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PubMed2003

Novel naphthalene diimides and a cyclophane thereof: synthesis, characterization, photophysical and electrochemical properties.

Three novel naphthalene diimides (1-3) and a cyclophane (4) containing two naphthalene diimide moieties were synthesized and characterized. In contrast to the absorption spectra, the emission spectra were strongly dependent on the solvent polarity. The excimer-like emission and low fluorescence rate constant suggest the formation of ground state complexes in DMF. All the compounds have low fluorescence quantum yields (0.001-0.012). They undergo reversible electron reduction and oxidation while deltaEp values depend strongly on solvent polarity. The LUMO energy values of 1 (3.76 eV), 2 (3.69 eV), and 3 (3.66 eV) vary with the substituent pattern. The structurally relatively rigid cyclophane 4 exhibits excellent thermal stability, a high glass transition temperature (tg, 102 degrees C) and a low LUMO energy value (3.59 eV). Compound 2 is insoluble in DMF at room temperature, but begins to dissolve at 37 degrees C and could therefore potentially serve as a sensor in temperature-sensing devices.

Electrochemistry↗
PubMed2005

The estimation of physicochemical properties of methyl and other alkyl naphthalenes.

The GLC and HPLC data of Autenrieth and co-workers (P. Dimitriou-Christidis, B. C. Harris, T. J. McDonald, E. Reese and R. L. Autenrieth, Chemosphere, 2003, 52, 869) has been used to obtain solvation descriptors for methyl naphthalenes for use in the Abraham solvation equations. These descriptors are then used to predict a large number of physicochemical properties, of environmental importance. These include solubility in water and the gas-water partition coefficient (equivalent to the Henry's Law constant for the water to gas partition). Predictions are in excellent agreement with those of Autenrieth and co-workers and with experimental observations, where available. Other important predictions are the gas-dry octanol and gas-wet octanol partition coefficients. Descriptors have also been obtained for the ethyl-, propyl- and butyl-naphthalenes which, again, can be used to predict numerous physicochemical properties.

Chemical Phenomena↗
PubMed1998

Segregational and structural instability of recombinant plasmid carrying genes for naphthalene degrading pathway.

The stability of recombinant plasmid carrying genes for naphthalene mineralization was determined. A strain of Pseudomonas putida capable of mineralizing naphthalene (Nap+) via salicylate (Sal+) was isolated, and all regulatory and structural genes for the whole pathway were found to be encoded on a 25 kb EcoRI fragment of an approximately 83 kb plasmid present in this strain. The 25 kb EcoRI fragment was cloned into a tetracycline-resistant (TcR) cloning vector pLAFR3 and the recombinant plasmid, pRKJ3 (Nap+, Sal+, TcR), thus obtained was transferred into the plasmid-free strain Pseudomonas putida KT2442 in order to test the stability of the plasmid. Plasmid pRKJ3 was found to be segregationally and/or structurally unstable, depending on the growth conditions. Two types of novel derivative strains having the phenotypes Nap-, Sal+, TcR and Nap-, Sal-, TcR with specific deletions of approximately 2 kb and 18 kb, respectively, were obtained.

Electrophoresis, Agar Gel↗
PubMed2004

Pilot study on the naphthalene exposure of German adults and children by means of urinary 1- and 2-naphthol levels.

Concentrations of 1- and 2-naphthol were measured in urine of 72 adults and 35 young children from Germany to assess the internal exposure to naphthalene of the general population. Naphthols could be detected in more than 90% of the urine samples. Levels of naphthols (sum of 1- and 2-naphthol) were 4-fold higher in smokers (median: 37.6 microg/g creatinine) compared to non-smoking adults (8.2 microg/g creatinine). On a creatinine basis young children had slightly lower naphthol levels in urine compared with adults (7.5 microg/g creatinine). Preliminary reference values for the sum of 1- and 2- naphthol in urine as means of the 95th percentile are proposed: 41.2 microg/g creatinine (non-smoking adults) and 23.5 microg/g creatinine (young children). It is concluded that 1- and 2-naphthol levels in urine are suitable for human biomonitoring of the naphthalene exposure in environmental medicine.

Adolescent↗
PubMedDate not supplied

Morphology of nasal lesions in F344/N rats following chronic inhalation exposure to naphthalene vapors.

