Pyrroles: Azoles of one NITROGEN and two double bonds that have aromatic chemical properties.Calixarenes: Phenolic metacyclophanes derived from condensation of PHENOLS and ALDEHYDES. The name derives from the vase-like molecular structures. A bracketed [n] indicates the number of aromatic rings.Nylons: Polymers where the main polymer chain comprises recurring amide groups. These compounds are generally formed from combinations of diamines, diacids, and amino acids and yield fibers, sheeting, or extruded forms used in textiles, gels, filters, sutures, contact lenses, and other biomaterials.Porphyrins: A group of compounds containing the porphin structure, four pyrrole rings connected by methine bridges in a cyclic configuration to which a variety of side chains are attached. The nature of the side chain is indicated by a prefix, as uroporphyrin, hematoporphyrin, etc. The porphyrins, in combination with iron, form the heme component in biologically significant compounds such as hemoglobin and myoglobin.Molecular Structure: The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.Distamycins: Oligopeptide antibiotics from Streptomyces distallicus. Their binding to DNA inhibits synthesis of nucleic acids.Hexanes: Six-carbon saturated hydrocarbon group of the methane series. Include isomers and derivatives. Various polyneuropathies are caused by hexane poisoning.Pyrrolizidine Alkaloids: A group of ALKALOIDS, characterized by a nitrogen-containing necine, occurring mainly in plants of the BORAGINACEAE; COMPOSITAE; and LEGUMINOSAE plant families. They can be activated in the liver by hydrolysis of the ester and desaturation of the necine base to reactive electrophilic pyrrolic CYTOTOXINS.BenzaldehydesMonocrotaline: A pyrrolizidine alkaloid and a toxic plant constituent that poisons livestock and humans through the ingestion of contaminated grains and other foods. The alkaloid causes pulmonary artery hypertension, right ventricular hypertrophy, and pathological changes in the pulmonary vasculature. Significant attenuation of the cardiopulmonary changes are noted after oral magnesium treatment.Palladium: A chemical element having an atomic weight of 106.4, atomic number of 46, and the symbol Pd. It is a white, ductile metal resembling platinum, and following it in abundance and importance of applications. It is used in dentistry in the form of gold, silver, and copper alloys.Hexanones: 6-carbon straight-chain or branched ketones.IminesHeterocyclic Compounds: Ring compounds having atoms other than carbon in their nuclei. (Grant & Hackh's Chemical Dictionary, 5th ed)Cyclization: Changing an open-chain hydrocarbon to a closed ring. (McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)Pyrrolnitrin: 3-Chloro-4-(3-chloro-2-nitrophenyl)pyrrole. Antifungal antibiotic isolated from Pseudomonas pyrrocinia. It is effective mainly against Trichophyton, Microsporium, Epidermophyton, and Penicillium.Furans: Compounds with a 5-membered ring of four carbons and an oxygen. They are aromatic heterocycles. The reduced form is tetrahydrofuran.Rhodium: Rhodium. A hard and rare metal of the platinum group, atomic number 45, atomic weight 102.905, symbol Rh. (Dorland, 28th ed)Netropsin: A basic polypeptide isolated from Streptomyces netropsis. It is cytotoxic and its strong, specific binding to A-T areas of DNA is useful to genetics research.Alkylation: The covalent bonding of an alkyl group to an organic compound. It can occur by a simple addition reaction or by substitution of another functional group.Catalysis: The facilitation of a chemical reaction by material (catalyst) that is not consumed by the reaction.Bile Pigments: Linear TETRAPYRROLES that give a characteristic color to BILE including: BILIRUBIN; BILIVERDIN; and bilicyanin.Palau: A republic consisting of a group of about 100 islands and islets in the western Pacific Ocean. Its capital is Koror. Under Spain it was administered as a part of the Caroline Islands but was sold to Germany in 1899. Seized by Japan in 1914, it was taken by the Allies in World War II in 1944. In 1947 it became part of the U.S. Trust Territory of the Pacific Islands, became internally self-governing in 1980, obtained independent control over its foreign policy (except defense) in 1986, and achieved total independence October 1, 1994. (Webster's New Geographical Dictionary, 1988, p915; telephone communication with Randy Flynn, Board on Geographic Names, 17 January 1995)Magnetic Resonance Spectroscopy: Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).Agelas: A genus of large, brightly colored SPONGES in the family Agelasidae, possessing a skeleton of spongin fibers with a core of large spicules (megascleres).Microwaves: That portion of the electromagnetic spectrum from the UHF (ultrahigh frequency) radio waves and extending into the INFRARED RAYS frequencies.Stereoisomerism: The phenomenon whereby compounds whose molecules have the same number and kind of atoms and the same atomic arrangement, but differ in their spatial relationships. