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To improve the thermodynamic and mechanical properties of asymmetric polyimide (PI), a method to enhance the linearity of PI by using a structural reorganization approach was designed. First, two novel diamines containing benzimidazole and benzoxazole groups, namely PADBZ and PDBOA, were constructed and synthesized. Thereafter, two new kinds of PI films (PADBZ‐PMDA and PDBOA‐PMDA) were prepared and polymerized with 1,2,4,5‐benzenetetracarboxylic anhydride (PMDA). Based on structural reorganization, PADBZ‐PMDA and PDBOA‐PMDA had repeating units of the same chemical composition and different linearity with PABZ‐BPDA and BOA‐BPDA, respectively. Comparing PADBZ‐PMDA and PABZ‐BPDA, due to the transfer in the position of benzene, PADBZ‐PMDA with high linearity showed the improved heat resistance (Tg up to 448°C), dimensional stability (CTE down to 2.3 ppm/K) and mechanical properties. PDBOA‐PMDA and BOA‐BPDA had the same situation. This study provided a unique solution to enhance the performances of PI by increasing the linearity using a structural reorganization approach. [ABSTRACT FROM AUTHOR]

Benzazoles, such as benzoxazoles and benzothiazoles, are compounds with important biological and pharmacological activities and important intermediaries in synthesis. This report presents the synthesis of a butanamide derived from linking 5-chloro-2-aminobenzoxazole and 2-aminobenzothiazole via 4-chlorobutanoyl chloride. The corresponding compound N-(benzothiazol-2-yl)-4-((5-chlorobenzoxazol-2-yl)aminobutanamide was obtained at a 76% global yield using accessible starting materials and a methodology in two reaction steps. Furthermore, we conducted docking studies of this compound on 3-TOP protein to explore its potential as an antidiabetic agent. [ABSTRACT FROM AUTHOR]

Triphenylamine (TPA)‐based Schiff base chemosensors ((E)‐2‐((4‐(diphenylamino)benzylidene)amino)phenol [TPA‐AP], (E)‐5‐(diphenylamino)‐2‐(((2‐hydroxyphenyl)imino)methyl)phenol [HTPA‐AP], and (E)‐5‐(diphenylamino)‐2‐((phenylimino)methyl)phenol [HTPA‐A]) were synthesized and explored the role of metal chelating hydroxyl functionality position for heavy metal ion sensing. TPA‐AP and HTPA‐AP showed Cu2+ ion‐induced chemical transformation and produced oxazole derivatives with turn‐on fluorescence. In contrast, HTPA‐A exhibited metal chelation‐induced turn‐on fluorescence for Zn2+ ion. The reactive chemical sensing of TPA‐AP and HTPA‐AP led to high selectivity of Cu2+, and other ions did not show any interference. The concentration‐dependent studies of Cu2+ and Zn2+ indicated the limit of detection (LOD) up to 6.07 × 10−7 and 4.6 × 10−7 M, respectively. Further, Cr3+, Fe3+, and Fe2+ coordination with TPA‐AP and HTPA‐AP exhibited visible color change from colorless to yellow. However, the yellow color was disappeared and becomes colorless due to imine hydrolysis. Interestingly, all three metal ions showed different rate of hydrolysis and color disappearance. TPA‐AP with Fe3+ exhibited fast hydrolysis and immediate color change whereas Fe2+ and Cr3+ required longer time. But HTPA‐AP and HTPA‐A produced stable complexes with Cr3+, Fe2+, and Sn2+ and Fe3+ alone showed hydrolysis. Thus, the present studies provide structural insight for designing reactive fluorescence and colorimetric Schiff base chemosensor for heavy metal ions. [ABSTRACT FROM AUTHOR]

A straightforward strategy for the synthesis of pharmaceutically active 2‐aminobenzoxazoles and 2‐aminobenzothiazoles is described by using 2‐aminophenols, 2‐aminothiophenols, and functionalized phenylisothiocyanates as the model substrates. The developed method proceeds through the HFIP‐promoted cyclodesulfurization process which allows for the efficient synthesis of these scaffolds at 60 °C of reaction temperature without the addition of a transition metal‐catalyst or hazardous solvents with excellent yields (up to 92 %) of product formation. This process involves HFIP‐mediated hydrogen bonding interactions with the hydroxyl and thiol moieties, leading to bond breaking and formation during the reaction, resulting in the compounds of interest and the in situ release of H2S gas. [ABSTRACT FROM AUTHOR]

This work describes a novel iron‐catalysed approach for the synthesis of aryl‐substituted benzimidazoles and benzoxazoles. The methodology employs reductive carbonylation using readily available aryl iodides and aryl amines as precursors, with carbon monoxide serving as the efficient carbonyl source. The reaction proceeds under mild conditions with the addition of hydrosilanes and bases. Notably, aryl aldehydes are generated in situ from the aryl iodides, which subsequently react with o‐phenylenediamine or 2‐aminophenol to afford the desired products in high yields. The structures of the synthesized benzimidazoles and benzoxazoles were confirmed using 1H and 13C NMR spectroscopy and mass spectrometry. [ABSTRACT FROM AUTHOR]

A copper‐catalyzed one‐pot synthesis of substituted bis(benzoxazole)amine, N‐benzoxazole(benzoimidazole)amine, and N‐benzoxazole(benzothiazole)amine is described via intramolecular cyclization of iodophenol and 2‐amino benzimidazoles(thiazoles)(oxazoles)‐trichloroacetonitrile adduct under ultrasound irradiation in MeCN with good yields. The use of simple and readily available starting materials, no column chromatography, mild copper‐catalytic reaction conditions, good yields (74–84 %), applying the sonochemical methodology and short reaction times are remarkable specifications of this protocol. All the compounds synthesized in this design are new and their identities have been confirmed using IR, NMR, CHN and mass spectrometry techniques. [ABSTRACT FROM AUTHOR]

