Experimental and theoretical investigation of new 1,3,4-oxadiazole based dioxovanadium (VO+2) complexes and their in-vitro antimicrobial potency

The antimicrobial resistance is a global human threat which has led to the withdrawal of antibiotics from the market. Therefore, it is a need to develop new and effective antimicrobial agents to overcome this problem. In this paper, new Dioxovanadium(V) complexes (1–8) with ligands viz. (2-(5-phenyl-1,3,4-oxadiazole-2-yl)phenol; L1) and 2,5-bis(2-hydroxyphenyl)-1,3,4-oxadiazole (L2) were synthesized and assessed for antimicrobial-activity. Both a bidentate and tetradentate oxadiazole ligands coordinate with vanadium ions through the nitrogen and oxygen atoms giving octahedral geometries. Thermal analysis and IR data confirmed the presence of hydrated water in the metal-complexes. The investigated compounds were assessed for antimicrobial viz four strains of bacterial and one a fungal strain. The antibacterial data showed that, the complexes (1–8) are lower potency against bacterial strain than the free ligands except (5) and (7) complexes. These complexness showed the highest antibacterial potency via the Staphylococcus aureus. All investigated compounds were inactive against C. albicans except complexes 2 and 5 which showed high activity. The performance of DFT was conducted to examine an interaction mode of the target compounds with biological system. The QSPR was calculated as: optimization geometries, (FMOs), and chemical-reactivities for the synthesized compounds. The (MEPs) were figured to predict the interaction behavior of the ligand and its complexes against the receptor. The molecular docking was performed against DNA gyrase to study the interaction mode with biological system.

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Synthesis and Evaluation of Some Novel Chromone Based Dithiazoles as Antimicrobial Agents

International Journal of Medicinal Chemistry ◽

10.1155/2013/815453 ◽

2013 ◽

Vol 2013 ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

Naureen Aggarwal ◽

Vishal Sharma ◽

Harpreet Kaur ◽

Mohan Paul Singh Ishar

Keyword(s):

Antimicrobial Activity ◽

Elemental Analysis ◽

Antimicrobial Agents ◽

Fungal Strain ◽

Bacterial Strains ◽

Standard Drug ◽

Fungal Strains ◽

Inhibitory Potential ◽

C Nmr

Novel substituted 1,2,4-dithiazolylchromones 3a–j were synthesized by the reaction of 3-formylchromones (1a–j) with two equivalents of p-chlorothiobenzamide (2) in dry xylene and characterized spectroscopically (IR, 1H and 13C NMR, mass) and elemental analysis. All synthesized compounds were screened for in vitro antimicrobial activity against various pathogenic bacterial and fungal strains and were found to possess good to moderate inhibitory potential against all tested strains. Antimicrobial results reveal that compounds bearing lipophilic electron withdrawing groups such as chloro and bromo displayed significant inhibitory potential against both bacterial and fungal strains. Particularly, compound 3c displayed significant inhibitory against bacterial strains and compound 3h exhibits significant inhibitory potential in comparison to standard drug fluconazole against fungal strain S. cerevisiae.

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Synthesis, Identification, Computer-Aided Docking Studies, and ADMET Prediction of Novel Benzimidazo-1,2,3-triazole Based Molecules as Potential Antimicrobial Agents

Molecules ◽

10.3390/molecules26237119 ◽

2021 ◽

Vol 26 (23) ◽

pp. 7119

Author(s):

Huda R. M. Rashdan ◽

Aboubakr H. Abdelmonsef ◽

Mortaga M. Abou-Krisha ◽

Tarek A. Yousef

Keyword(s):

