scholarly journals Sulfonyl thiosemicarbazones: synthesis, characterization and antibacterial activity

Author(s):  
Priyanka Yadav ◽  
Praveen Kumar ◽  
Ayaz Mahmood Dar

The reaction of sulfonyl ketones (1-3) with thiosemicarbazide under reflux conditions yielded the sulfonyl thiosemicarbazones (4-6) in good to potential amounts (72-80%). The structure of new compounds (4-6) was confirmed by different spectral (IR, 1H NMR, 13C NMR, MS) and analytical techniques. The investigation of antibacterial screening data revealed that all the tested compounds (4-6) exhibited moderate to decent antibacterial activity against S. pyogenes, S. aureus and E. coli strains. The compounds 4-6 depicted zones of inhibition, i.e., 20.3 mm, 21.2 mm and 19.6 mm against S. pyogenes strain, respectively.

2009 ◽  
Vol 74 (10) ◽  
pp. 1041-1049 ◽  
Author(s):  
Stefania Barbuceanu ◽  
Gabriela Almajan ◽  
Ioana Saramet ◽  
Constantin Draghici ◽  
Radu Socoteanu ◽  
...  

Alkylation of the 5-{4-[(4-bromophenyl)sulfonyl]phenyl}-4-(3/4-methylphenyl)- 2,4-dihydro-3H-1,2,4-triazole-3-thiones 3a,b with various alkylation agents, i.e., ethyl bromide, phenacyl bromide and ethyl chloroacetate, afforded the S-substituted 1,2,4-triazoles 4-6a,b. The structures of these new compounds were elucidated by elemental analysis and IR, UV, 1H-NMR, 13C-NMR and MS spectroscopy. The newly synthesized products were tested for their antibacterial effects.


2016 ◽  
Vol 5 (04) ◽  
pp. 4512
Author(s):  
Jackie K. Obey ◽  
Anthoney Swamy T* ◽  
Lasiti Timothy ◽  
Makani Rachel

The determination of the antibacterial activity (zone of inhibition) and minimum inhibitory concentration of medicinal plants a crucial step in drug development. In this study, the antibacterial activity and minimum inhibitory concentration of the ethanol extract of Myrsine africana were determined for Escherichia coli, Bacillus cereus, Staphylococcus epidermidis and Streptococcus pneumoniae. The zones of inhibition (mm±S.E) of 500mg/ml of M. africana ethanol extract were 22.00± 0.00 for E. coli,20.33 ±0.33 for B. cereus,25.00± 0.00 for S. epidermidis and 18. 17±0.17 for S. pneumoniae. The minimum inhibitory concentration(MIC) is the minimum dose required to inhibit growth a microorganism. Upon further double dilution of the 500mg/ml of M. africana extract, MIC was obtained for each organism. The MIC for E. coli, B. cereus, S. epidermidis and S. pneumoniae were 7.81mg/ml, 7.81mg/ml, 15.63mg/ml and 15.63mg/ml respectively. Crude extracts are considered active when they inhibit microorganisms with zones of inhibition of 8mm and above. Therefore, this study has shown that the ethanol extract of M. africana can control the growth of the four organisms tested.


2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Pablo E. Romo ◽  
Braulio Insuasty ◽  
Rodrigo Abonia ◽  
María del Pilar Crespo ◽  
Jairo Quiroga

A versatile method for the synthesis of new oxindoles was developed by the reaction between substituted isatins and 5-aminopyrazoles. The reaction was carried out at room temperature in ethanol using p-toluenesulfonic acid as the catalyst. The products were obtained with acceptable to excellent yields (44–96%). Structures of the new compounds were unambiguously established by spectroscopic and analytical techniques. The antibacterial activity was determined by microdilution assays. Compounds 3b, 3e, and 3g showed antistaphylococcal activity, particularly compound 3e displayed a potent activity against the vancomycin intermediate Staphylococcus aureus (VISA). Compounds 3i, 3j, and 3o inhibited Neisseria gonorrhoeae growth.


2021 ◽  
pp. e304
Author(s):  
Candy GERGES ◽  
Mohamad HADLA ◽  
Michele ELIALI ◽  
Martine RICHA ◽  
Nour Mammari ◽  
...  

Background: Thousands of people are dying as a result of infections caused by bacteria. Among the main routes of germ transmission are the hands, making hand hygiene very important in preventing the spread of pathogens and bacterial infection. Hand washing with soap and water is considered to be a simple and effective measure. Old soap manufacturers have long had traditional uses in the Lebanese community. Methods: The purpose of this study is to compare the antibacterial activity of oil-based soaps with commercial soap sold in the Lebanese market. Different types of herbal soap and antiseptics have been used in this study. Four bacterial strains were used: Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Escherichia coli and Enterobacter Spp. The antibacterial activities of these soaps were determined by the diffusion method of disks in agar medium. Results and Discussion: Statistical analysis of zones of inhibition showed that S. epidermidis, P. aeruginosa and Enterobacter Spp. were sensitive only to traditional oil-based soaps, which are Sage, Rose Mary and Cedar. In addition, S. aureus showed sensitivity to soaps comprised of essential oils as well as antibacterial synthetic soap, Dettol and Lifebuoy. On the other hand, E. coli showed resistance to all soaps. Soaps comprised of natural essential oils have shown antibacterial activity superior to so-called “Antibacterial” soaps. Conclusion: Based on this study, we can say that the use of soaps with essential oils might be the best option due to their organic origin as well as their antibacterial proved activities.