Ruthenium(II) polypyridyl complexes continue to raise increasing interest for the encouraging results in several biomedical areas. Considering their vast chemical‐physical repertoire, in particular the possibility to switch from the sensitization of reactive oxygen species (ROS) to ROS‐scavenging abilities by tuning the nature of their ligands, it is therefore surprising that their potential as antioxidants has not been largely investigated so far. Herein, we explored the antioxidant behaviour of the novel ruthenium compound [Ru(dbpy)(2,3‐DAN)Cl]PF6 (Ru1), featuring a benzoxazole derivative (dpby=2,6‐bis(4‐methyl‐2‐benzoxazolyl)pyridine) and the non‐innocent 2,3‐diamminonaftalene (2,3‐DAN) ligand, along with the reference tpy‐containing analogue [Ru(tpy)(2,3‐DAN)Cl]PF6 (Ru2) (tpy=2,2':6',2"‐terpyridine). Following the synthesis and the electrochemical characterization, chemical antioxidant assays highlighted the beneficial role of dpby for the ROS‐scavenging properties of Ru1. These data have been corroborated by the highest protective effect of Ru1 against the oxidative stress induced in SH‐SY5Y human neuroblastoma, which exerts pro‐survival and anti‐inflammatory actions. The results herein reported highlight the potential of Ru1 as pharmacological tool in neurodegenerative diseases and specially prove that the antioxidant properties of such compounds are likely the result of a non‐trivial synergetic action involving the bioactive ligands in their chemical architectures. [ABSTRACT FROM AUTHOR]

The impact of the polymeric matrix on the photophysical characteristics of monomeric dyes responsive to excited‐state intramolecular proton transfer (ESIPT) was investigated through UV–Vis absorption as well as steady‐state and time‐resolved emission spectroscopies. For this purpose, two benzoxazole monomers (M1 and M2) with acryloyl groups at different positions in their molecular structures were employed to facilitate covalent bonding within a styrene chain. Our findings reveal significant variations in their excited‐state properties due to the proximity of the acryloyl groups, which affects the energy barrier of the ESIPT reaction, the emission wavelength, and the balance between the normal and tautomeric forms. The experimental results were corroborated through theoretical investigations at the DFT/TDDFT level, specifically using the B3LYP‐D3/def2‐TZVP methodology. Three notable observations emerged: donor/acceptor groups at the meta/para positions induced electron distribution changes, causing red‐shifted emission for M2; in the polymer film, particularly in PM1, intramolecular hydrogen bond deactivation favored N* emission over T* emission; and the zwitterionic character of the T* species. This study underscores the advantages of functionalization in polymers, which can lead to colorless films and prevalent N* or T* emission, and contributes valuable insights into molecular design strategies for tailoring the photophysical properties of polymeric materials. [ABSTRACT FROM AUTHOR]

New coordination polymers were synthesized. A ditopic centrosymmetric organic ligand containing oxazole heterocycles, 4,8-dichlorobenzo[1,2d:4,5d']bis(oxazole)-2,6(3H,7H)-dithione (H2L), was prepared and structurally characterized. It was shown that deprotonated H2L forms non-luminescent binuclear molecular complexes Li2L(THF)6 (I) and Na2L(DME)4 (II) with alkali metals, while complexes of H2L with lanthanides are ionic compounds [Ln(DMSO)8][L]1.5 (Ln = Nd (III), Yb (IV)) exhibiting moderate metal-centered emission in the near-infrared (IR) range, despite the absence of coordination of the ligand L to lanthanide ions. The molecular structures of H2L·2DMSO and I–III were established by X-ray diffraction (CCDC nos. 2320461 (H2L·2DMSO), 2320462 (I), 2320463 (II), 2320464 (III)). [ABSTRACT FROM AUTHOR]

Two new homologous series of mesogenic compounds, alkanoic acid 4-{[4-(6-chloro-benzooxazol-2-yl)-phenylimino]-methyl}-3-hydroxy-phenyl ester (3a-c) and alkcanoic acid 4-(6-chloro-benzooxazol-2-yl)-3-hydroxy-phenyl ester (5a-b) incorporating benzoxazole heterocyclic have been prepared and FT-IR, NMR, and MS spectrometry have been used to study the molecular structures. The mesogenic behaviour was examined using POM, DSC, and PXRD (variable temperature) techniques. To evaluate its impact on thermal behaviour and mesomorphic properties, the imine linking group of derivatives was modified and investigated. Enantiotropic SmA is observed by the members of Series-I, while those of series-II show monotropic SmA mesomorphism. These compounds were also examined for their absorption and fluorescent properties. The absorption and photoluminescence spectra of compounds 3a-c occurred at 345 nm and 410 nm, whereas in the case of 5a-b occurred at 325 nm and 370 nm respectively. The GAUSSIAN-09 programme has been utilised to perform DFT calculations at B3LYP level for the purpose of obtaining the stable electronic structures of 3a and 5a. [ABSTRACT FROM AUTHOR]

Benzoxazoles and benzothiazoles are a class of aromatic heterocyclic compounds having similar ring structures, in which a benzene ring is fused to the 4 and 5 positions of the 1,3-oxazole and 1,3-thiazole rings respectively. They constitute an interesting class of organic compounds due to their powerful and significant biological, agrochemical, pharmaceutical and physicochemical activities. Indeed, benzoxazole and benzothiazole derivatives possess a wide range of applications, such as: anticancer, anti-inflammatory, antioxidant, anticonvulsant, antitubercular, antifungal, pesticidal, anticorrosive, complexing properties and so on. The synthesis of benzoxazole and benzothiazole derivatives has attracted much attention from several researchers across the world and numerous synthetic methods have been developed to access these compounds over the past decades. In this review, we present new and recent synthetic strategies, as well as some biological properties of benzoxazole and benzothiazole derivatives. [ABSTRACT FROM AUTHOR]

Palladium-catalyzed heterylation of monobromophenyl-substituted zinc(II) porphyrin with small heterocycles (benzothiazole, benzoxazole, and N-methylbenzimidazole) was carried out. As a result, unsymmetrical heterylphenyl-substituted zinc(II) porphyrins soluble in organic solvents were obtained. The interaction of heteryl-substituted zinc(II) porphyrins with alpha-helical proteins was studied by spectral methods using bovine serum albumin in aqueous organic solvents. It was found that the titration of the zinc(II) porphyrins with albumin in a sodium phosphate buffer involves a number of equilibria including complexation and aggregation. In the case of porphyrins containing N-methylbenzimidazole and benzoxazole residues, self-aggregation processes initiated by absorption of organic solvent molecules by the protein predominate. It was found that more hydrophobic nature of zinc(II) porphyrin with benzothiazole residue promotes the complex formation with the protein. The photochemical properties of zinc(II) porphyrin with a benzothiazole residue, capacity for the photooxidation of the alpha-helical protein, and the high affinity of protein to this porphyrin make it a promising candidate for the potential applicability for photodynamic inactivation. [ABSTRACT FROM AUTHOR]

