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دسترسی آزاد مقاله
1 - Fe3O4@SiO2/Kit-6 as a Magnetic Nano-Catalyst for the Synthesis of New Coumarin Fused Pyrrole Derivatives
Elham Sadr Hossein Anaraki-Ardakani Soheil Sayyahi Farzaneh HosseiniA series of new coumarin fused pyrrole derivatives were successfully synthesized through a one-pot multi-component reaction between 4-aminocoumarin, aryl glyoxals, and amides (thioacetamide) in the presence of Fe3O4@SiO2/Kit-6 in ethanol under reflux conditions. Further چکیده کاملA series of new coumarin fused pyrrole derivatives were successfully synthesized through a one-pot multi-component reaction between 4-aminocoumarin, aryl glyoxals, and amides (thioacetamide) in the presence of Fe3O4@SiO2/Kit-6 in ethanol under reflux conditions. Further advantages to this synthesis include excellent yields, mild reaction conditions, atom economy, environment-friendly, magnetically reusable catalyst, and no need for chromatographic separations. پرونده مقاله -
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2 - BF3-SiO2 Nanoparticles: An Efficient Catalyst for the Multi-Component Synthesis of 3-(α-aroylamido) 4-hydroxycoumarin Derivatives in Water
Mona Arfavi-Safari Hossein Anaraki-Ardakani Rashid Badri Elham TahanpesarA green and efficient one-pot three component reaction of 4-hydroxycoumarin or 1,3-dimethylbarbutyric acid, aryl glyoxals and amides (thioacetamide) has been developed in the presence of BF3- SiO2 nanoparticles in water. This method has several advantages such as high t چکیده کاملA green and efficient one-pot three component reaction of 4-hydroxycoumarin or 1,3-dimethylbarbutyric acid, aryl glyoxals and amides (thioacetamide) has been developed in the presence of BF3- SiO2 nanoparticles in water. This method has several advantages such as high to excellent product yields in short reaction time, atom economy, environment friendly, reusable catalyst and no need for chromatographic separations. پرونده مقاله -
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3 - Promoted Preparation of Aminophosphonate and Functionalized Coumarins Derivatives as Key Constituent of Many Pharmaceutical Compounds
Helia Mohammadi Bita Mohtat Mehran KordtabarThe reaction between trialkyl phosphites with dialkyl actylenedicarboxylates in the presence of 2-hydroxyquinoline (2-quinolinol) leads to β-aminophsphonates derivatives which they have many applications in medicinal chemistry. When the reaction was performed by tr چکیده کاملThe reaction between trialkyl phosphites with dialkyl actylenedicarboxylates in the presence of 2-hydroxyquinoline (2-quinolinol) leads to β-aminophsphonates derivatives which they have many applications in medicinal chemistry. When the reaction was performed by triphenylphosphite, a new pyrano quinoline compounds were obtained in fairly good yields. These compounds also provide biologically interesting. All roducts were established by IR, NMR (1H,13C and31P),mass spectroscopy and elemental analysis. پرونده مقاله -
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4 - An Efficient Synthesis of Benzylamino Coumarin Derivatives via Three-component Coupling of 4-hydroxycoumarin, Aromatic Aldehyde and Cyclic Secondary Amine Catalyzed by CuO Nanoparticles
Hossein Anaraki-Ardakani Behrooz Mirza Nader MokhtarianA green and efficient one-pot synthesis of benzylamino coumarin derivatives was conducted by a three-component condensation of 4-hydroxycoumarin, cyclic secondary amine, and aromatic aldehyde in the presence of CuO nanoparticles (NPs) as a heterogeneous catalyst in w چکیده کاملA green and efficient one-pot synthesis of benzylamino coumarin derivatives was conducted by a three-component condensation of 4-hydroxycoumarin, cyclic secondary amine, and aromatic aldehyde in the presence of CuO nanoparticles (NPs) as a heterogeneous catalyst in water at room temperature. پرونده مقاله -
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5 - Application of Triphenylphosphine for Facile Synthesis of Several Alkyl Acrylates from Heterocyclic Phenols
Bita Mohtat Hoorieh Djahaniani7-Hydroxycoumarine undergoes a smooth reaction with alkyl propiolates in the presence of triphenylphosphine (15 mol%) to produce the corresponding alkyl (E)-3-((2-oxo-2H-chromen- 7-yl)oxy)acrylate in good yields. When the reaction was performed by 3-hydroxyquinoline sim چکیده کامل7-Hydroxycoumarine undergoes a smooth reaction with alkyl propiolates in the presence of triphenylphosphine (15 mol%) to produce the corresponding alkyl (E)-3-((2-oxo-2H-chromen- 7-yl)oxy)acrylate in good yields. When the reaction was performed by 3-hydroxyquinoline similar alkyl acrylates were obtained. پرونده مقاله -
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6 - Chemical composition of <i>Leplaea mayombensis</i> (Pellegrin) Staner
