- Design, and facile synthesis of 1,3 diaryl-3-(arylamino)propan-1-one derivatives as the potential alpha-amylase inhibitors and antioxidants
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Diabetes is the most prevalent metabolic disorder causing a high rate of mortality and morbidity. Recently alpha-amylase is reported to be good drug design target for the treatment of diabetes mellitus. We have designed 116 molecules based on aza-Michael
- Bashary, Roqia,Khatik, Gopal L.
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Read Online
- Deamination of cis and trans-aziridines using diethyl thiourea and iodine
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Various non-activated aziridines reacted with diethyl thiourea in the presence of iodine in DCM to give the corresponding trans-alkenes as a sole product in good to excellent yields. Iranian Chemical Society 2012.
- Samimi, Heshmat A.,Shams, Zahra,Momeni, Ahmad R.
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Read Online
- Combined 3D-QSAR and docking analysis for the design and synthesis of chalcones as potent and selective monoamine oxidase B inhibitors
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Monoamine oxidases (MAOs) are important targets in medicinal chemistry, as their inhibition may change the levels of different neurotransmitters in the brain, and also the production of oxidative stress species. New chemical entities able to interact selectively with one of the MAO isoforms are being extensively studied, and chalcones proved to be promising molecules. In the current work, we focused our attention on the understanding of theoretical models that may predict the MAO-B activity and selectivity of new chalcones. 3D-QSAR models, in particular CoMFA and CoMSIA, and docking simulations analysis have been carried out, and their successful implementation was corroborated by studying twenty-three synthetized chalcones (151–173) based on the generated information. All the synthetized molecules proved to inhibit MAO-B, being ten out of them MAO-B potent and selective inhibitors, with IC50 against this isoform in the nanomolar range, being (E)-3-(4-hydroxyphenyl)-1-(2,2-dimethylchroman-6-yl)prop-2-en-1-one (152) the best MAO-B inhibitor (IC50 of 170 nM). Docking simulations on both MAO-A and MAO-B binding pockets, using compound 152, were carried out. Calculated affinity energy for the MAO-A was +2.3 Kcal/mol, and for the MAO-B was ?10.3 Kcal/mol, justifying the MAO-B high selectivity of these compounds. Both theoretical and experimental structure–activity relationship studies were performed, and substitution patterns were established to increase MAO-B selectivity and inhibitory efficacy. Therefore, we proved that both 3D-QSAR models and molecular docking approaches enhance the probability of finding new potent and selective MAO-B inhibitors, avoiding time-consuming and costly synthesis and biological evaluations.
- Mellado, Marco,González, César,Mella, Jaime,Aguilar, Luis F.,Vi?a, Dolores,Uriarte, Eugenio,Cuellar, Mauricio,Matos, Maria J.
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- Inhibition of Caco-2 and MCF-7 cancer cells using chalcones: synthesis, biological evaluation and computational study
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Cancer is the second death cause worldwide, with breast and colon cancer among the most prevalent types. Traditional treatment strategies have several side effects that inspire the development of novel anticancer agents derived from natural sources, like chalcone derivatives. For this investigation, twenty-three chalcones (4a-w) were synthesized and evaluated as antiproliferative agents against MCF-7 and Caco-2 cells, finding three and two compounds with similar or higher antiproliferative activity than daunorubicin, while only two chalcones showed better selectivity indexes than daunorubicin on MCF-7. From these results, we developed good-performance QSAR models (r > 0.850, q2>0.650), finding several structural features that could modify chalcone activity and selectivity. According to these models, chalcones 4w and 4t have high potency and selectivity against Caco-2 and MCF-7, respectively, which make them attractive candidates for hit-to-lead development of ROS-independent pro apoptotic agents.
- Aguilar, Luis F.,Coddou, Claudio,Jara-Gutierrez, Carlos,Mellado, Marco,Reyna-Jeldes, Mauricio,Villena, Joan,Weinstein-Oppenheimer, Caroline
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supporting information
(2021/10/02)
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- Synthesis, characterization and antichagasic evaluation of thiosemicarbazones prepared from chalcones and dibenzalacetones
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Chagas disease is a neglected disease, being one of the leading causes of death from infectious diseases. In view of the severity of this pathology, this work describes the synthesis of new thiosemicarbazones derived from chalcones and dibenzalacetones as potential drugs for the treatment of this disease. The structures of all compounds were elucidated by infrared (IR) and nuclear magnetic resonance (1H and 13C NMR) spectroscopies. The chalcone derived thiosemicarbazones 10-14 were tested against the intracellular amastigote form of the protozoan Trypanosoma cruzi and had their cytotoxicity assessed using LLC-MK2 cells. The compound 10 (IC50 = 12.25 μM) presented the best activity when compared with the standard drug benznidazole (IC50 = 5.64 μM).
- da Silva, Aline Alves,Maia, Pedro Ivo da Silva,Lopes, Carla Duque,de Albuquerque, Sergio,Valle, Marcelo Siqueira
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- Synthesis and evaluation of chalcone derivatives as novel sunscreen agent
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Ultraviolet (UV) irradiation is a serious problem for skin health thus the interest in the research to develop sunscreen agent has been increasing. Chalcone is a promising compound to be developed as its chromophore absorbs in the UV region. Therefore, in
- Jumina, Jumina,Lee, Wonkoo,Swasono, Respati Tri,Wijayanti, Lucia Wiwid
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- Borane-Catalyzed, Chemoselective Reduction and Hydrofunctionalization of Enones Enabled by B-O Transborylation
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The use of stoichiometric organoborane reductants in organic synthesis is well established. Here these reagents have been rendered catalytic through an isodesmic B-O/B-H transborylation applied in the borane-catalyzed, chemoselective alkene reduction and formal hydrofunctionalization of enones. The reaction was found to proceed by a 1,4-hydroboration of the enone and B-O/B-H transborylation with HBpin, enabling catalyst turnover. Single-turnover and isotopic labeling experiments supported the proposed mechanism of catalysis with 1,4-hydroboration and B-O/B-H transborylation as key steps.
- Nicholson, Kieran,Langer, Thomas,Thomas, Stephen P.
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supporting information
p. 2498 - 2504
(2021/04/13)
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- A new method for the synthesis of chalcone derivatives promoted by PPh3/I2under non-alkaline conditions
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A straightforward and general method has been developed for the synthesis of chalcone derivatives by a Claisen-Schmidt reaction in the presence of PPh3/I2 in 1,4-dioxane under reflux temperatures. With the condensation of the aromatic ketone and aldehyde occurring at non-strongly alkaline conditions, our proposed method significantly expands the range of applicable substrates, especially for groups that are unstable under alkaline conditions.
