Chromone Moiety Research Articles

Preparation, physicochemical, anticancer, and theoretical studies of mono‐ and bi‐nuclear Ni(II), Co(II), and Cd(II) complexes containing chromone moiety

Preparation, physicochemical, anticancer, and theoretical studies of mono‐ and bi‐nuclear Ni(II), Co(II), and Cd(II) complexes containing chromone moiety

Chromone hybrids as interleukin-6 and acetylcholinesterase inhibitor for treatment of Alzheimer's disease: Design, docking, synthesis and evaluation

The course of Alzheimer's disease (AD) is largely influenced by interleukin-6 (IL-6) and acetylcholinesterase (AChE). Therefore, concurrent suppression of these two targets is a rational approach for the development of anti-AD molecules. The study is aimed to design a molecule with pharmacophore capable of inhibiting both the targets. Four series are designed by coupling a chromone moiety (a pharmacophore that inhibits IL-6) with a N,N-disubstituted amine (that inhibits AChE) through a linker (1–4 carbon chain). The in silico studies on the designed compounds led to the identification of 16 best-fit compounds having good oral bioavailability and blood brain barrier permeability. All 16 compounds were synthesized and evaluated for anti-AChE activity. Six compounds showing >45 % inhibition of AChE at 1 μM concentration are further evaluated for BuChE (butyrylcholinesterase) and IL-6 inhibitory activities. Compound YS3g is the most potent inhibitor of EeAChE (IC50 = 0.45 μM) and of IL-6 (IC50 = 0.46 μM). Subsequently, it is found to show dose-dependent effects in STZ (streptozotocin)-induced memory deficit model at three doses (0.2, 0.4 and 0.8 mg/kg). At higher dose (0.8 mg/kg), it reverses the deficit as also supported by histopathological studies. The findings reveal that a chromone nucleus coupled with a piperazine via a three-carbon linker may be a useful template for developing novel moieties against AD.

Synthesis, structural characterization, fukui functions, DFT calculations, molecular docking and biological efficiency of some novel heterocyclic systems

The electron deficient centers in α,β-unsaturated ketone 3 are C-2 and C=O of chromone moieties as well as C=O and H-β of α,β-unsaturated ketone segment. To investigate the reactivity of various electron deficient centers and to synthesize some heterocyclic systems, compound 3 was allowed to react with some binucleophilic reagents. The antimicrobial activity of some compounds showed a notable inhibitory effect on the microorganisms that were being studied. The synthesized compounds were verified by spectral and analytical data. The structure of the prepared compounds were optimized at the DFT/B3LYP level of theory employing 6-311G(d,p). Density Functional Theory (DFT) was used to compute the chemical reactivity descriptors. Compound 9 is more stable and less reactive than other compounds. MEP mapping was applied at the same computational level to identify the favored locations for electrophilic and nucleophilic assault, providing additional insight into the regioselectivity in the desired reaction. Moreover, the most reactive sites of compound 3 were investigated by Fukui function descriptor using Mulliken charges. The 13C and 1H-NMR spectra of the prepared compound were measured experimentally in DMSO, and correlated with the theoretical calculations that performed by 6-311G(d,p) of DFT-B3LYP method. All compounds met Veber's and Lipinski's requirements according to in silico predictions made with the SwissADME online server, suggesting the possibility for usage as oral active drugs. The synthesized compounds were also subjected to molecular docking studies to investigate their binding pattern and affinity for the CDKs active site and correlated with antimicrobial data.

Domino reactions of chromones with activated carbonyl compounds.

Domino reactions of chromones with activated carbonyl compounds, such as dimethyl acetone-1,3-dicarboxylate and 1,3-diphenylacetone, and with 1,3-bis(silyloxy)-1,3-butadienes, electroneutral equivalents of 1,3-dicarbonyl dianions, allow for a convenient synthesis of a great variety of products. The regioselectivity and course of the reaction depends of the substituent located at carbon C3 of the chromone moiety and also on the type of nucleophile employed.

