Evaluation of Antiplasmodial Potential of C2 and C8 Modified Quinolines: in vitro and in silico Study

2019 ◽  
Vol 15 (7) ◽  
pp. 790-800 ◽  
Author(s):  
Rakesh Kumar ◽  
Ritika Sharma ◽  
Inder Kumar ◽  
Pooja Upadhyay ◽  
Ankit Kumar Dhiman ◽  
...  

Background: Malaria remains a common life-threatening infectious disease across the globe due to the development of resistance by Plasmodium parasite against most antimalarial drugs. The situation demands new and effective drug candidates against Plasmodium. Objectives: The objective of this study is to design, synthesize and test novel quinoline based molecules against the malaria parasite. Methods: C2 and C8 modified quinoline analogs obtained via C-H bond functionalization approach were synthesized and evaluated for inhibition of growth of P. falciparum grown in human red blood cells using SYBR Green microtiter plate based screening. Computational molecular docking studies were carried out with top fourteen molecules using Autodoc software. Results: The biological evaluation results revealed good activity of quinoline-8-acrylate 3f (IC50 14.2 µM), and the 2-quinoline-α-hydroxypropionates 4b (IC50 6.5 µM), 4j (IC50 5.5 µM) and 4g (IC50 9.5 µM), against chloroquine sensitive Pf3D7 strain. Top fourteen molecules were screened also against chloroquine resistant Pf INDO strain and the observed resistant indices were found to lie between 1 and 7.58. Computational molecular docking studies indicated a unique mode of binding of these quinolines to Falcipain-2 and heme moiety, indicating these to be the probable targets of their antiplasmodial action. Conclusion: An important finding of our work is the fact that unlike Chloroquine which shows a resistance Index of 15, the resistance indices for the most promising molecules studied by us were about one indicating equal potency against drug sensitive and resistant strains of the malaria parasite.

2020 ◽  
Author(s):  
Mohsinul Mulk Bacha ◽  
Humaira Nadeem ◽  
Shafiq Ur Rehman ◽  
Sadia Sarwar ◽  
Aqeel Imran ◽  
...  

Abstract In diabetes, increased accumulation of sorbitol has been associated with diabetic complications through polyol pathway. Aldose reductase (AR) is one of the key factors involved in reduction of glucose to sorbitol, thereby its inhibition is considered to be important for the management of diabetic complications. In the present study, a series of seven 4-oxo-2-thioxo-1,3-thiazolidin-3-yl acetamide derivatives 3(a-g) were synthesized by the reaction of 5-(4-hydroxy-3-methoxybenzylidene)-4-oxo-2-thioxo-1,3-thiazolidin-3-yl acetic acid (2a) and 5-(4-methoxybenzylidene)-4-oxo-2-thioxo-1,3-thiazolidin-3-yl acetic acid (2b) with different amines. The synthesized compounds 3(a-g) were investigated for their in vitro aldehyde reductase (ALR1) and aldose reductase (ALR2) enzyme inhibitory potential. Compound 3c, 3d, 3e, and 3f showed ALR1 inhibition at lower micromolar concentration whereas all the compounds were more active than the standard inhibitor valproic acid. Most of the compounds were active against ALR2 but compound 3a and 3f showed higher inhibition than the standard drug sulindac. Overall the most potent compound against aldose reductase was 3f with an inhibitory concentration of 0.12 ± 0.01 µM. In vitro results showed that vanillin derivatives exhibited better activity against both aldehyde reductase and aldose reductase. The molecular docking studies were carried out to investigate the binding affinities of synthesized derivatives with both ALR1 and ALR2.


2021 ◽  
Author(s):  
Gül Özdemir ◽  
Namık Kılınç ◽  
Sevda Manap ◽  
Murat Beytur ◽  
Muzaffer Alkan ◽  
...  

