Antibacterial activity of acyl and epoxide derivatives of β-sitosterol and cycloartanes

Two ether and one ester derivatives of the 4-nitro-3-hydroxybenzoic acid were synthesized and characterized. The in vitro antimicrobial and cytotoxic activities of the three novel compounds were also evaluated. The aromatic derivatives showed antibacterial activity against one of the four microorganisms tested and two compounds (C8 and NOBA) had a lower IC50 in HeLa cells.

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The Effect of N-4 Substituent on Antibacterial Activity of Novel Hydroxymethyl/Aminomethyl Derivatives of 1,2,4-Triazole-3-thione

Letters in Drug Design & Discovery ◽

10.2174/157018012800673056 ◽

2012 ◽

Vol 9 (6) ◽

pp. 633-637 ◽

Cited By ~ 1

Author(s):

Tomasz Plech ◽

Monika Wujec ◽

Urszula Kosikowska ◽

Anna Malm ◽

Magdalena Barylka ◽

...

Keyword(s):

Antibacterial Activity ◽

Aminomethyl Derivatives ◽

Derivatives Of

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Structure-Activity Relationship and Antimicrobial Evaluation of N-Phenylpyrazole Curcumin Derivatives

Current Bioactive Compounds ◽

10.2174/1573407215666190124115010 ◽

2020 ◽

Vol 16 (4) ◽

pp. 481-488

Author(s):

Heli Sanghvi ◽

Satyendra Mishra

Keyword(s):

Antibacterial Activity ◽

Gram Negative Bacteria ◽

Pyrazole Derivatives ◽

Gram Positive ◽

Gram Negative ◽

E Coli ◽

Curcumin Derivatives ◽

Structure Activity ◽

Electron Donating Groups ◽

Derivatives Of

Background: Curcumin, one of the most important pharmacologically significant natural products, has gained significant consideration among scientists for decades since its multipharmacological activities. 1, 3-Dicarbonyl moiety of curcumin was found to be accountable for the rapid degradation of curcumin molecule. The aim of present work is to replace 1, 3-dicarbonyl moiety of curcumin by pyrazole and phenylpyrazole derivatives with a view to improving its stability and to investigate the role of substitution in N-phenylpyrazole curcumin on its antibacterial activity against both Gram-positive as well as Gram-negative bacteria. Methods: Pyrazole derivatives of curcumin were prepared by heating curcumin with phenyhydrazine/ substituted phenyhydrazine derivatives in AcOH. The residue was purified by silica gel column chromatography. Structures of purified compounds were confirmed by 1H NMR and Mass spectroscopy. The synthesized compounds were evaluated for their antibacterial activity by the microdilution broth susceptibility test method against gram positive (S. aureus) and gram negative (E. coli). Results: Effects of substitution in N-phenylpyrazole curcumin derivatives against S. aureus and E. coli were studied. The most active N-(3-Nitrophenylpyrazole) curcumin (12) exhibits twenty-fold more potency against S. aureus (MIC: 10μg/mL)) and N-(2-Fluoroophenylpyrazole) curcumin (5) fivefold more potency against E. coli (MIC; 50 μg/mL) than N-phenylpyrazole curcumin (4). Whereas, a remarkable decline in anti-bacterial activity against S. aureus and E. coli was observed when electron donating groups were incorporated in N-phenylpyrazole curcumin (4). Comparative studies of synthesized compounds suggest the effects of electron withdrawing and electron donating groups on unsubstituted phenylpyrazole curcumin (4). Conclusion: The structure-activity relationship (SAR) results indicated that the electron withdrawing and electron donating at N-phenylpyrazole curcumin played key roles for their bacterial inhibitory effects. The results of the antibacterial evaluation showed that the synthesized pyrazole derivatives of curcumin displayed moderate to very high activity in S. aureus. In conclusion, the series of novel curcumin derivatives were designed, synthesized and tested for their antibacterial activities against S. aureus and E. coli. Among them, N-(3-Nitrophenylpyrazole curcumin; 12) was most active against S. aureus (Gram-positive) and N-(2-Fluoroophenylpyrazole) curcumin (5) against E. coli (Gram-negative) bacteria.

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Synthesis of substituted-amidine derivatives of avibactam and synergistic antibacterial activity with meropenem

Mendeleev Communications ◽

10.1016/j.mencom.2021.07.020 ◽

2021 ◽

Vol 31 (4) ◽

pp. 498-500

Author(s):

Jian Sun ◽

Lili He ◽

Yuanyu Gao ◽

Lijuan Zhai ◽

Jingwen Ji ◽

...

