via downregulation of CDK9 downstream proteins Mcl-1 and c-Myc in MIA PaCa-2 cells. CDK9 knockdown experiment suggests its anti-proliferative activity is mainly mediated by CDK9. Additionally, 2g displayed moderate tumour inhibition effect in AsPC-1 derived xenograft mice model. Altogether, this study provided a new start for further optimisation to develop potential CDK inhibitor candidates for PDAC treatment by alone or combination use. [ABSTRACT FROM AUTHOR]

A novel series of 12 antipyrine derivatives containing 1,3,4-oxadiazoles (4a-d), 1,3,4-thiadiazoles (6a-d), and pyrimidines (8a-d), was preparedand assessed for its potential in vitro COX-2 inhibitors. Compared to Celecoxib, compounds 4b-d and 8d were the most potent derivatives c with a half-maximal inhibitory concentration range of 53–69 nM. Considering COX-2 selectivity index, compounds 4 b and 4c were chosen among these most potent derivatives for further investigation. The in vivo ability of compounds 4 b and 4c to counteract carrageenan-induced paw edoema has been assessed and their potential underlying mechanisms have been elucidated and the results have been further validated using molecular docking simulations. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the antitumor effect of simultaneous inhibition of dihydrofolate reductase (DHFR) enzyme. We designed some novel pyrazolo[3,4-d]pyrimidines bearing different amino acid conjugates as efficient antifolate agents attributable to their structural similarity with methotrexate (MTX) and MTX-related antifolates. All compounds were tested to screen their enzymatic inhibition against DHFR compared with the reference drug MTX and for their in vitro antitumor cytotoxicity against six MTX-resistant cancer cell lines. The flow cytometry indicated that the most potent compound 7f arrested MCF-7 cells in the S-phase and induced apoptosis. Western blot for visualisation proved the ability of compound 7f to induce the expression of proapoptotic caspases and Bax proteins in MCF-7 breast cancer cell line beside its ability to diminish the expression of antiapoptotic Bcl-2 protein. Molecular modelling studies concluded that compound 7f displayed better binding energy than that of the normal ligand MTX. New pyrazolo[3,4-d]pyrimidine derivatives 7a–m which are structurally similar to the classical methotrexate (MTX) and MTX-related antifolates were synthesised as antitumor agents. Novel N-acyl amino acid compound 7f exhibited marked DHFR inhibition activity that are parralel to both the molecular docking results and cytotoxic activity. Compound 7f could induce the expression of proapoptotic caspases and Bax proteins in MCF-7 breast cancer cell line beside its ability to diminish the expression of antiapoptotic Bcl-2 protein. All prepared compounds obey Lipinski rule of five except compound 7f. [ABSTRACT FROM AUTHOR]

An efficient, one pot, multicomponent, L‐arginine catalyzed synthesis of thiazolo[3,2‐a]pyrimidines is described. L‐arginine is an easily available, biodegradable, inexpensive, promising bio‐organic molecule. The current strategy is the first example of amino acid promoted, green synthesis of a series of thiazolo[3,2‐a]pyrimidines via the formation of CN and CC bonds. The major advantages of the present methodology such as recyclability of catalyst, operational simplicity, easy scale‐up, wide substrate scope, easy work‐up, inexpensive, excellent yields, and high atom economy make it a distinct improvement over the prevailing strategies. [ABSTRACT FROM AUTHOR]

This article discusses the synthesis of pyrido[2,3-d]pyrimidines, which are important heterocycles found in many pharmaceutically active molecules. The traditional methods for synthesizing these compounds are described, as well as the limitations of these methods. The article then presents a new catalytic system using 2,3-Dichloro-5,6-dicyano-1,4-benzoquinone (DDQ)/tert-Butyl Nitrite (TBN)/O2 for the synthesis of pyrido[2,3-d]pyrimidines. The reaction conditions and optimization are discussed, and the results show promising yields. This research provides a new and efficient method for the synthesis of pyrido[2,3-d]pyrimidines with potential bioactivities. The given document presents a table showing the results of control experiments on the reaction of uracils and 1,3-diarylpropenes. The table includes entries for different combinations of reactants and the corresponding products and yields. The experiments indicate that both TBN and O2 promote the reaction. The table provides specific details about the reactants and products, as well as the corresponding yields. This document describes a novel and efficient method for synthesizing pyrido[2,3-d]pyrimidines/thiopyrido[2,3-d]pyrimidines using easily available starting materials. The reaction involves oxidative coupling, intramolecular cyclization, [Extracted from the article]

