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Nicotinamide adenine dinucleotide phosphate oxidase 4 (NOX4) has emerged as a promising target for developing drugs to tackle renal fibrosis. In this study, a series of chromone derivatives were designed and synthesized. Additionally, we established a NOX4 overexpression model using the NRK-49F rat renal fibroblasts cell line and identified compound 14m as highly active through the assessment of intracellular reactive oxygen species (ROS) levels in this model. The drug affinity responsive target stability (DARTS) assay illuminated the robust binding stability of 14m with NOX4. Mechanistic studies further substantiated its efficacy in ameliorating fibrosis and inflammation. This investigation positions 14m as a noteworthy NOX4 inhibitor, shedding light on its regulatory role in renal fibroblasts. Importantly, it diversifies the structural landscape of NOX4 inhibitors, offering novel lead compounds for future development., (© 2024 John Wiley & Sons Ltd.)

Despite the enormous importance of chromone and flavonoid piperidine alkaloids, a general method for their synthesis has not been described. Accordingly, from simple tetrahydro-3-pyridinemethanols ( A ) and phenol derivatives ( B ), a synthetic approach to chromone and flavonoid piperidine alkaloids is presented. The access to a novel chromone and flavonoid alkaloid precursors 4-(2-hydroxyphenyl)-3-methylenepiperidines ( C ) is achieved in only two steps: Mitsunobu reaction followed by an intramolecular C-H phenolization via an aromatic Claisen rearrangement of the respective Mitsunobu adducts ( D ). Consequently, the simultaneous installation of the functionalized phenol group and the exo-methylene group within the piperidine skeleton, permits, not only the easy construction of the chromone or flavonoid cores but also the simultaneous installation of the hydroxyl group with the required cis -orientation. Additionally, the synthetic utility of this novel approach is showcased in the formal synthesis of flavopiridol, rohitukine, and their N -Moc analogues.

Chalaniline A, an aminofulveno[1,2- b ]chromone derivative previously isolated from a vorinostat-treated ascomycete Chalara sp., was prepared in nine steps from orcinol (3,5-dihydroxytoluene). In a key transformation, the tricyclic ring system of the target was generated by a pyrrolidine-catalyzed double annulation between α-(methylsulfinyl)-2,6-dihydroxy-4-methylacetophenone and the ketaldoester, methyl 2,5-dioxopentanoate. The resulting tertiary alcohol (coniochaetone H) was further converted to chalaniline A by operations including dehydration (to yield a hydroxyfulvene), Vilsmeier reaction, and enamine exchange.

Overexpression of Bcl-2 protein is a predominant hallmark of disturbed apoptotic pathway in most of the cancers. Herein, chromone-linked thiazolidinediones were designed and synthesized to target Bcl-2 for regulating anti-apoptotic proteins. The study on in vitro cancer cell lines revealed the presence of compounds 8a, 8k, 8l, and 8n, which were found to have good to moderate anti-proliferative activity (with an IC 50 concentration less than 10 µM). Among them, 8l depicted the highest cytotoxicity on the A549 cell line with an IC 50 of 6.1 ± 0.02 µM. Aberrantly, the compounds displayed less toxicity towards human embryonic kidney HEK cells underlining its selectivity. The DCFDA study revealed a gradual increase in the ROS generation of 8l, followed by its quantification by flow analysis. Similarly, the studies including DAPI, AO/EtBr and Annexin-V binding clearly elucidated the DNA damage, membrane integrity prospects, and insights for early and late apoptotic phases. Markedly, the Bcl-2-FITC anti-body study revealed that compound 8l reduced the expression of anti-apoptotic proteins by 79.1 % compared to the control at 9 µM concentration. In addition, the molecular docking study provided the impending scope of these hybrids, showing promising interaction with the Mcl-1 target (member of the Bcl-2 family) with comparable binding affinities., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Previously, we documented the synthesis and assessed the biological effects of chalcones containing selenium against HT-29 human colorectal adenocarcinoma cells, demonstrating their significant potential. As research on selenium-containing flavonoids remains limited, this article outlines our design and synthesis of three selenium-based flavonols and three 2-styrylchromones. We conducted evaluations of these compounds to determine their impact on human lung cancer cells (A549, H1975, CL1-0, and CL1-5) and their influence on normal lung fibroblast MRC5 cells. Additionally, we included selenium-based chalcones in our testing for comparative purposes. Our findings highlight that the simplest compound, designated as compound 1, exhibited the most promising performance among the tested molecules., (© 2024 Deutsche Pharmazeutische Gesellschaft.)

2-Alkyl chromanone scaffold has become prominent in pharmaceuticals and natural compounds. Consequently, devising robust strategies for synthesizing 2-alkyl chromanones remains crucial. Here, multicomponent reactions were employed to synthesize 2-alkyl chromanones containing an oxazole moiety using 3-formylchromones, amines, and N -propargylamides as reactants. This method utilizes readily available feedstocks with a catalytic amount of Zn(OTf) 2 and exhibits an impressive substrate scope compared to existing methods. Importantly, the synthesized compounds demonstrated highly selective anticancer activity against the DU145 cell line.

Aim: Chromones are promising for anticancer drug development. Methods & results: 12 chromone-based compounds were synthesized and tested against cancer cell lines. Compound 8 showed the highest cytotoxicity (LC 50 3.2 μM) against colorectal cancer cells, surpassing 5-fluorouracil (LC 50 4.2 μM). It suppressed colony formation, induced cell cycle arrest and triggered apoptotic cell death, confirmed by staining and apoptosis markers. Cell death was accompanied by enhanced reactive oxygen species formation and modulation of the autophagic machinery (autophagy marker light chain 3B (LC3B); adenosine monophosphate-activated protein kinase (AMPK); protein kinase B (PKB); UNC-51-like kinase (ULK)-1; and ULK2). Molecular docking and dynamic simulations revealed that compound 8 directly binds to ULK1. Conclusion: Compound 8 is a promising lead for autophagy-modulating anti-colon cancer drugs.

Chromone-based compounds have established cytotoxic, antiproliferative, antimetastatic, and antiangiogenic effects on various cancer cell types via modulating different molecular targets. Herein, 17 novel chromone-2-carboxamide derivatives were synthesized and evaluated for their in vitro anticancer activity against 15 human cancer cell lines. Among the tested cell lines, MDA-MB-231, the triple-negative breast cancer cell line, was found to be the most sensitive, where the N-(2-furylmethylene) (15) and the α-methylated N-benzyl (17) derivatives demonstrated the highest growth inhibition with GI 50 values of 14.8 and 17.1 μM, respectively. In vitro mechanistic studies confirmed the significant roles of compounds 15 and 17 in the induction of apoptosis and suppression of EGFR, FGFR3, and VEGF protein levels in MDA-MB-231 cancer cells. Moreover, compound 15 exerted cell cycle arrest at both the G0-G1 and G2-M phases. The in vivo efficacy of compound 15 as an antitumor agent was further investigated in female mice bearing Solid Ehrlich Carcinoma. Notably, administration of compound 15 resulted in a marked decrease in both tumor weight and volume, accompanied by improvements in biochemical, hematological, histological, and immunohistochemical parameters that verified the repression of both angiogenesis and inflammation as additional Anticancer mechanisms. Moreover, the binding interactions of compounds 15 and 17 within the binding sites of all three target receptors (EGFR, FGFR3, and VEGF) were clearly illustrated using molecular docking., (© 2024 Wiley Periodicals LLC.)

