- Tosyl cyanide as a C-sulfinylating agent: 3-sulfinylation of 4-hydroxycoumarins and related heterocycles
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Treatment of 4-hydroxycoumarins and related heterocycles with TsCN under mild basic reaction conditions produces the corresponding 3-sulfinylated products in high yields. Sulfinyl transfer is proposed to occur from sulfinyl cyanate 1, generated in situ by base-catalysed rearrangement of TsCN.
- Akula, Ramulu,Ibrahim, Hasim
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- Rapidly Responsive and Highly Selective Fluorescent Probe for Bisulfite Detection in Food
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The new fluorescent probe 4-hydroxy-3-((2E,4E)-5-phenylpenta-2,4-dienoyl)-2H-chromen-2-one (probe 1) was designed and synthesized for selective detection of sulfite. The fluorescence intensity of the probe was decreased only in the presence of HSO3- all other anions assessed resulted in an increased fluorescence response. Hence, probe 1 acts as a highly selective sensor for HSO3-. This sulfite sensitivity can also be readily monitored visually, as once treated with sulfite the solution shows a marked color change from yellow to colorless. Moreover, probe 1 can be conveniently used as a signal tool to determine the HSO3- levels in various sugar samples.
- Wang, Jialin,Hao, Yanfeng,Wang, Hao,Yang, Shaoxiang,Tian, Hongyu,Sun, Baoguo,Liu, Yongguo
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- Coumarin Derivative Directly Coordinated to Lanthanides Acts as an Excellent Antenna for UV-Vis and Near-IR Emission
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A chelating coumarin-derived ligand sensitizes all emitting lanthanide ions in the solid state and gives high absolute quantum yields for ethanol solutions of complexes of Sm, Eu, Tb, and Dy, above 20% for the last two. Crystal structures of these four complexes are [Ln(Cum)3(H2O)(X)]·X where X = MeOH or EtOH.
- Guzmán-Méndez, óscar,González, Federico,Bernès, Sylvain,Flores-álamo, Marcos,Ordó?ez-Hernández, Javier,García-Ortega, Héctor,Guerrero, Joselin,Qian, Wenjie,Aliaga-Alcalde, Nuria,Gasque, Laura
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- Synthesis, characterization, crystal structure, anti-cancer activities, and computational study of a novel thiophenylchromane
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((thiophen-2-ylmethyl)amino)ethylidene)chromane-2,4-dione (3) was synthesized using 1:1 ratio of 3-acetyl-4-hydroxycoumarin and thiophen-2-ylmethanamine. The main goal of this study was to determine the crystalline structure of compound 3, mainly to investigate if the dominant chemical form is imine or enamine. Therefore, it was synthesized and characterized with FT-IR, 1H NMR, 13C NMR, mass spectroscopy, and elemental analysis. The obtained data were compared with theoretical FT-IR, 1H NMR, 13C NMR calculated with density functional theory (DFT), which confirmed that there is a good correlation between them. The single-crystal X-ray structure of compound 3 was also solved using the crystallography data which confirmed that compound 3 is an enamine rather than an imine. Compound 3 showed significant inhibitory effect against MCF-7, HepG2, U87-MG, SKOV3, MDA-MB231, BEAS-2B, and L929 cell lines (IC50 values 50 values of compound 3 against HepG2 (cancer cell line) and BEAS-2B (normal cell line) were 26.04 and 35.63 μg/mL, respectively.
- Emami, Saeed,Hossaini, Zinatossadat,Shokerzadeh, Mohamad,Vaseghi, Samaneh,Yousefi, Mohamad
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- Proton transfer inhibited charge transfer in a coumarinyl chalcone: Hassle free detection of chloroform vapor in alcohol medium and in neat solution
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The photophysical aspects of a synthesized coumarinyl chalcone derivative 3-((2E, 4E)-5-(4-(dimethylamino) phenyl) penta-2, 4-dienoyl)-4-hydroxy-2H-chromen-2-one (DPPHC) were explored. DPPHC shows excited state intramolecular proton transfer (ESIPT) suppressed excited state intramolecular charge transfer (ESICT) as evidenced from steady state and time resolved spectroscopic analysis. Interestingly, DPPHC behaves as a strong red emitter solely in chloroform and dichloromethane semi-polar solvents exclusively. Using this property, on-spot detection of these two solvents was achieved in paper strips coated with DPPHC as well as in spiked alcohol samples by emission ratiometry change.
- Bhattacharyya, Arghyadeep,Guchhait, Nikhil
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- Synthesis and structures of boron complexes of acyl hydroxy coumarins
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New boron chelates were synthesized by the reactions of 3-acetyl-4-hydroxycoumarin and 8-acyl-7-hydroxy-4-methylcoumarins with boron trifluoride etherate and hydroxybenzodioxaborole. The structure of 3-acetyl-4-difluoroboryloxycoumarin containing an intramolecular C=O...B coordination bond was established by X-ray diffraction.
- Manaev,Chibisova,Lyssenko,Antipin,Traven'
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- Synthesis, photoluminescent behaviors, and theoretical studies of two novel ketocoumarin derivatives
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Two new coumarin derivatives, 3-[3-(4-formylphenyl)prop-2-enoyl]-coumarin (FEC) and 4-hydroxy-3-[3-(4-formylphenyl)prop-2-enoyl]-coumarin (HFEC), were synthesized and characterized by MS, 1H NMR, FT-IR, and TG. The UV-vis absorption and photoluminescence (PL) of FEC and HFEC were also studied. Results show that the two compounds exhibit high fluorescence quantum yields, large Stokes shifts, and strong blue emissions. The molecular structures, the lowest energy transitions, the resonance frequencies, and the UV-vis spectra of FEC and HFEC were calculated using the density functional theory (DFT) and time-dependent density functional theory (TD-DFT) at the B3LYP/6-31G(d) level.
- Li, Jing,Li, Xianggao,Wang, Shirong
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- Synthesis and Spectral Characterization of Asymmetric Azines Containing a Coumarin Moiety: The Discovery of New Antimicrobial and Antioxidant Agents
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Nine unsymmetrical azines containing a coumarin moiety were prepared by the reaction of the hydrazone of 4-hydroxy-3-acetylcoumarin with differently substituted aromatic aldehydes. The azines were fully spectrally characterized, including a complete assignment of 1H- and 13C-NMR resonances, and were assessed for their acute toxicities in the Artemia salina model. Their free radical scavenging activities were tested in the DPPH assay, and in vitro antimicrobial activities were determined against seven bacterial and two fungal strains. The azines containing a p-hydroxyphenyl group were shown to be the most effective antimicrobial agents, and in the case of resistant strains of Staphylococcus aureus and Acinetobacter baumannii, the activity was comparable to that of chloramphenicol. The derivative having a 3,5-dimethoxy-4-hydroxyphenyl group exhibited pronounced antioxidant power reacting rapidly and in 1 : 1 mol ratio with the DPPH radical.
