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Diethyl 2-(((4-methyl-2-oxo-2H-chromen-7-yl)oxy)methylene)malonate (2) was synthesized from coumarin 1 and diethyl ethoxymethylene malonate in ethanol, followed by cyclization in diphenyl ether to give chromene-9-carboxylate (3). Sugar hydrazones 5a-c were formed by reacting hydrazide 4 with D-galactose, D-mannose, and D-xylose, then acetylated to per-O-acetyl derivatives 6a-c. Heating 5a-c with acetic anhydride at 100 °C gave oxadiazolines 7a-c. Compound 8, obtained by refluxing 4 with carbon disulfide, was alkylated to 9 or reacted to give 10. Further reactions yielded acetoxy derivative 13 and hydroxy derivative 14. Compounds 17a-e and 18a-e were synthesized using thiomorpholinophenyl ureido/thioureido-s-triazine. These compounds were characterized and evaluated for antibacterial activity against Gram (+ve) bacteria (B. subtilis, S. aureus) and Gram (-ve) bacteria (E. coli, P. aeruginosa) in addition to yeast-like fungi (C. albicans). Compounds 11, 13, 15, 16, 17c-e, and 18a-e showed the highest antibacterial activity. Molecular docking was performed to study their binding with transpeptidases.

In this manuscript, we are motivated to investigate the reaction site-selectivity for the hydrazo thiazole derivatives (6a–c) with different types of active methylene groups such as malononitrile, and ethyl cyanoacetate. Based on their structural investigations and spectrum data, the results of these reactions have been established to be iminopyridazines (7a–c) and 6-oxopyridazine derivatives (8a–c). We tested the ability of the newly synthesized pyridazine derivatives to inhibit the microbes and COVID-19 proteins. Human coronavirus 229E (HCoV-229E) was used to investigate the antiviral efficacy of prepared compounds. Green monkey kidney (Vero-E6) cell lines were used to investigate MTT and cytopathic effect (CPE). The new 6-oxopyridazine derivatives (8a–c) revealed significant inhibitory efficacy and were capable of inhibiting the human coronavirus 229E. Moreover, the antimicrobial result showed that compounds iminopyridazine (7c) followed by iminopyridazine (7a) followed by iminopyridazine (7b) exhibited excellent antimicrobial properties toward all utilized strains, usually greater than that of common reference drugs, with MIC values ranging from 13 to 21 ppm, from 9 to 14 ppm, and from 8 to 19 ppm whereas, the remaining substances appeared to be promising effective. Structure-activity relationship (SAR) revealed that pyridazine scaffolds containing NH group, as well as substituted electron withdrawal group (Cl) in para-position for benzene ring attributed to thiazole moiety have the best activity. The current study successfully illustrated the possible application of heterocyclic derivatives with pyridazie nucleus including thiazole ring as the main compound in the development of dual antiviral (COVID-19) and antibacterial pharmaceuticals in the future.

Eight thiazolyl-thienyl and thiazolyl-thiadiazolyl ketones 5a-d and 6a-d were synthesized based on the reaction of 5-(2-bromoacetyl)-4-methyl-2-(methylamino)thiazole (2) and/or N-(4-chlorophenyl)-2-(4-methyl-2-(methylamino)thiazol-5-yl)-2-oxoacetohydrazonoyl bromide (3) with four various thiocarbamoyl compounds 4a-d. The synthesized thiazolyl-thienyl and thiazolyl-thiadiazolyl ketones were optimized using DFT approach offered analogous models in which the thiazolyl, thienyl and thiazolyl nuclei have a planar structure. The HOMO and LUMO of studied hybrids have been consisted mainly of the π- and π*-orbitals of the whole molecule, respectively. Hence, the thiazolyl-thiadiazolyl ketones revealed smaller energy gap (ΔEH-L) than the thiazolyl-thienyl derivatives and may be sorted as 5c

