scholarly journals Microwave and Conventional Study of Coumarin-Oxadiazole Adducts and their Anti-Microbial Evaluation

Folia Medica ◽  
2021 ◽  
Vol 63 (1) ◽  
pp. 105-112
Author(s):  
Khushal Kapadiya ◽  
Piyush Dholaria
Keyword(s):  
Microwave Synthesis ◽  
Industrial Applications ◽  
Spectroscopic Techniques ◽  
Reference Drug ◽  
Gram Positive Bacteria ◽  
In Vitro Antibacterial Activity ◽  
Greener Synthesis ◽  
Conventional Study ◽  
Synthesis Approach

Introduction: Nowadays, researchers are progressively concentrated to generate economical, affordable and also greener synthesis approach for the synthesis of various heterocycles. On look at the beauty of coumarin molecules and oxazoles, it seems to be lead  molecules in the anti-microbial area.  Aim: With the target to identify efficient molecules, we studied 2-oxo-2H-chromen-4-yl-2-((5-substituted aryl-1,3,4-oxadiazol-2-yl) thio)acetate derivatives using two synthetic protocol/methods, i.e. conventional synthesis and microwave-based synthesis. Materials and methods: Two simultaneous methods, i.e. conventional and microwave synthesis have been used for the synthe-sis of 2-oxo-2H-chromen-4-yl-2-((5-substituted aryl-1,3,4-oxadiazol-2-yl)thio)acetate (6a-l) derivatives. The desired molecules were synthesized by conventional and microwave synthesis and a comparative study was carried out to identify an easy route for industrial applications. The confirmations of the compounds were carried out by spectroscopic techniques such as IR, 1H NMR, 13C NMR, mass spectra and elemental analysis.  Results: All synthesized compounds were evaluated for their in-vitro antibacterial activity against gram-positive bacteria (Staphylococcus aureus, Staphylococcus pyogenes), gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa), and antifungal activity (Candida albicans, Aspergillus niger).  Conclusions: All conventional synthesis of final coumarin derivatives were completed within 4-6 h. While that of microwave-based reaction took comparatively more reaction time. Surprisingly, the compounds 6f and 6g could not be synthesized by microwave radiation even after 32 minutes of irradiation. As to the medicinal application part, microbial evaluation of synthesized analogues showed that the compounds 6b, 6e, 6d, and 6j were found more potent in comparison to the reference drug. 

scholarly journals In Vitro Activity of S-3578, a New Broad-Spectrum Cephalosporin Active against Methicillin-Resistant Staphylococci

2003 ◽  
Vol 47 (3) ◽  
pp. 923-931 ◽  
Author(s):  
Takaji Fujimura ◽  
Yoshinori Yamano ◽  
Isamu Yoshida ◽  
Jingoro Shimada ◽  
Shogo Kuwahara
Keyword(s):  
Antibacterial Activity ◽  
Population Analysis ◽  
Low Frequency ◽  
Methicillin Resistant ◽  
Gram Positive Bacteria ◽  
Highly Active ◽  
In Vitro Antibacterial Activity ◽  
Mrsa Strains ◽  
Time Kill

ABSTRACT The in vitro antibacterial activity of S-3578, a new parenteral cephalosporin, against clinical isolates was evaluated. The MICs of the drug at which 90% of the isolates were inhibited were 4 μg/ml for methicillin-resistant Staphylococcus aureus (MRSA) and 2 μg/ml for methicillin-resistant Staphylococcus epidermidis, which were fourfold higher than and equal to those of vancomycin, respectively. The anti-MRSA activity of S-3578 was considered to be due to its high affinity for penicillin-binding protein 2a (50% inhibitory concentration, 4.5 μg/ml). In time-kill studies with 10 strains each of MRSA and methicillin-susceptible S. aureus, S-3578 caused more than a 4-log10 decrease of viable cells on the average at twice the MIC after 24 h of exposure, indicating that it had potent bactericidal activity. Furthermore, in population analysis of MRSA strains with heterogeneous or homogeneous resistance to imipenem, no colonies emerged from about 109 cells on agar plates containing twice the MIC of S-3578, suggesting the low frequency of emergence of S-3578-resistant strains from MRSA. S-3578 was also highly active against penicillin-resistant Streptococcus pneumoniae (PRSP), with a MIC90 of 1 μg/ml, which was comparable to that of ceftriaxone. S-3578 also had antibacterial activity against a variety of gram-negative bacteria including Pseudomonas aeruginosa, though its activity was not superior to that of cefepime. In conclusion, S-3578 exhibited a broad antibacterial spectrum and, particularly, had excellent activity against gram-positive bacteria including methicillin-resistant staphylococci and PRSP. Thus, S-3578 was considered to be worthy of further evaluation.

