UV-light intervened synthesis of imidazo fused quinazoline and its solvatochromism, antioxidant, antifungal and luminescence properties

Benzo[4,5]imidazole[2,1-b]quinazoline-1(2H)-one: An efficient fluorescent probe for the selective and sensitive detection of Cu(II) ions

Copper (Cu) is essential for biological systems and animal-plant tissues, but Cu2+ ions are also significant environmental pollutants. An imbalance in non-toxic Cu2+ levels can lead to health issues. This study focuses on the development of a novel fluorescent turn-on probe, 3,4-dihydrobenzo[4,5]imidazole[2,1-b]quinazoline-1(2H)-one (HBQ) for the selective and sensitive detection of Cu2+ ions. The synthesis of HBQ was achieved from the reaction of 2-((dimethylamino)methylene)-cyclohexane-1,3-dione and 2-aminobenzimidazole. The photophysical properties of HBQ were investigated in various solvents. The strong binding of HBQ to Cu2+ causes a blue shift in the emission maxima and enhanced fluorescence due to reduced non-radiative decay, highlighting its selectivity for Cu2+ detection. Absorption and emission spectroscopy revealed the binding interactions, sensitivity, and selectivity of HBQ toward Cu2+ ions. The turn-on fluorescence of HBQ shows high sensitivity, with detection (LOD) and quantification (LOQ) limits extending to sub-micron concentrations. The sensor's reliability and applicability were further validated using real samples, with a recovery rate of approximately 100 ± 2 %.

Quinazolinone-grafted polymers as novel insecticides: Synthesis, activity against Spodoptera littoralis, and environmental safety assessment

Insecticides are crucial for crop protection against pests; research aims to develop effective and safe insecticides. This study aimed to evaluate 11 quinazolinone-based derivatives grafted with chitosan, polymethylmethacrylate, and carboxymethylcellulose against larvae of the cotton leafworm Spodoptera littoralis. The synthesized 2-hydrazinyl-3-phenylquinazolin-4(3H)-one (compound 2) and its grafted polymers were characterized via 1H NMR, XRD, FT-IR, and TGA analyses. Under laboratory conditions, compound 2 exhibited significantly higher toxicity (LC50 = 153 μg/ml) than other grafted polymers (LC50 range 217-513 μg/ml) against third-instar larvae of S. littoralis. Compared with the control, compound 2 had substantial effects on pest population dynamics at a low-lethal concentration (LC10), such as reducing adult emergence to 76.8 % and egg hatchability to 32 %. The compound showed a favorable environmental profile with a moderate half-life of 51.5 days and exhibited acceptable safety for humans (IC50 = 56 μg/ml in MRC-5 cells). These characteristics suggest its potential for integration into sustainable pest management strategies, balancing effective pest control with environmental considerations. Further investigation of this insecticide candidate under different ecological settings is recommended to assess its field applicability and ecosystem impacts.

Quinazolines annelated at the N(3)-C(4) bond: Synthesis and biological activity

This review covers article and patent data obtained mostly within the period 2013-2023 on the synthesis and biological activity of quinazolines [c]-annelated by five- and six-membered heterocycles. Pyrazolo-, benzimidazo-, triazolo- and pyrimido- [c]quinazoline systems have shown multiple potential activities against numerous targets. We highlight that most research efforts are directed to design of anticancer and antibacterial agents of azolo[c]quinazoline nature. This review emphases both on the medicinal chemistry aspects of pyrrolo[c]-, azolo[c]- and azino[c]quinazolines and comprehensive synthetic strategies of quinazolines annelated at N(3)-C(4) bond in the perspective of drug development and discovery.

Research and development of N,N'-diarylureas as anti-tumor agents

Tumor neovascularization provides abundant nutrients for the occurrence and development of tumors, and is also an important factor in tumor invasion and metastasis, which has attracted extensive attention in anti-tumor therapy. Sorafenib is a clinically approved multi-targeted anti-tumor drug that targets vascular endothelial growth factor receptor (VEGFR) and inhibits the formation of tumor angiogenesis, thereby achieving the purpose of suppressing tumor growth. Since the approval of sorafenib, N,N'-diarylureas have received extensive attention as the key pharmacophore in its chemical structure. And a series of N,N'-diarylureas were designed and synthesized to screen a new generation of anti-tumor drug candidates through chemical modification and structural optimization. Moreover, the rational design of targeted drugs is beneficial to reduce toxic side effects and drug resistance and improve the curative effect. Here, this article reviews the research progress in the design, classification, structure-activity relationship (SAR) and biological activity of N,N'-diarylureas, in order to provide some prospective routes for the development of clinically effective anti-tumor drugs.

