Pyrazole derivatives of medically relevant phenolic acids: insight into antioxidative and anti-LOX activity

2020 ◽  
Vol 16 ◽  
Author(s):  
Vesna Milovanović ◽  
Zorica D. Petrović ◽  
Slađana Novaković ◽  
Goran A. Bogdanović ◽  
Dušica Simijonović ◽  
...  
Keyword(s):  
Molecular Docking ◽  
Phenolic Acids ◽  
Active Site ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Radical Scavenger ◽  
Pyrazole Derivatives ◽  
Pyrazole Derivative ◽  
Derivatives Of

Background: From the point of view of medicinal chemistry, compounds containing phenolic and pyrazolic moiety are significant since they are often constituents of bioactive compounds. Objective: The aims of this study were to synthesize pyrazole derivatives of medically relevant phenolic acids, confirm their structure, and evaluate their antioxidative and anti-LOX activities. Methods: Phenolic pyrazole derivatives were obtained starting from esters of medically relevant phenolic acids. The structures of all obtained compounds were determined by NMR and IR spectroscopy, and UV-Vis spectrophotometry. In addition, single-crystal Xray diffraction was used. Pyrazole derivatives were tested for their in vitro antioxidative (DPPH assay), and lipoxygenase (LOX) inhibitory activities. Radical quenching mechanism was estimated using DFT and thermodynamic approach, while molecular docking was used to estimate the binding mode within the enzyme. Results: Pyrazole derivatives were obtained in high yields. Crystal structure of a new compound 3e was determined. Pyrazole derivative with catechol moiety 3d exhibited excellent radical scavenging activity, while compound 3b exhibited the best anti-LOX activity. Molecular docking study revealed that there is no direct interaction of any ligand with the active site of LOX-Ib, but pyrazoles 3a-e behave as inhibitors blocking the approach of linoleic acid to the active site. Conclusion: In this research, protocatechuic and vanillic acid pyrazole derivatives have been obtained for the first time. In vitro antioxidative assay suggests that pyrazole derivate of protocatechuic acid is a powerful radical scavenger, while anti-LOX assay indicates a pyrazole derivative with 4-hydroxyphenyl moiety.

scholarly journals Antioxidant activity of NSAID hydroxamic acids

2009 ◽  
Vol 59 (2) ◽  
pp. 235-242 ◽  
Author(s):  
Marijana Končič ◽  
Zrinka Rajič ◽  
Neva Petrič ◽  
Branka Zorc
Keyword(s):  
Antioxidant Activity ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Iron Chelator ◽  
Hydroxamic Acids ◽  
Radical Scavenger ◽  
Standard Substance ◽  
Metal Chelating ◽  
Inflammatory Drugs ◽  
Derivatives Of

Antioxidant activity of NSAID hydroxamic acidsIn the present study, seven hydroxamic acid derivatives of nonsteroidal anti-inflammatory drugs (NSAIDs) (ibuprofen, fenoprofen, ketoprofen, indomethacin and diclofenac) were found to possess significant antioxidant, radical scavenging and metal chelating activities. The most active antioxidant and radical scavenger wasN-methylhydroxamic acid of diclofenac (ANT= 88.0% andEC50= 60.1 μg mL-1). The activity of the standard substance, butylated hydroxyanisole, in the two assays wasANT= 86.9% andEC50= 18.8 μg mL-1, respectively. Ibuproxam was the strongest iron chelator among investigated hydroxamic acids (EC50= 255.6 μg mL-1), yet significantly weaker than the standard substance, EDTA (EC50= 29.1 μg mL-1). It seems that different mechanism is involved in metal chelating activity than in antioxidant and radical scavenging activity. Antioxidant and radical scavenging activities may be connected with conjugation of the nitrogen lone electron pair with the carbonyl group. On the other hand, more hydrophilic substances tend to be better iron chelators.

