Heterocyclic Research Articles

Exploring the Anticancer Potential of Triazine Derivatives: An Outlook of Designing Strategies, Docking Studies, and Structure‐Activity Relationships (SAR)

AbstractCancer is a disease characterized by uncontrolled cell growth resulting from genetic and epigenetic changes accumulating within a cancer cell population. Despite the milestone discovery of chemotherapeutic drugs against cancer, cancer remains tough to cure. Therefore, cancer has the second‐highest global death rate. There are certain factors such as genetic mutation, cancer cell diversity, metastasis, and resistance, which limit chemotherapy. To combat cancer, it's crucial to find novel therapeutic tactics and produce novel drugs that target cancer cells without affecting healthy cells. Heterocyclic compounds influence certain molecular targets to find novel lead structures can be a noteworthy strategy for the development of potential anticancer agents. Triazine, a low‐cost and widely available heterocyclic scaffold, has piqued researchers’ interest in developing innovative designing strategies. This review presents the advancement of three different isomers of triazines as anticancer agents. The main focus of this review is to provide the advancement of designing strategies, structure‐activity relationships, and docking studies of triazine derivatives as anticancer agents the available triazine‐containing drugs, and the status of clinical trials of triazine‐containing drugs were also highlighted. Lastly, we have also concluded the most potent derivatives and their hybridization with another ring to justify the particular anticancer activity.

Investigation of Apoptotic and Anticancer Effects of 2-substituted Benzothiazoles in Breast Cancer Cell Lines: EGFR Modulation and Mechanistic Insights.

Benzothiazole derivatives, a class of heterocyclic compounds, exhibited diverse biological activities influenced by substituents in the thiazole ring. This study aimed to synthesize these compounds with two functional groups to investigate their potential as anticancer agents, particularly against breast cancer. While previous research demonstrated the efficacy of 2-substituted benzothiazoles against glioma and cervical and pancreatic cancer cells, there is a gap in studies targeting breast cancer. The synthesized compounds were tested in vitro using MCF-7, MDA-MB-231, and MCF-10A cell lines, with Doxorubicin as the positive control. Various assays were conducted, including Annexin V/PI, cell cycle analysis, wound healing, and measurement of mitochondrial membrane potential. Protein expression of EGFR and transcription levels of apoptosis-related genes (Bax and Bcl-xL) and cancer progression-related genes (JAK, STAT3, ERK, AKT, mTOR) were analyzed. Additionally, the balance between antioxidants and oxidants was evaluated by measuring TAS and TOS levels. Our findings revealed that benzothiazole compounds significantly inhibited breast cancer cell growth by reducing cell motility, disrupting mitochondrial membrane potential, and inducing cell cycle arrest in the sub-G1 phase. These compounds increased reactive oxygen species accumulation, leading to cell death. Furthermore, they decreased EGFR protein levels, increased Bax gene transcription, and downregulated the expression of genes such as JAK, STAT3, ERK, AKT, and mTOR. In conclusion, benzothiazole derivatives exhibited potent inhibitory effects on breast cancer in vitro by promoting apoptosis, downregulating EGFR activity, and modulating key signaling pathways, including JAK/STAT, ERK/MAPK, and PI3K/Akt/mTOR. These results highlighted the potential of benzothiazole derivatives as novel therapeutic agents for breast cancer treatment.

Synthesis, Crystal Structure, Intermolecular Interactions, HOMO-LUMO, MEP, NLO Properties, and DFT/TD-DFT Investigation of (Z)-5-(4-Nitrobenzylidene)-3-N(3-Chlorophenyl)-2-Thioxothiazolidin-4-One