Diabetes is a serious metabolic disorder affecting individuals of all age groups and prevails globally due to the failure of previous treatments. This study aims to address the most prevalent form of type 2 diabetes mellitus (T2DM) by reporting on the design, synthesis, and in vitro as well as in silico evaluation of chromone-based thiosemicarbazones as potential α-glucosidase inhibitors. In vitro experiments showed that the tested compounds were significantly more potent than the standard acarbose, with the lead compound 3n exhibiting an IC 50 value of 0.40 ± 0.02 μM, ~2183-fold higher than acarbose having an IC 50 of 873.34 ± 1.67 μM. A kinetic mechanism analysis demonstrated that compound 3n exhibited reversible inhibition of α-glucosidase. To gain deeper insights, in silico molecular docking, pharmacokinetics, and molecular dynamics simulations were conducted for the investigation of the interactions, orientation, stability, and conformation of the synthesized compounds within the active pocket of α-glucosidase., (© 2024 Deutsche Pharmazeutische Gesellschaft.)

A mechanistic study was performed within the molecular electron density theory at the B3LYP/6-311G (d,p) computational level to explain the regioselectivity observed. An electron localization function analysis was also performed, and the results confirm the zwitterionic-type (zw-type) mechanism of the cycloaddition reactions between nitrile oxide and alkylated 4 H -chromene-2-carboxylate derivatives and shed more light on the obtained regioselectivity experimentally. In silico studies on the pharmacokinetics, ADME and toxicity tests of the compounds were also performed, and it was projected that compounds 5a , 5b , 5c and 5d are pharmacokinetic and have favorable ADME profiles. Moreover, docking and molecular dynamics investigations were conducted to evaluate the interactions, orientation and conformation of the target compounds on the active sites of four distinct enzymes. The results of this investigation showed that two compounds, 5a and 5c , interacted effectively with the S. aureus active site while maintaining acceptable binding energy.Communicated by Ramaswamy H. Sarma.

A series of chromone-deferiprone hybrids were designed, synthesized, and evaluated as inhibitors of human monoamine oxidase B ( h MAO-B) with iron-chelating activity for the treatment of Alzheimer's disease (AD). The majority exhibited moderate inhibitory activity towards h MAO-B and potent iron-chelating properties. Particularly, compound 25c demonstrated remarkable selectivity against h MAO-B with an IC 50 value of 1.58 μM and potent iron-chelating ability (pFe 3+ = 18.79) comparable to that of deferiprone (pFe 3+ = 17.90). Molecular modeling and kinetic studies showed that 25c functions as a non-competitive h MAO-B inhibitor. According to the predicted results, compound 25c can penetrate the blood-brain barrier (BBB). Additionally, it has been proved to display significant antioxidant activity and the ability to inhibit neuronal ferroptosis. More importantly, compound 25c reduced the cognitive impairment induced by scopolamine and showed significant non-toxicity in short-term toxicity assays. In summary, compound 25c was identified as a potential anti-AD agent with h MAO-B inhibitory, iron-chelating and anti-ferroptosis activities.

The chromenopyridine scaffold represents an important class of heterocyclic compounds exhibiting a broad spectrum of biological properties. This review describes novel and efficient procedures for the synthesis of this scaffold. Herein, several methods were detailed and grouped according to their starting material (e.g., salicylaldehydes, chromones, chromanones and coumarins) and respective biological activity, when reported. This review highlights the potential of the reported synthetic strategies for preparing chromenopyridine derivatives with promising biological activity, paving the way for further developments in drug discovery.

Herein, we present an efficient Pd-catalysed method for stereoselective synthesis of chromone C -glycosides from various glycals. We successfully applied this method to various glycals with different protecting groups, yielding the corresponding glycosides in 41-78% yields. Additionally, we investigated the potential of this approach for the late-stage modification of natural products and pharmaceutical compounds linked to glycals, leading to the synthesis of their respective glycosides. Furthermore, we extended our research to gram-scale synthesis and demonstrated its applicability in producing various valuable products, including 2-deoxy-chromone C -glycosides. In summary, our work introduces a novel library of chromone glycosides, which holds promise for advancing drug discovery efforts.

A series of novel chromone derivatives of (N-(4-oxo-2-(trifluoromethyl)-4H-chromen-6-yl) benzamides) were synthesized by treating 7-amino-2-(trifluoromethyl)-4H-chromen-4-one with K 2 CO 3  and/or NaH, suitable alkyl halides and acetonitrile and/or 1,4-dioxane. The obtained products are in high yields (87 to 96%) with various substituents in short reaction times with no more by-products and confirmed by FT-IR,  1 H, and  13 C-NMR Spectral data. The in vitro cytotoxic activity was examined against two human cancer cell lines, namely the human lung adenocarcinoma (A-549) and the human breast (MCF-7) cancer cell line. Compound 4h showed promising cytotoxicity against both cell lines with IC 50  values of 22.09 and 6.40 ± 0.26 µg/mL respectively, compared to that of the standard drug. We also performed the in vitro antioxidant activity by DPPH radical, hydrogen peroxide, NO scavenging, and total antioxidant capacity (TAC) assay methods, and they showed significant activities. The possible binding interactions of all the synthesized chromone derivatives are also investigated against selective pharmacological targets of human beings, such as HERA protein for cytotoxic activity and Peroxiredoxins (3MNG) for antioxidant activity which showed closer binding free energies than the standard drugs and evidencing the above two types of activities., (© 2024. The Author(s).)

In consideration of the chromones' therapeutic potential and anticancer activity, a new series of chromanone derivatives have been synthesized through a straightforward reaction between 6-formyl-7-hydroxy-5-methoxy-2-methylchromone (2) and various organic active compounds. The cytotoxic activity of the newly synthesized congeners was investigated against MCF-7 (human breast cancer), HCT-116 (colon cancer), HepG2 (liver cancer), and normal skin fibroblast cells (BJ1). The obtained data indicated that compounds 14b, 17, and 19 induce cytotoxic activity in the breast MCF7, while compounds 6a, 6b, 11 and 14c showed highly potent activity in the colon cancer cell lines. Overall, the results demonstrate that the potential cytotoxic effects of the studied compounds may be based on their ability to induce DNA fragmentation in cancer cell lines, down-regulate the expression level of CDK4 as well as the anti-apoptotic gene Bcl-2 and up-regulate the expression of the pro-apoptotic genes P53 and Bax. Furthermore, compounds 14b and 14c showed a dual mechanism of action by inducing apoptosis and cell cycle arrest. The docking studies showed that the binding affinity of the most active cytotoxic compounds within the active pocket of the CDK4 enzyme is stronger due to hydrophobic and H-bonding interactions. These results were found to be consistent with the experimental results., (© 2024. The Author(s).)