Trinuclear metallacyclic oxidovanadium(V) complexes, [{VO(L3+2R)}3] (1–3) with asymmetric multidentate linking ligands (H3L3+2R: R = H, Me, Br), were synthesized. The molecular structure of 1 is characterized as a tripod structure, with each V(V) ion coordinated by ONO-atoms from a tridentate Schiff base site and ON-atoms from a bidentate benzoxazole site of two respective H3L3+2H ligands. The intramolecular V⋯V distances range from 8.0683 to 8.1791 Å. Complex 4 is a mononuclear dioxidovanadium(V) complex, (Et3NH)[VO2(HL3+2H)]. Cyclic voltammograms of 1−3 in DMF revealed redox couples attributed to three single-electron transfer processes. [ABSTRACT FROM AUTHOR]

A series of novel carboxamide compounds containing benzoxazole motif was synthesized through multiple steps, including electrophilic substitution, cyclization, reduction and amide formation. These processes utilized ortho-aminophenol and heptafluoro-2-iodopropane as starting materials. The structures of these compounds (4a–4r) were characterized by 1H NMR, 13C NMR, and HRMS. Bioassay results revealed that most of these compounds exhibited significant insecticidal activity against Mythimna separata at 500 mg/L. Among them, compound 6-chloro-N-(4-methoxy-3-(6-(perfluoropropan-2-yl)benzo[d]oxazol-2-yl)phenyl)-N-methylnicotinamide (4r) possessed the highest activity, even at 4 mg/L. Molecular docking predicted the binding modes of 4r. These novel carboxamide compounds containing benzoxazole motifs offer valuable insights for designing insecticidal compounds targeting GABA receptors, aiming to control lepidopteran pests effectively. [ABSTRACT FROM AUTHOR]

Eight QSAR models (M1–M8) were developed from a dataset of 118 benzo-fused heteronuclear derivatives targeting VEGFR-2 by Monte Carlo optimization method of CORALSEA 2023 software. Models were generated with hybrid optimal descriptors using both SMILES and Graphs with zero- and first-order Morgan extended connectivity index from a training set of 103 derivatives. All statistical parameters for model validation were within the prescribed limits, establishing the models to be robust and of excellent quality. Among all models, split-2 of M5 was the best-fit as reflected by ${\rm{ }}r_{{\rm{validation}}}^2$ r v a lidation 2 , ${\rm{ }}Q_{{\rm{validation}}}^2$ Q v a lidation 2 and ${\rm{MAE}}$ MAE . Mechanistic interpretation of this model assisted the identification of structural descriptors as promoters and hinderers for VEGFR-2 inhibition. These descriptors were utilized to design novel VEGFR-2 inhibitors (YS01-YS07) by bringing modifications in compound MS90 in the dataset. Docking of all designed compounds, MS90 and sorafenib with VEGFR-2 binding site revealed favourable binding interactions. Docking score of YS07 was higher than that of MS90 and sorafenib. Molecular dynamics simulation study revealed sustained interactions of YS07 with key amino acids of VEGFR-2 at a run time of 100 ns. This study concludes the development of a best fit QSAR model which can assist the design of new anticancer agents targeting VEGFR-2. [ABSTRACT FROM AUTHOR]

Breast cancer, a deadly disease among women, demands effective interventions due to its global impact, with over one million annual cases. Current anti-breast cancer drugs displays several side effects, also most patients resists to these drugs during early treatment stage. Hence, global search for better drugs with less side effects became necessary. The objective of this study is to identify potential inhibitors of vascular endothelial growth factor receptor-2 (VEGFR-2), a critical target in breast cancer treatment. Molecular docking-based virtual screening of 45 benzoxazole/thiazole derivatives was conducted, followed by molecular dynamics simulations to explore ligandprotein interactions. Seven ligands (compounds 7, 10, 12, 13, 14, 20, and 26) demonstrated superior binding affinities ranging from -157.85 to -173.88 kcal/mol (MolDock scores) and -109.96 to -129.23 kcal/mol (Rerank scores) compared to Sorafenib (-156.35 kcal/mol MolDock score and -102.63 kcal/mol Re-rank score). Compound 7, identified as a potential hit, exhibited stability in a 100-ns dynamic simulation. It was chosen as a template for designing novel inhibitors, resulting in five compounds with improved binding affinities ranging from -177.84 to -184.69 kcal/mol (MolDock scores) and -137.34 to -143.44 kcal/mol (Re-rank scores). Pharmacological profiling confirmed the drug-like properties of both the potential hit molecules and the designed compounds, with 0-1 violations against Lipinski's rule of five and favorable pharmacokinetics status. Density functional theory (DFT) studies illustrated the reactive nature of the designed compounds. These findings suggest the potential of these molecules as novel VEGFR-2 inhibitors for breast cancer treatment, providing promising prospects for future drug development. [ABSTRACT FROM AUTHOR]