2020 ◽  
Vol 63 (9) ◽  
pp. 31-34
Author(s):  
Natalia V. Nosova ◽  
◽  
Daria D. Lezhnina ◽  
Daria D. Rubtsova ◽  
Vladimir L. Gein ◽  
...  

Functionalized cyclohexanones are multifunctional highly reactive available substrates. They are convenient for the synthesis of new compounds, including practically significant ones. The presence of a 1,3-dicarbonyl fragment in their composition makes it possible to obtain various heterocyclic systems in reactions with binucleophilic reagents: indazoles, benzisoxazoles, and diazepines. The interaction of cyclohexanones functionalized with acetyl or alkoxycarbonyl substituents with hydroxylamine was previously studied. It was shown that, depending on the nature of the substituents, the reaction can proceed with the formation of the corresponding oximes, or give products of heterocyclization – benzisoxazoles. The interaction of cyclohexanones containing amide groups in an alicycle with hydroxylamine has not been studied. We studied the reaction of unsubstituted 2-aryl-4-hydroxy-4-methyl-6-oxocyclohexane-1,3-dicarboxamides with hydroxylamine hydrochloride in the presence of an equivalent amount of alkali. When boiling in ethanol in the absence of a catalyst, new 2-aryl-4-hydroxy-6-(hydroxyimino)-4-methylcyclohexane-1,3-dicarboxamides were obtained. Cyclization with the formation of benzisoxazoles does not occur in this case due to a lower positive charge on the carbon atom of the amide group compared to the carbon atom of the acetyl or alkoxycarbonyl groups. The structure of the synthesized compounds was established based on the data of IR, 1H NMR and 13C NMR spectroscopy. The IR spectra of the obtained oximes contain bands of valence vibrations of the OH, NH, and CON groups. The 1H NMR spectra contain four NH-proton singlets of two amide groups, the proton singlet =N-OH group. The 13C NMR spectra of solutions of compounds contain signals of two carbon atoms of amide groups and a carbon atom of the C=N-OH group, which fully confirm the assumed structure.


Author(s):  
S. A. Wemedo ◽  
N. P. Akani ◽  
A. D. Amadiali

Aim: The antibacterial activity of Bay leaf (Laurus nobilis L.) and Zobo leaf (Hibiscus sabdariffa L.) extracts on enteropathogenic bacteria was investigated. Study Design: The study utilized well in agar diffusion to investigate the antimicrobial properties of the extracts. Place and Duration of Study: Department of Microbiology, Rivers State University and the study was carried out in August, 2018 to October, 2018. Methodology: Faecal samples were collected from a medical laboratory and inoculated on eosin methylene blue and mannitol salt agar plates for Escherichia coli and Staphylococcus aureus using standard microbiological techniques. The bacterial isolates were subjected to biochemical and molecular (PCR) identification so as to ascertain the distinctiveness of the isolates. Hot water and absolute alcohol were used as the extracting solvents. Concentrations of the extracted solvents was tested against E. coli and S. aureus using the well in agar method. Results: The result showed that both hot aqueous and alcoholic extracts of Bay leaf showed no sensitivity against the tested bacteria, whereas the extracts of hot dry aqueous and alcohol of Zobo leaf showed remarkable zones of inhibition against the tested bacteria. The zones of inhibition in the dry hot aqueous extract of zobo leaf with concentrations of 0.25 µg/mL, 0.125 µg/mL and 0.063 µg/mL were 31.3±0.1, 25.6±1.2 and 10.0±0.0, respectively. The minimal inhibitory concentration of the dry hot aqueous of zobo extract was observed at 0.063 µg/mL for E. coli, while zones of inhibition of 33.3±0.0, 30.1±0.3, 17.2±1.0 and 15.0±0.1 mm were recorded from the dry alcoholic extract of zobo leaf on E. coli given similar concentrations and the MIC was observed at the 0.031 µg/mL concentration. The result also showed that out of the four concentrations of the dry hot aqueous extract, only the 0.25 µg/mL concentration was able to show 14.2±0.0 mm inhibition on S. aureus, while the concentrations of 0.25 µg/ml and 0.125 µg/mL were the only two concentrations of the dry alcohol that showed levels of sensitivity with zone diameters of 29.3±1.0 and 25.2±0.0, respectively. Conclusion: The plant extracts of zobo leaves which displayed remarkable activity at fairly-low concentrations could be recommended for use against similar bacteria. Thus, investigation and adoption of plant extracts in modern medicine should be encouraged as this may be the break through needed to combat the ever-increasing resistance to commonly used antibiotics.


