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The discovery of a concise route enabling site-selective arylation of polycyclic aromatic hydrocarbons (PAHs) with easily available aryl sources is an appealing yet challenging task toward the bottom-up preparation of π-extended PAHs. Disclosed herein is a palladium-catalyzed C8–H arylation of 1-naphthoic acid derivatives with aryl iodides in a low reactant molar ratio via an electrophilic aromatic substitution (SEAr) process. In addition, a C8–H annulation protocol is developed to rapidly assemble benzanthrones by simply switching the solvent to 1,1,1,3,3,3-hexafluoropropan-2-ol (HFIP).

(2E)-3-(2-Bromo-6-hydroxy-4-methoxyphenyl)-1-(naphthalene-2-yl)prop-2-en-1-one (d1) was synthesized by the Claisen-Schmidt condensation method and characterized by 1H NMR, 13C NMR spectral studies. The anti-inflammatory activity was conducted in Swiss albino rats for paw edema model. Edema was actuated with 1 % carrageenan to every one of the animals following 1 h of the oral medicines. Paw thickness was checked at t = 1, 2, 3, 4, 5 and 24 h. Stair climbing score and motility score were surveyed at t = 24 h. Compound d1 signicant decline in paw thickness at p < 0.001 diminished by 32 % in paw thickness. The compound d1 signicantly expanded the stair climbing and motility score. This study suggested that the compound d1 exhibits remarkable anti-inflammatory activity when compared with that of the standard drug.

A novel heterocyclic compound, 1-(4-methoxy phenyl)-2-((5-(1-(naphthalen-1-yloxy) ethyl) -[1,3,4]-oxadiazol-2-yl) sulfanyl) ethanone was synthesized using standard method and chemical structure of the synthesized compound was identified using FTIR spectrum. Needle shaped single crystals have been grown using solution growth technique. The grown crystals were characterized using single crystal XRD, UV-visible and Thermal analysis. The crystal structure study shows that the compound crystallizes in Monoclinic crystal system with a space group of P21/a and cell parameters are determined. UV-Visible study shows that the crystal is transparent in the entire visible region. The thermal stability of the material was determined by TG and DTA analysis.

A new type of catalytic stereoselective cascade pseudo four-component reaction was discovered. The simple and facile pseudo four-component reaction of isatins, cyclic ketones with two molecules of malononitrile catalyzed by triethylamine at ambient temperature stereoselectively results in the formation of tetracyclic spirooxindoles in 60–90% yields. Thus, a new simple and efficient ‘one-pot’ method to synthesize substituted spirooxindoles was found directly from reasonable starting compounds. Unique stereoselectivety was achieved on two or three centers in this pseudo four-component reaction.

Isocyanides, dialkyl acetylenedicarboxylates, and 2,3-dichloronaphthalene-1,4-dione react in multicomponent reaction to produce novel dispiro[furan-2,1′-naphthalene-4′,2″-furan]tetracarboxylates in excellent yields at room temperature.

A spectrophotometric method has been developed for the determination of Cu(II) using 2-Hydroxy-1-Naphthalene carboxaldehyde phenyl hydrazone as an extractive reagent. The reagent forms a coloured complex, which has been quantitatively extracted into n-butanol at pH 9.2. The method obeys Beer’s law over arrange from 1 to 10 ppm. The Molar absorptivity and Sandell’s sensitivity were 0.97 × 104 L mol-1cm-1 and 0.26 µg·cm-2 respectively. The proposed method is very sensitive and selective. The method has been successfully applied to synthetic and commercial samples.

A new type of catalytic stereoselective cascade pseudo four-component reaction was discovered. The simple and facile pseudo four-component reaction of isatins, cyclic ketones with two molecules of malononitrile catalyzed by triethylamine at ambient temperature stereoselectively results in the formation of tetracyclic spirooxindoles in 60–90% yields. Thus, a new simple and efficient ‘one-pot’ method to synthesize substituted spirooxindoles was found directly from reasonable starting compounds. Unique stereoselectivety was achieved on two or three centers in this pseudo four-component reaction.

