Design, Synthesis and Evaluation of Thiourea Derivatives as Antimicrobial and Antiviral Agents

2019 ◽  
Vol 16 (6) ◽  
pp. 618-624 ◽  
Author(s):  
Veerasamy Ravichandran ◽  
Sivadasan Shalini ◽  
Krishnan Suresh Kumar ◽  
Harish Rajak ◽  
Ram Kishore Agrawal

Background: The development of drug-resistant by bacteria appears rapidly and thus making the effectiveness of antibiotics severely limited. Methods: A series of thiourea derivatives was synthesized, characterized and evaluated for their in vitro antibacterial, antifungal and antiviral activities. Results: Structures of the newly synthesized compounds were confirmed by elemental and spectral analysis. The biological results showed that some of the target compounds displayed comparable antimicrobial and antiviral activities with reference drugs. Structure-activity relationship studies revealed that the ortho- chloro or fluoro substituted phenyl at Ar1 and substituted pyridinyl at Ar2 positions of the thiourea nucleus are essential for their in vitro antimicrobial and anti-HIV activity. In particular, compounds 8 and 10 showed better activity against the tested bacteria, fungi and viral strains than other synthesized PET derivatives reported in the present study. Conclusion: These results provide an encouraging lead that could be used for the development of new potent antiviral and antimicrobial agents

2021 ◽  
Vol 45 (11-12) ◽  
pp. 1093-1099
Author(s):  
Abdulrhman Alsayari ◽  
Yahya I Asiri ◽  
Abdullatif Bin Muhsinah ◽  
Mohd. Zaheen Hassan

We report the design, synthesis, and in vitro antimicrobial evaluation of functionalized pyrazoles containing a hydrazono/diazenyl moiety. Among these newly synthesized derivatives, 4-[2-(4-chlorophenyl)hydrazono]-5-methyl-2-[2-(naphthalen-2-yloxy)acetyl]-2,4-dihydro-3 H-pyrazol-3-one is a promising antimicrobial agent against Staphylococcus aureus (minimum inhibitory concentration 0.19 μg mL−1). Structure–activity relationship studies reveal that the electronic environment on the distal phenyl ring has a considerable effect on the antimicrobial potential of the hybrid analogues. Molecular docking studies into the active site of S. aureus dihydrofolate reductase also prove the usefulness of hybridizing a pyrazole moiety with azo and hydrazo groups in the design of new antimicrobial agents.


2015 ◽  
Vol 13 (19) ◽  
pp. 5497-5509 ◽  
Author(s):  
Lan-Zhi Wang ◽  
Xiao-Qing Li ◽  
Ying-Shuang An

36 novel 1,5-benzodiazepine derivatives were synthesized and evaluated for their in vitro antimicrobial activity. The results revealed that most of the 1,5-benzodiazepine derivatives exhibited considerable potency against all of the tested strains.