New thieno[2,3-b]pyridine clubbed various thiazole ring systems were synthesized by the reaction of 2-(1-(3-amino-4,6-dimethylthieno[2,3-b]pyridin-2-yl)ethylidene)hydrazine-1-carbothioamide with chloroacetone, phenacyl chloride, and chloroacetic acid. The molecular modeling of the synthesized compounds using DFT/B3LYP methodology revealed that all have a low HOMO and LUMO energies, −4.85 - −5.52 and −2.79 - −3.62, respectively, where the compound 10 has the highest values. The targeting thienopyridine analogues with various thiazole moieties 3–10 was assessed in order to create new antimicrobial agents and compared with ampicillin, gentamicin and miconazole as reference antibacterial and antifungal drugs. Compounds 8–10 exhibited potent antimicrobial activity against Gram positive S. aureus, Gram Gram negative E. coli bacteria, and C. albicans (antifungal), with IC50 (18.9 ± 0.63––24.3 ± 0.74 µg/mL), (14.2 ± 0.41––19.5 ± 0.64 µg/mL), and (19.2 ± 0.58–––23.4 ± 0.65 µg/mL), respectively. Furthermore, Molecular docking stimulation on MOE program was applied to expect the effect and interactions of the newly thienopyridine analogues and E. coli DNA gyrase B as it expressed by PDB ID: 1AJ6.

A series of various substituted thiazole-pyrazole hybrids 5, 7, 8, and 9 were synthesized, and their chemical structures were confirmed by spectral data (infrared, 1H & 13C NMR and Mass). The frontier molecular orbital structural and energetic properties of the targeting thiazole-pyrazole hybrids were explored using the DFT/B3LYP methodology. The data indicated that they had a low energy gap (ΔEH-L), 1.51–2.42 eV, and may be sorted as 6 9 > 7 > 6. Meanwhile, most of the synthesized analogues displayed a significant reduction for the activity of the CAIX inhibitor, with IC50 = 0.071 ± 0.015 to 0.902 ± 0.043 µM. Likewise, they revealed an IC50 = 0.119 ± 0.043 to 0.906 ± 0.04 µM for CAXII inhibitor. Moreover, the newly synthesized thiazole-pyrazole analogues were exposed to the theoretical molecular docking study with PDB:1RHJ as the crystal structure of caspase-3 to examine their antiapoptotic effect as well as their certain properties on the caspase-3 enzyme.

Three novel azo thiazole organic dyes, NA-1–3, have been synthesized and utilized as co-sensitizers in dye-sensitized solar cells (DSSCs). These co-sensitizers were designed with a thiazole ring π-bridge that mediates between the diazo (–N = N–) functional group and carboxylic acid anchoring unit. They possess a rod-like molecular structure and exhibit strong UV–vis absorption near 600 nm. Co-sensitization studies were also conducted with the ruthenium complex N719. The co-sensitized DSSCs showed enhanced short-circuit and open-circuit photocurrents (Jsc) and voltages (Voc), resulting in more efficient photovoltaic performance compared to N719 (PCE 7.25%). Electrochemical impedance spectroscopy (EIS) and incident photon to current efficiency (IPCE) were employed to investigate the underlying reasons for these improvements. It was found that co-sensitization effectively reduced electron recombination, resulting in a higher Voc without compromising photocurrent loss.

The reaction of 3-amino-5-phenylaminopyrazoles 2 with 3-(dimethylamino) acrylonitrile derivatives resulted in a series of substituted pyrazolopyrimidine analogues 4 and 6. The DFT studies of the isolated compounds showed that the frontier molecular orbitals energy gap was close and in the 2.65–2.81 eV range where the derivative 6b has the lowest and both of 4a and 4c have the highest values. Meanwhile, the anticancer activity of the newly synthesized pyrazolopyrimidine analogues have been tested against several different cell lines (MCF-7, PC3, Hep-2 and WI38). The investigated pyrazolopyrimidines showed remarkable cytotoxicity activity against the MCF-7 and Hep-2 cell lines. In comparison to the effects of 5-fluorouracil, IC50 = 10.19 ± 0.42 and 7.19 ± 0.47, compounds 6a-c demonstrated potential anticancer activity with IC50 values for MCF-7 (10.80 ± 0.36–19.84 ± 0.49 μM) and Hep-2 (8.85 ± 0.24–12.76 ± 0.16 μM). Important details regarding the protein's binding sites were disclosed when the produced analogues docked with the crystal structure of the KDM5A protein, which was located in the protein data library.

