scholarly journals Synthesis of sulfonamides bearing 1,3,5-triarylpyrazoline and 4-thiazolidinone moieties as novel antimicrobial agents

2020 ◽  
Vol 85 (2) ◽  
pp. 155-162
Author(s):  
Thi-Dan Thach ◽  
Thi Le ◽  
Thien-Annguyen Nguyen ◽  
Chi-Hien Dang ◽  
Van-Su Dang ◽  
...  

Two series of sulfonamides were synthesized from 4-hydrazinylbenzenesulfonamide as the key starting material. 1,3,5-Triarylpyrazoline sulfonamides (2a?i) were obtained by cyclocondensation of various chalcones in 53? ?64 % yields, while 4-thiazolidinone derivatives (4a?e) were synthesized by cyclocondensation between mercaptoacetic acid and different phenylhydrazones in 43?62 % yields. The synthesized compounds were characterized based on FTIR, 1H-NMR, 13C-NMR and HRMS data. The sulfonamides were evaluated for their in vitro antimicrobial activities against four bacterial strains (E. coli, P. aeruginosa, B. subtillis and S aureus), two filamentous fungal strains (A. niger and F. oxysporum) and two yeast strains (C. albicans and S. cerevisiae). Seven pyrazolines, 2a?c and 2e?h, exhibited significant inhibition of different microbial strains. Among them, compound 2b displayed good antifungal activity against A. niger (MIC value at 12.5 ?g mL-1) over the reference drug.

2014 ◽  
Vol 79 (2) ◽  
pp. 115-123 ◽  
Author(s):  
Anca Stana ◽  
Brînduşa Tiperciuc ◽  
Mihaela Duma ◽  
Adrian Pîrnău ◽  
Philippe Verité ◽  
...  

A series of new 5-(2,6-dichlorobenzylidene)thiazolidine-2,4-dione and 5-(4-methoxy-benzylidene)thiazolidine-2,4-dione derivatives (3a-h and 5a-h) were synthesized starting from 5-arylidene-thiazolidine-2,4-dione and ?-halo-ketones. The structural elucidation of the newly synthesized compounds was based on elemental analysis and spectroscopic data (MS, 1H-NMR, 13C-NMR). The synthesized compounds were screened for their antimicrobial activities against several pathogenic strains of Gram-positive and Gram-negative bacteria and one fungal strain (Candida albicans), assessed in vitro as growth inhibition diameters. Some of them displayed better inhibitory activities than that of the reference drug against the Gram-positive S. aureus, B. cereus, L. monocytogenes bacterial strains, and showed good antifungal activity against C. albicans, while the antibacterial activity against Gram-negative E. coli and S. typhimurium bacterial strains was moderate.


2019 ◽  
Author(s):  
Chem Int

New copper complexes, [Cu(phen)2(Thy)]2Cl and [Cu(phen)2(Ad)]2Cl (phen = 1,10-phenantroline, Ad (Adenine, a purine nucleobase) and Thy (Thymine, a pyrimidine nucleobase)), were synthesized and characterized by atomic absorption spectroscopy (AAS), conductivity measurement, UV-visible and infrared (IR) techniques. The complexes were tested for their antimicrobial activity against two gram positive and two gram negative bacterial strains. The results of in vitro antimicrobial activities were compared with the commercially available antimicrobial agents (ciprofloxacin and chloramphenicol). This comparative study has demonstrated that [Cu(phen)2(Thy)]2Cl inhibited the growth of methicillin resistant Staphylococcus aureous (MRSA), Escherichia coli (E. coli) and Klebsiella pneumoniae (K. pneumonia) better than chloramphenicol by 11.25%, 19.41% and 25.35%, respectively. It also showed better activities than ciprofloxacine on MRSA and K. pneumoniae by 2.50% and 12.13%, respectively. Similarly, [Cu(phen)2(Ad)]2Cl demonstrated better inhibitions than chloramphenicol against MRSA, E. coli and K. pneumoniae by 11.24%, 2.48% and 9.06%, respectively. Therefore, after in vivo cytotoxicity investigations, these complexes could be considered as potential antimicrobial agents.


2020 ◽  
Vol 11 ◽  
pp. 37-43
Author(s):  
Prof. Teodora P. Popova ◽  
Toshka Petrova ◽  
Ignat Ignatov ◽  
Stoil Karadzhov

The antimicrobial action of the dietary supplement Oxidal® was tested using the classic Bauer and Kirby agar-gel diffusion method. Clinical and reference strains of Staphylococcus aureus and Escherichia coli were used in the studies. The tested dietary supplement showed a well-pronounced inhibitory effect against the microbial strains commensurable with that of the broad-spectrum chemotherapeutic agent Enrofloxacin and showed even higher activity than the broad spectrum antibiotic Thiamphenicol. The proven inhibitory effect of the tested dietary supplement against the examined pathogenic bacteria is in accordance with the established clinical effectiveness standards for antimicrobial agents.