Synthesis of Novel Hydrazones of Levofloxacin related molecule and their In Vitro evaluation as antioxidant, and Molecular Docking Studies

2020 ◽  
Vol 23 ◽  
Author(s):  
Bharat B. Kashid ◽  
Jaydeo T. Kilbile ◽  
Kishor D. Wani ◽  
Suhas. M. Pawar ◽  
Vijay M. Khedkar ◽  
...  
Keyword(s):  
Molecular Docking ◽  
In Silico ◽  
Interaction Analysis ◽  
Radical Scavenging Activity ◽  
Research Work ◽  
Radical Scavenging ◽  
Butylated Hydroxytoluene ◽  
Lipinski’S Rule ◽  
Antioxidant Agents

Objective: The research work aims synthesis of novel series of hydrazones, antioxidant screening, evaluate the binding affinities, and in silico methods for the identification of possible drug targets of synthesized compounds. Methods: This report briefly explains the synthesis of novel series of hydrazones was synthesized via. hydrazinolysis of esters to obtain hydrazide, treated with aldehyde and acetophenone to get hydrazones. The spectral confirmed hydrazones exhibited excellent to comparable anti-oxidant as compaired to the standard drugs Butylated hydroxytoluene (BHT) and Ascorbic acid. Molecular docking on myeloperoxidase (MPO) demonstrated the ability of this scaffold to correctly recognize the target and engage in significant bonded and non-bonded interactions with key residues therein. Results and Discussion: In this study, we report an effectively synthesized compounds BK-35, BK-41, BK-26, BK-28 and BK-39 showed the best DPPH radical scavenging activity. The docking results clearly showed the binding mode of hydrazones into the active site of Myeloperoxidase (MPO). An in-silico results, no any of the synthesized compounds BK24 to BK-41 violated Lipinski’s rule of five (miLog P ≤ 5). Conclusions: In vitro preliminary antioxidant screening results in support by in Silico binding affinity data of novel hydrazones of levofloxacin related molecules BK-24 to BK-41 reported here have emerged as excellent antioxidant agents. The inference derived from the in vitro antioxidant screening data and the quantitative insights derived from the per-residue interaction analysis with MPO enzyme, are now being fruitfully utilized for site specific mutation around the nucleus to identify selective and potent antioxidants.

scholarly journals Free Radical Scavenging Activity of Essential Oil of Eugenia caryophylata from Amboina Island and Derivatives of Eugenol

2019 ◽  
Vol 17 (1) ◽  
pp. 422-428 ◽  
Author(s):  
Hanoch Julianus Sohilait ◽  
Healthy Kainama
Keyword(s):  
Free Radical ◽  
Essential Oil ◽  
Biological Activities ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Free Radical Scavenging ◽  
Chemical Compositions ◽  
Free Radical Activity ◽  
Derivatives Of

AbstractEssential oil from Eugenia caryophylata was normally used to heal many different deseaces. Various chemical compositions of essential oil distilled and steamed of Moluccas Eugenia caryophylata has been investigated by many different researchers. Even though an intensive research has been carried out of the local chemotypes, a very detail study has not been fully investigated to find out the complete chemical compounds from the plant essential oil and its content associated with their biological activities. In present paper, we assess the free radical scavenging of E. caryophylata collected from Moluccas islands, Indonesia. Essential oil was extracted from leaves, buds, and stems of plant by steam distillation and analyzed using GC-FID and GC-MS. The result showed that free radical activity of essential oil, main constituent and its derivatives were analized using in vitro method. Essential oil activity from stem obtained as (0.82±0.15 μg/mL) was higher than that from bud and leaf possessing both 1,1-diphenyl-2-picrylhydrazyl (DPPH) and (2,2’-azino-bis-3-ethylbenzthizoline-6-sulphonic acid (ABTS) radical scavenging assays by sinergism of eugenol, eugenyl acetate, β-caryophylene and humulene. The activity of isoeugenol (2) (3.59±0.54 μM) and (5.0±0.53 µM) scavenging DPPH and ABTS, respectively, as derivatives eugenol was higher than (3), (4) and (5). Although (6) was active originally, it was inactive after conversion of the ester. While the change of the double bond of location to conjungation structure caused more activity scavenging radicals than the starting molecule.