Djeukeu Charlie Hermine Laure Djomkam Maza Kenmogne Ariane Sewald Norbert Wansi Duplex Vardamides CatherineOne new coumarinolignan, cleomiscosin F (1) along with ten known compounds namely 3,4-secotirucalla-4(28),7,24-trien-21-hydroxy-21,23-epoxy-3-oic acid (2), 3,4-secotirucalla-4(28),7,24-trien-3,21-dioic acid (3),ceramid A (4),ceramid B (5), mayombensin (6),aridanin (7), چکیده کاملOne new coumarinolignan, cleomiscosin F (1) along with ten known compounds namely 3,4-secotirucalla-4(28),7,24-trien-21-hydroxy-21,23-epoxy-3-oic acid (2), 3,4-secotirucalla-4(28),7,24-trien-3,21-dioic acid (3),ceramid A (4),ceramid B (5), mayombensin (6),aridanin (7), stigmasterol and β-sitosterol and their glucosides were isolated from the seeds and roots of Leplaea mayombensis (Meliaceae).Thestructures of the compounds were elucidated based on the interpretation of their spectroscopic data. Some of the isolated compounds (3, 4 and 5) were tested in vitro against bacteria strains Escherichia coli, Bacillus subtilis, Pseudomonas agarici, and Micrococcus luteus. Compound 3 displayed good activity against Bacillus subtilis, Micrococcus luteus, and Pseudomonas agarici with MIC values of 1.7, 2.3 and 9.8µM, respectively; while compound 4 showed significant activity against Micrococcus luteus with MIC value of 11.9µM. پرونده مقاله -
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7 - Phytochemical studies of <i>Tetrataenium nephrophyllum</i> and anti-acetylcholinesterase activities
Mehdi Abbasi Marzie Omrani Leila Raiatparvar Malieki Ali Sonboli Samad Nejad EbrahimiTetrataenium nephrophyllum belonging to the Apiaceae family grows widely in the West Azerbaijan province of Northwestern Iran. It is an aromatic plant that has been used as food spices by local people. In this research work, the phytochemical composition of n-hexane ext چکیده کاملTetrataenium nephrophyllum belonging to the Apiaceae family grows widely in the West Azerbaijan province of Northwestern Iran. It is an aromatic plant that has been used as food spices by local people. In this research work, the phytochemical composition of n-hexane extract from the aerial parts of this plant has been investigated. The fractionation of the n-hexane extract by normal phase column chromatography resulted in the isolation, purification, and identification of five compounds. The structural elucidation was accomplished by extensive spectroscopic methods, including 1D and 2D NMR experiments (1H-NMR, H-H-COSY, HSQC, HMBC, and NOESY) as well as ESI-MS analysis. The isolated compounds were 5-geranyloxycoumarin (1), isobergapten (2), pimpinellin (3), β-sitosterol (4) and dammara- 20,23-dien-3β,25-diol. The acetylcholinesterase inhibitory activity of the isolated compound was evaluated by experimental and molecular docking methods. Compound 3 showed the best acetylcholinesterase inhibitory with an IC50 value of 0.208 μM and docking score of -7.5 kcal/mol. پرونده مقاله -
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8 - مقایسه پایداری حرارتی رزین های اپوکسی پخت شده با مشتقات بنزیلیدین بیس-(4-هیدروکسیکومارین)
قاسم راه پیما جلیل خضریدر این تحقیق، برای تهیه رزین اپوکسی با کارایی بالا و پایداری حرارتی عالی از مشتقات بنزیلیدین بیس-(4-هیدروکسی کومارین) به عنوان عامل پخت استفاده شد. برای این منظور 4 مشتق بنزیلیدین بیس 4-هیدروکسی کومارین با استفاده از کاتالیست نانوکامپوزیت پلیمری 2–آمینو فنول/طارون چکیده کاملدر این تحقیق، برای تهیه رزین اپوکسی با کارایی بالا و پایداری حرارتی عالی از مشتقات بنزیلیدین بیس-(4-هیدروکسی کومارین) به عنوان عامل پخت استفاده شد. برای این منظور 4 مشتق بنزیلیدین بیس 4-هیدروکسی کومارین با استفاده از کاتالیست نانوکامپوزیت پلیمری 2–آمینو فنول/طارونه نخل سنتز گردید. به منظور بررسی ریخت شناسی رزین اپوکسی پخت شده از روش میکروسکوپ الکترونی روبشی (SEM) استفاده شد. مقایسه پارامترهای دمای شروع تخریب، بازده کربن باقیمانده و پارامترهای سینتیکی برای ارزیابی پایداری حرارتی رزین اپوکسی پخت شده با استفاده از آنالیز وزن سنجی حرارتی(TGA) انجام شد. نتایج نشان داد که رزین اپوکسی پخت شده با مشتق 3و'3-(4-نیترو بنزیلیدین)- بیـس-(4-هیدروکسیکومارین) دمای شروع تخریب و بازده کربن بالاتری نسبت به سایر مشتقات دارد. پس از مشتق 4-نیترو به ترتیب مشتقات دارای 4-کلرو، 4- فلوئورو و 4-متیل، پایداری حرارتی بالاتری دارند. بنابراین می توان گفت که گروه نیترو پایداری حرارتی بالاتری را نسبت به کلر، فلوئور و متیل برای رزین اپوکسی پخت شده فراهم کرده است. مشتقات بنزیلیدین 4-هیدروکسی کومارین به دلیل دارابودن حلقه های آروماتیک، پایداری حرارتی بالایی را برای رزین اپوکسی پخت شده به ارمغان می آورند. پرونده مقاله -
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9 - Synthesis of new coumarin based acetohydrazones, their correspounding oxadiazoles and oxadiazolines, and the investigation of their antibacterial activity
