Water-soluble sapphyrins

Sapphyrins are provided having appended functional groups that render the sapphyrin water-soluble. Such water-soluble sapphyrins are useful for photodynamic therapy, for example.Board of Regents, University of Texas Syste

Sapphyrin multimers

The present invention provides novel sapphyrin dimers, trimers, oligomers and polymers, which multimers may include repeating units of sapphyrin or sapphyrin derivatives alone, or may further incorporate other units such as nucleobases.Board of Regents, University of Texas Syste

Preprogramming Of Porphyrin-nucleic Acid Assemblies Via Variation Of The Alkyl/aryl Substituents Of Phosphonium Tetratolylporphyrins

Cationic alkyl/arylphosphonium meso-tetratolylporphyrins aggregate in an aqueous solution to form H-aggregates, J-aggregates, and long-range assemblies. The ratio between the monomer and various types of aggregates can be controlled by the substitution in the phosphonium units and by the ionic strength. A trimethylphosphonium derivative is predominantly monomeric, dimethylphenylphosphonium forms monomers as well as low-molecular-weight H- and J-aggregates, triphenylphosphonium forms mainly H- and J-aggregates, and tri(n-butyl)phosphonium forms mainly long-range assemblies. Porphyrin monomers associate with calf thymus DNA (binding constant Kb approximate to 10(7) M-1) and oligonucleotides (K-b approximate to 10(5-)10(6) M-1). The large size of the meso-substituents prevents the intercalation between base pairs. All phosphonium porphyrins described in this study were found to bind to the phosphate backbone of a nucleic acid with a significant preference for A-T base pair sequences. Porphyrin aggregates formed in the solution deposit readily on the surface of the DNA and oligonucleotides without changing their structure and size. Porphyrin monomers bound to DNA and nucleotides have photophysical properties (higher quantum yield of triplet states and singlet oxygen) different from those of porphyrin aggregates

Hydroxylated texaphyrins

A method of using texaphyrins as radiosensitizers. Advantageous properties of texaphyrins for use as a radiosensitizer include i) a low redox potential which allows radiation induced solvated electrons to flow to texaphyrin rather than neutralizing hydroxyl radicals, allowing the hydroxyl radicals to cause cellular damage, ii) a relatively stable texaphyrin radical which, nevertheless, reacts readily to covalently modify neighboring molecules causing further cellular damage, and iii) intrinsic biolocalization and indifference to the presence of O.sub.2 which allow texaphyrin to be particularly effective for treating the hypoxic areas of solid tumors. Sensitizer enhancement ratios of 1.62 and 2.2 were achieved at 20 .mu.M and 80 .mu.M gadolinium-texaphyrin, respectively, with a mouse leukemia cell line. Methods of treatment for an individual having a tumor include the use of a texaphyrin as a radiosensitizer and as an agent for photodynamic tumor therapy, or the use of a texaphyrin for internal and for external ionizing radiation. New water soluble hydroxy-substituted texaphyrins are described.Board of Regents, University of Texas Syste

Method of magnetic resonance image enhancement

Texaphyrins are provided for use as radiation sensitizers. Advantageous properties of texaphyrins for use as a radiation sensitizer include: i) a low redox potential which allows radiation-induced hydrated electrons to flow to texaphyrin rather than neutralizing hydroxyl radicals, allowing hydroxyl radicals to cause cellular damage, ii) a relatively stable texaphyrin radical that reacts readily to covalently modify neighboring molecules causing further cellular damage, iii) intrinsic biolocalization, and iv) indifference to the presence or absence of O.sub.2. These properties allow texaphyrins to be particularly effective for treating the hypoxic areas of solid neoplasms. Methods of treatment for an individual having a neoplasm or atheroma include the use of a texaphyrin as a radiation sensitizer and as an agent for photodynamic tumor therapy, or the use of a texaphyrin for internal and for external ionizing radiation. Novel texaphyrins are provided.Board of Regents, University of Texas Syste

