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We report three new polymers, based on mechanically interlocked inorganic–organic rotaxanes. They are made in very mild conditions and involve pyrimidine head groups binding to copper(ii) linking units. A two-dimensional 6,3 net and a three-dimensional 10,3b net are found depending on the solvent used in the reaction. [ABSTRACT FROM AUTHOR]

In this paper for the first time, we report a simple one-step synthesis of 5-methyl-11,12-dihydro-5 H -5,11-epoxybenzo[7,8]oxocino[4,3- d ]pyrimidine derivatives by acid-catalyzed cyclization reaction of various 4-methyl-5-acetyl pyrimidine derivatives with salicylic aldehyde. It was shown that 2-substituted 4-methyl-5-acetylpyrimidines successfully react to form a cyclization product. At the same time, 4-methyl-5-acetylpyrimidines with a substituent in the 6th position do not enter into the cyclization reaction. This may be caused by the negative effect of substituents in the 6th position, which hinder the free rotation of the acetyl group and prevent the formation of a stable pre-reaction complex. The structures of the obtained 5-methyl-11,12-dihydro-5 H -5,11-epoxybenzo[7,8]oxocino[4,3- d ]pyrimidine derivatives were confirmed using1 H NMR and13 C NMR spectroscopy, mass spectrometry, and X-ray diffraction analysis. [ABSTRACT FROM AUTHOR]

This article presents an efficient one-step synthesis of tetrahydropyrazolo[1,5- a ]pyrimidines through the recyclization of N -arylitaconimides with aminopyrazoles. The heterocyclic system of pyrazolo[3,4- b ]pyrimidine is known for its diverse biological properties, making its derivatives significant in pharmaceutical and medicinal chemistry. The study focuses on the regio- and chemoselective cascade reaction of N -arylitaconimides with 5-aminopyrazoles, demonstrating a new approach to synthesizing pyrazolo[1,5- a ]pyrimidines and pyrazolo[3,4- b ]pyridines. The methodology, involving boiling in isopropyl alcohol with acetic acid, yields selectively either pyrazolo[3,4- b ]pyridines or pyrazolo[1,5- a ]pyrimidines based on the substituents in the aminopyrazoles. The study elucidates the reaction mechanism, structural characterization using NMR spectroscopy, and confirms the structures via high-performance liquid chromatography and mass spectrometry. The simplicity and synthetic potential of this approach make it a valuable method for the preparation of these heterocyclic frameworks. [ABSTRACT FROM AUTHOR]

The pyrimidine heterocycle plays an important role in anticancer research. In particular, the pyrimidine derivative families of uracil show promise as structural scaffolds relevant to cervical cancer. This group of chemicals lacks data-driven machine learning quantitative structure-activity relationships (QSARs) that allow for generalization and predictive capabilities in the search for new active compounds. To achieve this, a dataset of pyrimidine and uracil compounds from ChEMBL were collected and curated. A workflow was developed for data-driven machine learning QSAR using an intuitive dataset design and forwards selection of molecular descriptors. The model was thoroughly externally validated against available data. Blind validation was also performed by synthesis and antiproliferative evaluation of new synthesized uracil-based and pyrimidine derivatives. The most active compound among new synthesized derivatives, 2,4,5-trisubstituted pyrimidine was predicted with the QSAR model with differences of 0.02 compared to experimentally tested activity. [ABSTRACT FROM AUTHOR]

This article discusses the design, synthesis, and evaluation of amide derivatives of thienopyrimidine isoxazoles for their anticancer properties. The researchers synthesized a library of compounds and tested their anticancer activities against four different cancer cell lines. Two compounds, 13a and 13e, showed particularly promising results. Molecular docking analysis revealed the key interactions of the compounds with the target protein, ATR kinase. The document also describes the synthesis, characterization, and cytotoxic activity testing of several other compounds, as well as the methods used for molecular docking studies. The study was financially supported by the Deanship of Scientific Research, King Khalid University, and no conflicts of interest were reported by the authors. [Extracted from the article]

In this study, we introduce a novel porous metal–organic framework named Co2(bbda)2(DMF)2·5H2O, or MOF‐UoR‐1, synthesized via hydrothermal techniques employing a unique Schiff base ligand. The framework underwent comprehensive characterization, confirming its microporous nature through gas‐sorption measurements. MOF‐UoR‐1 demonstrated remarkable efficacy as a catalyst for the one‐step synthesis of pyrimidine analogs. Structural validation of the synthesized pyrimidines was accomplished via 1H‐nuclear magnetic resonance (NMR) and Fourier transform infrared (FTIR) analyses. Through systematic experimentation, the optimal catalyst dosage (40 mg) was determined, showcasing its effectiveness across various aldehydes, 1,3‐carbonyl compounds, and urea substrates. Noteworthy is the broad applicability of this environmentally friendly protocol, which offers advantages such as high yields (96%), rapid reaction times (90 min), straightforward product isolation, and product purity without necessitating column chromatography. Furthermore, the catalytic integrity of the framework remained intact, enabling its reuse without compromising performance. This research presents a promising approach for the synthesis of pyrimidine derivatives, with significant implications for sustainable and efficient chemical synthesis methodologies. [ABSTRACT FROM AUTHOR]

2‐Amino pyrimidines are vital molecules that exhibit diverse biological activities and serve as structural motifs in various pharmaceutical drugs. Four new series of triazole‐linked glycohybrids of 2‐amino‐pyrimidinones were designed and efficiently synthesized, using a microwave‐assisted method under click chemistry reaction conditions. The N‐propargyl‐2‐aminopyrimidinone and O‐propargyl‐2‐aminopyrimidine derivatives successfully underwent the click reactions with 1‐azido‐tetra‐O‐acetyl‐β‐D‐glucose, D‐galactose and D‐mannose. In this work, we reported the series of novel thirty‐three new triazole‐linked glycohybrid molecules with stereochemical diversity and diverse substitution patterns. [ABSTRACT FROM AUTHOR]