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)Phosphines: Inorganic or organic compounds derived from phosphine (PH3) by the replacement of H atoms. (From Grant & Hackh's Chemical Dictionary, 5th ed)Biliverdine: 1,3,6,7-Tetramethyl-4,5-dicarboxyethyl-2,8-divinylbilenone. Biosynthesized from hemoglobin as a precursor of bilirubin. Occurs in the bile of AMPHIBIANS and of birds, but not in normal human bile or serum.KetonesMolecular Conformation: The characteristic three-dimensional shape of a molecule.Alkynes: Hydrocarbons with at least one triple bond in the linear portion, of the general formula Cn-H2n-2.Polymers: Compounds formed by the joining of smaller, usually repeating, units linked by covalent bonds. These compounds often form large macromolecules (e.g., BIOPOLYMERS; PLASTICS).Models, Molecular: Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.Anions: Negatively charged atoms, radicals or groups of atoms which travel to the anode or positive pole during electrolysis.Peplomycin: An antineoplastic agent derived from BLEOMYCIN.Indoles: Benzopyrroles with the nitrogen at the number one carbon adjacent to the benzyl portion, in contrast to ISOINDOLES which have the nitrogen away from the six-membered ring.Alkenes: Unsaturated hydrocarbons of the type Cn-H2n, indicated by the suffix -ene. (Grant & Hackh's Chemical Dictionary, 5th ed, p408)Ferricyanides: Inorganic salts of the hypothetical acid, H3Fe(CN)6.Aldehydes: Organic compounds containing a carbonyl group in the form -CHO.Organometallic Compounds: A class of compounds of the type R-M, where a C atom is joined directly to any other element except H, C, N, O, F, Cl, Br, I, or At. (Grant & Hackh's Chemical Dictionary, 5th ed)Heme: The color-furnishing portion of hemoglobin. It is found free in tissues and as the prosthetic group in many hemeproteins.Etomidate: Imidazole derivative anesthetic and hypnotic with little effect on blood gases, ventilation, or the cardiovascular system. It has been proposed as an induction anesthetic.Protoporphyrins: Porphyrins with four methyl, two vinyl, and two propionic acid side chains attached to the pyrrole rings. Protoporphyrin IX occurs in hemoglobin, myoglobin, and most of the cytochromes.Vinyl CompoundsQuantum Theory: The theory that the radiation and absorption of energy take place in definite quantities called quanta (E) which vary in size and are defined by the equation E=hv in which h is Planck's constant and v is the frequency of the radiation.Amines: A group of compounds derived from ammonia by substituting organic radicals for the hydrogens. (From Grant & Hackh's Chemical Dictionary, 5th ed)Electrochemistry: The study of chemical changes resulting from electrical action and electrical activity resulting from chemical changes.Porifera: The phylum of sponges which are sessile, suspension-feeding, multicellular animals that utilize flagellated cells called choanocytes to circulate water. Most are hermaphroditic. They are probably an early evolutionary side branch that gave rise to no other group of animals. Except for about 150 freshwater species, sponges are marine animals. They are a source of ALKALOIDS; STEROLS; and other complex molecules useful in medicine and biological research.Imidazoles: Compounds containing 1,3-diazole, a five membered aromatic ring containing two nitrogen atoms separated by one of the carbons. Chemically reduced ones include IMIDAZOLINES and IMIDAZOLIDINES. Distinguish from 1,2-diazole (PYRAZOLES).Hydrogen Bonding: A low-energy attractive force between hydrogen and another element. It plays a major role in determining the properties of water, proteins, and other compounds.Binding Sites: The parts of a macromolecule that directly participate in its specific combination with another molecule.Structure-Activity Relationship: The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.Spectrum Analysis, Raman: Analysis of the intensity of Raman scattering of monochromatic light as a function of frequency of the scattered light.Amides: Organic compounds containing the -CO-NH2 radical. Amides are derived from acids by replacement of -OH by -NH2 or from ammonia by the replacement of H by an acyl group. (From Grant & Hackh's Chemical Dictionary, 5th ed)Crystallography, X-Ray: The study of crystal structure using X-RAY DIFFRACTION techniques. