3757-06-0Relevant articles and documents
Encapsulation of functional moieties within branched star polymers: Effect of chain length and solvent on site isolation
Hecht,Vladimirov,Frechet
, p. 18 - 25 (2001)
Porphyrin and pyrene photoactive cores have been encapsulated within an isolating polymeric shell using an efficient and general strategy based on the use of dendritic initiators for the ring-opening polymerization of ε-caprolactone to yield functional core star polymers. The isolation of the core functionalities has been studied using fluorescence quenching and fluorescence resonance energy transfer (FRET) techniques as well as solvatochromic probes. With increasing chain length as well as solvent polarity, enhanced site isolation of the core has been observed. These findings have been correlated to actual molecular dimensions independently measured by pulsed field gradient spin - echo (PGSE) NMR. The developed synthetic methodology offers a rapid route to efficient encapsulation of functional moieties and therefore has potential for the design of new materials.
Blue fluorescence from pyridinyl coumarincarboxymides structure having high quantum yield in solution
Cui, Yanhong,Li, Yujin,Tang, Xue,Xue, Shuai,Yu, Zihua,Zhou, Zichun
, (2022)
Small molecules having fluorescence quantum yields are required to promote biological and organic material applications. In this work, we introduced a series of pyridinyl coumarincarboxymides derivatives, namely 4-XP. These compounds exhibited intense blue fluorescence with high fluorescence quantum yield. By spectral measurement and analysis, it is identified that these pyridine-coumarin conjugates displayed high fluorescence quantum yields (ΦF = 0.77–0.82) blue fluorescence at about 455 nm in nonpolar solvents. Additionally, the solvent effect and fluorescence properties were verified and explained by DFT and TD-DFT calculations.
Photo-controlled growth of polymeric submicron-sized particles
Avó, Jo?o,Lima, Jo?o C.,Parola, A. Jorge
, p. 993 - 996 (2019)
A tripodal coumarin derivative shows complex photoreactivity, changing from intra- to intermolecular photodimerization with increasing concentration. At high concentration, the compound undergoes efficient photopolymerization, resulting in the formation of polymeric submicron-sized particles. The size of these particles can be precisely increased through photoirradiation, without affecting their polydispersity.
Photodecomposition of organic peroxides containing coumarin chromophore: Spectroscopic studies
Polyansky, Dmitry E.,Neckers, Douglas C.
, p. 2793 - 2800 (2005)
The photodecomposition of coumarin-3-t-Bu peroxyester (1) and coumarin-3-carbonyl-m-chlorobenzoylperoxide (2) has been studied using nanosecond and femtosecond spectroscopy to elucidate the nature of transient species involved. Excitation of the coumarin chromophore leads to its singlet excited-state decaying with the rate 9 × 109 s-1 that results from a composite of emission, intersystem crossing, thermal relaxation, and -O-O- bond homolysis. Dissociation of the weak oxygen-oxygen bond proceeds from both triplet and singlet excited states. The nature of this combination of states is predissociative rather than dissociative as demonstrated by the relatively slow rates of oxygen-oxygen bond rupture. The decomposition of 1 and 2 leads to the formation of coumarin-3-carbonyloxyl radical (R1). The later was observed spectroscopically on the nanosecond time scale using both time-resolved FTIR and UV-vis transient techniques. R1 is consumed in two competitive processes: unimolecular decarboxylation and bi-molecular hydrogen atom transfer. The rates of these reactions are 4.3 × 105 s-1 and 1 × 106 M -1 s-1 respectively. The transition state geometries and energies of decarboxylation of R1 have been determined using DFT calculations and are compared with values for the benzoyloxyl radical. The decarboxylation of R1 proceeds via a transition state in which the carboxyl group is almost perpendicular (dihedral angle 114°) to the plane of the coumarin chromophore. The transition state of the benzoyloxyl radical, in contrast, is flat (0°). The varied transition state energies of the radicals (13.6 kcal/mol for coumarin carboxyl radical vs 8 kcal/mol for benzoyloxyl radical) correlate with different decarboxylation rates of these two species.
X-ray crystallographic analysis of N,N-diallylcoumarincarboxamides and the solid-state photochemical reaction
Sakamoto, Masami,Kato, Mamoru,Oda, Eishi,Kobaru, Shuichiro,Mino, Takashi,Fujita, Tsutomu
, p. 3028 - 3032 (2006)
X-ray crystallographic analysis and the photochemical aspects of N,N-diallylcoumarincarboxamides were investigated. Irradiation of the corresponding amides promoted stereoselective intramolecular cyclobutane formation exclusively. The solid-state photoreaction of the coumarinamide without substituent on the 4-position proceeded in a crystal-to-crystal manner. On the other hand, photolysis of the amide possessing a methyl group at the 4-position also effected 2+2 cycloaddition; however, the reaction proceeded much slower. The difference in the reactivity was explainable on the basis of the molecular conformation in the crystal lattice.
Synthesis, biological activity and multiscale molecular modeling studies for coumaryl-carboxamide derivatives as selective carbonic anhydrase IX inhibitors
Zengin Kurt, Belma,Sonmez, Fatih,Durdagi, Serdar,Aksoydan, Busecan,Ekhteiari Salmas, Ramin,Angeli, Andrea,Kucukislamoglu, Mustafa,Supuran, Claudiu T.
