Synthesis, spectroscopic characterization and computational chemical study of 5-cyano-2-thiouracil derivatives as potential antimicrobial agents

2018 ◽  
Vol 1155 ◽  
pp. 720-733 ◽  
Author(s):  
Sameh A. Rizk ◽  
Abeer M. El-Naggar ◽  
Azza A. El-Badawy

Flavonoids display a strong antioxidant and radical scavenging activity and seem to beassociated with reduced danger for certain chronic diseases, the prevention of some cardiovascular sicknesses and certain types of cancerous processes [1-4]. Flavonoids show also antiviral, antimicrobial, and anti-inflammatory activities, helpful on capillary fragility and prevent human platelet aggregation, antiulcer and antiallergenic [5-11]. Though, the actual in vivo mechanism of action is largely unknown. Most studies have attentivein vitro tests at amounts much higher than in humans,however few clinical investigations have been carried out around the diseases [12].Additional clinical trials are required to evaluate a more precise correlation between flavonoids consumption and human health benefits [13]. The possible mechanism of potential experimentalactionhas been studied [14]. Citrus juices attitude among the most significant phenolicrich dietary sources [15].


2015 ◽  
Vol 2015 ◽  
pp. 1-15 ◽  
Author(s):  
M. M. El-ajaily ◽  
H. A. Abdullah ◽  
Ahmed Al-janga ◽  
E. E. Saad ◽  
A. A. Maihub

La(III), Zr(IV), and Ce(IV) chelates of 2-[(4-[(Z)-1-(2-hydroxyphenyl)ethylidene]aminobutyl)-ethanimidoyl]phenol were synthesized and characterized by using several physical techniques. The Schiff base was obtained by refluxing of o-hydroxyacetophenone with 1,4-butanediamine in 2 : 1 molar ratio. The CHN elemental analysis results showed the formation of the Schiff base and the chelates has been found to be in 1 : 1 [M : L] ratio. The molar conductance measurements revealed that all the chelates are nonelectrolytes. Structural elucidations of the ligand and its chelates were based on compatible analytical and spectroscopic evidences. The infrared spectral data revealed that the Schiff base coordinates to the metal ions through active sites which are –OH and –C=N groups. According to the electronic spectral data, an octahedral geometry was proposed for the chelates. The synthesized ligand and its metal chelates were screened for their antimicrobial activity against two Gram negative (Escherichia coli, Salmonella kentucky) and two Gram positive (Lactobacillus fermentum, Streptococcus faecalis) bacterial strains, unicellular fungi (Fusarium solani), and filamentous fungi (Aspergillus niger). The activity data showed that the metal chelates have antibacterial and antifungal activity more than the parent Schiff base ligand against one or more bacterial or fungi species. The results also indicated that the metal chelates are higher sensitive antimicrobial agents as compared to the Schiff base ligand.


2020 ◽  
Vol 1222 ◽  
pp. 128821 ◽  
Author(s):  
Mohammed M. Matin ◽  
Md. S. Hasan ◽  
Monir Uzzaman ◽  
Md. Mosharef H. Bhuiyan ◽  
Sayed M. Kibria ◽  
...  

2021 ◽  
Vol 55 (5-6) ◽  
pp. 477-499
Author(s):  
FARHANA YASMIN ◽  
MOHAMMED R. AMIN ◽  
MOHAMMED A. HOSEN ◽  
MOHAMMED Z. H. BULBUL ◽  
SUJAN DEY ◽  
...  