A series of 2-ethoxy-4-{[3-alkyl(aryl)-4,5-dihydro-1H-1,2,4-triazol-5-on-4-yl]-azomethine}-phenyl benzenesulfonates (3) were synthesized from the reactions of 3-alkyl(aryl)-4-amino-4,5-dihydro-1H-1,2,4-triazol-5-ones (1) with 2-ethoxy-4-formyl-phenyl benzenesulfonate (2). N-acetyl derivatives (4) of compounds 3 were also obtained. Then, the compounds 3 have been treated with morpholine and 2,6-dimethylmorpholine in the presence of formaldehyde to synthesize 2-ethoxy-4-{[1-(morpholine-4-yl-methyl)-3-alkyl(aryl)-4,5-dihydro-1H-1,2,4-triazol-5-on-4-yl]-azomethine}-phenyl benzenesulfonates (5) and 2-ethoxy-4-{[1-(2,6-dimethylmorpholine-4-yl-methyl)-3-alkyl(aryl)-4,5-dihydro-1H-1,2,4-triazol-5-on-4-yl]-azomethine}-phenyl benzenesulfonates (6), respectively. The structures of twenty-six new compounds were identified by using elemental analysis, IR, 1H NMR, 13C NMR, and MS spectral data. In addition, in vitro antibacterial activities of the new compounds were evaluated against six bacteria such as Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus subtilis, Bacillus cereus and Klepsiella pneumonia according to agar well diffusion method. Furthermore, in order to determine the possible antidiabetic properties of the synthesized 1,2,4-triazole derivatives, inhibition effects on the AR enzyme were investigated and molecular docking studies were carried out to determine the receptor-ligand interactions of these compounds. IC50 values of triazole-derived compounds (6a, 6b, 6d-g) against AR enzyme were determined as 0.95 µM, 0.75 µM, 1.83 µM, 0.62 µM, 1.05 µM, 1.06 µM, respectively. Considering the docking scores and binding energies obtained docking studies, it has been shown that molecules fit very well to the active site of the AR enzyme.


2020 ◽  
Vol 17 (3) ◽  
pp. 170-183
Author(s):  
Minaxi Saini ◽  
Dinesh Kumar Mehta ◽  
Rina Das

Chemical modification of pyridazinone may lead to a potent therapeutic agent. In this study, biological properties of pyridazinone derivatives were evaluated by assessing their antimicrobial and in-vitro antioxidant activities. The reaction of a mucochloric acid and 3-chloro-phenylhydrazine hydrochloride led to the formation of 5-aryl-4-chloro-2-(3-chloro-phenyl)-2H-pyridazin-3-one derivatives 2(a-j). The target compounds were synthesized using nucleophilic substitution reaction. In-silico molecular docking studies of the synthesized compounds were carried out with the help of V-Life Science MDS 4.6 software using GRIP batch docking method to find out which derivative had a better docking. The newly synthesized compounds were characterized by FTIR, 1HNMR, 13C-NMR, MS, and elemental analysis. Antimicrobial and in-vitro antioxidant activity study of the novel synthesized compounds were screened. Compounds 2f and 2g showed good antimicrobial having an MIC 12.5 μg/mL against Staphylococcus aureus and Candida albicans and in-vitro antioxidant activities having an IC50 50.84. The experimental results were further supported by molecular docking analysis with better interaction patterns.


2020 ◽  
Vol 17 (7) ◽  
pp. 873-883
Author(s):  
Pulabala Ramesh ◽  
Vankadari Srinivasa Rao ◽  
Puchakayala Muralidhar Reddy ◽  
Katragadda Suresh Babu ◽  
Mutheneni Srinivasa Rao

Background:: Most of the currently available pharmaceutical drugs are either natural products or analogues of natural products. Flavonoids are plant based natural polyphenolic compounds which exhibit a wide range of biological activities. Chrysin, a natural flavone, exhibits several biological activities like antiallergic, anti-inflammatory and anticancer. Many efforts were made to enhance the biological activity of chrysin. In continuation of our work on synthetic modifications of chrysin, amino-alcohol containing heterocyclic moiety is linked to chrysin at C (7) position to enhance its biological activity. Methods:: A series of new C (7) modified analogues of chrysin (3a-k) have been designed and synthesized in two steps. Chrysin, on reacting with epichlorohydrin in the presence of K2CO3 in DMF gave epoxide (2) which was made to react with cyclic secondary amines in the presence of LiBr to form the designed products (3a-k). All the synthesized compounds (3a-k) were well characterized by 1H NMR, 13C NMR and mass spectral data. The synthesized analogues (3a-k) were screened for their in vitro biological activities against a panel of bacterial and fungal strains. Molecular docking studies were also performed on these compounds with E. coli FabH (1HNJ) and S. cerevisiae (5EQB) enzymes, to support the observed biological activities. Results:: A series of new 2-hydroxy 3-amino chrysin derivatives (3a-k) were synthesized in two steps, starting with chrysin and their structures were characterized by spectral analysis. In vitro biological activities of these analogues against a panel of bacterial and fungal strains indicated that some of the derivatives manifested significant activities compared to standard drugs. Molecular docking and binding energy values were also correlated with experimental antimicrobial screening results. Lipinski’s “rule of five” is also obeyed by these analogues (3a-k) and exhibit drug-likeness. Conclusion:: In the present study, a series of new C (7) modified chrysin analogues (3a-k) were synthesized and tested for their in vitro antimicrobial activities. These biological studies indicated that some of the derivatives exhibited moderate to good antimicrobial activities compared to standard drugs. Molecular docking studies performed on these compounds correlated with the experimental antimicrobial activities. The results obtained in the study will be useful in establishing new drug entities to control the pathogenic epidemics.


Sign in / Sign up

Export Citation Format

Share Document