Novel annulated chromeno[3',2':5,6]pyrido[2,3-d][1,3,4]thiadiazolo[3,2-a] pyrimidines and chromeno[3'',2'':5',6']pyrido[2',3':4,5]pyrimido[2,1-b][1,3,4] thiadiazines: Synthetic approaches and antimicrobial efficiency

The current study includes synthetic approaches for some linear heterocyclic compounds containing chromone moiety. Chromenopyridopyrimidine bearing amino-thione functions 4 was efficiently synthesized starting from 6,8-dimethylchromone-3-carbonitrile (1). The novel chromenopyridothiadiazolopyrimidines were synthesized through condensation of the key precursor 4 with some mono-electrophilic reagents. In addition, heteroannulated chromenopyridopyrimidothiadiazines were synthesized through condensation of compound 4 with some α-halogenated carbonyl reagents. The synthesized products were examined for their antimicrobial efficiency appearing remarkable activity against the inspected microorganisms especially compounds 7, 12 and 14. The synthesized products were inferred using analytical and spectral data.

Unveiling of novel synthesized coumarin derivative for efficient self-driven hybrid organic/inorganic photodetector applications

During this study, a novel organic semiconductor material comprising coumarin and chromone moieties was synthesized via a facile route. Thin films of the synthesized powder were thermally deposited under vacuum conditions. The structural and morphological properties were investigated using X-ray diffraction and scanning electron microscope techniques, respectively. With increasing the film thickness, a relative crystallinity enhancement was observed, besides improving the surface features and uniformity. Furthermore, the UV–vis–NIR spectral transmittance and reflectance of the grown films were measured. The variation of film thickness induced significant changes in the optical parameters either dispersive or electronic such as energy gap (3.67–3.8 eV), oscillator energy (4.25–4.56 eV), and dispersion energy (4.61–10.31 eV). In addition, the nonlinear optical parameters and PL emission spectra of the prepared films were measured and analyzed in detail. Then, these films were exploited integrally with p-Si for the fabrication hybrid junction for light sensing. The optimized film thickness based on the optical, structure results, and electronic performance under dark conditions was ∼124 nm. Such a device showed a pronounced self-driven photodetection performance under different illumination intensities. The photoelectronic parameters including responsivity (∼5.17 mA/W), detectivity (∼2.64 × 1010 Jones), linearity (∼72.72 dB), and rise/fall times(∼51.48 ms/47.75 ms) were extracted and compared to other organic/p-Si devices and showed a high superiority.

2-Styrylchromones as inhibitors of α-amylase and α-glucosidase enzymes for the management of type 2 diabetes mellitus

α-amylase and α-glucosidase are key enzymes implicated in carbohydrate digestion and their inhibition has been suggested as a powerful approach for regulating blood glucose levels. The present work describes for the first time their inhibition by a group of twelve hydroxylated 2-styrylchromones (2-SC). Our findings revealed that 2-SC display strong systematic inhibition of α-glucosidase rather than α-amylase activity. The number and position of the hydroxy groups in the chromone moiety further modulate the inhibitory profile of the studied compounds, and the derivatives bearing one catechol unit are efficient inhibitors of both enzymes. Enzyme kinetic studies indicate that all active compounds act as competitive inhibitors of α-amylase while most of them behave as non-competitive inhibitors of α-glucosidase. The results are promising and pave the way to further deciphering the potential of this class of compounds as a suitable alternative for the management of type 2 diabetes and its complications.

Nucleophilic reactions with the novel 7-(chromon-3-yl)quinolino [3′,4′:5,6] pyrano[3,2-c]quinoline: Synthesis, biological and computational studies