A novel heterocyclic compound named (Z)-5-(4-nitrobenzylidene)-3-N(3-chlorophenyl)-2-thioxothiazolidin-4-one (NCTh) was synthesized and analyzed using various techniques, including single crystal X-ray diffraction, FT-IR, UV-Vis, NMR spectroscopy, and mass spectral data methods. NCTh was observed to crystallize in the triclinic crystal system P-1 space group. To validate the experimental findings, density functional theory (DFT) calculations were performed using the B3LYP functional with the 6-311 G(d,p) basis set. The results indicated good agreement in geometrical parameters between the experimental and theoretical outcomes. The study also calculated HOMO-LUMO energies, molecular electrostatic potential (MEP), and global chemical reactivity descriptors to evaluate the compound’s reactivity. Additionally, the study conducted reduced density gradient and Hirshfeld surface analyses to reveal attractive, repulsive, and van der Waals strong and weak interactions. The calculation of thermodynamic parameters was also included. The study focused on investigating the nonlinear optical (NLO) properties of NCTh, which were characterized through key parameters such as the electric dipole moment (µ), polarizability (α), first-order hyperpolarizability (β), and second-order hyperpolarizability (γ). These properties provide insights into the material’s potential applications in optical and photonic technologies. Additionally, a molecular docking study was performed to further explore the structure-activity relationship, particularly in a biological context. The docking results revealed a strong ligand-protein interaction, with a binding energy of −10.3 kcal/mol, indicating significant affinity. Moreover, the inhibition constant (Ki) was calculated to be 0.0281 μM, suggesting a highly potent interaction, which could be relevant for drug design or biochemical applications.

Heterogeneous Catalysis in the Synthesis of Nitrogen‐Containing Heterocyclics

AbstractThe synthesis of nitrogen‐containing heterocyclic compounds using heterogeneous catalysis is a topic of significant interest in organic synthesis and chemical research. Heterogeneous catalysis offers several advantages over homogeneous catalysis, including easier separation and recovery of the catalyst, reduced waste generation, and potentially higher stability and reusability. In this review, the pivotal role of heterogeneous catalysis in synthesizing nitrogen‐containing heterocyclic compounds is explored. Various types of heterocycles and the specific applications of these compounds in drug discovery and material development are discussed in detail. This review discusses various examples of heterogeneous catalysts employed in the synthesis of nitrogen‐containing heterocycles, including metal oxides, supported metals, metal nanoparticles, zeolites, and other porous materials. Emphasis is placed on the mechanistic insights and reaction pathways facilitated by different catalysts. Additionally, recent advancements and innovations in the field are discussed, including novel catalyst designs, green chemistry approaches, and emerging trends in catalytic materials. The aim is to provide a comprehensive overview of the impact and potential of heterogeneous catalysis in this important area of organic synthesis.

A Comparative In Vitro Anticancer Evaluation and In Silico Study of New 1‐(1,3‐Oxazol‐5‐yl)piperidine‐4‐sulfonylamides

AbstractIn this work, we synthesized a series of new 1,3‐oxazole derivatives comprising the sulfonylamide group and tested their activity against the human tumor cell line panel. This study further explores the stereoelectronic characteristics of 1,3‐oxazol‐5‐sulfonylamides and new 1‐(1,3‐oxazol‐5‐yl)piperidine‐4‐sulfonylamides to connect their anticancer activity to the molecular structure. Combining in vitro and in silico methods, we analyzed how the proximity of the sulfonylamide group to the heterocyclic ring affects the structure–activity interplay. Herein, our assessment is based on the purported complexation of 1,3‐oxazoles with targeted biomolecular fragments involving the π‐stacking interaction and hydrogen bonding within the prospective complexes. Defining the probability of the prospective drug–target interactions, we detail conformational properties, donor/acceptor capabilities, electronic characteristics, and thermodynamic preference of produced sulfanylamide group containing 1,3‐oxazoles toward biomolecular fragments, identifying the nature of variations in anticancer activity.

Condensed Heterocyclic Compounds Based on 1,10-Phenatroline in the Electrocatalytic Production of Molecular Hydrogen: Effect of Substituents on the Efficiency of the Process

Condensed Heterocyclic Compounds Based on 1,10-Phenatroline in the Electrocatalytic Production of Molecular Hydrogen: Effect of Substituents on the Efficiency of the Process

Genetic and metabolic engineering approaches for enhanced biodesulfurization of petroleum fractions.