Isocyanides, dialkyl acetylenedicarboxylates, and 2,3-dichloronaphthalene-1,4-dione react in multicomponent reaction to produce novel dispiro[furan-2,1′-naphthalene-4′,2″-furan]tetracarboxylates in excellent yields at room temperature.

The adsorption and photochemical reaction of naphthalene vapor at the air-water interface of water films (22 microm and 450 microm) were studied in a horizontal flow reactor. Experiments were conducted in the regime where gas-phase mass transfer resistance did not limit the uptake. The equilibrium uptake was dependent on water film thickness only below 1 microm. Bulk water-air and air-to-interface partition constants were estimated from the experiments. The equilibrium partition constant between the water film and air decreased with increasing temperature. Photochemical reaction products were isolated in the water film after exposure to UV light. Four main oxygenated products were identified (1,3-indandione, 1(3H)-isobenzofuranone (phthalide), 2H-1-benzopyran-2-one (coumarin), and 1-naphthol). The initial rates of product formation were 46 to 154% larger for the thin film (22 microm) compared to both a thick film (450 microm) and bulk aqueous phase photooxidation. The atmospheric implications of reactions in water films are discussed.

Ozone oxidation kinetics of 1-naphthalene (1NS), 1,5-naphthalene (1,5NDS), and 3-nitrobenzene (3NBS) sulphonic acid is reported here. The contribution of indirect free-radical pathways and direct ozone reactions are accounted for in the proposed model. Second order kinetic constants of direct reactions were estimated at around 252 (M -1 s -1 ), 41 (M -1 s -1 ) and 22 (M -1 s -1 ), for INS, 1,5NDS, and 3NBS sulphonic acids, respectively. At pH 3, the indirect reaction accounted for 2 %, 15 % and 4 % of total primary oxidation of 1NS, 1,5NBS, and 3NBS sulphonic acids, respectively. At pH 9, indirect reaction contribution increased to 73 %, 84 % and 48 %, respectively. C4 compounds (maleic and fumaric acids), C2 (oxalic), C1 (formic) and sulphate were identified as oxidation by-products in all cases. TOC slowly decreased throughout ozonation, reaching around 40-60% and 60-70% reduction over 90 min. at pH 7 and 3, respectively.

This paper describes the ozone oxidation kinetics of 1-naphthalene (1NS), 1,5-naphthalene (1,5NDS), and 3-nitrobenzene (3NBS) sulphonic acid. The presence of hydroxyl radicals and their effect on the overall rate of reaction was studied. Second order kinetic constants of direct reactions were estimated at around 252 M-1s-1, 41 M-1s-1 and 22 M-1s-1, for 1NS, 1,5NDS, and 3NBS sulphonic acids, respectively. At pH 3, the indirect reaction accounted for 2%, 15% and 4% of total primary oxidation of 1NS, 1,5NBS, and 3NBS sulphonic acids, respectively. At pH 9, indirect reaction contribution increased to 73%, 84% and 48%, respectively. C4 compounds (maleic and fumaric acids), C2 (oxalic), C1 (formic) and sulphate were identified as oxidation by-products in all cases. TOC slowly decreased throughout ozonation, reaching around 40-60% and 60-70% reduction over 90 minutes at pH 7 and 3, respectively.

Des essais sur le terrain ont ete effectues durant deux saisons successives a la station de recherches de la faculte d'agronomie de l'universite du Caire a Guizeh, en Egypte sur le cultivar de coton egyptien Guizeh 75 (Gossypium barbadense L.). Les cotonniers recurent des pulverisations d'un regulateur de croissance (acide 1-naphtalene-acetique) soit une seule fois 90 jours juste apres le semis soit deux fois (90 et 105 jours apres la date de semis) soit trois fois (90-105 et 120 jours apres le semis durant l'etape de la formation des capsules). Des concentrations de 5, 10, 15, 20 et 25 ppm furent utilisees. Les plantes temoins furent pulverisees par de l'eau pure. Une etude fut entreprise concernant l'effet des traitements mentionnes sur les composantes du rendement du coton et les proprietes des fibres. L'application de l'acide 1-naphtalene-acetique, a augmente le nombre de capsules ouvertes par plant, la masse moyenne des capsules, la masse de graines, le rendement en coton-graine et en fibres, par plante et par hectare. Les effets les plus marques furent obtenus en utilisant les concentrations 15 et 20 ppm, a condition d'appliquer chaque concentration deux fois. Le pourcentage de fibres, les parametres de longueur des fibres et la valeur du micronaire n'ont pas ete affectes significativement par l'acide 1-naphtalene-acetique. La solidite du faisceau fut affectee par l'acide mais sans qu'aucune tendance stable ne puisse etre degagee. L'usage de deux ou trois traitements a donne les meilleurs resultats concernant les composantes du rendement et le rendement final du coton, en comparaison avec une seule application. Les resultats de cette etude suggerent que 20 ppm d'acide 1-naphtalene-acetique appliques deux fois sur les cotonniers egyptiens ameliorent la production.

