531-59-9Relevant academic research and scientific papers
Applied photochemistry - Light controlled perfume release
Derrer, Samuel,Flachsmann, Felix,Plessis, Caroline,Stang, Melanie
, p. 665 - 669 (2007)
Ambient light is one of the most suitable available trigger conditions for the release of covalently bound volatile odorants in home- and laundry-care applications. We report on three complementary classes of light-cleavable fragrance precursors, covering the controlled release of odorants with a wide range of functional groups. o-Hydroxy cinnamates 1 undergo a UV-induced double bond isomerization followed by transesterification to release coumarin and a fragrance alcohol of choice. α-Alkoxyacetophenones 10 and α,α-dialkoxyacetophenones 12 undergo Norrish type II fragmentations upon UV-irradiation, thereby releasing one or two equivalents of fragrant aldehydes, respectively. Finally, photoexcited Xanthenoic esters 22 undergo fragmentation to release reactive acyl radicals, which further cyclize onto internal olefins to form perfumery lactones of various ring sizes. Schweizerische Chemische Gesellschaft.
ACCUMULATION OF COUMARINS IN ELICITOR-TREATED CELL SUSPENSION CULTURES OF AMMI MAJUS
Hamerski, Daria,Beier, Ross C.,Kneusel, Richard E.,Matern, Ulrich,Himmelspach, Karl
, p. 1137 - 1142 (1990)
Heterotrophic cell suspension cultures were initiated from hypocotyls of young Ammi majus L. seedlings.When these cultures were propagated continuously in the dark, they produced only traces of the coumarin umbelliferone.Upon addition of fungal cell wall fractions, i.e. a skleroglucan or an elicitor from either Phytophthora megasperma f. sp. glycinea or Alternaria carthami, the cells excreted large amounts of umbelliferone in addition to isopimpinellin, (S)-marmesin, (R)-ammirin, umbelliferone--ether and umbelliferone--ether.The last two compounds are new compounds and appear to be derived from 7-O-prenylumbelliferone, a coumarin that has been identified in from other plants.The Phytophthora-elicitor was the most effective inducer of coumarin accumulation.When cultures which had been elicited for 3 hr were pulsed with L-14C>phenylalanine for 7 hr, all the coumarins and an additional, still unidentified compound in the extracts were labelled efficiently.Our results suggest that A. majus cells are particularly suitable for biosynthetic studies on various coumarins as well as for regulatory studies of the inhibition of coumarin phytoalexin accumulation.
Cu-Catalyzed Phenol O-Methylation with Methylboronic Acid
Bartlett, Mairead E.,Chavez, Angela K.,Gaffney, Uma Bhagwat,Gorin, David J.,Lee, Joyce,Sharew, Betemariam,Wu, Miranda,Zhu, Yingchuan
supporting information, p. 5661 - 5664 (2021/11/11)
A Cu-catalyzed oxidative cross-coupling of phenols with methylboronic acid to form aryl methyl ethers has been developed, expanding the scope of Chan-Evans-Lam alkylation. Electron-deficient phenol derivatives with a broad array of functional groups are methylated in high yields. Increased reaction temperature and catalyst loading enables the methylation of substrates incorporating pyridine and dihydroquinolone motifs. Electron-rich phenol derivatives are poor substrates for the methylation; the characterization of C?H homodimerization products formed from these substrates illuminates a competing mechanistic pathway.
Cycloreversion performance of coumarin and hetero-coumarin dimers under aerobic conditions: Unexpected behavior triggered by UV-A light
Bieniek, Nikolai,Hampp, Norbert,Inacker, Sebastian
, p. 17703 - 17712 (2021/08/30)
Photochemical [2+2]-cycloadditions of coumarin-like monomers are the textbook paradigms of photo-formation and photo-cleavage reactions. The electronic conjugation length of monomers and dimers is quite different which results in almost fully separated UV/Vis absorption bands in the UV-A and UV-C. This feature enables the selective light-controlled conversion between monomeric and dimeric forms by the choice of the appropriate wavelengths. Several applications are based on this kind of reversible photo linker without absorption in the visible range. But which is the best molecule from the coumarin family for such an application? Within this study, we compared the photochemical cleavage behavior of twelve coumarin-type cyclobutane dimers. In particular, the influence of isomer structure and substitution pattern was studied. Two dimers with an unexpected high quantum yield for cyclobutane cleavage were identified. This behavior is explained through the differing ring strain of the cyclobutane moiety. Electron donating substitutions of the framework, e.g. with a methoxy function (+M-effect), leads to a decreased oxidation potential, making the dimers sensitive towards oxidative dimer splitting. This result disqualifies coumarins, e.g. attached to a polymer backbone via an ether bond, often in the 7-position, because of their instabilities and side reactions in an aerobic environment. The methylated dimers (+I-effect) show excellent stability towards this undesired side reaction as well as a high cleavage efficiency upon irradiation with 265 nm. All twelve investigated dimers are ranked for their quantum efficiency and rate constant for cleavage at 265 nm, as well as their oxygen tolerance. As the most promising derivative within our scope for applications the methylated coumarin dimer was identified.