Antimicrobial Activity ◽

Binding Energy ◽

Antimicrobial Agents ◽

Sodium Ethoxide ◽

Dna Gyrase ◽

Docking Studies ◽

Bacterial Strains ◽

Standard Drug ◽

E Coli

2-azido-1H-benzo[d]imidazole derivatives 1a,b were reacted with a β-ketoester such as acetylacetone in the presence of sodium ethoxide to obtain the desired molecules 2a,b. The latter acted as a key molecule for the synthesis of new carbazone derivatives 4a,b that were submitted to react with 2-oxo-N-phenyl-2-(phenylamino)acetohydrazonoyl chloride to obtain the target thiadiazole derivatives 6a,b. The structures of the newly synthesized compounds were inferred from correct spectral and microanalytical data. Moreover, the newly prepared compounds were subjected to molecular docking studies with DNA gyrase B and exhibited binding energy that extended from −9.8 to −6.4 kcal/mol, which confirmed their excellent potency. The compounds 6a,b were found to be with the minimum binding energy (−9.7 and −9.8 kcal/mol) as compared to the standard drug ciprofloxacin (−7.4 kcal/mol) against the target enzyme DNA gyrase B. In addition, the newly synthesized compounds were also examined and screened for their in vitro antimicrobial activity against pathogenic microorganisms Staphylococcus aureus, E. coli, Pseudomonas aeruginosa, Aspergillus niger, and Candida albicans. Among the newly synthesized molecules, significant antimicrobial activity against all the tested microorganisms was obtained for the compounds 6a,b. The in silico and in vitro findings showed that compounds 6a,b were the most active against bacterial strains, and could serve as potential antimicrobial agents.

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SYNTHESIS, CHARACTERIZATION AND BIOLOGICAL EVALUATION OF 3-FORMYL INDOLE BASED SCHIFF BASES

Journal of Biomedical and Pharmaceutical Research ◽

10.32553/jbpr.v7i6.561 ◽

2018 ◽

Vol 7 (6) ◽

Author(s):

Singh Gurvinder ◽

Singh Prabhsimran ◽

Dhawan R. K.

Keyword(s):

Antimicrobial Activity ◽

Spectral Analysis ◽

Schiff Bases ◽

Antimicrobial Agents ◽

Biological Evaluation ◽

Fungal Strain ◽

Bacterial Strains ◽

Standard Drug ◽

Gram Negative ◽

E Coli

In order to develop new antimicrobial agents, a series of 3-formyl indole based Schiff bases were synthesized by reacting 3-formyl indole(indole-3-carboxaldehyde) with substituted aniline taking ethanol as solvent. The reaction was carried in the presence of small amount of p-toluene sulphonic acid as catalyst.All the synthesized compounds were characterized by IR, 1H-NMR spectral analysis. All the synthesized compounds were evaluated for antimicrobial activity against two gram positive bacterial strains (B. subtilisand S. aureus) and two gram negative bacterial strains (P. aeruginosaand E. coli) and one fungal strain (C. albicans). All the synthesized compounds were found to have moderate to good antimicrobial activity. The standard drug amoxicillin, fluconazole were used for antimicrobial activity. Among the synthesized compounds, the maximum antimicrobial activity was shown by compounds GS04, GS07, GS08 and GS10.

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Synthesis of Novel 3(N,N-dialkylamino)alkyl/phenyl Substituted Thieno [2,3-d]pyrimidinones as H1-Anti-Histaminic and Antimicrobial Agents

Current Bioactive Compounds ◽

10.2174/1573407214666180226130957 ◽

2019 ◽

Vol 15 (1) ◽

pp. 63-70

Author(s):

Shiv Dev Singh ◽

Arvind Kumar ◽

Firoz Babar ◽

Neetu Sachan ◽

Arun Kumar Sharma

Keyword(s):

Antimicrobial Activity ◽

Potassium Hydroxide ◽

Antimicrobial Agents ◽

Pyrimidine Ring ◽

Antimicrobial Activities ◽

Screening Methods ◽

Chlorpheniramine Maleate ◽

In Vivo Screening

Background: Thienopyrimidines are the bioisoster of quinazoline and unlike quinazoline exist in three isomeric forms corresponding to the three possible types annulation of thiophene to the pyrimidine ring viz thieno[2,3-d] pyrimidine, thieno[3,2-d] pyrimidine and thieno[3,4-d]pyrimidine. Heterocyclic containing the thienopyrimidinone moiety exhibits various pronounced activities such as anti-hypertensive, analgesic and anti-inflammatory, antiviral, platelet aggregation inhibitory, antiprotozoal bronchodilatory, phosphodiesterase inhibitory, antihistaminic, antipsychotic and antimicrobial activity. Objective: Synthesis of novel 3(N,N-dialkylamino)alkyl/phenyl substituted thieno[2,3-d]pyrimidinones as H1-anti-histaminic and antimicrobial agents. Methods: A series of 3-[(N,N-dialkylamino)alkyl/phenyl]-2-(1H)thioxo-5,6,7,8-tetrahydrobenzo(b) thieno(2,3-d)pyrimidine-4(3H)-ones[4a-d], their oxo analogous [5a-d] and 3-[(N,N-dialkylamino)alkyl]- 2-chlorophenyl-5,6,7,8-tetrahydrobenzo(b)thieno(2,3-d)pyrimidine- 4 (3H)-ones[6a-d]derivative were synthesized from 2-amino-4,5,6,7-tetrahydrobenzo(b)thiophene-3-carboxylic acid by nucleophilic substitution of different N,N-dialkyl alkylene/phenylene diamines on activated 3-acylchloride moiety followed by cyclocondensation with carbon disulfide and ethanolic potassium hydroxide to get [4a-d] and in second reaction by condensation with 4-chlorobenzoyl chloride to get [6a-d] by single pot novel innovative route. The oxo analogous [5a-d] were prepared by treating derivatives [4a-d] with potassium permagnate in ethanolic KOH. The synthesized compound were evaluated for H1-antihistaminic and antimicrobial activities. Results: All synthesized compounds exhibited significant H1-antihistaminic activity by in vitro and in vivo screening methods and data were verified analytically and statistically. The compound 4a, 4b, 5a and 5b showed significant H1-antihistaminiic activity than the reference standard chlorpheniramine maleate. The compound 6d, 6c, 5c and 4c exhibited significant antimicrobial activity.