- Risti?, Milenko N.,Radulovi?, Niko S.,Deki?, Biljana R.,Deki?, Vidoslav S.,Risti?, Novica R.,Stojanovi?-Radi?, Zorica
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- Benzopyrans. Part 30. Synthesis of substituted xanthones from 3-acyl-2-methyl-1-benzopyran-4-ones
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The xanthone 8 results from the base catalysed self-condensation of the chromone 1. The chromone 2 gives the xanthones 9 and 11 with sodium and DMF-POCl3 respectively, phenol 14 with NaOMe, and the pyran 22 with 2-thiomethylchromone 6. The enamine 16 on Vilsmeier-Haak reaction affords the chloroxanthone 12. The pyran 15, isolated as a byproduct from the reaction of ω-acetyl-2-hydroxyacetophenone with HC(OEt)3-Ac2O, affords the xanthone 13 by refluxing with NaOMe in MeOH.
- Ghosh, Chandra Kanta,Sahana, Sirin,Patra, Amarendra
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- Synthesis and antiproliferative activity of hybrid thiosemicarbazone derivatives bearing coumarin and d-galactose moieties with EGFR inhibitory activity and molecular docking study
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A series of substituted N-(2,3,4,6-tetra-O-acetyl-β-d-galactopyranosyl)thiosemicarbazones 5a–5j of substituted 3-acetylcoumarins were synthesized with yields of 45–68%. All synthesized thiosemicarbazones were evaluated for cytotoxic activity against several cancer cell lines, such as human breast adenocarcinoma cells MCF7, human liver cancer cells HepG2, human cervical cancer cells HeLa, human melanoma cancer cells SK-Mel-2, and human lung cancer cells LU-1 by using the standard MTT assay. The IC50 values for these cancer cell lines were 1.28–11.81 μM (for MCF-7), 1.53–22.12 μM (for HepG2), 1.43–48.16 μM (for HeLa), 1.82–14.62 μM (for SK-Mel-2), and 1.74–14.62 μM (for LU-1). Most of the compounds were noncytotoxic against human WI-38 normal cell line (IC50 > 16.9 μM). The antiproliferative mechanisms were studied via EGFR inhibition and molecular docking. Docking studies revealed that there are strong interactions between a typical compound with the receptor of the EGFR tyrosine kinase domain with Erlotinib. [Figure not available: see fulltext.]
- Toan, Vu Ngoc,Thanh, Nguyen Dinh
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p. 1868 - 1885
(2021/08/23)
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- Synthesis, computational study and cytotoxicity of 4-hydroxycoumarin-derived imines/enamines
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Abstract: In this study, we applied a direct condensation between 3-acetyl-4-hydroxy-2H-chromen-2-one and different amines (anilines and benzyl amines) in order to synthesize some coumarin-based imines/enamines (3a–o) as cytotoxic agents. All the compounds were characterized by means of FT-IR, NMR, mass spectroscopy and elemental analyses. Since the title compounds can exist as different forms including (s-cis)-imine and (s-trans)-imine or (E and Z)-enamines, their conformational and geometrical aspects were investigated computationally by DFT method. The optimized geometry parameters, ΔE, ΔG, ΔH, Mulliken atomic charge, HOMO and LUMO energy, and NBO analysis suggested that these compounds can exist predominantly in (E)-enamine form. All the synthesized compounds (3a–o) were evaluated in vitro for their cytotoxic activities against cancer cell lines (MCF-7 and A549) and normal cell line (BEAS-2B) using the MTT assay. The 4-hydroxybenzyl derivative 3k was found to be the most potent cytotoxic agent with no selectivity, similar to doxorubicin. However, the 4-chlorobenzyl analog 3o could be considered as an equipotent compound respect to doxorubicin with higher selectivity. Graphic abstract: [Figure not available: see fulltext.].
- Vaseghi, Samaneh,Yousefi, Mohammad,Shokrzadeh, Mohammad,Hossaini, Zinatossadat,Hosseini-khah, Zahra,Emami, Saeed
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p. 1011 - 1024
(2020/05/05)
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- Synthesis and Spectral Characterisation of (E)-3-(3-(4 (Dimethylamino)Phenyl)Acrylo-yl)-4-Hydroxy-2H-Chromen-2-One and Their Antibacterial Activity and Acetylcholinesterase Inhibition
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A new coumarin derivative, (E)-3-(3-(4-(dimethylamino) phenyl) acrylo-yl)-4-hydroxy-2H-chromen-2-one (3), was synthesized by the condensation of 3-acetyl-4-hydroxycoumarin (1) with 4-N,N-dimethylaminobenzaldehyde (2) in the presence of piperidine in ethanol. The structure of the synthesized compound was characterized using spectroscopic data (IR and 1H NMR) and elemental analysis. The antimicrobial properties and acetylcholinesterase inhibition activity (AChEI) of coumarin 3 were investigated, with the highest observed AChEI activity providing 48.25% inhibition. The electronic absorption and emission spectra revealed that 3 exists as two, main keto-enol tautomers. The ratios of these tautomers in both protic and aprotic solvents with different polarities and dielectric constants were calculated. The fluorescence of coumarin 3 was enhanced upon increasing the medium viscosity, which was due to the resultant molecular rigidity. This criterion was further investigated using DNA, whereby 3 showed enhanced fluorescence upon its uptake in DNA grooves and was therefore tested as a novel DNA fluorescent stain.