Introduction: A series of 15 thiazolyl hydrazone derivatives of chromone-3- carbaldehyde have been designed and synthesized by the cyclization of thiosemicarbazone derivatives of chromone-3-carbaldehydes with 4'-substituted-2-bromo acetophenones., Methods: All these derivatives were evaluated for antioxidant activity by their direct scavenging activity objects to reactive oxygen species such as DPPH, and nitric oxide, as well as in vitro antiinflammatory activity by a protein denaturation method. Most of these synthesized compounds have shown significant antioxidant activity, among which the compounds 5b, 5c, 5e, 5g, and 5j showed very good antioxidant activities in comparison with the standard ascorbic acid. The in vitro anti-inflammatory activity revealed that the compounds 5b, 5g, and 5h possessed significant activity compared to standard diclofenac sodium., Results: Additionally, molecular docking studies of these molecules using ovalbumin as the protein showed remarkable interactions with its active site residues, and the results indicated that the binding mode of these compounds closely resembled that of the reference compound, diclofenac sodium., Conclusion: Thus, these compounds represent an attractive template for the evaluation of new antiinflammatory and antioxidant agents and might be useful for exploring new therapeutic tools., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Based on a multitarget strategy, a series of novel chromanone-1-benzyl-1,2,3,6-tetrahydropyridin hybrids were identified for the potential treatment of Alzheimer's disease (AD). Biological evaluation demonstrated that these hybrids exhibited significant inhibitory activities toward acetylcholinesterase (AChE) and monoamine oxidase B (MAO-B). The optimal compound C10 possessed excellent dual AChE/MAO-B inhibition both in terms of potency and equilibrium (AChE: IC 50 = 0.58 ± 0.05 μM; MAO-B: IC 50 = 0.41 ± 0.04 μM). Further molecular modeling and kinetic investigations revealed that compound C10 was a dual-binding inhibitor bound to both the catalytic anionic site and peripheral anionic site of AChE. In addition, compound C10 exhibited low neurotoxicity and potently inhibited AChE enzymatic activity. Furthermore, compound C10 more effectively protected against mitochondrial dysfunction and oxidation than donepezil, strongly inhibited AChE-induced amyloid aggregation, and moderately reduced glutaraldehyde-induced phosphorylation of tau protein in SH-SY5Y cells. Moreover, compound C10 displayed largely enhanced improvements in cognitive behaviors and spatial memory in a scopolamine-induced AD mice model with better efficacy than donepezil. Overall, the multifunctional profiles of compound C10 suggest that it deserves further investigation as a promising lead for the prospective treatment of AD.

This article describes a part of the results obtained from the cooperation between the University of Lyon1 (France) and the University of Antananarivo (Madagascar). It shows (among others) that useful research can be carried out in developing countries of the tropics if their social, technical, and economic conditions are taken into account. The concepts and methods associated with so-called "green chemistry" are particularly appropriated for this purpose. To illustrate this approach, two examples are shown. The first deals with industrial ecology and concerns waste transformation from the production of cashew nut into an amphiphilic product, oxyacetic derivatives. This product was obtained with a high yield and in a single step reaction. It exhibited an important surfactant property similar to those of the main fossil-based ones but with a much lower ecological impact. The second talks about chemical ecology as an alternative to insecticides and used to control dangerous mosquito populations. New substituted chromones were synthesized and showed biological activities toward Aedes albopictus mosquito species. Strong repellent properties were recorded for some alkoxylated products if others had a significant attractant effect (Kairomone) depending on their stereochemistry and the length of the alkyl chain.

A number of chromone derivatives containing sulfonamide structure were designed and synthesized. Firstly, the target compounds were evaluated for anti-TSWV activities in vivo by the half-leaf method. We found that most of the compounds had good anti-TSWV activities. Among them, compound 12B had excellent anti-TSWV inactivating activity with an EC 50 of 80.5 μg/mL, which was significantly better than xiangcaoliusuobingmi (765.7 μg/mL). Secondly, TSWV nucleocapsid protein (N) was expressed and purified, and the affinity between the compounds and TSWV N was tested by microscale thermophoresis (MST). Compound 12B had a good affinity for TSWV N with a K d value of 5.02 μM, which was superior to xiangcaoliusuobingmi (29.83 μM). Finally, in order to study the mode of interaction between the compound 12B and TSWV N, we carried out molecular docking. The results indicated that compound 12B might inactivate the virus by destroying the TSWV N oligomer structure. These results lay a solid foundation for the further discovery of chromone derivatives containing sulfonamide structure with high anti-TSWV activities., (Copyright © 2021. Published by Elsevier Ltd.)

Based on previous studies, 66 2-phenyl-4H-chromone derivatives containing amide and 1,3,4-oxadiazole moieties were prepared as potential telomerase inhibitors. The results showed most of the title compounds exhibited significantly inhibitory activity on telomerase. Among them, some compounds demonstrated the most potent telomerase inhibitory activity (IC 50 < 1 µM), which was significantly superior to the staurosporine (IC 50 = 6.41 µM). In addition, clear structure-activity relationships were summarised, indicating that the substitution of the methoxy group and the position, type and number of the substituents on the phenyl ring had significant effects on telomerase activity. Among them, compound A33 showed considerable inhibition against telomerase. Flow cytometric analysis showed that compound A33 could arrest MGC-803 cell cycle at G2/M phase and induce apoptosis in a concentration-dependent way. Meanwhile, Western blotting revealed that this compound could reduce the expression of dyskerin, which is a fragment of telomerase.

Dirchromone is a bioactive vinyl sulfoxide-bearing chromone first isolated from the shrub Dirca palustris . Altogether, 32 of its derivatives were prepared to assess the effect of substitution of its chromone core upon activities against cancer cell lines, Gram-positive bacteria, and fungi (such as Candida albicans ). All compounds were synthesized following a synthetic strategy involving Pummerer and soft-enolization Baker-Venkataraman rearrangements. Substituent position changes induced little variability on the activities tested. There was no correlation between cytotoxic and antibacterial effects, suggesting different underlying mechanisms of action. In particular, hydroxy group and cyanide substituents diminished cytotoxicity, with the latter featuring enhanced antibacterial activity. Higher homologues of 6-alkoxydirchromones also exhibited progressively emerging antifungal activity. Other modifications had moderate effects on cytotoxicity with some derivatives leading to increased potency. This behavior highlights the robustness of the natural dirchromone pharmacophore toward decoration, thus paving the way for more elaborate future drug design.