scholarly journals Synthesis and Biological Screening of Novel 5-(5-Aryl-1-phenyl-1H-pyrazol-3-yl)-3-aryl-1,2,4-oxadiazole Derivatives

2021 ◽  
Vol 34 (1) ◽  
pp. 209-215
Author(s):  
Pravin S. Kulkarni ◽  
Swapnil R. Sarda ◽  
Amol U. Khandebharad ◽  
Mazahar Farooqui ◽  
Brijmohan R. Agrawal
Keyword(s):  
Escherichia Coli ◽  
Antibacterial Activity ◽  
Bacillus Subtilis ◽  
Spectroscopic Techniques ◽  
Biological Screening ◽  
Cyclocondensation Reaction ◽  
In Vitro Antibacterial Activity ◽  
Oxadiazole Derivatives ◽  
In Vitro Antifungal Activity

A new series of 5-(5-aryl-1-phenyl-1H-pyrazol-3-yl)-3-aryl-1,2,4-oxadiazole (6a-o) have been synthesized by a cyclocondensation reaction of ethyl 5-(4-chlorophenyl)-1-phenyl-1H-pyrazole-3- carboxylate (3a-c) with aryl imidoxime (5a-e). The newly synthesized pyrazolyl-1,2,4-oxadiazole (6a-o) derivatives were characterized by spectroscopic techniques and screened for in vitro antibacterial activity against Bacillus subtilis (NCIM 2063), Staphylococcus albus (NCIM 2178), Escherichia coli (NCIM 2574), Proteus mirabilis (NCIM 2388) and in vitro antifungal activity against Aspergillus niger (ATCC 504) Candida albicans (NCIM 3100).

scholarly journals A Preliminary Investigation on the In-Vitro Antibacterial Activities of Cave Actinomycetes

2021 ◽  
Vol 16 (3) ◽  
Author(s):  
Asifa Mushtaq ◽  
Musharaf Gul ◽  
Seema Rawat ◽  
Jay Krishan Tiwari
Keyword(s):  
Antibacterial Activity ◽  
Secondary Metabolites ◽  
Scientific Community ◽  
Preliminary Investigation ◽  
Antibacterial Properties ◽  
Antibacterial Activities ◽  
Industrial Applications ◽  
Gram Positive Bacteria ◽  
Streptomyces Genus

Actinomycetes are prolific producers of secondary metabolites majority of which have phenomenal industrial applications. Actinomycetes recovered from cave habitats have generated a considerable interest among the scientific community with respect to their adaptability under such unique environmental conditions. Garhwal Himalaya, Uttarakhand abodes several pristine caves which have not been previously explored for the presence of actinomycetes. The present study has been undertaken to assess the in vitro antibacterial properties of actinomycetes recovered from some of the caves located in Garhwal Himalayan region. In the present study, a total of 127 actinomycetes were isolated from three distinct caves. Majority of the isolates exhibited antibacterial activity against gram-positive bacteria. Actinomycetes isolates RCM1 and SCMM1 were observed to evince promising antibacterial activities. Members of Streptomyces genus were found to be predominant in all the samples.

Rapid and efficient synthesis of newer heterocyclic 2-azetidinone and 5-benzylidine-4-oxo-thiazolidine compounds and their pharmacological studies

2019 ◽  
Author(s):  
Chem Int
Keyword(s):  
Inhibitory Effect ◽  
Diffusion Method ◽  
Spectroscopic Techniques ◽  
Antimicrobial Compounds ◽  
Efficient Synthesis ◽  
Proteus Vulgaris ◽  
Bacterial Strains ◽  
Pharmacological Studies ◽  
In Vitro Antibacterial Activity

A straightforward rapid and efficient protocol for the synthesis of 2-azetidinone (D1-10) and 5-benzylidine-4-oxo-thiazolidine (F1-10) has been designed and synthesized in order to find newer antimicrobial compounds. The structure of entitle compounds have been evaluated on the basis of various spectroscopic techniques FTIR, 1H-NMR, 13C-NMR as well as elemental microanalysis. The title compounds were screened for their preliminary in vitro antibacterial activity against a panel of selected pathogenic bacterial strains, Staphylococcus aureus (MTCC 96), Escherichia coli (MTCC 443), Proteus vulgaris (MTCC 426) and Pseudomonas aeruginosa (MTCC 424) using cup-plate agar diffusion method at 40 μg/ml concentration. Out of synthesized compounds, compound nos. D4, D5, D7, D8, D9 and D10 have shown outstanding inhibitory effect against all pathogens and consider as the best bioactive desired antibacterial analogue of the series as compare to standard drugs ampicilline and chloramphenicol.