- Al-Hazmy, Sadeq M.,Alhagri, Ibrahim A.,Ebeid, El-Zeiny M.,Hamdi, Naceur,Okba, Ehab A.,Slimani, Ichraf
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- Angiokinase inhibition of VEGFR-2, PDGFR and FGFR and cell growth inhibition in lung cancer: Design, synthesis, biological evaluation and molecular docking of novel azaheterocyclic coumarin derivatives
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The present work represents the design and synthesis of some azaheterocyclic coumarin derivatives which are evaluated as anti-lung cancer agents. Ten out of the twenty azaheterocyclic compounds showed superior activity than the standard drug staurosporine against non-small cell lung cancer (A549). Representing the four different azaheterocyclic series, compounds 4a, 5d, 6e, and 7d, which demonstrated IC50s of 2.38, 2.39, 1.05 and 3.98 μM, respectively, each exhibiting the best cytotoxicity in its group, were selected for further assessment of their toxicity on normal lung cells (WI-38). Compound 4a was selected for further investigations because it remarkably revealed less cytotoxicity (IC50 = 53.76 μM) than 7d (IC50 = 19.95 μM) on (WI-38) compared to staurosporine (IC50 = 24.41 μM). 4a was assessed for its ability to inhibit the angiokinases VEGFR-2, PDGFR, FGFR and the growth factor EGFR, remarkably it showed better VEGFR-2, PDGFR, FGFR inhibition than the reference drugs used and exhibited as well noticeable EGFR inhibition. Going further, 4a was capable of arresting the cell cycle at pre-G1 phase and S phase and inducing apoptosis. Moreover, the capability of the target 4a to interact with the key amino acids of VEGFR-2 binding site was detected by molecular docking. Finally, the in silico physicochemical properties of 4a were studied.
- Abd Elaziz, Moaaz R.,Abdelrahman, Basel A.,Abdou, Andrew M.,Ahmed, Eman Y.,El-Mansy, Mohamed F.,Elsayed, Kenzi H.,Elserwy, Weam S.,Salem, Abdelrahman M.,Serry, Aya M.
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- Synthesis and Evaluation of 4-Hydroxycoumarin Imines as Inhibitors of Class II Myosins
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Inhibitors of muscle myosin ATPases are needed to treat conditions that could be improved by promoting muscle relaxation. The lead compound for this study ((3-(N-butylethanimidoyl)ethyl)-4-hydroxy-2H-chromen-2-one; BHC) was previously discovered to inhibit skeletal myosin II. BHC and 34 analogues were synthesized to explore structure-activity relationships. The properties of analogues, including solubility, stability, and toxicity, suggest that the BHC scaffold may be useful for developing therapeutics. Inhibition of actin-activated ATPase activity of fast skeletal and cardiac muscle myosin II, inhibition of skeletal muscle contractility ex vivo, and slowing of in vitro actin-sliding velocity were measured. Several analogues with aromatic side arms showed improved potency (half-maximal inhibitory concentration (IC50) 1 μM) and selectivity (≥12-fold) for skeletal myosin versus cardiac myosin compared to BHC. Several analogues blocked neurotransmission, suggesting that they are selective for nonmuscle myosin II over skeletal myosin. Competition and molecular docking studies suggest that BHC and blebbistatin bind to the same site on myosin.
- Brawley, Jhonnathan,Etter, Emily,Heredia, Dante,Intasiri, Amarawan,Nennecker, Kyle,Smith, Joshua,Welcome, Brandon M.,Brizendine, Richard K.,Gould, Thomas W.,Bell, Thomas W.,Cremo, Christine
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p. 11131 - 11148
(2020/11/09)
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- Synthesis and biological evaluation of bis-N2,N2′-(4-hydroxycoumarin-3-yl)ethylidene]-2,3-dihydroxysuccinodihydrazides
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A series of N2,N2′-bis[4-hydroxycoumarin-3-yl)ethylidene]-2,3-dihydroxysuccino-hydrazides, containing 4-hydroxycoumarin, hydrazine and tartaric acid moieties, have been prepared and examined for possible biological activity. Several of these compounds exhibit promising HIV-1 integrase inhibition (IC50 = 3.5 μM), and anti-T. brucei (32% viability) and anti-mycobacterial (Visual MIC90 = 15.63 μM) activity.
- Hoppe, Heinrich C.,Isaacs, Michelle,Kaye, Perry T.,Krause, Rui W. M.,Manyeruke, Meloddy H.,Seldon, Ronnett,Tshiwawa, Thendamudzimu,Warner, Digby F.
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- Design, synthesis, biological and in silico evaluation of coumarin-hydrazone derivatives as tubulin targeted antiproliferative agents
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Coumarin-based different series of hydrazone derivatives were synthesized and evaluated for anticancer activity against four different human cancer cell lines. The activity of the compounds were compared with doxorubicin as a standard drug and all the compounds exhibited good to moderate cytotoxicity with IC50 values ranging from 6.07 to 60.45 μM against all the examined cancer cell lines. Based on the screening results, it was concluded that the compounds 12a and 18a were the most promising medicinal entities. In vitro tubulin polymerisation inhibition assay was performed for the compounds 12a and 18a and these two compounds displayed good potency when compared with colchicine as the standard drug. The interaction of these compounds with tubulin protein was also studied with the help of molecular docking technique using Discovery studio software. Furthermore, the molecular and ADMET properties of the compounds were computed with Osiris property software and PreADMET server. The compounds exhibited exciting in vitro and in silico results. Hence we propose that the compounds 12a and 18a could be developed as tubulin targeted potential antiproliferative agents.
- Govindaiah,Dumala, Naresh,Mattan, Irshad,Grover, Paramjit,Jaya Prakash
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- Synthesis of new 2-amino-6-(4-hydroxy-2-oxo-chromen-3-yl)-4-aryl nicotine nitrile in eco-friendly media and their antimicrobials and DPPH radical scavenging activities
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A simple, green, efficient and economical procedure for the synthesis of, 2-amino-6-(4-hydroxy-2-oxo-chromen-3-yl)-4-(aryl) nicotine nitrile (4a-g) by two routes carried in same conditions, have been reported. The new compounds 4a-g were characterized by 1H NMR, 13C NMR, FT-IR and elemental analysis. The synthesized compounds were screened for their antibacterial activities against Gram-positive bacterial strains (Micrococcus luteus LB14110, Staphylococcus aureus ATCC 6538, Listeria monocytogenes ATCC 19117), Gram-negative bacteria (Escherichia coli, Salmonella typhimurium ATCC 14028 and Pseudomonas aeruginosa). The coumarin derivative 4a and 3-acetyl-4-hydroxycouamrin (1) were the most active against two bacteria Staphylococcus aureus ATCC 6538 and Candida albicans respectively. The best minimum inhibitory concentration values were obtained for the compound 4a against Candida albicans (0.0195 g/cm3). In addition, compounds 4a-g were investigated for their antioxidant activities by DPPH (2,2-diphenyl-1-picrylhydrazyl) in which most of them displayed significant antioxidant activities.