2020 ◽  
Vol 2020 ◽  
pp. 1-9 ◽  
Author(s):  
Phan-Canh Trinh ◽  
Le-Thi-Thanh Thao ◽  
Hoang-Tran-Viet Ha ◽  
TuAnh Nguyen

Asteraceae species were widely applied in traditional medicines in Asian countries as sources of natural antioxidants and antimicrobial agents. This study aimed to evaluate DPPH-scavenging capacities and antimicrobial activities of nine Asteraceae species collected from Southern Vietnam. Antioxidant and antimicrobial activities were determined by standard protocols. Essential oils from Ageratum conyzoides, Helianthus annuus, and Artemisia vulgaris indicated significant inhibitory effects on Staphylococcus aureus and Candida spp. Crude extracts and fractions from Taraxacum officinale, Chrysanthemum morifolium, A. conyzoides, and Tagetes erecta showed inhibitory ability on at least one testing bacterial strains including S. aureus, Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa. In a study on clinical isolates, ethyl acetate fraction from A. conyzoides flower displayed the most potent effect on uropathogenic E. coli and K. pneumoniae with MIC at 1.25–10 mg/ml and 5–12.5 mg/ml, respectively. DPPH-scavenging assay indicated that T. erecta extract had the lowest IC50 (17.280 μg/ml) and is 2.4 times higher than vitamin C (7.321 μg/ml). This study revealed that A. conyzoides has good potential against uropathogenic E. coli and K. pneumoniae, and therefore could be applied for prophylactic treatment of urinary infection.


2020 ◽  
Vol 13 (12) ◽  
pp. 469
Author(s):  
Sergey N. Lavrenov ◽  
Elena B. Isakova ◽  
Alexey A. Panov ◽  
Alexander Y. Simonov ◽  
Viktor V. Tatarskiy ◽  
...  

The wide spread of pathogens resistance requires the development of new antimicrobial agents capable of overcoming drug resistance. The main objective of the study is to elucidate the effect of substitutions in tris(1H-indol-3-yl)methylium derivatives on their antibacterial activity and toxicity to human cells. A series of new compounds were synthesized and tested. Their antibacterial activity in vitro was performed on 12 bacterial strains, including drug resistant strains, that were clinical isolates or collection strains. The cytotoxic effect of the compounds was determined using an test with HPF-hTERT (human postnatal fibroblasts, immortalized with hTERT) cells. The activity of the obtained compounds depended on the carbon chain length. Derivatives with C5–C6 chains were more active. The minimum inhibitory concentration (MIC) of the most active compound on Gram-positive bacteria, including MRSA, was 0.5 μg/mL. Compounds with C5–C6 chains also revealed high activity against Staphylococcus epidermidis (1.0 and 0.5 μg/mL, respectively) and moderate activity against Gram-negative bacteria Escherichia coli (8 μg/mL) and Klebsiella pneumonia (2 and 8 μg/mL, respectively). However, they have no activity against Salmonella cholerasuis and Pseudomonas aeruginosa. The most active compounds revealed higher antibacterial activity on MRSA than the reference drug levofloxacin, and their ratio between antibacterial and cytotoxic activity exceeded 10 times. The data obtained provide a basis for further study of this promising group of substances.


2013 ◽  
Vol 2013 ◽  
pp. 1-12 ◽  
Author(s):  
Reena Jain ◽  
Rajeev Singh ◽  
N. K. Kaushik

A new series of organotin(IV) complexes with purine bases theophylline (HL1) and theobromine (L2) of the types R3Sn(L1), R2Sn(L1)Cl, R3Sn(L2)Cl, and R2Sn(L2)Cl2(R = C6H5CH2–;p-ClC6H4CH2–) have been synthesized in anhydrous THF. The complexes were characterized by elemental analysis, conductance measurements, molecular weight determinations, UV-vis, IR,1H,13C NMR, and mass spectral studies. Various kinetic and thermodynamic parameters of these complexes have also been determined using TG/DTA technique. The thermal decomposition techniques indicate the formation of SnO2as a residue. The results show that the ligands act as bidentate, forming a five-member chelate ring. All the complexes are 1 : 1 metal-ligand complexes. In order to assess their antimicrobial activity, the ligands and their corresponding complexes have also been testedin vitroagainst bacteria (E. coli, S. aureus, andP. pyocyanea) and fungi (Rhizopus oryzaeandAspergillus flavus). All the complexes exhibit remarkable activity, and the results provide evidence that the studied complexes might indeed be a potential source of antimicrobial agents.


