6093-80-7Relevant academic research and scientific papers
Palladium(II)-Catalyzed Intramolecular C-H Alkenylation for the Synthesis of Chromanes
Carral-Menoyo, Asier,Misol, Alexander,Gómez-Redondo, Marcos,Sotomayor, Nuria,Lete, Esther
, p. 2048 - 2060 (2019)
The intramolecular Pd(II)-catalyzed alkenylation of aryl homoallyl ethers constitutes a mild, versatile, and efficient procedure for the synthesis of highly and diversely substituted chromanes and 2H-chromenes. The use of p-TsOH as an additive allows more efficient reactions that could be carried out a room temperature in most cases. The procedure has a wide scope, allowing the synthesis of alkylidenechromanes and 2H-chromenes substituted at C-2 or C-3 of the chromene moiety, thus accessing relevant flavenes and isoflavenes, and even coumarins, in high yields (59 to 91%, 32 examples).
NO2 functionalized coumarin derivatives suppress cancer progression and facilitate apoptotic cell death in KRAS mutant colon cancer
Lin, Mei-Hsiang,Wang, Juo-Shan,Hsieh, Yi-Chen,Zheng, Jia-Huei,Cho, Er-Chieh
, (2019/06/24)
Colon cancer is one of the most lethal cancers worldwide even with the significant progress made in screening techniques and therapeutic agents. Genetic mutations in tumors complicated the treatments, and the survival rate remains low for patients at late or metastatic stages. KRAS gene mutation which leads to failure of the EGFR targeted therapies stands for an example of the challenges in clinical sites. Therefore, development of novel agents for colon cancer treatment is in need. Natural and synthetic coumarin derivatives have been suggested with various biological activities with pharmacologic potential including anti-cancer capacity. Here in this study, five coumarin derivatives, include trifluoromethyl-, dimethoxy-, and/or nitro-substitutions at different positions, were synthesized. Their cancer inhibition potential was investigated in various cancer cell lines. Our data demonstrated that one nitro-coumarin derivate, 5,7-Dimethoxy-4-methyl-6-nitro-chromen-2-one, exhibits cytotoxicity specifically towards colon cancer cells under competitive EC50. Our results showed that this compound can effectively suppress colon cancer cells harboring either wild type or mutant KRAS genes, and that it could inhibit short-term proliferation, long term proliferation, and migration capacities of cancer cells. Finally, we demonstrated that this coumarin derivate facilitates cancer cell death through activation of apoptosis pathway. Our results suggest that this coumarin derivate is a promising lead drug worth further investigation and development for future cancer treatment.
Nucleophilic substitution of hydrogen–the Boger reaction sequence as an approach towards 8-(pyridin-2-yl)coumarins
Fatykhov, Ramil F.,Savchuk, Maria I.,Starnovskaya, Ekaterina S.,Bobkina, Maria V.,Kopchuk, Dmitry S.,Nosova, Emiliya V.,Zyryanov, Grigory V.,Khalymbadzha, Igor A.,Chupakhin, Oleg N.,Charushin, Valery N.,Kartsev, Viktor G.
, p. 299 - 300 (2019/06/13)
5,7-Dimethoxy-8-(3,6-diphenylpyridin-2-yl)coumarins were obtained from 5,7-dimethoxycoumarins and 3,6-diphenyl-1,2,4-triazines via the protocol comprising aromatic SNH substitution in the triazine ring followed by the Boger transform
Palladium-Acid Co-Catalyzed Cleavage of Alkynoates to Construct Dibenzo[c,h]xanthene Derivatives
Tang, Bo-Cheng,Wang, Miao,Ma, Jin-Tian,Wang, Zi-Xuan,Wu, Yan-Dong,Wu, An-Xin
supporting information, p. 4023 - 4028 (2018/09/21)
A novel palladium-acid co-catalyzed C(sp)?C(sp2) cleavage of alkynoates for the construction of dibenzo[c,h]xanthene derivatives is reported. A catalytic amount of triflic acid (TfOH) afforded an efficient transformation into the final product. Furthermore, a reduction process of alkynoates was observed during the formation of dibenzo[c,h]xanthene, preliminary mechanistic studies indicated that the protonation of the new-formed methyl group in dibenzo[c,h]xanthene mainly came from water. (Figure presented.).
