- Thallium(III) p-tosylate-mediated oxidative [1,2] rearrangement of 2-naphthyl and 2-heteroarylchromanones
-
A practical and effective approach towards the synthesis of 3-heteroaryl-4H-chromen-4-ones by the oxidative [1,2] rearrangement of the respective 2-heteroaryl chroman-4-ones using thallium(III) p-tosylate is presented. The oxidative rearrangement of α- an
- Kurapati, Chidvilas,Muthukrishnan, Murugan,Singh, Om V.,Gundla, Rambabu
-
supporting information
p. 172 - 177
(2021/10/29)
-
- A novel one-pot synthesis of flavones
-
In this paper, a one-pot facile route for the BiCl3/RuCl3-mediated synthesis of functionalized flavones is described, including: (i) intermolecularortho-acylation of substituted phenols with cinnamoyl chlorides, and (ii) intramolecular cyclodehydrogenation of the resultingo-hydroxychalcones. The reaction conditions are discussed herein.
- Chang, Meng-Yang,Tsai, Min-Chen,Lin, Chun-Yi
-
p. 11655 - 11662
(2021/03/31)
-
- Exploring 3-hydroxyflavone scaffolds as mushroom tyrosinase inhibitors: synthesis, X-ray crystallography, antimicrobial, fluorescence behaviour, structure-activity relationship and molecular modelling studies
-
To explore new scaffolds as tyrosinase enzyme inhibitors remain an interesting goal in the drug discovery and development. In due course and our approach to synthesize bioactive compounds, a series of varyingly substituted 3-hydroxyflavone derivatives (1-23) were synthesized in one-pot reaction and screened for in?vitro against mushroom tyrosinase enzyme. The structures of newly synthesized compounds were unambiguously corroborated by usual spectroscopic techniques (FTIR, UV-Vis, 1H-, 13C-NMR) and mass spectrometry (EI-MS). The structure of compound 15 was also characterized by X-ray diffraction analysis. Furthermore, the synthesized compounds (1-23) were evaluated for their antimicrobial potential. Biological studies exhibit pretty good activity against most of the bacterial-fungal strains and their activity is comparable to those of commercially available antibiotics i.e. Cefixime and Clotrimazole. Amongst the series, the compounds 2, 4, 5, 6, 7, 10, 11, 14 and 22 exhibited excellent inhibitory activity against tyrosinase, even better than standard compound. Remarkably, the compound 2 (IC50 = 0.280 ± 0.010 μg/ml) was found almost sixfold and derivative 5 (IC50 = 0.230 ± 0.020 μg/ml) about sevenfold more active as compared to standard Kojic acid (IC50 =1.79 ± 0.6 μg/ml). Moreover, these synthetic compounds (1-23) displayed good to moderate activities against tested bacterial and fungal strains. Their emission behavior was also investigated in order to know their potential as fluorescent probes. The molecular modelling simulations were also performed to explore their binding interactions with active sites of the tyrosinase enzyme. Limited structure-activity relationship was established to design and develop new tyrosinase inhibitors by employing 2-arylchromone as a structural core in the future. Communicated by Ramaswamy H. Sarma.
- Ashraf, Jamshaid,Mughal, Ehsan Ullah,Sadiq, Amina,Bibi, Maryam,Naeem, Nafeesa,Ali, Anser,Massadaq, Anam,Fatima, Nighat,Javid, Asif,Zafar, Muhammad Naveed,Khan, Bilal Ahmad,Nazar, Muhammad Faizan,Mumtaz, Amara,Tahir, Muhammad Nawaz,Mirzaei, Masoud
-
p. 7107 - 7122
(2020/08/21)
-
- Design, synthesis, in silico studies, and evaluation of novel chalcones and their pyrazoline derivatives for antibacterial and antitubercular activities
-
A new series of naphthyl chalcones (3a–3p) and their pyrazoline derivatives (4a–4h) were synthesized using substituted acetophenones, substituted naphthaldehydes, and hydrazine hydrate as starting materials. All the synthesized compounds were characterize
- Pola, Shivani,Banoth, Karan Kumar,Sankaranarayanan, Murugesan,Ummani, Ramesh,Garlapati, Achaiah
-
p. 1819 - 1835
(2020/07/24)
-
- Chiral Hydroxytetraphenylene-Boron Complex Catalyzed Asymmetric Diels-Alder Cycloaddition of 2′-Hydroxychalcones
-
(S)-2,15-Cl2-DHTP-boron complex catalyst for the asymmetric Diels-Alder cycloaddition of 2′-hydroxychalcones and dienes was developed and tested. The resulting cyclohexenes with three chiral centers were obtained in high yields (up to 98%) with excellent stereoselectivities (up to >20:1 endo/exo, >99% ee). This catalytic system features high efficiency, broad substrate scopes, and mild reaction conditions. In addition, a DFT study was performed to explain the stereochemical course of the asymmetric induction.