The stereospecificity of flobufen metabolism in isolated guinea pig hepatocytes

BACKGROUND: Flobufen (F) is an original nonsteroidal anti-inflammatory drug with one center of chirality. 4-Dihydroflobufen (DHF), compound with two chiral centers, is the main metabolite of F in microsomes and cytosol in all standard laboratory animals. This work describes the biotransformation of F enantiomers and DHF stereoisomers in isolated male guinea pig hepatocytes. Guinea pigs were chosen with respect to similarities in F metabolism as in Man found earlier. R-F, S-F, (2R;4S)-DHF, (2S;4R)-DHF, (2S;4S)-DHF and (2R;4R)-DHF, structurally very similar compounds, served as substrates in order to observe their interaction with enzymes. Stereospecificity of the respective enzymes was studied in vitro, using hepatocytes monolayer. Chiral HPLC using R,R-ULMO column as chiral stationary phase was used for detection and quantitation of metabolites. RESULTS: (2R;4S)-DHF and (2S;4S)-DHF were the principle stereoisomers detected after incubation with rac-F, R-F and S-F. The ratio of (2R;4S)-DHF/(2S;4S)-DHF ranged from 1.1 to 2.4 depending on the substrate used. (2R;4S)-DHF was the major stereoisomer found after incubation with (2S;4S)-DHF and (2R;4R)-DHF. (2S;4S)-DHF was the principle stereoisomer found after incubation with (2R;4S)-DHF and (2S;4R)-DHF. Besides DHF stereoisomers, other metabolites (M-17203, UM-1 and UM-2) were also detected after incubation of hepatocytes monolayer with F. Interestingly, these metabolites were not found in incubation of all F forms and DHF with fresh liver homogenate. CONCLUSIONS: Different activities and stereospecificities of the respective enzymes were observed for each substrate in primary culture of hepatocytes. Cell integrity is crucial for formation of secondary metabolites M-17203, UM-1 and UM-2

Method of cleaving DNA

The present invention provides various novel covalently modified sapphyrin derivatives and conjugates; polymers including sapphyrin or derivatives thereof; and chromatographic supports including sapphyrins and other expanded porphyrins and derivatives thereof. Disclosed are water soluble sapphyrins, including polyhydroxysapphyrins and sapphyrin-sugar derivatives; sapphyrin-metal chelating conjugates; sapphyrin nucleobase conjugates; oligosapphyrins and polysapphyrins, including sapphyrin dimers, trimers, oligomers and higher polymers; and polymer supported expanded porphyrin compositions, including advantageous rubyrin- and sapphyrin-based chromatography columns and electrophoretic supports. Sapphyrin oligomers and polymers and polymer supported expanded porphyrins, such as, e.g., glass and silica expanded porphyrin constructs, are disclosed which include both repeating units of sapphyrin derivatives alone and which include other units, for example, nucleobases, sapphyrin-nucleobase conjugates and long chain alkyl groups.Board of Regents, University of Texas Syste

Method for separating molecules

The present invention provides various novel covalently modified sapphyrin derivatives and conjugates; polymers including sapphyrin or derivatives thereof; and chromatographic supports including sapphyrins and other expanded porphyrins and derivatives thereof. Disclosed are water soluble sapphyrins, including polyhydroxysapphyrins and sapphyrin-sugar derivatives; sapphyrin-metal chelating conjugates; sapphyrin nucleobase conjugates; oligosapphyrins and polysapphyrins, including sapphyrin dimers, trimers, oligomers and higher polymers; and polymer supported expanded porphyrin compositions, including advantageous rubyrin- and sapphyrin-based chromatography columns and electrophoretic supports. Sapphyrin oligomers and polymers and polymer supported expanded porphyrins, such as, e.g., glass and silica expanded porphyrin constructs, are disclosed which include both repeating units of sapphyrin derivatives alone and which include other units, for example, nucleobases, sapphyrin-nucleobase conjugates and long chain alkyl groups.Board of Regents, University of Texas Syste

Texaphyrin solid supports and devices

The present invention provides various novel matrix-supported texaphyrins in which a polymeric or solid matrix is covalently modified by the addition of one or more texaphyrins or texaphyrin derivatives. Described are methods of making various polymer-supported texaphyrins, including texaphyrin chromatographic supports, and devices such as catheters, as may be used, for example, in the separation of neutral and anionic species and in applications concerning phosphate ester hydrolysis, other catalytic schemes, MRI, and PDT.Board of Regents, University of Texas Syste