- Mnasri, Aziza,Chakchouk-Mtibaa,Al-Ayed, Abdullah Sulaiman,Jemmali, Mosbah,Mellouli,Bilel, Hallouma,Hamdi, Naceur
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p. 1609 - 1616
(2019/06/11)
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- Studying the cytotoxicity of coumarin–chalcone hybrids by a prooxidant strategy in A549 cells
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Abstract: Curcumin, bearing two electrophilic α,β-unsaturated ketones, is a promising anticancer agent by an electrophilicity-based prooxidant strategy (ROS-generating) due to the Michael acceptors. Considering that ROS generation depends on Michael acceptor unit, we have designed and synthesized two series coumarin–chalcone hybrids containing one or two Michael acceptor units through Claisen–Schmidt condensation, and evaluated the cytotoxicity against A549 cells as well as ROS accumulation. (E)-3-[3-(2-Hydroxyphenyl)acryloyl]-2H-chromen-2-one was identified as the strongest ROS inducer and cytotoxic agent. The structure–activity relationships (SAR) indicated that the Michael acceptor unit was more important than the position of hydroxyl to the cytotoxicity mediated by increasing the cellular lever of ROS. In addition, (E)-3-[3-(2-hydroxyphenyl)acryloyl]-2H-chromen-2-one caused S-phase cell cycle arrest in A549 cells. Therefore, this work provides an example of coumarin–chalcone scaffold as cytotoxic agent by a prooxidant (ROS-generating agent) strategy. Graphical abstract: [Figure not available: see fulltext.].
- Shang, Ya-jing,Wei, Qiang,Sun, Zhi-bin
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p. 2287 - 2292
(2018/10/31)
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- A coumarin-chalcone hybrid used as a selective and sensitive colorimetric and turn-on fluorometric sensor for Cd2+ detection
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A chalcone-based naked-eye colorimetric chemical sensor, (E)-4-hydroxy-3-(3-(4-methoxyphenyl)acryloyl)-2H-chromen-2-one 1a, was developed for selective and sensitive recognition of Cd2+ in mixed aqueous-organic media. The chemosensor demonstrates a distinct color change as well as a remarkable variation in the absorption and fluorescence enhancement observed in its emission spectra upon interaction with Cd2+. The dual colorimetric and fluorometric responses of the chemosensor 1a towards Cd2+ are attributed to the formation of a 1 : 1, 1a-Cd2+ complex, which eventually affect its optical properties. The association constants for Cd2+ towards receptor 1a obtained from the Benesi-Hildebrand plot and non-linear least square fitting were found to be 9.56 × 105 M-1 and 1.34 (±0.87) × 106 M-1, respectively, with a detection limit of 5.84 × 10-8 M. The fluorescence enhancement of chemosensor 1a upon interaction with Cd2+ was attributed to chelation-enhanced fluorescence (CHEF) occurring at pH 7.0.
- Shaily,Kumar, Ajay,Ahmed, Naseem
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p. 14746 - 14753
(2017/11/28)
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- Affinity-based small fluorescent probe for NAD(P)H:quinone oxidoreductase 1 (NQO1). Design, synthesis and pharmacological evaluation
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NQO1 is a dimeric flavoprotein which intimately associated with cancer and overexpressed in the cytosol of numerous human tumor cells. Given that the cellular environment is quite dynamic and versatile, further investigation of the function of NQO1 depends on tools for specific detection of it. Currently, several activity-based assays have been developed to detect NQO1-expressing cancerous tissues. Herein, we report the development of a functional affinity-based small-molecule probe which is composed of a potent small-molecule NQO1 inhibitor 3d as the recognition group, a linker and the fluorophores group FITC. The probe exhibits good inhibitory activity of NQO1 and has been successfully used to label the protein in A549 cells at the micromolar level. These features make the probe favorable for mechanistic studies and cancer diagnostic biomarker. Based on these preliminary results, our laboratory will focus on the further development of fluorescent probe for NQO1, which could be anticipated to be applied in physiological and pathological studies of NQO1.
- Bian, Jinlei,Li, Xiang,Xu, Lili,Wang, Nan,Qian, Xue,You, Qidong,Zhang, Xiaojin
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p. 828 - 839
(2017/02/10)
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- New Coumarin Derivatives as Anti-Breast and Anti-Cervical Cancer Agents Targeting VEGFR-2 and p38α MAPK
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Breast and cervical cancers are the most common gender-specific cancers affecting women worldwide. In this investigation, we highlighted the synthesis, VEGFR-2 and p38α MAPK inhibitory activity of new series of fluorinated coumarin-based derivatives featuring a variety of bioactive chemical moieties attached or fused to the coumarin nucleus at the 3 and/or 4 position. The bioactive inhibitors were further assessed for their anti-proliferative effect against human MCF-7 breast cancer and HeLa cervical cancer cell lines, respectively. Most of the tested compounds showed potent preferential inhibition effects against human VEGFR-2 and remarkable anticancer activities in the human breast cancer cell line MCF-7. Compounds 29, 24, and 2 displayed the highest inhibitory activity against VEGFR-2 (94% inhibition) and they were the most potent anticancer agents toward MCF-7 cancer cells with IC50 values of 7.90, 8.28, and 8.30 μg/mL, respectively. Compound 13 inhibited p38α MAPK phosphorylation with a significant reduction in % cell viability against HeLa cancer cells at 10 and 30 μM. Docking experiments carried out on VEGFR-2 and p38 MAPK crystallographic structures revealed that the active compounds bind to the active sites through H-bonds, arene–cation, and hydrophobic π–π interactions. QSAR analysis demonstrated considerable correlation coefficient (R2 = 0.76969) and root mean square error (RMSE = 0.10446) values. Also, the residual values between the experimental pIC50 and predicted pIC50 are very close, indicating the reliability of the established QSAR model.
- Batran, Rasha Z.,Dawood, Dina H.,El-Seginy, Samia A.,Ali, Mamdouh M.,Maher, Timothy J.,Gugnani, Kuljeet S.,Rondon-Ortiz, Alejandro N.
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- 3-Substituted-4-hydroxycoumarin as a new scaffold with potent CDK inhibition and promising anticancer effect: Synthesis, molecular modeling and QSAR studies
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A new series of 3-substituted-4-hydroxycoumarin derivatives was designed, synthesized, and evaluated for CDK inhibiting and anticancer activities. All the synthesized target compounds showed remarkably high affinity and selectivity towards CDK1B, compared to flavopiridol, with Ki values in the low nanomolar range (Ki?=?0.35–0.88?nM). Most of them elicited considerable inhibiting effect against CDK9T1 (Ki?=?3.26–23.45?nM). Moreover, all the target compounds were tested in vitro against eighteen types of human tumor cell lines. The hydrazone 3a, N-phenylpyrazoline derivative 6b and 2-aminopyridyl-3-carbonitrile derivative 8c were the most potent anticancer agents against MCF-7 breast cancer cell line (IC50?=?0.21, 0.21 and 0.23?nM, respectively). The target compounds 3a, 6b and 8c were further evaluated in MCF-7 breast cancer mouse xenograft model and showed in vivo efficacy at 10?mg/kg dose. The docking study confirmed a unique binding mode in the active site of CDK1B with better score than flavopiridol. Quantitative structure activity relationship study was done and revealed a highly predictive power R2 of 0.81.