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Alkaloids: Organic nitrogenous bases. Many alkaloids of medical importance occur in the animal and vegetable kingdoms, and some have been synthesized. (Grant & Hackh's Chemical Dictionary, 5th ed)Electrodes: Electric conductors through which electric currents enter or leave a medium, whether it be an electrolytic solution, solid, molten mass, gas, or vacuum.Indicators and Reagents: Substances used for the detection, identification, analysis, etc. of chemical, biological, or pathologic processes or conditions. Indicators are substances that change in physical appearance, e.g., color, at or approaching the endpoint of a chemical titration, e.g., on the passage between acidity and alkalinity. Reagents are substances used for the detection or determination of another substance by chemical or microscopical means, especially analysis. Types of reagents are precipitants, solvents, oxidizers, reducers, fluxes, and colorimetric reagents. (From Grant & Hackh's Chemical Dictionary, 5th ed, p301, p499)DNA: A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).Spectrophotometry: The art or process of comparing photometrically the relative intensities of the light in different parts of the spectrum.G-Quadruplexes: Higher-order DNA and RNA structures formed from guanine-rich sequences. They are formed around a core of at least 2 stacked tetrads of hydrogen-bonded GUANINE bases. They can be formed from one two or four separate strands of DNA (or RNA) and can display a wide variety of topologies, which are a consequence of various combinations of strand direction, length, and sequence. (From Nucleic Acids Res. 2006;34(19):5402-15)Thermodynamics: A rigorously mathematical analysis of energy relationships (heat, work, temperature, and equilibrium). It describes systems whose states are determined by thermal parameters, such as temperature, in addition to mechanical and electromagnetic parameters. (From Hawley's Condensed Chemical Dictionary, 12th ed)Calorimetry: The measurement of the quantity of heat involved in various processes, such as chemical reactions, changes of state, and formations of solutions, or in the determination of the heat capacities of substances. The fundamental unit of measurement is the joule or the calorie (4.184 joules). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Isomerism: The phenomenon whereby certain chemical compounds have structures that are different although the compounds possess the same elemental composition. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)Oxides: Binary compounds of oxygen containing the anion O(2-). The anion combines with metals to form alkaline oxides and non-metals to form acidic oxides.Models, Chemical: Theoretical representations that simulate the behavior or activity of chemical processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.Oxidation-Reduction: A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).Solvents: Liquids that dissolve other substances (solutes), generally solids, without any change in chemical composition, as, water containing sugar. (Grant & Hackh's Chemical Dictionary, 5th ed)Spectrum Analysis: The measurement of the amplitude of the components of a complex waveform throughout the frequency range of the waveform. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Chromatography, Gas: Fractionation of a vaporized sample as a consequence of partition between a mobile gaseous phase and a stationary phase held in a column. Two types are gas-solid chromatography, where the fixed phase is a solid, and gas-liquid, in which the stationary phase is a nonvolatile liquid supported on an inert solid matrix.Ions: An atom or group of atoms that have a positive or negative electric charge due to a gain (negative charge) or loss (positive charge) of one or more electrons. Atoms with a positive charge are known as CATIONS; those with a negative charge are ANIONS.Chromatography, High Pressure Liquid: Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.Chemistry: A basic science concerned with the composition, structure, and properties of matter; and the reactions that occur between substances and the associated energy exchange.