The chromophore 2-(3-cyano-4-((2-(4,6-dimethyl-5-nitro-1H-pyrazolo[3,4-b]pyridin-3-yl) hydrazono)methyl)-5,5-dimethylfuran-2(5H)-ylidene)malononitrile (PPHTCF) was synthesized through coupling of diazotized 3-amino-4,6-dimethyl-5-nitropyrazolo[3,4-b]pyridine with 3-cyano-2-(dicyanomethylene)-4,5,5-trimethylfuran (TCF). The absorption solvatochromism behaviour of PPHTCF, in various solvents, presented ΔEmax = +5.40 where the positive sign suggested red shift occurrence, implying that the PPHTCF has more polar lowest excited state than its ground one. While, the PPHTCF fluorescence spectra afforded λem, in 575–633 nm range, and was more dependent on the solvent polarity than the absorption λmax, despite both exhibited red shift by 58 and 42 nm, respectively. To discover the PPHTCF solvatochromism behaviour in term of “Stokes’ shift”, both of Lippert-Mataga and linear solvation-energy relationship (LSER) formulations have been utilized and the outcomes endorsed that the later was better than the former (R2 = 0.9728). Finally, TD-DFT simulated absorption and emission spectra in EtOH revealed that λmax has been resulted mainly from HOMO → LUMO; HOMO-5 → LUMO and HOMO-2 → LUMO transitions, respectively.

Novel organogelators based on fluorescent alkoxy-substituted 1,4-diarylated 1, 2, 3-triazoles are reported. The findings monitored in the current study promoted the development of inventive compacted supramolecular architectures generated by self-assembly of the prepared triazole-based organogelators. The synthesis, characterization and gelation properties of the current novel alkoxy-substituted 1,4-diarylated 1, 2, 3-triazole arms were described. The synthesis procedures were accomplished by using Cu-catalyzed azide-alkyne cycloaddition (CuAAC) of alkoxy-substituted aryl azide with aryl bearing terminal alkyne subtituents and alkoxy chains of different lengths. The alkoxy-substituted of 1, 4-diarylated 1, 2, 3-triazole derivatives bearing different alkoxy chains were characterized by FTIR, 1H/13C NMR, and elemental analysis. The 1, 4-diarylated 1, 2, 3-triazoles with longer alkoxy terminal groups demonstrated improved gelation properties compared to those with shorter alkoxy terminals. The morphologies of the self-assembled alkoxy-substituted 1, 4-diarylated 1, 2, 3-triazoles were investigated using scanning electron microscopy (SEM), which demonstrated arrangements of highly ordered nanofibers, forced by π-stacks and van der Waals interactions. The antibacterial activity and cytotoxicity of the newly synthesized triazoles was investigated to verify the potential use of the present triazole gelators for a variety of applications, such as drug delivery.

A new hydrazide ligand was prepared to synthesize Ni(II), Hg(II) and UO2(II) complexes, which elucidated by all possible tools. Accordingly, 1M:2L molar ratio was suggested for Ni(II) and Hg(II) complexes, while UO2(II) complex close to 1:1 ratio. The ligand binds as a bidentate or tridentate mode either as a monobasic via deprotonation of azomethine group or as a neutral with Hg(II) complex. A square-planer geometry was suggested for [Ni(L)2], while the other complexes reveal octahedral geometry. The antimicrobial screening was performed as well as the antioxidant and cytotoxic activity test towards Ehrlich ascites cells. The ligand and its Ni(II) complex produce a notable inhibition for microorganisms, while their antioxidant and cytotoxicity are up to the standards themselves. The DFT/B3LYP and Hartree-Fock (HF) methods were used to optimize the structures under suitable basis sets to obtain essential parameters and 3D-maps. Utilizing Swiss-ADME link reveals the positive response of the ligand to blood brain barrier and human intestinal absorption. Moreover, other silico tests were performed via Pharmacophore and Molecular Operating Environmental module (MOE) against different proteins. Finally, the agreement between vitro and silico results was noticed with the ligand and its Ni(II)complex.