Narjes Baharvand Enayatollah Mottaghinejad Mohsen Sargordan Fardarani Hosseini DoustHere we provide a report on the synthesis, structural recognition and tautomeric behavior of a new series of coumarin-based hydrazide-hydrazones (4-methylcoumarin-7-yl-oxymethyl arylaldehyde acetohydrazones) and their 1,3,4- oxadiazoline and oxadiazole derivatives. The چکیده کاملHere we provide a report on the synthesis, structural recognition and tautomeric behavior of a new series of coumarin-based hydrazide-hydrazones (4-methylcoumarin-7-yl-oxymethyl arylaldehyde acetohydrazones) and their 1,3,4- oxadiazoline and oxadiazole derivatives. The final products were tested for antibacterial activity on both Gram-negative and Grampositive bacteria. Both types of hydrogen, the hydrazone N-H and methylene protons can take part in tautomeric isomerization equilibrium. The synthesis of 1,3,4-oxadiazoles and oxadiazoline bearing coumarin ring was conducted for inferring the isomerization-tautomerization of their hydrazone precursors According to the NMR investigation, We found that, the amide-iminol tautomerization is more probable than keto-enol one. It was further explained via converting the hydrazones to the corresponding 1,3,4-oxadiazoles and oxadiazolines based on the modified procedures. All the synthesized oxadiazoles and oxadiazolines have antibacterial effect on Gram-negative bacteria with respect to Gram-positive bacteria. The active ingredient of the synthesized derivative 8 has the best effect on both Gram-negative and Gram-positive bacteria. پرونده مقاله -
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10 - Triphenylphosphine mediated synthesis of functionalized aryl-vinyl ethers from7-hydroxy coumarin and methyl acetylene carboxylate
Delaram Abdolahi Bita Mohtat7-hydroxy coumarin undergoes neutral conditions with alkyl propiolates in the presence of triphenylphosphine, and bysubstituation the corresponding aryl vinyl ethers was obtained in good yields7-hydroxy coumarin undergoes neutral conditions with alkyl propiolates in the presence of triphenylphosphine, and bysubstituation the corresponding aryl vinyl ethers was obtained in good yields پرونده مقاله -
دسترسی آزاد مقاله
11 - Salicylic acid an efficient organocatalyst for synthesis of coumarins
Rushikesh Mane Pramod KulkarniaVarious substituted coumarins were synthesized in high yield and purity by direct reaction of substituted phenol and β-keto esters in the presence of a catalytic amount of salicylic acid under solvent-free conditions. This method is simple, cost-effective, short re چکیده کاملVarious substituted coumarins were synthesized in high yield and purity by direct reaction of substituted phenol and β-keto esters in the presence of a catalytic amount of salicylic acid under solvent-free conditions. This method is simple, cost-effective, short reaction time, simple work-up procedure, and avoid the use of transition metals. پرونده مقاله -
دسترسی آزاد مقاله
12 - AlCl3 supported on nano silica as an efficient catalyst for the preparation of coumarin
Leila Sarami Elham TahanpesarThe Pechmann condensation has been used as a simple and efficient method for the preparation of coumarin derivatives, which phenols and ethyl acetoacetate were reacted in the presence of AlCl3 supported on nano silica as an efficient catalyst at 110 oC under solvent fre چکیده کاملThe Pechmann condensation has been used as a simple and efficient method for the preparation of coumarin derivatives, which phenols and ethyl acetoacetate were reacted in the presence of AlCl3 supported on nano silica as an efficient catalyst at 110 oC under solvent free condition to form products with good to excellent yield (55 -90%), which are identified by spectroscopic method ( FT-IR, NMR) and melting points and compared with reference samples. پرونده مقاله -
دسترسی آزاد مقاله
13 - AlCl3 supported on nano silica as an efficient catalyst for the preparation of coumarin
Leila Sarami Elham TahanpesarThe Pechmann condensation has been used as a simple and efficient method for the preparation of coumarin derivatives, which phenols and ethyl acetoacetate were reacted in the presence of AlCl3 supported on nano silica as an efficient catalyst at 110 oC under solvent fre چکیده کاملThe Pechmann condensation has been used as a simple and efficient method for the preparation of coumarin derivatives, which phenols and ethyl acetoacetate were reacted in the presence of AlCl3 supported on nano silica as an efficient catalyst at 110 oC under solvent free condition to form products with good to excellent yield (55 -90%), which are identified by spectroscopic method ( FT-IR, NMR) and melting points and compared with reference samples. پرونده مقاله -
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14 - Ultrasonic-assisted Synthesis of New Generation of Coumarins