Sulfur, an abundant component of crude oil, causes severe damage to the environment, poses risks to human health, and poisons the catalysts used in combustion engines. Hydrodesulfurization, the conventionally used method, is not sufficient to remove thiophenes like dibenzothiophene (DBT) and other aromatic heterocyclic compounds. The push for "ultra-clean" fuels, with sulfur content less than 15 ppm, drives the need for deep desulfurization. Thus, in conjunction with hydrodesulfurization, efficient and eco-friendly methods of deep desulfurization, like biodesulfurization, are desirable. In biodesulfurization, naturally desulfurizing microorganisms are used, with genetic engineering and biotechnology, to reduce the sulfur content of crude oil to below 15 ppm. In this review, we describe genetic and metabolic engineering approaches reported to date to develop more efficient methods to carry out biodesulfurization, making it a practically applicable reality.

The applications of nanocatalysts in the synthesis of heterocyclic compounds

Nanocatalysts in heterocyclic synthesis are a very important direction in producing eco-friendly compounds. These catalysts can be reused up to six times without losing their quantity and efficiency. Most of these nanocatalysts are cheap, available, economical and safe for the environment. In this review, I focused on the synthesis of furans, pyrans, chromenes and thiazoles from nanocatalysts. For example, pyranopyrazoles 8a-c were synthesized by the multicomponent reactions between aldehydes 4a-c, malononitrile (5), ethyl acetoacetate (6) and hydrazine hydrate (7) using titanium dioxide as a nanocatalyst. KEY WORDS: Heterocyclic, Chromenes, Nanocatalysts, Eco-friendly compounds Bull. Chem. Soc. Ethiop. 2025, 39(1), 123-129. DOI: https://dx.doi.org/10.4314/bcse.v39i1.10

INCLUSION OF AZULENE STRUCTURAL UNITS IN THE BASIS OF CONJUGATED POLYMERS: IMPROVEMENT OF PROTON SENSITIVITY AND FLUORESCENCE

The growing interest in aromatic polymer compounds with an extended π-electron coupling system is explained by their importance as functional materials for organic optoelectronics. At present, much attention is paid to arylated, as well as substituted by electron acceptor and/or electron donor groups, aromatic and heteroaromatic compounds. One of the advantages of such conjugated aromatic systems is that they can fine-tune the electronic structure of materials in order to optimize their performance and morphology. In this regard, the structural isomer of naphthalene - azulene is of considerable interest. The nonalternant aromatic hydrocarbon azulene has unique electronic and spectral properties, including a polarized structure with a dipole moment of the order of 1,08 D and abnormal Anti-Kasha fluorescence S2→S0. The article discusses the synthesis of two fluorene-azulene π-conjugated copolymers using the modern methodology of organic synthesis as the Suzuki − Miyaura -cross−coupling reaction. It was shown that the interaction of 1,3-dibromazulene, as well as 2,7-Bis(3-bromoazulen-1-yl)-9,9-dioctyl-fluorene with 2,2'-(9,9-dioctyl-9H-fluorene-2,7-diyl)bis(1,3,2-dioxaborinane) under Suzuki − Miyaura cross-coupling conditions, azulene conjugate copolymers were synthesized: poly[2,7-(9,9-dioctylfluorenyl)-alt-(1ꞌ,3ꞌ - azulenyl)] and poly[1,3-bis(9ꞌ,9ꞌ-dioctylfluoren-2ꞌ-yl)azulenyl]-alt-[1ꞌꞌ,3ꞌꞌ - azulenyl]. It is revealed that neutral solutions of the obtained copolymers are nonfluorescent, but they become luminescent upon addition of trifluoroacetic acid. The «launching» of fluorescence occurs as a result of the formation of a 6 π-electron azulenyl cation, which rearranges the general electronic character of polymers, in particular, HOMO-LUMO levels and band gap. The obtained results demonstrate that the introduction of azulene units into a conjugated polymer framework has great potential for application as new protic functional materials.