- Abdel Latif, Nehad A.,Batran, Rasha Z.,Khedr, Mohammed A.,Abdalla, Mohamed M.
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p. 116 - 129
(2016/07/11)
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- Antileishmanial activity of novel indolyl-coumarin hybrids: Design, synthesis, biological evaluation, molecular docking study and in silico ADME prediction
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In present work we have designed and synthesized total twelve novel 3-(3-(1H-indol-3-yl)-3-phenylpropanoyl)-4-hydroxy-2H-chromen-2-one derivatives 13(a-l) using Ho3+doped CoFe2O4nanoparticles as catalyst and evaluated for their potential antileishmanial and antioxidant activities. The compounds 13a, 13d and 13h were found to possess significant antileishmanial activity (IC50value = 95.50, 95.00 and 99.00 μg/mL, respectively) when compared to the standard sodium stibogluconate (IC50= 490.00 μg/mL). The compounds 13a (IC50= 12.40 μg/mL), 13d (IC50= 13.49 μg/mL), 13g (IC50= 13.24 μg/mL) and 13l (IC50= 13.74 μg/mL) had shown good antioxidant activity when compared with standards butylated hydroxy toluene (IC50= 16.5 μg/mL) and ascorbic acid (IC50= 12.8 μg/mL). After performing molecular docking studies, it was found that compounds 13a and 13d had potential to inhibit pteridine reductase 1 enzyme. In silico ADME pharmacokinetic parameters had shown promising results and none of the synthesized compounds had violated Lipinski's rule of five. Thus, suggesting that compounds from the present series can serve as important gateway for the design and development of new antileishmanial as well as antioxidant agent.
- Sangshetti, Jaiprakash N.,Kalam Khan, Firoz A.,Kulkarni, Abhishek A.,Patil, Rajendra H.,Pachpinde, Amol M.,Lohar, Kishan S.,Shinde, Devanand B.
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p. 829 - 835
(2016/05/24)
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- Synthesis of 2-acylated and sulfonated 4-hydroxycoumarins: In vitro urease inhibition and molecular docking studies
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Sixteen 4-hydroxycoumarin derivatives were synthesized, characterized through EI-MS and 1H NMR and screened for urease inhibitory potential. Three compounds exhibited better urease inhibition than the standard inhibitor thiourea (IC50 = 21 ± 0.11 μM) while other four compounds exhibited good to moderate inhibition with IC50 values between 29.45 ± 1.1 μM and 69.53 ± 0.9 μM. Structure activity relationship was established on the basis of molecular docking studies, which helped to predict the binding interactions of the most active compounds.
- Rashid, Umer,Rahim, Fazal,Taha, Muhammad,Arshad, Muhammad,Ullah, Hayat,Mahmood, Tariq,Ali, Muhammad
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p. 111 - 116
(2016/05/09)
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- Pyrazole based solid state emissive NLOphores with TICT characteristics: Synthesis, DFT and TDDFT studies
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A series of pyrazole based D-π-A derivatives with large stokes shift have been synthesized from 1,3-dipheny-1H-pyrazole-3-carbaldehyde by reacting with a series of active methylenes and characterized by spectroscopic analysis. The synthesized dyes show blue to red solid state emissions in the range of 441-604 nm. All the pyrazole dyes, except dye 2.3.6.4-((1,3-dipheny-1H-pyrazole-4-yl)methylene)-3-methyl-1-phenyl-1H-pyrazol-5(4H)-one, display solid state emission characteristics. Experimental absorption and emission wavelengths measured for all the synthesized dyes are in good agreement with those predicted using the Time-Dependent Density Functional Theory. In this paper, the static first, second hyperpolarizability and its related properties estimated for pyrazole based "push-pull" dyes using B3LYP functional with 6-311G(d) basis sets. We have performed experimental calculation to determine the first hyperpolarizability using solvatochromic shift method. These dyes show high first hyperpolarizability in the range of 39.96-296.35 × 10-30 esu by theoretical method and 35.8-302 × 10-30 esu by solvatochromic shift method.
- Lanke, Sandip K.,Sekar, Nagaiyan
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- Synthesis of some new carbonitriles and pyrazole coumarin derivatives with potent antitumor and antimicrobial activities
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3-Acetyl-4-hydroxycoumarin (2) was reacted with some aldehydes (4-chlorobenzaldehyde, 4-bromobenzaldehyde, 5-methylfurfural) to afford the chalcones (3a-c). Cyclization of these chalcones with malononitrile in the presence of ammonium acetate afforded pyridine carbonitriles (4a-c), while the cyclization reaction of chalcones (3a-c) with ethyl cyanoacetate afforded the oxopyridine carbonitriles (5a-c). On the other hand, the chalcones (3a-c) reacted with hydrazine hydrate in alcohol to yield pyrazoles (6a-c), but when the same reaction is carried out in the presence of acetic acid, the acetyl pyrazole derivatives (7a-c) were obtained. Finally, the reaction of the chalcones (3a-c) with phenylhydrazine afforded phenylpyrazole derivatives (8a-c). The structures of synthesized compounds were confirmed by their micro analysis and spectral data (IR, NMR and MS). Twelve samples were evaluated for the human breast adenocarcinoma cytotoxicity, three of them showed moderate activity, the rest of the samples showed weak cytotoxic activity (very high IC50), but for the hepatocarcinoma cell lines four samples showed weak cytotoxic effect, while the rest of the compounds showed very weak effect. For antimicrobial study, three compounds proved to be the most promising against tested bacterial organisms.
- Abdel Hafez, Omiama M.,Nassar, Mahmoud I.,El-Kousy, Salah M.,Abdel-Razik, Ayman F.,Atalla, Sherien M. M.,El-Ghonemy, Mai M.
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p. 593 - 601
(2014/08/05)
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- A new and efficient method for the synthesis of novel 3-Acetyl coumarins oxadiazoles derivatives with expected biological activity
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This paper presents the design of some novel 3-Acetylcoumarin derivatives, based on minimal inhibitory concentration values (MICs) previously obtained against some microorganism cultures, Gram positive and negative bacteria and fungi. Some of these molecules exhibited antibacterial activity against S. aureus, comparable to that of the standard used (impinem). The in vitro antioxidant activities of the novel 3-Acetylcoumarin oxadiazoles were assayed by the quantitative 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity method. The compounds 5c,d proved to be the most active, showing the highest capacity to deplete the DPPH radicals. Structure elucidation of the products has been accomplished on the basis of IR, 1H-NMR, 13C-NMR, NOESY and HMBC NMR data.