Naphthalene (CAS No. 91-20-3) administered by inhalation at concentrations of 10, 30, or 60 ppm for 6 hours per day, 5 days per week for 105 weeks caused nonneoplastic and neoplastic effects in nasal respiratory and olfactory regions of male and female F344/N rats. Non-neoplastic nasal effects were characterized by an increase in the incidence and severity of a complex group of lesions, including atypical hyperplasia, atrophy, chronic inflammation, and hyaline degeneration of olfactory epithelium; hyperplasia, squamous metaplasia, hyaline degeneration, and goblet cell hyperplasia of the respiratory epithelium; and hyperplasia and squamous metaplasia of mucosal glands. Neoplastic effects were characterized by the induction of two types of rare primary nasal tumors, olfactory neuroblastomas and respiratory epithelial adenomas. The incidences of olfactory neuroblastomas in males at 0 ppm, 10 ppm, 30 ppm, and 60 ppm were, respectively, 0%, 0%, 8%, and 6%, whereas in females they were 0%, 4%, 6%, and 24%. The incidences of respiratory epithelial adenomas in males at 0 ppm, 10 ppm, 30 ppm, and 60 ppm were, respectively, 0%, 12%, 17%, and 31% and in females 0%, 0%, 8%, and 4%. The olfactory neuroblastomas and respiratory epithelial adenomas were considered carcinogenic effects related to naphthalene exposure based on their relatively high incidence in exposed rats, their absence in concurrent control rats and NTP historical controls, and their rare spontaneous occurrence in rats of any strain.

Adenoma↗
PubMed1986

Spectrophotometric determination of copper in environmental samples by solid-liquid extraction of its 9, 10-phenanthrenequinone monoximate complex into molten naphthalene.

A fairly selective and sensitive spectrophotometric method has been developed for determination of copper after extraction of its 9, 10-phenanthrenequinone monoximate complex into molten naphthalene in the pH range of 6.1-8.4. At room temperature, the solid naphthalene containing the metal complex is separated by filtration, dissolved in dimethylformamide (DMF) and the absorbance measured at 470 nm against the reagent blank. Beer's law is obeyed in the concentration range, 0.0-9.6 micrograms of copper in 10ml of DMF. The molar absorptivity and sensitivity are 6.30 X 10(4) 1 mol-1 cm-1 and 0.001 micrograms cm-2, respectively. The interference of various ions has been studied and the method has been applied for the determination of copper in various standard reference materials, beers, wines, human hair and environmental samples.

Copper↗
PubMed1977

Hepatic mixed-function oxidase activity in mice treated with methylated benzenes and methylated naphthalenes.

Eight methylated benzene and five methylated naphthalene compounds were injected ip into adult male mice daily for 3 days. On the fourth day livers from control and treated mice were compared with regard to weight, microsomal N- and O-demethylase activity, and various spectral characteristics of microsomal cytochrome P-450. Three methylated benzenes and one methylated naphthalene produced significant increases in liver weight/body weight ratios, O-demethylation of p-nitroanisole, N-demethylation of aminopyrene, or a combination of these.

Animals↗
PubMed1997

Experimental indication of a naphthalene-base molecular aggregate for the carrier of the 2175 angstroms interstellar extinction feature.

Experiments where the simple polycyclic aromatic hydrocarbon (PAH) naphthalene (C10H8) is subjected to the energetic environment of a plasma have resulted in the synthesis of a molecular aggregate that has ultraviolet spectral characteristics that suggest it provides insight into the nature of the carrier of the 2175 angstroms interstellar extinction feature and may be a laboratory analog. Ultraviolet, visible, infrared, and mass spectroscopy, along with gas chromatography, indicate that it is a molecular aggregate in which an aromatic double ring ("naphthalene") structural base serves as the electron "box" chromophore that gives rise to the envelope of the 2175 angstroms feature. This chromophore can also provide the peak of the feature or function as a mantle in concert with another peak provider such as graphite. The molecular base/chromophore manifests itself both as a structural component of an alkyl-aromatic polymer and as a substructure of hydrogenated PAH species. Its spectral and molecular characteristics are consistent with what is generally expected for a complex molecular aggregate that has a role as an interstellar constituent.

Astronomical Phenomena↗
PubMed2000

Tethered naphthalene diimide-based intercalators for DNA triplex stabilization.

The synthesis and triplex stabilizing properties of oligodeoxyribonucleotides functionalized at the 5'- and/or 3'-termini with a naphthalene diimide-based (NDI) intercalator is described. The NDI intercalator was prepared in a single step from the corresponding dianhydride and was attached to the 5'-terminus of an oligodeoxyribonucleotide following a reverse coupling procedure. The DMT protecting group was removed and the sequence phosphitylated to generate the phosphoramidite derivative on the 5'-terminus of the support-bound oligodeoxyribonucleotide. The NDI intercalator with a free hydroxyl was then added in the presence of tetrazole. Attachment of the NDI to the 3'-terminus relied upon a tethered amino group that could be functionalized first with the naphthalene dianhydride, which was subsequently converted to the diimide. Using both procedures, an oligonucleo-tide conjugate was prepared having the NDI intercalator at both the 5'- and 3'-termini. Thermal denaturation studies were used to determine the remarkable gain in stability for triplexes formed when the NDI-conjugated oligonucleotide was present as the third strand in the complex.