Quantum chemical calculations and molecular docking studies of 5-amino-3-(2,5-dimethoxyphenyl)-1-isonicotinoyl-2,3-dihydro-1H-pyrazole-4-carbonitrile

Abstract The five-membered heterocycle pyrazole has two nitrogen atoms next to each other. Natural items and pharmaceuticals using pyrazole as the nucleus have demonstrated a wide range of biological activity. Medications with pyrazole cores may have better pharmacokinetics and pharmacological effects than medicines with similar heterocyclic rings. This is because the pyrazole core has unique physicochemical properties. In this study, 5-amino-3-(2,5-dimethoxyphenyl)-1-isonicotinoyl-2,3-dihydro-1H-pyrazole-4-carbonitrile is synthesized and characterized by means of spectrum and quantum chemical techniques. Using UV–vis absorption technique, Fourier transform infrared (FT-IR), and Fourier transform Raman (FT-Raman) techniques, the spectroscopic properties were examined. There were two regions visible in the experimental Raman as well as infrared spectra: 4,000–400 cm−1 along with 4,000–100 cm−1. The ideal molecular shape, vibrational frequencies, infrared intensity levels, and scattering from Raman were all assessed using density functional theory. The 13C (carbon) and 1H (proton) chemical shifts of the molecule were determined using nuclear magnetic resonance (NMR). The TD-DFT scheme was utilized to figure out speculative ultraviolet values and compare them to oscillator strength, electron excitation energies, and spectrum data from experiments. It is evident from the predicted HOMO-LUMO band separation energies that the transmission of charge takes place within a molecule’s structure. The chemical reactivity of the molecule has been calculated along with other global descriptive properties. Scientists investigated how charges move and the density of electrons inside a molecule using NBO analysis of the chemical they were studying. After examining the molecular electrostatic potential (MEP), a 3D picture was created that shows the compound’s nucleophilic and electrophilic areas. In addition to meeting all pertinent pharmacokinetic requirements, 5-amino-3-(2,5-dimethoxyphenyl)-1-isonicotinoyl-2,3-dihydro-1H-pyrazole-4-carbonitrile is also readily absorbed by the gastrointestinal system. Additionally, the chemical that was synthesized had a positive interaction with the target proteins of treatments for viruses, asthma, and heart failure, as shown by molecular docking.

Investigation of the Mechanism of Oxidative Potential Increase in Atmospheric Particulate Matter during Photoaging: Important Role of Aromatic Nitrogenous Compounds.

Particulate matter (PM) undergoing various aging processes in the atmosphere changes its toxicity. However, the mechanism of toxicity evolution is not fully clarified currently. This study demonstrates that photoaging promotes an increase in the oxidative potential (OP) of atmospheric PM by about 30%, and the increased OP is mainly attributed to the production of secondary organic compounds, while water-soluble metal ions contribute only 11%. The OP of nonextractable matters (NEMs) of atmospheric PM was mostly increased after photoaging, followed by water-soluble matters (WSMs). NEM can produce quinone-like functional groups and secondary persistent free radicals during photoaging, which are most likely to produce reactive oxygen species (ROS). For WSM, the conversion of low-oxidation humic-like substances (HULIS) to high-oxidation HULIS is the main reason for the increase in OP. Quinones, nitrophenols, and N-containing heterocycles are the OP contributors produced during the conversion process. Among them, quinones are the main secondary oxidizing active compounds, while nitro-phenolic compounds and N-containing heterocyclic compounds may play a catalyst-like role, facilitating the production of oxidizing active compounds and ROS in the newly converted high-oxidation HULIS. This study clarifies the secondary OP generation mechanism and provides new insights into the uncertainty of PM toxicity during atmospheric aging.