- Al-Ayed, Abdullah Sulaiman,Hamdi, Naceur
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p. 911 - 924
(2014/02/14)
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- Chalcone-based derivatives as new scaffolds for hA3 adenosine receptor antagonists
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Objectives With the aim of finding new adenosine receptor (AR) ligands based on the chalcone scaffold, we report the synthesis of a new series of coumarin-chalcone hybrids and the pharmacological characterization of their actions at four subtypes of AR. Methods The synthesized compounds 5-10 were characterized in radioligand binding (A1, A2A and A 3) and adenylyl cyclase activity assays (A2B) to determine the affinity of the compounds for the four human AR (hAR) subtypes. Key findings Coumarin-chalcone hybrids were found to be ligands with a novel structure, not reported thus far, that showed varying affinity and selectivity for AR subtypes. Conclusions The coumarin-chalcone hybrids in which ring B of the chalcone scaffold was a thiophene (compounds 5 and 9) were found to be the most potent compounds of the series. Compound 9, in which ring A of the chalcone moiety was the phenyl ring of the coumarin, showed similar activity against hA1, hA2A and hA3 ARs, while compound 5, in which ring A of the chalcone was substituted by the benzopyrone ring of the coumarin moiety, showed similar activity only at the hA3 AR and, therefore, was deemed to be selective (Ki (dissociation constant) = 5160 nm). A new series of chalcone-based derivatives, including a coumarin moiety in their structures, have been synthesized and binding assays for the hA1, hA2A, and hA3 adenosine receptors were employed to assess the affinity for receptor subtypes. Isosterical substitutions of one or both phenyl rings of the chalcone moiety reveal that thiophene-containing compounds 5 and 9 have good binding affinity for ARs. Compound 5, in which both phenyl rings of the original chalcone scaffold (rings A and B) were substituted for a thiophene and pyrone rings, resulted selective for the hA3 adenosine receptor (Ki = 5,160 nM). Based on the obtained results, a preliminary structure-activity relationship (SAR) study showed a high selectivity and good potency of these thiophene-containing compounds. 2013 The Authors. JPP
- Vazquez-Rodriguez, Saleta,Matos, Maria Joao,Santana, Lourdes,Uriarte, Eugenio,Borges, Fernanda,Kachler, Sonja,Klotz, Karl-Norbert
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p. 697 - 703
(2013/06/05)
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- Synthesis and photooxygenation of furo[3,2-c]coumarin derivatives as antibacterial and DNA intercalating agent
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Syntheses of 2,3-dimethyl-4H-furo[3,2-c]coumarin and 3-phenyl-4H-furo[3,2- c]coumarin as angular furocoumarins were carried out through Williamson reaction of 4-hydroxycoumarin with α-haloketones followed by cyclization. Photooxygenation of the synthesized furocoumarin derivatives was performed and the photoproducts were isolated and characterized. The affinity of 2,3-dimethyl-4H-furo[3,2-c]coumarin towards DNA and the antibacterial activity were evaluated and compared with 8-methoxypsoralen (8-MOP). Syntheses of 2,3-dimethyl-4H-furo[3,2-c]coumarin and 3-phenyl-4H-furo[3,2-c]coumarin as angular furocoumarins were carried out through Williamson reaction of 4-hydroxycoumarin with α-haloketones followed by cyclization. Photooxygenation of the synthesized furocoumarin derivatives was performed and the photoproducts were isolated and characterized. The affinity of 2,3-dimethyl-4H-furo[3,2-c]coumarin towards DNA and the antibacterial activity were evaluated and compared with 8-methoxypsoralen (8-MOP). Copyright
- Al-Sehemi, Abdullah G.,El-Gogary, Sameh R.
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p. 316 - 320
(2012/04/23)
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- Design, synthesis and biological evaluation of some novel 3-cinnamoyl-4-hydroxy-2H-chromen-2-ones as antimalarial agents
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A novel series of 3-cinnamoyl-4-hydroxy-2Hchromen-2-ones were designed, synthesized and screened for antiplasmodial activity. Eleven compounds of the series exhibited micromolar potency against chloroquine sensitive and chloroquine resistant strains. The most potent compound 4-hydroxy-3-(3-(4- nitrophenyl)acryloyl)-2Hchromen-2-one showed inhibitory potency (IC 50) of 3.1 and 4 μg/ml against chloroquine sensitive and chloroquine resistant strains, respectively. A structure activity relationship study was performed by correlating the effect of substituents with the antimalarial activity of the title compounds. The novel 3-cinnamoyl-4-hydroxy- 2H-chromen-2-ones reported here should be good lead for further development of antimalarial agents that can overcome resistance.
- Patel, Kuldeep,Karthikeyan, Chandrabose,Hari Narayana Moorthy, N. S.,Deora, Girdhar Singh,Trivedi, Piyush,Solomon, Viswas Raja,Lee, Hoyun
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p. 1780 - 1784,5
(2020/07/30)
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- A rapid access to new coumarinyl chalcone and substituted chromeno[4,3-c]pyrazol-4(1H)-ones and their antibacterial and DPPH radical scavenging activities
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A series of new coumarin derivatives 4 containing a chalcone moiety were synthesized by condensation of 3-acetyl-4-hydroxycoumarin 1 with aryl or heteroaryl aldehydes 2 in the presence of piperidine in chloroform. The interaction of 3-formyl-4-chloro-coumarin 3 with nitrogen compound nucleophiles are described and lead to the corresponding substituted chromen[4,3-c] pyrazol-4-ones 5. The structures of the obtained compounds were established on the basis of IR|1D|2D NMR, while crystal structure of 3-acetyl-4-hydroxy coumarin 1 was determined using X-ray diffraction and further were evaluated for possible antibacterial and antioxidant activities. The coumarinic chalcone 4d has been found to be the most active (IC50 = 2.07 μM) in this study.