Base Sequence↗
PubMed1989

Naphthalene-induced hemolysis in a black female toddler deficient in glucose-6-phosphate dehydrogenase.

Hemolysis following accidental ingestion of naphthalene in black females deficient in glucose-6-phosphate dehydrogenase (G-6-PD) has not been previously reported. A 20-month-old black female is presented and the literature reviewed. Although G-6-PD deficiency is X-linked, health care providers must be aware that hemolysis may occur in females who are deficient in G-6-PD after exposure to naphthalene.

Anemia, Hemolytic↗
PubMed1993

Structure of 1,8-bis(hydroxymethyl)naphthalene.

1,8-Naphthalenedimethanol, C12H12O2, M(r) = 188.24, monoclinic, P2(1)/n, a = 8.549(4), b = 4.856(3), c = 22.604(4) A, beta = 94.24(3) degrees, V = 935.8(7) A 3, Z = 4, Dx = 1.34 g cm-3, lambda(Mo K alpha) = 0.71073 A, mu = 0.84 cm-1, F(000) = 400, T = 295 K, R = 0.042 for 1455 unique reflections having I > 3 sigma I. In the title structure the exterior angles at ring atoms C(1), C(8) and C(9) deviate significantly from 120 degrees as a result of the steric interactions of the hydroxymethyl substituents. The ten C atoms comprising the naphthalene core have an average deviation of 0.012 (7) A from the best least-squares plane describing the core. The conformation of the title compound is compared to those of other 1,8-disubstituted naphthalenes. Each hydroxy group is involved in hydrogen bonding as both acceptor and donor, creating infinite chains that propagate in the [010] directions. The neutron-adjusted parameters for the two H...O(acceptor) distances are 1.78 (3) and 1.80 (3) A and for the two O--H...O(acceptor) angles are 165 (2) and 170 (2) degrees. The packing arrangement can be described as a modified herringbone structure with the shortest crystallographic axis coinciding with the b axis of the standard monoclinic setting.

Molecular Structure↗
PubMed1999

Dipotassium naphthalene-1,8-dicarboxylate-potassium bicarbonate.

The title substance, tripotassium naphthalene-1,8-dicarboxylate bicarbonate, 3K+.C12H6O4(2-).HCO3-, crystallized in the centrosymmetric space group Pbca. There is a single hydrogen bond. In it, the O and H atoms are ordered and OD...OA is 2.651 (3) A. There is a single significant intermolecular C-H...O interaction, with C...OA = 3.480 (5) A. Each potassium ion is coordinated by an irregular polyhedron of O atoms. These three polyhedra contain eight, eight and five members; each O atom is a member of at least two polyhedra. Structural comparisons are made with tetrapotassium naphthalene-1,4,5,8-tetracarboxylate hexahydrate.

Crystallography, X-Ray↗
PubMed1957

Antimalarial activity of hydroxy-substituted naphthalene compounds.

A new series of mono- and di-hydroxy substituted naphthalene compounds was synthesized and found to possess antimalarial activity against P. gallinaceum infection of young chicks. A representative compound with a high degree of activity was chosen for extensive testing against other malarial species and for pharmacological investigation. The formula of this compound, number 377C54, was 1:6-dihydroxy-2:5-bis(cyclohexylaminomethyl)naphthalene dihydrochloride. Effective doses against P. gallinaceum in chicks, P. berghei in mice and P. cathemerium in canaries were 2.3, 4.0, and about 6 mg./kg. respectively. Compound 377C54 acted rapidly against the parasitaemia of P. gallinaceum in chicks and P. knowlesi in a rhesus monkey. Parasiticidal activity remained in the blood of chicks for a long time after a single oral dose. The drug can be estimated by the production of colour on coupling with diazotized p-nitroaniline. Drug concentrations in blood from chicks and humans rose rapidly after oral administration. In tissues from chicks, particularly liver and lung, the drug persisted for a long period. An unsuccessful attempt was made to induce resistance to 377C54 in a strain of P. gallinaceum. Extensive pharmacological investigation showed that 377C54 possessed no special pharmacological properties.

Administration, Oral↗
PubMed2002

Interaction of NahR, a LysR-type transcriptional regulator, with the alpha subunit of RNA polymerase in the naphthalene degrading bacterium, Pseudomonas putida NCIB 9816-4.