Lia KarimianA convenient and efficient procedure for synthesis of Bis(4-HydroxyCoumarin) derivatives has been developed by a simple one-pot, one step ultrasonic-assisted reaction to produce Bis(4-HydroxyCoumarins) in room temperature. The present methodology offers several advantag چکیده کاملA convenient and efficient procedure for synthesis of Bis(4-HydroxyCoumarin) derivatives has been developed by a simple one-pot, one step ultrasonic-assisted reaction to produce Bis(4-HydroxyCoumarins) in room temperature. The present methodology offers several advantages, such as a simple procedure with an easy work-up, short reaction times, high yields, and the absence of any volatile and hazardous organic solvents. پرونده مقاله -
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15 - Green synthesis of naphthiridinone using multicomponent reaction of Melderumʼs acid and 4-aminoquinoline-2-one
Seyyed Jalal Shams Najafi Maryam Ghazvini Atefeh NavabiAn efficient synthesis of naphthiridinone derivatives via reaction of 4-aminoquinoline-2-one, Melderum acid and ketones under solnent free conditions and room temperatureis described.An efficient synthesis of naphthiridinone derivatives via reaction of 4-aminoquinoline-2-one, Melderum acid and ketones under solnent free conditions and room temperatureis described. پرونده مقاله -
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16 - (Diacetoxyiodo)benzene (DIB) catalyzed green and efficient synthesis of biscoumarin derivatives in aqueous media
Amit Waghmare Shivaji Pandit(Diacetoxyiodo)benzene has been used as an efficient catalyst for an improved and rapid one-pot synthesis of biscoumarin derivatives in excellent yield under reflux condition using water as a environmentally benign reaction medium. This aqua mediated Knoevenagel condens چکیده کامل(Diacetoxyiodo)benzene has been used as an efficient catalyst for an improved and rapid one-pot synthesis of biscoumarin derivatives in excellent yield under reflux condition using water as a environmentally benign reaction medium. This aqua mediated Knoevenagel condensation of various aromatic and hetero-aromatic aldehydes with 4-hydroxycoumarin using catalytic amount of (diacetoxyiodo)benzene devoid the route of expensive, corrosive reagents and toxic solvents. Along with the routine aldehydes, the aldehydes like aryl-sulphonyloxybenzaldehyde, aryl-carbonyloxybenzaldehyde also leads to the product under the reaction conditions. High yields, shorter reaction times, one pot condensation, operational simplicity, easy work-up, purification of products by non-chromatographic methods are some additional features of this method. پرونده مقاله -
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17 - Synthesis of 4-(trifluoromethyl) coumarins using nano sulfated-titania as solid acid catalyst under solvent-free conditions
Mona Hosseini-Sarvari Sepideh Najafvand-DerikvandiNano sulfated titania was tested as solid acid heterogeneous catalyst for the synthesis of 4-(Trifluoromethyl) coumarin and coumarin derivatives under solvent-free condition. Factorial design evidenced a positive effect of reaction temperature, amount of catalyst, and s چکیده کاملNano sulfated titania was tested as solid acid heterogeneous catalyst for the synthesis of 4-(Trifluoromethyl) coumarin and coumarin derivatives under solvent-free condition. Factorial design evidenced a positive effect of reaction temperature, amount of catalyst, and solvents. This nano-sized sulfated titania has been prepared by a sol-gel hydrothermal process. The prepared sulfated titania showed high catalytic activity in the synthesis of 4-(Trifluoromethyl) coumarin and coumarin derivatives. This method is of great value because of its environmentally benign character, easy handling, high yields, convenient operation, and green. FT-IR studies show that the catalyst can be reused for acylation without loss of catalytic activity. پرونده مقاله -
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18 - Ecofriendly synthesis of biscoumarin derivatives catalyzed by EDTA-modified magnetic animal bone meal nanoparticles in water
Ahmad Reza Momeni Sadegh BakhtiarIn this research, magnetic animal bone meal nanoparticles functionalized with ethylenediaminetetraacetic acid (Fe3O4@ABM-EDTA) is reported as a green recyclable catalyst that catalyzed synthesis of biscoumarin derivatives in water. The catalyst was characterized by the چکیده کاملIn this research, magnetic animal bone meal nanoparticles functionalized with ethylenediaminetetraacetic acid (Fe3O4@ABM-EDTA) is reported as a green recyclable catalyst that catalyzed synthesis of biscoumarin derivatives in water. The catalyst was characterized by the Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), differential thermogravimetric (DTG), scanning electron microscope (SEM) and X-ray diffraction (XRD). This study has demonstrated that Fe3O4@ABM-EDTA can act as an efficient catalyst for synthesis of biscoumarines in the presence of water as solvent at reflux conditions. A wide range of aldehydes could react with 2-hydroxycoumarin and give biscoumarin derivatives in excellent yields. Moreover, Fe3O4@ABM-EDTA was magnetically recovered and reused for five cycles without any significant loss of efficiency. پرونده مقاله -
