4361-00-6Relevant academic research and scientific papers
Ionic liquid-mediated synthesis of coumarin-3-carboxylic acids via knoevenagel condensation of Meldrum's acid with ortho-hydroxyaryl aldehydes
Darvatkar, Nitin B.,Deorukhkar, Amol R.,Bhilare, Sachin V.,Raut, Dilip G.,Salunkhe, Manikrao M.
, p. 3508 - 3513 (2008)
A simple, efficient, and green protocol for synthesis of coumarin-3-carboxylic acids is described via Knoevenagel condensation of Meldrum's acid with ortho-hydroxyaryl aldehydes in [Hmim]Tfa ionic liquid, which was found to give better results than other ionic liquids. Furthermore, ionic liquid is easily reused without any appreciable loss in activity. Copyright Taylor & Francis Group, LLC.
Coumarin-3-carboxylic acid derivatives as potentiators and inhibitors of recombinant and native N-methyl-d-aspartate receptors
Irvine, Mark W.,Costa, Blaise M.,Volianskis, Arturas,Fang, Guangyu,Ceolin, Laura,Collingridge, Graham L.,Monaghan, Daniel T.,Jane, David E.
, p. 593 - 600 (2012)
N-Methyl-d-aspartate receptors (NMDARs) are known to be involved in a range of neurological and neurodegenerative disorders and consequently the development of compounds that modulate the function of these receptors has been the subject of intense interest. We have recently reported that 6-bromocoumarin-3-carboxylic acid (UBP608) is a negative allosteric modulator with weak selectivity for GluN2A-containing NMDARs. In the present study, a series of commercially available and newly synthesized coumarin derivatives have been evaluated in a structure-activity relationship (SAR) study as modulators of recombinant NMDAR activity. The main conclusions from this SAR study were that substituents as large as iodo were accommodated at the 6-position and that 6,8-dibromo or 6,8-diiodo substitution of the coumarin ring enhanced the inhibitory activity at NMDARs. These coumarin derivatives are therefore excellent starting points for the development of more potent and GluN2 subunit selective inhibitors, which may have application in the treatment of a range of neurological disorders such as neuropathic pain, epilepsy and depression. Surprisingly, 4-methyl substitution of UBP608 to give UBP714, led to conversion of the inhibitory activity of UBP608 into potentiating activity at recombinant GluN1/GluN2 receptors. UBP714 also enhanced NMDAR mediated field EPSPs in the CA1 region of the hippocampus. UBP714 is therefore a novel template for the development of potent and subunit selective NMDAR potentiators that may have therapeutic applicability in the treatment of patients with cognitive deficits or schizophrenia.
Novel synthetic approach for the access of functionalised 4H-chromenes
Sadeghpour, Mahdieh,Bagheri, Fatemeh
, p. 740 - 743 (2016)
A simple, efficient and high-yielding one-pot protocol for the synthesis of novel functionalised 4H-chromenes and chromene carboxylic acids has been developed using multi-component domino coupling reactions of anil-like compounds with 1,3-diketones and indole in the presence of formic acid catalyst under solvent-free conditions. The protocol avoids the use of expensive catalysts, toxic solvents and chromatographic separation.
A two-photon benzocoumarin-NBD dyad for highly selective and sensitive ratiometric detection of H2S in biological samples
Chen, Guofeng,Gao, Jingshuo,Guo, Zhenbo,Jia, Xu,Li, Xiaoliu,Wei, Chao,Wei, Lingyu,Yang, Shuhan,Zhang, Pingzhu
, (2021)
Hydrogen sulfide (H2S), the third endogenous gas signaling transmitter, plays an important role in the basic signal conduction process of human physiology and pathology. It is critical to monitor the dynamic change of H2S in living organisms. In this article, a two-photon ratiometric fluorescent probe (BCD) based on the benzocoumarin-NBD framework was first designed and synthesized. The probe showed large emission separation (about 115 nm), excellent selectivity, and high sensitivity. Moreover, it could be applied to ratiometric image endogenous H2S biosynthesis in the living cells and zebrafish.
Synthesis and Luminescent Properties of Eu3+ and Tb3+ Complexes with Coumarin-3-carboxylic Acids
Gromak,Kolokolov,Dotsenko,Aksenov,Aksenova
, p. 685 - 692 (2021/06/02)
Abstract: New Eu3+ and Tb3+ complex compounds [Ln(H2O)2L2]Cl?H2O were synthesized on the basis of coumarin-3-carboxylic acid and its derivatives. Composition and structure of the ligands an
Sodium ion chemosensor of 3-oxo-3h-benzo[f]chromene-2- -carboxylic acid: An experimental and computational study
Abror, Ajar Faflul,Al-Anshori, Jamaludin,Hidayat, Ace Tatang,Hidayat, Ika Wiani,Juliandri, Juliandri,Mayanti, Tri,Rahim, Andi,Yusuf, Muhammad
, p. 971 - 982 (2021/10/27)
A fluorescence compound with the typical skeleton of benzocoumarin was synthesized and its interaction with various metal ions was evaluated. The synthesis was performed via Knoevenagel condensation whereas identification of the product was accomplished by various spectroscopic techniques. The chemosensor test against representative metal ions was monitored by fluorescence spectrophotometry. A density functional theory calculation (DFT, functional/basis set; M06/6-31G (d, p)) was also performed to clarify the experimental results and to confirm the mechanism of interaction. 3-Oxo-3H-benzo- [f]chromene-2-carboxylic acid 1 was obtained as a yellow solid in 60 % chemical yield. Melting point; 235.6-236.7 ?C and λmax UV/Vis, λem and Stokes shift (MeOH, nm) of 374, 445 and 71 nm, respectively. The structure of the compound was identified based on spectroscopic data and literature comparison. Compound 1 exhibited a chelation quenched fluorescence (CHQF) phenomenon selectively toward the Na+, with a binding stoichiometry (1:2) and LoD and LoQ of 0.14 and 0.48 mg/L, respectively. Based on DFT calculations, compound 1 chelated Na+ through mechanism of oxidative (1:1 equivalent) and reductive (2:1 equivalent) photoinduced electron transfer (PET), correspondingly.