American trypanosomiasis (Chagas disease) caused by the Trypanosoma cruzi parasite, is a severe health problem in different regions of Latin America and is currently reported to be spreading to Europe, North America, Japan, and Australia, due to the migration of populations from South and Central America. At present, there is no vaccine available and chemotherapeutic options are reduced to nifurtimox and benznidazole. Therefore, the discovery of new molecules is urgently needed to initiate the drug development process. Some acetophenones and chalcones, as well as chromane-type substances, such as chromones and flavones, are natural products that have been studied as trypanocides, but the relationships between structure and activity are not yet fully understood. In this work, 26 compounds were synthesized to determine the effect of hydroxyl and isoprenyl substituents on trypanocide activity. One of the compounds showed interesting activity against a resistant strain of T. cruzi , with a half effective concentration of 18.3 µM ± 1.1 and an index of selectivity > 10.9.

Microwave irradiation has become a popular heating technique in organic synthesis, mainly due to its short reaction times, solventless reactions, and, sometimes, higher yields. Additionally, microwave irradiation lowers energy consumption and, consequently, is ideal for optimization processes. Moreover, there is evidence that microwave irradiation can improve the regioselectivity and stereoselectivity aspects of vital importance in synthesizing bioactive compounds. These crucial features of microwave irradiation contribute to its inclusion in green chemistry procedures. Since 2003, the use of microwave-assisted organic synthesis has become common in our laboratory, making our group one of the first Portuguese research groups to implement this heating source in organic synthesis. Our achievements in the transformation of heterocyclic compounds, such as ( E / Z )-3-styryl-4 H -chromen-4-ones, ( E )-3-(2-hydroxyphenyl)-4-styryl-1 H -pyrazole, ( E )-2-(4-arylbut-1-en-3-yn-1-yl)-4 H -chromen-4-ones, or ( E )-2-[2-(5-aryl-2-methyl-2 H -1,2,3-triazol-4-yl)vinyl]-4 H -chromen-4-ones, will be discussed in this review, highlighting the benefits of microwave irradiation use in organic synthesis.

A new biological scaffold was produced by replacing the 6π-electron phenyl ring-B of a natural flavone skeleton with a 10π-electron benzothiophene (BT). Since aromatic rings are important for ligand protein interactions, this expansion of the π-electron system of ring-B might change the bioactivity profile. One of the resulting novel natural product-inspired compounds, 2-(benzo[b]thiophen-3-yl)-5-hydroxy-7-isopropoxy-6-methoxyflavone (6), effectively arrested the cell cycle at the G2/M phase and displayed significant antiproliferative effects with IC 50 values of 0.05-0.08 μM against multiple human tumor cell lines, including a multidrug resistant line. A structure-activity relationship study revealed that a 10π-electron system with high aromaticity, juxtaposed 4-oxo and 5-hydroxy groups, and 7-alkoxy groups were important for potent antimitotic activity. Interestingly, two BT-flavonols (3-hydroxyflavone), 16 and 20, with 3-hydroxy and 5-alkoxy groups, induced distinct biological profiles affecting the cell cycle at the G1/S phase by inhibition of DNA replication through an interaction with topoisomerase I., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021. Published by Elsevier Masson SAS.)

Herein we report an enantioselective method for the rapid construction of chiral 3-nitro-4-chromanones via a chiral thiourea-catalyzed intramolecular Michael-type cyclization reaction. With this method, a series of 3,3-disubstituted-3-nitro-4-chromanones bearing contiguous C2/C3 stereocenters were obtained with high diastereoselectivities and good to excellent enantioselectivities. In vitro biological evaluations indicated that the chiral amide derivative of the product showed more potent antitumor activities than both the racemic and the corresponding enantiomers, showcasing the high influence of enantioselective methodology development toward medicinal studies.

AD is one of the most typical neurodegenerative disorders that suffer many seniors worldwide. Recently, MAO inhibitors have received increasing attention not only for their roles involved in monoamine neurotransmitters metabolism and oxidative stress but also for their additional neuroprotective and neurorescue effects against AD. The curiosity in MAO inhibitors is reviving, and novel MAO-B inhibitors recently developed with ancillary activities (e.g., Aβ aggregation and AChE inhibition, anti-ROS and chelating activities) have been proposed as multitarget drugs foreshadowing a positive outlook for the treatment of AD. The current review describes the recent development of the design, synthesis, and screening of multifunctional ligands based on MAO-B inhibition for AD therapy. Structure-activity relationships and rational design strategies of the synthetic or natural product derivatives (chalcones, coumarins, chromones, and homoisoflavonoids) are discussed., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Chromone-3-phenylcarboxamides ( Crom-1 and Crom-2 ) were identified as potent, selective, and reversible inhibitors of human monoamine oxidase B ( h MAO-B). Since they exhibit some absorption, distribution, metabolism, and excretion (ADME)-toxicity liabilities, new derivatives were synthesized to map the chemical structural features that compose the pharmacophore, a process vital for lead optimization. Structure-activity relationship data, supported by molecular docking studies, provided a rationale for the contribution of the heterocycle's rigidity, the carbonyl group, and the benzopyran heteroatom for h MAO-B inhibitory activity. From the study, N -(3-chlorophenyl)-4 H -thiochromone-3-carboxamide ( 31 ) ( h MAO-B IC 50 = 1.52 ± 0.15 nM) emerged as a reversible tight binding inhibitor with an improved pharmacological profile. In in vitro ADME-toxicity studies, compound 31 showed a safe cytotoxicity profile in Caco-2, SH-SY5Y, HUVEC, HEK-293, and MCF-7 cells, did not present cardiotoxic effects, and did not affect P-gp transport activity. Compound 31 also protected SH-SY5Y cells from iron(III)-induced damage. Collectively, these studies highlighted compound 31 as the first-in-class and a suitable candidate for in vivo preclinical investigation.

Chromones represent a privileged scaffold in medicinal chemistry and are an omnipresent structural motif in natural products. Chemically encoded non-natural peptidomimetics feature improved stability towards enzymatic degradation, cell permeability and binding affinity, translating into a considerable impact on pharmaceutical industry. Herein, a strategy for the sustainable assembly of chromones via electro-formyl C-H activation is presented. The rational design of the rhodaelectro-catalysis is guided by detailed mechanistic insights and provides versatile access to tyrosine-based fluorogenic peptidomimetics., (© 2021. The Author(s).)