Condensation reaction of 3-formylchromone (1) with 1-ethyl-4-hydroxyquinolin-2(1H)-one (2) in glacial acetic acid afforded the condensation product 4; in 1:2 molar ratio. Compound 4 was used as precursor for construction of some propenones linked pentacyclic quinolinopyranoquinoline. Ring opening of chromone moiety in compound 4 was achieved via reactions with a diversity of primary amines leading to propenone derivatives 5–7 and 11–13 in good yields (62–73%). All propanone derivatives exist in the E-configuration as deduced from their 1H NMR spectra. DFT/B3LYP functional was used with 6–311+G(d,p) basis sets for all theoretical calculations. Based on optimized geometry, the chemical potential (Pi), electronegativity (χ), hardness (η) and electrophilicity index (ω) are some of the global reactivity descriptors that were computed to predict the chemical reactivity of the studied compounds; where compound 13 has the highest softness and electrophilicity index (ω). Moreover, to determine the relative stability of compounds 1–4, the thermodynamic parameters such as enthalpy and free energies of the reactions were computed; where compound 4 has the lowest free energy of reaction (-439.61 kcal/mol), so its formation is spontaneous. By utilizing molecular electrostatic potential (MEP) and local-based descriptors in the form of condensed Fukui functions of the starting compound 4, the susceptible sites for electrophilic and nucleophilic attack were investigated. For compound 4, fk+ and Δfk values are more positive at C9 and C7 than other sites and these sites have more electrophilic characters. Therefore, nucleophilic attacks began at C9. On the other hand, the GIAO approximation was used to compute the 1H and 13C NMR chemical shift values in the ground state, of the present compounds, where a good agreement was observed between experimental and theoretical chemical shift results. Further, the calculated first hyperpolarizability of prepared compounds are found to be greater than that of urea. So, these compounds are ideal candidates for non-linear optical applications. The synthesized compounds were screened for their antimicrobial and anticancer activities showing variable inhibitory action. Compounds 5, 7 and 13 were more effective antimicrobial candidates against all tested microorganisms, while compound 13 was the most active against HepG-2 cell lines. Furthermore, a quantitative structure–activity relationship (QSAR) (relationship between DFT calculated descriptors and biological activities pIC50) model was built by applying multiple linear regression (MLR) on the synthesized compounds as anticancer agents. Moreover, Lipinski's rule of five indicates no problems with oral bioavailability of the prepared compounds.

Rational repurposing, synthesis, in vitro and in silico studies of chromone-peptidyl hybrids as potential agents against Leishmania donovani

A chromone-peptidyl hybrids series was synthesised and rationally repurposed towards identification of potential antileishmanial hits against visceral leishmaniasis. Three hybrids 7c, 7n, and 7h showed potential IC50 values (9.8, 10, and 12 µM, respectively) which were comparable to erufosine IC50 (9.8 µM) but lower potency than miltefosine IC50 (3.5 µM). Preliminary assessment of cytotoxicity using human THP-1 cells presented chromone-peptidyl hybrids 7c and 7n as non-cytotoxic up to 100 µM while erufosine and miltefosine had CC50 of 19.4 µM and >40 µM, respectively. In silico studies pinpointed the N-p-methoxyphenethyl substituent at the peptidyl moiety together with the oxygen-based substituted functions of the phenyl ring of the chromone moiety as crucial players in binding to LdCALP. Together, these findings present chromone-peptidyl hybrids 7c and 7n as potential and anticipated non-cytotoxic antileishmanial hit compounds for possible development of potential antileishmanial agents against visceral leishmaniasis.

Chemical reactivity of 3-substituted-6,8-dimethylchromones towards 1H-benzimidazol-2-ylacetonitrile and 5-amino-2,4-dihydro-3H-pyrazol-3-one: Spectroscopic, theoretical and in silico ADME studies

The reactivity of 1H-benzimidazol-2-ylacetonitrile and 5-amino-2,4-dihydro-3H-pyrazol-3-one, as nucleophilic reagents, was examined towards some 3-substituted-6,8-dimethylchromones 2a-d. A diversity of novel pyrido[1,2-a]benzimidazoles, chromeno[2,3-b]pyridines, pyrazolo[3,4-b]pyridines and chromenopyrazolopyridines was efficiently synthesized through different chemical transformations; depending on the functional group present at C-3 position of the chromone moiety. With B3LYP/6–311 G(d,p) basis set in the ground state, density functional theory (DFT) is used to determine the molecular geometry of synthesized compounds. The reactivity of the current compounds was studied by global reactivity descriptors at the same level of theory. In order to forecast the reactive locations on the starting substrates 2a-d for nucleophilic and electrophilic attacks, Fukui functions (local reactivity descriptors) were computed at the same level of theory. On the other hand, molecular electrostatic potential (MEP) surface maps were used to identify the nucleophilic and electrophilic sites. Moreover, 1H and 13C NMR chemical shift values in the ground state was calculated using the Gauge-Including Atomic Orbital (GIAO) technique, and the predicted values were compared with the experimental results. To interpret the nonlinear optical (NLO) property of the synthesized compounds, the dipole moment, polarizability, and first hyperpolarizability values have been measured (in the range β = 0.38 × 1030 - 3.28 × 10−30 esu). First hyperpolarizabilities of the investigated compounds indicate promising candidates for nonlinear optical applications. Also, using web-based platforms, in silico ADME calculations were performed.