Synthesis, Characterization, Antimicrobial and Antioxidant Potential of Diazenyl Chalcones

2018 ◽  
Vol 18 (10) ◽  
pp. 844-856 ◽  
Author(s):  
Harmeet Kaur ◽  
Balasubramanian Narasimhan
Keyword(s):  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Antioxidant Potential ◽  
Dilution Method ◽  
Dpph Assay ◽  
Antimicrobial Potential ◽  
Structural Conformation ◽  
Uv Visible ◽  
Tube Dilution Method

A series of diazenyl chalcones was prepared by base catalyzed Claisen-Schmidt condensation of synthesized hydroxy substituted acetophenone azo dye with various substituted aromatic/ heteroaromatic aldehydes. The structural conformation of synthesized chalcones was done by a number of physicochemical and spectral means like FTIR, UV-visible, mass, NMR spectroscopy and CHNS/O analysis. These diazenyl chalcones were assessed for their in vitro antimicrobial potential against several Gram-negative, Gram-positive bacterial and fungal strains by serial tube dilution method. The fluconazole and cefadroxil were used as standard drugs. The target compounds were also evaluated for their antioxidant potential by DPPH assay. (2E)-3-(2,4-Dichlorophenyl)-1-(4-((2,6- dihydroxyphenyl)diazenyl)phenyl)prop-2-en-1-one (C-7) had shown very good antimicrobial potential with MIC ranges from 3.79 to 15.76 μg/ml against most of the tested microorganisms. Most of the synthesized diazenyl chalcones were found to be active against B. subtilis. The (2E)-1-(5-((2-Chloro- 4-nitrophenyl)diazenyl)-2-hydroxyphenyl)-3-(2-hydroxynaphthalen-1-yl)prop-2-en-1-one (C-10) had shown high free radical-scavenging activity when compared with the ascorbic acid as the reference antioxidant.

α-Glucosidase Inhibition, Antioxidant and Docking Studies of Hydroxycoumarins and their Mono and Bis O-alkylated/acetylated Analogs

2018 ◽  
Vol 15 (2) ◽  
pp. 127-135 ◽  
Author(s):  
Parvesh Singh ◽  
Nomandla Ngcoya ◽  
Ramgopal Mopuri ◽  
Nagaraju Kerru ◽  
Neha Manhas ◽  
...  
Keyword(s):  
In Silico ◽  
Biological Activities ◽  
Wide Spectrum ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Catalytic Site ◽  
Docking Simulations ◽  
In Silico Docking ◽  
Anti Oxidant