Prior exposure to neurotrophins blocks inhibition of axonal regeneration by MAG and myelin via a cAMP-dependent mechanism. (1/4084)

MAG is a potent inhibitor of axonal regeneration. Here, inhibition by MAG, and myelin in general, is blocked if neurons are exposed to neurotrophins before encountering the inhibitor; priming cerebellar neurons with BDNF or GDNF, but not NGF, or priming DRG neurons with any of these neurotrophins blocks inhibition by MAG/myelin. Dibutyryl cAMP also overcomes inhibition by MAG/myelin, and cAMP is elevated by neurotrophins. A PKA inhibitor present during priming abrogates the block of inhibition. Finally, if neurons are exposed to MAG/myelin and neurotrophins simultaneously, but with the Gi protein inhibitor, inhibition is blocked. We suggest that priming neurons with particular neurotrophins elevates cAMP and activates PKA, which blocks subsequent inhibition of regeneration and that priming is required because MAG/myelin activates a Gi protein, which blocks increases in cAMP. This is important for encouraging axons to regrow in vivo.  (+info)

Increased lipophilicity and subsequent cell partitioning decrease passive transcellular diffusion of novel, highly lipophilic antioxidants. (2/4084)

Oxidative stress is considered a cause or propagator of acute and chronic disorders of the central nervous system. Novel 2, 4-diamino-pyrrolo[2,3-d]pyrimidines are potent inhibitors of iron-dependent lipid peroxidation, are cytoprotective in cell culture models of oxidative injury, and are neuroprotective in brain injury and ischemia models. The selection of lead candidates from this series required that they reach target cells deep within brain tissue in efficacious amounts after oral dosing. A homologous series of 26 highly lipophilic pyrrolopyrimidines was examined using cultured cell monolayers to understand the structure-permeability relationship and to use this information to predict brain penetration and residence time. Pyrrolopyrimidines were shown to be a more permeable structural class of membrane-interactive antioxidants where transepithelial permeability was inversely related to lipophilicity or to cell partitioning. Pyrrole substitutions influence cell partitioning where bulky hydrophobic groups increased partitioning and decreased permeability and smaller hydrophobic groups and more hydrophilic groups, especially those capable of weak hydrogen bonding, decreased partitioning, and increased permeability. Transmonolayer diffusion for these membrane-interactive antioxidants was limited mostly by desorption from the receiver-side membrane into the buffer. Thus, in this case, these in vitro cell monolayer models do not adequately mimic the in vivo situation by underestimating in vivo bioavailability of highly lipophilic compounds unless acceptors, such as serum proteins, are added to the receiving buffer.  (+info)

Involvement of phosphodiesterase-cGMP-PKG pathway in intracellular Ca2+ oscillations in pituitary GH3 cells. (3/4084)

The present study investigates the potential role of the Ca2+-calmodulin-dependent type I phosphodiesterase (PDE)-cGMP-protein kinase G (PKG) pathway in spontaneous [Ca2+]i oscillations in GH3 cells using fura-2 single cell videoimaging. Vinpocetine (2.5-50 microM), a selective inhibitor of type I PDE, induced a concentration-dependent inhibition of spontaneous [Ca2+]i oscillations in these pituitary cells, and at the same time produced an increase of the intracellular cGMP content. The cell permeable cGMP analog N2,2'-O-dibutyryl-cGMP (dB-cGMP) (1 mM) caused a progressive reduction of the frequency and the amplitude of spontaneous [Ca2+]i oscillations when added to the medium. KT5823 (400 nM), a selective inhibitor of cGMP-dependent protein kinase (PKG), produced an increase of baseline [Ca2+]i and the disappearance of spontaneous [Ca2+]i oscillations. When KT5823 was added before vinpocetine, the PKG inhibitor counteracted the [Ca2+]i lowering effect of the cGMP catabolism inhibitor. Finally, the removal of extracellular Ca2+ or the blockade of L-type voltage-sensitive calcium channels (VSCC) by nimodipine produced a decrease of cytosolic cGMP levels. Collectively, the results of the present study suggest that spontaneous [Ca2+]i oscillations in GH3 cells may be regulated by the activity of type I PDE-cGMP-PKG pathway.  (+info)

Characterization of a novel, non-peptidyl antagonist of the human glucagon receptor. (4/4084)

We have identified a series of potent, orally bioavailable, non-peptidyl, triarylimidazole and triarylpyrrole glucagon receptor antagonists. 2-(4-Pyridyl)-5-(4-chlorophenyl)-3-(5-bromo-2-propyloxyphenyl)p yrr ole (L-168,049), a prototypical member of this series, inhibits binding of labeled glucagon to the human glucagon receptor with an IC50 = 3. 7 +/- 3.4 nM (n = 7) but does not inhibit binding of labeled glucagon-like peptide to the highly homologous human glucagon-like peptide receptor at concentrations up to 10 microM. The binding affinity of L-168,049 for the human glucagon receptor is decreased 24-fold by the inclusion of divalent cations (5 mM). L-168,049 increases the apparent EC50 for glucagon stimulation of adenylyl cyclase in Chinese hamster ovary cells expressing the human glucagon receptor and decreases the maximal glucagon stimulation observed, with a Kb (concentration of antagonist that shifts the agonist dose-response 2-fold) of 25 nM. These data suggest that L-168,049 is a noncompetitive antagonist of glucagon action. Inclusion of L-168, 049 increases the rate of dissociation of labeled glucagon from the receptor 4-fold, confirming that the compound is a noncompetitive glucagon antagonist. In addition, we have identified two putative transmembrane domain residues, phenylalanine 184 in transmembrane domain 2 and tyrosine 239 in transmembrane domain 3, for which substitution by alanine reduces the affinity of L-168,049 46- and 4. 5-fold, respectively. These mutations do not alter the binding of labeled glucagon, suggesting that the binding sites for glucagon and L-168,049 are distinct.  (+info)

Characterization of the pyoluteorin biosynthetic gene cluster of Pseudomonas fluorescens Pf-5. (5/4084)

