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The 2-cyano-3-(indol-3-yl)acryloyl chloride, a building block synthon prepared in good yield, was utilized for the synthesis of various indolylacrylamide and indole-based heterocycles. Thus, the aforementioned acid chloride was allowed to react with various oxygen, sulfur, and nitrogen nucleophiles, in addition to mono- and bidentate nucleophiles. The pyrazolidine derivatives were produced on interactions with phenylhydrazine and 2-cyanoethanohydrazide. The antioxidant activity of the synthesized compounds was assessed using the phosphomolybdenum technique and ascorbic acid as a standard. The findings displayed that indolyl-based azine, pyrazolidine, cyanoacetamide, and benzodiazepine derivatives were the most active antioxidants. [ABSTRACT FROM AUTHOR]

Rapid and inexpensive one-pot multicomponent synthesis of 1H-pyrazolo[1,2-b]phthalazine-5,10-dione through a condensation reaction of aryl aldehyde, malononitrile or ethyl cyanoacetate and phthalhydrazide catalyzed by water extract of papaya bark ash (WEPBA) solvent medium under microwave irradiation is described. The catalytic medium is used environmentally friendly, and provides several benefits of being simple, inexpensive, high yield, simple work-up and not required hazardous solvent for the reaction. Some of the selected derivatives were characterized by FT-IR, 1H-, and 13C-NMR, and mass spectrometry techniques. The oxidation-reduction properties of the synthesized compounds (4b, 4e, 4f, 4i, and 4k and 6f, 6g, 6h, 6i, and 6j) were studied using cyclic voltammetry (CV). The voltammetry peak current for the oxidation-reduction of the compounds examined at different scan rates. Further, some of the selected 1H-pyrazolo[1,2-b]phthalazine-5,10-dione derivatives were evaluated in vitro antioxidant activity using DPPH assay method. The result appears that, compounds 4b, 4e, 4i, 6f, 6g, and 6h possess significant antioxidant properties in comparison with the ascorbic acid reference. [ABSTRACT FROM AUTHOR]

A straightforward and effective strategy for the synthesis of novel 7-cyano-4-imino-3-phenyl-6-(pyrrolidin-1-yl)-2-substituted-3,4-dihydroselenopheno[3,2-d]pyrimidines have been accomplished through a base-promoted cascade addition/cyclization sequence employing phenyl isothiocyanate followed by the S-alkylation of the obtained fused Se-containing heterocyclic framework with various alkyl halides. Free radical scavenging activity of the synthesized selenium-containing structures was studied against DPPH, as well. Antioxidant activities as IC50 values were ranged from 12.19 to 91.08 µM. Unfused 3-amino-2,4-dicyano-5-(pyrrolidin-1-yl)selenophene was much more powerful antioxidant agent than ascorbic acid. Moreover, the promising antioxidant potentials were observed with selenopheno[3,2-d]pyrimidines. Taking into account the best antioxidant activity of S-benzylated derivative amongst pyrimidine-fused heterocycles and significant relationship between antioxidant activity of compounds and many of their biological potencies, using benzyl halides bearing electron donating groups on phenyl ring can probably improve their antioxidant capacities to make them more effective anti-cancer, anti-diabetic, anti-inflammatory and anti-neurodegenerative agents. [ABSTRACT FROM AUTHOR]

In this work, we have described an efficient one-pot three-component preparation of 2-amino-4H-chromene by the reaction of aromatic aldehyde (1), malononitrile, or ethylcyanoacetate (2), and α or ꞵ-naphthol or resorcinol (3) in the presence of catalyst Water Extract of Orange Fruit Peel Ash agro-waste extracted solvent medium (4 mL) with few drops of ethanol as co-solvent accelerated by microwave irradiation. The reaction is optimized by various methods such as magnetic stirring, mechanochemical, ultrasound, and microwave irradiation, but the microwave irradiation in 180 W power gave excelled yield and faster rate product isolation (4–5 min). The method developed found eco-friendly, metal-free, chemical-less, and solvent-less, inexpensive, and facile approach for the synthesis of 2-amino-4H-chromene derivatives. The final product isolated recrystallized in ethanol, and characterized by FT-IR, 1H-, and 13C-NMR and LC-MS spectrometry techniques. Some of the selected chromene derivatives are subjected to antioxidant activity with concentration range 200–1,000 µg/µL by 2,2-diphenyl-1-picrylhydrazyl method. The derivatives 4a, 4 g, 4h, 6a, 6b, 6c, 8a, and 8f showed antioxidant activities and were comparable to standard ascorbic acid used. Further, studies on electrochemical behavior of selected chromene derivatives (4e, 4f, 4 g, 4i, 6c, 6f, 8d, and 8f) by cyclic voltammetry technique with 50 mVs−1, and revealed that, some of these molecules are good oxidation and reduction potential. [ABSTRACT FROM AUTHOR]