Worldwide, colorectal cancer (CRC) is the third most common type of cancer and the second most common cause of cancer-related deaths. Thymidylate synthase (TS) is a crucial component of DNA biosynthesis and has drawn interest as an essential target for cancer treatment. In the current work, we have designed and synthesized twenty-eight new diaryl-based pyrido[2,3-d]pyrimidine/alkyl-substituted pyrido[2,3-d]pyrimidine derivatives and evaluated their anticancer activity against the HCT 116, MCF-7, Hep G2, and PC-3 cell lines cell lines. Additionally, we have carried out TS inhibitory activity and in silico studies for compounds 1n and 2j. All the synthesized compounds exhibited good anticancer activity, but among them, compounds 1n and 2j showed excellent anticancer activity, having IC50 values of 1.98 ± 0.69, 2.18 ± 0.93, 4.04 ± 1.06, and 4.18 ± 1.87 µM; and 1.48 ± 0.86, 3.18 ± 0.79, 3.44 ± 1.51, and 5.18 ± 1.85 µM, against the HCT 116, MCF-7, Hep G2, and PC-3 cell lines respectively with control raltitrexed (IC50 1.07 ± 1.08, 1.98 ± 0.72, 1.34 ± 1.0, and 3.09 ± 0.96 µM, respectively) and hTS inhibitory activity with IC50 values of 20.47 ± 1.09 and 13.48 ± 0.96 nM with control raltitrexed (IC50 14.95 ± 1.01 nM). Further, the mechanism of inhibition was revealed by molecular docking, which showed the binding pattern of 1n and 2j to the catalytic site of TS with docking scores of -10.6 and − 9.5 kcal/mol, respectively, with reference raltitrexed (-9.4 kcal/mol). Additionally, the assessment of physicochemical, biochemical, structural, and toxicological characteristics were also in the acceptable range for these compounds. Based on the anticancer activity of compounds, SAR was also performed for lead optimization. [ABSTRACT FROM AUTHOR]

A gentisic acid based-Deep Eutectic Solvent (MTPPBr/GA-DES) was synthesized by mixing one mole of methyl triphenylphosphonium bromide (MTPPBr) and one mole of gentisic acid (GA: 2,5-dihydroxy-benzoic acid) based on the eutectic point phase diagram. Then, it was characterized by FT-IR, NMR, densitometer, and TGA/DTA techniques and used as a potent and novel catalyst for the fast and green synthesis of: (i) Five new 2(a-e) and five known 2(f-j) benzo[6,7]chromeno[2,3-d]pyrimidines and (ii) One new (3a) and eleven known 3(b-l) pyrano[2,3-d]pyrimidines, in solvent-free conditions, short reaction times, and high yields. It is important to mention that for the synthesis of 2(a-j), there is only one reference which states that the reaction times are extremely long (720–2400 min), while these times are reduced to approximately 35–50 min in our proposed strategy, indicatinging that the rate of reactions will be 20–48 times faster, which is the clear and most obvious advantage of our approach. [ABSTRACT FROM AUTHOR]

The relevance of the asymmetric Biginelli reaction (ABR) has been increased in this century, due to the pharmacological application of its products. This review focuses predominantly on articles published in the period from 2015 to 2024 on asymmetric synthetic advances in the formation of dihydropyrimidinones (DHPMs), dihydropyrimidinethiones (DHPMTs), and related compounds. The relevant bibliography on general processes in the Biginelli reaction and some methods of separation of isomers have also been referenced. [ABSTRACT FROM AUTHOR]

In this work, a series of new diarylpyrimidine derivatives as microtubule destabilizers were designed, synthesized, and evaluated for anticancer activities. Based on restriction configuration strategy, we introduced the pyrimidine moiety containing the hydrogen-bond acceptors as c/s-olefin bond of CA-4 analogs to improve structural stability. Compounds 11a-t exerted antiproliferative activities against three human cancer cell lines (SGC-7901, HeLa, and MCF-7), due to tubulin polymerization inhibition, showing high selectivity toward cancer cells in comparison with non-tumoral HSF cells, as evidenced by MTT assays. In mechanistic investigations, compound 11s remarkably inhibited tubulin polymerization and disorganized microtubule in SGC-7901 cells by binding to tubulin. Moreover, 11s caused G2/M phase cell cycle arrest in SGC-7901 cells in a concentration-dependent manner. Furthermore, molecular modeling analysis revealed that 11s interacts with tubulin through binding to the colchicine site. In addition, the prediction of physicochemical properties disclosed that 11s conformed well to the Lipinski's rule of five. This work offered a fresh viewpoint for the discovery of new tubulintargeting anticancer drugs. [ABSTRACT FROM AUTHOR]

Iron(III)- and iodide-promoted efficient synthesis of pyrimidines from biomass-based alkyl lactates, inorganic ammonium, and aldehydes was carried out. This multicomponent reaction efficiently proceeded through a series of condensation, dehydrogenation coupling, and condensation steps to form C–N and C–C bonds, respectively. This protocol strikingly features sustainable catalysis using Earth-abundant metals and NH4I as a substrate and catalyst. When using biomass-based alkyl lactate as a raw material, the alkyl lactate can be reused, and clean byproducts can be obtained. More than 30 pyrimidines and 7 triazines were synthesized in isolated yields of up to 92%. In addition, the analysis of several dimensions of green indicators proves the greenness of this work. Promising applications of biobased alcohols and inorganic salts in sustainable organic synthesis are represented by this work. [ABSTRACT FROM AUTHOR]

Inhibition of sodium-glucose cotransporter 2 (SGLT2) by empagliflozin (EMPA) and other “flozins” can improve glycemic control under conditions of diabetes and kidney disease. Though they act on the kidney, they also offer cardiovascular and liver protection. Previously, we found that EMPA decreased circulating triglycerides and hepatic lipid and cholesterol esters in male TallyHo mice fed a high-milk-fat diet (HMFD). The goal of this study was to determine whether the liver protection is associated with a change in metabolic function by characterizing the hepatic and circulating metabolic and lipidomic profiles using targeted LCMS. In both male and female mice, HMFD feeding significantly altered the circulating and hepatic metabolome compared with low-fat diet (LFD). Addition of EMPA resulted in the restoration of circulating orotate (intermediate in pyrimidine biosynthesis) and hepatic dihydrofolate (intermediate in the folate and methionine cycles) levels in males and acylcarnitines in females. These changes were partially explained by altered expression of rate-limiting enzymes in these pathways. This metabolic signature was not detected when EMPA was incorporated into an LFD, suggesting that the restoration requires the metabolic shift that accompanies the HMFD. Notably, the HMFD increased expression of 18 of 20 circulating amino acids in males and 11 of 20 in females, and this pattern was reversed by EMPA. Finally, we confirmed that SGLT2 inhibition upregulates ketone bodies including b-hydroxybutyrate. Collectively, this study highlights the metabolic changes that occur with EMPA treatment, and sheds light on the possible mechanisms by which this drug offers liver and systemic protection. NEW & NOTEWORTHY Sodium-glucose cotransporter 2 (SGLT2) inhibitors, including empagliflozin, have emerged as a new treatment option for individuals with type 2 diabetes that have positive impacts on kidney and cardiovascular disease. However, less is known about their impact on other tissues, including the liver. Here, we report that empagliflozin reduces hepatic steatosis that is associated with restoring metabolic intermediates in the folate and pyrimidine biosynthesis pathways. These changes may lead to new approaches to treat nonalcoholic fatty liver disease. [ABSTRACT FROM AUTHOR]