Synthesis and Antimicrobial Evaluation of 1,3,4-Oxadiazole bearing Schiff Base Moiety

2020 ◽  
Vol 5 (1) ◽  
pp. 1-5
Author(s):  
K. Kapadiya ◽  
G. Dubal ◽  
Y. Bhola ◽  
P. Dholaria
Keyword(s):  
Streptococcus Pyogenes ◽  
Nmr Spectra ◽  
Gram Negative Bacteria ◽  
13C Nmr Spectra ◽  
Aspergillus Clavatus ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
In Vitro Antibacterial Activity ◽  
Antimicrobial Evaluation

A new series of 4-((5-(2-chlorophenyl)-1,3,4-oxadiazol-2-yl)methoxy)-N-(benzylidene derivatives)benzenamine (5a-k) have been synthesized and were screened for their in vitro antibacterial activity against Gram-positive bacteria (Pseudomonas aeruginosa, Streptococcus pyogenes), Gram-negative bacteria (Escherichia coli, Staphylococcus aureus) and antifungal activity (Candida albicans, Aspergillus niger, Aspergillus clavatus). Synthesized compounds were characterized by IR, mass (MS), 1H NMR and 13C NMR spectra. The synthesized compounds 5b, 5c, 5g and 5i showed potency in terms of antimicrobial activity against tested microorganisms.

scholarly journals Antimicrobial activity of DU-6681a, a parent compound of novel oral carbapenem DZ-2640.

1997 ◽  
Vol 41 (6) ◽  
pp. 1260-1268 ◽  
Author(s):  
M Tanaka ◽  
M Hohmura ◽  
T Nishi ◽  
K Sato ◽  
I Hayakawa
Keyword(s):  
Parent Compound ◽  
Inoculum Size ◽  
Gram Positive ◽  
Gram Positive Bacteria ◽  
Alkaline Conditions ◽  
In Vitro Antibacterial Activity ◽  
Acidic Conditions ◽  
Kill Curve ◽  
Time Kill

The in vitro antibacterial activity of DU-6681a, a parent compound of DZ-2640, against gram-positive and -negative bacteria was compared with those of penems and cephalosporins currently available. MICs at which 90% of the isolates are inhibited (MIC90s) of the compound for clinical isolates of methicillin-susceptible and -resistant Staphylococcus aureus and Staphylococcus epidermidis, including methicillin-susceptible and -resistant strains, were 0.10, 25, and 12.5 microg/ml, respectively. DU-6681a inhibited the growth of all strains of Streptococcus pyogenes and of penicillin-susceptible and -insusceptible Streptococcus pneumoniae at 0.006, 0.025, and 0.20 microg/ml, respectively, and MIC90s of the compound were 6.25 and >100 microg/ml for Enterococcus faecalis and Enterococcus faecium, respectively. MIC90s of DU-6681a were 0.20, 0.10, and 0.025 microg/ml for Haemophilus influenzae, Moraxella catarrhalis, and Neisseria gonorrhoeae, respectively. For Pseudomonas aeruginosa, the MIC50 and MIC90 of DU-6681a were 25 and 50 microg/ml, respectively. DU-6681a activity was not affected by different media, varied inoculum size (10(4) to 10(7) CFU), or the addition of human serum but was decreased under acidic conditions against gram-negative bacteria, under alkaline conditions against gram-positive bacteria, and in human urine, as was the activity of the other antibiotics tested. The frequency of spontaneous resistance to DU-6681a was less than or equal to those of the reference compounds. Time-kill curve studies demonstrated the bactericidal action of DU-6681a against S. aureus, S. pneumoniae, Escherichia coli, and H. influenzae.

scholarly journals Synthesis and Pharmacological Evaluation of Some New 2-Phenyl benzimidazoles Derivatives and their Schiff's Bases