Synthesis, Characterization, Antibacterial, Antifungal and Anticorrosion Activities of 1,2,4-Triazolo[1,5-a]quinazolinone

The synthesis of 5,6,7,8-tetrahydro-[1,2,4]triazolo[5,1-b]quinazolin-9(4H)-one (THTQ), a potentially biologically active compound, was pursued, and its structure was determined through a sequence of spectral analysis, including ¹H-NMR, ¹³C-NMR, IR, and HRMS. Four bacterial and four fungal strains were evaluated for their susceptibility to the antibacterial and antifungal properties of the THTQ compound using the well diffusion method. The impact of THTQ on the corrosion of mild steel in a 1 M HCl solution was evaluated using various methods such as weight loss, potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS), and scanning electron microscopy (SEM) analysis. The study revealed that the effectiveness of THTQ as an inhibitor increased with the concentration but decreased with temperature. The PDP analysis suggested that THTQ acted as a mixed-type inhibitor, whereas the EIS data showed that it created a protective layer on the steel surface. This protective layer occurs due to the adsorption behavior of THTQ following Langmuir's adsorption isotherm. The inhibition potential of THTQ is also predicted theoretically using DFT at B3LYP and Monte Carlo simulation.

Synthesis, X-ray Structure, Hirshfeld, DFT and Biological Studies on a Quinazolinone-Nitrate Complex

The reaction of 4-hydroxyquinazoline (4HQZ) with aqueous solution of nitric acid afforded the corresponding quinazolinone-nitrate (4HQZN) complex in very good yield. The crystal structure of 4HQZN was determined and its structural and supramolecular structural aspects were analyzed. 4HQZN crystallized in the space group P21/c and monoclinic crystal system with one [4HQZ-H]+[NO3]- formula and Z = 4. Its supramolecular structure could be described as a 2D infinite layers in which the 4HQZN molecules are connected via N-H…O and C-H…O hydrogen bridges. Using DFT calculations, the relative stability of five suggested isomers of 4HQZN were predicted. It was found that the medium effects have strong impact not only on the isomers' stability but also on the structure of the 4HQZN. It was found that the structure of 4HQZN in DMSO and methanol matched well with the reported X-ray structure which shed the light on the importance of the intermolecular interactions on the isomers' stability. The structure of 4HQZN could be described as a proton transfer complex in which the nitrate anion acting as an e-donor whiles the protonated 4HQZ is an e-acceptor. In contrast, the structure of the isolated 4HQZN in gas phase and in cyclohexane could be described as a 4HQZ…HNO3 hydrogen bonded complex. Biological screening of the antioxidant, anticancer and antimicrobial activities of 4HQZ and 4HQZN was presented and compared. It was found that, 4HQZN has higher antioxidant activity (IC50 = 36.59 ± 1.23 µg/mL) than 4HQZ. Both of 4HQZ and 4HQZN showed cell growth inhibition against breast (MCF-7) and lung (A-549) carcinoma cell lines with different extents. The 4HQZ has better activity with IC50 of 178.08 ± 6.24 µg/mL and 119.84 ± 4.98 µg/mL, respectively. The corresponding values for 4HQZN are 249.87 ± 9.71 µg/mL and 237.02 ± 8.64 µg/mL, respectively. Also, the antibacterial and antifungal activities of 4HQZN are higher than 4HQZ against all studied microbes. The most promising result is for 4HQZN against A. fumigatus (MIC = 312.5 μg/mL).

An overview of triazoloquinazolines: Pharmacological significance and recent developments

Nitrogen heterocyclic rings have participated to constitute most of the drugs and several pharmacologically related compounds. The existence of such hetero atoms/groups in heterocyclic systems privileged specificities in their biological objectives. Particularly, quinazoline and triazole are biologically imperative platforms known to be linked with various pharmacological activities. Some of the prominent pharmacological responses ascribed to these systems are analgesic, antiinflammatory, anticonvulsant, hypnotic, antihistaminic, antihypertensive, anticancer, antimicrobial, antitubercular, antiviral and antimalarial activities. This diversity in the pharmacological outputs for both triazole and quinazoline systems has encouraged the medicinal chemistry researchers to create several chemical routes aiming at the incorporation of two rings in one molecule named triazoloquinazoline system. This system has shown multiple potential activities against numerous targets. Correlation the specific structural features of triazoloquinazoline system with its pharmacological purposes has successively been achieved by performing several pharmacological examinations and structure-activity relationship studies. The development of triazoloquinazoline derivatives and the understanding of their pharmacological targets offer opportunities for novel therapeutics. This review mainly emphases on the medicinal chemistry aspects of triazoloquinazolines including synthesis, reactivity, biological activity and structure activity relationship studies (SARs). Moreover, this review collates literature reported by researchers on triazoquinazolines and provides detailed attention on their analogs pharmacological activities in the perspective of drug development and discovery.