Tropomyosin receptor kinases (Trks) are transmembrane receptor tyrosine kinases named TrkA, TrkB, and TrkC and encoded by the NTRK1, NTRK2, and NTRK3 genes, respectively. These kinases have attracted significant attention and represent a promising therapeutic target for solid tumor treatment due to their vital role in cellular signaling pathways. First-generation TRK inhibitors, i.e., Larotrectinib sulfate and Entrectinib, received clinical approval in 2018 and 2019, respectively. However, the use of these inhibitors was significantly limited because of the development of resistance due to mutations. Fortunately, the second-generation Trk inhibitor Repotrectinib (TPX-0005) was approved by the FDA in November 2023, while Selitrectinib (Loxo-195) has provided an effective solution to this issue. Another macrocycle-based analog, along with many other TRK inhibitors, is currently in clinical trials. Two of the three marketed drugs for NTRK fusion cancers feature a pyrazolo[1,5-a] pyrimidine nucleus, prompting medicinal chemists to develop numerous novel pyrazolopyrimidine-based molecules to enhance clinical applications. This article focuses on a comprehensive review of chronological synthetic developments and the structure–activity relationships (SAR) of pyrazolo[1,5-a]pyrimidine derivatives as Trk inhibitors. This article will also provide comprehensive knowledge and future directions to the researchers working in the field of medicinal chemistry by facilitating the structural modification of pyrazolo [1,5-a]pyrimidine derivatives to synthesize more effective novel chemotherapeutics as TRK inhibitors. [ABSTRACT FROM AUTHOR]

Four novel Pd (II), Cu (II), VO (II), and Ag(I) complexes were prepared from benzimidazole ligand through bidentate chelating mode. Alternative spectral and analytical tools were applied to elucidate their structural and molecular formulae. This study was extended to investigate stability and stoichiometry of complexes in solution, using standard methods. In addition, the best atomic distribution within structural forms was obtained via the density functional theory (DFT) method. This computational study fed us with significant physical characteristics for differentiation. Also, DFT/time‐dependent DFT computations were performed applying (B3LYP/6‐311++G[d,p]/aug‐cc‐pVTZ/aug‐cc‐pVTZ‐PP) level in order to investigate the electronic behavior of the compounds. These results demonstrated good agreement with the experimental data. Computational data discriminate Pd (II) complex by some physical features, which may be promising in the catalytic field. This complex was selected to play a catalytic function to synthesize 3‐methyl‐4‐phenyl‐4,9‐dihydro‐1H‐pyrazolo[3,4‐d][1,2,4]triazolo[1,5‐a]pyrimidine derivatives using microwave irradiation in a one‐pot reaction. The catalyst was selected for this application based on the history of Pd (II) complexes and the properties expected theoretically. A condensation reaction for 3‐methyl‐5‐pyrazolone, aromatic aldehyde, and 5‐aminotetrazole was carried out under mild reaction conditions by microwave irradiation. All reaction conditions were optimized among those variable Lewis acid catalysts in comparison with our new complexes. DOBPAPd catalyst displayed superiority in overall trials with high yield, short time, and green conditions (solvent H2O/EtOH). Also, the recovery of hetero catalyst was succeeded and reused by the same efficiency up to five times after that the efficiency was reduced. The mechanism of action was proposed based on the ability of Pd (II) for adding extra‐bonds over z‐axis and supported by theoretical aspects. [ABSTRACT FROM AUTHOR]

2,4,6‐Triamino‐N‐phenylpyrimidine‐5‐carbothioamide (LPH) was synthesized and extensively characterized. Single crystal X‐ray confirms a monoclinic P21/c space group for LPH. The novel ligand and its chelates of Cr3+, Ni2+, and Ru3+ were studied by elemental analyses, spectral (13C‐,1H‐NMR, UV–visible, IR), magnetic, and thermal measurements. IR spectra indicated that LPH behaves in a bidentate mode through the two NH2 groups of the pyrimidine ring and/or a tetradentate coordination involving the nitrogen atoms of the two NH2 of the pyrimidine ring, NH, and the thioketo (C=S) groups, respectively. By utilizing the Gaussian 09 W program in DFT/B3LYP, we are able to conduct computational estimates of LPH and its metal chelates, yielding insightful data regarding their electronic structure and stability. Biological studies were conducted to assess the isolated compounds' activities against anticancer (MCF‐7), antioxidant (DPPH and ABTS), DNA, and antimicrobial proteins. Molecular docking was employed to investigate the chelates' inhibitory properties, specifically their binding propensity with MCF‐7 cells, revealing possible anticancer action. All the data help to understand LPH and its complexes' production, biological characteristics, and possible therapeutic uses. [ABSTRACT FROM AUTHOR]

Eleven new differently substituted N,7-diphenylpyrimido [4,5-d]pyrimidin-4-amines 4a–k were synthesized from readily available reagents in a simple and inexpensive two-step procedure with yields up to 57%. Neuroprotective analysis against H2O2 and analysis using ORAC assays identified compounds 4g, 4i and 4j as promising antioxidant compounds. These compounds also showed potent inhibition of Aβ1–42 self-aggregation, and suitable physicochemical properties predicted by Datawarior software V6.1.0, this biological activity and physicochemical property being of great interest for pathologies linked to oxidative stress, such as Alzheimer's disease. [ABSTRACT FROM AUTHOR]

A novel Deep Eutectic Solvent (MTPPBr/HGA-DES) was prepared by a mixture of methyl triphenylphosphonium bromide (MTPPBr) and hypogallic acid (HGA: 2,3-dihydroxybenzoic acid). The eutectic point phase diagram showed that the one mole of MTPPBr to two moles of HGA is the best mole ratio for the synthesis of a novel DES. Then, MTPPBr/HGA-DES was characterized by the FT-IR, TGA/DTA, densitometer, eutectic points, and 1H NMR techniques, and used as a novel catalyst for the green synthesis of new pyrano[2,3-d]pyrimidines 2(a-j)via a one-pot four-component condensation reaction of 4-hydroxycoumarin, barbituric acid, morpholine and benzaldehydes at 80 °C in solvent-free conditions. [ABSTRACT FROM AUTHOR]

Machine learning (ML) approaches have been developed to predict materials' corrosion inhibition efficiency, particularly pyrimidine compounds. Notably, the virtual sample generation (VSG) technique enhances prediction accuracy, a novel approach for handling small datasets in this context. The random forest model, the best-performing nonlinear algorithm, showed substantial accuracy improvement based on the increase in R2 value from 0.05 to 0.99 and the decrease in RMSE value from 5.60 to 0.42, after applying VSG. These results underscore the efficacy of the VSG technique in boosting the predictive performance of ML models, particularly in scenarios constrained by limited data availability. [ABSTRACT FROM AUTHOR]