To develop potent anticancer agents, a series of novel 1,3,4-thiadiazoldiazenylacrylonitrile derivatives 2–16 were designed and synthesized using (1,3,4-thiadiazol-2-yl) carbonohydrazonoyl dicyanide (2) as starting material. The radical scavenging activity of the synthesized compounds was evaluated, and it was observed that the compounds have radical scavenging properties. For studying the radical scavenging activity of the synthesized compounds, the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method was applied. It was found that compounds 12–16 are the most potent antioxidant compounds compared to the results of ascorbic acid (reference drug). Cytotoxicity studies of the newly synthesized compounds were performed against two mammalian cancer cell lines, HepG2, and MCF-7 cells. Compound 15 showed an IC50 value (11.5 ± 0.6 µM) that is very similar to DOX as a standard for the two used cell lines. The most promising values were observed from compounds 5 and 12–16 (very strong activity). Histopathology of liver tissues treated with compound 15 confirmed its anticancer activity. Molecular docking (MD) simulations were run to evaluate the putative binding ability of the most promising anti-cancer synthesized compounds 5 and 12–16 with the human cyclin-dependent kinase 2 (CDK2). Based on MD results as well as physicochemical and pharmacokinetic (ADMET) predictions, the compounds under investigation are promising candidates for the future development of novel anticancer agents targeting CDK2. [ABSTRACT FROM AUTHOR]

Series of new thirteen annulated heterocyclic were prepared and screened for their antioxidant activities. The ethyl-4(2-cyanoacetamido)benzoate as a multifunctional component which possess both electrophilic and nucleophilic centers that were utilized in organic synthesis of different candidates. These new compounds studied as antioxidants at different concentrations based on DPPH and ABTS assays using ascorbic acid as a standard antioxidant. The most potent compound was 5 that recorded as the best antioxidant compound with IC50 equal 0.006 mg/ml for DPPH results. While for ABTS study, compound 4 anticipated the best result with IC50 equal 27.46 µM. Different reactive and thermodynamic descriptors were calculated as a preliminary step for a comparative thermodynamic study for antioxidant property. The results clarified that the potent compounds showed dependence on SET–PT mechanism than HAT or SPLET mechanism. These mechanisms depended on different parameters as proton affinity and electron transfer energy that were studied. SET–PT mechanism was dependent on two descriptors: IP and BDE which were studied and observed that were less-valued in site A for two potent compounds 4 and 5. [ABSTRACT FROM AUTHOR]

A new series of various N-(1-(2-chlorobenzo[h]quinolin-3-yl)-1-substituted-vin-2-yl)benzamide derivatives was designed and synthesized based on the 2-chlorobenzo[h]quinoline core as potential antioxidant and insecticidal agents. In vitro antioxidant activities of these compounds were evaluated and compared with commercial antioxidant (ascorbic acid). The results showed good antioxidant activities of these compounds. In addition, in vitro insecticidal activities revealed that most of these compounds exhibited high insecticidal activity against cotton leafworm compared with chlorpyrifos. Some compounds in these series were better than the commercial insecticidal, chlorpyrifos. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs) widely exist in food, which potentially harm human health. This study compared the effect of apple polyphenol (AP) and three antioxidants – ascorbic acid, tert-butyl hydroquinone and butylated hydroxytoluene on barbecued pork. The inhibition pathway of PAHs in barbecued pork were investigated by measuring DPPH radical scavenging rate, peroxide value (POV), and thiobarbituric acid value (TBARs). The results indicated that AP and antioxidants showed positive effects in inhibiting of PAHs formation (20.03–37.36%), scavenging DPPH radical activity (48.56–64.37%), reducing POV value (45.08–64.89%), and TBARs value (13.74–32.72%). Based on strong correlation between the PAHs content and the POV (r = 0.844, p = 0.017) and TBARs values (r = 0.825, p = 0.022) analyzed by Pearson correlation, AP can be used to control the formation of PAHs. The inhibition effect of AP on PAHs showed concentration-dependent. OPLS-DA analysis revealed that 0.20% AP had the best inhibition on PAH in barbecued pork, and elasticity, cohesiveness, adhesion, chewiness, and recovery of barbecued pork were improved significantly. [ABSTRACT FROM AUTHOR]