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An In Vitro Study on the Antimicrobial Properties of Essential Oil Modified Resin Composite against Oral Pathogens

Materials ◽

10.3390/ma13194383 ◽

2020 ◽

Vol 13 (19) ◽

pp. 4383

Author(s):

Barbara Lapinska ◽

Aleksandra Szram ◽

Beata Zarzycka ◽

Janina Grzegorczyk ◽

Louis Hardan ◽

...

Keyword(s):

Antimicrobial Activity ◽

Antibacterial Activity ◽

Antifungal Activity ◽

Antimicrobial Agents ◽

Resin Composite ◽

Antimicrobial Properties ◽

In Vitro Study ◽

Diffusion Method ◽

Oral Pathogens

Modifying the composition of dental restorative materials with antimicrobial agents might induce their antibacterial potential against cariogenic bacteria, e.g., S.mutans and L.acidophilus, as well as antifungal effect on C.albicans that are major oral pathogens. Essential oils (EOs) are widely known for antimicrobial activity and are successfully used in dental industry. The study aimed at evaluating antibacterial and antifungal activity of EOs and composite resin material (CR) modified with EO against oral pathogens. Ten EOs (i.e., anise, cinnamon, citronella, clove, geranium, lavender, limette, mint, rosemary thyme) were tested using agar diffusion method. Cinnamon and thyme EOs showed significantly highest antibacterial activity against S.mutans and L.acidophilus among all tested EOs. Anise and limette EOs showed no antibacterial activity against S.mutans. All tested EOs exhibited antifungal activity against C.albicans, whereas cinnamon EO showed significantly highest and limette EO significantly lowest activity. Next, 1, 2 or 5 µL of cinnamon EO was introduced into 2 g of CR and microbiologically tested. The modified CR showed higher antimicrobial activity in comparison to unmodified one. CR containing 2 µL of EO showed the best antimicrobial properties against S.mutans and C.albicans, while CR modified with 1 µL of EO showed the best antimicrobial properties against L.acidophilus.

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SYNTHESIS AND STRUCTURAL ELUCIDATION OF AMINO ACETYLENIC AND THIOCARBAMATES DERIVATIVES FOR 2-MERCAPTOBENZOTHIAZOLE AS ANTIMICROBIAL AGENTS

International Journal of Pharmacy and Pharmaceutical Sciences ◽

10.22159/ijpps.2017v9i2.15760 ◽

2017 ◽

Vol 9 (2) ◽

pp. 192

Author(s):

Aseel Alsarahni ◽

Zuhair Muhi Eldeen ◽

Elham Al-kaissi ◽

Ibrahim Al- Adham ◽

Najah Al-muhtaseb

Keyword(s):