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19 - An efficient synthesis of α,α'-benzylidene bis(4-hydroxycoumarin) derivatives catalyzed by Tl2O3 nanoparticles
Mohammad Reza NazarifarIn this work, we attempted to synthesize thallium (III) oxide nano structures by direct thermal decomposition using thallium I phenylsuccinic acid coordination polymer [Tl(PsucH)]n as a precursor. Also, Tl2O3 nanoparticles have been characterized by scanning electron mi چکیده کاملIn this work, we attempted to synthesize thallium (III) oxide nano structures by direct thermal decomposition using thallium I phenylsuccinic acid coordination polymer [Tl(PsucH)]n as a precursor. Also, Tl2O3 nanoparticles have been characterized by scanning electron microscopy (SEM), X-Ray powder diffraction (XRD) and IR spectroscopy and then we report a simple and efficient method for the synthesis of α,α'-benzylidene bis(4-hydroxycoumarin) derivatives by aromatic aldehyde and 4-hydroxycoumarin by using Tl2O3 nanoparticles in H2O/EtOH at room temperature. A wide spectrum of functional groups, were tolerated in the developed protocol. The target molecules were obtained in good to excellent yield applying the current method. The catalyst can be recover for the subsequent reactions and reused without loss of activity. پرونده مقاله -
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20 - Brønsted acidic ionic liquid as the efficient and reusable catalyst for synthesis of coumarins via Pechmann condensation under solvent-free conditions
Abdol Reza Hajipour Nafisehsadat Sheikhan Mohammad Ali Alaei Amin ZareiA mild and efficient method has been developed for the preparation of substituted coumarins from reaction of various phenols with different β-ketoesters via Pechmann condensation in the presence of Brønsted acidic ionic liquid (N-(4-sulfonic acid) butyl trie چکیده کاملA mild and efficient method has been developed for the preparation of substituted coumarins from reaction of various phenols with different β-ketoesters via Pechmann condensation in the presence of Brønsted acidic ionic liquid (N-(4-sulfonic acid) butyl triethylammonium hydrogen sulfate) as an effective catalyst under solvent-free conditions. Different phenols reacted with ethyl acetoacetate to produce the corresponding substituted coumarins in high to excellent yields and short reaction times. Moreover, [TEBSA][HSO4] has been used as an effective green catalyst for the synthesis of coumarin derivatives under solvent-free conditions. Using the relatively non-toxic (halogen-free) and reusable Brønsted acidic ionic liquid, high catalytic efficiency, high yields, short reaction times and straightforward work-up are advantages of this protocol. پرونده مقاله -
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21 - Melamine trisulfonic acid: An efficient and recyclable solid acid catalyst for the green synthesis of Biscoumarin derivatives
Nasir Iravani Mosadegh Keshavarz Maryam Mousavi Mojtaba BaghernejadA novel catalytic synthesis of 3,3'-(arylmethylene)-bis-(4-hydroxy-2H-chromene-2-one) derivatives from a tandem condensation reaction of 4-hydroxycoumarin and aromatic aldehydes has been developed. The reaction occurs in water in the presence of Melamine trisulfonic aci چکیده کاملA novel catalytic synthesis of 3,3'-(arylmethylene)-bis-(4-hydroxy-2H-chromene-2-one) derivatives from a tandem condensation reaction of 4-hydroxycoumarin and aromatic aldehydes has been developed. The reaction occurs in water in the presence of Melamine trisulfonic acid as catalyst to give the corresponding products in good to high yields. This green approach has several advantages such as short reaction times, clean reaction profiles, and simple experimental and workup procedures. Moreover, the catalyst can be easily recovered by filtration and used at least seven times with only slight reduction in its catalytic activity. The results of the presented protocol in comparison with the different available catalysts in condensation reaction of benzaldehyde with 4-Hydroxycoumarin show that MTSA presented better results due to the structure of MTSA. پرونده مقاله -
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22 - A green protocol for synthesis of pyran annulated hetrocyclic systems using Na2SO4 as an efficient catalyst
