Synthesis and antibacterial activity of novel chalcone derivatives bearing a coumarin moiety

Insights into chalcone analogues with potential as antioxidant additives in diesel-biodiesel blends

Biodiesel production is one of the promising strategies to reduce diesel consumption and an important contribution to climate change. However, biodiesel stability remains a challenging problem in biofuel use in the global energy matrix. In this context, organic additives have been investigated to minimize these problems and reduce harmful emissions to comply with fuel requirement standards. In this study, we discuss a comprehensive structural description, a behavior of B15 [85% volume of diesel and 15% volume of biodiesel (B100)] stability in the presence of antioxidants (chalcone analogues), and a theoretical calculation to pave the way for clarifying and expanding the potential of title compounds as an antioxidant additive for diesel-biodiesel blends. Finally, a systematic description of the oxidation stability was undertaken using a specialized machine learning computational pySIRC platform.

Crystal structure of ethyl (Z)-3-amino-2-cyano-3-(2-oxo-2H-chromen-3-yl)acrylate, C15H12N2O4

C15H12N2O4, monoclinic, P21/c (no. 14), a = 5.4588(5) Å, b = 29.629(3) Å, c = 8.1217(8) Å, β = 93.157(1)°, V = 1311.6(2) Å3, Z = 4, R gt (F) = 0.0346, wR ref (F 2) = 0.0925, T = 296(2) K.

Synthesis and Evaluation of Coumarin-Chalcone Derivatives as α-Glucosidase Inhibitors

Coumarin and chalcone, two important kinds of natural product skeletons, both exhibit α-glucosidase inhibitory activity. In this work, coumarin-chalcone derivatives 3 (a∼v) were synthesized, and their α-glucosidase inhibitory activity was screened. The results showed that all synthetic derivatives (IC50: 24.09 ± 2.36 to 125.26 ± 1.18 μM) presented better α-glucosidase inhibitory activity than the parent compounds 3-acetylcoumarin (IC50: 1.5 × 105 μM) and the positive control acarbose (IC50: 259.90 ± 1.06 μM). Among them, compound 3t displayed the highest α-glucosidase inhibitory activity (IC50: 24.09 ± 2.36 μM), which was approximately 10 times stronger than that of acarbose. The kinetic assay of 3t (KI = 18.82 μM, KIS = 59.99 μM) revealed that these compounds inhibited α-glucosidase in a mixed-type manner. Molecular docking was used to simulate the interaction between α-glucosidase and compound 3t.

Crystal structure of 3-acetyl-6-hydroxy-2H-chromen-2-one monohydrate, C11H10O5

[C11H10O5], monoclinic, P21/n, a = 7.041(3) Å, b = 9.339(4) Å, c = 15.614(6) Å, β = 103.03°, V = 1000.2(7) Å3, Z = 4, Rgt (F) = 0.0337, wR ref (F 2) = 0.0994, T = 296(2) K.

Crystal structure of 6-methyl-3-(pyrrolidine-1-carbonyl)-2H-chromen-2-one, C15H15N1O3

C15H15N1O3, triclinic, P 1 ‾ $P\overline{1}$ (no. 2), a = 7.1053(11) Å, b = 8.3014(12) Å, c = 11.0297(16) Å, α = 85.810(2)°, β = 79.896(2)°, γ = 87.055(2)°, V = 638.28(16) Å3, Z = 2, R gt (F) = 0.0371, wR ref (F 2) = 0.1062, T = 296(2) K.

Coumarin-containing hybrids and their antibacterial activities

Infections caused by Gram-positive and -negative bacteria are one of the foremost causes of morbidity and mortality globally. Antibiotics are the mainstay of therapy for bacterial infections, but the emergence and wide spread of drug-resistant pathogens have already become a huge issue for public healthcare systems. The coumarin moiety, which is ubiquitous in nature, could bind to the B subunit of DNA gyrase in bacteria and inhibit DNA supercoiling by blocking the ATPase activity; hence, coumarin derivatives possess potential antibacterial activity. Several coumarin-containing hybrids such as coumermycin A1, clorobiocin, and novobiocin have already been used in clinical practice for the treatment of various bacterial infections; thus, it is conceivable that hybridization of the coumarin moiety with other antibacterial pharmacophores may provide opportunities for the development of novel antibiotics. This review outlines the advances in coumarin-containing hybrids with antibacterial potential in the recent 5 years and the structure-activity relationships are also discussed.