Background: Diabetes Mellitus (DM) is a complex metabolic disease illustrated by abnormally high levels of plasma glucose or hyperglycaemia. Accordingly, several α-glucosidase inhibitors have been developed for the treatment of diabetes and other degenerative disorders. While, a coumarin ring has the privilege to represent numerous natural and synthetic compounds with a wide spectrum of biological activities e.g. anti-cancer, anti-HIV, anti-viral, anti-malarial, anti-microbial, anti-convulsant, anti-hypertensive properties. Besides this, coumarins have also shown potential to inhibit α-glucosidase leading to a generation of new promising antidiabetic agents. However, the testing of O-substituted coumarins for α-glucosidase inhibition has evaded the attention of medicinal chemists. Methods: For O-alkylation/acetylation reactions, the hydroxyl coumarins (A-B) initially activated by K2CO3 in dry DMF were reacted with variedly substituted haloalkanes at room temperature under nitrogen. The synthesized compounds were tested for their α-glucosidase (from Saccharomyces cerevisiae) inhibitory activity and anti-oxidant activity using DPPH radical scavenging activity. In silico docking simulations were conducted using CDocker module in DS (Accelrys) to explore the binding modes of the representative compounds in the catalytic site of α-glucosidase. Results: All the coumarin analogues (A1, B1, A2-A10, B2-B8) including their precursors (A-B) were evaluated for their in vitro α-glucosidase inhibition using acarbose as a standard inhibitor. All the mono O-alkylated coumarins (except A1) showed significant (p <0.05) α-glucosidase inhibition relative to the hydroxyl coumarin (A) with IC50 values ranging between 11.084±0.117 to 145.24± 29.22 µg/mL. Compound 7-(benzyloxy)-4, 5-dimethyl-2H-chromen-2-one (A9) bearing a benzyl group (Ph-CH2-) at position 7 showed a remarkable (p <0.05) increase in the activity (IC50 = 11.084±0.117 µg/mL), almost four-fold more than acarbose (IC50 = 40.578±5.999 µg/mL). The introduction of –NO2 group dramatically improved the anti-oxidant activity of coumarin, while the O-alkylation/acetylation decreased the activity. Conclusion: The present study describes the synthesis of functionalized coumarins and their evaluation for α-glucosidase inhibition and antioxidant activity under in vitro conditions. Based on IC50 data, the mono O-alkylated coumarins were observed to be stronger inhibitors of α-glucosidase with respect to their bis O-alkylated analogues. Coumarin (A9) bearing O-benzyloxy group displayed the strongest α-glucosidase inhibition, even higher than the standard inhibitor acarbose. The coumarin (A10) bearing –NO2 group showed the highest anti-oxidant activity amongst the synthesized compounds, almost comparable to the ascorbic acid. Finally, in silico docking simulations revealed the role of hydrogen bonding and hydrophobic forces in locking the compounds in catalytic site of α-glucosidase.

Structure-Based Design, Synthesis, Biological Evaluation and Molecular Docking Study of 4-Hydroxy-N'-methylenebenzohydrazide Derivatives Acting as Tyrosinase Inhibitors with Potentiate Anti-Melanogenesis Activities

2020 ◽  
Vol 16 (7) ◽  
pp. 892-902 ◽  
Author(s):  
Aida Iraji ◽  
Mahsima Khoshneviszadeh ◽  
Pegah Bakhshizadeh ◽  
Najmeh Edraki ◽  
Mehdi Khoshneviszadeh
Keyword(s):  
Molecular Docking ◽  
Active Site ◽  
Competitive Inhibition ◽  
Docking Study ◽  
Biological Evaluation ◽  
Primary Response ◽  
Ratio Method ◽  
Molecular Docking Study ◽  
Metal Chelating

Background: Melanogenesis is a process of melanin synthesis, which is a primary response for the pigmentation of human skin. Tyrosinase is a key enzyme, which catalyzes a ratelimiting step of the melanin formation. Natural products have shown potent inhibitors, but some of these possess toxicity. Numerous synthetic inhibitors have been developed in recent years may lead to the potent anti– tyrosinase agents. Objective: A number of 4-hydroxy-N'-methylenebenzohydrazide analogues with related structure to chalcone and tyrosine were constructed with various substituents at the benzyl ring of the molecule and evaluate as a tyrosinase inhibitor. In addition, computational analysis and metal chelating potential have been evaluated. Methods: Design and synthesized compounds were evaluated for activity against mushroom tyrosinase. The metal chelating capacity of the potent compound was examined using the mole ratio method. Molecular docking of the synthesized compounds was carried out into the tyrosine active site. Results: Novel 4-hydroxy-N'-methylenebenzohydrazide derivatives were synthesized. The two compounds 4c and 4g showed an IC50 near the positive control, led to a drastic inhibition of tyrosinase. Confirming in vitro results were performed via the molecular docking analysis demonstrating hydrogen bound interactions of potent compounds with histatidine-Cu+2 residues with in the active site. Kinetic study of compound 4g showed competitive inhibition towards tyrosinase. Metal chelating assay indicates the mole fraction of 1:2 stoichiometry of the 4g-Cu2+ complex. Conclusion: The findings in the present study demonstrate that 4-Hydroxy-N'- methylenebenzohydrazide scaffold could be regarded as a bioactive core inhibitor of tyrosinase and can be used as an inspiration for further studies in this area.