DABCO‐Saccharin Acetate as a Novel, Recyclable and Metal‐Free Catalyst for Eco‐Friendly Synthesis of Various Pyridazino[1,2‐a]indazole and 1H‐indazolo[1,2‐b]phthalazine Heterocycles Under Solvent‐Free Conditions

AbstractIn this research various pyridazino[1,2‐a]indazole and 1H‐indazolo[1,2‐b]phthalazine and 1H‐indazolo[1,2‐b]phthalazine derivatives were produced with a high yield via a multi‐component reaction of dimedone, aldehyde, hydrazine and anhydride compounds in the presence of a novel DABCO‐Saccharin acetate ([DABCOH][Sac‐CH3CO2]) ionic liquid under microwave irradiation. The applied method for producing these heterocyclic compounds demonstrated a number of desirable traits, including quick reactions, high yields of the final product, and straightforward separation of the product and catalyst from the reaction mixture.

Synthesis, Characterization, and Antimicrobial Evaluation of Thiadiazole Derivatives Derived from 2-Amino-5-Thio-1,3,4-Thiadiazole

This manuscript introduces a series of novel Schiff base and heterocyc-licring compounds, focusing on derivatives of 1,3-oxazepine and thiazo-lidinone.The derivative (2-Hydroxy-N-(5-mercapto-[1,3,4] thiadiazol-2-yl)-2-phenyl-acetamide was created by reacting ethyl mandelate ester[M1] and 2-amino-5-thio-1,3,4-thiadiazole compound to produce new compound [M2] and after that, compound [M2] was reacted with hydrazine hydrate 99% in dry DMF solvent, yielding the compound (N-(5-Hydrazino-[1,3,4]thiadiazol-2-yl)-2-hydroxy-2-phenyl-acetamide [M3]. In contrast , the Schiff base compound [M4] were synthesized by reacting compound [M3] with aromatic heterocyclic aldehyde (furan-2-carbaldehyde) in the presence of glacial acetic acid as a catalyst, and then Schiff base [M4] was reacted with maleic anhydride in dry benzene as a solvent to produce (1,3-Oxazepine) derivative [M5]. Additionally, the thiazolidinone derivative [M6] was synthesized through the reaction of equimolar amounts of (N-[5-(N'-Furan-2-yl-methylene-hydrazino)-[1,3,4]thiadiazol-2-yl]-2-hydroxy-2-phenyl-acetamide [M4] with thioacetic acid compound in chloroform as a solvent. The structural formula of all derivatives was confirmed by FT-IR and (1HNMR, 13CNMR) spectroscopy. The synthesized derivatives [M1-M6] were screened for their evaluated for antibacterial activity against S. aureus, S. epidermidis, E. coli, Klebsiella sp., and the fungus Candida albicans. Dimethyl sulfoxide (DMSO) was used as the solvent. Also, the ampicillin compound was used as the standard drug for comparison.

Visible-light-promoted [3 + 2] cycloaddition for the synthesis of spirooxindoles under external photocatalyst-free conditions

A visible-light-promoted [3 + 2] cycloaddition of 3-alkenylindole-2-ones with 2-mercaptoimidazoles for the construction of diverse imidazo[2,1-b]thiazole fused 3,3′-spirooxindoles has been developed. Mechanism studies have shown that this transformation is initiated through visible-light excitation of 3-alkenylindole-2-ones, rather than an electron donor-acceptor (EDA) complexes-promoted process. In summary, we have successfully developed a method for simultaneously constructing C−N and C−S bonds under visible-light conditions, and synthesized over 40 examples of new nitrogen- and sulfur-containing fused heterocyclic compounds with potential biological activity with a yield of up to 99 %. This method exhibits simple operation, mild reaction conditions, high atom economy, good functional group tolerance and does not require the use of any transition metals and external photocatalysts. Gram-scale reaction further demonstrates the practicality of this protocol.