The current paper describes the formation of a new series of platinum(II) complexes with 5,7-di-tert-butyl-2-(thiophen-2-yl)benzo[d]oxazole (btbo) ligand. This study has focused on synthesis methods of some organoplatinum(II) complexes containing btbo ligand from two different reagents under different conditions. Furthermore, a detailed computational study was performed to identify the thermodynamic parameter's behavior. The synthesis was initiated from some complexes including cis-[PtCl2(dmso)2], R1, [PtCl2(COD)], R2 and a benzoxazole derivative as organic ligand 5,7-di-tert-butyl-2-(thiophen-2-yl)benzo[d]oxazole, (btbo). Implementation of the 1H NMR analysis procedure on products reveals two isomers' existence. Moreover, the thermodynamic parameters, (ΔH°, ΔG°, ΔS°), were quantified to achieve a more precise understanding. The energy diagram examination and considering the quantified parameters present the stability and instability of each product which is in notable agreement with the experimental data. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Methyl-2-(4-chlorophenyl)- 5-benzoxazoleacetate (MCBA), a synthetic benzoxazole derivative with established antipsoriatic efficacy, was investigated for potential antinociceptive effects. This study employs various nociceptive assays in mice to elucidate MCBA's antinociceptive mechanisms. MATERIALS AND METHODS: M CBA's a ntinociceptive potential was tested against various nociception models induced by formalin, glutamate, capsaicin, a transient receptor potential vanilloid 1 (TRPV1) receptor agonist, and phorbol 12-myristate 13-acetate, a protein kinase C (PKC) activator. It was then assessed using the hot plate test and examined within the acetic acid-induced writhing test. During the acetic acid-induced writhing test, MCBA was pre-challenged against selective receptor antagonists such as naloxone, caffeine, atropine, yohimbine, ondansetron, and haloperidol. It was also pre-challenged with ATP-sensitive potassium channel inhibitor (glibenclamide) to further elucidate its antinociceptive mechanism. RESULTS: The results showed that oral administration of MCBA led to a dose-dependent and significant inhibition (p < 0.05) of nociceptive effects across all evaluated models at doses of 60, 120, and 240 mg/kg. Moreover, the efficacy of MCBA's antinociceptive potential was significantly counteracted (p < 0.0001) by specific antagonists: (i) directed at adenosinergic, alpha-2 adrenergic, and cholinergic receptors using caffeine, yohimbine, and atropine, respectively; and (ii) targeting ATP-sensitive potassium channels, employing glibenclamide. Antagonists aimed at opioidergic and serotoninergic receptors (naloxone and ondansetron, respectively) had poor utility in inhibiting antinociceptive activity. Conversely, the dopaminergic receptor antagonist haloperidol potentiated locomotor abnormalities associated with MCBA treatment. CONCLUSIONS: MCBA-induced antinociception involves modulation of glutamatergic-, TRVP1 receptors- and PKC-signaling pathways. It impacts adenosinergic, alpha-2 adrenergic, and cholinergic receptors and opens ATP-sensitive potassium channels. [ABSTRACT FROM AUTHOR]

An efficient visible light mediated, eosin Y catalyzed direct C–H oxidative amination of benzoxazoles with secondary amines has been developed, which providing a straightforward, green, and environmentally benign access to a wide variety of substituted benzoxazole-2-amines under mild reaction conditions. The biological studies such as drug-likeness and molecular docking are also carried out on the molecule. [ABSTRACT FROM AUTHOR]

Benzazoles, such as benzoxazoles and benzothiazoles, are compounds with important biological and pharmacological activities and important intermediaries in synthesis. This report presents the synthesis of a butanamide derived from linking 5-chloro-2-aminobenzoxazole and 2-aminobenzothiazole via 4-chlorobutanoyl chloride. The corresponding compound N-(benzothiazol-2-yl)-4-((5-chlorobenzoxazol-2-yl)aminobutanamide was obtained at a 76% global yield using accessible starting materials and a methodology in two reaction steps. Furthermore, we conducted docking studies of this compound on 3-TOP protein to explore its potential as an antidiabetic agent.

A new library of Aryl Isoxazole Incorporated Pyrimidin-2-yl)oxazolo[4,5-b]pyridine compounds 11a-j and their structures were characterized by analytical data. Further, the preliminary anticancer activity of the newly prepared compounds 11a-j was examined against four types of human cancer cell lines, breast cancer (MCF-7), lung cancer (A549), colon cancer (Colo-205) and ovarian cancer (A2780) by utilizing the MTT method. Most of the compounds displayed good to moderate activities as compared with the etoposide used as a positive control. Amon, five compounds 11a, 11b, 11h, 11i and 11j exhibited more potent activity than the positive control. Mainly, compound 11h displayed superior anticancer activity.

This study was aimed to design and synthesize hybrid analogues of benzoxazole bearing thiosemicarbazide analogues 1–15 as promising β-Glucuronidase inhibitory activity using D-saccharic acid 1,4-lactone as the reference inhibitor. The newly afforded benzoxazole-thiosemicarbazide compounds 1–15 displayed a broad range of inhibitory potential with IC50 values ranging from 20.58 ± 2.46 to 87.89 ± 8.43 μM, as compared to D-saccharic acid 1,4-lactone (IC50 = 59.5 ± 5.36 μM). Among the synthesized series, the compounds 14, 2, and 5 demonstrated outstanding β-Glucuronidase inhibitory potential with IC50 values of 20.58 ± 2.46, 25.24 ± 2.34 and 24.53 ± 2.53 μM respectively. Further, the precise structures of synthesized analogues were confirmed using 1H NMR, 13C NMR and HREIMS. Additionally, the molecular docking approach was employed to correlate the in vitro β-Glucuronidase inhibitory activity well with in silico study and result obtained corroborated that active analogues established several key interactions with the active sites of β-Glucuronidase enzyme.

Three homologous series of 3‑hydroxy-4-(((-4-benzoxazol-2-yl)phenyl)imino)methyl)phenyl-4-alkoxybenzoate (with ester linkage) and 5-(alkoxy)-2-(((4-(5-benzoxazol-2-yl)phenyl)imino)methylphenol (without ester linkage) Schiff based derivatives, bearing different substituents at 5 position i.e., 5-methylbenzoxazole, benzoxazole and 5-chlorobenzoxazole units at the end of the molecule and their Copper complexes were synthesised. The molecular structure of all the compounds were elucidated by different spectroscopic techniques such as FT-IR, 1H & 13C NMR and mass spectrometry together with elemental analysis. Their phase transition behaviour was investigated by differential scanning calorimetry, polarizing optical microscopy and X-ray diffraction. The structure-property relationships, compounds bearing a variety of polar substituents and changing the spacer from ester linked to without ester-linked has been studied. Substituents with stronger electron-withdrawing properties gave a wider mesomorphic temperature domain, in the order Cl > CH3 >H.