Ten genes (plt) required for the biosynthesis of pyoluteorin, an antifungal compound composed of a bichlorinated pyrrole linked to a resorcinol moiety, were identified within a 24-kb genomic region of Pseudomonas fluorescens Pf-5. The deduced amino acid sequences of eight plt genes were similar to the amino acid sequences of genes with known biosynthetic functions, including type I polyketide synthases (pltB, pltC), an acyl coenzyme A (acyl-CoA) dehydrogenase (pltE), an acyl-CoA synthetase (pltF), a thioesterase (pltG), and three halogenases (pltA, pltD, and pltM). Insertions of the transposon Tn5 or Tn3-nice or a kanamycin resistance gene in each of these genes abolished pyoluteorin production by Pf-5. The presumed functions of the eight plt products are consistent with biochemical transformations involved in pyoluteorin biosynthesis from proline and acetate precursors. Isotope labeling studies demonstrated that proline is the primary precursor to the dichloropyrrole moiety of pyoluteorin. The deduced amino acid sequence of the product of another plt gene, pltR, is similar to those of members of the LysR family of transcriptional activators. pltR and pltM are transcribed divergently from the pltLABCDEFG gene cluster, and a sequence with the characteristics of a LysR binding site was identified within the 486-bp intergenic region separating pltRM from pltLABCDEFG. Transcription of the pyoluteorin biosynthesis genes pltB, pltE, and pltF, assessed with transcriptional fusions to an ice nucleation reporter gene, was significantly greater in Pf-5 than in a pltR mutant of Pf-5. Therefore, PltR is proposed to be a transcriptional activator of linked pyoluteorin biosynthesis genes.  (+info)

Promotion of antibiotic production by high ethanol, high NaCl concentration, or heat shock in Pseudomonas fluorescens S272. (6/4084)

A stress imposed by a continuous feed of high ethanol, high NaCl concentration, or a high temperature shock increased antibiotic production by several times in Pseudomonas fluorescens S272. A tentative bioassay showed that the stress caused about 40-fold elevation in the autoinducer activity. Addition of synthetic autoinducers, N-(3-oxododecanoyl)-L-homoserine lactone or N-(3-oxohexanoyl)-L-homoserine lactone at a concentration of more than 100 micrograms/l to a non-stressed culture also increased the antibiotic production by several times. These results suggested that the antibiotic production in P. fluorescens S272 was regulated by N-acyl-homoserine lactone and the promotive effect by stress occurred through any function that increased the autoinducer production.  (+info)

Peripheral urocortin delays gastric emptying: role of CRF receptor 2. (7/4084)

Urocortin, a new mammalian member of the corticotropin-releasing factor (CRF) family has been proposed to be the endogenous ligand for CRF receptor 2 (CRF-R2). We studied the influence of intravenous urocortin on gastric emptying and the role of CRF-R2 in peptide action and postoperative gastric ileus in conscious rats. The intravenous doses of rat CRF and rat urocortin producing 50% inhibition of gastric emptying were 2.5 and 1.1 microgram/kg, respectively. At these intravenous doses, CRF and urocortin have their actions fully reversed by the CRF-R1/CRF-R2 antagonist astressin at antagonist/agonist ratios of 5:1 and 67:1, respectively. Astressin (12 microgram/kg iv) completely prevented abdominal surgery-induced 54% inhibition of gastric emptying 3 h after surgery while having no effect on basal gastric emptying. The selective nonpeptide CRF-R1 antagonists antalarmin (20 mg/kg ip) and NBI-27914 (400 microgram/kg iv) did not influence intravenous CRF-, urocortin- or surgery-induced gastric stasis. These results as well as earlier ones showing that alpha-helical CRF9-41 (a CRF-R2 more selective antagonist) partly prevented postoperative ileus indicate that peripheral CRF-R2 may be primarily involved in intravenous urocortin-, CRF-, and abdominal surgery-induced gastric stasis.  (+info)

Inhibition of PC-3 human androgen-independent prostate cancer and its metastases by cytotoxic somatostatin analogue AN-238. (8/4084)