- Hamdi, Naceur,Fischmeister, Cedric,Puerta, M. Carmen,Valerga, Pedro
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experimental part
p. 522 - 530
(2012/05/04)
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- Synthesis of new substituted chromen[4,3-c]pyrazol-4-ones and their antioxidant activities
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A series of new coumarin derivatives 4 containing a 4-arylbut-3-en-2-one moiety were synthesized by condensation of 3-acetylcoumarin 1 with aryl aldehydes 2 in chloroform in the presence of piperidine. The interactions of 3-formyl-4-chlorocoumarin (3) with nitrogen-containg nucleophiles leading to the corresponding substituted chromen-[4,3- c]pyrazol-4-ones 5 are described. The structures of the obtained compounds were established on the basis of 1D NMR, 2D NMR and IR and further the compounds were evaluated for possible antioxidant activities. The coumarinic chalcone 4a has been found to be the most active (IC50 = 2.07 μM) in this study.
- Al-Ayed, Abdullah Sulaiman
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scheme or table
p. 10292 - 10302
(2012/02/14)
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- Synthesis of some coumarinyl chalcones and their antiproliferative activity against breast cancer cell lines
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A series of coumarinyl chalcones derivatives were synthesized and evaluated for their antiproliferative activities on three different breast cancer cell lines (MDA-MB231, MDA-MB468, MCF7) and one non-cancer breast epithelial cell line (184B5). The coumarinyl derivatives exhibited anticancer activity against breast cancer cell lines at a micromolar range. A structure-activity relationship (SAR) analysis was performed by studying the effect of substituents on their antiproliferative activities. One of the compound 3i bearing methoxy substitutions at the R1; R2 and R3 positions of the phenyl ring showed comparable potency to the reference drug cisplatin as well as a two-fold higher selectivity for the breast cancer cell lines than 184B5 cells.
- Patel, Kuldeep,Karthikeyan, Chandrabose,Solomon, Viswas Raja,Moorthy, N.S. Hari Narayana,Lee, Hoyun,Sahu, Kapendra,Deora, Girdhar Singh,Trivedi, Piyush
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scheme or table
p. 308 - 311
(2012/05/05)
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- Expedious synthesis for α, β-unsaturated coumarin derivatives using boran chelates: A novel class of potential antibacterial and antioxidant agents
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A new family of coumarin derivatives (4a-i) containing a chalcone moiety was synthesized by condensation of 3-acetyl-4-difluoro boryloxycoumarin (2) with aryl and heteroaryl aldehydes with piperidine in chloroform. Resulting compounds were characterized by IR, 13C, 1H NMR and UV visible spectroscopy. Compound 3-((2E)-3-(3,4,5-Trimethoxy-phenyl)prop-2-enoyl)- 2(H)-chromen-2-one (4g) was characterized by single crystal X-ray diffraction. The antioxidant and antibacterial activities of the obtained compounds 4a-i was evaluated. The biological activity found for these compounds is discussed against their structural features, physical and chemical properties.
- Hamdi, Naceur,Bouabdallah, Feten,Romerosa, Antonio,Benhassen, Rached
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experimental part
p. 1261 - 1268
(2011/11/29)
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- Synthesis, anticoagulant and PIVKA-II induced by new 4-hydroxycoumarin derivatives
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The action of the coumarin-type drugs and related compounds is reviewed to their VKOR antagonistic effects. In our study, twenty 3-pyridinyl, pyrimidinyl and pyrazolyl-4-hydroxycoumarin derivatives were synthesized. A comparative in vivo (CT, PT determination) and in vitro (measurement of PIVKA-II levels) anticoagulant study with respect to warfarin showed that the synthesized compounds have different anticoagulant activities, the most prospective compounds were the 3-pyrazolyl-4-hydroxycoumarin derivatives.
- Abdelhafez, Omaima M.,Amin, Kamelia M.,Batran, Rasha Z.,Maher, Timothy J.,Nada, Somaia A.,Sethumadhavan, Shalini
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scheme or table
p. 3371 - 3378
(2010/10/20)
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- Synthesis and antimicrobial screening of 4H-2-berrcoyl-3-hydroxy-3-methyl- 2-phenyl 2,3-dihydro-furo[3,2-c]benzopyran-4-one and 4H-3-methyl-2-phenyl furo[3,2-c]benzopyran-4-one
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3-AcetyI-4-hydroxy-2H[l]benzopyran-2-one 2a-d has been treated with bromodeoxybenzoin in NaOH, THF:HMPA to give 4H-2-benzoyl-3-hydroxy-3-methyl-2- phenyl 2,3-dihydro-furo[3,2-c] benzopyran-4-one 3a-d. This on treatment with aqueous HCI in presence of dioxane gives 4H-3-methyl-2-phenyl furo[3,2-c] benzopyran-4-one 4a-d through acid catalysed 1,2- elimination. All compounds'have been screened for antimicrobial activity. They do not show significant activity.
- Mulwad,Hegde
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scheme or table
p. 128 - 133
(2009/12/04)
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- Synthesis, spectroscopic and antibacterial investigations of new hydroxy ethers and heterocyclic coumarin derivatives
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(Chemical Equation Presented) The reactions between oligoethylene glycol diglycidyl ethers 2a-c with both 7-hydroxy-4-methyl-2H-chromen-2-one and 4-hydroxy-2H-chromen-2-one lead to new hydroxy ethers 3 and 4 containing coumarin moieties to good yield. The
- Hamdi, Naceur,Saoud, Mustapha,Romerosa, Antonio,Hassen, Rached Ben
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experimental part
p. 1835 - 1842
(2009/06/08)
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- Synthesis of novel triketone-based acidichromic colorants
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This letter presents the synthesis and evaluation of two novel triketone-containing acidichromic colorants. Analysis results indicate that both prepared triketone-containing compounds undergo two distinct and reversible color changes under both strongly acidic and basic conditions. Thus, a pH sensitive triketone functional group is introduced for the first time to design and synthesize acidichromic colorants.
- Lin, Ching-Tsan,Shih, Jen-Hao,Chen, Chung-Ling,Yang, Ding-Yah
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p. 5033 - 5037
(2007/10/03)
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- HIGH-PERFORMANCE OPTICAL STORAGE MEDIA
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The invention relates to an optical recording medium comprising a substrate, a reflecting layer and a recording layer, wherein the recording layer comprises a compound of formula (I), or a mesomeric or tautomeric form thereof, wherein Zn+ is a proton or an n-valent ammonium, phosphonium, metal complex or alkali metal cation and n is a number (1), (2) or (3); it being possible, where appropriate, for Zn+ to be linked to R1, R2, R3 or R4 by a direct bond or by way of an O, S or NR8 bridge. R1, to R7 are hydrogen or hydrocarbon radicals defined in the description and claims; R2 and R6 can additionally be halogen or nitro. Novel compounds of formula (I) are also claimed, these being compounds in which Zn+ is a phosphonium, metal complex or alkali metal cation or which are asymmetrical.