Curcumin-based antioxidant and glycohydrolase inhibitor compounds: Synthesis and in vitro appraisal of the dual activity against diabetes

2020 ◽  
Vol 16 ◽  
Author(s):  
Sajjad Esmaeili ◽  
Nazanin Ghobadi ◽  
Donya Nazari ◽  
Alireza Pourhossein ◽  
Hassan Rasouli ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Enzyme Inhibitor ◽  
Radical Scavenging Activity ◽  
Curcuma Longa ◽  
Radical Scavenging ◽  
Reducing Power ◽  
Inhibitory Effect ◽  
Curcumin Derivatives ◽  
Reducing Power Assay

Background: Curcumin, as the substantial constituent of the turmeric plant (Curcuma longa), plays a significant role in the prevention of various diseases, including diabetes. It possesses ideal structure features as enzyme inhibitor, including a flexible backbone, hydrophobic nature, and several available hydrogen bond (H-bond) donors and acceptors. Objective: The present study aimed at synthesizing several novel curcumin derivatives and further evaluation of these compounds for possible antioxidant and anti-diabetic properties along with inhibitory effect against two carbohydrate-hydrolyzing enzymes, α-amylase and α-glucosidase, as these enzymes are therapeutic targets for attenuation of postprandial hyperglycemia. Methods: Therefore, curcumin-based pyrido[2,3-d]pyrimidine derivatives were synthesized and identified using an instrumental technique like NMR spectroscopy and then screened for antioxidant and enzyme inhibitory potential. Total antioxidant activity, reducing power assay and 1,1-diphenyl-2-picrylhydrazyl (DPPH• ) radical scavenging activity were done to appraisal the antioxidant potential of these compounds in vitro. Results: Compounds L6-L9 showed higher antioxidant activity while L4, L9, L12 and especially L8 exhibited the best selectivity index (lowest α-amylase/α-glucosidase inhibition ratio). Conclusion: These antioxidant inhibitors may be potential anti-diabetic drugs, not only to reduce glycemic index but also to limit the activity of the major reactive oxygen species (ROS) producing pathways.

The Molecular and Enzyme Kinetic Basis for Altered Activity of Three Cytochrome P450 2C19 Variants Found in the Chinese Population

2020 ◽  
Vol 13 (3) ◽  
pp. 233-244
Author(s):  
Amelia Nathania Dong ◽  
Nafees Ahemad ◽  
Yan Pan ◽  
Uma Devi Palanisamy ◽  
Beow Chin Yiap ◽  
...  
Keyword(s):  
Cytochrome P450 ◽  
Molecular Docking ◽  
Active Site ◽  
Chinese Population ◽  
Accessible Surface Area ◽  
Solvent Accessible Surface Area ◽  
In Vitro Assays ◽  
Access Channel ◽  
Cytochrome P450 2C19