- Xue, Kangsheng,Sun, Guoxiang,Zhang, Yanzhi,Chen, Xubing,Zhou, Yang,Hou, Jinjun,Long, Huali,Zhang, Zijia,Lei, Min,Wu, Wanying
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supporting information
p. 625 - 634
(2020/11/23)
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- From Celecoxib to a Novel Class of Phosphodiesterase 5 Inhibitors: Trisubstituted Pyrazolines as Novel Phosphodiesterase 5 Inhibitors with Extremely High Potency and Phosphodiesterase Isozyme Selectivity
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A ligand-based approach involving systematic modifications of a trisubstituted pyrazoline scaffold derived from the COX2 inhibitor, celecoxib, was used to develop novel PDE5 inhibitors. Novel pyrazolines were identified with potent PDE5 inhibitory activit
- Abdel-Halim, Mohammad,Sigler, Sara,Racheed, Nora A. S.,Hefnawy, Amr,Fathalla, Reem K.,Hammam, Mennatallah A.,Maher, Ahmed,Maxuitenko, Yulia,Keeton, Adam B.,Hartmann, Rolf W.,Engel, Matthias,Piazza, Gary A.,Abadi, Ashraf H.
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supporting information
p. 4462 - 4477
(2021/05/04)
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- Synthesis, characterization and biological evaluation of new 3,5-disubstituted-pyrazoline derivatives as potential anti-Mycobacterium tuberculosis H37Ra compounds
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A total of fourteen pyrazoline derivatives were synthesized through cyclo-condensation reactions by chalcone derivatives with different types of semicarbazide. These compounds were characterized by IR, 1D-NMR (1H, 13C and Distortionless Enhancement by Polarization Transfer-DEPT-135) and 2D-NMR (COSY, HSQC and HMBC) as well as mass spectroscopy analysis (HRMS). The synthesized compounds were tested for their antituberculosis activity against Mycobacterium tuberculosis H37Ra in vitro. Based on this activity, compound 4a showed the most potent inhibitory activity, with a minimum inhibitory concentration (MIC) value of 17 μM. In addition, six other synthesized compounds, 5a and 5c–5g, exhibited moderate activity, with MIC ranges between 60 μM to 140 μM. Compound 4a showed good bactericidal activity with a minimum bactericidal concentration (MBC) value of 34 μM against Mycobacterium tuberculosis H37Ra. Molecular docking studies for compound 4a on alpha-sterol demethylase was done to understand and explore ligand– receptor interactions, and to hypothesize potential refinements for the compound.
- Azmi, Mohamad Nurul,Che Omar, Mohammad Tasyriq,Osman, Hasnah,Parumasivam, Thaigarajan,Supratman, Unang,Wong, Kok Tong
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- Mechanochemical Syntheses of N-Containing Heterocycles with TosMIC
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A mechanochemical van Leusen pyrrole synthesis with a base leads to 3,4-disubstitued pyrroles in moderate to excellent yields. The developed protocol is compatible with a range of electron-withdrawing groups and can also be applied to the synthesis of oxazoles. Attempts to mechanochemically convert the resulting pyrroles into porphyrins proved to be difficult.
- Bolm, Carsten,Molitor, Claude,Rissanen, Kari,Schumacher, Christian,Smid, Sabrina,Truong, Khai-Nghi
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p. 14213 - 14222
(2021/09/07)
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- Designed pincer ligand supported Co(ii)-based catalysts for dehydrogenative activation of alcohols: Studies onN-alkylation of amines, α-alkylation of ketones and synthesis of quinolines
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Base-metal catalystsCo1,Co2andCo3were synthesized from designed pincer ligandsL1,L2andL3having NNN donor atoms respectively.Co1,Co2andCo3were characterized by IR, UV-Vis. and ESI-MS spectroscopic studies. Single crystal X-ray diffraction studies were investigated to authenticate the molecular structures ofCo1andCo3. CatalystsCo1,Co2andCo3were utilized to study the dehydrogenative activation of alcohols forN-alkylation of amines, α-alkylation of ketones and synthesis of quinolines. Under optimized reaction conditions, a broad range of substrates including alcohols, anilines and ketones were exploited. A series of control experiments forN-alkylation of amines, α-alkylation of ketones and synthesis of quinolines were examined to understand the reaction pathway. ESI-MS spectral studies were investigated to characterize cobalt-alkoxide and cobalt-hydride intermediates. Reduction of styrene by evolved hydrogen gas during the reaction was investigated to authenticate the dehydrogenative nature of the catalysts. Probable reaction pathways were proposed forN-alkylation of amines, α-alkylation of ketones and synthesis of quinolines on the basis of control experiments and detection of reaction intermediates.
- Singh, Anshu,Maji, Ankur,Joshi, Mayank,Choudhury, Angshuman R.,Ghosh, Kaushik
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p. 8567 - 8587
(2021/06/30)
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- Enantioselective Stetter Reactions Catalyzed by Bis(amino)cyclopropenylidenes: Important Role for Water as an Additive
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The first highly enantioselective intermolecular Stetter reaction using simple enones is reported. A series of novel chiral BAC structures were designed and prepared. They were tested in the Stetter reaction with simple aldehydes and enones. The products were generated in excellent yields and enantioselectivities (up to 94% ee). Surprisingly, a substoichiometric amount of water was crucial to obtain high enantioselectivities. Chiral BACs were also shown to catalyze 1,6-conjugate addition reactions with paraquinone methides enantioselectively.
- Rezazadeh Khalkhali, Mehran,Wilde, Myron M. D.,Gravel, Michel
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supporting information
p. 155 - 159
(2021/01/09)
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- Reaction rate differences between organotrifluoroborates and boronic acids in BINOL-catalyzed conjugate addition to enones
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Enantioselective organocatalysis has been successfully employed in combination with trifluoroborate reagents for novel organic transformations over the last decade. However, no experimental rate studies of these reactions have been reported. Herein we report Hammett plot analysis of the organocatalyzed enantioselective conjugate addition of alkenyl, aryl, and heteroaryl trifluoroborate salts to chalcone derivatives with substitution at both the β-aryl and keto-aryl positions. The rate trend for keto-aryl substitution diverges from that of boronic acid nucleophiles in that the keto-aryl substituent for trifluoroborate salts does not measurably impact reaction rate in a manner consistent with charge stabilization. In addition, variable temperature NMR in combination with quantitative thin-layer chromatography (TLC) analysis suggests that the reaction is impacted by the low solubility of the trifluoroborate salts, so particle size and stirring speed affect reaction rates.
- Brooks, Bailey,Hiller, Noemi,May, Jeremy A.