Design, docking, synthesis and biological evaluation of chromone derivatives as dual inhibitors of Interleukin‐6 and acetylcholinesterase for treatment of Alzheimer’s Disease

AbstractBackgroundInterleukin‐6 (IL‐6) and acetylcholinesterase (AChE) are two important targets implicated in the progression of Alzheimer’s Disease (AD). Concurrent inhibition of both IL‐6 and AChE by a molecule presents an effective strategy for the treatment of AD. In the present study, novel molecules are designed by coupling a chromone and a N,N‐disubstituted carbamoyl amine as pharmacophore for IL‐6 and AChE inhibition, respectively.MethodFour series (S1‐S4) of 40 compounds are designed by coupling the two selected pharmacophore through alkyl linkers of different lengths (1‐4 carbon atoms). All designed compounds are docked in AChE (PDB 1EVE). The compounds having docking score ±20% of donepezil (the lead molecule) are synthesised, and evaluated for AChE inhibitory activity. The compounds showing >45% inhibition of AChE are further evaluated for IL‐6 inhibitory activity.ResultTwelve best‐fit compounds (AChE docking score >8.3) among all designed compounds are selected for synthesis. The data suggests that a 1‐ or 2‐carbon atom(s) linker is conducive to orient the pharmacophore for optimum binding with AChE active site. The predicted ADME properties of the 12 selected compounds suggest that these can cross the blood brain barrier with good oral bioavailability. These compounds are synthesised and evaluated for anti‐AChE activity. Five compounds, showing >45% inhibition of AChE, are further evaluated for IL‐6 inhibitory activity. Compound S1f is found to be the most potent inhibitor of both AChE and IL‐6 (IC50 0.7 and 0.8 µM, respectively).ConclusionA chromone moiety connected to a piperidine ring through a 1‐carbon atom linker may prove as a useful template for the development of new chemical entities effective against AD.

Revisited synthesis of fused diazepines from 3-(3-aryl-3-oxopropenyl)chromen-4-ones and binucleophilic amino enones in a three-step domino process

The synthesis of tetracyclic 11,12,13,14b-tetrahydrodi-benzo[b, f]pyrido[1,2-d][1,4]diazepines was revisited via a catalyst-free three-step domino reaction involving a pyrone ring-opening/aza-Michael addition/intramolecular cyclization, the reactants having been o-arylenediamine–dimedone adducts and 3-(3-aryl-3-oxopropenyl)chromen-4-ones. The 3-positioned exocyclic α,β-enone fragment on the chromone moiety is involved in the cyclization into the final products at the last step of the process.

Synthesis, spectral characterization, DFT and in silico ADME studies of the novel pyrido[1,2-a]benzimidazoles and pyrazolo[3,4-b]pyridines

The chemical behavior of 3-substituted-6,8-dimethylchromones 1-3 was studied towards two selected nucleophiles namely 1H-benzimidazol-2-ylacetonitrile (R1) and 5-amino-2,4-dihydro-3H-pyrazol-3-one (R2). A diversity of pyrido[1,2-a] benzimidazoles and pyrazolo[3,4-b]pyridines was efficiently synthesized through different transformation reactions; depending on the functional group present at C-3 position of the chromone moiety. The two nucleophiles reacted with acrylonitrile 1 through γ-pyrone ring opening at C-2 position followed by recyclization, while compounds 2 and 3 reacted with the two nucleophiles through addition onto the exocyclic double bonds followed by cycloaddition onto the nitrile functions. All theoretical computations were calculated by using Density Functional Theory (DFT) B3LYP method with the help of 6-311G(d,p) basis set. In theoretical studies, the global chemical activity descriptors (FMOs, electron affinity, ionization potential, hardness, softness, etc.) and MEP were calculated to predict the important information related with the stability and reactivity of the prepared molecules. Compound 7 which obtained through ring opening and recyclization of compound 1 by reagent R2 is the more stable product. Fukui functions (FFs) for the starting substrates 1-3 were determined by using the same level of theory. With the aid of local based descriptors in the form of condensed Fukui functions, the sites available for nucleophilic attack for compound 1 were C10 then at C8, and for compounds 2 and 3 were C14 then at C26. The electrons transfer occurs from the nucleophilic reagents (R1 and R2) to the starting substrates 1-3 as deduced from electrophilicity-based charge transfer study (ECT > 0). To explain the nonlinear optical (NLO) properties of the synthesized compounds, the dipole moment, polarizability, and first hyperpolarizability values (in the range 0.84 × 10−30 - 3.85 × 10−30 esu) have been calculated and compared with urea as a reference material. In addition, the 1H NMR chemical shifts of prepared compounds were simulated by GIAO manner and compared with experimental chemical shifts results. The “drug-likeness” and ADME appeared in good agreement with the Lipinski, Ghose and Veber rules, indicating the ability of the prepared compounds to be predictively orally active and bioavailable.