p-Fluorophenacyl chloride (1) was used as a building block for the preparation of new tetra-substituted thiophene derivatives. The basic-catalyzed reaction of 1 with various thiocarbamoyl compounds such as 2-acetyl-2-substituted-thioacetanilides 2a,b, 3-arylazo-4-mercapto-4-phenylamino-buten-2-ones 5a–c, ethyl 2-arylazo-3-mercapto-3-phenylamino-acrylates 8a–c, N-aryl-2-cyano-3-mercapto-3-phenylamino-acrylamides 11a–c, N-aryl-2-(mercapto(phenylamino)methylene)-3-oxo-butanamides 14a–c, and 2-mercapto-4,6-dimethylnicotinonitrile 17 led to the production of their corresponding substituted thiophene compounds 4a–b, 7a–c, 10a–c, 13a–c, 16a–c, and 19 in moderate yields. The newly synthesized thiophene compounds were deduced according to FTIR, 1H NMR, 13C NMR, 19F NMR, and mass analyses along with micro-analytical data. The synthesized thiophene compounds were tested to evaluate their antibacterial and antioxidant activities. The majority of the synthesized thiophenes showed good to moderate anti-bacterial and antioxidant activities. The hydroxythiophene compound 4a showed extremely high antibacterial activity with inhibition zones 15–21 mm (from 60 to 87.5% activity indices). It inhibits bacterial growth and approaches the activity of Ampicillin, which inhibits bacteria with areas of inhibition from 23 to 25 mm. The hydroxythiophene compound 4a showed excellent antioxidant properties (85.9%) relative to the reference, Ascorbic acid (88.0%). [ABSTRACT FROM AUTHOR]

A carbamate-linked-bistriazole (5) was prepared by click reaction of diethynyl 1,3-phenylenedicarbamate (2) and phenyl azide derivative (4) in DMF/H2O using copper sulfate and sodium ascorbate as a catalyst at room temperature for fluoride ion sensing. The structural analysis of synthesized compound was done by using 1HNMR, 13C NMR, FTIR and HRMS. The sensing behavior of carbamate-linked-bistriazole (5) was examined by 1HNMR, UV–vis and fluorescence study. NMR titration study suggested the participation of triazole, amide and aromatic protons in binding of fluoride ion. UV–visible study established the 1:1 complexation ratio between sensor 5 and F– ion with stability constant K of 2.64 × 104 M−1 and detection limit in µM range (9.372 µM). Further, fluorescence titration for 5 (9.2 × 10−6 M) with fluoride ions exhibited an emission quenching at 424 nm along with small bathochromic shift. Density functional theory (DFT) calculations also confirmed interaction mechanism in 5a-F– complex established by, UV–visible, 1H NMR and fluorescence studies. [ABSTRACT FROM AUTHOR]

An efficient method developed for the synthesis of asymmetric (S)-N-benzylidene-2-(benzyloxy)-1-(5-(pyridin-2-yl)-1,3,4-thiadiazol-2-yl)ethanamine derivatives with excellent yield in short reaction time. The antioxidant and antimitotic activities were estimated and strongly correlated with the potential of Ascorbic acid and Methotrexate respectively. All the synthesized molecules were characterized using various spectral techniques including FTIR, 1H NMR, 13C NMR, and Mass spectrometry. The drug-likeness properties were studied using in silico ADME parameters. All the compounds have an acceptable range of values which indicated good drug-like characteristics based on Lipinski's rule of five and to be orally active. The present method is quite easy along with simple operation and offers many benefits including short reaction time, easy work-up, excellent yield, reduced waste production as well as cost effective. In addition structure-activity relationships of AP-1 to AP-10 derivatives have been described. [ABSTRACT FROM AUTHOR]

A new series of 6-oxo-1,6-dihydropyrimidin-5-carboxamides (4a–m) has been synthesized and reported with good yields. All these compounds were characterized using various spectral techniques such as IR, 1H NMR, 13C NMR, and HRMS and then subjected to in-vitro anti-oxidant and anti-bacterial activities using DPPH and microdilution methods, respectively. Among the synthesized pyrimidine-5-carboxamides, compounds 4a–b, 4j, and 4i were found to exhibit promising antibacterial activity compared to the standard drug Neomycin. Similarly, compounds 4g–i and 4l displayed excellent anti-oxidant activities against the standard drug ascorbic acid. [ABSTRACT FROM AUTHOR]