2020 ◽  
Vol 16 ◽  
Author(s):  
M. T. Sulthana ◽  
V. Alagarsamy ◽  
K. Chitra

Background: Although exhaustive efforts to prevent and treat tuberculosis (TB) was taken the problem still continues due to multi-drug-resistant (MDR) and extensively drug resistant TB (XDR-TB). It clearly highlights the urgent need to develop novel “druggable” molecules for the co-infection treatment and strains of MDR-TB and XDR-TB. Objective: In this approach a hybrid molecule was created by merging two or more pharmacophores. Active site of targets may be addressed by each of the pharmacophores and proffers the opportunity for selectivity. In addition, it also reduced the undesirable side effects and drug-resistant. Methods: In this study, a novel quinazolinone analog was designed and synthesized by substituting thiourea nucleus and phenyl ring at N-3 and C-2 position of quinazoline ring respectively. All title compounds were tested for antitubercular activity by in-vitro M. tuberculosis and anti-human immunodeficiency virus (HIV) activity by MT-4 cell assay method. The agar dilution method was used to test the antibacterial potency of entire prepared derivatives against various strains of gram positive and gram-negative microorganism. Results: The title compounds, 1-(substituted)-2-methyl-3-(4-oxo-2-phenyl quinazolin-3(4H)-yl) isothioureas (QTS1 – QTS15) are synthesized by reaction between key intermediate 3-amino-2-phenylquinazolin-4(3H)-one with various alkyl/aryl isothiocyanates followed by methylation with dimethyl sulphate. Among the series, compound 1-(3-chlorophenyl)-2-methyl-3-(4-oxo-2-phenyl quinazolin- 3(4H)-yl) isothioureas (QTS14) shown highest potency against B. subtilis, K. pneumonia and S. aureus at 1.6 µg/mL. The compound QTS14 exhibited the most potent antitubercular activity at with the MIC of 0.78 µg/mL and anti-HIV activity at 0.97µg/mL against HIV1 and HIV2. Conclusion: The results obtained from this study confirm that the synthesized and biologically evaluated quinazolines showed promising antimicrobial, antitubercular and anti-HIV activities. The new scaffolds for proffers plausible lead for further development and optimization to novel antitubercular and anti-HIV drugs.


2019 ◽  
Vol 31 (12) ◽  
pp. 2740-2744
Author(s):  
Anil Verma ◽  
Vinod Kumar ◽  
Ramesh Kataria ◽  
Joginder Singh

Eleven acetohydrazide linked pyrazole derivatives were designed and synthesized via condensation of acetohyadrazide with different substituted formyl pyrazole derivatives under mild reaction conditions. Synthesized compounds were characterized on the basis of IR, NMR (1H & 13C) and mass spectrometry. The antimicrobial activities of all the compounds were screened against four bacterial and two fungal strains. Among the synthesized compounds, three compounds viz. 6b, 6c and 6d were found as efficient antimicrobial agents in reference to the standard drugs viz. ciprofloxacin and amphotericin-B. Further, structure-activity relationship (SAR) study revealed that electron-withdrawing group enhances the antimicrobial potential of synthesized derivatives as compared to other groups present in the ring. Hence, among compounds 6b-c, compound 6d could be explored further against other microbes to prove its vitality.


1999 ◽  
Vol 43 (10) ◽  
pp. 2376-2382 ◽  
Author(s):  
Zhengxian Gu ◽  
Mark A. Wainberg ◽  
Nghe Nguyen-Ba ◽  
Lucille L’Heureux ◽  
Jean-Marc de Muys ◽  
...  

ABSTRACT (−)-β-d-1′,3′-Dioxolane guanosine (DXG) and 2,6-diaminopurine (DAPD) dioxolanyl nucleoside analogues have been reported to be potent inhibitors of human immunodeficiency virus type 1 (HIV-1). We have recently conducted experiments to more fully characterize their in vitro anti-HIV-1 profiles. Antiviral assays performed in cell culture systems determined that DXG had 50% effective concentrations of 0.046 and 0.085 μM when evaluated against HIV-1IIIB in cord blood mononuclear cells and MT-2 cells, respectively. These values indicate that DXG is approximately equipotent to 2′,3′-dideoxy-3′-thiacytidine (3TC) but 5- to 10-fold less potent than 3′-azido-2′,3′-dideoxythymidine (AZT) in the two cell systems tested. At the same time, DAPD was approximately 5- to 20-fold less active than DXG in the anti-HIV-1 assays. When recombinant or clinical variants of HIV-1 were used to assess the efficacy of the purine nucleoside analogues against drug-resistant HIV-1, it was observed that AZT-resistant virus remained sensitive to DXG and DAPD. Virus harboring a mutation(s) which conferred decreased sensitivity to 3TC, 2′,3′-dideoxyinosine, and 2′,3′-dideoxycytidine, such as a 65R, 74V, or 184V mutation in the viral reverse transcriptase (RT), exhibited a two- to fivefold-decreased susceptibility to DXG or DAPD. When nonnucleoside RT inhibitor-resistant and protease inhibitor-resistant viruses were tested, no change in virus sensitivity to DXG or DAPD was observed. In vitro drug combination assays indicated that DXG had synergistic antiviral effects when used in combination with AZT, 3TC, or nevirapine. In cellular toxicity analyses, DXG and DAPD had 50% cytotoxic concentrations of greater than 500 μM when tested in peripheral blood mononuclear cells and a variety of human tumor and normal cell lines. The triphosphate form of DXG competed with the natural nucleotide substrates and acted as a chain terminator of the nascent DNA. These data suggest that DXG triphosphate may be the active intracellular metabolite, consistent with the mechanism by which other nucleoside analogues inhibit HIV-1 replication. Our results suggest that the use of DXG and DAPD as therapeutic agents for HIV-1 infection should be explored.