Malek Taher Maghsoodlou Amin Masoumnia Mir Rasul Mousavi Nourollah Hazeri Jasem Aboonajmi Sayyed Mostafa Habibi-Khorasani Shiva KiaeeNa2SO4 as an inexpensive and effective catalyst has provided a green protocol for the synthesis of tetrahydrobenzo[b]pyran, pyrano[2,3-d]pyrimidinone and dihydropyrano[3,2c]chromene derivatives from the three-component domino reaction of aromatic aldehydes and malononit چکیده کاملNa2SO4 as an inexpensive and effective catalyst has provided a green protocol for the synthesis of tetrahydrobenzo[b]pyran, pyrano[2,3-d]pyrimidinone and dihydropyrano[3,2c]chromene derivatives from the three-component domino reaction of aromatic aldehydes and malononitrile with 4-hydroxycoumarin/ dimedone/ barbituric acid in ethanol/water as a mixture of solvent that, this mixture entirely is green solvent. Products could simply be separated from the catalyst. Using neutral and mild conditions, short reaction time, environmentally benign procedure, high to excellent yields of the products and easy work-up without using column chromatography are the advantages of this method. By virtue of these advantages, sodium sulfate can be used as catalyst in the organic transformations. پرونده مقاله -
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23 - L-Proline catalyzed synthesis of Betti bases and biscoumarin derivatives
Samaneh Zahiri Masoud Mokhtary Mogharab TorabiThe direct three component modified Mannich reaction via condensation of aldehydes, 2-naphthol or 2,7-naphthalendiol and piperidine to generate Betti bases has been carried out over L-proline (20 mol%) with high efficiency under solvent free conditions at 70 OC. Also, t چکیده کاملThe direct three component modified Mannich reaction via condensation of aldehydes, 2-naphthol or 2,7-naphthalendiol and piperidine to generate Betti bases has been carried out over L-proline (20 mol%) with high efficiency under solvent free conditions at 70 OC. Also, the reaction of aromatic aldehyde and 4-hydroxycoumarin in the presence of L-proline (20 mol%) in the ethanol under reflux conditions, lead to biscoumarin derivatives پرونده مقاله -
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24 - Multi-component, one-pot, aqueous media preparation of dihydropyrano[3, 2-c]chromene derivatives over MgO nanoplates as an efficient catalyst
Majid Ghashang Syed Sheik Mansoor Leila Shams Solaree Ali Sharifian-esfahaniRed pine leafs were applied for the green method preparation of MgO nano-plates. The MgO nano-plates were used for the one-pot synthesis of dihydropyrano [3,2-c] chromene derivatives. This procedure is very simple and affords excellent yields. MgO nanoplates were synthe چکیده کاملRed pine leafs were applied for the green method preparation of MgO nano-plates. The MgO nano-plates were used for the one-pot synthesis of dihydropyrano [3,2-c] chromene derivatives. This procedure is very simple and affords excellent yields. MgO nanoplates were synthesized via a simple precipitation method with the using of an extract solution of red pine leaves. The XRD pattern shows a cubic phase ofMgO . Field Emission Scanning Electronic Microscopy (FE-SEM) shows clearly that the surface of the as-prepared MgO nano-plates have a homogeneous microstructure made up of layers of various sizes and forms. The plates form irregular grains with a lateral size of 40-110 nm. پرونده مقاله -
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25 - Polyvinylpolypyrrolidone supported antimony(III) chloride (PVPP-SbCl3): An efficient catalyst for the synthesis of chromenylphenylpropanones
Vahid Nabatchi Ahmadi Masoud MokhtaryAn efficient synthesis of chromenylphenylpropanone derivatives as warfarine-like analogues was developed by the Michael addition of 4-hydroxycoumarin to α,β-unsaturated compounds in the presence of polyvinylpolypyrrolidone supported antimony(III) chloride (PV چکیده کاملAn efficient synthesis of chromenylphenylpropanone derivatives as warfarine-like analogues was developed by the Michael addition of 4-hydroxycoumarin to α,β-unsaturated compounds in the presence of polyvinylpolypyrrolidone supported antimony(III) chloride (PVPP-SbCl3) as a new polymeric Lewis acid catalyst in chloroform at reflux conditions without formation of 2,4-diarylpyrano[3,2-c]chromen-5(4H)-ones. The synthesized compounds were identified by FT-IR, 1HNMR and 13CNMR spectroscopic techniques and elemental analysis. Polyvinylpolypyrrolidone supported antimony(III) chloride was characterized via Fourier transform infrared spectroscopy (FT-IR), thermal gravimetric analysis (TGA), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). Clean methodologies, simple preparation of the catalyst, good yields, environmentally friendly and reusable catalyst are some advantages of this work. پرونده مقاله -
دسترسی آزاد مقاله