We evaluated whether AN-238, the cytotoxic analogue of somatostatin (SST) consisting of the radical 2-pyrrolinodoxorubicin (AN-201) linked covalently to the SST octapeptide carrier RC-121 (D-Phe-Cys-Tyr-D-Trp-Lys-Val-Cys-Thr-NH2), could be used for targeting human primary and metastatic prostate carcinomas that express SST receptors (SSTRs). The antitumor activity and toxicity of AN-238 and its components were first characterized in nude mice bearing s.c. xenografts of PC-3 human androgen-independent prostate cancer. In experiment 1, AN-238 was injected once i.v. at 200 nmol/kg when the mean volume of s.c. tumors was about 30 mm3. Administration of AN-238 inhibited tumor growth, as shown by a 74% decrease in tumor volume and by a 71% reduction in tumor weight after 7 weeks as compared with the control group. AN-201 at an equimolar dose did not show any antitumor activity. The mortality was 14.3% (one of seven mice) in the AN-238-treated group and 47% (three of seven mice) in mice that received AN-201. In experiment 2, two i.v. injections of AN-238 at 150 nmol/kg were given 10 days apart when the tumors measured 65-70 mm3. A significant inhibition of tumor volume (62.3%; P < 0.001) and tumor weight (61.1%; P < 0.01) was observed after 4 weeks of treatment. AN-201, given alone at the same dose or coadministered with RC-121, had no significant effect on PC-3 tumors. The suppression of tumor growth induced by AN-238 was accompanied by a significant enhancement of apoptosis (P < 0.01). There were similar side effects in all treated groups, which included a transient loss of body weight and leukopenia. The effectiveness of AN-238 in a metastatic model was then investigated in animals implanted orthotopically with 2 x 10(6) PC-3 cells. Two i.v. injections of AN-238 or AN-201 at 150 nmol/kg were administered 10 days apart at 10 weeks after intraprostatic inoculation of PC-3 cells. After 4 weeks of treatment, the mean weight of primary tumors in animals receiving AN-238 was 77% lower (P < 0.01) than that in controls. This reduction was also significantly greater (P < 0.05) than that in animals given AN-201, which showed only a 34% inhibition (nonsignificant versus controls). All control animals and four of six (67%) mice treated with AN-201 developed metastases in the lymph nodes; however, no lymphatic spread of cancer was found in the AN-238-treated group. Using reverse transcription-PCR analysis, we demonstrated the expression of SSTR2 and SSTR5 in intraprostatic tumors and their metastases in lymph nodes as well as in s.c. tumors. The present study demonstrates the high efficacy of SSTR-targeted chemotherapy in a model of advanced human androgen-independent prostatic carcinoma, as shown by the inhibition of primary tumors and their metastases by the cytotoxic SST analogue AN-238.  (+info)