Antimicrobial Activity ◽

Elemental Analysis ◽

Antimicrobial Agents ◽

Diffusion Method ◽

Benzothiazole Derivatives ◽

H Nmr ◽

Ft Ir ◽

Potential Antimicrobial Activity ◽

C Nmr

Objective: To design and synthesize amino acetylenic and thiocarbonate of 2-mercapto-1,3-benthiazoles as potential antimicrobial agents.Methods: A new series of 2-{[4-(t-amino-1-yl) but-2-yn-1-yl] sulfanyl}-1,3-benzothiazole derivatives (AZ1-AZ6), and S-1,3-benzothiazol-2-yl-O-alkyl carbonothioate derivatives were synthesised, with the aim that the target compounds show new and potential antimicrobial activity. The elemental analysis was indicated by the EuroEA elemental analyzer, and biological characterization was via IR, 1H-NMR, [13]C-NMR, DSC were determined with the aid of Bruker FT-IR and Varian 300 MHz spectrometer using DMSO-d6 as a solvent. In vitro antimicrobial activity, evaluation was done for the synthesised compounds, by agar diffusion method and broth dilution test. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) were determined. Results: The IR, 1H-NMR, 13C-NMR, DSC and elemental analysis were consistent with the assigned structures. Compound of 2-{[4-(4-methylpiperazin-1-yl)but-2-yn-1-yl] sulfanyl}-1,3-benzothiazole (AZ1), 2-{[4-(2-methylpiperidin-1-yl)but-2-yn-1-yl]sulfanyl}-1,3-benzothiazole (AZ2), 2-{[4-(piperidin-1-yl) but-2-yn-1-yl]sulfanyl}-1, 3-benzothiazole (AZ6), S-1,3-benzothiazol-2-yl-O-ethyl carbonothioate (AZ7), and S-1,3-benzothiazol-2-yl-O-(2-methylpropyl) carbonothioate (AZ9) showed the highest antimicrobial activity against Pseudomonas aeruginosa (P. aeruginosa), AZ-9 demonstrated the highest antifungal activity against Candida albicans (C. albicans), with MIC of 31.25 µg/ml.Conclusion: These promising results promoted our interest to investigate other structural analogues for their antimicrobial activity further.

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In Vitro Antimicrobial Activity of the Decontaminant HybenX® Compared to Chlorhexidine and Sodium Hypochlorite against Common Bacterial and Yeast Pathogens

Antibiotics ◽

10.3390/antibiotics8040188 ◽

2019 ◽

Vol 8 (4) ◽

pp. 188 ◽

Cited By ~ 3

Author(s):

Alberto Antonelli ◽

Luca Giovannini ◽

Ilaria Baccani ◽

Valentina Giuliani ◽

Riccardo Pace ◽

...

Keyword(s):

Antimicrobial Activity ◽

Sodium Hypochlorite ◽

Fungal Pathogens ◽

Antimicrobial Agents ◽

Fungal Infections ◽

Yeast Strains ◽

Low Concentrations ◽

Endodontic Infections ◽

Reference Strains

The recent increase in infections mediated by drug-resistant bacterial and fungal pathogens underlines the urgent need for novel antimicrobial compounds. In this study, the antimicrobial activity (inhibitory and cidal) of HybenX®, a novel dessicating agent, in comparison with commonly used sodium hypochlorite and chlorhexidine, against a collection of bacterial and yeast strains representative of the most common human pathogenic species was evaluated. The minimal inhibitory, bactericidal, and fungicidal concentrations (MIC, MBC, and MFC, respectively) of the three different antimicrobial agents were evaluated by broth microdilution assays, followed by subculturing of suitable dilutions. HybenX® was active against 26 reference strains representative of staphylococci, enterococci, Enterobacterales, Gram-negative nonfermenters, and yeasts, although at higher concentrations than sodium hypochlorite and chlorhexidine. HybenX® MICs were 0.39% for bacteria (with MBCs ranging between 0.39% and 0.78%), and 0.1–0.78% for yeasts (with MFCs ranging between 0.78% and 1.6%). HybenX® exhibited potent inhibitory and cidal activity at low concentrations against several bacterial and yeast pathogens. These findings suggest that HybenX® could be of interest for the treatment of parodontal and endodontic infections and also for bacterial and fungal infections of other mucous membranes and skin as an alternative to sodium hypochlorite and chlorhexidine.

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SPS-neutralization in tissue samples for efficacy testing of antimicrobial peptides

BMC Infectious Diseases ◽

10.1186/s12879-019-4700-1 ◽

2019 ◽

Vol 19 (1) ◽

Author(s):

Gabrielle Sherella Dijksteel ◽

Peter H. Nibbering ◽

Magda M. W. Ulrich ◽

Esther Middelkoop ◽

Bouke K. H. L. Boekema

Keyword(s):