Indoles and their derivatives have long been studied for their anticancer properties. Breast cancer has been treated using indole‐3‐carbinol, Indirubins, and many other naturally occurring indoles as well as their synthesized equivalents. It has been determined that the AKT pathway is a prospective target for therapeutic strategies in the treatment of breast cancer. The dysregulation of AKT pathway frequently promotes cell proliferation, survival, and resistance to apoptosis. We synthesized a novel group of bisindole clubbed pyridine and pyrimidine derivatives 5(a–l) using water as the solvent and thiamine hydrochloride as the catalyst. Compounds 5 a, 5 c, 5 d, 5 e, and 5 f are the most active against MCF‐7 cells, with an IC50 values of 2.48±0.39, 1.35±0.13, 3.36±0.53, 4.05±0.61 and 1.91±0.28 μM, respectively. Further, in silico docking of the active compound 5 c had the highest binding energy of −10.59 kcal/mol. Additionally, molecular dynanamics simulations were performed for better understanding the mode of interaction of ligand and protein. In conclusion, we have synthesized bisindoles using thiamine hydrochloride as a catalyst that target AKT pathway in breast cancer cells. [ABSTRACT FROM AUTHOR]

Chromenes are an essential class of oxygen‐containing heterocyclic compounds with intriguing biological activity. It is an important moiety for the discovery of new drug candidates. Chromenes are naturally abundant as alkaloids, tocopherols, flavones, and anthocyanins. The incorporation of 4H‐chromene, along with various bioactive heterocycles such as indole, pyrazole, kojic acid, pyran‐2‐one, quinoline, pyridine, pyrimidine, coumarin, sesamol, furan, uracil, benzoimidazole, benzotriazole, thiazole, isoxazole and barbituric acid moieties, into a molecular scaffold has the potential to combine the properties of both components. The synergistic effect of combining different heterocyclic moieties within a 4H‐chromene nucleus results in the formation of valuable compounds with significant biological importance. This review summarizes the different synthetic techniques used for preparing 4H‐chromene‐embedded heterocycles. The common mechanisms of key reactions and the significance of the method are discussed. [ABSTRACT FROM AUTHOR]

Pyrimidine and its derivatives play a paramount role in drug discovery as privileged pharmacophores with considerable chemical and biological significance and its presence in genes. This review aims to assemble a systematic evaluation of synthetic tactics of various fused pyrimidine derivatives containing nitrogen heterocycles such as pyridopyridines, pyridopyrimidines, and pyrimidopyrimidine from a pharmacological point of view and deliver an overview of methodologies presenting the chemistry of fused pyrimidine derivatives. The review details the importance of various catalysts and ring substitution using various electrophilic and nucleophilic reagents. These synthetic strategies were elaborated based on the different synthetic routes that lead to the specific type of pyrimidine and pyridine fused derivatives. The literature accumulates various developments in one‐pot condensation, the Knoevenagel–Michael addition mechanism, microwave and ultrasound irradiation, intramolecular cyclization, nano‐catalytic reactions, and so forth. Short reaction times, catalyst reusability, solvent‐free conditions, excellent yields, and stereo‐selectivity are some of the benefits of certain synthetic approaches. [ABSTRACT FROM AUTHOR]

The New Journal of Chemistry, published by The Royal Society of Chemistry, has released its latest issue containing a variety of articles on different topics in chemistry. The articles cover subjects such as photophysicochemical properties, synthesis of novel compounds, and catalytic reactions. Some specific topics explored in the papers include the synthesis of fluorescent compounds, structural dynamics of phosphorus-containing diesters, emission properties of glass ceramics, and the influence of different cations on spectral properties. Other papers discuss luminescence in lead-free perovskites, synthesis of materials for supercapacitors, photocatalytic activities of nanocomposites, and the adsorption and separation of composite pollutants. The journal aims to connect the world with the chemical sciences. [Extracted from the article]

In this report, we show that a very common modification (especially in tRNA), dihydrouridine, was efficiently produced by photoreduction of the canonical pyrimidine ribonucleoside, uridine in formamide. Formamide not only acts as a solvent in this reaction, but also as the reductant. The other three components of the canonical alphabet (C, A, G) remained intact under the same conditions, suggesting that dihydrouridine might have coexisted with all four canonical RNA nucleosides (C, U, A, G) at the dawn of life. [ABSTRACT FROM AUTHOR]

The present study mainly focused on synthesizing novel triazolo[1,5‐a]pyrimidine‐6‐carboxamide derivatives using multicomponent reaction. Synthesized derivatives were duly characterized using spectroscopic methods of analysis FT‐IR and mass spectroscopy, and 1H NMR and 13C NMR confirmed the structure of compounds. Further, the potential of the synthesized compounds against Plasmodium falciparum dihydrofolate reductase (Pf‐DHFR) inhibitors was evaluated by in vitro antimalarial activity, and the results of the study showed moderate to good antimalarial profile of synthesized entities. In silico study of all the synthesized compounds was carried out using Schrödinger LLC‐2020‐3 Software to explain the binding mode and interactions between molecules and pf DHFR enzyme. To study the drug likeliness of molecules, 3D QSAR and Pharmacokinetic studies have been carried out, and the results obtained showed a good pharmacokinetics profile of two compounds, namely AMP‐24 and AMP‐28, having good IC50 values concerning standard drugs. Further, the in vitro enzyme inhibition assay results suggested that the synthesized compound interacts nicely with the enzyme and might be used as a potent antimalarial agent. [ABSTRACT FROM AUTHOR]

The histone deacetylases (HDACs) are being explored as a promising therapeutic target for the treatment of various diseases. Here, the synthesis of a series of pyrimidine‐based 1,3,4‐oxadiazoles, in which the oxadiazole scaffold is attached to the pyrimidine ring via a methyleneoxy spacer, is described and their HDAC inhibitory activity studied. The target compounds were synthesized by sequence of reactions involving O‐alkylation of 2‐(methylthio)pyrimidin‐4(3H)‐ones with ethyl 2‐bromoethanoate followed by oxidation of the 2‐methylthio group, displacement of the obtained 2‐methylsulfonyl group with amines, hydrazinolysis of the obtained ethyl (2‐amino‐substituted pyrimidin‐4‐yloxy)acetates to give the corresponding hydrazides and their cyclization under the treatment with ethyl O‐ethyl xanthate or carbonyldiimidazole to 1,3,4‐oxadiazole‐2(3H)‐thiones and 1,3,4‐oxadiazol‐2(3H)‐one, correspondingly. In addition, two 1,3,4‐oxadiazole‐2(3H)‐thiones were converted into (N3)‐morpholinomethyl derivatives by the Mannich reaction with formaldehyde and morpholine. The yields of intermediates and target compounds ranged from moderate to excellent. The synthesized compounds were characterized by 1H and 13C NMR spectra and HRMS data, their purity was controlled by TLC. The synthesized pyrimidine‐based 1,3,4‐oxadiazoles (18 compounds) were tested as inhibitors of the HDAC4 and HDAC8 isoforms and their inhibitory activity was compared with that of Vorinostat. Most of the oxadiazolethiones containing methyl group at the position 6 of the pyrimidine moiety were found to be more selective towards HDAC8, while oxadiazolethiones with propyl group in the pyrimidine ring were active against HDAC4. Among the tested compounds, 5‐((2‐(dibutylamino)‐6‐propylpyrimidin‐4‐yloxy)methyl)‐1,3,4‐oxadiazole‐2(3H)‐thione (48) was found to have the strongest inhibitory activity for HDAC4 isoform (IC50 = 4.2 μM vs. IC50 = 59 μM for Vorinostat) while 5‐((2‐(cyclopentylamino)‐6‐propylpyrimidin‐4‐yloxy)methyl)‐1,3,4‐oxadiazole‐2(3H)‐thione (50) was the most potent HDAC8 inhibitor (IC50 = 6.8 μM). [ABSTRACT FROM AUTHOR]