α-Glucosidase Inhibition, Antioxidant and Docking Studies of Hydroxycoumarins and their Mono and Bis O-alkylated/acetylated Analogs
Singh, Parvesh,Ngcoya, Nomandla,Mopuri, Ramgopal,Kerru, Nagaraju,Manhas, Neha,Ebenezer, Oluwakemi,Islam, Md. Shahidul
, p. 127 - 135 (2018/03/21)
Background: Diabetes Mellitus (DM) is a complex metabolic disease illustrated by abnormally high levels of plasma glucose or hyperglycaemia. Accordingly, several α-glucosidase inhibitors have been developed for the treatment of diabetes and other degenerative disorders. While, a coumarin ring has the privilege to represent numerous natural and synthetic compounds with a wide spectrum of biological activities e.g. anti-cancer, anti-HIV, anti-viral, anti-malarial, anti-microbial, anti-convulsant, anti-hypertensive properties. Besides this, coumarins have also shown potential to inhibit α-glucosidase leading to a generation of new promising antidiabetic agents. However, the testing of O-substituted coumarins for α-glucosidase inhibition has evaded the attention of medicinal chemists. Methods: For O-alkylation/acetylation reactions, the hydroxyl coumarins (A-B) initially activated by K2 CO3 in dry DMF were reacted with variedly substituted haloalkanes at room temperature under nitrogen. The synthesized compounds were tested for their α-glucosidase (from Saccharomyces cerevisiae) inhibitory activity and anti-oxidant activity using DPPH radical scavenging activity. In silico docking simulations were conducted using CDocker module in DS (Accelrys) to explore the binding modes of the representative compounds in the catalytic site of α-glucosidase. Results: All the coumarin analogues (A1, B1, A2-A10, B2-B8) including their precursors (A-B) were evaluated for their in vitro α-glucosidase inhibition using acarbose as a standard inhibitor. All the mono O-alkylated coumarins (except A1) showed significant (p 50 values ranging between 11.084±0.117 to 145.24± 29.22 μg/mL. Compound 7-(benzyloxy)-4, 5-dimethyl-2H-chromen-2-one (A9) bearing a benzyl group (Ph-CH2 -) at position 7 showed a remarkable (p 50 = 11.084±0.117 μg/mL), almost four-fold more than acarbose (IC50 = 40.578±5.999 μg/mL). The introduction of –NO2 group dramatically improved the anti-oxidant activity of coumarin, while the O-alkylation/acetylation decreased the activity. Conclusion: The present study describes the synthesis of functionalized coumarins and their evaluation for α-glucosidase inhibition and antioxidant activity under in vitro conditions. Based on IC50 data, the mono O-alkylated coumarins were observed to be stronger inhibitors of α-glucosidase with respect to their bis O-alkylated analogues. Coumarin (A9) bearing O-benzyloxy group displayed the strongest α-glucosidase inhibition, even higher than the standard inhibitor acarbose. The coumarin (A10) bearing –NO2 group showed the highest anti-oxidant activity amongst the synthesized compounds, almost comparable to the ascorbic acid. Finally, in silico docking simulations revealed the role of hydrogen bonding and hydrophobic forces in locking the compounds in catalytic site of α-glucosidase.
Rh-Catalyzed Synthesis of Coumarin Derivatives from Phenolic Acetates and Acrylates via C-H Bond Activation
Gadakh, Sunita K.,Dey, Soumen,Sudalai, Arumugam
, p. 11544 - 11550 (2015/12/04)
An efficient annulation strategy involving the reaction of phenolic acetates with acrylates in the presence of [Rh2(OAc)4] as catalyst and formic acid as reducing agent, leading to the high yield synthesis of coumarin derivatives, has been developed. The addition of NaOAc as a base increased the yield of the products. The reaction is quite successful for both electron-rich as well as electron-deficient phenolic acetates, affording coumarins with excellent regioselectivity, and proceeds via C-H bond activation proven by deuterium incorporation studies.
FeCl3-catalysed ultrasonic-assisted, solvent-free synthesis of 4-substituted coumarins. A useful complement to the Pechmann reaction
Prousis, Kyriakos C.,Avlonitis, Nicolaos,Heropoulos, Georgios A.,Calogeropoulou, Theodora
, p. 937 - 942 (2014/02/14)
The catalytic activity of FeCl3 for the synthesis of a variety of 4-substituted coumarins using high energy techniques has been investigated. The ultrasonic-assisted conditions provide a useful complement to the Pechmann reaction, affording the coumarin derivatives in excellent yields, under solvent-free conditions, in short reaction times using an inexpensive, mild and benign Lewis acid catalyst.
Multi-component one-pot synthesis of novel coumarinyldihydropyridines under solvent free conditions
Bohra, Kapil,Sharma, Deepti,Kumar, Banty,Olsen, Carl E.,Parmar, Virinder S.,Prasad, Ashok K.
, p. 1885 - 1891 (2014/01/17)
A library of fourteen 4-coumarinyl-1,4-dihydropyridines (coumarinyl-1,4-DHP) has been synthesized under modified Hantzsch 1,4-dihydropyridine synthesis condition by the condensation of 4-formylcoumarin, alkyl acetoacetate and ammonium acetate in the presence of Ba(NO 3)2 as a catalyst in 58 to 82% yields. Standardization of reaction conditions revealed that 10 mol% of Ba(NO3)2 is enough for optimum yields. The developed methodology does not require the use of organic solvents and hence makes the process eco-friendly. The structure of all the coumarinyl-1,4-DHPs were unambiguously eastablished on the basis of IR, 1H, 13C NMR spectroscopy and HRMS data analysis.
Synthesis of coumarins and neoflavones through zinc chloride catalyzed hydroarylation of acetylenic esters with phenols
Leao, Raquel A. C.,Def.demoraes, Paula,Pedro, Marcella C. B. C.,Costa, Paulo R. R.
experimental part, p. 3692 - 3696 (2011/12/16)
Acetylenic esters react with oxygenated phenols under solvent-free conditions in the presence of only 5 mol% of zinc chloride as a catalyst to give coumarins and neoflavones in reasonable-to-good yields. Georg Thieme Verlag Stuttgart. New York.
Scandium(III) triflate-catalyzed coumarin synthesis
Jung, Keumnyeo,Park, Yun-Jeong,Ryu, Jae-Sang
experimental part, p. 4395 - 4406 (2009/04/11)
Scandium(III) triflate is an excellent catalyst in the von Pechmann condensation. The solvent-free catalytic reactions proceed smoothly with a range of phenols and β-ketoesters in the presence of 10 mol% scandium(III) triflate at 80°C. This simple method affords various 4-substituted coumarins in good to excellent yield and is superior to the classical method in several aspects: solvent-free conditions, short reaction times, a decreased catalyst loading, a mild reaction temperature, and an easy workup. Copyright Taylor & Francis Group, LLC.