Background: There is a large inter-individual variation in cytochrome P450 2C19 (CYP2C19) activity. The variability can be caused by the genetic polymorphism of CYP2C19 gene. This study aimed to investigate the molecular and kinetics basis for activity changes in three alleles including CYP2C19*23, CYP2C19*24 and CYP2C19*25found in the Chinese population. Methods: The three variants expressed by bacteria were investigated using substrate (omeprazole and 3- cyano-7-ethoxycoumarin[CEC]) and inhibitor (ketoconazole, fluoxetine, sertraline and loratadine) probes in enzyme assays along with molecular docking. Results: All alleles exhibited very low enzyme activity and affinity towards omeprazole and CEC (6.1% or less in intrinsic clearance). The inhibition studies with the four inhibitors, however, suggested that mutations in different variants have a tendency to cause enhanced binding (reduced IC50 values). The enhanced binding could partially be explained by the lower polar solvent accessible surface area of the inhibitors relative to the substrates. Molecular docking indicated that G91R, R335Q and F448L, the unique mutations in the alleles, have caused slight alteration in the substrate access channel morphology and a more compact active site cavity hence affecting ligand access and binding. It is likely that these structural alterations in CYP2C19 proteins have caused ligand-specific alteration in catalytic and inhibitory specificities as observed in the in vitro assays. Conclusion: This study indicates that CYP2C19 variant selectivity for ligands was not solely governed by mutation-induced modifications in the active site architecture, but the intrinsic properties of the probe compounds also played a vital role.

scholarly journals Survey of Phenolic Acids, Flavonoids and In Vitro Antioxidant Potency Between Fig Peels and Pulps: Chemical and Chemometric Approach

Molecules ◽  
2021 ◽  
Vol 26 (9) ◽  
pp. 2574
Author(s):  
Lahcen Hssaini ◽  
Francisca Hernandez ◽  
Manuel Viuda-Martos ◽  
Jamal Charafi ◽  
Rachid Razouk ◽  
...  
Keyword(s):  
Phenolic Acids ◽  
Radical Scavenging ◽  
Fruit Peel ◽  
Mean Values ◽  
Local Cultivar ◽  
Ic50 Values ◽  
The Mean ◽  
Lipid Peroxidation Inhibition ◽  
Almost All

In the present study, chromatic coordinates, phenolic acids, flavonoids and antioxidant capacity assessed by 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonate (ABTS) and lipid peroxidation inhibition capacity (LPIC) essays and their relative IC50 were investigated in 25 fig cultivars growing in Morocco. The aims of this study were to determine (i) the variation in these compounds among light and dark-colored cultivars, (ii) their partitioning between fruit peel and pulp and (iii) to display network connections among these variables. Twelve phenolic compounds (PCs) were isolated in peel extract versus eight in pulp samples. Anthocyanins, mainly cyanidin-3,5-diglucoside and cyanidin-3-O-rutinoside, were the predominant compounds in peels, where the mean concentrations were 75.90 ± 18.76 and 77.97 ± 18.95 µg/g dw, respectively. On the other hand, (−)-epicatechin and cyanidin-3-O-rutinoside were the major compounds in the pulp extracts, where the mean values were 5.23 ± 4.03 and 9.01 ± 5.67 µg/g dw, respectively. A two-dimensional hierarchically clustered heatmap was applied to the dataset to explore correlations in the dataset and similarities between cultivars, without dimensionality reduction. Results showed that anthocyanins, particularly pelargonidin-3-O-rutinoside, cyanidin-3,5-diglucoside and cyanidin-3-O-rutinoside, were the main contributors to the peels’ free radical scavenging capacity. This capacity was particularly higher in the peel of dark-colored figs compared to the fruit pulp. The local cultivar “INRA 1301” showed the most promising phenolic profile due to its very high levels of almost all detected PCs, especially (−)-epicatechin, quercetin-3-O-rutinoside, quercetin-3-O-glucoside, cyanidine-3,5-diglucoside, cyanidine-3-O-rutinoside and pelargonidin-3-O-rutinoside (54.66, 141.08, 35.48, 494.08, 478.66, 12.56 µg/g dw, respectively). Having the darkest figs in the collection (L* = 25.72, c* = 22.09 and h° = 20.99), this cultivar has also combined promising IC50 values, which were of 19.85, 40.58 and 124.78 µg/mL for DPPH, ABTS and LPIC essays, respectively.

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