An efficient chromoselective photochemical process is presented for the synthesis of 2H‐azirines and 1,3‐diazabicylo[3.1.0]hex‐3‐enes from readily available vinyl azides. The method exploits continuous flow photochemistry to enable the safe consumption of the hazardous azide group and provides uniform irradiation using high‐power LEDs at 365–450 nm. Additionally, a scaled telescoped process has been developed providing access to drug‐like 1,6‐dihydropyrimidines and pyrimidines via integrated ring‐expansion and oxidation reactions. Given the prevalence of various azacyclic targets in pharmaceutical, agrochemical and materials applications it is anticipated that this methodology will enable further exploitations of these important scaffolds. [ABSTRACT FROM AUTHOR]

As a vital biological molecule, H2O2(Hydrogen Peroxide) is involved in different physiological and pathological processes. And in addition to this, H2O2 is suitable for medical wound disinfection, environmental disinfection and food disinfection. Accordingly, it is of high significance to conveniently and effectively detect H2O2 in the environment and organisms. This subject synthesised a fluorescent probe Pyrimidine-Se by using selenomorpholine and pyrimidine dye, which detect H2O2 in an aqueous environment. Pyrimidine-Se has a large Stokes shift (Δλ = 155 nm), which can specifically and quickly quantitatively detect H2O2. When the probe Pyrimidine-Se reacted with H2O2, the Se(II) in the selenomorpholine was oxidised to Se(IV), so the electron withdrawing ability of the electron withdrawing group of Pyrimidine-Se was improved, and the fluorescence intensity of the probe were enhanced. Interestingly, Se(IV) can be reduced by GSH (Glutathione) to Se(II) to quench the fluorescence, and this redox cycle can continue several times, which indicated that it can have a potential of real-time monitoring the redox state in vivo. The probe was also satisfactorily used to detect H2O2 in Argentina Bloodfin larvaes and abnormal H2O2 content in some organs was detected. [ABSTRACT FROM AUTHOR]

Pyrimidine‐based derivatives have attracted a lot of interest in heterocyclic chemistry due to its versatile structure and diverse biological activities. This study provides a comprehensive overview of synthetic strategy of different pyrimidine ring and highlights their biological importance. In this article, we start off by going through the fundamental procedures for the synthesis of pyrimidine scaffolds, including both conventional and contemporary synthetic techniques. These works cover a range of therapeutic domains, such as effects that are anticancer, antibacterial, antiviral, anti‐inflammatory, antioxidant, antimalarial, and so on. Moreover, we have summarized with a discussion of future prospects and challenges in the field of pyrimidine heterocyclic chemistry. This thorough review is a significant resource for researchers in medicinal chemistry and related fields since it offers insightful information about the synthetic methods and biological applications of pyrimidine‐based derivatives. [ABSTRACT FROM AUTHOR]

Considering the unprecedented attributes governed by metal-organic framework nanostructures, the present report discloses the fabrication of [Zn2(H2N-BDC)2(4-bpdh)]·3DMF as a Zn-based MOF catalyst (TMU-16-NH2 (TMU = Tarbiat Modares University)) through the coordination of 2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene (4-bpdh) ligand to the Zn(NO3)2·6H2O salt under hydrothermal approach. In order to certify the successful synthesis of the catalyst, FT-IR, XRD, TGA, Elemental microanalysis, ICP OES and BET measurements were employed. The developed TMU-16-NH2 catalytic agent acts as a promising candidate to deliver a new class of pharmaceutically relevant 2,4-diphenylpyrido[4,3-d]pyrimidine scaffolds via the Michael addition annulations of benzimidamid hydrochloride to (3E,5E)-3,5-bis-(benzylidene)-4-piperidone reacting species. The devised methodology is accompanied with noteworthy benefits including mild reaction conditions, wide substrate scope, excellent product yields and short reaction span. Besides, facile retrievability and remarkable reusability of the catalyst for 5 successive runs without any appreciable loss in catalytic efficacy are the additional factors that rationalize this protocol as worthwhile. Our findings highlight the potential of using MOFs as efficient and versatile catalysts in organic synthesis and contribute to the growing body of literature on the synthesis of pyrido[4,3-d]pyrimidines with diverse biological activities. [ABSTRACT FROM AUTHOR]

An approach was developed for the synthesis of polyfunctionalized pyrimidines based on analogs of 1,2,4-triketones. Acetal-substituted β-diketones are involved in the condensation with amidines in the presence of an excess of (EtO)3B/Et3N in acetonitrile. The conditions of the acid hydrolysis of acetal-containing pyrimidines were found to depend on the nature of substituents in diazine. The use of 1,2,4-triketone in the condensation with amidine allows the synthesis of acetylpyrimidine in one step. [ABSTRACT FROM AUTHOR]

A new DES (MTPPBr-PHTH-DES) was prepared from a mixture of methyltriphenyl-phosphonium bromide (MTPPBr) and phthalic acid (PHTH). The eutectic point phase diagram showed that a one-to-one molar ratio of MTPPBr to PHTH is the optimal molar ratio for the synthesis of new DES. Then, it was characterized with various techniques such as FT-IR, TGA/DTA, densitometer, eutectic point, and NMR and used as a novel acid catalyst in the synthesis of pyrimido[4,5-d]pyrimidines and pyrano[3,2-c]chromes in solvent-free condition. Short reaction time, low temperature, high efficiency, green condition, and easy recycling and separation of the DES catalyst are among the most important features of the presented method. [ABSTRACT FROM AUTHOR]