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supporting information
(2021/09/28)
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- C3 amino-substituted chalcone derivative with selective adenosine rA1 receptor affinity in the micromolar range
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Abstract: To identify novel adenosine receptor (AR) ligands based on the chalcone scaffold, herein the synthesis, characterization and in vitro and in silico evaluation of 33 chalcones (15–36 and 37–41) and structurally related compounds (42–47) are reported. These compounds were characterized by radioligand binding and GTP shift assays to determine the degree and type of binding affinity, respectively, against rat (r) A1 and A2A ARs. The chalcone derivatives 24, 29, 37 and 38 possessed selective A1 affinity below 10?μM, and thus, are the most active compounds of the present series; compound 38 was the most potent selective A1 AR antagonist (Ki (r) = 1.6?μM). The structure–affinity relationships (SAR) revealed that the NH2-group at position C3 of ring A of the chalcone scaffold played a key role in affinity, and also, the Br-atom at position C3′ on benzylidene ring B. Upon in vitro and in silico evaluation, the novel C3 amino-substituted chalcone derivative 38—that contains an α,?-unsaturated carbonyl system and easily allows structural modification—may possibly be a synthon in future drug discovery. Graphic abstract: C3 amino-substituted chalcone derivative (38) with C3′ Br substitution on benzylidene ring B possesses selective adenosine rA1 receptor affinity in micromolar range.[Figure not available: see fulltext.]
- Janse van Rensburg, Helena D.,Legoabe, Lesetja J.,Terre’Blanche, Gisella
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p. 1581 - 1605
(2020/11/20)
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- Ligand-Free Palladium-Catalyzed Carbonylative Suzuki Couplings of Vinyl Iodides with Arylboronic Acids under Substoichiometric Base Conditions
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A ligand-free palladium-catalyzed carbonylation of vinyl iodides with arylboronic acids, permitting the synthesis of chalcones and α-branched enones, has been established. This reaction proceeds smoothly at ambient pressure and temperature, and works well even with a substoichiometric amount of base. Importantly, this mild, efficient, and operationally simple protocol is suitable for the late-stage functionalization of an epiandrosterone-derived complex molecule.
- Yang, Zhiyuan,Gong, Pei-Xue,Chen, Junjie,Zhang, Jie,Gong, Xu,Han, Wei
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supporting information
p. 1207 - 1212
(2021/06/18)
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- Synthesis and characterization of 1,3,5-triarylpyrazol-4-ols and 3,5-diarylisoxazol-4-ols from chalcones and theoretical studies of the stability of pyrazol-4-ol toward acid dehydration
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The synthesis of diverse pyrazol-4-ol and isoxazole-4-ol heterocycles involving only 3 reaction steps is reported in this study. However, the synthesis of carboxamide pyrazol-4-ol has failed in the conditions used in the synthesis, acid methanol solution. The carboxamide pyrazol-4-ol decomposes via dehydration, forming the respective pyrazol. Theoretical calculations were used to elucidate the dehydration reaction. We have found a mechanism for acid-catalyzed dehydration that can explain the experimental observations. The calculated free energy profile for acid-catalyzed dehydration of the carboxamide pyrazol-4-ol and phenylpyrazole-4-ol point out that the latter is more stable in relation dehydration, with a dehydration rate 100 times smaller in acid methanol solution.
- Cipagauta Esquivel, Edna Carolina,Rufino, Virgínia Camila,Trindade Nogueira, Matheus Henrique,Carbonaro Souza, Ana Carolina,Pliego Júnior, Josefredo Rodriguez,Valle, Marcelo Siqueira
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- Biocatalytic green alternative to existing hazardous reaction media: Synthesis of chalcone and flavone derivatives via the Claisen-Schmidt reaction at room temperature
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Owing to the increasing amount of waste materials around the globe, the conversion of waste or secondary by-products to value-added products for various applications has gained significant interest. Herein, two novel agro-food waste products, Musa sp. 'Malbhog' peel ash (MMPA) and Musa Champa Hort. ex Hook. F. peel ash (MCPA) are used as catalysts to promote an inexpensive, efficient and eco-friendly carbon-carbon bond forming crossed aldol reaction at room temperature in solvent free conditions. Furthermore, the resulting products were subjected to reactions with these promoters in an oxygen atmosphere and led to the formation of novel flavone derivatives. Moreover, the used catalysts were properly characterized using different sophisticated analytical techniques such as Fourier-transform infrared spectroscopy (FT-IR), X-ray diffractometry (XRD), Brunauer-Emmett-Teller analysis (BET), Raman spectroscopy, scanning electron microscopy energy dispersive X-ray spectroscopy (SEM-EDS), transition electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA) along with element detection using atomic absorption spectroscopy and ion chromatographic methods. These two approaches are metal free, as well as being devoid of any extra additives, co-catalysts, harsh conditions, the use of column chromatography for purification and result in a higher yield of the product within a short space of time. The catalytic abilities of the promoter were also examined to synthesize important bioactive molecules such as butein and apigenin at room temperature. With gram scale synthesis of the chalcone derivatives, the used catalysts (MMPA and MCPA) were further reused for five cycles and did not demonstrate any loss in catalytic activity.
- Tamuli, Kashyap J.,Sahoo, Ranjan K.,Bordoloi, Manobjyoti
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supporting information
p. 20956 - 20965
(2020/12/31)
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- Computational modeling and target synthesis of monomethoxy-substituted o-diphenylisoxazoles with unexpectedly high antimitotic microtubule destabilizing activity
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The ability of monomethoxy-substituted o-diphenylisoxazoles 2a-d to interact with the colchicine site of tubulin was predicted using computational modeling, docking studies, and calculation of binding affinity. The respective molecules were synthesized in high yields by three steps reaction using easily available benzaldehydes, acetophenones, and arylnitromethanes as starting material. The calculated antitubulin effect was confirmed in vivo in a sea urchin embryo model. Compounds 2a and 2c showed high antimitotic microtubule destabilizing activity compared to that of CA4. Isoxazole 2a also exhibited significant cytotoxicity against human cancer cells in NCI60 screen. For the first time, isoxazole-linked CA4 derivatives 2a and 2c with only one methoxy substituent were identified as potent antimitotic microtubule destabilizing agents. These molecules could be considered as promising structures for further optimization.
- Stroylov, Victor S.,Svitanko, Igor V.,Maksimenko, Anna S.,Kislyi, Victor P.,Semenova, Marina N.,Semenov, Victor V.