NahR, a LysR-type transcriptional regulator, is required for expression of naphthalene catabolic operons. However, detailed mechanisms of transcriptional activation by NahR are poorly understood. Many transcriptional activators make direct contact with RNA polymerase (RNAP) to initiate transcription. We investigated the hypothesis that direct contact between NahR and the alpha subunit of RNAP (alphaRNAP) may be involved in expression of the naphthalene catabolic operons in Pseudomonas putida NCIB 9816-4. Interactions between the NahR and alphaRNAP in P. putida NCIB 9816-4 were analyzed using the yeast two-hybrid system. The results obtained indicate that protein-protein interactions occur between alphaRNAP and the NahR. Gene activation by NahR is consistent with the general transcriptional mechanism of class I transcription factors, which function by contacting alphaRNAP.

Amino Acid Sequence↗
PubMed1997

Differential inhibitory effects of melatonin analogs and three naphthalenic ligands on 2-[125I]iodomelatonin binding to chicken tissues.

We have compared the 50% inhibition values of 2-[125I]iodomelatonin ([125I]Mel) competition curves by melatonin and 3 naphthalenic ligands, N-[2-(7-methoxy-1-naphthyl) ethyl] cyclobutane carboxamide (S20642), N-propyl N-[2-(7-methoxy-1-naphtyl) ethyl] urea (S20753), and N-[2-(7-methoxy-1-naphthyl) ethyl] crotonamide (S20750), using membrane preparations of four tissues (lung, spleen, brain, and kidney) of the chicken simultaneously. In retired breeders, we have demonstrated that the affinities of S20642 were similar in the lung and spleen. However they were 2-fold lower in the brain and 80-fold lower in the kidney. Similar differential binding affinities to the melatonin receptors were observed in the four tissues of young male chicks. This suggests that age and sex have little influence on the differential inhibitory properties of melatonin and S20642 in the tissues studied. The addition of guanosine 5'-O-thiotriphosphate (GTPgammaS), which encouraged the uncoupling of melatonin receptor to the G protein complex, lowered the binding affinity of melatonin and S20642 in the tissues studied but their differential affinities in the four tissues were however maintained. The affinities of 5-methoxy-N-cyclopropanoyltryptamine (CPMT) in the kidney were also 5-10-fold lower than those in the lung, spleen, and brain of young male chicks. The distinctive differential affinities of melatonin, S20642, and CPMT for [125I]Mel binding sites in the chicken lung, spleen, brain, and kidney indicated that the binding sites in these tissues are heterogeneous. Our study implicated that the naphthalenic ligand S20642 may be a useful melatonin analog to distinguish melatonin receptor subtypes in tissues and a possible drug candidate worthwhile for further investigations.

Aging↗
PubMed2003

Crystal structure of naphthalene dioxygenase: side-on binding of dioxygen to iron.

Binding of oxygen to iron is exploited in several biological and chemical processes. Although computational and spectroscopic results have suggested side-on binding, only end-on binding of oxygen to iron has been observed in crystal structures. We have determined structures of naphthalene dioxygenase that show a molecular oxygen species bound to the mononuclear iron in a side-on fashion. In a complex with substrate and dioxygen, the dioxygen molecule is lined up for an attack on the double bond of the aromatic substrate. The structures reported here provide the basis for a reaction mechanism and for the high stereospecificity of the reaction catalyzed by naphthalene dioxygenase.

Binding Sites↗
PubMed2006

Novel intermediates of acenaphthylene degradation by Rhizobium sp. strain CU-A1: evidence for naphthalene-1,8-dicarboxylic acid metabolism.

The acenaphthylene-degrading bacterium Rhizobium sp. strain CU-A1 was isolated from petroleum-contaminated soil in Thailand. This strain was able to degrade 600 mg/liter acenaphthylene completely within three days. To elucidate the pathway for degradation of acenaphthylene, strain CU-A1 was mutagenized by transposon Tn5 in order to obtain mutant strains deficient in acenaphthylene degradation. Metabolites produced from Tn5-induced mutant strains B1, B5, and A53 were purified by thin-layer chromatography and silica gel column chromatography and characterized by mass spectrometry. The results suggested that this strain cleaved the fused five-membered ring of acenaphthylene to form naphthalene-1,8-dicarboxylic acid via acenaphthenequinone. One carboxyl group of naphthalene-1,8-dicarboxylic acid was removed to form 1-naphthoic acid which was transformed into salicylic acid before metabolization to gentisic acid. This work is the first report of complete acenaphthylene degradation by a bacterial strain.

Acenaphthenes↗