Trialkylammonium salt degradation: Implications for methylation and cross-coupling
Assante, Michele,Baillie, Sharon E.,Juba, Vanessa,Leach, Andrew G.,McKinney, David,Reid, Marc,Washington, Jack B.,Yan, Chunhui
, p. 6949 - 6963 (2021/06/02)
Trialkylammonium (most notably N,N,N-trimethylanilinium) salts are known to display dual reactivity through both the aryl group and the N-methyl groups. These salts have thus been widely applied in cross-coupling, aryl etherification, fluorine radiolabelling, phase-transfer catalysis, supramolecular recognition, polymer design, and (more recently) methylation. However, their application as electrophilic methylating reagents remains somewhat underexplored, and an understanding of their arylation versus methylation reactivities is lacking. This study presents a mechanistic degradation analysis of N,N,N-trimethylanilinium salts and highlights the implications for synthetic applications of this important class of salts. Kinetic degradation studies, in both solid and solution phases, have delivered insights into the physical and chemical parameters affecting anilinium salt stability. 1H NMR kinetic analysis of salt degradation has evidenced thermal degradation to methyl iodide and the parent aniline, consistent with a closed-shell SN2-centred degradative pathway, and methyl iodide being the key reactive species in applied methylation procedures. Furthermore, the effect of halide and non-nucleophilic counterions on salt degradation has been investigated, along with deuterium isotope and solvent effects. New mechanistic insights have enabled the investigation of the use of trimethylanilinium salts in O-methylation and in improved cross-coupling strategies. Finally, detailed computational studies have helped highlight limitations in the current state-of-the-art of solvation modelling of reaction in which the bulk medium undergoes experimentally observable changes over the reaction timecourse. This journal is
Gold(I)-Catalyzed Intramolecular Hydroarylation of Phenol-Derived Propiolates and Certain Related Ethers as a Route to Selectively Functionalized Coumarins and 2 H-Chromenes
Cervi, Aymeric,Vo, Yen,Chai, Christina L. L.,Banwell, Martin G.,Lan, Ping,Willis, Anthony C.
, p. 178 - 198 (2020/12/22)
Methods are reported for the efficient assembly of a series of phenol-derived propiolates, including the parent system 56, and their Au(I)-catalyzed cyclization (intramolecular hydroarylation) to give the corresponding coumarins (e.g., 1). Simple syntheses of natural products such as ayapin (144) and scoparone (145) have been realized by such means, and the first of these subject to single-crystal X-ray analysis. A related process is described for the conversion of propargyl ethers such as 156 into the isomeric 2H-chromene precocene I (159), a naturally occurring inhibitor of juvenile hormone biosynthesis.