Herein we report the synthesis of some new 1 H -1,2,4-triazole functionalized chromenols ( 3a - 3n ) via tandem reactions of 1-(alkyl/aryl)-2-(1 H -1,2,4-triazole-1-yl) with salicylic aldehydes and the evaluation of their antifungal activity. In silico prediction of biological activity with computer program PASS indicate that the compounds have a high novelty compared to the known antifungal agents. We did not find any close analog among the over 580,000 pharmaceutical agents in the Cortellis Drug Discovery Intelligence database at the similarity cutoff of 70%. The evaluation of antifungal activity in vitro revealed that the highest activity was exhibited by compound 3k , followed by 3n . Their MIC values for different fungi were 22.1-184.2 and 71.3-199.8 µM, respectively. Twelve from fourteen tested compounds were more active than the reference drugs ketoconazole and bifonazole. The most sensitive fungus appeared to be Trichoderma viride , while Aspergillus fumigatus was the most resistant one. It was found that the presence of the 2-( tert -butyl)-2 H -chromen-2-ol substituent on the 4th position of the triazole ring is very beneficial for antifungal activity. Molecular docking studies on C. albicans sterol 14α-demethylase (CYP51) and DNA topoisomerase IV were used to predict the mechanism of antifungal activities. According to the docking results, the inhibition of CYP51 is a putative mechanism of antifungal activity of the novel chromenol derivatives. We also showed that most active compounds have a low cytotoxicity, which allows us to consider them promising antifungal agents for the subsequent testing activity in in vivo assays.

A series of 3-styrylchromone derivatives was synthesized and evaluated for monoamine oxidase (MAO) A and B inhibitory activities. Most of all derivatives inhibited MAO-B selectively, except compound 21. Compound 19, which had a methoxy group at R 2 on the chromone ring and chlorine at R 4 on phenyl ring, potently inhibited MAO-B, with an IC 50 value of 2.2 nM. Compound 1 showed the highest MAO-B selectivity, with a selectivity index of >3700. Further analysis of these compounds indicated that compounds 1 and 19 were reversible and mixed-type MAO-B inhibitors, suggesting that their mode of action may be through tight-binding inhibition to MAO-B. Quantitative structure-activity relationship (QSAR) analyses of the 3-styrylchromone derivatives were conducted using their pIC 50 values, through Molecular Operating Environment (MOE) and Dragon. There were 1796 descriptors of MAO-B inhibitory activity, which showed significant correlations (P < 0.05). Further investigation of the 3-styrylchromone structures as useful scaffolds was performed through three-dimensional-QSAR studies using AutoGPA, which is based on the molecular field analysis algorithm using MOE. The MAO-B inhibitory activity model constructed using pIC 50 value index exhibited a determination coefficients (R 2 ) of 0.972 and a Leave-One-Out cross-validated determination coefficients (Q 2 ) of 0.914. These data suggest that the 3-styrylchromone derivatives assessed herein may be suitable for the design and development of novel MAO inhibitors., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The success of cancer chemotherapy is limited by multidrug resistance (MDR), which is mainly caused by P-glycoprotein (P-gp) overexpression. In the present study, we describe a novel microtubule inhibitor, 5-(N-methylmaleimid-3-yl)-chromone (SPC-160002), that can be used to overcome MDR. A synthetic chromone derivative, SPC-160002, showed a broad spectrum of anti-proliferative effects on various human cancer cells without affecting P-gp expression and its drug efflux function. Treatment with SPC-160002 arrested the cell cycle at the M phase, as evidenced using fluorescence-activated cell sorting analysis, and increased the levels of mitotic marker proteins, including cyclin B, pS10-H3, and chromosomal passenger complex. This mitotic arrest by SPC-160002 was mediated by promoting and stabilizing microtubule polymerization, similar to the mechanism observed in case of taxane-based drugs. Furthermore, SPC-160002 suppressed the growth and sphere-forming activity of cancer stem cells. Our data herein strongly suggest that SPC-160002, a novel microtubule inhibitor, can be used to overcome MDR and can serve as an attractive candidate for anticancer drugs.

A series of novel N-substituted α-aminophosphonates-bearing chromone moiety were synthesized and evaluated for acetylcholinesterase (AChE), butyrylcholinesterase (BuChE) activities and antioxidant properties. Porcine pancreatic lipase was employed as a catalyst. Inhibitory activity against AChE ranged between 0.103 and 5.781 µM, whereas for BuChE, activities ranged between 8.619 and 18.789 µM. The results show that among the various synthesized compounds, strongest AChE inhibition was found for the compound containing aliphatic amine analogs, while in case of BuChE, aromatic amines showed better activity as compared to aliphatic amines. Compound 4j was found to be the most potent inhibitor of AChE with an IC 50 value of 0.103 ± 0.24 μM and inhibited AChE through mixed-type inhibition. Compound 4j was twofolds more potent than tacrine, 35-folds potent than galantamine and 50-folds potent than rivastigmine. Also, docking study revealed that compound 4j binds to both the peripheral anionic site and catalytic anionic site of AChE and BuChE. The antioxidant activities of synthesized compounds were performed against 2,2-diphenyl-1-picrylhydrazyl and hydrogen peroxide scavenging. DNA nicking activity of selected compounds also suggested that the compounds do not harm plasmid DNA pBR322. Compound 4j also showed significant DNA damage protection activity. Novel N-substituted α-aminophosphonates bearing chromone moiety were synthesized and evaluated for anti-acetylcholinesterase, anti-butyrylcholinesterase, antioxidant and DNA damage activities.

A new serise of 7-hydroxy-chromone derivatives bearing pyridine moiety were synthesized, and evaluated as multifunctional agents against Alzheimer's disease (AD). Most of the compounds were good AChE inhibitors (IC 50  = 9.8-0.71 µM) and showed remarkable BuChE inhibition activity (IC 50  = 1.9-0.006 µM) compared with donepezil as the standard drug (IC 50  = 0.023 and 3.4 µM). Compounds 14 and 10 showed the best inhibitory activity toward AChE (IC 50  = 0.71 µM) and BuChE (IC 50  = 0.006 µM), respectively. The ligand-protein docking simulations and kinetic studies revealed that compound 14 and 10 could bind effectively to the peripheral anionic binding site (PAS) of the AChE and BuChE through mixed-type inhibition. In addition, the most potent compounds showed acceptable neuroprotective activity on H 2 O 2 - and Aβ-induced .neurotoxicity in PC12 cells, more than standard drugs. The compounds could block effectively self- and AChE-induced Aβ aggregation. All the results suggest that compounds 14 and 10 could be considered as promising multi-target-directed ligands against AD., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Prospective antiviral molecule (2E)-N-methyl-2-[(4-oxo-4H-chromen-3-yl)methylidene]-hydrazinecarbothioamide has been probed using Fourier transform infrared (FTIR), FT-Raman and quantum chemical computations. The geometry equilibrium and natural bond orbital analysis have been carried out with density functional theory employing Becke, 3-parameter, Lee-Yang-Parr method with the 6-311G++(d,p) basis set. The vibrational assignments pertaining to different modes of vibrations have been augmented by normal coordinate analysis, force constant and potential energy distributions. Drug likeness and oral activity have been carried out based on Lipinski's rule of five. The inhibiting potency of 2(2E)-methyl-2-[(4-oxo-4H-chromen-3-yl)methylidene]-hydrazinecarbothioamide has been investigated by docking simulation against SARS-CoV-2 protein. The optimized geometry shows a planar structure between the chromone and the side chain. Differences in the geometries due to the substitution of the electronegative atom and intermolecular contacts due to the chromone and hydrazinecarbothioamide were analyzed. NBO analysis confirms the presence of two strong stable hydrogen bonded NH⋯O intermolecular interactions and two weak hydrogen bonded CH⋯O interactions. The red shift in NH stretching frequency exposed from IR substantiates the formation of NH⋯O intermolecular hydrogen bond and the blue shift in CH stretching frequency substantiates the formation of CH⋯O intermolecular hydrogen bond. Drug likeness, absorption, distribution, metabolism, excretion and toxicity property gives an idea about the pharmacokinetic properties of the title molecule. The binding energy of the nonbonding interaction with Histidine 41 and Cysteine 145, present a clear view that 2(2E)-methyl-2-[(4-oxo-4H-chromen-3-yl)methylidene]-hydrazinecarbothioamide can irreversibly interact with SARS-CoV-2 protease., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020. Published by Elsevier B.V.)