Antifungal Effects of Fusion Puroindoline B on the Surface and Intracellular Environment of Aspergillus flavus

Aspergillus flavus infection is a major issue for safe food storage. In this study, we constructed an efficient prokaryotic expression system for puroindoline B (PINB) protein to detect its antifungal activity. The Puroindoline b gene was cloned into pET-28a (+) vector and expressed in Escherichia coli. Treatment with fusion PINB revealed that it inhibits mycelial growth of A. flavus, a common grain mold. Moreover, fusion PINB-treated A. flavus mycelium withered and exhibited a sunken spore head. As fusion PINB concentration increased, electrical conductivity in mycelium also increased, indicative of cell membrane damage. Furthermore, intracellular malate dehydrogenase and succinate dehydrogenase activity decreased, revealing a disruption in the tricarboxylic acid cycle. Moreover, the dampened activity of the ion pump Na⁺K⁺-ATPase negatively affected the intracellular regulation of both ions. Catalase and superoxide dismutase activity decreased, thus reducing antioxidant capacity, a result confirmed with an increase in malondialdehyde content. Changes to the GSH/GSSG ratio indicated a shift to an intracellular oxidative state. At the same time, laser scanning confocal microscopy assay showed the accumulation of reactive oxygen species and nuclear damage. Therefore, the PINB fusion protein may have the potential to control A. flavus in grain storage and food preservation.

Pyrimido[1,2-a]benzimidazoles: synthesis and perspective of their pharmacological use

The review presents data on the synthesis as well as studies of biological activity of new derivatives of pyrimido[1,2-a]benzimidazoles published over the last decade. The bibliography of the review includes 136 sources.

Discovery of arylamide-5-anilinoquinazoline-8-nitro derivatives as VEGFR-2 kinase inhibitors: Synthesis, in vitro biological evaluation and molecular docking

Herein, we embarked on a structural optimization campaign aiming at the discovery of novel anticancer agents with our previously reported XL-6f as a lead compound. A library of 23 compounds has been synthesized based on the highly conserved active site of VEGFR-2. Several title compounds exhibited selective inhibitory activities against VEGFR-2, which also displayed selective anti-proliferation potency against HepG2 cell. All synthesized compounds were evaluated for anti-angiogenesis capability. Compound 7o showed the most potent anti-angiogenesis ability, the efficient cytotoxic activities (in vitro against HUVEC and HepG2 cell lines with IC₅₀ values of 0.58 and 0.23 µM, respectively). The molecular docking analysis revealed 7o is a Type-II inhibitor of VEGFR-2 kinase. In general, these results indicated these arylamide-5-anilinoquinazoline-8-nitro derivatives are promising inhibitors of VEGFR-2 for the potential treatment of anti-angiogenesis.

Discovery of 6-Arylurea-2-arylbenzoxazole and 6-Arylurea-2-arylbenzimidazole Derivatives as Angiogenesis Inhibitors: Design, Synthesis and in vitro Biological Evaluation

We embarked on a structural optimization campaign aimed at the discovery of novel anti-angiogenesis agents with previously reported imidazole kinase inhibitors as a lead compound. A library of 29 compounds was synthesized. Several title compounds exhibited selective inhibitory activities against vascular endothelial growth factor receptor 2 (VEGFR-2) over epidermal growth factor receptor (EGFR) kinase; these compounds also displayed selective and potent antiproliferative activity against three cancer cell lines. The newly synthesized compounds were evaluated for anti-angiogenesis activity by chick chorioallantoic membrane (CAM) assay. Among them, 1-(2-(2-chlorophenyl)benzo[d]oxazol-5-yl)-3-(4-(trifluoromethoxy)phenyl)urea (compound 5 n) showed the most potent anti-angiogenesis capacity, efficient cytotoxic activities (in vitro against human umbilical vein endothelial cells (HUVEC), H1975, A549, and HeLa cell lines, with respective IC₅₀ values of 8.46, 1.40, 7.61, and 0.28 μm), and an acceptable level of VEGFR-2 kinase inhibition (IC₅₀ =0.25 μm). Molecular docking analysis revealed 5 n to be a type II inhibitor of VEGFR-2 kinase. In general, these results indicate that these 6-arylurea-2-arylbenzoxazole/benzimidazole derivatives are promising inhibitors of VEGFR-2 kinase for potential development into anti-angiogenesis drugs.