2022 ◽  
Author(s):  
Mohammed CHALKHA ◽  
Mohamed Akhazzane ◽  
Fatima Zahrae Moussaid ◽  
Ossama Daoui ◽  
Asmae Nakkabi ◽  
...  

In this work, we report the synthesis of some new pyrazole derivatives via an efficient and practical procedure. The structures of the obtained compounds were established using different spectroscopic techniques...


Author(s):  
Jade L. L. Teng ◽  
Elaine Chan ◽  
Asher C. H. Dai ◽  
Gillian Ng ◽  
Tsz Tuen Li ◽  
...  

Both typhoidal and non-typhoidal salmonellae are included in the top 15 drug-resistant threats described by the Center for Disease Control and Prevention of the United States. There is an urgent need to look for alternative antibiotics for the treatment of Salmonella infections. We examined the in vitro susceptibilities of ceftolozane/tazobactam and six other antibiotics on typhoidal and non-typhoidal salmonellae, including isolates that are extended-spectrum β-lactamase (ESBL)-positive, using the broth microdilution test. Of the 313 (52 typhoidal and 261 non-typhoidal) Salmonella isolates tested, 98.7% were susceptible to ceftolozane/tazobactam. Based on the overall MIC 50/90 values, Salmonella isolates were more susceptible to ceftolozane/tazobactam (0.25/0.5 mg/L) compared to all other comparator agents: ampicillin (≥64/≥64 mg/L), levofloxacin (0.25/1 mg/L), azithromycin (4/16 mg/L), ceftriaxone (≤0.25/4 mg/L), chloramphenicol (8/≥64 mg/L) and trimethoprim/sulfamethoxazole (1/≥8 mg/L). When comparing the activity of the antimicrobial agents against non-typhoidal Salmonella isolates according to their serogroup, ceftolozane/tazobactam had the highest activity (100%) against Salmonella serogroups D, G, I and Q isolates, whereas the lowest activity (85.7%) was observed against serogroup E isolates. All the 10 ESBL-producing Salmonella (all non-typhoidal) isolates, of which 8 were CTX-M-55-producers and 2 were CTX-M-65-producers, were sensitive to ceftolozane/tazobactam albeit with a higher MIC 50/90 value (1/2 mg/L) than non-ESBL-producers (0.25/0.5 mg/L). In summary, our data indicate that ceftolozane/tazobactam is active against most strains of both typhoidal and non-typhoidal salmonellae and also active against ESBL-producing salmonellae.


2020 ◽  
Vol 44 (6) ◽  
pp. 2247-2255
Author(s):  
Qifan Zhou ◽  
Lina Jia ◽  
Fangyu Du ◽  
Xiaoyu Dong ◽  
Wanyu Sun ◽  
...  

A novel series of pyrrole-3-carboxamides targeting EZH2 have been designed and synthesized. The structure–activity relationships were summarized by combining with in vitro biological activity assay and docking results.


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