3-carboxylic acid and formyl-derived coumarins as photoinitiators in photo-oxidation or photo-reduction processes for photopolymerization upon visible light: Photocomposite synthesis and 3d printing applications
Dumur, Frédéric,Gigmes, Didier,Graff, Bernadette,Hamieh, Tayssir,Lalevée, Jacques,Noirbent, Guillaume,Rahal, Mahmoud,Toufaily, Joumana
, (2021/06/16)
In this paper, nine organic compounds based on the coumarin scaffold and different substituents were synthesized and used as high-performance photoinitiators for free radical pho-topolymerization (FRP) of meth(acrylate) functions under visible light irradiation using LED at 405 nm. In fact, these compounds showed a very high initiation capacity and very good polymerization profiles (both high rate of polymerization (Rp) and final conversion (FC)) using two and three-component photoinitiating systems based on coum/iodonium salt (0.1%/1% w/w) and coum/iodonium salt/amine (0.1%/1%/1% w/w/w), respectively. To demonstrate the efficiency of the initiation of photopolymerization, several techniques were used to study the photophysical and photochemical properties of coumarins, such as: UV-visible absorption spectroscopy, steady-state photolysis, real-time FTIR, and cyclic voltammetry. On the other hand, these compounds were also tested in direct laser write experiments (3D printing). The synthesis of photocomposites based on glass fiber or carbon fiber using an LED conveyor at 385 nm (0.7 W/cm2 ) was also examined.
Zirconium(IV) oxychloride: A simple and efficient catalyst for the synthesis of chromen-2-one derivatives
TASQEERUDDIN,ASIRI, YAHYA I.,SHAHEEN
, p. 2611 - 2616 (2020/10/22)
The present work explores a highly efficient, environmental friendly, green protocol for the synthesis of chromen-2-one derivatives (3a-m) by the condensation of salicylaldehydes with various active methylene compounds using zirconium (IV) oxychloride as catalyst. This is a convenient and rapid method for Knoevenagel condensation and this methodology offers several advantages including shorter reaction time, milder conditions, inexpensive catalyst, simple operational procedure and allowed to achieve the desired products in excellent yields. The structures of all the synthesized compounds were confirmed by spectral data.
A Primary Amide-Functionalized Heterogeneous Catalyst for the Synthesis of Coumarin-3-carboxylic Acids via a Tandem Reaction
Khullar, Sadhika,Mandal, Sanjay K.,Markad, Datta
, (2020/08/24)
A crystalline primary amide-based bifunctional heterogeneous catalyst, {[Cd2(2-BPXG)(Fum)2(H2O)2]·2H2O}n (1) (where, 2-BPXG = 2,2′-((1,4-phenylenebis(methylene))bis((pyridin-2-ylmethyl)azanediyl)) diacetamide and Fum = fumarate), has been developed for the one-pot synthesis of a series of potentially biologically active coumarin-3-carboxylic acids at room temperature via a Knoevenagel-intramolecular cyclization tandem reaction. Catalyst 1 is prepared at room temperature from a one-pot self-assembly process in 81% yield and high purity within a few hours and has a ladder-like polymeric architecture based on single-crystal X-ray diffraction. Additional characterization of 1 includes elemental analysis, infrared spectroscopy, thermogravimetric analysis, and powder X-ray diffraction. Based on the optimized conditions, it is determined that 1 is highly efficient (conditions: 2 mol % catalyst, 3 h, and 26-28 °C in methanol) for this reaction. Its recyclability up to five cycles without significant loss of activity and structural integrity is also demonstrated. Using both electron-donating and electron-withdrawing substituents on the salicylaldehyde substrate, seven different derivatives of coumarin-3-carboxylic acid were made. Additionally, the monoamine oxidase (MAO) inhibitor, coumarin-3-phenylcarboxamide, has also been synthesized from coumarin-3-carboxylic acid obtained in the catalysis process. A detailed mechanism of action is also provided.
Synthesis and antioxidant activity of conjugates of hydroxytyrosol and coumarin
Li, Wen-Bo,Qiao, Xue-Peng,Wang, Zi-Xiao,Wang, Shuai,Chen, Shi-Wu
, (2020/11/09)
Antioxidants have been the subject of intense research interest due to their numerous health benefits. In this work, a series of new conjugates of hydroxytyrosol and coumarin were synthesized and evaluated for their free radical scavenging, toxicity and antioxidant mechanism in vitro. The all target compounds 14a–t exhibited better radical scavenging activity than BHT, hydroxytyrosol, and coumarin in both DPPH radical and ABTS+ radical cation scavenging assays. The structure-activity relationships study indicated that the number and position of hydroxyl groups on the coumarin ring were vital to a good antioxidant capacity. Furthermore, the most promising compound 14q showed less toxicity in hemolysis assay and weaker antiproliferative effects than BHT against normal WI-38 and GES cells, and enhanced viability of H2O2-induced HepG2 cells. Additionally, 14q decreased the apoptotic percentage of HepG2 cells, reduced the ROS produce and LDH release, and improved GSH and SOD levels in H2O2-treated HepG2 cells. Lastly, 14q exhibited more stability than hydroxytyrosol in methanol solution. These results revealed that conjugations of hydroxytyrosol and coumarin show better antioxidant capacity, and are the efficacious approach to finding novel potential antioxidant.