, p. 1042 - 1052 (2017)
New coumaryl-carboxamide derivatives with the thiourea moiety as a linker between the alkyl chains and/or the heterocycle nucleus were synthesized and their inhibitory activity against the human carbonic anhydrase (hCA) isoforms hCA I, II, VII and IX were evaluated. While the hCA I, II and VII isoforms were not inhibited by the investigated compounds, the tumour-associated isoform hCA IX was inhibited in the high nanomolar range. 2-Oxo-N-((2-(pyrrolidin-1-yl)ethyl)carbamothioyl)-2H-chromene-3-carboxamide (e11) exhibited a selective inhibitory action against hCA IX with the Ki of 107.9 nM. In order to better understand the inhibitory profiles of studied molecules, multiscale molecular modeling approaches were used. Different molecular docking algorithms were used to investigate binding poses and predicted binding energies of studied compounds at the active sites of the CA I, II, VII and IX isoforms.
Synthesis and antimicrobial activity of coumarin and benzodioxazepine-, diazazepine- and benzoxazepine-substituted penicillins
Bonsignore, L.,Logu, A. de,Loy, G.,Lavagna, S.M.,Secci, D.
, p. 479 - 486 (1994)
Some semisynthetic penicillins 6-substituted with benzo-condensed heterocyclic derivatives were prepared using the reaction of carbon suboxide with Schiff bases and disubstituted benzoic acids.The microbiological assay performed with the penicillins and their intermediates showed a good activity for one Schiff base and a weak activity for the other compounds. coumarin penicillin / Schiff base / carbon suboxide / antimicrobial activity
A novel “turn-off” fluorescent sensor for Al3+ detection based on quinolinecarboxamide-coumarin
Cui, Yanhong,Li, Yujin,Lin, Zhangqi,Niu, Wenjie,Tang, Xue,Zhou, Zichun
, (2020)
Quinolinecarboxamides based on coumarin derivatives were efficiently synthesized and the optical properties were investigated. Compound ZXQ substituted by the diethylamino group on 7-position of coumarin exhibited blue fluorescence (λem ≈ 470 nm) with a high fluorescence quantum yield of 0.92 in Toluene and showed “turn-off” fluorescence property for Al3+. Probe ZXQ formed the 2:1 complex with Al3+ and performed fluorescence quenching in MeCN/H2O (95:5), which exhibited good selectivity and sensitivity. In addition, the mechanism of binding and fluorescence quenching was illustrated by titration experiment, Job’ plot and DFT calculations.
Two benzoyl coumarin amide fluorescence chemosensors for cyanide anions
Wang, Zian,Wu, Qianqian,Li, Jiale,Qiu, Shuang,Cao, Duxia,Xu, Yongxiao,Liu, Zhiqiang,Yu, Xueying,Sun, Yatong
, p. 1 - 6 (2017)
Two new benzoyl coumarin amide derivatives with ortho hydroxyl benzoyl as terminal group have been synthesized. Their photophysical properties and recognition properties for cyanide anions in acetonitrile have also been examined. The influence of electron donating diethylamino group in coumarin ring and hydroxyl in benzoyl group on recognition properties was explored. The results indicate that the compounds can recognize cyanide anions with obvious absorption and fluorescence spectral change and high sensitivity. The import of diethylamine group increases smartly the absorption ability and fluorescence intensity of the compound, which allows the recognition for cyanide anions can be observed by naked eyes. The in situ hydrogen nuclear magnetic resonance spectra combining photophysical properties change and job's plot data confirm that Michael addition between the chemosensors and cyanide anions occurs. Molecular conjugation is interrupted, which leads to fluorescence quenching. At the same time, there is a certain extent hydrogen bond reaction between cyanide and hydroxyl group in the compounds, which is beneficial to the recognition.
New ruthenium(II) complexes functionalized with coumarin derivatives: Synthesis, energy-transfer-based sensing of esterase, cytotoxicity, and imaging studies
Li, Mei-Jin,Wong, Keith Man-Chung,Yi, Changqing,Yam, Vivian Wing-Wah
, p. 8724 - 8730 (2012)
Two new bichromophoric ruthenium(II) complexes, [Ru(bpy) 2(bpy-CM)](PF6)2 and [Ru(bpy) 2(bpy-CM343)](PF6)2 (bpy=2,2'-bipyridine, CM=coumarin) with appended coumarin ligands have been designed and synthesized. The energy-transfer-based sensing of esterase by the complexes has been studied by using UV/Vis and luminescence spectroscopic methods. The cytotoxicity and the cellular uptake of one of the complexes have also been investigated. Woodruff-not only tasty! Two new bichromophoric ruthenium(II) complexes with appended coumarin ligands have been synthesized. The energy-transfer-based sensing of esterase by the complexes was studied by using UV/Vis and luminescence spectroscopy. The RuII complex containing a coumarin 343 derivative was found to exhibit only a slight cytotoxicity towards HepG2 cells, and it was easily taken up in the living cells to show evident response to the esterase (see figure). Copyright