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supporting information
(2020/10/21)
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- Methoxychalcones: Effect of methoxyl group on the antifungal, antibac-terial and antiproliferative activities
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Background: Chalcones substituted by methoxyl groups have presented a broad spec-trum of bioactivities, including antifungal, antibacterial and antiproliferative effects. However, a clear and unambiguous investigation about the relevance of this substituent on the chalcone framework has not been described. Objective: The purpose of this work is to assess the antibacterial, antifungal and antiproliferative activities of the two series of seventeen synthesized regioisomeric methoxychalcones. Series I and II were constituted by chalcones substituted by methoxyl groups on rings A (5–12) and B (13–21), respectively. In addition, the library of methoxychalcones was submitted to in silico drug-likeness and pharmacokinetics properties predictions. Methods: Methoxychalcones were synthesized and their structures were confirmed by NMR spectral data analyses. Evaluations of antimicrobial activity were performed against five species of Candida, two Gram-negative and five Gram-positive species. For antiproliferative activity, methoxychalcones were evaluated against four human tumorigenic cell lines, as well as human non-tumorigenic keratinocytes. Drug-likeness and pharmacokinetics properties were predicted using Molinspiration and PreADMET toolkits. Results: In general, chalcones of series I are the most potent antifungal, antibacterial and antipro-liferative agents. 3’, 4’, 5’-Trimethoxychalcone (12) demonstrated potent antifungal activity against Candida krusei (MIC = 3.9 μg/mL), eight times more potent than fluconazole (reference antifungal drug). 3’-Methoxychalcone (6) displayed anti-Pseudomonas activity (MIC = 7.8 μg/mL). 2’,5’-Dimethoxychalcone (9) displayed potent antiproliferative effect against C-33A (cervix), A-431 (skin) and MCF-7 (breast), with IC50 values ranging from 7.7 to 9.2 μM. Its potency was superior to curcumin (reference antiproliferative compound), which exhibited IC50 values ranging from 10.4 to 19.0 μM. Conclusion: Our studies corroborated the relevance of methoxychalcones as antifungal, antibacte-rial and antiproliferative agents. In addition, we elucidated influence of the position and number of methoxyl groups toward bioactivity. In silico predictions indicated good drug-likeness and phar-macokinetics properties to the library of methoxychalcones.
- Marques, Beatriz C.,Santos, Mariana B.,Anselmo, Daiane B.,Monteiro, Diego A.,Gomes, Eleni,Saiki, Marilia F. C.,Rahal, Paula,Rosalen, Pedro L.,Sardi, Janaina C. O.,Regasini, Luis O.
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p. 881 - 891
(2020/08/19)
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- Efficient Organoruthenium Catalysts for α-Alkylation of Ketones and Amide with Alcohols: Synthesis of Quinolines via Hydrogen Borrowing Strategy and their Mechanistic Studies
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A new family of phosphine free organometallic ruthenium(II) catalysts (Ru1–Ru4) supported by bidentate NN Schiff base ligands (L1–L4 where L1=N,N-dimethyl-4-((2-phenyl-2-(pyridin-2-ylmethyl)hydrazineylidene)methyl) aniline, L2=N,N-diethyl-4-((2-phenyl-2-(pyridin-2-ylmethyl)hydrazineylidene)methyl)aniline, L3=N,N-dimethyl-4-((2-phenyl-2-(pyridin-2-yl)hydrazineylidene)methyl)- aniline and L4=N,N-diethyl-4-((2-phenyl-2-(pyridin-2-yl)hydrazineylidene)methyl) aniline) was prepared and characterized. These half-sandwich complexes acted as catalysts for C?C bond formation and exhibited excellent performance in the dehydrogenative coupling of ketones and amides. In the synthesis of C–C bonds, alcohols were utilized as the alkylating agent. A broad range of substrates, including sterically hindered ketones and alcohols, were well tolerated under the optimized conditions (TON up to 47000 and TOF up to 11750 h?1). This ruthenium (II) catalysts were also active towards the dehydrogenative cyclization of o-amino benzyl alcohol for the formation of quinolines derivatives. Various polysubstituted quinolines were synthesized in moderate to excellent yields (TON up to 71000 and TOF up to 11830 h?1). Control experiments were carried out and the ruthenium hydride intermediate was characterized to support the reaction mechanism and a probable reaction pathway of dehydrogenative coupling for the C?C bond formation has been proposed.
- Maji, Ankur,Singh, Anshu,Singh, Neetu,Ghosh, Kaushik
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p. 3108 - 3125
(2020/05/18)
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- Organocatalytic asymmetric vinylogous 1,4-addition of α,α-Dicyanoolefins to chalcones under a bio-based reaction media: Discovery of new Michael adducts with antiplasmodial activity
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The organocatalysed asymmetric vinylogous Michael addition of α,α-dicyanoolefins to α,β-unsaturated aldehydes and ketones have been reported in the last decade, however, chalcones have been poorly explored. Moreover, a considerable part of the publications in this theme still employs undesirable solvents, such as toluene and THF, with concerns related to health and environmental safety. We report herein the use of a bifunctional catalyst derived from a Cinchona alkaloid to perform the enantio- and diastereoselective Michael addition of α,α-dicyanoolefins to chalcones using 2-MeTHF as solvent. The Michael adducts were obtained in moderate to good yields and were evaluated for their antiplasmodial and cytotoxic activity.
- Martelli, Lorena S.R.,Vieira, Lucas C.C.,Paix?o, Márcio W.,Zukerman-Schpector, Julio,de Souza, Juliana O.,Aguiar, Anna Caroline C.,Oliva, Glaucius,Guido, Rafael V.C.,Corrêa, Arlene G.
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supporting information
p. 3530 - 3542
(2019/05/24)
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- Synthesis and evaluation of chalcone and its derivatives as potential anticholinergic agents
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Background: Structural similarity in Chalcone and Pyrazoline brought our intention for the analysis of such compounds. This study involved the synthesis of chalcones and their pyrazoline derivatives and their screening as cholinesterase inhibitors. The newly synthesized compounds were also investigated for their antioxidant potential. Methods: Chalcones were synthesized by well-established methods of synthesis and their structural elucidation was carried out by H-NMR, 13C-NMR, Mass spectrometry and FTIR. For the determination of inhibition potency of synthesized compounds, spectrophotometric method was applied whereas, DPPH free radical scavenging method was used to check the antioxidant ability. Results: Chalcones and their pyrazoline derivatives were synthesized and characterised by 1HNMR, 13C-NMR, Mass spectrometry and FTIR. The compounds were screened for their anti-Alzheimer activity, which exhibited that compounds 1g, 1c and 1h, 1g showed strong inhibitory potency against acetylcholinesterase and butyrylcholinesterase, respectively. DPPH radical scavenging method was applied to check anti-oxidant potential of synthesized compounds and results explored that among all the synthesized compounds only compounds 1c and 1b showed strong scavenging potential. Conclusion: Chalcone and their pyrazoline derivatives were synthesized and screened for their anti-Alzheimer and antioxidant potential. The experimental results of anti-Alzheimer activity were compared with molecular docking studies, which showed that compounds 1g, 1c and 1h, 1g were active against AChE and BChE, respectively. Among the synthesized compounds 1c and 1b were found to be most potent antioxidants. These results suggest that compound 1b, 1c, 1g and 1h may further be explored for further developments.
- Murtaza, Shahzad,Mir, Khoula Zubair,Tatheer, Adina,Ullah, Raja Summe
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p. 322 - 332
(2019/06/20)
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- One-Pot Catalytic Enantioselective Synthesis of 2-Pyrazolines
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A scalable, one-pot, enantioselective catalytic synthesis of 2-pyrazolines from beta-substituted enones and hydrazines is described. Pivoting on a two-stage catalytic Michael addition/condensation strategy, the use of an aldehyde to generate a suitable hydrazone derivative of the hydrazine was found to be key for curtailing background reactivity and tuning the catalyst-controlled enantioselectivity. The new synthetic method is easy to perform, uses a new and readily prepared cinchona-derived bifunctional catalyst, is broad in scope, and tolerates a range of functionalities with high enantioselectivity (up to >99:1 e.r.). The significant scalability of this methodology was demonstrated with the synthesis of more than 80 grams of a pyrazoline product with 89 % catalyst recovery.