Nucleoside analogues are prevalent in drug design and call for more diversified structures. Bicyclo[1.1.1]pentane (BCP) structure has recently found wide applications in drug discovery. However, incorporation of BCP fragment into nucleoside analogues is hitherto unknown. Thus, from readily available BCP-containing building blocks, six new compounds, including pyrimidine nucleoside analogues, purine nucleoside analogues, and C-nucleoside analogues were prepared in 1–4 steps, generally with good yields. [ABSTRACT FROM AUTHOR]

The present study deals with a highly efficient and regioselective synthesis of 7-aryl-5-methyl- and 5-aryl-7-trifluoromethyl-2-amino-3-(4′-arylazo)-pyrazolo[1,5-a]pyrimidines via multicomponent reaction of hydrazine hydrate, 2-(arylhydrazono)malononitrile and β-diketones in presence of p-toluenesulphonic acid under solvent-free condition. The structure of the isolated products was established on the basis of NMR (1H, 13C, and 19F) and IR spectral data. The scope of the reaction was studied using various β-diketones viz., aliphatic, aromatic, heteroaromatic, and trifluoromethyl-β-diketones. The protocol has several advantages, such as mild conditions, atom economy, practical simplicity, shorter reaction times, and avoidance of multi-step procedures. Seventeen diversely substituted pyrazolo[1,5-a]pyrimidines were screened against two breast cancer cell lines, named MCF-7 and BT474, and two leukemia cell lines, named NALM-6 and SB-ALL, using the MTT cytotoxicity assay. Preliminary results reveal that compound 2-amino-5-(4-bromophenyl)-3-(4-methoxyphenylazo)-7-(trifluoromethyl)pyrazolo[1,5-a]pyrimidine was identified as the most effective compound against all the four cancer cell lines with 65-49% cell survival. An efficient regioselective synthesis of 7-aryl-5-methyl- and 5-aryl-7-trifluoromethyl-2-amino-3-(4′-arylazo)-pyrazolo[1,5-a]pyrimidines is developed using solvent-free sequential multicomponent reaction of hydrazine hydrate, 2-(arylhydrazono)malononitrile with unsymmetrical β-diketones. [ABSTRACT FROM AUTHOR]

A lead aryl pyrrolidinone anilide identified using high-throughput in vivo screening was optimized for efficacy, crop safety, and weed spectrum, resulting in tetflupyrolimet. Known modes of action were ruled out through in vitro enzyme and in vivo plant-based assays. Genomic sequencing of aryl pyrrolidinone anilide-resistant Arabidopsis thaliana progeny combined with nutrient reversal experiments and metabolomic analyses confirmed that the molecular target of the chemistry was dihydroorotate dehydrogenase (DHODH), the enzyme that catalyzes the fourth step in the de novo pyrimidine biosynthesis pathway. In vitro enzymatic and biophysical assays and a cocrystal structure with purified recombinant plant DHODH further confirmed this enzyme as the target site of this class of chemistry. Like known inhibitors of other DHODH orthologs, these molecules occupy the membrane-adjacent binding site of the electron acceptor ubiquinone. Identification of a new herbicidal chemical scaffold paired with a novel mode of action, the first such finding in over three decades, represents an important leap in combatting weed resistance and feeding a growing worldwide population. [ABSTRACT FROM AUTHOR]

We present a study on a new class of Schiff bases with pyrimidine linked hydrazinyl azole backbone. These compounds were synthesized using conventional and ultrasonication methods. Our design strategy incorporated three heteroaromatic azoles and various substituents on the pyrimidine scaffold to enhance antimicrobial properties. Antibacterial and antifungal screenings were conducted against specific pathogens, and molecular docking studies supported the results. The compounds exhibited significant antimicrobial activities, particularly against K. pneumoniae, surpassing the standard drug. These Schiff bases hold promise as potential antimicrobial agents. [ABSTRACT FROM AUTHOR]