- Chai, Guo-Li,Qiao, Yan,Zhang, Ping,Guo, Rong,Wang, Juan,Chang, Junbiao
-
supporting information
p. 8023 - 8027
(2020/11/02)
-
- Synthesis and hplc-ecd study of cytostatic condensed o,n-heterocycles obtained from 3-aminoflavanones
-
Racemic chiral O,N-heterocycles containing 2-arylchroman or 2-aryl-2H-chromene subunit condensed with morpholine, thiazole, or pyrrole moieties at the C-3-C-4 bond were synthesized with various substitution patterns of the aryl group by the cyclization of cis- or trans-3- aminoflavanone analogues. The 3-aminoflavanone precursors were obtained in a Neber rearrangement of oxime tosylates of flavanones, which provided the trans diastereomer as the major product and enabled the isolation of both the cis- and trans-diastereomers. The cis- and transaminoflavanones were utilized to prepare three diastereomers of 5-aryl-chromeno[4,3- b][1,4]oxazines. Antiproliferative activity of the condensed heterocycles and precursors was evaluated against A2780 and WM35 cancer cell lines. For a 3-(N-chloroacetylamino)-flavan-4-ol derivative, showing structural analogy with acyclic acid ceramidase inhibitors, 0.15 μM, 3.50 μM, and 6.06 μM IC50 values were measured against A2780, WM35, and HaCat cell lines, and apoptotic mechanism was confirmed. Low micromolar IC50 values down to 2.14 μM were identified for the thiazole- and pyrrole-condensed 2H-chromene derivatives. Enantiomers of the condensed heterocycles were separated by HPLC using chiral stationary phase, HPLC-ECD spectra were recorded and TDDFT-ECD calculations were performed to determine the absolute configuration and solution conformation. Characteristic ECD transitions of the separated enantiomers were correlated with the absolute configuration and effect of substitution pattern on the HPLC elution order was determined.
- Szappanos,Mándi, Attila,Gulácsi, Katalin,Lisztes, Erika,István Tóth, Balázs,Bíró, Tamás,Kónya-ábrahám, Anita,Kiss-Szikszai, Attila,Bényei, Attila,Antus, Sándor,Kurtán, Tibor
-
-
- Synthesis of 3-HCF2S-Chromones through Tandem Oxa-Michael Addition and Oxidative Difluoromethylthiolation
-
A simple protocol for the synthesis of difluoromethylthiolated chromen-4-ones using elemental sulfur and ClCF2CO2Na as the difluoromethylthiolating agent is described. Three-component reactions of 2′-hydroxychalcones, ClCF2CO2Na, and sulfur under basic conditions using TEMPO as the oxidant afforded HCF2S-containing 4H-chromen-4-one and 9H-thieno[3,2-b]chromen-9-one derivatives in good yield. The protocol is practical and efficient, and the starting materials are cheap and readily available.
- Zhang, Pingshun,Chen, Wanzhi,Liu, Miaochang,Wu, Huayue
-
supporting information
p. 9326 - 9329
(2019/12/24)
-
- Synthesis, structure-activity relationship and molecular docking studies of 3-O-flavonol glycosides as cholinesterase inhibitors
-
The prime objective of this research work is to prepare readily soluble synthetic analogues of naturally occurring 3-O-flavonol glycosides and then investigate the influence of various substituents on biological properties of synthetic compounds. In this context, a series of varyingly substituted 3-O-flavonol glycosides have been designed, synthesized and characterized efficiently. The structures of synthetic molecules were unambiguously corroborated by IR, 1H, 13C NMR and ESI-MS spectroscopic techniques. The structure of compound 22 was also analyzed by X-ray diffraction analysis. All the synthetic compounds (21–30) were evaluated for in vitro inhibitory potential against cholinesterase enzymes. The results displayed that most of the derivatives were potent inhibitors of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) with varying degree of IC50 values. The experimental results were further encouraged by molecular docking studies in order to explore their binding behavior with the active pocket of AChE and BChE enzymes. The experimental and theoretical results are in parallel with one another.