- Thomson, Connor J.,Barber, David M.,Dixon, Darren J.
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supporting information
p. 2469 - 2473
(2019/02/01)
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- Studies of NMR Chemical Shifts of Chalcone Derivatives of Five-membered Monoheterocycles and Determination of Aromaticity Indices
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A series of the chalcone derivatives of the five-membered monoheterocyclic compounds, (E)-1-aryl-3-heteroarylpropen-1-ones, were prepared by aldol condensation of the corresponding aldehydes of thiophene, pyrrole, and furan with m- and p-substituted acetophenones. Similar condensation of the acetyl compounds of the heterocycles with m- and p-substituted benzaldehydes gave another series of the chalcone derivatives, (E)-1-heteroaryl-3-arylpropen-1-ones. The 13C chemical shift values (δC) of the chalcone derivatives were determined in order to find if they correlated with the Hammett σ values. A good correlation, especially for the β-C for both series, was found for the 13C chemical shift values (δC) of the chalcone derivatives with the Hammett σ values. The chemical shift values of the β-C of the heterocyclic compounds were plotted against those of the benzene derivatives. The resulting slopes were found to be close to the values of the aromaticity indices.
- Jeong, Eun Jeong,Lee, In-Sook Han
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p. 668 - 673
(2019/07/12)
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- LANTHANIDE COMPLEXES BASED ON TRIETHYLENETETRAMINE-N,N,N',N'',N''',N'''-HEXAACETIC ACID DERIVATIVES
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The present invention relates to a complex comprising at least one lanthanide (Ln) and at least one compound (C) comprising a unit of formula (I) below: said unit of formula (I) being covalently connected to at least one antenna which absorbs at a wavelength ranging from 500 nm to 900 nm.
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Paragraph 0145-0147
(2019/11/11)
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- LANTHANIDE COMPLEXES COMPRISING DENDRIMERS
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The present invention relates to a complex comprising at least one dendrimer and at least one lanthanide, wherein the dendrimer comprises a unit of formula (I) below: in which: C1 is a valence group 4 of formula >N—CH2—CH2—N1, A2 and A3 are groups of formula —(CH2)2—C(O)—NH—(CH2)2—; the unit of formula (I) being connected covalently to at least one antenna which absorbs at a wavelength ranging from 500 nm to 900 nm.
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Paragraph 0108; 0109; 0110
(2019/12/01)
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- Synthesis of 4,5,6,7-tetrahydrobenzoxazol-2-ones by a highly regioselective Diels-Alder cycloaddition of exo-oxazolidin-2-one dienes with chalcones
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The synthesis of novel of 4,5,6,7-tetrahydrobenzoxazol-2-ones is herein reported. They were obtained in moderate to good yields by a highly regio- and stereoselective Diels-Alder cycloaddition of N-substituted exo-oxazolidin-2-one dienes with chalcones or bis-chalcones as dienophiles.
- Mastachi-Loza, Salvador,Ramírez-Candelero, Tania I.,Tapia-Bustamante, Asenet,González-Romero, Carlos,Díaz-Torres, Eduardo,Tamariz, Joaquín,Toscano, Rubén A.,Fuentes-Benítes, Aydeé
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supporting information
p. 1370 - 1374
(2019/04/30)
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- Intermolecular Multiple Dehydrogenative Cross-Couplings of Ketones with Boronic Acids and Amines via Copper Catalysis
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An efficient and versatile oxidative coupling reaction was developed for the synthesis of valuable β-functionalized unsaturated ketones and meta-substituted phenols. In the case of intramolecular reactions, achieving rapid molecular complexity through multiple dehydrogenative couplings is already a well-established strategy. Herein, we report an intermolecular multiple dehydrogenative coupling between ketones and nucleophilic amines or boronic acids using inexpensive copper(I) oxide as a catalyst. This method provides a facile access to highly desirable chemical products such as α,β-unsaturated ketones, enaminones, and synthetically relevant meta-substituted phenols. (Figure presented.).
- Wang, Tianzhang,Chen, Guowei,Lu, Yu-Jing,Chen, Qian,Huo, Yanping,Li, Xianwei
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supporting information
p. 3886 - 3892
(2019/07/19)
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- Regioselective hydrodehalogenation of aromatic α-and β-halo carbonyl compounds by cui in isopropanol
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An operationally efficient and regioselective hydrodehalogenation methodology of aromatic α-and β-halo carbonyl compounds has been developed using CuI in isopropanol at 90 °C under basic condition. The catalytic system effectively dehalogenates chloride, bromide, and iodide groups and af-forded high yield (up to 97 %) as carbonyl compounds. The methodology is environmentally friendly and demonstrates excellent tolerance to a broad range of electronically rich and poor substituents.
- Parveen, Iram,Khan, Danish,Ahmed, Naseem
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p. 759 - 764
(2019/01/09)
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- Acyl/aroyl Meldrum's acid as an enol surrogate for the direct organocatalytic synthesis of α,β-unsaturated ketones
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The operationally simple, robust and straightforward organocatalytic protocol is developed for the synthesis of E-selective α,β-unsaturated ketones. The method utilizes simple and easily accessible starting materials such as Meldrum's acid, carboxylic acid, aldehyde and simple bifunctional amine catalyst. The tandem organocatalytic process utilizes acyl/aroyl Meldrum's acid as an enol surrogate for the effective Doebner-Knoevenagel type condensation reactions. A wide variety of aldehydes, carboxylic acids and base sensitive functional groups are well tolerated under the mild reaction conditions.
- Khopade, Tushar M.,Warghude, Prakash K.,Mete, Trimbak B.,Bhat, Ramakrishna G.
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p. 197 - 200
(2018/12/13)
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- Synthesis of α, β - unsaturated ketone method
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A synthetic method for [alpha],[beta]-unsaturated ketone is a method which catalyzes a primary alconol and a secondary alcohol to oxidize and couple by a supported catalyst. The method includes the steps of adding the primary alconol, the secondary alcohol, an alkali and the catalyst into the mixed solvent mixing water and tert-butyl alcohol; stirring at 0-100 DEG C for 0.5-36 hours under the existence of an oxidizing agent. The yield of [alpha],[beta]-unsaturated ketone can reach 99% in the oxidation coupling reaction system. The synthetic method is environment friendly and has high atom economy and reaction efficiency. Moreover, the synthetic method uses non-noble metal catalyst, so that the production cost is greatly reduced.