Within this work, we describe the design and synthesis of a range of novel thiochromanones based on natural products reported to possess anti-leishmanial action, and their synthetic derivatives. All compounds were elaborated via the key intermediate 2,2,6-trimethoxythiochromanone, which was modified at the benzylic position to afford various ester, amine and amide analogues, substituted by chains of varying lipophilicity. Upon testing in Leishmania , IC 50 values revealed the most potent compounds to be phenylalkenyl and haloalkyl amides 11a and 11e , with IC 50 values of 10.5 and 7.2 μM, respectively.

The present study describes the discovery of novel inhibitors of mushroom tyrosinase enzyme. For that purpose, a series of varyingly substituted 2-phenylchromone analogues 1-28 were synthesized and characterized in detail by various spectroscopic techniques (UV-Vis, FTIR, 1 H NMR, 13 C NMR) and mass spectrometry. All the derivatives (1-28) were screened in vitro for their inhibitory potential against mushroom tyrosinase enzyme. Interestingly, all the synthetic compounds displayed good to excellent inhibitory activity with IC 50 values ranging from 0.093 ± 0.003 μg/ml to 23.58 ± 0.94 μg/ml for brominated 3-hydroxy-2-phenylchromones and 0.22 ± 0.017 μg/ml to 22.22 ± 1.1 μg/ml for brominated 2-phenylchromones against tyrosinase in comparison to the standard kojic acid (IC 50  = 1.79 ± 0.64 μg/ml). Remarkably, the bromine atoms attached on ring A attribute to increases the inhibitory potential of 2-phenylchromone moiety and anti-tyrosinase assay demonstrated that compound 10 (IC 50  = 0.093 ± 0.003 µg/ml) was found almost nineteenfold, 11 (IC 50  = 0.126 ± 0.015 µg/ml) fourteenfold and 26 (IC 50  = 0.22 ± 0.017 µg/ml) about eightfold more active than the positive control. Notably, among the already literature reported tyrosinase inhibitors, these analogues have been found the most active inhibitors of mushroom tyrosinase with the lowest possible IC 50 values. To design and develop novel tyrosinase inhibitors using 2-phenylchromone as a structural motif in the future, a limited structure-activity relationship was established. Moreover, in silico studies were carried out to rationalize the binding mode of interactions of all the targeted compounds (1-28) with the active site of enzymes. The experimental and theoretical results are in parallel with one another. In addition, molecular description was performed with the drug-likeness and bioactivity scores. Computational analysis predicted that few compounds are in a linear correlation with Lipinski's RO5 indicating superb drug-likeness and bioactivity score for drug targets., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Over activation of neutrophils has been linked to many inflammatory diseases; one of critical pathologic mechanisms is that generation and exocellular release of superoxide anion from neutrophils results in peripheral tissues damage. Besides, in this study, 2-(3,5-dimethoxyphenoxy)-5,7-dimethoxy-chromen-4-one (4), a 2-phexnoychromone from our compound bank, was demonstrated to have the moderate inhibitory effect on superoxide anion generating. Therefore, serial chromones substituted with phenols or 3-flourothiophenol were designed, synthesized, and examined for suppression of superoxide anion generation. In accordance with the results, the methoxy group at 7 position (R 3 ) of the chromone, as well as a hydrogen bond donor at a meta site of the phenyl ring greatly impacted on the activity. 2-(3-fluorophenyl)sulfanyl-7-methoxy-chromen-4-one (16), a successful example of bioisosteres from a phenol to a thiophenol, exhibited prominent anti-inflammatory effects with the IC 50 value against superoxide anion generation of 5.0 ± 1.4 μM., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Background: Previous and recent scientific research has shown that triazolopyrimidine and furochromones have a wide range of pharmacological activities for the treatment of numerous diseases, including anticancer, antiviral, anti-depressant, anti-microbial, anti-inflammatory, and analgesic activities., Objective: Preparation of new drugs derived from a natural furochromones as (1-hydrazinyl or methylthio),-furopyrimidoquinazolinone, 1, 2, 4-triazolopyrimidofuroquinazolin-5-one, and quinazoline- pyrimidofuro- quinazoline-8, 10-dione and the study of their biological activity as antimicrobial agents., Methods: A series of novel N'-furopyrimidoquinazoline-hydrazide; 1, 2, 4-triazolopyrimidofuroquinazolin- 5-one; furopyrimidoquinazolin-3-one and quinazoline-pyrimidofuroquinazoline-8, 10- dione derivatives were synthesized from substituted (methylthio)-furopyrimidoquinazolinone (3ab) and 1-hydrazinyl-furopyrimido- quinazolinone (4a-b) as the starting material., Results: All compounds were synthesized in good yields (71-95%) in a gradually efficient system under mild condition and some of the procedures were used such as microwave oven. The new compounds have been confirmed by means of different spectroscopic methods such as IR, 1D and 2D -NMR techniques and mass spectrum. The in vitro antimicrobial activities were evaluated for the prepared compounds using many types of bacteria (Gram-positive and Gram-negative) and fungi., Conclusion: 1, 2, 4-triazolopyrimidofuroquinazolin-5-one derivatives (10a-f, 8a-b, 7a-b and 6a-d) showed the most efficient antimicrobial activities compared with the cefotaxime sodium and nystatin as standard drugs., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Analogs of dirchromone were prepared to shed light on the pivotal role of its peculiar vinylsulfoxide side chain towards its cytotoxic and antimicrobial properties, especially dependant upon the presence and oxidation state of sulfur. The reaction of dirchromone with cysteamine revealed a surprising Michael acceptor behavior with elimination of the methylsulfinyl moiety and redox transformation of the sulfur atom that could be involved in the mode of action of dirchromone within cells.