Recently, plant growth regulators have been used for multiple purposes in tree fruits. NAA (1-naphthalene acetic acid) and AVG (aminoethoxyvinylglycine) have been widely used in apple fruit. NAA and AVG have been used to control preharvest fruit drop and improve the quality of fruit. In this study, the effects NAA (20 mgL–1), AVG (500 mgL–1) and control (non treatment) treatments on physical, chemical, colour characteristics and mechanical properties of apple (cv. Braeburn) were investigated. The higher length, width, thickness, geometric mean diameter, fruit mass, surface area, projected area, volume, fruit and bulk densities were obtained in AVG treatment. Total acidity, total soluble solid content and starch starch index were higher in control as compared to NAA and AVG treatments. Total phenolic content of the flesh apple was higher than the other treatments. While total antioxidant activities of skin and flesh fruit were higher in AVG according to FRAP method, total monomeric anthocyanin was lower in AVG as compared to the other treatments. AVG treatment generally had positive impacts on fruit removal force, skin and flesh firmnesses because retarding the fruit ripening.

The solvatochromic fluorescence properties of 8-(phenylamino)-1-naphthalene-ammoniumsulfonate (1) were investigated in 22 pure solvents of rising polarity. The measurements of both Stokes' shifts and intensities discriminated between protic and aprotic solvents. Fairly good linear correlation plots of the dependence could be obtained on neglection of the values of tert.-butanol, DMF and DMSO.

In this work the effects of silver ion, 1-Naphthalene acetic acid (NAA) and 6-Benzylaminopurine (BAP) and their interactions on micropropagation of Populus alba cl. LBM, male genotype with fastigiate tree shape were studied. Three concentrations of silver nitrate [(Ag NO3), (0, 1.0 and 2.0 mu M)], two concentrations of NAA (0 and 0.1 mu M) and three concentrations of BAP (0, 0.5 and 2 mu M) were added to solidified Aspen culture (AC) media containing 2.0 mu M of kinetin and 10 g L-1 sucrose. Three traits were examined: percentage rooting, percentage microshoots with new shoots and the ratio of shoot length increment within the first and fourth week and length after the first week. The results showed a significant effect of NAA concentration on all the examined traits. The main effects of all examined factors and the interaction between different concentrations of three growth regulators had a significant effect on rooting and multiplication percentage. The inclusion of NAA in the medium at a concentration of 0.1 mu M stimulated multiplication and suppressed shoot growth and rooting, while BAP had the opposite effect. Silver ions stimulated both shoot multiplication and rooting, thus suggesting that it masked the effects of endogenous inhibitors such as ethylene.

C 16 H 17 ClO 6 cristallise dans P2 1 2 1 2 1 avec a=14.932, b=14.850, c=7.173A, Z=4; affinement jusqu'a R=0.0407. C 16 H 17 BrO 6 cristallise dans P2 1 2 1 2 1 avec a=15.054, b=14.924, c=7.207A, Z=4; affinement jusqu'a R=0.0431. C 16 H 17 IO 6 cristallise dans P2 1 2 1 2 1 avec a=15.317 b=15.056, c=7.255A, Z=4; affinement jusqu'a R=0.0587.

The crystal structure of the title compound, C12H10O2, was originally determined by Rajan [Acta Cryst. (1978). B34, 998–1000] using intensity data estimated from Weissenberg films. This redetermination provides a structure with significantly improved precision with respect to the geometric parameters. In the crystal structure, intermolecular O—H...O hydrogen bonds, weak C—H...O hydrogen bonds and C—H...π interactions link the molecules into a two-dimensional sheet lying parallel to (100).