2009 ◽  
Vol 6 (s1) ◽  
pp. S342-S346 ◽  
Author(s):  
Y. S. Chhonker ◽  
B. Veenu ◽  
S. R. Hasim ◽  
Niranjan Kaushik ◽  
Devendra Kumar ◽  
...  
Keyword(s):  
Antimicrobial Activities ◽  
Benzimidazole Derivatives ◽  
Spectroscopic Techniques ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
H Nmr ◽  
Ir Spectroscopic

Some new 2- phenyl benzimidazole derivatives were synthesised by cyclocondensation with appropriate reagents. The compounds synthesised were identified by1H NMR, FAB Mass and FT-IR spectroscopic techniques. All compounds studied in this work were screened for theirin vitroantimicrobial activities against the standard strains:Staphylococcus aureusATCC - 25923, ATCC - 441 andBacillus subtilisATCC- 6633 as gram positive,Escherichia coliATCC - 11775 andPseudomonas aeruginosaATCC 10145 as gram negative bacteria. Some of the compounds inhibited the growth of gram-positive bacteria (B. subtilisandS. aureus) at MIC values between 25 and 200 mg/mL. Some of the compounds exhibit antimicrobial activity against gram negative bacteria (E. coliandP. Aeruginosa) MIC values between 25 and 200 mg/mL.

scholarly journals Synthesis and Characterization of Some New Pyrazoline and Isoxazoline Derivatives as Antibacterial Agents

2016 ◽  
Vol 13 (3) ◽  
pp. 568-577
Author(s):  
Baghdad Science Journal
Keyword(s):  
Sodium Hydroxide ◽  
Antibacterial Agents ◽  
Amine Hydrochloride ◽  
Gram Negative Bacteria ◽  
Gram Positive Bacteria ◽  
In Vitro Antibacterial Activity ◽  
Derivatives Of ◽  
Number Of Bacteria

In this paper some chalcones (C1-C8) are prepared based on the reaction of one mole of substituted acetophenone with one mole of substituted benzaldehydes in the presence of (40%) sodium hydroxide as a base. Pyrazolines (P1–P8) are prepared from the reaction of chalcones (C1-C8) with hydrazine hydrate. Isoxazoline (I1-I8) is prepared from the reaction of chalcones (C1-C8) with hydroxyl amine hydrochloride in the presence of (10%) sodium hydroxide as a base. These compounds are characterized by using various physical and spectral methods. The compounds are screened for their in vitro antibacterial activity using gram-positive bacteria and gram-negative bacteria. Several derivatives of pyrazolines and isoxazolines are produced well to moderate activities against number of bacteria.

scholarly journals Design, synthesis and molecular modeling study of substituted indoline-2-ones and spiro[indole-heterocycles] with potential activity against Gram-positive bacteria

2021 ◽  
Vol 72 (1) ◽  
pp. 79-95
Author(s):  
Awwad Abdoh Radwan ◽  
Fares Kaed Aanazi ◽  
Mohammed Al-Agamy ◽  
Gamal Mohammad Mahrous
Keyword(s):  
Histidine Kinase ◽  
In Silico ◽  
Binding Mode ◽  
Antibacterial Activities ◽  
Hydroxy Ketone ◽  
Spectroscopic Techniques ◽  
Gram Positive ◽  
Gram Positive Bacteria ◽  
Chemical Structures

Abstract Longstanding and firsthand infectious diseases are challenging community health threats. A new series of isatin derivatives bearing β-hydroxy ketone, chalcone, or spiro-heterocycle moiety, was synthesized in a good yield. Chemical structures of the synthesized compounds were elucidated using spectroscopic techniques and elemental analysis. Antibacterial activities of the compounds were then evaluated in vitro and by in silico modeling. The compounds were more active against Gram-positive bacteria, Staphylococcus aureus (MIC = 0.026–0.226 mmol L−1) and Bacillus subtilis (MIC = 0.348–1.723 mmol L–1) than against Gram-negative bacteria (MIC = 0.817–7.393 mmol L–1). Only 3-hydroxy-3-(2-(2,5-dimethylthiophen-3-yl)-2-oxoethyl)indolin-2-one (1b) was found as active as imipenem against S. aureus (MIC = 0.026 mmol L–1). In silico docking of the compounds in the binding sites of a homology modeled structure of S. aureus histidine kinase-Walk allowed us to shed light on the binding mode of these novel inhibitors. The highest antibacterial activity of 1b is consistent with its highest docking score values against S. aureus histidine kinase.

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