Sample records for 1,4-dihydroxyanthraquinone

  1. Exploring 1,4-dihydroxyanthraquinone as long-range emissive ratiometric fluorescent probe for signaling Zn(2+)/PO4(3-): Ensemble utilization for live cell imaging.


    Sinha, Sougata; Gaur, Pankaj; Mukherjee, Trinetra; Mukhopadhyay, Subhrakanti; Ghosh, Subrata


    Fluorescent 1,4-dihydroxyanthraquinone 1 was found to demonstrate its ratiometric signaling property upon interaction with divalent zinc (Zn(2+)). While the probe itself exhibited fluorescence emission in the yellow region (λem=544 nm and 567 nm), binding with Zn(2+) induced strong emission in the orange region (λem=600 nm) which was mainly due to a combination of CHEF and ICT mechanism. The probe was found to be highly sensitive toward the detection of zinc and the limit of detection (LOD) was calculated to be 9×10(-7) M. The possibility of using this probe for real-time analysis was strongly supported by the striking stability of fluorescence signal for more than five days with similar fluorescence intensity as observed during instant signaling. The present probe works within physiological pH range and is devoid of any interference caused by the same group elements such as Cd(2+)/Hg(2+). The probe possesses excellent excitation/emission wavelength profile and can penetrate cell membrane to image low concentration of zing inside living system. The in situ formed zinc-probe ensemble was further explored as ratiometric sensing platform for detecting another bio-relevant analyte phosphate anion through a zinc-displacement approach.

  2. Synthesis of new cytotoxic aminoanthraquinone derivatives via nucleophilic substitution reactions.


    Nor, Siti Mariam Mohd; Sukari, Mohd Aspollah Hj Md; Azziz, Saripah Salbiah Syed Abdul; Fah, Wong Chee; Alimon, Hasimah; Juhan, Siti Fadilah


    Aminoanthraquinones were successfully synthesized via two reaction steps. 1,4-Dihydroxyanthraquinone (1) was first subjected to methylation, reduction and acylation to give an excellent yield of anthracene-1,4-dione (3), 1,4-dimethoxyanthracene-9,10-dione (5) and 9,10-dioxo-9,10-dihydroanthracene-1,4-diyl diacetate (7). Treatment of 1, 3, 5 and 7 with BuNH2 in the presence of PhI(OAc)2 as catalyst produced seven aminoanthraquinone derivatives 1a, b, 3a, and 5a-d. Amination of 3 and 5 afforded three new aminoanthraquinones, namely 2-(butylamino)anthracene-1,4-dione (3a), 2-(butylamino)anthracene-9,10-dione (5a) and 2,3-(dibutylamino)anthracene-9,10-dione (5b). All newly synthesised aminoanthraquinones were examined for their cytotoxic activity against MCF-7 (estrogen receptor positive human breast) and Hep-G2 (human hepatocellular liver carcinoma) cancer cells using MTT assay. Aminoanthraquinones 3a, 5a and 5b exhibited strong cytotoxicity towards both cancer cell lines (IC50 1.1-13.0 µg/mL).

  3. Decomposition of polycyclic aromatic hydrocarbons in atmospheric aqueous droplets through sulfate anion radicals: an experimental and theoretical study.


    Wang, Degao; Li, Yifan; Yang, Meng; Han, Min


    Polycyclic aromatic hydrocarbons (PAHs) are environmental pollutants that have received considerable attention because of their carcinogenic and mutagenic effects. PAHs can be degraded by sulfate anion radicals in atmospheric aqueous droplets. This study was to investigate the mechanism and degradation products of sulfate anion radical reaction with anthracene (ANT) by experimental and quantum chemical approaches. From these observations of the experiments, the sulfate anion radical is capable of oxidizing ANT rapidly and three intermediates anthraquinone (ATQ), 1-hydroxyanthraquinone (1-hATQ), and 1,4-dihydroxyanthraquinone (1,4-dhATQ) were detected as degradation products by GC-MS. The proposed one-electronic transfer mechanism of sulfate anion radical reaction with ANT was modeled using hybrid density function theory (BHandHLYP) methods. Geometry optimization and vibrational frequency analysis calculation were performed for reactants, transition states, intermediates, and products. The potential energy surfaces of these reactions are explored to establish structures and relative energies of reactants, intermediates, transition states, and products. Computational results suggest that initial electron transfer step is predicted to have activation energy of -3.35 kcal/mol in water, indicating that ANT can be oxidized quickly in atmospheric aqueous droplets. The reaction pathways have been proposed on the basis of these experimental and theoretical findings. The results may provide useful information for a better understanding of the sulfate anion radical-initiated reactions in atmospheric aqueous droplets such as clouds, rains or fogs.