Lung cancer (LC) ranks second most prevalent cancer in females after breast cancer and second in males after prostate cancer. Based on the GLOBOCAN 2020 report, India represented 5.9% of LC cases and 8.1% of deaths caused by the disease. Several clinical studies have shown that LC occurs because of biological and morphological abnormalities and the involvement of altered level of antioxidants, cytokines, and apoptotic markers. In the present study, we explored the antiproliferative activity of indeno[1,2-d]thiazolo[3,2-a]pyrimidine analogues against LC using in-vitro, in-silico, and in-vivo models. In-vitro screening against A549 cells revealed compounds 9B (8-methoxy-5-(3,4,5-trimethoxyphenyl)-5,6-dihydroindeno[1,2-d]thiazolo[3,2-a]pyrimidine) and 12B (5-(4-chlorophenyl)-5,6-dihydroindeno[1,2-d]thiazolo[3,2-a]pyrimidine) as potential pyrimidine analogues against LC. Compounds 9B and 12B were docked with different molecular targets IL-6, Cyt-C, Caspase9, and Caspase3 using AutoDock Vina 4.1 to evaluate the binding affinity. Subsequently, in-vivo studies were conducted in albino Wistar rats through ethyl-carbamate (EC)- induced LC. 9B and 12B imparted significant effects on physiological (weight variation), and biochemical (anti-oxidant [TBAR's, SOD, ProC, and GSH), lipid (TC, TG, LDL, VLDL, and HDL)], and cytokine (IL-2, IL-6, IL-10, and IL-1β) markers in EC-induced LC in albino Wistar rats. Morphological examination (SEM and H&E) and western blotting (IL-6, STAT3, Cyt-C, BAX, Bcl-2, Caspase3, and caspase9) showed that compounds 9B and 12B had antiproliferative effects. Accordingly, from the in-vitro, in-silico, and in-vivo experimental findings, we concluded that 9B and 12B have significant antiproliferative potential and are potential candidates for further evaluation to meet the requirements of investigation of new drug application. [ABSTRACT FROM AUTHOR]

1,3,4‐Oxadiazole and its derivatives are well known assorted motif in drug design and development. The development of bacterial infection drug resistance serves as justification for the discovery of novel antimicrobial drugs. Thus, a novel series of 1,3,4‐oxadiazole derivatives linked to pyrrolo[2,3‐d]pyrimidine 6 a–f and 7 a–e was designed, synthesized and fully characterized by 1H‐NMR, 13C‐NMR, FT‐IR and mass spectroscopic analysis. All of the compounds′ in‐vitro antibacterial and antifungal activities were reported, and final oxadiazoles 6 d, 6 e, 6 f, and 7 e showed excellent antimicrobial inhibitory activity as compared to standard drugs. The compounds 6 f and 7 a exhibited potent antifungal activity as a potent inhibitor against C. albicans with MICs 4.0±0.03, 7.5±0.02 μg/mL respectively. In order to determine the different binding interactions that the most active oxadiazoles had with the Staphylococcus aureus DHFR enzyme, a docking study was conducted. The results indicated that the residues of amino acid Thr96(X), Leu62(X), Arg44(X), Asn18(X), Glu17(X), Lys45(X), Thr121(X), Gln95(X), Asp120(X), Ser64(X), Gly94(X), and Phe16(X) had promising energy value, within the range of −6.84 to −9.63 kcal/mol (PDB: 3FRA). The most effective inhibitors, 6 and 7, also underwent in silico ADMET tests to predict their pharmacokinetic and physicochemical characteristics. [ABSTRACT FROM AUTHOR]

The nitro groups are introduced into 4-(1H-1,2,4-triazol-1-yl) pyrimidine to substitute the hydrogen atoms successively, through which a total of 31 derivatives are constructed to look for high energy density compounds (HEDCs). To probe the thermal stabilities, the heats of formation (HOFs) are calculated by using the G3MP2 method. To explore the dynamic stability, the natural bond orbital (NBO) analysis is performed to confirm the trigger bond, for which the bond dissociation energy is calculated using the B3PW91 method with the 6-311 + G(d,p) basis set. Furthermore, the detonation velocity (D), the detonation pressure (P), the molecular density (ρ), the explosive heat (Q), and character height (H50) are also predicted. Based on our calculation, it is confirmed that D1, D2, D5, and E are potential high-energy-density compounds with sufficient stability and excellent detonation performance. [ABSTRACT FROM AUTHOR]

A straightforward protocol has been developed to access 3-selenylated pyrazolo[1,5-a]pyrimidines from readily available amino pyrazoles, chalcones, and diaryl/dialkyl diselenides. This I2-catalyzed methodology is highly useful for synthesizing a wide range of functionalized 3-(aryl/alkylselanyl)pyrazolo[1,5-a]pyrimidine derivatives. Mechanistic investigation disclosed that iodine catalysis is very important in both the cyclization process as well as in the C-H selenylation step. Moreover, the developed reaction conditions are also applicable for the cyclization of amino pyrazole with enaminone followed by C-H selenylation in one pot. The use of simple reagents and catalyst, wide substrate scope, mild and metal-free reaction conditions, and practical applicability are the attractive facets of this approach. [ABSTRACT FROM AUTHOR]

The presence of one or more fluorine atoms in six-membered nitrogen heterocycles significantly impacts their chemical and physical properties, making them important in various applications, including pharmaceuticals and agrochemicals. This review, therefore, surveys the recent advances (mostly from 2010 onwards) in the synthesis of fluorinated six-membered N-heterocyclic compounds, including both the use of fluorinated starting materials and the introducing of fluorine atoms in the heterocyclic core and in either case exploring the benefits of microwave-assisted processes. [ABSTRACT FROM AUTHOR]

Unusual direction of the C–H arylation of 2-(het)aryl[1,2,4]triazolo[1,5-a]pyrimidines with (het)aryl halides under catalysis by ruthenium(II) complexes has been revealed. The reaction involved activation of the C7–H bond rather than the Cα–H bond of the (het)aryl substituent at C2 of the triazolopyrimidine core. The arylation of 2-substituted [1,2,4]triazolo[1,5-a]pyrimidines with (het)aryl bromides afforded a series of 7-(het)aryl derivatives in good yields. [ABSTRACT FROM AUTHOR]

Uracil-thymine dehydrogenase (UTDH), which catalyzes the irreversible oxidation of uracil to barbituric acid in oxidative pyrimidine metabolism, was purified from Rhodococcus erythropolis JCM 3132. The finding of unusual stabilizing conditions (pH 11, in the presence of NADP+ or NADPH) enabled the enzyme purification. The purified enzyme was a heteromer consisting of three different subunits. The enzyme catalyzed oxidation of uracil to barbituric acid with artificial electron acceptors such as methylene blue, phenazine methosulfate, benzoquinone, and α-naphthoquinone; however, NAD+, NADP+, flavin adenine dinucleotide, and flavin mononucleotide did not serve as electron acceptors. The enzyme acted not only on uracil and thymine but also on 5-halogen-substituted uracil and hydroxypyrimidine (pyrimidone), while dihydropyrimidine, which is an intermediate in reductive pyrimidine metabolism, and purine did not serve as substrates. The activity of UTDH was enhanced by cerium ions, and this activation was observed with all combinations of substrates and electron acceptors. • Uracil-thymine dehydrogenase was found to be a heteromer consisting of three different subunits. • Uracil-thymine dehydrogenase catalyzed oxidation of uracil with artificial electron acceptors. • The activity of uracil-thymine dehydrogenase was enhanced by cerium ions. [ABSTRACT FROM AUTHOR]