New acetophenone scaffolds: Synthesis, antifungal activities, biocompatibility, molecular docking, ADMET analysis and dynamic simulations

In this work, the chemical reactivity of 2-cyano-N′-(1-phenylethylidene)acetohydrazide (3) towards different aldehydes is utilized to synthesize binary and fused heterocyclic compounds, including arylidenes 6, 7, 12, 13, 14, 18a-c, 19a,b, 20, chromone 23, and chromene derivatives 24, 26a-c, 29, and 30. The capability of newly synthesized compounds to inhibit fungal growth of Aspergillus niger ATCC 16404, A. flavus ATCC 9643, Penicillium chrysogenum ATCC 10106, and Rhizopus oryazae ATCC 96382 are assessed. It is observed that compound 29 had strong antifungal activity against all fungi with MFIC values varying from 250 to 1000 µg/ml, while compound 18a demonstrated potent antifungal effect against A. niger and A. flavus. In addition, it is found that compound 29 was cytotoxic to Vero cells at doses of 1000–500 µg/ml; however, no discernible variation was observed between the concentrations of 250–31.25 µg/ml. Moreover, the interactions between the promising compounds 18a, 19b, and 29 and antifungal target proteins are assessed using molecular docking. The results of the docking simulations demonstrated that these compounds demonstrated optimal binding energies and effectively engaged with the active sites of FDC1 protein in A. niger, UDP-N-acetylglucosamine in A. fumigatus, Adenosine 5′-phosphosulfate kinase in P. chrysogenum, and protease in Rhizopus oryazae. These interactions involved various types of molecular interactions, indicating that these compounds have the ability to impede enzymes and exhibit strong antimicrobial effects. Furthermore, the in-silico ADMET profiles of compounds 18a, 19b, and 29 reveal that they adhere to the Lipinski rules, suggesting favorable physicochemical properties. Also, MD simulations revealed stable complexes of 29 with anti-fungal receptors including fdc1, UDP-N-acetylglucosamine, APS kinase, and protease with RMSD (0.1–0.8, 0.19–0.25, 0.20–0.30, and 0.20–0.35 nm), RMSF (0.1–0.8 nm), SASA (140–155, 130–140, 135–145, and 120–130 nm2), and Rg (1.90–2.00, 1.80–1.90, 2.40–2.50, and 2.10–2.20 nm) respectively. Our results provide potential and promising compounds for fungal infection diseases.

Pharmacological investigations of newly synthesized oxazolones and imidazolones as COX-2 inhibitors

Oxazoles and Imidazoles are heterocyclic compounds with significant biological activities. The present study explores the pharmacological effects of some new oxazole and imidazole derivatives as potential COX-2 inhibitors. Docking studies of the compounds against targeted proteins COX-2 and TACE manifested good binding affinities for both the targets supporting their anti-inflammatory potential. Compounds (3F-A, 3F-B, N-A, N-B) were evaluated for in vivo anti-inflammatory effects by carrageenan-induced paw edema. Among all, compound N-A was found to be the most effective as it displayed most pronounced reduction in inflammation that was comparable to indomethacin. The in vivo tissue antioxidant activity was performed for estimation of the level of catalase, GSH, GST, and thiobarbituric acid in paw tissue. The results exhibited that targeted compounds improved the oxidative stress and restored the expression of enzymes. H &E staining revealed that aforesaid compounds displayed well-defined restoration of cellular damage. Compound NA exhibited maximum structural and functional preservation. Reduction in the expression of inflammatory markers was also analyzed by ELISA and maximum reduction in protein expression (COX-2 and TNF-a) was observed for compound N-B. Quantification of mRNA was done using PCR and a decrease in the expression of COX-2 mRNA level in treatment groups was depicted by all the new compounds but N-B showed maximum reduction in enzyme expression. All the results obtained from the present study have shown the significant anti-inflammatory potential of new compounds via the COX-2 inhibition pathway.

Isatin Bis-Imidathiazole Hybrids Identified as FtsZ Inhibitors with On-Target Activity Against Staphylococcus aureus.