  • Herein, we report a new and facile method for the synthesis of 2,5-di and 2,3,5-trisubstituted pyrrole using intramolecular reductive cyclization of the easily accessible nitrodienes as starting material catalyzed by palladium complex and with carbon monoxide as a reductant. (omicsonline.org)
  • Generally, pharmaceuticals containing pyrroles are of high value as biological agents such as sunitinib (anti-tumor), ketorolac (analgesic) and the highly successful cholesterol-lowering drug atorvastatin calcium (Lipitor), which is notable as the first drug to earn in excess of $1 billion of sales in its first year. (omicsonline.org)
  • McCluskey, A. The influence of ionic liquids on the Knoevenagel condensation of 1H-pyrrole-2-carbaldehyde with phenyl acetonitriles - cytotoxic 3-substituted-(1H-pyrrol-2-yl)acrylonitriles. (alfa.com)
  • In the mol-ecule of the title compound, C 22 H 17 ClN 2 O 2 , the dihedral angles formed by the pyrrole ring with the quinoline and phenyl rings are 67.93 (8) and 28.40 (11)°, respectively. (pubmedcentralcanada.ca)
  • The electronic properties of pyrrole are important in the context of conducting polymers, where poly-pyrroles have found many useful applications. (omicsonline.org)
  • Herein, we investigate the kinetics of the redox processes occurring in acidic aqueous electrolyte in electropolymerized poly(pyrrol-3-ylhydroquinone), which has been proposed for electrical energy storage applications. (diva-portal.org)
  • In poly(pyrrol-3-ylhydroquinone), a polypyrrole derivative functionalized with hydroquinone units, the redox conversion of the pendant groups has a large impact on the polymer backbone. (diva-portal.org)
  • Moreover, a series of quinone-pyrrole dyad polymers with various linkers was synthesized, showing that the choice of linker has a pronounced impact on the interactions between the PG and CP. (diva-portal.org)
  • Pyrrole is a heterocyclic aromatic organic compound, a five-membered ring with the formula C4H4NH. (wikipedia.org)
  • designated as pyrrole-2-carboxylate monooxygenase belongs to the recently discovered new class of two-component flavin aromatic monooxygenases. (nih.gov)
  • All H-atoms were positioned geometrically and refined using a riding model with d(N-H) = 0.88 Å, U iso (H) = 1.2 U eq (C) for pyrrole N, d(C-H) = 0.95 Å, U iso (H) = 1.2 U eq (C) for aromatic C and d(C-H) = 0.99 Å, U iso (H) = 1.2 U eq (C) for CH 2 groups. (pubmedcentralcanada.ca)
  • The Van Leusen reaction can be used to form pyrroles, by reaction of tosylmethyl isocyanide (TosMIC) with an enone in the presence of base, in a Michael addition. (wikipedia.org)
  • A library of substituted pyrrole analogs can be quickly produced by using continuous flow chemistry (reaction times of around 8 min. (wikipedia.org)
  • It undergoes condensation reaction to produce pyrrole-2-carboxaldehyde salicylhydrazone (PCSH). (alfa.com)
  • The mild reaction conditions of the palladium-copper coupling-isomerization reaction open a highly convergent, chromogenic route to blue emissive pyrroles in the sense of a consecutive four-component reaction. (frontiersin.org)
  • In our previous studies we showed antitumor and anti-inflammatory activities of protein kinases inhibitor pyrrol derivate 1-(4-Cl-benzyl)-3-Cl-4-(CF3-fenylamino)-1H-pyrrol-2,5-dione (MI-1) on rat colon cancer model. (hindawi.com)
  • Porphobilinogen, a trisubstituted pyrrole, is the biosynthetic precursor to many natural products such as heme. (wikipedia.org)
  • Biologically, pyrroles tend to construct the key structure of porphyrin rings, which act as an active moiety in chlorophyll, heme, vitamin B12 or bile pigments [ 2 ]. (alliedacademies.org)
  • Two series of 1-alkyl-2-aryl-4-(1-naphthoyl)pyrroles were synthesized and their affinities for the cannabinoid CB, and CB2 receptors were determined. (rti.org)
  • Most efficient reductions of alkyl pyrroles require an acid as the solvent or as a component of the solvent mixture. (docme.ru)
  • Precursor labeling studies of some of these natural products have shown that L-proline can serve as the biosynthetic precursor for these moieties, including those found in coumermycin A 1 , pyoluteorin, and one of the pyrroles of undecylprodigiosin. (mendeley.com)
  • 3-(Ethoxycarbonyl)-2,5-dihydro-4-hydroxy-2-oxo-1H-pyrrole-1-acetic acid ethyl ester (CAS 62613-79-0) Market Research Report 2018 aims at providing comprehensive data on 3-(ethoxycarbonyl)-2,5-dihydro-4-hydroxy-2-oxo-1h-pyrrole-1-acetic acid ethyl ester market globally and regionally (Europe, Asia, North America, Latin America etc. (marketpublishers.com)
  • The report includes 3-(ethoxycarbonyl)-2,5-dihydro-4-hydroxy-2-oxo-1h-pyrrole-1-acetic acid ethyl ester description, covers its application areas, manufacturing methods, patents. (marketpublishers.com)
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  • In addition to the above the report determines 3-(ethoxycarbonyl)-2,5-dihydro-4-hydroxy-2-oxo-1h-pyrrole-1-acetic acid ethyl ester consumers. (marketpublishers.com)