- Mughal, Ehsan Ullah,Javid, Asif,Sadiq, Amina,Murtaza, Shahzad,Zafar, Muhammad Naveed,Khan, Bilal Ahmad,Sumra, Sajjad Hussain,Tahir, Muhammad Nawaz,Kanwal,Khan, Khalid Mohammed
-
p. 3696 - 3706
(2018/06/19)
-
- Flavone derivatives, preparation method thereof and anticancer agent
-
The present invention relates to a flavone derivative, a manufacturing method thereof and an anticancer agent including the same. Compounds represented by chemical formula 1 and chemical formula 2 according to the present invention are excellent in antica
- -
-
Paragraph 0175-0179
(2018/05/15)
-
- Design, synthesis and MAO inhibitory activity of 2-(arylmethylidene)-2,3-dihydro-1-benzofuran-3-one derivatives
-
A series of 2-(arylmethylidene)-2,3-dihydro-1-benzofuran-3-one derivatives (aurones, 1–20) were synthesized and screened for their inhibitory activity against hMAO. Seventeen compounds (1–5, 7–17, 19) were found to be selective towards hMAO-B, while two w
- Badavath, Vishnu Nayak,Nath, Chandrani,Ganta, Narayana Murthy,Ucar, Gulberk,Sinha, Barij Nayan,Jayaprakash, Venkatesan
-
p. 1528 - 1532
(2017/07/17)
-
- Luminescence, circular dichroism and in silico studies of binding interaction of synthesized naphthylchalcone derivatives with bovine serum albumin
-
Chalcones possess various biological properties, for example, antimicrobial, anti-inflammatory, analgesic, antimalarial, anticancer, antiprotozoal and antitubercular activity. In this study, naphthylchalcone derivatives were synthesized and characterized
- Pasricha, Sharda,Sharma, Deepti,Ojha, Himanshu,Gahlot, Pragya,Pathak, Mallika,Basu, Mitra,Chawla, Raman,Singhal, Sugandha,Singh, Anju,Goel, Rajeev,Kukreti, Shrikant,Shukla, Shefali
-
p. 1252 - 1262
(2017/10/05)
-
- Synthesis and antiviral activity of 2-aryl-4H-chromen-4-one derivatives against Chikungunya virus
-
A series of nineteen 2-aryl-4H-chromen-4-one derivatives 2a-2s were synthesized and evaluated for their antiviral activity against Chikungunya virus (LR2006-OPY1) in Vero cell culture by CPE reduction assay. Three compounds 2a, 2b and 2g, were found to be active at concentration of (IC50) 0.44 μM, 0.45 μM and 2.02 μM, respectively. Compounds having heterocyclic ring 2a and 2b at the 2nd position of the chromenone were found to be potent inhibitor of ChikV. Cytotoxicity studies were performed using Vero cell culture, compounds 2a and 2b exhibited SI of ≥100. Molecular docking simulation has been carried out to understand the possible mechanism of action.
- Badavath, Vishnu N.,Jadav, Surender S.,Pastorino, Boris,De Lamballerie, Xavier,Sinha, Barij N.,Jayaprakash, Venkatesan
-
p. 1019 - 1024
(2016/11/25)
-
- Monoamine oxidase inhibitory activity of 2-aryl-4H-chromen-4-ones
-
A series of twenty 2-aryl-4H-chromen-4-one (flavones) derivatives (3a-3s) were synthesized and tested for hMAO inhibitory activity. Fifteen compounds (3a, 3c, 3e-3h, 3j-3p, 3r, 3s) were found to be selective towards MAO-B, while 3d was selective towards MAO-A, and 3b, 3i and 3q were non-selective. Experimental Selectivity Index for MAO-B ranges from 2.0 (3g, 3p) to 30.0 (3j). Compound 3j, which is carrying 3,4-di-OMeC6H3 groups at R position on the molecule, was found to be potent MAO-B inhibitor amongst the fifteen with Ki value for MAO-B of 0.16 ± 0.01 lM comparable to that of standard drug, Selegiline (Ki for MAO-B is 0.16 ± 0.01 μM). Compound 3j also appeared as the most selective MAO-B inhibitor according to its best selectivity index (30.0), which is comparable to that of Selegiline (SIMAO-B = 35.0). Molecular docking and molecular dynamics simulation studies were carried out using Autodock-4.0 and Amber12 to understand the molecular level interaction and energy relation of MAO isoforms with selective inhibitors (3d and 3j). Simulation results are in good agreement with the experimental results. Leads identified may further be explored to develop potent isoform specific inhibitors of MAO.