Discovery and evaluation of cytisine N-isoflavones as novel EGFR/HER2 dual inhibitors

Aberrant signaling of EGFR (ErbB) family members, in particular epidermal growth factor receptor (EGFR) and human epidermal growth factor 2 (HER2), is associated with the occurrence and development of many types of human malignancies (e.g., breast, lung, and gastric cancers), and dual targeting of EGFR/HER2 by small-molecular inhibitors has proven to be an effective therapeutic approach for treating these cancers. Herein we extracted and isolated from the medicinal plant Sophora alopecuroides L. a new natural product, dubbed Cytisine N-methylene-(4′,7-dihydroxy-3′-methoxy)-isoflavone (CNI1) that features a unique molecular framework. Our biochemical kinase assay suggested that one of its derivative CNI3 exhibited the best, micromolar (μM) inhibition activities against the EGFR (IC50 of 1.1 μM; Ki of 0.6 μM) and HER2 (IC50 of 3.5 μM; Ki of 1.8 μM) kinases. By contrast, another derivative CNI4 was most potent in inhibiting the EGFR-overexpressing A431 cancer cell line (IC50 of 45.5 μM) and the HER2-overexpressing BT-474 cancer cell line (IC50 of 32.9 μM), while the respective cellular activities of Lapatinib (a marketed drug) were 24.9 and 20.3 μM under the same assay condition. Moreover, both CNI3 and CNI4 showed desirable anti-metastatic efficacy in another two breast cancer models (viz., MDA-MB-231 and 4T1). In addition, we explored the inhibitory mechanisms of the CNIs against EGFR and HER2 by molecular dynamics simulation and revealed a novel mode of action that engages the cytisine and chromone moieties in CNIs. By combining structure- and ligand-based analysis, we further rationally engineered a new CNI compound that exhibits considerably improved cytotoxicity against both types of A431 and BT-474 cancer cells. Our study demonstrates the CNI compounds as a new class of EGFR/HER2 dual inhibitors and paves a way for their further development.

An experimental and computational study of new spiro-barbituric acid pyrazoline scaffolds: restricted rotationvs.annular tautomerism

A regioselective [3+2] cycloaddition (32CA) reaction to synthesize unsymmetric spiro-barbituric pyrazolines containing a chromone or phenolic pyrazole moiety was achieved, providing good to excellent yields.

Advances in the site-selective C-5, C-3 and C-2 functionalization of chromones via sp2 C-H activation.

In this work, site-selective C–H activation at C-5, C-3 and C-2 positions of chromones for the introduction of structural diversity to the chromone scaffold was studied. The keto group of the chromone moiety acts as the directing group for the selective functionalization of chromones at the C-5 position. Furthermore, the C–H functionalization at the electron-rich C-3 position of the chromone can be achieved using electrophilic coupling partners. The C–H functionalization at the C-2 position can be possible using nucleophilic coupling partners. The direct functionalization methods provide a better pathway for the generation of C-5, C-3 and C-2-substituted chromones with good atom economy than that of classical pre-functionalized reaction protocols.

Schiff base as a fluorescent sensor derived from chromone moiety for the effective detection of Zn (II) ions