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Page/Page column 29-30
(2010/02/14)
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- Novel short-step synthesis of functionalized γ-phenyl-β- hydroxybutenoates and their cyclization to 4-hydroxycoumarins via the N-hydroxybenzotriazole methodology
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A novel method for the synthesis of functionalized 3-substituted 4-hydroxycoumarins is reported. C-Acylation compounds were derived from the reaction of the N-hydroxybenzotriazole ester of the functionalized acetyl salicylic acids and a variety of active methylene compounds and cyclized to the title compounds. The synthesis is simple and the compounds are produced in yields varying from 39 to 80%. The structure of the newly prepared C-acylation compounds was thoroughly studied through NMR spectroscopy for the first time in the literature.
- Athanasellis, Giorgos,Melagraki, Georgia,Chatzidakis, Haralambos,Afantitis, Antreas,Detsi, Anastasia,Igglessi-Markopoulou, Olga,Markopoulos, John
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p. 1775 - 1782
(2007/10/03)
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- Hantzsch reaction of 3-(2-bromoacetyl)-4-hydroxy-chromen-2-one. Synthesis of 3-(thiazol-4-yl)-4-hydroxy coumarines
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3-Acetyl-4-hydroxy-chromen-2-one (1) was brominated with phenyltrimethylammonium tribromide to afford 3-(2-bromoacetyl)-4-hydroxy- chromen-2-one (2) whose reactions with thiourea, thioacetamide and ammonium dithiocarbamate gave respectively 3-(2-amino-thiazol-4-yl)-4-hydroxy-, 4-hydroxy-3-(2-phenyl-thiazol-4-yl)- and 4-hydroxy-3-(2-mercapto-thiazol-4-yl) chromen-2-one. In a similar manner, compound 2 was treated with four 1-substituted-2-thioureas and thiobenzamide to give the corresponding 4-hydroxy-3-(thiazol-4-yl)-chromen-2-one derivatives.
- Sukdolak,Solujic,Manojlovic,Vukovic,Krstic
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p. 593 - 596
(2007/10/03)
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- Ring closure reactions of 3-arylhydrazonoalkyl-quinolin-2-ones to 1-aryl-pyrazolo[4,3-c]quinolin-2-ones
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4-Hydroxy-3-arylhydrazonoalkyl-2-quinolones 6 or reactive derivatives such as 3-arylhydrazonoalkyl-4-tosyloxy-2-quinolones 7 or 4-chloro-3- arylhydrazonoalkyl-2-quinolones 14, which are obtained via 3-acyl-4- hydroxyquinolones 4, 10 or 3-phenylaminomethylene-quinoline-2,4-diones 12, cyclize in excellent yields to 1-aryl-pyrazolo[4,3-c]quinolin-4-ones (11). The cyclization conditions were investigated by differential scanning calorimetry (DSC).
- Stadlbauer, Wolfgang,Hojas, Gerhard
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p. 681 - 690
(2007/10/03)
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- Efficient synthesis of trisubstituted [1]benzopyrano[4,3-b]pyrrol-4(1H)-one derivatives from 4-hydroxycoumarin
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Various trisubstituted [1]benzopyrano[4,3-b]pyrrol-4(1H)-one derivatives have been synthesized from 4-hydroxycoumarin with a 30-40% yield over six steps. The key step of the synthesis is a base-promoted intramolecular cyclization of enamines 5, followed by dehydration to generate the fused pyrrole ring.
- Liao, Yuan-Xiu,Kuo, Pei-Yu,Yang, Ding-Yah
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p. 1599 - 1602
(2007/10/03)
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- Intermolecular character of the Fris rearrangement in the series of acyloxycoumarins
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In the study of the Fris rearrangement in the series of 7-and 4-acyloxycoumarins we obtained certain data indicating intermolecular character of the rearrangement. The Fris rearrangement of a mixture of 7-benzoyloxy-4-metylcoumarin and 7-acetoxycoumarin results in formation of four reaction products in approximately equal molar ratio. Also, four products were obtained in the Fris rearrangement of 7-and 4-acyloxycoumarins in the presence of hydroxycoumarins. The Fris rearrangement of acyloxycoumarins in the presence of m-xylene at acylcoumarin-m-xylene ratio of 1:6 leads to the corresponding hydroxycoumarins and acylated m-xylenes. Intermediate formation of acylium ions was also detected by evolution of carbon monooxide at the Fris rearrangement of 7-pyvaloyloxy-and 7-isobutyryloxy-4-methylcoumarins. A product of intermolecular migration, 3-acetyl-4-hydoxy-6-methylcoumarin, was discovered also in the rearrangement of 4-acetoxycoumarin in the presence of 4-hydoxy-6-methylcoumarin catalyzed by phosphorus oxychloride.
- Kravchenko,Chibisova,Traven'
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p. 899 - 909
(2007/10/03)
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- Heterocyclic dyestuffs
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Dyestuffs of the formula STR1 wherein R1, R2, R denote H, alkyl, alkenyl, cycloalkyl, aralkyl etc. R3, R4 denote H, alkyl, aralkyl, aryl, alkoxy, halogen, CN, COOH, alkoxycarbonyl, alkylsulfonyl, arylsulfonyl etc. Z denotes O, S or --N(R)--, p and q denote 0 or 1, but not simultaneously 0 and G stands for the remaining members of a ring system, with the proviso that R3 is not alkyl if G is a thiazole ring, are outstanding suitable for dyeing fibre materials of all kinds in clear yellow to violet shades with good fastness properties.
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- NOUVEAU MODE DE CYCLYSATION DE CETO-YLURES. APPLICATION A UNE SYNTHESE IGINALE D'ACYL-3 HYDROXY-4-COUMARINES ET DE L'HYDROXY-11 BENZO-(b) 12 XANTHONE-12
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The thermal decomposition of keto-ylides resulting from the reaction of m- and p-acetoxy benzoyl chlorides with Ph3P=CH-COOMe leads, after saponification to m- and p-phenylpropiolic acid respectively.Ortho substitution by an acyl group generally changes the orientation of the reaction.Thus o-acetoxy-, benzoyloxy- or phenylacetoxy benzoyl chlorides respectively afford: and (R=Me,Ph) in satisfactory yields.Saponification of the first and second ones gives: (R=Me, Ph).This constitutes a new, convenient route to 3-acyl 4-hydroxy cumarins and 11-hydroxy 12H-benzoxanthene 12-one.Formation of these last products involves the carbonyl of the acyloxy-substituent and not of the acyl chloride as previously observed in these series.
- Babin, P.,Dunogues, J.,Petraud, M.
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p. 1131 - 1139
(2007/10/02)
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