Abstract Several novel approaches to target Bcl-2 proteins and apoptotic pathways have been identified in recent years for the treatment of different types of cancer including colorectal cancer. However, no effective treatments were yet developed for colorectal cancer. Twenty two novel benzoxazole and thiazole−based compounds were designed, synthesized, and evaluated as potential Bcl-2 inhibitors with anti−proliferative activity. Compounds 8g, 12e and 13d showed good to moderate anti−proliferative activity against most of the NCI 60 cell line panel with mean growth inhibition percent of 45.13, 42.29 and 29.25%, respectively. They showed the greatest cell growth inhibition percent to HCT-116 cell line with the values of 68.0, 59.11 and 43.44%, respectively. The aforementioned compounds were furtherly investigated for their effect on HCT-116 cell cycle, and they showed increase in the total apoptosis with 17, 22, and 5%, respectively. Also, the apoptotic effect of compounds 8g, 12e and 13d, were tested by their effect on altering caspase-3 expression level in HCT-116 human cell line. The three compounds showed an increase in the caspase-3 levels by 6, 8 and 3 folds, respectively in comparison with the same untreated ones. Moreover, they were evaluated for their in–vitro Bcl-2 inhibitory activity and they showed percent inhibition of 60.2, 69.2 and 50.0%, respectively. Finally, the most potent compounds 8g and 12e showed 3.864 and 2.834 folds increase in Bax level compared to the control respectively. On the other hand, Bcl-2 was down−regulated to 0.31 and 0.415 folds compared to the control. The induction of apoptosis through increase in caspase 3 expression and down−regulation of Bcl-2 is the suggested mechanism of action.

Sustainability is one of the hot topics of today's research, in particular when it comes to energy‐storage systems such as batteries. Redox‐active molecules implemented in organic batteries represent a promising alternative to lithium‐ion batteries, which partially rely on non‐sustainable heavy metal salts. As an alternative, we propose benzothiazole, ‐oxazole and ‐imidazole derivatives as redox‐active moieties for polymers in organic (radical) batteries. The target molecules were identified by a combination of theoretical and experimental approaches for the investigation of new organic active materials. Herein, we present the synthesis, electrochemical characterization and theoretical investigation of the proposed molecules, which can later be introduced into a polymer backbone and used in organic polymer batteries. [ABSTRACT FROM AUTHOR]

Lysine-specific demethylase 1 (LSD1/KDM1A) has emerged as a promising therapeutic target for treating various cancers (such as breast cancer, liver cancer, etc.) and other diseases (blood diseases, cardiovascular diseases, etc.), owing to its observed overexpression, thereby presenting significant opportunities in drug development. Since its discovery in 2004, extensive research has been conducted on LSD1 inhibitors, with notable contributions from computational approaches. This review systematically summarizes LSD1 inhibitors investigated through computer-aided drug design (CADD) technologies since 2010, showcasing a diverse range of chemical scaffolds, including phenelzine derivatives, tranylcypromine (abbreviated as TCP or 2-PCPA) derivatives, nitrogen-containing heterocyclic (pyridine, pyrimidine, azole, thieno[3,2-b]pyrrole, indole, quinoline and benzoxazole) derivatives, natural products (including sanguinarine, phenolic compounds and resveratrol derivatives, flavonoids and other natural products) and others (including thiourea compounds, Fenoldopam and Raloxifene, (4-cyanophenyl)glycine derivatives, propargylamine and benzohydrazide derivatives and inhibitors discovered through AI techniques). Computational techniques, such as virtual screening, molecular docking and 3D-QSAR models, have played a pivotal role in elucidating the interactions between these inhibitors and LSD1. Moreover, the integration of cutting-edge technologies such as artificial intelligence holds promise in facilitating the discovery of novel LSD1 inhibitors. The comprehensive insights presented in this review aim to provide valuable information for advancing further research on LSD1 inhibitors. [ABSTRACT FROM AUTHOR]

The article discusses the use of benzoxazole and benzothiazole as directing groups for palladium- and ruthenium-catalyzed C-H arylation reactions. The authors explore different reaction conditions and catalysts to achieve selective arylation of these compounds. They also investigate the effects of substituents on the aryl unit and the benzoxazole/benzothiazole moiety. The document provides valuable information for researchers interested in the synthesis and functionalization of heterocyclic compounds. Additionally, the document includes experimental procedures and characterization data for specific compounds synthesized using the methods discussed. [Extracted from the article]

The use of ligand combination approach in the Pd catalyzed direct C−H arylation of benzothiazole and benzoxazole is demonstrated. The combination of two ligands phenanthroline monohydrate (Phen.H2O) and triphenylphosphine (PPh3) with Pd‐catalyst have offered the best catalytic properties in the C−H bond arylation reactions than either of two ligands employed separately in the reactions. This protocol exhibits a wide substrate scope affording C2 arylated benzothiazole and benzoxazole derivatives in excellent yields. Mechanistic studies including kinetic isotope effect (KIE), H/D exchange and competition experiments show that the C−H bond activation of benzothiazole and benzoxazole is very facile under reaction conditions. Furthermore, different mechanistic pathways originated from the catalytically active species such as Pd(η2‐dba)L (dba=dibenzylidene acetone) and Pd(PPh3)2 were investigated using computational methods. The computational results suggest that the generation of catalytically active species from Pd2(dba)3 is endoergic process and Phen ligand can initiate this step. On the other hand, the presence of PPh3 could be crucial for the oxidative addition of aryl halides which is the rate‐determining step of the reaction. [ABSTRACT FROM AUTHOR]

Several novel approaches to target Bcl-2 proteins and apoptotic pathways have been identified in recent years for the treatment of different types of cancer including colorectal cancer. However, no effective treatments were yet developed for colorectal cancer. Twenty two novel benzoxazole and thiazole−based compounds were designed, synthesized, and evaluated as potential Bcl-2 inhibitors with anti−proliferative activity. Compounds 8g, 12e and 13d showed good to moderate anti−proliferative activity against most of the NCI 60 cell line panel with mean growth inhibition percent of 45.13, 42.29 and 29.25%, respectively. They showed the greatest cell growth inhibition percent to HCT-116 cell line with the values of 68.0, 59.11 and 43.44%, respectively. The aforementioned compounds were furtherly investigated for their effect on HCT-116 cell cycle, and they showed increase in the total apoptosis with 17, 22, and 5%, respectively. Also, the apoptotic effect of compounds 8g, 12e and 13d, were tested by their effect on altering caspase-3 expression level in HCT-116 human cell line. The three compounds showed an increase in the caspase-3 levels by 6, 8 and 3 folds, respectively in comparison with the same untreated ones. Moreover, they were evaluated for their in–vitro Bcl-2 inhibitory activity and they showed percent inhibition of 60.2, 69.2 and 50.0%, respectively. Finally, the most potent compounds 8g and 12e showed 3.864 and 2.834 folds increase in Bax level compared to the control respectively. On the other hand, Bcl-2 was down−regulated to 0.31 and 0.415 folds compared to the control. The induction of apoptosis through increase in caspase 3 expression and down−regulation of Bcl-2 is the suggested mechanism of action. [ABSTRACT FROM AUTHOR]

