Synthesis and antimicrobial evaluation of some novel sulfonylamido-benzoxazoles

A series of 2-(p-substituted phenyl)-5-[(4-substituted phenyl) sulfonylamido]-benzoxazoles were synthesized and tested for their antimicrobial activities. The structures of the new derivatives were elucidated by spectral techniques. The minimum inhibitory concentrations (MIC) of the new benzoxazoles were determined against standard bacterial and fungal strains and drug-resistant isolates and compared to those of several reference drugs

Synthesis, Antimicrobial Activities of New Sulfonamidobenzoxazoles and Molecular Docking Studies on Escherichia coli TEM-1 β-Lactamase

β-Lactam antibiotics are frequently used for treatment of multi-drug resistant microbial infections and the most common mechanism of resistance against these antibiotics is bacterial β-lactamase production. Herein, we reported the design, synthesis and in vitro antimicrobial activities of some new 2-substituted-5-(2,4-dinitrophenylsulfonamido)benzoxazole derivatives. Compounds TN1, TN2, and TN3 were found to be significantly active against E. coli isolate which contains extended spectrum β-lactamase enzyme at the MIC value of 8 µg mL–1 and that is 4-fold higher than the reference drug ampicillin. We performed molecular docking studies into active site of Escherichia coli TEM-1 β-lactamase enzyme in order to predict the protein-ligand interactions. According to the docking results, compounds TN1, TN2, and TN3 showed strong interactions between the important active site residues which are responsible for the catalytic mechanism of TEM-1 β-lactamase enzyme and a good correlation is found with the experimental data. This work is licensed under a Creative Commons Attribution 4.0 International License

Synthesis and In vitro Antimicrobial Activity of Novel 2-(4-(Substituted-carboxamido)benzyl / phenyl)benzothiazoles

A new series of 2-[4-(4-substitutedbenzamido / phenylacetamido / phenylpropionamido) benzyl / phenyl]benzothiazole derivatives (6a−6w) were synthesized and evaluated for antibacterial and antifungal activities against Staphylococcus aureus, Bacillus subtilis, Klebsiella pneumoniae, Pseudomonas aeruginosa, Escherichia coli with their drug-resistant isolates and a yeast Candida albicans. Microbiological results indicated that the compounds possessed a broad spectrum of activity against the tested microorganisms at MIC values between 200 and 6.25 μg/ml. Compounds 6e and 6j exhibited the greatest activity with MIC values of 6.25 μg/ml against Pseudomonas aeruginosa, and Staphylococcus aureus isolate, respectively.(doi: 10.5562/cca2064

Synthesis and antimicrobial evaluation of novel 5-substituted-2-(p-tert-butylphenyl)benzoxazoles

In the present study, a series of nine novel 5-substituted-2-(p-tert-butylphenyl)benzoxazole derivatives have been synthesized and their structures confirmed by spectral techniques and also tested for their antimicrobial activities. The minimum inhibitory concentrations (MIC) of the new benzoxazoles have been determined against standard bacterial and fungal strains and drug-resistant isolates and compared to those of several reference drugs. The new benzoxazole derivatives are found to possess a broad spectrum of antibacterial activity with MIC values of 8-256 mu g/mL. Especially, compound 9 is more active than standard drugs ciprofloxacin and cefotaxime against E. coli isolate with a MIC value of 8 mu g/mL. Also new compounds are less active than fluconazole with a MIC value of 256 mu g/mL against C. albicans and its isolate except for compound 9 that shows better activity other compounds with a MIC value of >4 mu g/mL for their antifungal activity

Synthesis of some piperazinobenzoxazole derivatives and their antimicrobial properties