26 - Preparation, Characterization and Application of a Novel Organic-Inorganic Hybrid Magnetic Nanomaterial as a Highly Efficient Catalyst for the Synthesis of Bis-Coumarins
Marziyeh Barzegar Abdolkarim Zare Aysoda Ghobadpoor Manije DianatA novel organic-inorganic hybrid magnetic nanomaterial, namely nano-[Fe3O4@SiO2@R-NMe2][FeCl4] (nano-[FSRN][FeCl4]) was prepared, and characterized by EDX, elemental mapping, FE-SEM, FT-IR, XRD, VSM, TG and DTG analyses. Then, it was applied as a highly efficient and ma چکیده کاملA novel organic-inorganic hybrid magnetic nanomaterial, namely nano-[Fe3O4@SiO2@R-NMe2][FeCl4] (nano-[FSRN][FeCl4]) was prepared, and characterized by EDX, elemental mapping, FE-SEM, FT-IR, XRD, VSM, TG and DTG analyses. Then, it was applied as a highly efficient and magnetically recyclable catalyst for the solvent-free synthesis of bis-coumarins from 4-hydroxycoumarin (2 eq.) and arylaldehydes (1 eq.). NMe2 is a basic group, and FeCl4− is a Lewis acid; thus, nano-[FSRN][FeCl4] can act as a dual-functional catalyst; based on this and the literature, a plausible mechanism was proposed for the reaction. پرونده مقاله -
دسترسی آزاد مقاله
27 - Nano-[SiO2@R-Im-SO3H][CF3COO]: an effectual catalyst for the production of bis-coumarins and N,N′-alkylidene bisamides
Jaleh Atashrooz Abdolkarim ZareA novel organic-inorganic hybrid nanomaterial namely nano-[SiO2@R-Im-SO3H][CF3COO] (NSRISC) was synthesized, and characterized using FT-IR, EDS, FE-SEM, TGA and XRD analyses. Thereafter, the solvent-free production of bis-coumarins (from aryl aldehydes and 4-hydroxycoum چکیده کاملA novel organic-inorganic hybrid nanomaterial namely nano-[SiO2@R-Im-SO3H][CF3COO] (NSRISC) was synthesized, and characterized using FT-IR, EDS, FE-SEM, TGA and XRD analyses. Thereafter, the solvent-free production of bis-coumarins (from aryl aldehydes and 4-hydroxycoumarin) and N,N′-alkylidene bisamides (from aryl aldehydes and benzamide) was catalyzed by NSRISC. Bis-coumarins were produced in 86-97% at 100 ºC, and bisamides were obtained in 87-97% at 105 ºC. The reaction times were 15-30 min for both kinds of compounds. پرونده مقاله -
دسترسی آزاد مقاله
28 - The use of recyclable magnetic nanocatalyst Fe3O4@SiO2-(CH2)3-Pyridine-2-(1H)-tetrazole-Cu(II) in the synthesis of bis-coumarin derivatives under green conditions
Ali Oji Moghanlou Mohammadali Pourshahi Siamak Atabak Nayer Mohammadian TarighiIn the present work, first, magnetic nanoparticles (MNP) were synthesized, and a layer of silica was placed on the magnetite nanoparticles through the reaction with TEOS. Next, the pyridine-2-(1H)-tetrazole ligand was fixed on the core-shell magnetite nanoparticles, and چکیده کاملIn the present work, first, magnetic nanoparticles (MNP) were synthesized, and a layer of silica was placed on the magnetite nanoparticles through the reaction with TEOS. Next, the pyridine-2-(1H)-tetrazole ligand was fixed on the core-shell magnetite nanoparticles, and finally, the nanocatalyst copper complex was synthesized. The synthesized copper (II) complex of magnetic nanocatalyst was identified through different analyses such as FT-IR, SEM, EDX, XRD, VSM, BET, and atomic absorption. After characterizing the nanocatalyst Fe3O4@SiO2-(CH2)3-Pyridine-2-(1H)-tetrazole-Cu(II), by applying this catalyst in the reaction of benzaldehyde with 4-hydroxycoumarin, the reaction conditions such as solvent type, reaction temperature and The amount of catalyst was optimized. Ethanol was chosen as the optimal solvent as an environmentally friendly solvent. The recycling cycle of the magnetic catalyst was also studied, and the slight decrease in the catalyst's efficiency after six times reactions indicates the high efficiency of this nanocatalyst in the synthesis reaction of bis-coumarin derivatives as a green catalyst. پرونده مقاله -
دسترسی آزاد مقاله
29 - Magnetically recoverable nano-crystalline NiFe2O4 catalyzed green and sustainable synthesis of functionalized pyrano-pyrazol, pyrano-coumarin, and 4H-chromene derivatives
Koyel PradhanSynthesis of pyrano-pyrazol, pyrano-coumarin, and 4H-chromene derivatives has been achieved by the multicomponent reaction of substituted 1,3-diketo compounds, dialkyl acetylene dicarboxylates and alkyl nitrile derivatives in presence of nano-NiFe2O4. The nano-NiFe2O4 m چکیده کاملSynthesis of pyrano-pyrazol, pyrano-coumarin, and 4H-chromene derivatives has been achieved by the multicomponent reaction of substituted 1,3-diketo compounds, dialkyl acetylene dicarboxylates and alkyl nitrile derivatives in presence of nano-NiFe2O4. The nano-NiFe2O4 magnetic nanoparticle was prepared by a simple and effective method and characterized by using XRD, HRTEM images, IR, and VSM studies. The green, convenient, and mild protocol provided large access to desired products in almost quantitative yield. High catalytic activity, very low catalyst loading, and high recyclability are the attractive features of the developed protocol. All reactions were easily performed and preceded with high efficiency under very mild conditions avoiding time-consuming, costly catalysts, and tedious workup and purification of process. پرونده مقاله -