Metal complexes have numerous applications in the current era, particularly in the field of pharmaceutical chemistry and catalysis. A novel synthetic approach for the same is always a beneficial addition to the literature. Henceforth, for the first time, we report the formation of three new Pd(II) complexes through the Michael addition pathway. Three chromone-based thiosemicarbazone ligands (SVSL1-SVSL3) and Pd(II) complexes ( 1 - 3 ) were synthesized and characterized by analytical and spectroscopic tools. The Michael addition pathway for the formation of complexes was confirmed by spectroscopic studies. Distorted square planar structure of complex 2 was confirmed by single-crystal X-ray diffraction. Complexes 1 - 3 were subjected to DNA- and BSA-binding studies. The complex with cyclohexyl substituent on the terminal N of thiosemicarbazone ( 3 ) showed the highest binding efficacy toward these biomolecules, which was further understood through molecular docking studies. The anticancer potential of these complexes was studied preliminarily by using MTT assay in cancer and normal cell lines along with the benchmark drugs (cisplatin, carboplatin, and gemcitabine). It was found that complex 3 was highly toxic toward MDA-MB-231 and AsPC-1 cancer cells with IC 50 values of 0.5 and 0.9 μM, respectively, and was more efficient than the standard drugs. The programmed cell death mechanism of the complexes in MDA-MB-231 cancer cells was confirmed. Furthermore, the complexes induced apoptosis via ROS-mediated mitochondrial signaling pathway. Conveniently, all the complexes showed less toxicity (≥50 μM) against MCF-10a normal cell line. Molecular docking studies were performed with VEGFR2, EGFR, and SARS-CoV-2 main protease to illustrate the binding efficiency of the complexes with these receptors. To our surprise, binding potential of the complexes with SARS-CoV-2 main protease was higher than that with chloroquine and hydroxychloroquine.

A series of furoxan derivatives of chromone were prepared. The antiproliferative activities were tested against five cancer cell lines HepG2, MCF-7, HCT-116, B16, and K562, and two normal human cell lines L-02 and PBMCs. Among them, compound 15a exhibited the most potent antiproliferative activity. It was also found 15a produced more than 8 µM of NO at the peak time of 45 min by Griess assay. Generally, antiproliferative activity is positively related to NO release to some extent. Further in-depth studies on apoptosis-related mechanisms showed that 15a caused S-phase cell cycle arrest in a concentration-dependent manner and induced apoptosis significantly through mitochondria-related pathways. Human apoptosis protein array assay also demonstrated 15a increased the expression levels of pro-apoptotic Bax, Bad, HtrA2 and Trail R2/DR5. The expression of catalase and cell cycle blocker claspin were similarly up-regulated. In balance, 15a induced K562 cells death through both endogenous and exogenous pathways.

In this study, a series of novel 7H-benzo [c] [1,3] dioxolo [4, 5-f] chromen-7-one derivatives were obtained by structural modification of the lead compounds with Fissitungfine B. A total 15 compounds were designed, synthesized and evaluated as inhibitors of tumor. These target compounds have the novel chemical structures that named three six-membered rings including one lactone six-membered ring. In vitro assay, the results showed that the target compounds have a broad spectrum and strong of anti-tumor activity. Such as the target compound 4n to MCF-7 was IC 50  = 0.35 ± 0.01 μM, to A-549 was IC 50  = 0.37 ± 0.01 μM, to Hela was IC 50  = 0.56 ± 0.02 μM, to MDC-803 was IC 50  = 0.53 ± 0.02 μM and COLO-205 was IC 50  = 0.50 ± 0.02 μM in vitro. At the same time, in vivo anti-tumor activity assay results showed that the target compounds had a good inhibitory effect on tumor growth. Among them, the target compound 4n had the best anti-tumor activity, it could inhibit tumor growth well at a low dose. The target compound 4n could be used as a candidate drug for further research and development, in order to be used as early as application in the clinical treatment of tumors., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Antagonists for the serotonin receptor 2B (5-HT 2B ) have clinical applications towards migraine, anxiety, irritable bowl syndrome, and MDMA abuse; however, few selective 5-HT 2B antagonists have been identified. Previous studies from these labs identified a natural product, 5-hydroxy-2-(2-phenylethyl)chromone (5-HPEC, 2) as the first non-nitrogenous ligand for the 5-HT 2B receptor. Studies on 5-HPEC optimization led to the identification of 5-hydroxy-2-(3-phenylpropyl)chromone (5-HPPC, 3), which showed a tenfold improvement in binding affinity over 2 at 5-HT 2B . This study aimed to further improve receptor pharmacology of this unique scaffold. Guided by molecular modeling studies modifications at the C-3' and C-4' positions of 3 were made to probe their effects on ligand binding affinity and efficacy. Among the derivatives synthesized 5-hydroxy-2-(3-(3-cyanophenyl)propyl)chromone (5-HCPC, 3d) showed the most promise with a multifold improvement in binding affinity (pK i  = 7.1 ± 0.07) over 3 with retained antagonism., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Infections caused by pathogenic bacteria, especially the drug-resistant bacteria, are posing a devastating threat to public health, which underscores the urgent needs for advanced strategies to effectively prevent and treat these intractable issues. Here we report a feasible and effective theranostic platform based on an enzyme-sensitive and photoactivatable carbon monoxide releasing molecule (CORM-Ac) for the successive detection and elimination of bacterial infection. The extracellular bacterial lipase can trigger the excited state intramolecular proton transfer (ESIPT) via elimination of the ester group in CORM-Ac, thus providing a fluorescence switch for an early warning of infection. Subsequently, the potent bactericidal therapy against the model bacterial strains, Staphylococcus aureus (S. aureus) and notorious methicillin-resistant Staphylococcus aureus (MRSA), was readily realized via photoinduced release of CO. In addition, the CORM-Ac and CORM showed good biocompatibility within a wide range of concentrations. The results of an infected animal wound test also demonstrated that the CORM-Ac-loaded gauze was effective in indicating the wound infection and accelerating the wound healing via the photoinduced CO release. The simplicity, functional integration, good biocompatibility and broad adaptability make CORM-Ac very attractive for bacterial theranostic applications.

A number of 1,2,3,4-tetrahydrochromeno[3,2-c]pyridin-10-one derivatives have been synthesized and screened against different targets involved in the onset and progression of Alzheimer's disease (AD), such as acetyl- and butyrylcholinesterase (AChE and BChE), monoamine oxidases A and B (MAO A and B), aggregation of β-amyloid (Aβ) and reactive oxygen species (ROS) production. Derivatives 1 c, 3 b, 4 and 5 a showed multifaceted profiles of promising anti-AD features and returned well-balanced multitargeting inhibitory activities. Moreover, compound 1 f, a potent and selective human MAO B inhibitor (IC 50 =0.89 μM), proved to be a safe neuroprotectant in a human neuroblastoma cell line (SH-SY5Y) by improving viability impaired by Aβ 1-42 and pro-oxidant insult. Furthermore, structure-activity relationships (SARs) and docking models were derived in order to assist further hit-to-lead optimization stage., (© 2020 Wiley-VCH GmbH.)