2017 ◽  
Vol 68 (11) ◽  
pp. 2503-2508 ◽  
Author(s):  
Laura Ileana Socea ◽  
Stefania Felicia Barbuceanu ◽  
Bogdan Socea ◽  
Constantin Draghici ◽  
Theodora Venera Apostol ◽  
...  

Acylhydrazinecarbothioamides (2a,b) were synthesized by addition of 2-(5H-dibenzo[a,d][7]annulen-5-yl)acetohydrazide to different isothiocyanates. The new 1,2,4-triazol-3-thioles (3a,b) were synthesized by cyclization of new 2- acylhydrazinecarbothioamides (3a,b) in basic media. Alkylation of 1,2,4-triazole-3-thiols (3a-c) with ethyl bromide gave only S-substituted derivatives (4a-c). The structures of the synthesized compounds have been established on spectral data (IR, 1H-NMR and 13C-NMR spectroscopy) and elemental analysis. The cytotoxic effect of new compounds was evaluated using two alternative models on plant and invertebrate organisms.


2021 ◽  
Vol 14 (5) ◽  
pp. 399
Author(s):  
Lamya H. Al-Wahaibi ◽  
Amer A. Amer ◽  
Adel A. Marzouk ◽  
Hesham A.M. Gomaa ◽  
Bahaa G. M. Youssif ◽  
...  

A novel series of ciprofloxacin hybrids comprising various heterocycle derivatives has been synthesized and structurally elucidated using 1H NMR, 13C NMR, and elementary analyses. Using ciprofloxacin as a reference, compounds 1–21 were screened in vitro against Gram-positive bacterial strains such as Staphylococcus aureus and Bacillus subtilis and Gram-negative strains such as Escherichia coli and Pseudomonas aeruginosa. As a result, many of the compounds examined had antibacterial activity equivalent to ciprofloxacin against test bacteria. Compounds 2–6, oxadiazole derivatives, were found to have antibacterial activity that was 88 to 120% that of ciprofloxacin against Gram-positive and Gram-negative bacteria. The findings showed that none of the compounds tested had antifungal activity against Aspergillus flavus, but did have poor activity against Candida albicans, ranging from 23% to 33% of fluconazole, with compound 3 being the most active (33% of fluconazole). The most potent compounds, 3, 4, 5, and 6, displayed an IC50 of 86, 42, 92, and 180 nM against E. coli DNA gyrase, respectively (novobiocin, IC50 = 170 nM). Compounds 4, 5, and 6 showed IC50 values (1.47, 6.80, and 8.92 µM, respectively) against E. coli topo IV in comparison to novobiocin (IC50 = 11 µM).


2019 ◽  
Vol 62 (2) ◽  
pp. 97-100
Author(s):  
Taif Shah ◽  
Niyaz Ali ◽  
Zahir Shah ◽  
Azam Hayat

The current study was conducted to determine the antibacterial activity of 50 crude and processed honey samples produced by Apis mellifera and stingless bee. All the honey samples were collected from different places of Districts Dir, Swat and Oghi of Khyber Pakhtunkhwa Province, Pakistan and were tested against the six ATCC bacterial species including E. coli ATCC number 25922, Pseudomonas aeruginosa ATCC number 27853, Staphylococcus aureus ATCC number 6538, Enterococcus faecalis ATCC number 19433, Salmonella typhi ATCC number 19943 and Klebsiella pneumoniae ATCC number 27736. The honey samples showed variable zones of inhibition by using Agar well plate technique. E. coli showed 17-23 mm, S. typhi 31-37 mm, E. faecalis 28 mm, P. aeruginosa 14-15 mm, K. pneumoniae 20-24 mm and Staph. aureus 19-25 mm. Most of the honey samples used in this study showed broad spectrum antibacterial activity.


2014 ◽  
Vol 14 (1) ◽  
pp. 32-36 ◽  
Author(s):  
Hartiwi Diastuti ◽  
Yana Maolana Syah ◽  
Lia Dewi Juliawaty ◽  
Marlia Singgih

The isolation of terpenoids from C. heyneana rhizomes and their antibacterial activity have been conducted. The terpenoids were isolated by using vacuum liquid chromatography and radial chromatography. The structures of the compounds were determined based on spectroscopic data (1H-NMR, 13C-NMR (1D and 2D)). The antibacterial activity was carried out by using microdilution method and evaluated against eight bacteria. Three germacrane type sesquiterpenes have been isolated from C. heyneana rhizhomes and were identified as germacrone, dehydrocurdione, and 1(10),4(5)-diepoxygermacrone. Germacrone showed highest antibacterial activity against P. aeruginosa with MIC values of 15.6 µg/mL and MBC values 31.2 µg/mL. Dehydrocurdione showed highest antibacterial activity against B. subtilis with MIC values of 31.2 µg/mL and MBC values of 31.2 µg/mL. However, 1(10),4(5)-diepoxygermacrone showed a weak antibacterial activity.


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