Search results for "Xanthenes"
showing 5 items of 25 documents
Structural basis for the potential antitumour activity of DNA-interacting benzo[kl]xanthene lignans
2010
The biological properties and possible pharmacological applications of benzo[kl]xanthene lignans, rare among natural products and synthetic compounds, are almost unexplored. In the present contribution, the possible interaction of six synthetic benzo[kl]xanthene lignans and the natural metabolite rufescidride with DNA has been investigated through a combined STD-NMR and molecular docking approach, paralleled by in vitro biological assays on their antiproliferative activity towards two different cancer cell lines: SW 480 and HepG2. Our data suggest that the benzo[kl]xanthene lignans are suitable lead compounds for the design of DNA selective ligands with potential antitumour properties.
Straightforward access to water-soluble unsymmetrical sulfoxanthene dyes: application to the preparation of far-red fluorescent dyes with large stoke…
2014
An efficient synthesis of water-soluble unsymmetrical sulforhodamine/sulforhodol fluorophores containing a single julolidine fragment is presented. Owing to their valuable spectral properties in aqueous buffers, these dyes, especially those bearing a free aniline or phenol moiety, are valuable components of fluorogenic probes for a variety of biosensing applications. A further extension of this synthetic methodology to unusual phenols, namely 7-N,N-dialkylamino-4-hydroxy coumarins has enabled us to provide a new family water-soluble dyes of large Stokes’ shift with far-red spectral features.
Analysis of fluorescent MRI contrast agent behavior in the liver and thoracic aorta of mice.
2004
To characterize the behavior of magnetofluorescent products injected in mice intravenously.The magnetic resonance imaging (MRI) products were labelled with fluorescent molecules to examine the biodistribution process in vivo and observe them at the cellular level by means of confocal microscopy. Three-dimensional (3D) sequences of images were obtained by spectral analysis of sample preparations in a multiphoton confocal microscope and analyzed by the factor analysis of medical image sequence algorithm, which provides factor curves. Factor images are the result of image-processing methods that utilize information from emission spectra. Preparations are also screened in the counting mode to p…
Synthese von Benzo[b]thioxanthenen
1995
Synthesis of Benzo[b]thioxanthenes Benzo[b]thioxanthenes, heterocyclic compounds related to tetracenes and tetracyclines can be obtained by the reaction of 2H-benzo[b]thiete (1) and 1,4-naphthoquinones (3a–g). The primary cycloadducts 4a–g undergo an autoxidation process leading to the quinones 6a–g. The dihydroxy compound 4e shows an additional isomerization by a tetrafold H transfer (4e 5e′). Another preparative route to benzo[b]thioxanthenes makes use of the cycloadditon reaction of 1 and 1,4-epoxynaphthalenes (7a–d). The primary adducts can be transformed to the title compounds by catalytic dehydration processes (8a–d 9a-d). An alternate regioselective opening of the oxygen bridge can b…
Pigment patterns in mutants affecting the biosynthesis of pteridines and xanthommatin in Drosophila melanogaster.
1986
Eye-color mutants of Drosophila melanogaster have been analyzed for their pigment content and related metabolites. Xanthommatin and dihydroxanthommatin (pigments causing brown eye color) were measured after selective extraction in acidified butanol. Pteridines (pigments causing red eye color) were quantitated after separation of 28 spots by thin-layer chromatography, most of which are pteridines and a few of which are fluorescent metabolites from the xanthommatin pathway. Pigment patterns have been studied in 45 loci. The pteridine pathway ramifies into two double branches giving rise to isoxanthopterin, “drosopterins,” and biopterin as final products. The regulatory relationship among the …