Aromatic nucleophilic substitution (SNAr) reactions have been known to be regioselective to the para position on a variety of substituted perfluorobenzenes. In the current study, a series of fluoroaryl 1, 3, 4-oxadiazole derivatives substituted with different para terminal ethers were synthesized using SNAr chemistry to afford fluorescent and thermally reversible low molecular weight organogelators (LMWOs). SNAr was used to synthesize these highly fluorinated organogelators in high purity and good yields starting from pentafluorobenzoic acid and 4′-hydroxy-4-biphenylcarbonitrile. These fluorinated 1, 3, 4-oxadiazole derivatives were characterized by elemental analysis, FTIR, and 1H, 13C, and 19F NMR spectroscopy. The photophysical properties of those organogelators were described. Both UV–visible absorption and fluorescence spectral profiles displayed a solvatochromic and solvatofluorochromic properties. The absorption maxima for the developed organogelators were monitored in the range of 260–289 nm, whereas the emission maxima were monitored in the range of 278–305 nm. The best gelation properties were monitored for the hexyloxy-substituted 2-(biphenylyl)-5-(perflurophenyl)-1, 3, 4-oxadiazole gelator in different solvents with critical gel concentrations in the range of 1.86–5.07 mM. The self-assembly process was monitored to occur via van der Waals forces and π-π stacks to result in gelation of solvents. Scanning electron microscope (SEM) demonstrated nanofiber-like structures (350–550 nm). The thermal stability of the hexyloxy-substituted organogel was monitored at 48 °C. Both cytotoxicity and antimicrobial activity of the produced fluoroaryl 1, 3, 4-oxadiazole derivatives were explored to verify their potential use for biomedical applications, such as drug delivery and bioimaging.

New pyrazole derivatives were prepared and used to synthesize new bioactive agents from Cu(II) complexes that have OSN donors. Analytical and spectral (IR, UV-Vis, MS, 1H NMR, ESR & XRD) instruments characterized these complexes as well as their corresponding ligands. The bonding mode has been modified from ligand to ligand and the molar ratio for isolated complexes has also varied (1:1/1:2, M:L). The geometry of isolated complexes was commonly proposed, based on electronic transitions and ESR spectral-parameters. Via computational approaches, these structures were optimized using standard programs (Gaussian 09 & HyperChem 8.1) under the required basis set. Consequently, important physical characteristics have been obtained after finishing the optimization process. Inhibition behavior of all new synthesizes was studied by MOE module as in-silico approach which conducted versus the crystal structure of NUDT5 protein (6gru) of breast cancer cells. The interaction features summarized from docking processes, reveal effective inhibition validity for new Cu(II) complexes versus breast cancer cells. This according to scoring energy values and the stability of docking complexes in true interaction path (bond length ≤3.5 Å) particularly with Cu(II)-L3 and Cu(II)-L4 complexes. This reflects the possibility of successful behavior during practical application through in-vitro assay that intended in this study. Finally, the degree of toxicity of such new compounds to the breast cancer cell line was determined by in-vitro screening. To judge perfectly on their toxicity, in-vitro screening must compared to positive control as Doxorubicin (reference drug). IC50 values were calculated and represent Cu(II) complexes as outstanding cytotoxic agents which revealed superiority on the reference drug itself.

Polyester textiles have been applied in numerous industrial applications. Polyester fibers are characterized with being excellent insulators to electricity, having excellent flexural and impact strength, ease of manufacture, low‐cost, as well as having resistance to moisture and chemicals. However, polyester fibers cannot be stained due to the absence of active dyeing sites on the surface of the fibrous structure. Thus, polyester cannot be dyed after it has been extruded. Herein, we report the development of novel‐colored polyester fabrics using plasma‐assisted dyeing and anthocyanin natural probe for determination of ammonia that may cause severe harmful effects to human organs and even death. Anthocyanin was extracted from red cabbage and characterized. The water‐soluble anthocyanin was fastened to polyester fibers by mordant (potash alum) to generate anthocyanin–mordant coordinative complex nanoparticles. Polyester can be treated with thin layer of anthocyanin probe after activation with plasma. The results showed excellent colorfastness, ultraviolet blocking, and antibacterial performance of the anthocyanin‐dyed polyester (APET) fibers. The APET fibers showed great potential for developing a portable colorimetric device for an on‐site detection of ammonia. APET displayed a detection limit of aqueous ammonia in the range of 25–200 ppb, displaying a change in color from purple (542 nm) to white (387 nm). [ABSTRACT FROM AUTHOR]