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Paragraph 0020
(2019/01/05)
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- Synthesis of chalcones with antiproliferative activity on the SH-SY5Y neuroblastoma cell line: Quantitative Structure–Activity Relationship Models
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Chalcones are a group of molecules with a broad spectrum of biological activities, being especially appealing for their antiproliferative effects on several cancer cell lines. For this reason, we synthesized 23 chalcones with good to excellent yields and assessed their effect on the viability of the SH-SY5Y neuroblastoma cell line and on primary human fibroblasts. The results indicated that 18 of these compounds were more active than 5-fluorouracil in the cancer cell line and one of them was more selective than this reference drug. To identify structural features related to the antiproliferative activity of these compounds, as well as, the selectivity on the cancer cell line, a 2D-QSAR analysis was performed. The QSAR model (q2 = 0.803; r2 = 0.836) showed that lipophilicity (CLogP) is the most important factor to increase their cytotoxicity on the cancer cell line. On the other hand, the selectivity QSAR model (q2 = 0.917; r2 = 0.916) showed that changes in the Mulliken’s charge of the carbonyl group and at the C4’ position in the chalcone core can increase the selectivity for SH-SY5Y cell line compared to normal fibroblasts.
- Mellado, Marco,Madrid, Alejandro,Reyna, Mauricio,Weinstein-Oppenheimer, Caroline,Mella, Jaime,Salas, Cristian O.,Sánchez, Elizabeth,Cuellar, Mauricio
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p. 2414 - 2425
(2018/09/25)
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- The synthesis of chalcones as anticancer prodrugs and their bioactivation in CYP1 expressing breast cancer cells
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Background: Although the expression levels of many P450s differ between tumour and corresponding normal tissue, CYP1B1 is one of the few CYP subfamilies which is significantly and consistently overexpressed in tumours. CYP1B1 has been shown to be active within tumours and is capable of metabolising a structurally diverse range of anticancer drugs. Because of this, and its role in the activation of procarcinogens, CYP1B1 is seen as an important target for anticancer drug development. Objective: To synthesise a series of chalcone derivatives based on the chemopreventative agent DMU-135 and investigate their antiproliferative activities in human breast cancer cell lines which express CYP1B1 and CYP1A1. Method: A series of chalcones were synthesised in yields of 43-94% using the Claisen-Schmidt condensation reaction. These were screened using a MTT assay against a panel of breast cancer cell lines which have been characterised for CYP1 expression. Result: A number of derivatives showed promising antiproliferative activities in human breast cancer cell lines which express CYP1B1 and CYP1A1, while showing significantly lower toxicity towards a non-tumour breast cell line with no CYP expression. Experiments using the CYP1 inhibitors acacetin and α-naphthoflavone provided supporting evidence for the involvement of CYP1 enzymes in the bioactivation of these compounds. Conclusion: Chalcones show promise as anticancer agents with evidence suggesting that CYP1 activation of these compounds may be involved.
- Ruparelia, Ketan C.,Zeka, Keti,Ijaz, Taeeba,Ankrett, Dyan N.,Wilsher, Nicola E.,Butler, Paul C.,Tan, Hoon L.,Lodhi, Sabahat,Bhambra, Avninder S.,Potter, Gerard A.,Arroo, Randolph R.J.,Beresford, Kenneth J.M.
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p. 322 - 332
(2018/06/26)
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- Chalcone and cinnamate synthesis via one-pot enol silane formation-Mukaiyama aldol reactions of ketones and acetate esters
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Aryl alkyl ketones, acetate esters, and acetamides undergo facile one-pot enol silane formation, Mukaiyama aldol addition, and dehydrosilyloxylation in the presence of an amine base and excess trimethylsilyl trifluoromethanesulfonate. The chalcone and cinnamate products are generally recovered in high yield. The relative stoichiometry of the trimethylsilyl trifluoromethanesulfonate and amine base reagents determines whether the reaction yields the β-silyloxy carbonyl product or the α,β-unsaturated carbonyl.
- Downey, C. Wade,Glist, Hadleigh M.,Takashima, Anna,Bottum, Samuel R.,Dixon, Grant J.
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supporting information
p. 3080 - 3083
(2018/07/06)
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- Chalcones and their pyrazine analogs: synthesis, inhibition of aldose reductase, antioxidant activity, and molecular docking study
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Abstract: Chalcones and their pyrazine analogs synthesized by Claisen–Schmidt condensation were tested for inhibition of aldose reductase, which is the key enzyme in the development of secondary diabetic complications. The most active compounds exerted IC50 values within the micromolar scale, and their interactions with the enzyme were described in a molecular docking study. Antioxidant activity of several representative compounds was explored in DPPH (2,2-diphenyl-1-picrylhydrazyl) assay, revealing significant scavenging for 4-hydroxy-substituted derivatives endowed with electron-donating methoxy substituent in position 3 of the ring B. To conclude, the novel chalcones hydroxylated and methoxylated in the B-ring and their pyrazine analogs exhibited significant aldose reductase inhibition activity, albeit lower in comparison with the reference epalrestat. Medium antioxidant activity (not exceeding the antioxidant efficacy of the standard Trolox) was shown by the representative compounds tested.
- Kucerova-Chlupacova, Marta,Dosedel, Martin,Kunes, Jiri,Soltesova-Prnova, Marta,Majekova, Magdalena,Stefek, Milan
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p. 921 - 929
(2018/02/26)
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- Transition-Metal-Free Catalytic Formal Hydroacylation of Terminal Alkynes
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Although hydroacylation is a very useful reaction for producing ketones from aldehydes with 100% atom efficiency, classical Rh-catalyzed hydroacylation presents several problems, including the need for transition metal catalysts, unwanted decarbonylation of aldehydes, and difficulty in regioselectivity control. However, formal hydroacylation utilizing the nucleophilicity of terminal alkynes can avoid these problems. In this work, we have achieved transition-metal-free formal hydroacylation of terminal alkynes using an Mg3Al-CO3-layered double hydroxide as a heterogeneous catalyst. This system was applicable to the efficient synthesis of α,β-unsaturated ketones with various substituents, and the catalyst can be reused without a significant loss of catalytic performance.
- Yatabe, Takafumi,Mizuno, Noritaka,Yamaguchi, Kazuya
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p. 11564 - 11569
(2018/11/23)
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- Dimethylisosorbide (DMI) as a Bio-Derived Solvent for Pd-Catalyzed Cross-Coupling Reactions
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Palladium-catalyzed bond-forming reactions, such as the ?-Suzuki-Miyaura and Mizoroki-Heck reactions, are some of the most broadly utilized reactions within the chemical industry. These reactions frequently employ hazardous solvents; however, to adhere to increasing sustainability pressures and restrictions regarding the use of such solvents, alternatives are highly sought after. Here we demonstrate the utility of dimethyl isosorbide (DMI) as a bio-derived solvent in several benchmark Pd-catalyzed reactions: Suzuki-Miyaura (13 examples, 62-100% yield), Mizoroki-Heck (13 examples, 47-91% yield), and Sonogashira (12 examples, 65-98% yield).
- Wilson, Kirsty L.,Murray, Jane,Sneddon, Helen F.,Jamieson, Craig,Watson, Allan J. B.