A series of benzamide derivatives containing quinoxaline and benzoxazole fragments were synthesized and characterized by 1H NMR and mass spectra. The antibacterial activity of the synthesized derivatives was tested in vitro against gram-positive and gram-negative bacterial strains using an agar well diffusion assay. The molecular docking study showed good docking scores between –9.85 and –7.8 kcal/mol against DNA gyrase (PDB ID: 4KTN). [ABSTRACT FROM AUTHOR]

Background: The foundation of this study lies in the multifaceted pharmacological activities of benzoxazole, prompting structural modifications that have yielded diverse compounds with therapeutic potential. Notably, the exploration of the Azabenzoxazole Triazole Derivative (ATD) adds a unique dimension, with the incorporation of triazole into the benzoxazole structure offering prospects for central nervous system (CNS) actions. This investigation focuses on the synthesis and evaluation of ATD, emphasizing its potential antidepressant properties and highlighting the strategic role of biologically potent molecules in drug discovery. Materials and Methods: The experimental approach utilized Wistar albino rat as subjects, housed ethically and provided standard care. Ethical committee approval guided the study. A five-day experimental protocol involved groups treated with control (normal saline, 2 ml/kg p.o.), Fluoxetine (20 mg/kg), and ATD (50, 100, and 200 mg/kg, I.P.) for both forced swimming and tail suspension tests. These behavioural assays, recognized paradigms for antidepressant activity, were employed to assess the CNS stimulatory effects of ATD. Results: Statistical analysis, encompassing ANOVA (One-way) followed by Tukey's HSD, revealed significant and dose-dependent reductions in immobility time during both the forced swimming and tail suspension tests. The data, considered at a 5% level of significance (P = 0.05), demonstrated the noteworthy antidepressant activity of ATD. The doses of 50, 100, and 200 mg/kg exhibited substantial effects in both models. Conclusion: Azabenzoxazole Triazole Derivative (ATD) emerges as a promising antidepressant agent, evidenced by a significant and dose-dependent reduction in immobility time during behavioural tests on Wistar albino rat. This study underscores the potential of ATD in the realm of antidepressant drug development, emphasizing its role as a biologically potent compound. Further exploration is warranted to elucidate the underlying mechanisms and optimize its therapeutic application. [ABSTRACT FROM AUTHOR]

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Covalent organic frameworks (COFs) have emerged as efficient heterogeneous photocatalysts for a wide range of relatively simple organic reactions, whereas their application in complex organic transformations, like site‐selective functionalization of unactivated C−H bonds, is underexplored, which can be mainly attributed to the lack of highly active organophotocatalytic cores. Herein through bonding oxygen atoms at the N‐terminus of quinolines in nonsubstituted quinoline‐linked COFs (NQ−COFs), we successfully realized the embedding of active hydrogen atom transfer (HAT) moieties into the skeleton of COFs. This novel designed COF (NQ−COFE5−O), serving as both an excellent photosensitizer and HAT catalyst, exhibited much higher efficiency in C−H functionalization than the corresponding NQ−COFE5. Specially, we evaluated the photocatalytic performance of NQ−COFE5−O on ten different substrates, including quinolines, benzothiazole, and benzoxazole, all of which were transferred to desired products in moderate to high yields (up to 93 %). Furthermore, the as‐synthesized NQ−COFE5−O displayed excellent photostability and could be reused with negligible loss of activity for five catalytic cycles. [ABSTRACT FROM AUTHOR]

2-(2-Carboethoxy-3,4-dichloro-6-hydroxyphenyl)benzoxazole exhibits a number of chromogenic properties including solvatochromism and photochromism. Solvatochromic properties are due to the existence of keto–enol equilibrium and dissociation equilibrium. T-type negative photochromism is a two-step process of Z–E photoisomerization and the subsequent intramolecular proton transfer in the ground state to form the enol form. The multiemission profile is created by a number of isomeric forms, among which the enol form exhibits the most intense fluorescence with an anomalous Stokes shift due to intramolecular proton transfer in the excited state. [ABSTRACT FROM AUTHOR]

A series of pleuromutilin analogs containing substituted benzoxazole were designed, synthesised, and assessed for their antibacterial activity both in vivo and in vitro. The MIC of the synthesised derivatives was initially assessed using the broth dilution method against four strains of Staphylococcus aureus (MRSA ATCC 43300, S. aureus ATCC 29213, clinical isolation of S. aureus AD3 and S. aureus 144). Most of the synthesised derivatives displayed prominent in vitro activity (MIC ≤ 0.5 µg/mL). Compounds 50 and 57 exhibited the most effective antibacterial effect against MRSA (MIC = 0.125 µg/mL). Furthermore, the time-kill curves showed that compounds 50 and 57 had a certain inhibitory effect against MRSA in vitro. The in vivo antibacterial activity of compound 50 was evaluated further using a murine thigh model infected with MRSA (–1.24 log10CFU/mL). Compound 50 exhibited superior antibacterial efficacy to tiamulin. It was also found that compound 50 did not display significant inhibitory effect on the proliferation of RAW 264.7 cells. Molecular docking study revealed that compound 50 can effectively bind to the active site of the 50S ribosome (the binding free energy −7.50 kcal/mol). [ABSTRACT FROM AUTHOR]