A new Schiff base 5-[(4-Oxo-4H-chromen-3-ylmethylene)-amino]-1H-pyrimidine-2, 4‑dione (CUR) was synthesized from chromone moiety and identified as a colorimetric as well as a fluorescent probe for Zn2+ ions detection. Characterization of CUR was done by utilizing 1H NMR, 13C NMR, FTIR, and HRMS analytical techniques. UV–Vis absorption and fluorescence studies revealed that this probe CUR offered great selectivity and sensitivity towards Zn2+ ions above other added metal ions, namely; Cd2+, Hg2+, Ag+, Zr2+, Cr3+, Cu2+, Mn2+, Fe3+, Ni2+, Co2+, Al3+, and Pb2+. A 2:1 binding stoichiometry among CUR and Zn2+ ions was obtained using Job's plot analysis and further confirmed by 1H NMR titrations, and HRMS parameters. The binding constant (Ka) and limit of detection (LOD) for Zn2+ ions were measured to be 7.7 × 106M−1 and 9.6 × 10−9 M, respectively, using fluorimetric titrations with the help of the Benesi-Hildebrand equation (B-H equation). DFT computational studies also validated the results obtained from absorption and emission studies. The pH and time response studies ensured the stability of CUR and additionally, it was effectively implemented to quantify Zn2+ ions in the collected real water samples.

Dual inhibitors of Interleukin-6 and acetylcholinesterase for treatment of Alzheimer's disease: Design, docking, synthesis and biological evaluation

Multitarget compounds intercept two or more functionally complementary pathways simultaneously, and are therefore considered to have potential in effectively treating complex multifactorial diseases like Alzheimer's disease (AD). In the present study, novel molecules are designed by coupling a chromone and a N,N-disubstituted carbamoyl amine as pharmacophore for interleukin-6 (IL-6) and acetylcholinesterase (AChE) inhibition, respectively. Four series (Y1–Y4) of 40 compounds are designed by using alkyl linkers of different lengths (1–4 carbon atoms) for the coupling of the two selected pharmacophore. Docking of all designed compounds in AChE leads to the identification of twelve best fit compounds (Docking score >8.3). The data suggests that a 1- or 2-carbon atom linker is the most conducive to orient the pharmacophore for optimum binding with AChE active site. The predicted ADME properties of the 12 selected compounds suggest that these can cross the blood brain barrier (BBB) with good oral bioavailability. These compounds are synthesised and evaluated for anti-AChE activity. Five compounds, showing >45% inhibition of AChE, are further evaluated for IL-6 inhibitory activity. Compound Y1f is found to be the most potent inhibitor of both AChE and IL-6 (IC50 0.7 and 0.8 ​μM, respectively). It suggests that a chromone moiety connected to a piperidine ring through a 1-carbon atom linker may provide a useful template to medical chemists for the development of new chemical entities effective against AD.

Domino Reactions of Chromones with Heterocyclic Enamines

AbstractDomino reactions of heterocyclic enamines with chromone derivatives provides a convenient synthesis of a great variety of annulated heterocyclic ring systems. The course of the reaction depends on the type of substituent located at position 3 of the chromone. Reactions of 3-unsubstituted chromones, 3-nitrochromones, and 3-halochromones proceed by conjugate addition of the carbon atom of the enamine to carbon C-2 of the chromone, ring cleavage, and recyclization via the chromone carbonyl group. In the case of 3-formylchromes, 3-dichloroacetylchromone, 3-perfluoroalkanoylthiochromones, 3-(2-fluorobenzoyl)chromones, and 3-methoxalylchromones the final cyclization proceeds via the carbonyl group located outside the chromone moiety. The functional groups located at the carbonyl group at position 3 of the chromone allow for further synthetic transformations including additional ring closures.Contents1 Introduction2 3-Unsubstituted Chromones3 3-Nitrochromones4 3-Formylchromes5 3-Dichloroacetylchromone6 3-Perfluoroalkanoylthiochromones7 3-Methoxalylchromones8 3-(2-Fluorobenzoyl)chromones9 3-Halochromones10 Chromone-3-carboxylic Acids11 Conclusions

Chromone Derivatives with α-Glucosidase Inhibitory Activity from the Marine Fungus Penicillium thomii Maire.

The fungal strain YPGA3 was isolated from the sediments of the Yap Trench and identified as Penicillium thomii. Eight new chromone derivatives, named penithochromones M−T (1–8), along with two known analogues, 9 and 10, were isolated from the strain. The structures were established by detailed analyses of the spectroscopic data. The absolute configuration of the only chiral center in compound 1 was tentatively determined by comparing the experimental and the calculated specific rotations. Compounds 7 and 8 represent the first examples of chromone derivatives featuring a 5,7-dioxygenated chromone moiety with a 9-carbon side chain. Bioassay study revealed that compounds 6–10 exhibited remarkable inhibition against α-glucosidase with IC50 values ranging from 268 to 1017 μM, which are more active than the positive control acarbose (1.3 mmol).