- Nayak, Badavath Vishnu,Ciftci-Yabanoglu,Bhakat, Soumendranath,Timiri, Ajay Kumar,Sinha, Barij N.,Ucar,Soliman, Mahmoud E. S.,Jayaprakash, Venkatesan
-
-
- Enantioselective biomimetic cyclization of 2′-hydroxychalcones to flavanones
-
A new family of organocatalysts based on aminoquinoline and pyrrolidine have been developed and shown to catalyze the direct and highly enantioselective cyclization of 2′-hydroxychalcones in imitation of the natural process of chalcone cyclization. The straightforward synthetic process occurs under mild reaction conditions, tolerates moisture and air, and gives an enantiomeric excess up to 99%. This approach provides a facile and efficient access to chiral flavanones.
- Zhang, Yan-Lei,Wang, Yong-Qiang
-
supporting information
p. 3255 - 3258
(2014/06/09)
-
- Synthesis and effects on cell viability of flavonols and 3-methyl ether derivatives on human leukemia cells
-
Flavonoids are polyphenolic compounds which display an array of biological activities and are considered potential antitumor agents. Here we evaluated the antiproliferative activity of selected synthetic flavonoids against human leukemia cell lines. We found that 4′-bromoflavonol (flavonol 3) was the most potent. This compound inhibited proliferation in a concentration-dependent manner, induced apoptosis and blocked cell cycle progression at the S phase. Cell death was found to be associated with the cleavage and activation of multiple caspases, the activation of the mitogen-activated protein kinase pathway and the up-regulation of two death receptors (death receptor 4 and death receptor 5) for tumor necrosis factor-related apoptosis-inducing ligand. Moreover, combined treatments using 4′-bromoflavonol and TRAIL led to an increased cytotoxicity compared to single treatments. These results provide a basis for further exploring the potential applications of this combination for the treatment of cancer.
- Burmistrova, Olga,Marrero, María Teresa,Estévez, Sara,Welsch, Isabel,Brouard, Ignacio,Quintana, José,Estévez, Francisco
-
-
- Monoamine oxidase inhibitory activity of 2-aryl-4H-chromen-4-ones
-
A series of twenty 2-aryl-4H-chromen-4-one (flavones) derivatives (3a-3s) were synthesized and tested for hMAO inhibitory activity. Fifteen compounds (3a, 3c, 3e-3h, 3j-3p, 3r, 3s) were found to be selective towards MAO-B, while 3d was selective towards MAO-A, and 3b, 3i and 3q were non-selective. Experimental Selectivity Index for MAO-B ranges from 2.0 (3g, 3p) to 30.0 (3j). Compound 3j, which is carrying 3,4-di-OMeC6H3 groups at R position on the molecule, was found to be potent MAO-B inhibitor amongst the fifteen with Ki value for MAO-B of 0.16 ± 0.01 μM comparable to that of standard drug, Selegiline (Ki for MAO-B is 0.16 ± 0.01 μM). Compound 3j also appeared as the most selective MAO-B inhibitor according to its best selectivity index (30.0), which is comparable to that of Selegiline (SIMAO-B = 35.0). Molecular docking and molecular dynamics simulation studies were carried out using Autodock-4.0 and Amber12 to understand the molecular level interaction and energy relation of MAO isoforms with selective inhibitors (3d and 3j). Simulation results are in good agreement with the experimental results. Leads identified may further be explored to develop potent isoform specific inhibitors of MAO.