The four-membered ruthenium(II) organometallics Ru(η2-RL)(PPh3)2(CO)(Cl) (1) where η2-RL = C6H2O-2-CHNHC6H4R(p)-3-Me-5 and R = CH3 reacts with 2-(2-hydroxyphenyl)benzothiazole (Hhpbt) and 2-(2-hydroxyphenyl)benzoxazole (Hhpbo) in refluxing ethanol to afford Ru(PPh3)2(CO)(hpbt)Cl (2) and Ru(PPh3)2(CO)(hpbo)Cl (3) respectively in excellent yield. In the course of these reactions, the Ru − C(aryl) bond in 1 is cleaved, and the RL ligand is no longer coordinated with the metal center in the products. The spectral (UV–vis, IR, 1H NMR) and electrochemical data of the complexes are reported. The identity of complex 2 has been established by single-crystal X-ray structure determination. The electronic structure and the absorption spectra of the complexes are scrutinized by DFT and TD-DFT analyses. The complexes were also tested for their ability to exhibit DNA-binding activity. [ABSTRACT FROM AUTHOR]

New 2-(4-(fluorosulfonyloxy)phenyl)benzoxazole (2) was synthesized through the SuFEx click reaction in a two-chamber reactor. The effect of silylation on the yield of the target compound was investigated. The fluorescent properties of compound 2 were determined using experimental and computational methods. [ABSTRACT FROM AUTHOR]

In this study, two types of ortho-oxazine functionalized bismaleimides with exceptional thermal properties and solubility were synthesized. The excellent solubility in many solvents is attributed to the stable twisted structure of the monomer. The monomer containing the cyano group showed enhanced solubility. It was found that the curing mode of ortho-oxazine functionalized bismaleimide was autocatalytically cured. In situ FT-IR spectroscopic studies indicated that the structure of bismaleimide resin undergoes a structural transformation at higher temperatures to form benzoxazole resin with enhanced thermal stability. The carbon residue rates of bismaleimide and benzoxazole resins at 800°C were 69% and 77%, respectively. The new bismaleimide and benzoxazole resins were analyzed using Microscale Combustion Calorimeter (MCC), and it was found that they also possess excellent flame-retardant properties, specifically benzoxazole resin. [ABSTRACT FROM AUTHOR]

In the present work, mononuclear copper(II) complexes [Cu(L1)Cl](1) and [Cu(L2)Cl](2) having meridional tridentate "NNO" ligands with different substituents have been synthesized and the complexes were characterized by different analytical and spectral techniques, namely FT-IR, NMR, and UV-Vis spectral studies. Molecular structures of complexes 1 and 2 were determined by single-crystal X-ray crystallography. These complexes have been utilized as a catalyst for the synthesis of substituted benzoxazole derivatives under mild conditions. A total of 34 benzoxazole derivatives having different substituents were prepared. The mechanism of this multicomponent reaction, catalysed by complexes 1 and 2, was investigated and the proposed reaction mechanism was based on H-atom abstraction by the phenoxyl radical complex. [ABSTRACT FROM AUTHOR]

A novel sterically hindered o-benzoquinone 4,6-di-tert-butyl-3-(5,7-di-tert-butylbenzooxazole-2-yl)-o-benzoquinone containing a benzoxazole moiety is prepared. The interaction of this quinone with Cu(0) yielded a cubane copper(II) complex with a Cu4O4 core. Molecular and crystal structures of the o-quinone (CCDC 2269708) and the copper complex (CCDC 2269709) are determined by XRD. [ABSTRACT FROM AUTHOR]

In this study, 24 chalcone derivatives containing benzoxazole were designed and synthesized, and the structures of all target compounds were confirmed by NMR and HRMS. The results of antibacterial activity showed that the median effective concentration (EC50) value of Z2 against Xanthomonas oryzae pv.oryzae (Xoo) was 8.10 μg/mL, which was better than thiodiazole copper (60.62 μg/mL), the antibacterial activity of Z2 was verified by scanning electron microscopy (SEM). Antibacterial mechanism of Z2 on Xoo was preliminarily explored, and the results showed concentrations were 100, 50 mg/L, which had a good cell membrane permeability to Xoo and can inhibit the EPS content and the production of extracellular enzymes, affecting the formation of biofilm, preliminary validation of the antibacterial effect of Z2 on Xoo. At 200 mg/L, Z2 had a better protective activity on harvested potatoes, which was comparable with thiodiazole copper. The activity against tobacco mosaic virus (TMV) was determined with half leaf dry spot method. The EC50 value of curative activity of Z15 was 101.97 μg/mL, which was superior to ningnanmycin (NNM) 294.27 μg/mL, and the EC50 value of protective activity of Z16 was 104.05 μg/mL, which was superior to NNM 185.73 μg/mL. Molecular docking results showed Z15, Z16 had a significantly higher affinity with tobacco mosaic virus coat protein (TMV-CP) than NNM. The above results indicated that chalcone derivatives containing benzoxazole have the potential to become antibacterial and antivirial agents.

A series of pleuromutilin analogs containing substituted benzoxazole were designed, synthesised, and assessed for their antibacterial activity both in vivo and in vitro. The MIC of the synthesised derivatives was initially assessed using the broth dilution method against four strains of Staphylococcus aureus (MRSA ATCC 43300, S. aureus ATCC 29213, clinical isolation of S. aureus AD3 and S. aureus 144). Most of the synthesised derivatives displayed prominent in vitro activity (MIC ≤ 0.5 µg/mL). Compounds 50 and 57 exhibited the most effective antibacterial effect against MRSA (MIC = 0.125 µg/mL). Furthermore, the time-kill curves showed that compounds 50 and 57 had a certain inhibitory effect against MRSA in vitro. The in vivo antibacterial activity of compound 50 was evaluated further using a murine thigh model infected with MRSA (–1.24 log10CFU/mL). Compound 50 exhibited superior antibacterial efficacy to tiamulin. It was also found that compound 50 did not display significant inhibitory effect on the proliferation of RAW 264.7 cells. Molecular docking study revealed that compound 50 can effectively bind to the active site of the 50S ribosome (the binding free energy −7.50 kcal/mol).

New 2-(4-(fluorosulfonyloxy)phenyl)benzoxazole (2) was synthesized through the SuFEx click reaction in a two-chamber reactor. The effect of silylation on the yield of the target compound was investigated. The fluorescent properties of compound 2 were determined using experimental and computational methods.