  • 3-(Ethoxycarbonyl)-2,5-dihydro-4-hydroxy-2-oxo-1H-pyrrole-1-acetic acid ethyl ester (CAS 62613-79-0) Market Research Report 2018 contents were prepared and placed on the website in March, 2018. (marketpublishers.com)
  • This establishes a novel mechanism for pyrrole biosynthesis and extends the hypothesis that organisms use A/PCP pairs to partition an amino acid into secondary metabolism. (mendeley.com)
  • Some individuals may excrete more HPL (pyrroles) than others, which indicates a toxic level of the enzyme in their body. (healthline.com)
  • New pyrrole-based histone deacetylase inhibitors: binding mode, enzyme- and cell-based investigations. (nih.gov)
  • Two of the pyrrole carboxamides, PSI2106 and MDF2085, were especially notable in vitro inhibitors of recombinant human MKP-1 enzyme activity with IC 50 values of 8.0 ± 0.9 and 8.3 ± 0.8 μM, respectively. (aspetjournals.org)
  • Pyrroles are utilized as a catalyst for polymerization process, corrosion inhibitor, preservative, solvent for resins and terpenes. (alliedacademies.org)
  • Two clinical examples of pyrroles displaying this pattern of substitution are amtolmetin and tolmetin (non-steroidal anti-inflammatory agents). (omicsonline.org)
  • It is also used to prepare 4-Difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY dyes) through condensation with a pyrrole, which is an important probes for biotechnology and other applications. (alfa.com)
  • These intermediates are further converted to a wide range of polysubstituted pyrroles through double bond transposition and Alder-ene reactions. (organic-chemistry.org)
  • Density Functional Theory (DFT) studies suggest that these reactions proceed via initial activation of the pyrrole C-3 position before undergoing subsequent rearrangement, contradicting the conventional wisdom that pyrroles are more nucleophilic through C-2. (whiterose.ac.uk)
  • Pyrroles can be prepared by silver-catalyzed cyclization of alkynes with isonitriles, where R2 is an electron-withdrawing group, and R1 is an alkane, aryl group, or ester. (wikipedia.org)
4-[2-(4-Fluoro-phenyl)-5-phenyl-1H-pyrrol-3-yl]-pyridine | C21H15FN2 - PubChem
4-[2-(4-Fluoro-phenyl)-5-phenyl-1H-pyrrol-3-yl]-pyridine | C21H15FN2 - PubChem (pubchem.ncbi.nlm.nih.gov)
3S)-1-[(3Z)-3-[(3-Methoxy-1H-pyrrol-2-yl)methylidene]-5-nitro-2-oxo-1H-indol-4-yl]pyrrolidine-3-carboxamide | C19H19N5O5 -...
3S)-1-[(3Z)-3-[(3-Methoxy-1H-pyrrol-2-yl)methylidene]-5-nitro-2-oxo-1H-indol-4-yl]pyrrolidine-3-carboxamide | C19H19N5O5 -... (pubchem.ncbi.nlm.nih.gov)
2-{(2E)-2-[(1-Methyl-1H-pyrrol-2-yl)methylene]hydrazino}-4-oxo-4,5-dihydro-1,3-thiazol-5-yl)acetic acid | C11H12N4O3S |...
2-{(2E)-2-[(1-Methyl-1H-pyrrol-2-yl)methylene]hydrazino}-4-oxo-4,5-dihydro-1,3-thiazol-5-yl)acetic acid | C11H12N4O3S |... (chemspider.com)
2-Azido-N-methyl-1H-pyrrole-3-sulfonamide | C5H7N5O2S - PubChem
2-Azido-N-methyl-1H-pyrrole-3-sulfonamide | C5H7N5O2S - PubChem (pubchem.ncbi.nlm.nih.gov)
1H-pyrrole epitope - Immune Epitope Database (IEDB)
1H-pyrrole epitope - Immune Epitope Database (IEDB) (iedb.org)
Antitumor Activity of a 5-Hydroxy-1H-Pyrrol-2-(5H)-One-Based Synthetic Small Molecule In Vitro and In Vivo
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2S)-2-(1H-Pyrrol-2-yl)pent-4-en-2-amine | C9H14N2 - PubChem
2S)-2-(1H-Pyrrol-2-yl)pent-4-en-2-amine | C9H14N2 - PubChem (pubchem.ncbi.nlm.nih.gov)
6-((2-(2-Chlorophenyl)-5-(4-(pyridin-4-yloxy)phenyl)-1H-pyrrol-1-yl)methyl)pyridin-2-amine | C27H21ClN4O - PubChem
6-((2-(2-Chlorophenyl)-5-(4-(pyridin-4-yloxy)phenyl)-1H-pyrrol-1-yl)methyl)pyridin-2-amine | C27H21ClN4O - PubChem (pubchem.ncbi.nlm.nih.gov)
Methyl (1-methyl-5-oxo-4,5-dihydro-1H-pyrrol-2-YL)acetate | C8H11NO3 - PubChem
Methyl (1-methyl-5-oxo-4,5-dihydro-1H-pyrrol-2-YL)acetate | C8H11NO3 - PubChem (pubchem.ncbi.nlm.nih.gov)
2H-Pyrrol-4-ol, 3,4-dihydro-2,2,4-trimethyl-5-phenyl-, 1-oxide | C13H17NO2 - PubChem
2H-Pyrrol-4-ol, 3,4-dihydro-2,2,4-trimethyl-5-phenyl-, 1-oxide | C13H17NO2 - PubChem (pubchem.ncbi.nlm.nih.gov)
Could you have Pyrrole disorder?
Could you have Pyrrole disorder? (news.com.au)
Pyrrole
Pyrrole (webbook.nist.gov)
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Pyrrole Disorder: Symptoms, Causes, Diagnosis & Treatment
Pyrrole Disorder: Symptoms, Causes, Diagnosis & Treatment (healthline.com)
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Getting rid of bed bugs: Natural measures, chemicals, and pest control (medicalnewstoday.com)
Interpretation of the Ultraviolet Spectra of Natural Products - 1st Edition
Interpretation of the Ultraviolet Spectra of Natural Products - 1st Edition (elsevier.com)
Golden Heavy Body Acrylic Colour 60ml
Golden Heavy Body Acrylic Colour 60ml (saa.co.uk)
5-pyrrol-1-ylpyridine-3-carboxylic acid
5-pyrrol-1-ylpyridine-3-carboxylic acid (scitoys.com)
Chemistry			News Articles: Chemistry 2011.org
Chemistry News Articles: Chemistry 2011.org (chemistry2011.org)
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