A new series of coloring compounds (pigments) based on 5-(2-aminothiazol-5-yl)thiazol-2-amine and 5-(4-aminophenyl)thiazol-2-amine as heterocyclic alternatives for benzidine based on disazo dyestuffs were synthesized. All the newly synthesized pigments are characterized based on their physical, spectral, and analytical data. The antimicrobial activity showed that introducing the heterocyclic analogues thiazole (mono or bis) exhibited less toxic and resisted antimicrobial (five gram-positive strain, three gram-negative, and three fungal species). Thus, derivatives demonstrated moderate to good activity compared with Gentamycin and Ketoconazole. Furthermore, the pigments screened for their in vitro antioxidant properties by the DPPH method, and the newly designed pigments PG4–PG11 with thiazole moiety causes increase antioxidant properties with IC50 values ranged between (0.054–0.192 µM) compared with PG1, PG2, and PG3 (IC50 = 0.712, 0.239, and 0.191 µM) as well as Ascorbic acid (IC50 = 2.532 µM). Further, the synthesized pigments' cytotoxicity activity evaluated against HepG-2 and showed IC50 values ranged between (53.52–94.05 µM) compared with PG1–PG3 (IC50 =216.04–393.58 µM) and doxorubicin (IC50 = 8.17 µM). Molecular docking study concluded that thiazole moiety might be made one or more binding mode as critical hydrogen bonding through the nitrogen of thiazole, as well as arene-cation and/or arene-arene interaction with dihydrofolate reductase (DHFR) active site in 1DLS protein. [ABSTRACT FROM AUTHOR]

Present work involves the green and environmentally benign synthesis of 1,5-benzodiazepines using iodine as a catalyst and PEG-400 as a green solvent at room temperature that gives an excellent yield of products. All the synthesized compounds were screened for their anti-inflammatory, antioxidant, and antidiabetic activity. All the synthesized compounds showed excellent antioxidant activity against DPPH and H2O2 radicals as compared to standard ascorbic acid and even more than standard for SOR and NO radicals. Compound 5h showed the highest % anti-inflammatory activity i.e., 80.73% among the series that was comparable to standard diclofenac sodium whereas compound 5d showed the highest antidiabetic activity i.e., 60.46% which was found potent as compared to standard acarbose. [ABSTRACT FROM AUTHOR]

A new series of 1-(6-amino-3,5-dicyano-4-(substituted)pyridin-2-yl)-4-methylthiosemicarbazide derivatives 4(a–i) was achieved by the reaction of malononitrile and 4-methyl-3-thiosemicarbazide with various aldehydes. All the newly designed compounds were structurally established by various analytical methods (IR, 1H, 13C NMR, and HRMS). Further, all the entitled derivatives were evaluated for their potential antioxidant activity by DPPH radical method in which standard, ascorbic acid, was used for comparison and results revealed that the derivatives, 4a and 4i exhibited the highest antioxidant effect. [ABSTRACT FROM AUTHOR]

A new series of 1-Thiazolyl-2-Pyrazolines 5a-g was accomplished by reacting pyrazolealdehyde with an appropriate aromatic ketone in the presence of PEG-300 as a solvent to yield chalcone. The chalcones reacted with thiosemicarbazide to yield asymmetric 1-thiocarbamoyl pyrazoles. The above formed 1-thiocarbamoyl pyrazoles reacted with appropriate α- haloketones to yield 1-Thiazolyl-2-Pyrazolines. The structural interpretations of newly formed compounds were done by 1H NMR, 13CNMR, IR and mass spectroscopic methods. The newly prepared asymmetric 1-Thiazolyl-2-pyrazoline derivatives were evaluated to their in vitro antioxidant (H2O2, DPPH, SOR and NO radical inhibiting activity) as well as anti-inflammatory activity. The 1-Thiazolyl-2-pyrazoline derivatives 5a-g exhibited moderate to good H2O2 scavenging activity as match up to ascorbic acid. All the 1-Thiazolyl-2-pyrazoline derivatives exhibited excellent SOR scavenging activity except 5 b. All the tested compounds have shown good to excellent, NO radical inhibiting activity. DPPH radical scavenging activity results have shown low antioxidant activity. Also, all the 1-Thiazolyl-2-pyrazoline derivatives were tested for their in vitro anti-inflammatory activity. The compounds 5a, 5 b, 5c, 5f and 5 g were exhibited good anti-inflammatory activity and 5d showed moderate activity while 5e less active as match up to diclofenac sodium as a standard reference. [ABSTRACT FROM AUTHOR]