Keyword(s):

Antibacterial Activity ◽

Derivatives Of ◽

Synergistic Antibacterial Activity

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Synthesis and antibacterial activity of O-methyl derivatives of azalide antibiotics: II. 6-OMe derivatives VIA clarithromycin

Bioorganic & Medicinal Chemistry Letters ◽

10.1016/s0960-894x(98)00227-3 ◽

1998 ◽

Vol 8 (11) ◽

pp. 1321-1326 ◽

Cited By ~ 13

Author(s):

Sherman T. Waddell ◽

Gina M. Santorelli ◽

Timothy A. Blizzard ◽

Amy Graham ◽

James Occi

Keyword(s):

Antibacterial Activity ◽

Methyl Derivatives ◽

Derivatives Of

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Alkaloid-Rich Crude Extracts, Fractions and Piperamide Alkaloids of Piper guineense Possess Promising Antibacterial Effects

Antibiotics ◽

10.3390/antibiotics7040098 ◽

2018 ◽

Vol 7 (4) ◽

pp. 98 ◽

Cited By ~ 5

Author(s):

Eunice Mgbeahuruike ◽

Pia Fyhrquist ◽

Heikki Vuorela ◽

Riitta Julkunen-Tiitto ◽

Yvonne Holm

Keyword(s):

Antibacterial Activity ◽

Pathogenic Bacteria ◽

Bacterial Resistance ◽

Hot Water ◽

Bacterial Strains ◽

Inhibitory Effects ◽

Piper Guineense ◽

E Coli ◽

Growth Inhibitory ◽

Derivatives Of

Piper guineense is a food and medicinal plant commonly used to treat infectious diseases in West-African traditional medicine. In a bid to identify new antibacterial compounds due to bacterial resistance to antibiotics, twelve extracts of P. guineense fruits and leaves, obtained by sequential extraction, as well as the piperine and piperlongumine commercial compounds were evaluated for antibacterial activity against human pathogenic bacteria. HPLC-DAD and UHPLC/Q-TOF MS analysis were conducted to characterize and identify the compounds present in the extracts with promising antibacterial activity. The extracts, with the exception of the hot water decoctions and macerations, contained piperamide alkaloids as their main constituents. Piperine, dihydropiperine, piperylin, dihydropiperylin or piperlonguminine, dihydropiperlonguminine, wisanine, dihydrowisanine and derivatives of piperine and piperidine were identified in a hexane extract of the leaf. In addition, some new piperamide alkaloids were identified, such as a piperine and a piperidine alkaloid derivative and two unknown piperamide alkaloids. To the best of our knowledge, there are no piperamides reported in the literature with similar UVλ absorption maxima and masses. A piperamide alkaloid-rich hexane leaf extract recorded the lowest MIC of 19 µg/mL against Sarcina sp. and gave promising growth inhibitory effects against S. aureus and E. aerogenes as well, inhibiting the growth of both bacteria with a MIC of 78 µg/mL. Moreover, this is the first report of the antibacterial activity of P. guineense extracts against Sarcina sp. and E. aerogenes. Marked growth inhibition was also obtained for chloroform extracts of the leaves and fruits against P. aeruginosa with a MIC value of 78 µg/mL. Piperine and piperlongumine were active against E. aerogenes, S. aureus, E. coli, S. enterica, P. mirabilis and B. cereus with MIC values ranging from 39–1250 µg/mL. Notably, the water extracts, which were almost devoid of piperamide alkaloids, were not active against the bacterial strains. Our results demonstrate that P. guineense contains antibacterial alkaloids that could be relevant for the discovery of new natural antibiotics.

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SYNTHESIS AND ANTIMICROBIAL EVALUATION OF QUINAZOLINONE PEPTIDE DERIVATIVES

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2017.v10s4.21329 ◽

2017 ◽

Vol 10 (16) ◽

pp. 7 ◽

Cited By ~ 2

Author(s):

Bhupinder Kapoor ◽

Arshid Nabi ◽

Reena Gupta ◽

Mukta Gupta

Keyword(s):

Antibacterial Activity ◽

Amino Acid ◽

Antimicrobial Agents ◽

Methyl Esters ◽

Standard Drug ◽

Amino Acid Peptide ◽

Chemical Structures ◽

1H Nuclear Magnetic Resonance ◽

Peptide Derivatives ◽

Derivatives Of

Objective: The increased microbial resistance against commercially available drugs initiated the development of novel and safe antimicrobial agents in last few decades. In this view, a series of amino acid/dipeptide derivatives of quinazolin-3(4H)-one was synthesized and was evaluated for their antimicrobial potential.Method: Synthesis of amino acid/peptide derivatives were carried out by coupling 5-(2-(2-chlorophenyl)-4-oxoquinazolin-3(4H)-yl)-2-hydroxy benzoic acid with amino acid/dipeptide methyl esters in the presence of dicyclohexylcarbodiimide and N-methylmorpholine. The chemical structures of synthesized compounds were characterized by 1H nuclear magnetic resonance and infrared spectroscopy and were screened for antibacterial activity by disc diffusion method.Results: All the synthesized derivatives exhibited moderate to significant antibacterial activity against both Gram-positive and Gram-negative bacteria. The potency of compound 5d was comparable to standard drug ciprofloxacin in all the strains of bacteria used. The compound 5a was found to be more active against Streptococcus pyogenes and Staphylococcus aureus while compound 5c against Pseudomonas aeruginosa and Escherichia coli. Conclusion: Peptide derivatives of quinazolinone are promising antimicrobial agent and can be used for the synthesis of other novel compounds.

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