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p. 2293 - 2297
(2018/10/20)
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- Indium(III) triflate-catalyzed reactions of AZA-michael adducts of chalcones with aromatic amines: Retro-michael addition versus quinoline formation
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The indium(III) triflate-catalyzed reaction of aza-Michael adducts of chalcones with aromatic amines has been investigated. The Michael adducts derived from substituted anilines and chalcones underwent retro-Michael addition to give the original starting materials, whereas the adducts derived from 1-naphthylamines and chalcones afforded quinolines. A six-membered cyclic transition state has been proposed to explain the retro-Michael addition, while a Povarov mechanism has been put forward to explain the quinoline formation.
- Selvi, Thangavel,Velmathi, Sivan
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p. 4087 - 4091
(2018/04/14)
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- Synthesis and evaluation of modified chalcone based p53 stabilizing agents
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Tumor suppressor protein p53 induces cell cycle arrest and apoptotic cell death in response to various cellular stresses thereby preventing cancer development. Activation and stabilization of p53 through small organic molecules is, therefore, an attractive approach for the treatment of cancers retaining wild-type p53. In this context, a series of nineteen chalcones with various substitution patterns of functional groups including chloro, fluoro, methoxy, nitro, benzyloxy, 4-methyl benzyloxy was prepared using Claisen-Schmidt condensation. The compounds were characterized using NMR, HRMS, IR and melting points. Evaluation of synthesized compounds against human colorectal (HCT116) and breast (CAL-51) cancer cell lines revealed potent antiproliferative activities. Nine compounds displayed GI50 values in the low micromolar to submicromolar range; for example (E)-1-phenyl-3-(3,4,5-trimethoxyphenyl)prop-2-en-1-one (SSE14108) showed GI50 of 0.473 ± 0.043 μM against HCT116 cells. Further analysis of these compounds revealed that (E)-3-(4-chlorophenyl)-1-phenylprop-2-en-1-one (SSE14105) and (E)-3-(4-methoxyphenyl)-1-phenylprop-2-en-1-one (SSE14106) caused rapid (4 and 8-h post-treatment) accumulation of p53 in HCT116 cells similar to its induction by positive control, Nutlin-3. Such activities were absent in 3-(4-methoxyphenyl)propiophenone (SSE14106H2) demonstrating the importance of conjugated ketone for antiproliferative and p53 stabilizing activity of the chalcones. We further evaluated p53 levels in the presence of cycloheximide (CHX) and the results showed that the p53 stabilization was regulated at post-translational level through blockage of its degradation. These chalcones can, therefore, act as fragment leads for further structure optimization to obtain more potent p53 stabilizing agents with enhanced anti-proliferative activities.
- Iftikhar, Sunniya,Khan, Sardraz,Bilal, Aishah,Manzoor, Safia,Abdullah, Muhammad,Emwas, Abdel-Hamid,Sioud, Salim,Gao, Xin,Chotana, Ghayoor Abbas,Faisal, Amir,Saleem, Rahman Shah Zaib
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supporting information
p. 4101 - 4106
(2017/08/22)
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- Efficient synthesis of functionalized olefins by Wittig reaction using Amberlite resin as a mild base
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A convenient procedure for the synthesis of olefins by the reaction of stabilized, semistabilized, and nonstabilized phosphorous ylides with various aldehydes or ketone using Amberlite resin as a mild base is described. Our developed method offers facile and racemization-free synthesis of α,β-unsaturated amino esters and chiral allylic amine. The developed methodology offers mild reaction conditions, high efficiency, and facile isolation of the final products, a practical alternative to known procedures.
- Valkute, Tushar R.,Aratikatla, Eswar K.,Bhattacharya, Asish K.
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p. 581 - 589
(2017/03/15)
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- Bifunctional Thiourea-Catalyzed Stereoablative Retro-Sulfa-Michael Reaction: Concise and Diastereoselective Access to Chiral 2,4-Diarylthietanes
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Owing to the chiral recognition capacity of bifunctional thioureas, a stereoablative retro-sulfa-Michael reaction has been developed. Utilization of a biphasic system enabled us to render the process catalytic. The usefulness of this methodology was further illustrated by the diastereoselective synthesis of all possible stereoisomers of 2,4-diarylthiethanes.
- Bacsó, András,Szigeti, Mariann,Varga, Szilárd,Soós, Tibor
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p. 429 - 439
(2016/12/24)
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- Design, synthesis, topoisomerase I & II inhibitory activity, antiproliferative activity, and structure-activity relationship study of pyrazoline derivatives: An ATP-competitive human topoisomerase IIα catalytic inhibitor
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A series of pyrazoline derivatives (5) were synthesized in 92-96% yields from chalcones (3) and hydrazides (4). Subsequently, topo-I and IIα-mediated relaxation and antiproliferative activity assays were evaluated for 5. Among the tested compounds, 5h had
- Ahmad, Pervez,Woo, Hyunjung,Jun, Kyu-Yeon,Kadi, Adnan A.,Abdel-Aziz, Hatem A.,Kwon, Youngjoo,Rahman, A.F.M. Motiur
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p. 1898 - 1908
(2016/04/05)
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- Novel pyrazoline derivatives and the use thereof
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The present invention relates to a novel pyrazoline derivative compound, a pharmaceutically acceptable salt thereof, and a pharmaceutical composition for preventing or treating cancer, containing the pyrazoline derivative compound or the pharmaceutically
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-
Paragraph 0101; 0103-0104; 0107
(2016/12/01)
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- 2,4,5-Trisubstituted thiazole derivatives as HIV-1 NNRTIs effective on both wild-type and mutant HIV-1 reverse transcriptase: Optimization of the substitution of positions 4 and 5
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In our previous work, novel 2,4,5-trisubstituted thiazole derivatives (TSTs) were synthesized, and their activities were evaluated against HIV-1 reverse transcriptase. Some interesting results were obtained, which led us to a new discovery regarding these TSTs. In the present study, 21 new 2,4,5-trisubstituted thiazole derivatives were rationally designed and synthesized as HIV-1 non-nucleoside reverse transcriptase inhibitors (NNRTIs) in accordance with our previous study. Among the synthesized target compounds, compounds 14, 16, 17, and 19 showed more potent inhibitory activities against HIV-1 with an IC50value of 0.010?μM. Compounds 4, 9, 10, 11, 13 and 16 were further tested on nine NNRTI-resistant HIV-1 strains, and all of these compounds exhibited inhibitory effects. A molecular docking study was conducted, and the results showed a consistent and stable binding mode for the typical compounds. These results have provided deeper insights and SAR of these types of NNRTIs.