Leucojum aestivum is a native, protected ornamental and medicinal plant in Hungary and in Ukraine too. The aim of our work was to establish in vitro cultures of this bulbous plant. Prior to surface sterilisation the old leaves and roots were dissected from the bulbs and they were stored in a refrigerator (2-3°C) for different periods (1 week for the first starting experiment and 5 weeks for the second one). After sterilisation, bulbs, bulb scales and leaves of the bulbs were placed on Murashige and Skoog's (1962) medium with 1 mg/1 benzyl-adenine (BA) and 0,1 mg/1 naphthalene acetic acid (NAA). At the first starting experiment 81,3%, and at the second one 92,3% of the explants turned to be sterile. Bulblets and roots were developed on the explants in the case of using bulb plates together with bulb scales and leaves as inoculua. The best result was achieved after 5 weeks chilling and it was possible to gain little bulbs from the bulb leaves too.

(Global Journal of Pure and Applied Sciences: 2002 9(1): 117-126)

The metabolism of 1-naphthalene acetic acid by the ectomycorrhizal fungus Pisolithus arhizus was investigated. The structures of the two major products of the transformation, 1,2-dihydroxy-1,2-dihydronaphthalene-1-acetic acid γ-lactone and 4-hydroxy-1-naphthalene acetic acid, were established by spectroscopic techniques, particularly 2D NMR.

The fluorescent probe 8-anilino-l-naphthalene sulphonic acid (ANS) has been evaluated as a histochemical stain for plant tissues. The wide specificity of the compound for hydrophobic binding sites limits its analytical use, but renders it of considerable value as a general fluorescent stain for use in epi-illumination fluorescence microscopy. Used in this way it is analogous to the light-microscope stain toluidine blue. ANS has also been found to be a sensitive vascular tracer.

The method of Weber, G. and Young, L. ((1964) J. Biol. Chem. 239, 1415–1423) allows one to evaluate by graphical means the maximum fluorescence intensity of a fixed amount of anilinoaphthalene sulphonate (ANS) in presence of increasing concentrations of proteic sites for this probe. This value is used to estimate the quantum yield of the fixed ANS. The method is based on the linear extrapolation of the double reciprocal plot of fluorescence intensity vs. protein concentration. We show by experimental means and critical analysis that such an extrapolation is not valid unless two specific conditions are fulfilled: the fractional saturation of the sites at the beginning of the titration must be low and the fractional fixation of the probe at the end of the titration must be high. Due to the low affinity of membranes for ANS, the latter condition is not easily satisfied, which may lead to erroneous interpretations. We propose a procedure which overcomes this drawback. When applied to microsomes of roots from horse bean, it reveals that the quantum yield of bound ANS is insensitive to pH in the pH range 2–8, and to the presence of Ca 2+ .

The effectiveness of 8-anilino-1-naphthalene sulphonic acid (ANS) in the radioimmunoassay (RIA) of thyroxine (T4) as an inhibitor of the binding of T4 to serum T4-binding proteins is assessed. The optimum ANS concentration is dependent upon the antiserum and the method used for separating free and bound T4. If T4 binding to serum proteins is not completely inhibited, resin separation methods may yield low values, while polyethylene glycol and double-antibody methods may produce high values for T4 concentration. Even with optimum ANS concentration gross errors in measurement of T4 may occur in patients with high thyroxine-binding globulin (TBG) concentrations.

Both the sialoglycoprotein of human erythrocyte membranes, glycophorin, and the sialic acid free protein, obtained by treatment of glycophorin with neuraminidase (EC 3.2.1.18), increase the fluorescence of 8-anilino-1-naphthalene sulfonate (ANS). Binding of ANS to glycophorin is weak compared with the binding to bovine serum albumin (BSA). Equilibrium dialysis gives an apparent binding constant of about 4 × 103 M−1 at neutral pH, but Ka increases 1.75 times when NaCl or CaCl2 are added and 10-fold when the pH is lowered to 3.0. Sialic acid groups do not significantly affect ANS binding, although they have some effect at low ionic strength and neutral pH.Fluorescence studies indicate only one to two binding sites for ANS, with apparent pK = 3.8 ± 0.2. and located close to aromatic residues in glycophorin.Polarization and quantum efficiency of the fluorescence of ANS associated with glycophorin fail to indicate changes in the vicinity of the binding site when the pH is lowered.