Several carbohydrate-based drugs are currently being used to treat a number of diseases in humans worldwide. Thus, our research group has focused on the synthesis of new methyl α-D-mannopyranoside (MDM) derivatives and their antimicrobial evaluation through computational studies. A series of MDM derivatives (2-6) were synthesized through facile regioselective acylation, using the direct method affording 6-O-(3-chlorobenzoyl) derivatives. This isolated 6-O-derivative was further transformed to 2,3,4-tri-O-acyl derivatives, bearing a wide variety of functionalities in a single molecular framework. The structures of the newly designed molecules were elucidated with the aid of IR, 1H NMR, mass spectroscopy, and elemental analysis. The prediction of the activity spectra for the compounds (PASS) and their in vitro antimicrobial evaluation were performed, demonstrating them to be potential antimicrobial agents. The antimicrobial tests demonstrated that the compounds 3 and 5 were the most potent with the minimum inhibitory concentration (MIC) values, ranging from 0.312±0.01 to 1.25±0.03 mg/mL, and minimum bactericidal concentration (MBC) values, ranging from 0.625±0.02 to 2.50±0.05 mg/mL. A quantum chemical study was performed to calculate the thermodynamic, molecular orbital and electrostatic potential properties of the designed compounds. Molecular docking simulation was carried out against SARS-CoV-2 Mpro protein 7BQY and 6Y84 to investigate their binding energy and binding tactics with the viral protein, and better binding affinity than that of the parent drug was observed. Also, pharmacokinetic prediction revealed an improved drug-likeness profile for all MDM derivatives.


2021 ◽  
Vol 46 (2) ◽  
Author(s):  
I. G. Osigbemhe ◽  
M. E. Khan ◽  
A. P. Oviawe ◽  
M.L Ugheoke

Manganese(II) complexes of 2-{[(2-hydroxy-5-nitrophenyl) methylidene]amino} nicotinic acid derived from o-phenylenediamine and 5- nitrosalicaldehyde were synthesized and characterized by elemental analysis, using IR, 1HNMR, 13CNMR, and GCMS. They were screened against known disease causative microbes to establish their potentials as antimicrobial agents compared with national standards drugs. Results showed that, a Schiff base exhibited antimicrobial action against all the bacteria and most of the fungi with exception of Candidas. albicans isolate, which exhibited zero diameter zone of inhibition. It was also found that the synthesized Schiff base exhibited two digits purity range, implying that it was relatively stable. The metal complex was found to be more susceptible in overall biological activity due to the structural stability, showing their potency in pharmacognocy.


2021 ◽  
Vol 5 (2) ◽  
pp. 477-488
Author(s):  
G. Osigbemhe ◽  
M. E. Khan ◽  
A. Olusegun ◽  
H. D. Kabiru

Iron (II) complexes of 2-{[(2-hydroxy-5-methoxyphenyl) methylidene]amino} nicotinic acid derived from o-phenylenediamine and 5- methoxysalicaldehyde were synthesized and characterized by elemental analysis, using  UV-Visible, IR, 1HNMR, 13CNMR,  They were screened against known disease causative microbes to establish their effectiveness and efficacies as antimicrobial agents compared with national standards drugs, ampiclox and ketoconazole. Results showed that, the Schiff base exhibits antimicrobial action against all the bacteria and most of the fungi with exception of Candidas. albicans which exhibited naught diameter zone of inhibition. It was also found that the synthesized Schiff base exhibited two digits purity range, implying that it is relatively stable.  The metal complex was found to be more susceptible in overall biological activity than the Schiff base synthesized and studied due to their structural stability in relationship to its activity. This has opened another drug window for the remedy to human diseases caused by these microbes


2019 ◽  
Vol 14 (3) ◽  
pp. 129-135
Author(s):  
Xuelian Bai ◽  
Ronglu Yu ◽  
Mingzhu Li ◽  
Huawei Zhang

In order to search more antimicrobial natural products for new drug discovery, bioassay and chemical investigation of endophytic strains from Rumex madaio were carried out. Six fungal strains (numbered as L1, L6, L9, L10, R1, R2) were successfully isolated and their antimicrobial effects on three human pathogens, Escherichia coli, Staphyloccocus aureus and Candida albicans, were evaluated. The results indicated that ethyl acetate extracts of fermentation broth of these strains had no potent antimicorbial activity against E. coli and C. albicans while strains L1 and R1 had stronger inhibitory effects on S. aureus. On basis of morphological characteristics and 18S rRNA sequence analysis, strains L1 and R1 were respectively classified as Colletotrichum and Fusarium geni. The chemical study of strain R1 led to isolation of two known antimicrobial agents, dibutyl phthalate (1) and beauvericin (2).


Sign in / Sign up

Export Citation Format

Share Document