Coumarin hybrid derivatives as promising leads to treat tuberculosis: Recent developments and critical aspects of structural design to exhibit anti-tubercular activity.

Chalcones found in fruits and vegetables have promising cancer chemopreventive properties. This study attempts to identify the anticancer efficacies of chalcone flavokawain B (FKB) in the rhizomes of Alpinia pricei Hayata by examining key molecular events in non-small-cell lung cancer (A549) cells. Our results indicated that in human A549 cells, FKB (0-15 μg/ml) decreases cell viability and colony formation, dysregulates the Bax:B-cell lymphoma 2 ratio and increases apoptotic DNA fragmentation. Mitochondrial (caspase-9/-3 and poly ADP ribose polymerase [PARP]) signaling was found to be involved in FKB-induced apoptosis. In addition, FKB-induced reactive oxygen species (ROS) generation, and N-acetylcysteine attenuated FKB-induced apoptotic cell death. Moreover, FKB triggered autophagy, as evidenced by the improved acidic vesicular organelle formation, lipidated light chain 3 (microtubule-related light chain 3) accumulation, and ATG7 expression and the decreased mammalian target of rapamycin phosphorylation. Furthermore, FKB suppressed ROS-mediated ATG4B expression. Inhibiting autophagy using 3-methyladenine/chloroquine diminished FKB-induced cell death, indicating that autophagy is triggered as a death mechanism by FKB. In summary, FKB has a crucial role in the execution and propagation of ROS-mediated apoptotic and autophagic cell death of lung adenocarcinoma cells.

Anticancer activities of chalcone flavokawain B from Alpinia pricei Hayata in human lung adenocarcinoma (A549) cells via induction of reactive oxygen species-mediated apoptotic and autophagic cell death.

Several oxidative processes are related to a wide range of human chronic and degenerative diseases, like Alzheimer’s disease, which also has been related to cholinergic processes. Therefore, search for new or improved antioxidant molecules with acetylcholinesterase activity is essential to offer alternative chemotherapeutic agents to support current drug therapies. A series of chalcone (2a–2k) and flavone (3a–3k) analogs were synthesized, characterized, and evaluated as acetylcholinesterase (AChE) inhibitors, and antioxidant agents using 1,1-diphenyl-2-picrylhydrazyl (DPPH•), 2-2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonate) (ABTS•), and β-carotene/linoleic acid bleaching assay. Compounds more active were 3j and 2k in DPPH with EC50 of 1 × 10−8 and 5.4 × 10−3 μg/mL, respectively; 2g and 3i in ABTS (1.14 × 10−2 and 1.9 × 10−3 μg/mL); 2e, 2f, 3f, 2j, and 3j exceeded the α-tocopherol control in the β-carotene assay (98–99% of antioxidant activity). At acetylcholinesterase inhibition assay, flavones were more active than chalcones; the best results were compounds 2d and 3d (IC50 21.5 and 26.8 µg/mL, respectively), suggesting that the presence of the nitro group enhances the inhibitory activity. The docking of these two structures were made to understand their interactions with the AChE receptor. Although further in vivo testing must be performed, our results represent an important step towards the identification of improved antioxidants and acetylcholinesterase inhibitors.

Synthesis, Biological Evaluation and Docking Studies of Chalcone and Flavone Analogs as Antioxidants and Acetylcholinesterase Inhibitors

Chalcones (natural or synthetic derivatives) are aromatic ketones possessing a central backbone that form a core for variety important compounds with different substitutions. Recent scientific advances show that chalcones exhibit different bio-medical activities, including antiviral, which is related to the variety substitutions. This review provides general information on the origin, sources, virucidal and direct antiviral properties of chalcones in vitro, as well as a brief overview of the possible application and molecular modes of action of these compounds. The antiviral effect of chalcones probably results from the disruption of the different stage of viral replication cycle, inhibition of viral or cell enzymes, induction of apoptosis and others. Structural requirements for antiviral activities vary according to the mechanisms of action. Based on the published information, it could be considered that synthetic chalcones are very perspective antiviral candidates and deserve further studies for elucidating of their pharmacological potential.

Antiviral properties of chalcones and their synthetic derivatives: a mini review

Chalcones are promising synthons and bioactive scaffolds of great medicinal interest due to their numerous pharmacological and biological activities. They are well recognized to possess antimicrobial, anticancer, antitubercular, antioxidant, anti-inflammatory, antileishmanial, and other significant biological activities. This chapter highlights recent updates and applications of chalcones as biologically, pharmacologically, and medicinally important entities.

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Biological Role of Chalcones in Medicinal Chemistry

Chalcone is an aromatic ketone that forms a central core for a variety of important biological compounds, which are collectively known as chalcones. They possess different activities like antibacterial, antifungal, anti-inflammatory and anti tumor etc depending on the substitution made on them. Chalcones are 1,3-diphenyl-2-propene-1-one, in which two aromatic rings are linked by a three carbon α, β-unsaturated carbonyl system.These are abundant in edible plants and are considered to be precursors of flavonoids and isoflavonoids. Chalcones possess conjugated double bonds and a completely delocalized Π-electron system on both benzene rings. Molecules possessing such system have relatively low redox potentials and have a greater probability of undergoing electron transfer reactions. The compounds with the backbone of chalcones have been reported to possess various biological activities such as antimicrobial, anti-inflammatory, analgesic, anti platelet, anti ulcerative, anti malarial, anticancer, antiviral, anti leishmanial, antioxidant, anti tubercular, anti hyperglycemic, immunomodulatory, inhibition of chemical mediators release, inhibition of leukotriene B4, inhibition of tyrosinase and inhibition of aldose reductase activities. The presence of a reactive alpha, beta -unsatutated keto function in chalcones is found to be responsible for their antimicrobial activity. In this paper through reviewing different biological significance of chalcones and their derivatives have been reported along with their chemistry and of synthesis. Synthetically or chemically chalcones are synthesized by two reactions: a) Aldol condensation and b) Claisen Schmidt condensation. But here is a focus on chalcones synthesized by Claisen Schmidt condensation which involves the condensation between an aromatic aldehyde or ketone with an aliphatic ketone or aldehyde catalysed by the presence of dilute alkali or acid to form alpha beta unsaturated compound.

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Mehta Pp

Papers

Synthesis and Medicinal Significance of Chalcones- A Review