2021 ◽  
Vol 33 (7) ◽  
pp. 1525-1529
Author(s):  
Parmesh Kumar Dwivedi ◽  
Devdutt Chaturvedi

A new series of fluorinated sulfur inserted benzimidazole analogues Za-i were synthesized and characterized. The new compounds were screened for their antimicrobial and antioxidant potential. The synthesized compounds were obtained by multiple step synthesis, initiating from the synthesis of 5-(difluoromethoxy)-1H-benzimidazole-2-thiol X. The compounds Ya-i prepared by reacting differently substituted anilines with chloroacetylchloride and triethylamine in DMF. Finally, the compound X was reacted with different derivatives of 2-chloro-N-phenylacetamide resulting in formation of titled compounds Za-i. The synthesized compounds (Za-Zi) were characterized by spectral analysis viz.1H & 13C NMR, mass spectra, elemental analysis and IR. The in vitro antimicrobial potential against Gram-positive (S. aureus and E. faecalis) and Gram-negative bacterial (E. coli and P.aeruginosa) strains as well as fungi (A. niger and C. albicans) was recorded for the obtained compounds. Some of the compounds exhibited encouraging results (in MIC) against Gram-positive and Gram-negative bacterial strains. These studies thus suggest that the designed sulfur inserted fluoro-benzimidazoles scaffold may serve as new promising template for further amplification as antimicrobial agents.


2007 ◽  
Vol 2 (11) ◽  
pp. 1934578X0700201 ◽  
Author(s):  
Katalin Veres ◽  
Erzsébet Varga ◽  
Zsuzsanna Schelz ◽  
József Molnár ◽  
Jenő Bernáth ◽  
...  

The essential oils of four lines of Origanum vulgare L. subsp. hirtum (Link) Ietswaart cultivated in Hungary were analysed by GC and GC-MS methods. These oils were found to contain carvacrol, γ-terpinene and p-cymene as main constituents. The antimicrobial activities of the various oils and their authentic individual components were tested on Gram-positive and Gram-negative bacterial strains, two Saccharomyces cerevisiae strains and two Candida albicans strains. No difference in sensitivity was found between Escherichia coli, Staphylococcus epidermidis and the yeast strains tested, but there were marked differences in sensitivity between the proton pump-deficient mutant of E. coli and its wild type as regards the growth inhibition and MIC values.


2016 ◽  
Vol 29 (1) ◽  
pp. 37-40
Author(s):  
Amna Ali ◽  
M Saleem Haider ◽  
Sobia Mushtaq ◽  
Ibatsam Khokhar ◽  
Irum Mukhtar ◽  
...  

The antimicrobial agents of bacteria isolated from different rhizosphere of fruits and vegetables soil in Lahore. Of ten species, five were gram-negative (Escherichia coli, Pseudomonas fluorescence, Klebsiella pneumoniae, Salmonella typhii, Brachybacterium faecium); other five were gram positive and identified as Bacillus farraginis, Kurthia gibsonii, Aureobacterium liquefaciens, Curtobacterium albidum, Micrococcus lylae. The antagonistic potential of bacterial strains was assessed by the well diffusion technique and results indicating varying degree of biocontrol activity against pathogenic strain of X. campestris. Out of ten bacterial species, E. coli (gram negative) and C. albidum (gram positive) showed a high prevalence of resistance with reduction of 4.2cm and 4.1cm zone diameter respectively. The minimum inhibitory volume (MIV) to two bio-agents was determined for X. campestris from range 10-100 ?L. E. coli (volume required to inhibit < 20 ?L) and C. albidum (volume required to inhibit < 40 ?L) exhibited good activity against pathogen. These results provide information on the prevalence of resistant bacterial strains with the MIV of organisms and indicate the possibility of using these bacterial species as bio-agent against X. campestris.Bangladesh J Microbiol, Volume 29, Number 1, June 2012, pp 37-40


2021 ◽  
Vol 2021 ◽  
pp. 1-5
Author(s):  
Asnakew Amare Tadesse ◽  
Negera Abdissa Ayana ◽  
Dele Abdissa Keneni

Sequential extraction using a cold maceration method and column chromatographic separation of the roots Kniphofia insignis headed to the isolation of three anthraquinones: one monomeric anthraquinone (1) and two dimeric anthraquinones (2 and 3). It was further purified by Sephadex LH-20 and recrystallized. The structures of these compounds were established based on the spectroscopic analyses including NMR (1H-NMR and 13C-NMR and infrared) and comparison with reported literatures. In an in vitro antimicrobial assay of the crude extracts, the isolated compounds were made against four bacterial strains (S. aureus ATCC 25923, B. subtilis ATCC 6633, E. coli ATCC 35218, and P. aeruginosa ATCC 27853) and Fusarium spp. fungal strain. In the crude extracts of chloroform, substantial antimicrobial activity was seen with the highest activity against B. subtilis (16 mm) and E. coli (22 mm). Meanwhile, compound 1 has a better zone of inhibition with 14 mm against P. aeruginosa, whereas compound 2 showed better activity (13 mm) against Fusarium spp. fungal strain.


Sign in / Sign up

Export Citation Format

Share Document