- Xu, Zhongliang,Guo, Jiamei,Yang, Ying,Zhang, Mengdi,Ba, Mingyu,Li, Zhenzhong,Cao, Yingli,He, Ricai,Yu, Miao,Zhou, Hua,Li, Xiaoxi,Huang, Xiaoshan,Guo, Ying,Guo, Changbin
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supporting information
p. 309 - 316
(2016/08/04)
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- Carbon-carbon bond formation in acid deep eutectic solvent: Chalcones synthesis: Via Claisen-Schmidt reaction
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One of the most studied properties of novel organic solvents is represented by their use as media for many chemical reactions. In this field Ionic Liquids (ILs) and more recently Deep Eutectic Solvents (DESs) have been playing significant roles for their smart properties. DESs are increasing their relevance thanks to their low toxicity, and because of their simple and cheap preparation that can be carried out by simply mixing two compounds. In this work we present the studies of the use of an acid DES obtained from 3-(cyclohexyldimethylammonio)propane-1-sulfonate and (1S)-(+)-10-camphorsulfonic acid (SB3-Cy/CSA) as reaction media and catalyst for carbon-carbon bond formation reaction via Claisen-Schmidt condensation. This powerful and widely used aldol condensation was performed without the use of any catalysts that are usually needed in this reaction, because of the presence of acid CSA in the DES components. We synthesised fourteen substituted chalcones from benzaldehydes and substituted benzaldehydes in combination with acetophenone and substituted acetophenones as probe reactions. The advantages of the use of this DES in this relevant reaction are represented by: the green properties of the media and its low toxicity; the absence of harmful acids to catalyse the aldol condensation because of the camphorsulfonic acid composing the DES mixture; the recycling and the re-use of the DES in subsequent reaction cycles; the mild conditions and the excellent conversions and yields observed.
- Tiecco, Matteo,Germani, Raimondo,Cardellini, Fabio
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p. 43740 - 43747
(2016/05/24)
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- Chemoselective Ketone Synthesis by the Addition of Organometallics to N-Acylazetidines
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A general and highly chemoselective method for the synthesis of ketones by the addition of organometallics to N-acylazetidines via stable tetrahedral intermediates is reported for the first time. The transformation is characterized by its wide substrate scope and exquisite selectivity for the ketone products even when a large excess of nucleophilic reagents is used. Even of broader interest is the use of N-acylazetidines as bench-stable, readily available amide acylating reagents, in which the reactivity is controlled by amide pyramidalization and strain of the four-membered ring to afford synthetically valuable building blocks.
- Liu, Chengwei,Achtenhagen, Marcel,Szostak, Michal
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supporting information
p. 2375 - 2378
(2016/06/09)
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- Catalyzed Claisen-Schmidt reaction by protonated aluminate mesoporous silica nanomaterial focused on the (E)-chalcone synthesis as a biologically active compound
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The mesoporous silica structure (MSN) was synthesized using the sol-gel method followed by aluminum grafting and protonation and was then denoted as HAlMSN (Si/Al = 18.9). N2 physisorption confirmed the mesoporous structure with a pore diameter of 3.38 nm. 27Al NMR showed the presence of framework and extra-framework aluminum structures, which led to the formation of strong Lewis and Br?nsted acidic sites. HAlMSN catalyzed the synthesis of (E)-chalcones through the Claisen-Schmidt reaction. Chalcone derivatives have been applied as biologically active compounds with anti-cancer, anti-inflammatory and diuretic pharmacological activities. The products were obtained via reactions on the protonic acid sites of HAlMSN. The significant advantages of this reaction are high yield, easy work up, short reaction time and also compatibility with various organic solvents. The products were obtained in an excellent conversion of 97% at 298 K. The results show that the electron donating substituents exhibit higher conversion in comparison to electron withdrawing substituents. The stability of the catalyst was investigated by reusing it five times for (E)-chalcone production and there was only a slight decrease in its catalytic activity. The highest product of (E)-chalcone was observed with a 1:2 molar ratio of benzaldehyde/acetophenone. A comparative study in chalcone synthesis using the heterogeneous catalysts demonstrated that HAlMSN has a significantly high activity at low temperature.
- Sazegar, Mohammad Reza,Mahmoudian, Shaya,Mahmoudi, Ali,Triwahyono, Sugeng,Jalil, Aishah Abdul,Mukti, Rino R.,Nazirah Kamarudin, Nur H.,Ghoreishi, Monir K.
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p. 11023 - 11031
(2016/02/05)
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- Phosphorous Acid Promoted Hydration-Condensation of Aromatic Alkynes with Aldehydes Affording Chalcones in an Oil/Water Two-Phase System
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A simple and environmentally benign method was developed for the synthesis of chalcones in high to excellent yields by a phosphorous acid promoted alkyne-aldehyde hydration-condensation in an oil/water two-phase system. The method is the first efficient protocol for the preparation of chalcones that is mediated by a simple Bronsted acid in a two-phase system.
- Zhou, Yongbo,Li, Zhongwen,Yang, Xiao,Chen, Xiulin,Li, Mei,Chen, Tieqiao,Yin, Shuang-Feng
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p. 231 - 237
(2016/01/12)
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- Iron-facilitated oxidative radical decarboxylative cross-coupling between α-oxocarboxylic acids and acrylic acids: An approach to α,β-unsaturated carbonyls
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The first Fe-facilitated decarboxylative cross-coupling reaction between α-oxocarboxylic acids and acrylic acids in aqueous solution has been developed. This transformation is characterized by its wide substrate scope and good functional group compatibility utilizing inexpensive and easily accessible reagents, thus providing an efficient and expeditious approach to an important class of α,β-unsaturated carbonyls frequently found in bioactive compounds. The synthetic potential of the coupled products is also demonstrated in subsequent functionalization reactions. Preliminary mechanism studies suggest that a free radical pathway is involved in this process: the generation of an acyl radical from α-oxocarboxylic acid via the excision of carbon dioxide followed by the addition of an acyl radical to the α-position of the double bond in acrylic acid then delivers the α,β-unsaturated carbonyl adduct through the extrusion of another carbon dioxide.
- Jiang, Qing,Jia, Jing,Xu, Bin,Zhao, An,Guo, Can-Cheng
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p. 3586 - 3596
(2015/04/22)
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- Green synthesis of chalcones and microbiological evaluation
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A green method was developed for the synthesis of chalcones using glycerin as solvent. Subsequently, the potential microbiology activity of these molecules was evaluated by testing them against the Gram-positive bacteria Staphylococcus aureus (S. aureus) ATCC 19095 and Enterococcus faecalis (E. faecalis) ATCC 4083, the Gram-negative bacteria Escherichia coli (E. coli) ATCC 29214 and Pseudomonas aeruginosa (P. aeruginosa) ATCC 9027, and the fungus Candida albicans (C. albicans), which includes ATCC 62342 and three clinical strains of C. albicans from human oral cavities. The results showed that some chalcones exhibited moderate inhibitory activity, the most prominent being those acting against the fluconazole-resistant strains of C. albicans.
- Ritter, Marina,Martins, Rosiane M.,Rosa, Silvana A.,Malavolta, Juliana L.,Lund, Rafael G.,Flores, Alex F. C.,Pereira, Claudio M.P.
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p. 1201 - 1210
(2015/06/16)
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