Thirty-four seco-3'R,4'R-disubstituted-2',2'-dimethyldihydropyrano[2,3-f]chromone (seco-DSP) derivatives were designed, synthesized and evaluated for chemo-reversal activity when combined with paclitaxel or vincristine in P-gp overexpressing A2780/T and KB-VIN drug-resistant cancer cell lines. Most of the compounds displayed moderate to significant MDR reversal activities. Compound 7e showed the most potent chemo-sensitization activity with more than 1471 reversal ratio at a concentration of 10 μM, which was higher than verapamil (VRP) (212-fold). Unexpectedly the newly synthesized compounds did not show chemosensitization activities in a non-P-gp overexpressing cisplatin resistant human ovarian cancer cell line (A2780/CDDP), implying that the MDR reversal effects might be associated with P-gp overexpression. Moreover, the compounds did not exhibit significant anti-proliferative activities against non-tumorigenic cell lines (HUVEC, HOSEC and T29) compared to VRP at the tested concentration and might be safer than VRP. In preliminary pharmacological mechanism studies, the compounds increased accumulation of DOX and promoted P-gp ATPase activity in A2780/T cell lines. Western blot analysis indicated they did not affect the expression level of P-gp in the tested MDR cell lines. Thus, further studies on these seco-DSP derivatives are merited with the goal of developing a desirable chemosensitizer drug candidate., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Masson SAS. All rights reserved.)

The Breast Cancer Resistance Protein (BCRP/ABCG2) belongs to the G class of ABC (ATP-Binding Cassette) proteins, which is known as one of the main transporters involved in the multidrug resistance (MDR) phenotype that confer resistance to anticancer drugs. The aim of this study was to design, synthesize and develop new potent and selective inhibitors of BCRP that can be used to abolish MDR and potentialize clinically used anticancer agents. In previous reports, we showed the importance of chromone scaffold and hydrophobicity for the inhibition of ABC transporters. In the present study we report the design and development of chromones linked to one or two amino acids residues that are either hydrophobic or found in the structure of FTC, one of most potent (but highly toxic) inhibitors of BCRP. Herewith, we report the synthesis and evaluation of 13 compounds. The studied molecules were found to be not toxic and showed strong inhibition activity as well as high selectivity toward BCRP. The highest activity was obtained with the chromone bearing a valine residue (9c) which showed an inhibition activity against BCRP of 50 nM. The rationalization of the inhibition potential of the most active derivatives was performed through docking studies. Taken together, the ease of synthesis and the biological profile of these compounds render them as promising candidates for further development in the field of anticancer therapy., Competing Interests: Declaration of competing interest The authors declare no conflicts of interest regarding the publication of this manuscript., (Copyright © 2020 Elsevier Masson SAS. All rights reserved.)

Macrophages, with diverse functions and variable phenotypes, are considered as an important executor of inflammatory diseases. And it has been proved that autophagy is deeply connected with the development of inflammation, while the exact regulatory mechanism still remains unclear, and the application of autophagy regulators in anti-inflammation needs to be further confirmed. Here, we firstly verified that neochromine S5 (hereinafter referred to as S5) significantly inhibited M1-like macrophage polarization with decrease of the proinflammatory cytokines and downregulation of NF-κB and STAT1 signals. Then, in vivo experiments demonstrated S5 improved cecal ligation and puncture (CLP)-induced sepsis specially based on the regulation of M1-like macrophages. Mechanistic studies indicated that S5 treatment dramatically upregulated cellular autophagy in M1-like macrophage. Furthermore, by multiple methods, S5 was revealed to directly bind with ubiquitin-specific proteases 14 (USP14) at Ser404, Phe405, and Cys414 by hydrogen bond to inhibit its deubiquitinating activity, and block USP14-TRAF6 (TNF receptor associated factor 6) interaction, subsequently promoting ubiquitination of Beclin1, interrupting Beclin1-Bcl2 interaction, and accumulating the autophagosome in macrophages, which finally resulted in the blockade of M1-like macrophage polarization. Animal experiments also confirmed the protection of S5 in CLP mice was dependent on activation of macrophage autophagy. What's more, as a novel USP14 inhibitor, S5 exhibited higher efficiency and safety than IU1, the known USP14 inhibitor. Therefore, this study has demonstrated that typically inhibiting USP14 promotes autophagy in M1-like macrophages and alleviates CLP-induced sepsis. Moreover, we provide a new candidate compound, S5, for sensitizing autophagy to interfere with the macrophage inflammation.

An enantioselective total synthesis of the natural product (-)-preussochromone A is reported. The tricyclic thiopyrane skeleton could be assembled via Lewis acid-mediated cycloisomerization of a precursor with a 2-thiochromenone substructure and an α-ketoester moiety. The chromenone core was synthesized by cyclization of a dithioketene acetal and oxidation to a 2-sulfonylchromenone to set up the subsequent thia-Michael- retro -Michael addition of an aliphatic thiol producing the highly oxidized side chain.

A novel series of hybrid arylisoxazole-chromenone carboxamides were designed, synthesized, and evaluated for their cholinesterase (ChE) inhibitory activity based on the modified Ellman's method. Among synthesized compounds, 5-(3-nitrophenyl)-N-{4-[(2-oxo-2H-1-benzopyran-7-yl)oxy]phenyl}-1,2-oxazole-3-carboxamide depicted the most acetylcholinesterase (AChE) inhibitory activity (IC 50 =1.23 μm) and 5-(3-chlorophenyl)-N-{4-[(2-oxo-2H-1-benzopyran-7-yl)oxy]phenyl}-1,2-oxazole-3-carboxamide was found to be the most potent butyrylcholinesterase (BChE) inhibitor (IC 50 =9.71 μm). 5-(3-Nitrophenyl)-N-{4-[(2-oxo-2H-1-benzopyran-7-yl)oxy]phenyl}-1,2-oxazole-3-carboxamide was further investigated for its BACE1 inhibitory activity as well as neuroprotectivity and metal chelating ability as important factors involved in onset and progress of Alzheimer's disease. It could inhibit BACE1 by 48.46 % at 50 μm. It also showed 6.4 % protection at 25 μm and satisfactory chelating ability toward Zn 2+ , Fe 2+ , and Cu 2+ ions. Docking studies of 5-(3-nitrophenyl)-N-{4-[(2-oxo-2H-1-benzopyran-7-yl)oxy]phenyl}-1,2-oxazole-3-carboxamide and 5-(3-chlorophenyl)-N-{4-[(2-oxo-2H-1-benzopyran-7-yl)oxy]phenyl}-1,2-oxazole-3-carboxamide confirmed desired interactions with those amino acid residues of the AChE and BChE, respectively., (© 2020 Wiley-VHCA AG, Zurich, Switzerland.)