In the present study, a series of isatin bis-imidathiazole hybrids was designed and synthesized to develop a new class of heterocyclic compounds with improved antimicrobial activity against pathogens responsible for hospital- and community-acquired infections. A remarkable inhibitory activity against Staphylococcus aureus was demonstrated for a subset of compounds (range: 13.8-90.1 µM) in the absence of toxicity towards epithelial cells and human red blood cells. The best performing derivative was further investigated to measure its anti-biofilm potential and its effectiveness against methicillin-resistant Staphylococcus aureus strains. A structure-activity relationship study of the synthesized molecules led to the recognition of some important structural requirements for the observed antibacterial activity. Molecular docking followed by molecular dynamics (MD) simulations identified the binding site of the active compound FtsZ, a key protein in bacterial cell division, and the mechanism of action, i.e., the inhibition of its polymerization. The overall results may pave the way for a further rational development of isatin hybrids as FtsZ inhibitors, with a broader spectrum of activity against human pathogens and higher potency.

The Effect of Reduced Nitrogen Fertilizer Application on japonica Rice Based on Volatile Metabolomics Analysis.

Nitrogen is critical for rice yield and quality, but its overuse can be detrimental to efficiency and the environment. To identify changes in the quality of rice in response to the reduced application of nitrogen fertilizer, we carried out a comprehensive metabolomics study of SuiJing 18 using volatile metabolomics methods. Our results showed that SuiJing 18 had a total of 358 volatile metabolites, mainly lipids (16.25%), terpenoids (15.41%), heterocyclic compounds (15.13%), and hydrocarbons (13.45%). SuiJing 18 underwent significant changes in response to the reduced application of nitrogen fertilizer. Key sweet volatile compounds such as 4-methyl-benzeneacetaldehyde, hexyl acetate, and 2-methylnaphthalene were present at significantly higher levels when nitrogen fertilizer was applied at a rate of 68 kg of pure nitrogen per hectare, and their flavor characteristics also differed significantly from the compounds resulting from the other two treatments. Focusing on 16 differential volatile metabolites, we further investigated their effects on flavor and quality, thus laying the foundation for a greater understanding of the biomarkers associated with changes in rice quality. This study contributes to a better understanding of the mechanisms underlying changes in rice quality after reduced nitrogen fertilizer application.

Heteroaryl Group Containing Trisubstituted Alkenes: Synthesis and Anti-Tumor Activity.

Pancreatobililary cancers are fatal solid tumors that pose a significant threat to human life. It is imperative to investigate novel small molecule active compounds for controlling these cancers. Heterocyclic compounds (e. g. gemcitabine) and multi-substituted alkenes (e. g. resveratrol) are commonly applied in tumor treatment. Researchers have proposed that the synthesis of new trisubstituted alkenes containing heteroaromatic rings by combining these two scaffolds may be a fresh strategy to develop new active molecules. In this study, we utilized alkenyl bromide and heteroaryl boronic acid as substrates, employing Suzuki coupling to generate a series of triarylethylenes featuring nitrogen, oxygen, and sulfur atoms. Through in vitro experiments, the results indicated that some compounds exhibited remarkable anti-tumor efficacy (e. g. IC50[3be, GBC-SD]=0.13 μM and IC50[3be, PANC-1]=0.27 μM). The results further demonstrated that the antitumor efficacy of these compounds was dependent on the heteroatom, π-system, skeleton-bonding site, and substituent type.

Bifunctional Nitrogen-Rich Heterocyclic Compounds: Synthesis, Photoluminescence and Energetic Properties.

Nitrogen-rich heterocyclic frameworks have attracted enormous interest in organic chemistry and materials science. However, their potential for developing photoluminescent materials remains underexplored due to their relatively low molecular stabilities. In this work, two tricyclic fused nitrogen-rich fluorescent heterocycles were synthesized and characterized. The photophysical properties of the synthesized 4 and 5 were investigated through theoretical and experimental studies. In addition, their physicochemical and energetic properties and the performance as an additive to the perovskite absorption layer of the perovskite solar cell were also studied.