Antimicrobial Activity ◽

Antimicrobial Peptides ◽

Antimicrobial Agents ◽

Ex Vivo ◽

Residual Activity ◽

Gram Negative Bacteria ◽

Tissue Samples ◽

Gram Negative ◽

Viable Bacteria

Abstract Background Accurate determination of the efficacy of antimicrobial agents requires neutralization of residual antimicrobial activity in the samples before microbiological assessment of the number of surviving bacteria. Sodium polyanethol sulfonate (SPS) is a known neutralizer for the antimicrobial activity of aminoglycosides and polymyxins. In this study, we evaluated the ability of SPS to neutralize residual antimicrobial activity of antimicrobial peptides [SAAP-148 and pexiganan; 1% (wt/v) in PBS], antibiotics [mupirocin (Bactroban) and fusidic acid (Fucidin) in ointments; 2% (wt/wt))] and disinfectants [2% (wt/wt) silver sulfadiazine cream (SSD) and 0.5% (v/v) chlorhexidine in 70% alcohol]. Methods Homogenates of human skin models that had been exposed to various antimicrobial agents for 1 h were pipetted on top of Methicillin-resistant Staphylococcus aureus (MRSA) on agar plates to determine whether the antimicrobial agents display residual activity. To determine the optimal concentration of SPS for neutralization, antimicrobial agents were mixed with PBS or increasing doses of SPS in PBS (0.05–1% wt/v) and then 105 colony forming units (CFU)/mL MRSA were added. After 30 min incubation, the number of viable bacteria was assessed. Next, the in vitro efficacy of SAAP-148 against various gram-positive and gram-negative bacteria was determined using PBS or 0.05% (wt/v) SPS immediately after 30 min incubation of the mixture. Additionally, ex vivo excision wound models were inoculated with 105 CFU MRSA for 1 h and exposed to SAAP-148, pexiganan, chlorhexidine or PBS for 1 h. Subsequently, samples were homogenized in PBS or 0.05% (wt/v) SPS and the number of viable bacteria was assessed. Results All tested antimicrobials displayed residual activity in tissue samples, resulting in a lower recovery of surviving bacteria on agar. SPS concentrations at ≥0.05% (wt/v) were able to neutralize the antimicrobial activity of SAAP-148, pexiganan and chlorhexidine, but not of SSD, Bactroban and Fucidin. Finally, SPS-neutralization in in vitro and ex vivo efficacy tests of SAAP-148, pexiganan and chlorhexidine against gram-positive and gram-negative bacteria resulted in significantly higher numbers of CFU compared to control samples without SPS-neutralization. Conclusions SPS was successfully used to neutralize residual activity of SAAP-148, pexiganan and chlorhexidine and this prevented an overestimation of their efficacy.

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Synthesis, Antimicrobial Activity and Molecular Docking of Novel Thiourea Derivatives Tagged with Thiadiazole, Imidazole and Triazine Moieties as Potential DNA Gyrase and Topoisomerase IV Inhibitors

Molecules ◽

10.3390/molecules25122766 ◽

2020 ◽

Vol 25 (12) ◽

pp. 2766 ◽

Cited By ~ 1

Author(s):

Heba E. Hashem ◽

Abd El-Galil E. Amr ◽

Eman S. Nossier ◽

Elsayed A. Elsayed ◽

Eman M. Azmy

Keyword(s):

Antimicrobial Activity ◽

Molecular Docking ◽

Antimicrobial Agents ◽

Biological Activities ◽

Topoisomerase Iv ◽

Thiourea Derivatives ◽

E Coli ◽

Cytotoxicity Studies ◽

Ic50 Values

To develop new antimicrobial agents, a series of novel thiourea derivatives incorporated with different moieties 2–13 was designed and synthesized and their biological activities were evaluated. Compounds 7a, 7b and 8 exhibited excellent antimicrobial activity against all Gram-positive and Gram-negative bacteria, and the fungal Aspergillus flavus with minimum inhibitory concentration (MIC) values ranged from 0.95 ± 0.22 to 3.25 ± 1.00 μg/mL. Furthermore, cytotoxicity studies against MCF-7 cells revealed that compounds 7a and 7b were the most potent with IC50 values of 10.17 ± 0.65 and 11.59 ± 0.59 μM, respectively. On the other hand, the tested compounds were less toxic against normal kidney epithelial cell lines (Vero cells). The in vitro enzyme inhibition assay of 8 displayed excellent inhibitory activity against Escherichia coli DNA B gyrase and moderate one against E. coli Topoisomerase IV (IC50 = 0.33 ± 1.25 and 19.72 ± 1.00 µM, respectively) in comparison with novobiocin (IC50 values 0.28 ± 1.45 and 10.65 ± 1.02 µM, respectively). Finally, the molecular docking was done to position compound 8 into the E. coli DNA B and Topoisomerase IV active pockets to explore the probable binding conformation. In summary, compound 8 may serve as a potential dual E. coli DNA B and Topoisomerase IV inhibitor.

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