Synthesis and biological evaluation of novel coumarin derivatives in rhabdoviral clearance
Chen, Jiong,Hu, Yang,Liu, Lei,Qiu, Tianxiu,Shan, Lipeng
supporting information, (2021/08/10)
Diseases caused by rhabdoviruses have had a huge impact on the productive lives of the entire human population. The main problem is the lack of drugs for the treatment of this family of viruses. Infectious hematopoietic necrosis virus (IHNV), the causative agent of IHN, is a typical rhabdovirus which has caused huge losses to the salmonid industry. Therefore, in this study, IHNV was studied as a model to evaluate the antiviral activity of 35 novel coumarin derivatives. Coumarin A9 was specifically selected for further validation studies upon comparing the half maximum inhibitory concentration (IC50) of four screened candidate derivatives in epithelioma papulosum cyprinid (EPC) cells, as it exhibited an IC50 value of 2.96 μM against IHNV. The data revealed that A9 treatment significantly suppressed the virus-induced cytopathic effect (CPE) in EPC cells. In addition, A9 showed IC50 values of 1.68 and 2.12 μM for two other rhabdoviruses, spring viremia of carp virus and micropterus salmoides rhabdovirus, respectively. Furthermore, our results suggest that A9 exerts antiviral activity, but not by destroying the virus particles and interfering with the adsorption of IHNV. Moreover, we found that A9 had an inhibitory effect on IHNV-induced apoptosis in EPC cells, as reflected by the protection against cell swelling, formation of apoptotic bodies, and loss of cell morphology and nuclear division. There was a 19.05 % reduction in the number of apoptotic cells in the A9 treatment group compared with that in the IHNV group. In addition, enzyme activity assays proved that A9 suppressed the expression of caspase 3, 8 and 9. These results suggested that A9 inhibit viral replication, to some extent, by blocking IHNV-induced apoptosis. In an in vivo study, A9 exhibited an anti-rhabdovirus effect in virus-infected fish by substantially enhancing the survival rate. Consistent with the above results, A9 repressed IHNV gene expression in virus-sensitive tissues (brain, kidney and spleen) in the early stages of virus infection. Importantly, the data showed that horizontal transmission of IHNV was reduced by A9 in a static cohabitation challenge model, especially in fish that underwent bath treatment, suggesting that A9 might be a suitable therapeutic agent for IHNV in aquaculture. Therefore, coumarin derivatives can be developed as antiviral agents against rhabdoviruses.
Concise Synthesis of Chromene/Chromane-Type Aryne Precursors and Their Applications
Xu, Yuan-Ze,Tian, Jia-Wei,Sha, Feng,Li, Qiong,Wu, Xin-Yan
, p. 6765 - 6779 (2021/05/06)
The gram-scale synthesis of 5,6-, 6,7-, and 7,8-chromene/chromane-type aryne precursors and their applications in regioselective transformation to other functional derivatives is reported. Chromene/chromane-type arynes are generated under mild conditions, which can further undergo [2 + 2], [3 + 2], and [4 + 2] cycloaddition reactions, nucleophilic addition reactions, and σ-insertion reactions to produce structurally novel substituted chromenes and chromanes. The excellent regioselectivity of the reaction is facilitated by the oxygen-containing guiding groups at the ortho-position of the triple bond, which can be removed or switched to other functional groups including alkenyl, aryl, heteroaryl, and arylamino groups.
Fe(III)-Catalyzed Decarboxylative C3-Difluoroarylmethylation of Coumarins with α,α-Difluoroarylacetic Acids
Chen, Zhiwei,Bai, Xiang,Sun, Jie,Xu, Yicheng
supporting information, p. 7674 - 7682 (2020/07/15)
A facile Fe(III)-catalyzed oxidative decarboxylative radical coupling reaction of α,α-difluoroarylacetic acids with coumarins has been developed. This transformation, which provides a series of C-3 difluoroarylmethylated coumarins containing various functional groups in moderate-to-good yields, features easily accessible starting materials and operational simplicity.
Design, synthesis and biological evaluation of O-alkyl umbelliferone derivatives as pancreatic lipase inhibitors
Yadav, Nisha,Auti, Prashant,George, Ginson,Paul, Atish T.
, p. 1265 - 1271 (2020/12/04)
A series of coumarin derivatives were synthesised through O-alkylation of umbelliferone. These derivatives were screened for their pancreatic lipase (PL) inhibitory potential. The PL inhibitory effect of compounds with various benzyl and long chain alkyl substituents on umbelliferone were analysed. The compound 1g, having the geranyl substituent was found to have better PL inhibitory potential with an IC50 of 21.64 M. The compounds 1a-j were subjected to molecular docking into the crystal structure of human PL. The molecular docking results are in correlation with the in vitro PL inhibition activity, wherein compound 1g showed a higher MolDock score of -122.12 kcal/mol. The long chain alkyl groups were found to have PL inhibition due to additional interactions with lid domain amino acids (Phe215, Tyr114, Phe77), as revealed by molecular docking study.