Alzheimer's disease (AD) is treated by targeting cholinesterase enzymes like acetylcholinesterase and butyrylcholinesterase, and these enzymes' inhibitors serve as important tools for treatment of alzheimer diseases. Hybrid analogues with a 1,3-oxazole moiety based on benzoxazole were designed, developed, and then tested for their cholinesterase inhibition. All the newly synthesized analogues showed moderate to good inhibitory potentials having IC50 values raging between 0.90 ± 0.05 µM to 35.20 ± 0.70 µM against acetylcholinesterase and 1.10 ± 0.10 µM to 37.70 ± 0.60 µM against butyrylcholinesterase enzymes. Among the series, the analogue 11 (IC50 = 0.90 ± 0.05 µM), (IC50 = 1.10 ± 0.10 µM) and 18 (IC50 = 1.20 ± 0.05 µM), (IC50 = 2.10 ± 0.10 µM) being the strongest acetylcholinesterase and butyrylcholinesterase inhibitors as compared to standard donepezil drug. Nonetheless, the remaining analogues also displayed better inhibition profile against both these targeted enzymes. Furthermore, the structures of all the synthesized analogues were confirmed by using HREI-MS, 1HNMR and 13CNMR spectroscopy. Additionally, molecular docking experiments were conducted to determine the potential mode of interaction between the majority of active analogues and the enzyme active site. The findings corroborated the experimental data.

Spirocyclic compounds have been extensively studied in recent years. Due to their wide variety of properties, they have a broad range of industrial and pharmacological applications. This has stimulated interest in the synthesis of new derivatives. The aim of the current contribution was to synthesize new multifunctional spirocyclic compounds from tetrahydrobenzoxazolones, which served as versatile starting products for the elaboration of more complex molecules. The spirocyclic compounds were then functionalized in different ways. [ABSTRACT FROM AUTHOR]

Positive-tone photosensitive poly(o-hydroxyamide) (PHA) precursors were synthesized from the polycondensation reaction of 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane (Bis-AP-AF), 4,4'-oxybisbenzoyl chloride (OBC) and three mono-functional amines as end-cappers. The synthesized PHA precursors were characterized and converted to polybenzoxazoles (PBOs) by thermal cyclization reaction. The photoresist formulations composed of the prepared PHA precursor and diazonaphthoquinone (DNQ) photoactive compound were prepared, and the photolithographic properties of the photoresist formulations were investigated by UV light irradiation, followed by a 2.38 wt.% tetramethylammonium hydroxide (TMAH) solution treatment in terms of the chemical structure of end-cappers. The dissolution rate at 2.38 wt.% TMAH solution by various UV light exposure doses and the shrinkage ratio by thermal cyclization of micro-patterns by UV light irradiation and developing process from the photoresist formulations are affected by the chemical structure of end-cappers. [ABSTRACT FROM AUTHOR]

A series of soluble thermosetting polyimide resins containing benzoxazole structure were synthesized by two-step polymerization using 4-phenylethynylphthalic anhydride (4-PEPA) as the end-capping reagent, 2-(4-aminophenyl)-5-aminobenzoxazole (BOA) and 3,4′-diaminodiphenyl ether (3,4′-ODA) as the aromatic diamines, and 4,4′-(hexafluoroisopropylidene) diphthalic anhydride (6FDA) as the aromatic dianhydride. The imide oligomers were characterized by employing Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), solubility tests and rheological measurements. Thermosetting polyimides derived from the imide oligomers were then produced via a thermal cross-linking reaction of the phenylethynyl group. The thermal and mechanical properties of the thermosets were studied using thermogravimetric analysis (TGA), dynamic mechanical thermal analysis (DMA), and mechanical property measurements. The effects of chemical architectures and molecular weights of the imide oligomers on processability, thermostability and mechanical properties were systematically investigated. The results showed that all the copolymerized imide oligomers possessed good solubility in organic and low melt viscosity, and the corresponding thermosets exhibited high glass transition temperature (up to 401°C) and 5% weight-loss temperature (up to 533°C) in an air atmosphere while excellent mechanical properties (flexural strength up to 217 MPa and elongation at break up to 11.2%). With the increase of the concentration of the benzoxazole group, the imide oligomers of PI-X-2 (-O-, -BO-, -B-) exhibited less solubility and higher minimum melt viscosity but improved glass transition temperature after curing and mechanical properties of their thermosets. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is a progressive neurological illness that is distinguished clinically by cognitive and memory decline and adversely affects the people of old age. The treatments for this disease gained much attention and have prompted increased interest among researchers in this field. As a springboard to explore new anti-Alzheimer's chemical prototypes, the present study was carried out for the synthesis of benzoxazole-oxadiazole analogues as effective Alzheimer's inhibitors. In this research work, we have focused our efforts to synthesize a series of benzoxazole-oxadiazole (1–19) and evaluating their anti-Alzheimer properties. In addition, the precise structures of synthesized derivatives were confirmed with the help of various spectroscopic techniques including 1H-NMR, 13C-NMR and HREI-MS. To find the anti-Alzheimer potentials of the synthesized compounds (1–19), in vitro acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE), inhibitory activities were performed using Donepezil as the reference standard. From structure-activity (SAR) analysis, it was confirmed that any variation found in inhibitory activities of both acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) enzymes were due to different substitution patterns of substituent(s) at the variable position of both acetophenone aryl and oxadiazole aryl rings. The results of the anti-Alzheimer assay were very encouraging and showed moderate to good inhibitory potentials with IC50 values ranging from 5.80 ± 2.18 to 40.80 ± 5.90 µM (against AChE) and 7.20 ± 2.30 to 42.60 ± 6.10 µM (against BuChE) as compared to standard Donepezil drug (IC50 = 33.65 ± 3.50 µM (for AChE) and 35.80 ± 4.60 µM (for BuChE), respectively. Specifically, analogues 2, 15 and 16 were identified to be significantly active, even found to be more potent than standard inhibitors with IC50 values of 6.40 ± 1.10, 5.80 ± 2.18 and 6.90 ± 1.20 (against AChE) and 7.50 ± 1.20, 7.20 ± 2.30 and 7.60 ± 2.10 (against BuChE). The results obtained were compared to standard drugs. These findings reveal that benzoxazole-oxadiazole analogues act as AChE and BuChE inhibitors to develop novel therapeutics for treating Alzheimer's disease and can act as lead molecules in drug discovery as potential anti-Alzheimer agents. [ABSTRACT FROM AUTHOR]