240-247<span style="font-size:11.0pt;mso-bidi-font-size: 10.0pt;font-family:" times="" new="" roman";mso-fareast-font-family:"times="" roman";="" mso-bidi-font-family:"times="" roman";letter-spacing:-.2pt;mso-ansi-language:="" en-us;mso-fareast-language:en-us;mso-bidi-language:ar-sa"="" lang="EN-US">A series of 2-(p-substitutedphenyl/benzyl)-5-[3-[4-[(p-chlorophenyl)/phenyl]piperazin-1-yl]propionamido]-benzoxazoles (<b style="mso-bidi-font-weight: normal">3-22) have been synthesized towards discovering new antimicrobial compounds in order to fight against pathogens, which have become resistant to antibiotics and are the cause of increased mortality and morbidity throughout the world. Structures of new derivatives have been elucidated by spectral techniques. New and previously synthesized benzoxazoles have been evaluated for their antibacterial and antifungal activity against standard strains, and their drug-resistant isolates in comparison with reference drugs. This study is aimed to investigate the efficacy of the antimicrobial effect of different amido bridges on the same homologue structures of benzoxazole compounds. Compounds 3-22 exhibit broad antibacterial activity with MIC (Minimum Inhibitory Concentration) values of 128-256 µg/mL against Staphylococcus aureus and its isolate except for derivative <b style="mso-bidi-font-weight: normal">7 that has a MIC value of 32 µg/mL against S. aureus isolate and compounds 3 and <b style="mso-bidi-font-weight: normal">22 which have <span style="font-size:11.0pt; mso-bidi-font-size:9.0pt;font-family:" times="" new="" roman";mso-fareast-font-family:="" "times="" roman";mso-bidi-font-family:"times="" roman";mso-ansi-language:="" en-us;mso-fareast-language:en-us;mso-bidi-language:ar-sa"="" lang="EN-US">MIC value of 512 µg/mL against S. aureus. Also, t<span style="font-size:9.0pt; font-family:" times="" new="" roman";mso-fareast-font-family:"arial="" unicode="" ms";="" mso-bidi-font-family:"times="" roman";mso-ansi-language:en-us;font-weight:="" normal"="" lang="EN-US">he tested compounds 3-22 possess low antifungal activity with MIC values of 128 µg/mL against Candida albicans in comparison with antifungal reference drugs, fluconazole and amphotericin B.</span

Synthesis and antimicrobial evaluation of novel 5-substituted-2-(<em>p</em>-tert-butylphenyl)benzoxazoles

385-389In the present study, a series of nine novel 5-substituted-2-(p-tert-butylphenyl)benzoxazole derivatives have been synthesized and their structures confirmed by spectral techniques and also tested for their antimicrobial activities. The minimum inhibitory concentrations (MIC) of the new benzoxazoles have been determined against standard bacterial and fungal strains and drug-resistant isolates and compared to those of several reference drugs. The new benzoxazole derivatives are found to possess a broad spectrum of antibacterial activity with MIC values of 8−256 µg/mL. Especially, compound 9 is more active than standard drugs ciprofloxacin and cefotaxime against E. coli isolate with a MIC value of 8 µg/mL. Also new compounds are less active than fluconazole with a MIC value of 256 µg/mL against C. albicans and its isolate except for compound 9 that shows better activity other compounds with a MIC value of >4 µg/mL for their antifungal activity

Design, synthesis, molecular docking, density functional theory and antimicrobial studies of some novel benzoxazole derivatives as structural bioisosteres of nucleotides

A series of some novel 2-(p-tert-butylphenyl)-5-(3-substituted-propionamido)benzoxazole derivatives have been designed, synthesized, evaluated for antimicrobial activity and have performed molecular docking studies against penicillin-binding protein 4 (PBP4) and active and allosteric site of PBP2a; were calculated some theoretical quantum parameters and absorption, distribution, metabolism and excretion (ADME) descriptors. B9 acted at minimum inhibitory concentration (MIC) = 8 mu g/mL against S. aureus, E. faecalis and their drug-resistant isolates and also formed with GLU145 (1.74 angstrom) and ILE144 (1.89 angstrom) two hydrogen bonds at allosteric site of PBP2a with Glide emodel score: -42.168. Delta E of compound B9 had moderate value of all compounds with 0.14742

Studıes on the synthesıs of 3-methyl-6-(substıtuted-urea/-thıourea)-2(3<i style="mso-bidi-font-style:normal">H</i>)-benzothıazolone derıvatıves and antımıcrobıal actıvıtıes

253-259A series of sixteen new urea and thiourea derivatives at position 6 of 3-methyl-2(3H)-benzothiazolone ring have been prepared and studied using IR, 1H NMR, mass spectra and elemental analysis. The urea and thiourea derivatives have been obtained by the reaction of 6-amino-3-methyl-2(3H)-benzothiazolone with appropriate isocyanates and isothiocyanates. The antibacterial, antifungal and antimycobacterial activities of the synthesized compounds have been evaluated in vitro using microdilution and microplate methods

Study on Synthesis and Biological Activity of Some Pyridopyridazine Derivatives

In this study, new pyrido {[}3,4-d]pyridazine derivatives were synthesized and evaluated for their in vitro antibacterial, antifungal and antimycobacterial activities. Among the synthesized compounds, compound 10 (1-(4-benzylpiperazin-1-yl) pyrido {[}3,4-d]pyridazin-4(3H)-one) and compound 12 (1-(4-benzylpiperidin-1-yl)pyrido {[}3,4-d]pyridazin-4(3H)-one) were found to have the highest antimycobacterial activity. However, all compounds were found ineffective against tested Gram-positive, Gram-negative bacteria and fungus