Antimicrobial and antioxidant activities of substituted halogenated coumarins

Abstract

Pathogens frequently display resistance to current drugs, which frequently lack selectivity/efficacy and have detrimental side effects. Thus, there is a constant need for novel therapeutic agents. Coumarins belong to the family of lactones, having a benzopyrone system that can be isolated from plants as well as total synthesis that can be carried out in the laboratory. To date, many chemical reactions have been established that can be used to synthesize coumarins. The synthesis of coumarins and their derivatives has attracted the attention of organic and medicinal chemists, as these are widely used as fragrances, pharmaceuticals and agrochemicals. In the present study, the antimicrobial and antioxidant activities of substituted coumarin analogue compounds have been screened. 3-(2-bromoacetyl)-2H-chromen-2-one (CMRN3) and 3-(2, 2-dibromoacetyl)-2H-chromen-2-one (CMRN6) showed bacterial growth inhibition for all the tested species except Klebsiella pneumonia and Bacillus stearothermophilus. CMRN4 and CMRN5 displayed moderate bacterial inhibition against Bacillus cereus, Micrococcus luteus, Staphylococcus aureus. CMRN3 and CMRN6 had a minimum inhibition concentration at 0.75 mg/ml against B. cereus, Bacillus coagulans, and Streptococcus faecalis. They displayed a minimum inhibitory concentration (MIC) of 1.5 mg/ml against Escherichia coli and S. aureus. (CMRN5) displayed an MIC at 0.75 mg/ml against M. luteus and 1.5 mg/ml against S. aureus. Compounds3-(2-bromoacetyl)-6-chloro-2H-chromen-2-one (CMRN4), 3-(2-aminothiazol-4-yl)-6-bromo-2H-chromen-2-one(CMRN7), 3-acetyl-6-bromo-2H-chromen-2-one (CMRN1) exhibited potent antioxidant activity at 85, 61 and 56%, respectively, as evaluated by the DPPH free radical method.

Discovery of New Coumarin-Based Lead with Potential Anticancer, CDK4 Inhibition and Selective Radiotheranostic Effect: Synthesis, 2D & 3D QSAR, Molecular Dynamics, In Vitro Cytotoxicity, Radioiodination, and Biodistribution Studies

“…Characterization and the purity determination of the new target compounds were performed by melting points determination, spectroscopic methods (IR, 1 H NMR, 13 C NMR, and mass spectra) in addition to elemental analysis. Compound 3-acetyl-6-bromo-2 H -chromen-2-one ( 1 ) was obtained by a Knoevenagel condensation reaction when 6-bromo salicylaldehyde was allowed to react with ethyl acetoacetate in the presence of few drops of piperidine according to the reported method [ 50 , 51 , 52 , 53 ]. Furthermore, the intermediates 2-(1-(6-bromo-2-oxo-2 H -chromen-3-yl)ethylidene)- N -methyl (phenyl) hydrazine-1-carbothioamide 2a,b were prepared by the reaction of 1 with N -methyl (phenyl)hydrazine-1-carbothioamide in absolute ethyl alcohol acidified with a catalytic amount of acetic acid in accordance to the documented method [ 54 , 55 , 56 ].…”

“…Synthesis of 2-bromo-1-(1H-benzo[d]imidazol-2-yl)-1-ethanone (3) was achieved according to the reported method [ 47 , 50 , 51 , 52 , 53 ].…”

Synthesis and Evaluation of Antimicrobial Activity of Some Novel Heterocyclic Compounds from 5‐Bromosalicylaldehyde

“…Due to the interesting activity of coumarins as biological agents, considerable attention has been focused on this class of heterocycles. The pharmaceutical importance of these compounds lies in the fact that they can be utilized as anti‐inflammatory , anticancer , anticoagulant , antimicrobial, and antioxidant activities . A literature survey revealed that a special attention was given to 1,3,4‐thiadiazole derivatives that proved to have promising biological activities such as antimicrobial , anticancer , antioxidant , antiamoebic , anticonvulsant , anti‐inflammatory, and analgesic activities .…”

Angupyrones A – E, α‐Pyrone Analogues with ARE‐Activation from a Sponge‐Associated Fungus Truncatella angustata

“…In addition, α ‐pyrones possess a broad array of pharmaceutical effects, while the bioactivities closely rely on the structural variation. Bufadienolides with steroid nucleus‐bearing pyrones exhibited significant inhibition against leukaemia cell lines, fusapyrones bearing a sugar moiety at C(2) of pyrones exerted antibiotic effects toward fungi, gibepyrones are a group of 6‐substitued‐3‐methyl‐2‐pyrones showed antibacterial effects, 2‐pyrones with 4‐methoxy‐5‐methyl and 6‐unsaturated alkyl chain such as herbarins A and B exhibited insecticidal activities, and peripyrones containing pyridine, 2‐pyrone, and sesquiterpene moieties displayed potent inhibition against acyl‐CoA and AChE to be potential for the treatment of Alzheimer 's disease, [ ][ ] whereas coumarins exhibited a broad array of bioactivities including anticancer, antimicrobial, antifungal, antioxidant, androgen, and HIV‐1 protease inhibitory based on the structural diversity. Accordingly, investigation of new α ‐pyrones may provide the chemical entities for new leads in the pharmaceutical usage.…”