The pyrido[1,2‐a]pyrimidine scaffold has great potential for the creation of bioactive substances. Here we propose a simple, cost‐effective, efficient approach to forming this core based on a one‐pot three‐component reaction of commercially available 3‐oxo esters, α,β‐unsaturated aldehydes and 1,3‐diaminopropane. The developed strategy makes it possible to obtain diverse pyrido[1,2‐a]pyrimidines thanks to alternative intramolecular cyclization pathways that depend on the substituent in the 3‐oxo ester. Their diastereomeric structure was determined using NMR spectroscopy and XRD. A mechanism for the formation of new pyrido[1,2‐a]pyridines has been proposed. [ABSTRACT FROM AUTHOR]

Quinazoline derivatives, as an important category of heterocyclic compounds, have received much attention for the design and development of new drugs due to their various pharmacological properties. Besides, there is a great deal of evidence showing pyrimidine analogs as anticancer agents. Thus, in the present study, for the design of new target compounds with cytotoxic activity, we focused on various quinazolinone and pyrimidine hybrids. A new series of quinazoline-pyrimidine hybrid derivatives (6a-6n) have been designed and synthesized as novel antiproliferative agents. All the synthesized compounds characterized based on their IR, NMR and Mass spectroscopic data. Antiproliferative activities of the new compounds were evaluated against three human cancer cell lines (MCF-7, A549, SW-480). The compounds were found to have appropriate potential with IC50 values ranging from 2.3 ± 5.91 to 176.5 ± 0.7 μM against the tested cell lines. Compound 6n exerted the highest antiproliferative activity with IC50 values of 5.9 ± 1.69 μM, 2.3 ± 5.91 μM and 5.65 ± 2.33 μM against A549, SW-480 and MCF-7 respectively. The results indicated that 6n could induce apoptosis in A549 cell line in a dose dependent manner and arrest in the S phase of cell cycle. Docking studies were also done to investigate the detailed binding pattern of the synthesized compounds against EGFR. Furthermore, molecular dynamic simulation and binding free energy calculation have been done to rescore initial docking pose of the synthesized compounds using ensemble-based MMGB/PBSA free energy method. According to the results, free energy calculation confirmed biological activity of compounds and also, Arg 817 and Lys 721 residues had the pivotal role in the high potency of 6n. Finally, the drug likeness and in silico ADME study were also predicted. [ABSTRACT FROM AUTHOR]

Utilizing the Knoevenagel–Michael tandem cyclocondensation reaction of barbituric acid/1,3-dimethylbarbituric acid, malononitrile, and aryl aldehydes, a sustainable methodology for the photosynthesis of pyrano[2,3-d]pyrimidine scaffolds has been devised. The present study expounds on the development of a green radical synthetic approach toward this class of compounds. In this study, a novel halogenated dicyanobenzene-based photosensitizer was utilized in an aqueous solution, exposed to air at room temperature, and activated by a blue LED as a renewable energy source for the purpose of generating energy. The primary aim of this endeavor is to employ a recently developed, easily obtainable, and affordably priced halogenated cyanoarene-based donor–acceptor (D–A). The 3DPAFIPN [2,4,6-tris(diphenylamino)-5-fluoroisophthalonitrile]} photocatalyst, as a thermally activated delayed fluorescence (TADF), is capable of inducing single electron transfer (SET) upon irradiation with visible light, thereby offering a facile and efficient approach with a high degree of effectiveness, energy efficiency, and eco-friendliness. The aforementioned phenomenon facilitates the exploration of the temporal changes that have occurred in the interactions between the surroundings and chemical constituents. The present study aimed to investigate the turnover number (TON) and turnover frequency (TOF) for pyrano[2,3-d]pyrimidine scaffolds. Additionally, it has been demonstrated that gram-scale cyclization is a viable method for utilization in industrial applications. [ABSTRACT FROM AUTHOR]