Some of the apparently anomalous findings made with the fluorescent probe 8-anilino-1-naphthalene sulfonic acid (ANS) have been reinvestigated using rat liver mitochondria. The results have been found compatible with current views on energy conservation.

Irradiation of the title compound (2) gave a wide range of products, identified as compounds (3)–(7) on the basis of spectroscopic data and chemical evidence, which result from β-cleavages and intramolecular cycloaddition.

We have determined that 8-anilino-1-naphthalene sulfonic acid (ANS) and ipodate are effective inhibitor in vitro of 125I-T3 binding to rat hepatic nuclei receptors. Both of these agents are estimated to have a Kd for the T3 receptor of about 1--2 x 10(-4) M. Indirect preliminary studies suggest that ANS is a non-competitive inhibitor and ipodate is a competitive inhibitor of T3 binding. Compounds such as tyropanoate and diatrizoate and iodide had no effect on T3 receptor binding. Further in vivo studies with ipodate suggested that T3 receptor binding inhibition also occurred when ipodate was given intravenously to rats.

Myosin prepared from tilapia (Serotherodon aureus) was complexed with 8-anilino-1-naphthalene sulfonate (ANS) and continuously heated at 1 degree C/min. A large increase in fluorescence was observed with a transition temperature of 34 degrees C. The effect of several salts on the transition temperature was tested. A plot based on the equation of E. E. Schrier and E. B. Schrier [(1967) J. Phys. Chem. 71, 1851-1860] gave a value of less than or equal to 500 cal/mol-deg for the change in enthalpy per residue due to exposure to solvent. The ratio of hydrophobic group to amide group exposure to solvent was intermediate compared with the ratio of RNase and gelatin. Fluorescence titrations yielded one high affinity site with a Kb of 2 X 10(6) M-1 and at least 200 low affinity sites with an average value of 1 X 10(5) M-1. The parameters did not change significantly with temperature. We propose that the increase in ANS fluorescence reflects changes in conformation of myosin as monitored by these low affinity sites, resulting in an increase in surface hydrophobicity and representing a small enthalpic change in the conformation of the myosin molecule. As a consequence, the change in conformation accelerates polymerization of myosin oligomers.

Platelet myosin light chain kinase is a calmodulin dependent enzyme which requires calmodulin for its activity and is intimately related to actomyosin contracting system. Platelet actomyosin contraction may cause the release reaction of platelet. N-(6-aminohexyl)-5-chloro-naphthalene sulfonamide (W-7) is one of the calmodulin interacting agents, and selectively inhibits calmodulin activity. Since platelet membrane phospholipases which are responsible for the release of arachidonic acid from membrane phospholipids may also be calmodulin-dependent enzymes, the inhibitory effects of W-7 on platelet function were examined. W-7 in a concentration as low as 10 7#x03BC;M inhibited platelet aggregation and release reaction induced by ADP, collagen, epinephrine, thrombin, arachidonic acid and Ca2+-ionophore A23187. When platelets were preincubated with W-7 before addition of an aggregating agent, the inhibition became more pronounced. In ADP-induced aggregation, only the second phase was inhibited. Arachidonate metabolites (PGG2/H2 and thromboxane A2) failed to induce aggregation and release reaction of platelets preincubated with W-7. Furthermore, release of arachidonic acid from platelet membrane phospholipids induced by A23187 in the presence of indomethacine was inhibited by W-7. W-7 had no effect on glucose metabolism in platelets. The c-AMP levels in platelets were not significantly changed by incubation with W-7. These results suggest that W-7 inhibits directly phospholipase A2 and/or phospholipase C in addition to myosin light chain kinase. These results may in turn indicate that calmodulin is involved in platelet aggregation and release reaction mechanism including membrane phospholipases and the target system of thromboxane A2 (possibly actomyosin contracting system).