Over the years, human dihydroorotate dehydrogenase (hDHODH), which is a key player in the de novo pyrimidine‐biosynthesis pathway, has been targeted in the treatment of several conditions, including autoimmune disorders and acute myelogenous leukaemia, as well as in host‐targeted antiviral therapy. A molecular exploration of its inhibitor‐binding behaviours yielded promising candidates for innovative drug design. A detailed description of the enzymatic pharmacophore drove the decoration of well‐established inhibitory scaffolds, thus gaining further in vitro and in vivo efficacy. In the present work, using X‐ray crystallography, an atypical rearrangement was identified in the binding pose of a potent inhibitor characterized by a polar pyridine‐based moiety (compound 18). The crystal structure shows that upon binding compound 18 the dynamics of a protein loop involved in a gating mechanism at the cofactor‐binding site is modulated by the presence of three water molecules, thus fine‐tuning the polarity/hydrophobicity of the binding pocket. These solvent molecules are engaged in the formation of a hydrogen‐bond mesh in which one of them establishes a direct contact with the pyridine moiety of compound 18, thus paving the way for a reappraisal of the inhibition of hDHODH. Using an integrated approach, the thermodynamics of such a modulation is described by means of isothermal titration calorimetry coupled with molecular modelling. These structural insights will guide future drug design to obtain a finer Kd/logD7.4 balance and identify membrane‐permeable molecules with a drug‐like profile in terms of water solubility. [ABSTRACT FROM AUTHOR]

Dienamine 2 was synthesized by reacting 5‐aminopyrazole 1 with two moles of (DMF DMA). Enamine 2 underwent subsequent reactions with various reagents in different reaction media, leading to the formation of distinct compounds. In an acidic environment, enamine 2 reacted with acetyl acetone, benzoyl acetone, dimedone, and ethyl acetoacetate, resulting in the synthesis of compounds 9a, 9b, 13, and 17, respectively. Conversely, in a basic medium, dienamine 2 combined with malononitrile, ethyl cyanoacetate, and malononitrile dimer, yielding compounds 21a, 21b, and 25. Moreover, by reacting with ammonium acetate in acetic acid, dienamine 2 produced compounds 28. The synthesized compounds underwent in vitro testing against various bacterial and fungal strains, revealing significant antibacterial activity against hazardous bacterial strains. To identify potential bacterial targets, an in‐silico study was initiated. Molecular docking investigations indicated that compound 25 exhibited the highest binding affinity toward dihydrofolate reductase and penicillin‐binding proteins. Furthermore, compound 25 demonstrated robust physiochemical properties, bioavailability, and drug‐like characteristics. These results collectively suggest the potential of compound 25 as a promising antibacterial agent with favorable drug properties. [ABSTRACT FROM AUTHOR]

The possibility of generating a carbanion using the reaction of 3-bromo-5,7-dimethylpyrazolo[1,5-a]pyrimidine with BunLi followed by the electrophilic addition was investigated. The obtained results provide evidence for the presence of several reaction centers in the substrate, resulting in the formation of unexpected reaction products. These results offer new prospects for the functionalization of pyrazolo[1,5-a]pyrimidines and allow the preparation of new pharmacologically active derivatives of this series. The structures and purity of all the synthesized compounds were confirmed by 1H and 13C NMR spectroscopy, mass spectrometry, elemental analysis, and X-ray crystallography. [ABSTRACT FROM AUTHOR]

A series of thioureas 7a–k containing pyrimidine and a D -glucose moiety were synthesized through the reaction between substituted 2-aminopyrimidines 3a–k and tetra-O-acetyl-β- D -glucopyranosyl isothiocyanate 6. The yields achieved were 55–77%. Compounds 7a–k were screened for their anticancer activity against breast adenocarcinoma MCF-7, hepatocellular carcinoma HepG2, cervical cancer HeLa, and lung adenocarcinoma SK-LU-1 cell lines. The compounds that exhibited the highest potential inhibitory activity included 7b (IC50 = 1.16 ± 0.22 μM and 1.22 ± 0.41 μM against MCF-7 and SK-LU-1 cells, respectively), 7e (IC50 = 1.12 ± 0.13 μM against HeLa cells), and 7h (IC50 = 1.12 ± 0.11 μM against HepG2 cells). Compounds 7h and 7k exhibited EGFR inhibitory activity with IC50 values of 12.23 ± 0.21 nM and 24.16 ± 0.23 nM, respectively. They also exhibited VEGFR-2 inhibitory activity with IC50 values of 19.13 ± 1.12 nM and 25.62 ± 1.32 nM, respectively, in comparison with sorafenib. Induced-fit docking simulation for the most active inhibitor 7h was carried out on the enzyme 4HJO in order to elucidate its inhibitory potential. The obtained results showed that compound 7h was compatible with the active site of the EGFR tyrosine kinase domain of 4HJO with residues Lys692, Lys704, Met769, and Cys773. Molecular dynamics simulation in a water solvent system showed that the active interactions with these residues played an important role in stabilizing complex 7h/ 4HJO in the active pocket. [ABSTRACT FROM AUTHOR]

A novel series of dihydropyrimidine/sulphonamide hybrids 3a-j with antiinflammatory properties have been developed and tested as dual mPGES-1/5- LOX inhibitors. In vitro assay, results showed that compounds 3c, 3e, 3h, and 3j were the most effective dual inhibitors of mPGES-1 and 5-LOX activities. Compound 3j was the most potent dual inhibitor with IC50 values of 0.92 ^M and 1.98 ^M, respectively. In vivo, anti-inflammatory studies demonstrated that compounds 3c, 3e, 3h, and 3e had considerable anti-inflammatory activity, with EI% ranging from 29% to 71%. Compounds 3e and 3j were equivalent to celecoxib after the first hour but exhibited stronger anti-inflammatory effects than celecoxib after the third and fifth hours. Moreover, compounds 3e and 3j significantly reduced the levels of pro-inflammatory cytokines (PGE2, TNF-a, and IL-6) with gastrointestinal safety profiles. Molecular docking simulations explored the most potent derivatives' binding affinities and interaction patterns within mPGES-1 and 5-LOX active sites. This study disclosed that compound 3j is a promising anti-inflammatory lead with dual mPGES-1/5-LOX inhibition that deserves further preclinical investigation. [ABSTRACT FROM AUTHOR]