- Badavath, Vishnu Nayak,Ciftci-Yabanoglu,Bhakat, Soumendranath,Timiri, Ajay Kumar,Sinha, Barij N.,Ucar,Soliman, Mahmoud E.S.,Jayaprakash, Venkatesan
-
-
- Ruthenium-NHC-catalyzed asymmetric hydrogenation of flavones and chromones: General access to enantiomerically enriched flavanones, flavanols, chromanones, and chromanols
-
Two to four! Readily available flavones and chromones were efficiently converted into four valuable chiral classes of O-heterocycles - flavanones, chromanones, flavanols, and chromanols - by means of an enantioselective Ru/NHC-catalyzed hydrogenation process (see scheme; NHC=N-heterocyclic carbene, PCC=pyridinium chlorochromate). Copyright
- Zhao, Dongbing,Beiring, Bernhard,Glorius, Frank
-
supporting information
p. 8454 - 8458
(2013/09/02)
-
- Asymmetric ion-pairing catalysis of the reversible cyclization of 2'-hydroxychalcone to flavanone: Asymmetric catalysis of an equilibrating reaction
-
The asymmetric catalytic cyclization of the simple 2'-hydroxychalcone (1) to flavanone (2), a model for the chalcone isomerase reaction, has been realized as a catalytic asymmetric ion-pairing process with chiral quaternary ammonium salts (e.g., 9-anthracenylmethlycinchoninium chloride; 9-Am-CN-Cl) and NaH as small-molecule co-catalyst. In toluene/CHCl3 solution, the process reaches an intrinsic enantioselectivity of up to S = 14.4 (er = 93.5:6.5). The reversible reaction proceeds in two steps: A fast initial reaction approaches a quasi-equilibrium with KR/S = 4.5, followed by a second, slow racemization phase approaching Krac = 9. A simple mechanistic model featuring a living ion-pairing catalysis with full reversibility is proposed. Deuterium transfer from co-solvent CDCl3 to product 2 and isolation of a Michael conjugate formed from 2 and 1 demonstrate the intermediacy of flavanone enolate ion pairs. A kinetic model shows good agreement with the experimentally observed, peculiar, time-dependent evolution of the species concentrations and the enantiomeric excess of 2. The reaction is a chemical model of the chalcone isomerase enzymatic reaction. Furthermore, it is an ideal model for studying the characteristic behavior of reversible asymmetric catalyses close to their equilibria.
- Hintermann, Lukas,Dittmer, Claudia
-
supporting information
p. 5573 - 5584
(2012/11/13)
-
- Synthesis and characterization of Ru(II)-DMSO-Cl-chalcone complexes: DNA binding, nuclease, and topoisomerase II inhibitory activity
-
The complexes of type cis-[Ru(S-DMSO)3(R-CO-CH-CH-R′)Cl] (R = 2-hydroxyphenyl for all, R′ = phenyl 1, naphthyl 2, anthracenyl 3, thiophene 4, 3-methyl thiophene 5) are synthesized and characterized using spectroscopic (IR, 1H and su
- Gaur, Ruchi,Mishra, Lallan
-
scheme or table
p. 3059 - 3070
(2012/04/23)
-
- An unexpected rearrangement-hydration reaction sequence of 2H-chromenes to dihydrochalcones under catalysis of HAuCl4
-
2-Aryl-2H-chromenes in aqueous DCM medium under catalysis of HAuCl 4 are converted into 3-(2-hydroxyaryl)-1-arylpropan-1-ones through hydration-rearrangement reaction sequence in very good yield. The key step probably involves the [1,5] hydride shift followed by the hydrolysis under the reaction condition. The notable advantages of this method are operational simplicity and ease of isolation of products and also provide a pathway to convert the chalcone into DHCs with the transposition of carbonyl group. 2012 Elsevier Ltd. All rights reserved.
- Maiti, Gourhari,Kayal, Utpal,Karmakar, Rajiv,Bhattacharya, Rudraksha N.
-
p. 6321 - 6325,5
(2012/12/12)
-
- Ionic liquid mediated Cu-catalyzed cascade oxa-Michael-oxidation: Efficient synthesis of flavones under mild reaction conditions
-
Flavonoids are a class of natural products, found in a wide range of vascular plants and dietary components. Their low toxicity and extensive biological activities, including anti-cancer and anti-bacterial, have made them attractive candidates to serve as therapeutic agents for many diseases. Herein, we disclose a highly efficient synthetic method of CuI-catalyzed cascade oxa-Michael-oxidation, using chalcones as substrates, mediated by the ionic liquid [bmim][NTf2] at a low temperature. This efficient synthetic method has demonstrated high synthetic utility and can afford flavones in good to high yields (up to 98%).
- Du, Zhiyun,Ng, Huifen,Zhang, Kun,Zeng, Huaqiang,Wang, Jian
-
supporting information; experimental part
p. 6930 - 6933
(2011/11/04)
-