  4. Anthraquinones quinizarin and danthron unwind negatively supercoiled DNA and lengthen linear DNA

    SciTech Connect

    Verebová, Valéria; Adamcik, Jozef; Danko, Patrik; Podhradský, Dušan; Miškovský, Pavol; Staničová, Jana


    Highlights: • Anthraquinones quinizarin and danthron unwind negatively supercoiled DNA. • Anthraquinones quinizarin and danthron lengthen linear DNA. • Anthraquinones quinizarin and danthron possess middle binding affinity to DNA. • Anthraquinones quinizarin and danthron interact with DNA by intercalating mode. - Abstract: The intercalating drugs possess a planar aromatic chromophore unit by which they insert between DNA bases causing the distortion of classical B-DNA form. The planar tricyclic structure of anthraquinones belongs to the group of chromophore units and enables anthraquinones to bind to DNA by intercalating mode. The interactions of simple derivatives of anthraquinone, quinizarin (1,4-dihydroxyanthraquinone) and danthron (1,8-dihydroxyanthraquinone), with negatively supercoiled and linear DNA were investigated using a combination of the electrophoretic methods, fluorescence spectrophotometry and single molecule technique an atomic force microscopy. The detection of the topological change of negatively supercoiled plasmid DNA, unwinding of negatively supercoiled DNA, corresponding to appearance of DNA topoisomers with the low superhelicity and an increase of the contour length of linear DNA in the presence of quinizarin and danthron indicate the binding of both anthraquinones to DNA by intercalating mode.

  5. Hole-Burning Spectroscopy as a Probe of Guest - Interactions in Amorphous Materials.

    NASA Astrophysics Data System (ADS)

    Cavus, Abdullah

    The absorption bands of organic molecules in rigid solvents are, even at low temperatures, quite broad. Typical bandwidths are of the order of several hundreds of wavenumbers. So, condensed phase spectroscopy is limited in its spectral resolution by the inhomogeneous broadening. Irradiation into these inhomogeneously broadened bands with a narrow bandwidth laser can induce resonant molecules to undergo a photochemical or photophysical transformation creating a hole in the absorption spectrum. The systems of concern to us here are those in which photochemically active molecules are present in low concentration as guests in a solid host matrix at low temperatures. When molecules are embedded in amorphous hosts, it is found that the width of spectral lines are highly sensitive to the nature of the guest-host interaction. The advantage of hole-burning spectroscopy is that it provides the ability to obtain high resolution optical spectra in inherently low resolution situations. Measuring the dipole moment change of a guest molecule in various host matrices may shed some light on guest-host interactions involved with the homogeneous linewidth of the guest, temperature and properties of the host. The dipole moment difference, Delta mu_{rm eff}, between guest molecule in the ground state and the excited state was estimated by using the spectral hole splitting or broadening that results from an applied electric field. The fluorescence excitation spectroscopy technique was used to study the photochemical hole-burning and investigate the dipole moment change of quinazirine (1,4-dihydroxyanthraquinone) and cresylviolet perchlorate in various glass and polymer hosts such as formamide, ethanol:methanol (EM), polyvinyl alcohol (PVA), poly(2-hydroxyethyl) methacrylate (PHEMA), polyvinylbutyral (PVB), and polymethyl methacrylate (PMMA). The strong correlation between effective dipole moment change of the guest molecule and the dielectric constant of the host matrices illustrated