دسترسی آزاد مقاله
30 - Silica gel: A very cheap, reusable, and efficient catalyst for green preparation of some bis-4-hydroxycoumarin on water
Saeed Khodabakhshi Mojtaba BaghernejadSilica gel has been used for synthesis of biscoumarin derivatives starting from 4-hydroxycoumarin and aryl aldehydes. The reaction conditions are completely in agreement with green chemistry principles including sing water as media and a recyclable and safe catalyst. Th چکیده کاملSilica gel has been used for synthesis of biscoumarin derivatives starting from 4-hydroxycoumarin and aryl aldehydes. The reaction conditions are completely in agreement with green chemistry principles including sing water as media and a recyclable and safe catalyst. This method is also simple and inexpensive and leads to high yield of products in short reaction times. پرونده مقاله -
دسترسی آزاد مقاله
31 - Silica-bonded n-propyldiethylenetriamine sulfamic acid as a recyclable solid acid catalyst for the synthesis of coumarin and biscoumarin derivatives
Khodabakhsh Niknam Seyed Ahmad Sajadi Roghayeh Hosseini Mojtaba BaghernejadSilica-bonded n-propyldiethylenetriamine sulfamic acid (SBPDSA) was found as an efficient solid acid for the synthesis of coumarins. Coumarin derivatives were obtained via the Pechmann condensation reaction of phenols and β-keto-esters at 80 oC under solvent-free c چکیده کاملSilica-bonded n-propyldiethylenetriamine sulfamic acid (SBPDSA) was found as an efficient solid acid for the synthesis of coumarins. Coumarin derivatives were obtained via the Pechmann condensation reaction of phenols and β-keto-esters at 80 oC under solvent-free conditions. Also, biscoumarins were obtained via the condensation of aldehydes and 4-hydroxycoumarin in water at reflux conditions. The heterogeneous solid acid showed much the same efficiency when used in consecutive reaction runs. پرونده مقاله -
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32 - Synthesis and in-vitro antimicrobial screening of 3-cinnamoyl coumarin and 3-[3-(1H-indol-2-yl)-3-aryl-propanoyl]-2H-chromen-2-ones
Somnath Gholap Umesh Deshmukh Macchindra TambeAn efficient synthesis of some novel coumarin derivatives via 1, 4- Michael addition of indole to coumarin chalcones catalyzed by cellulose sulphonic acid (CSA) under solvent free conditions is described. The corresponding Michael addition products were obtained in good چکیده کاملAn efficient synthesis of some novel coumarin derivatives via 1, 4- Michael addition of indole to coumarin chalcones catalyzed by cellulose sulphonic acid (CSA) under solvent free conditions is described. The corresponding Michael addition products were obtained in good to excellent yield. The synthesized compounds were screened for their antibacterial activity against E. coli, S. aureus and anti-fungal activity against C. albicans. All the synthesized compounds show moderate to good antimicrobial activity. پرونده مقاله -
دسترسی آزاد مقاله
33 - DFT/NBO Analysis of Interaction between 4-hydroxycoumarin and Single Walled Carbon Nanotubes in Pistachio
Azar BagheriFruits, vegetables, oils, coffee, nuts, and tea contain coumarin. The scientific attraction of coumarins is attributed to their pharmacological activity. In this study, density functional theory (DFT) calculations were performed in the B3LYP/6-31G(d) level of theory to چکیده کاملFruits, vegetables, oils, coffee, nuts, and tea contain coumarin. The scientific attraction of coumarins is attributed to their pharmacological activity. In this study, density functional theory (DFT) calculations were performed in the B3LYP/6-31G(d) level of theory to evaluate the potentialities of single-walled carbon nanotubes (SWCNT) as a carrier for 3-acetyl-6-methyl-4-hydroxy-coumarin. The natural bond orbital (NBO) analysis suggested that the functionalized nanotube plays the role of an electron donor and 3-acetyl-6-methyl -4-hydroxy- coumarin molecule acts as an electron acceptor at the SWCNT -coumarin complex. Variations of density and dipole moment values of coumarin after interaction were studied. Also, the frontier orbital energies, HOMO-LUMO gap, chemical hardness (η), electrophilicity index (ω), charge transferred (ΔNmax) and chemical potential (μ) were computed. Pure coumarin is less conductive and smoother than SWCNT -coumarin. Our results show efficient coumarin loading with the interaction energy of -1.19 eV. NBO analysis shows that the occupied orbitals in the coumarin and the unoccupied orbitals in the nanotube overlap. پرونده مقاله