Background: Osteoporosis (OP), the "silent epidemic" of our century, poses a significant challenge to public health, predominantly affecting postmenopausal women and the elderly. It evolves from mild symptoms to pronounced severity, stabilizing eventually. Unique among OP's characteristics is the altered metabolic profile of affected cells, particularly in pyrimidine metabolism (PyM), a crucial pathway for nucleotide turnover and pyrimidine decomposition. While metabolic adaptation is acknowledged as a therapeutic target in various diseases, the specific role of PyM genes (PyMGs) in OP's molecular response remains to be clarified. Methods: In pursuit of elucidating and authenticating PyMGs relevant to OP, we embarked on a comprehensive bioinformatics exploration. This entailed the integration of Weighted Gene Co-expression Network Analysis (WGCNA) with a curated list of 37 candidate PyMGs, followed by the examination of their biological functions and pathways via Gene Set Variation Analysis (GSVA). The Least Absolute Shrinkage and Selection Operator (LASSO) technique was harnessed to identify crucial hub genes. We evaluated the diagnostic prowess of five PyMGs in OP detection and explored their correlation with OP's clinical traits, further validating their expression profiles through independent datasets (GSE2208, GSE7158, GSE56815, and GSE35956). Results: Our analytical rigor unveiled five PyMGs—IGKC, TMEM187, RPS11, IGLL3P, and GOLGA8N—with significant ties to OP. A deeper dive into their biological functions highlighted their roles in estrogen response modulation, cytosolic calcium ion concentration regulation, and GABAergic synaptic transmission. Remarkably, these PyMGs emerged as potent diagnostic biomarkers for OP, distinguishing affected individuals with substantial accuracy. Conclusions: This investigation brings to light five PyMGs intricately associated with OP, heralding new avenues for biomarker discovery and providing insights into its pathophysiological underpinnings. These findings not only deepen our comprehension of OP's complexity but also herald the advent of more refined diagnostic and therapeutic modalities. [ABSTRACT FROM AUTHOR]

No biomarker has yet been identified that allows accurate diagnosis and prognosis of oral cancers. In this study, we investigated the presence of key metabolites in oral cancer using proton nuclear magnetic resonance (NMR) spectroscopy to identify metabolic biomarkers of gingivobuccal oral squamous cell carcinoma (GB-OSCC). NMR spectroscopy revealed that uracil was expressed in 83.09% of tumor tissues and pyrimidine metabolism was active in GB-OSCC; these results correlated well with immunohistochemistry (IHC) and RNA sequencing data. Based on further gene and protein analyses, we proposed a pathway for the production of uracil in GB-OSCC tissues. Uridinetriphosphate (UTP) is hydrolyzed to uridine diphosphate (UDP) by CD39 in the tumor microenvironment (TME). We hypothesized that UDP enters the cell with the help of the UDP-specific P2Y6 receptor for further processing by ENTPD4/5 to produce uracil. As the ATP reserves diminish, the weakened immune cells in the TME utilize pyrimidine metabolism as fuel for antitumor activity, and the same mechanism is hijacked by the tumor cells to promote their survival. Correspondingly, the differential expression of ENTPD4 and ENTPD5 in immune and tumor cells, respectively, indicatedtheir involvement in disease progression. Furthermore, higher uracil levels were detected in patients with lymph node metastasis, indicating that metastatic potential is increased in the presence of uracil. The presence of uracil and/or expression patterns of intermediate molecules in purine and pyrimidine pathways, such asCD39, CD73, and P2Y6 receptors together with ENTPD4 and ENTPD5, hold promise as biomarker(s) for oral cancer diagnosis and prognosis. [ABSTRACT FROM AUTHOR]

A concise set of 4‐substituted pyrazolo[3,4‐d]pyrimidine carboriboside analogues was synthesized in a divergent fashion via a central intermediate. An oxaziridine reagent allowed the synthesis of a crucial hydrazine glycon intermediate, which was transformed through a base‐build‐up strategy into the desired intermediate using a commercially available pyrimidine building block. Reaction with a variety of nucleophiles allowed late‐stage diversification. All analogues were evaluated for activity against a representative panel of Trypanosomatida. A methoxy‐substituted analogue displayed single‐digit micromolar activity against two subspecies of Trypanosoma brucei in cellular assays. [ABSTRACT FROM AUTHOR]

2-Chloro-5-[(6-hydroxy-4,7-dimethoxy-1-benzofuran-5-yl)carbonyl]pyridine-3-carbonitrile (3) was synthesized and its chemical reactivity was investigated toward a diversity of binucleophiles. Treatment of compound 3 hydrazine hydrate and phenylhydrazine produced pyrazolo[3,4-b]pyridines while isoxazolo[5,4-b]pyridine was obtained from reacting compound 3 with hydroxylamine. A diversity of pyrido[2,3-d]pyrimidines was synthesized from treatment of staring substrate 3 with some 1,3-N,N-binucleophiles. Treating compound 3 with some 1,4-binucleophiles including ethylenediamine, o-phenylenediamine, 2-aminophenol and 2-aminothiophenol furnished pyrido[2,3-e][1,4]diazepine 12 and pyrido[2,3-b][1,5] benzodiazepine 13, pyrido[2,3-b][1,5]benzoxazepine 14 and pyrido[2,3-b][1,5] benzothiazepine 15, respectively. The synthesize compounds shown remarkable effect against yeast and fungus, while compounds 4 and 7–11 exhibit excellent efficacy against all types of Gram + and Gram - bacteria. Structures of the produced compounds were established using analytical and spectroscopic tools. [ABSTRACT FROM AUTHOR]

Azido-modified nucleosides have been extensively explored as substrates for click chemistry and the metabolic labeling of DNA and RNA. These compounds are also of interest as precursors for further synthetic elaboration and as therapeutic agents. This review discusses the chemistry of azidonucleosides related to the generation of nitrogen-centered radicals (NCRs) from the azido groups that are selectively inserted into the nucleoside frame along with the subsequent chemistry and biological implications of NCRs. For instance, the critical role of the sulfinylimine radical generated during inhibition of ribonucleotide reductases by 2′-azido-2′-deoxy pyrimidine nucleotides as well as the NCRs generated from azidonucleosides by radiation-produced (prehydrated and aqueous) electrons are discussed. Regio and stereoselectivity of incorporation of an azido group ("radical arm") into the frame of nucleoside and selective generation of NCRs under reductive conditions, which often produce the same radical species that are observed upon ionization events due to radiation and/or other oxidative conditions that are emphasized. NCRs generated from nucleoside-modified precursors other than azidonucleosides are also discussed but only with the direct relation to the same/similar NCRs derived from azidonucleosides. [ABSTRACT FROM AUTHOR]