Search

Four cocrystals containing N′‐(butan‐2‐ylidene)pyridine‐4‐carbohydrazide (izbt) and one cocrystal containing N′‐isopropylideneisonicotinohydrazide (izact) were synthesized by reacting isoniazid with either butan‐2‐one (for the former) or acetone (for the latter). The coformers used to synthesize the izbt cocrystals were 2,4‐dihydroxybenzoic acid, 2,5‐dihydroxybenzoic acid, 2‐chloro‐4‐nitrobenzoic acid and 1‐naphthoic acid. 1‐Naphthoic acid was also used with izact to form a cocrystal. The 1:1 cocrystals are: N′‐(butan‐2‐ylidene)pyridine‐4‐carbohydrazide–1‐naphthoic acid (izbt–1nta), C10H13N3O·C11H8O2, N′‐(butan‐2‐ylidene)pyridine‐4‐carbohydrazide–2,4‐dihydroxybenzoic acid (izbt–2,4‐dhba), C10H13N3O·C7H6O4, N′‐(propan‐2‐ylidene)pyridine‐4‐carbohydrazide–1‐naphthoic acid (izact–1nta), C9H11N3O·C11H8O2, N′‐(butan‐2‐ylidene)pyridine‐4‐carbohydrazide–2‐chloro‐4‐nitrobenzoic acid (izbt–2c4n), C10H13N3O·C7H4ClNO4, and N′‐(butan‐2‐ylidene)pyridine‐4‐carbohydrazide–2,5‐dihydroxybenzoic acid (izbt–2,5‐dhba), C10H13N3O·C7H6O4. The cocrystals containing izbt were compared to those containing the same (or similar) coformers with izact that have been reported either here or in the Cambridge Structural Database (CSD). Most of the cocrystals showed different packing despite having the same hydrogen‐bonding motifs. The cocrystals were characterized by single‐crystal X‐ray diffraction (SC‐XRD), powder X‐ray diffraction (PXRD) and differential scanning calorimetry (DSC). [ABSTRACT FROM AUTHOR]

• 11 latent organocatalysts for one-component polyurethane adhesives. • Adhesives were tested in preparing a model of decorative facade insulation. • Low-scale validation method for stability assessment using a fan. • A picture taken of the adhesive allows for the stability measurement. • The adhesives have great potential in polyurethane industry. We focused on developing polyurethane (PU) adhesives with superior ambient thermal and hydrolytic stability, a crucial factor for industrial productivity. Our approach involved creating PU prepolymers that can withstand varying temperatures in ambient conditions. These prepolymers consist of conventional isocyanate-terminated polyurethane and metal-free acid:base organic catalysts, with the stability of the adhesive relying on the organocatalyst employed. We tested a series of 11 latent organocatalysts derived from the reaction between 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) and various acids. Among these, the catalyst based on 1-naphthoic acid exhibited exceptional stability, lasting at least 3 h at 60 °C and an average relative humidity of 65% under vigorous stirring. We assessed this stability using a fan-based stirrer and analyzed the curing conditions kinetically through DSC. Furthermore, our adhesive formulation is environmentally friendly as it is free of metals, specifically tin (typically present in catalysts such as dibutyltin dilaurate). This quality enhances its sustainability. To validate the practical applicability of the adhesives, we conducted tests using decorative facade models composed of siliciclastic sandstone extracted from a quarry in Vilviestre del Pinar (Burgos, Spain. Latitude: 41.951024° N, longitude: 3.078283° W) and extruded polystyrene (XPS). The results demonstrated the excellent hydrolytic and thermal stability of the adhesives, highlighting their significant potential for panel manufacturing in this context. [ABSTRACT FROM AUTHOR]

Abstract: As part of ongoing research to investigate structural requirements for lactate dehydrogenase inhibition by highly substituted naphthoic and indenoic acids, certain naphthalene and indene precursors to those types of compounds are required. Described here are efficient preparations of 1-naphthoic acid precursors 6-benzyl-2,3-dimethoxy-1-propylnaphthalenes, including compounds with substituted benzyl groups and 7-benzyl-2,3-dimethoxy-1-propylnaphthalene. Also described are the syntheses of indenoic acid precursors 2-benzyl-5,6-dimethoxy-7-propyl-1H-indenes, including compounds with substituted benzyl groups. These compounds were made from the key intermediates 6,7-dimethoxy-5-propyl-1-tetralone, 6,7-dimethoxy-8-propyl-1-tetralone, and 5,6-dimethoxy-4-propyl-1-indanone. [Copyright &y& Elsevier]

Abstract: Advanced glycation end-products, namely AGEs, are involved in the pathogenesis of numerous diseases. If AGEs inhibitors are well-known, only few products are described as compounds able to destroy those deleterious products. In this work, we describe naphthoic acid derivatives, particularly 1-(naphthalen-1-yl)propane-1,2-dione 9, allowing the simple and rapid detection of AGEs breakers using a 96-well microplate fluorescence assay. Since the inaugurate publication about AGEs breakers whose activity was demonstrated using HPLC analysis, this work proposes the first assay suitable for automated and high throughput screening of AGEs breakers. [Copyright &y& Elsevier]

Polycyclic aromatic hydrocarbons ( PAH) are widespread in methane-rich subsurface environments, such as oil reservoirs and fuel-contaminated aquifers; however, little is known about the biodegradation of these compounds under methanogenic conditions. To assess the metabolism of PAH in the absence of electron acceptors, a crude oil-degrading methanogenic enrichment culture was tested for the ability to biodegrade naphthalene, 1-methylnaphthalene (1- MN), 2-methylnaphthalene (2- MN), and 2, 6-dimethylnaphthalene (2, 6-di MN). When methane was measured as an indicator of metabolism, nearly 400 μmol of methane was produced in the 2- MN- and 2, 6-di MN-amended cultures relative to substrate-unamended controls, which is close to the amount of methane stoichiometrically predicted based on the amount of substrate added (51-56 μmol). In contrast, no substantial methane was produced in the naphthalene- and 1- MN-amended enrichments. In time course experiments, metabolite analysis of enrichments containing 2- MN and 2, 6-di MN revealed the formation of 2-naphthoic acid and 6-methyl-2-naphthoic acid, respectively. Microbial community analysis by 454 pyrosequencing revealed that these PAH-utilizing enrichments were dominated by archaeal members most closely affiliated with Methanosaeta and Methanoculleus species and bacterial members most closely related to the Clostridiaceae, suggesting that these organisms play an important role in the methanogenic metabolism of the substituted naphthalenes in these cultures. [ABSTRACT FROM AUTHOR]

The article presents a study which investigates the activity of CYP199A2 when associated with three hydroxynaphthoic acids. The study uses a synthetic method on dihydroxynaphthoic acids with the use of CYP199A2 as an oxidation biocatalyst. The study also investigates the use of the enzyme in the synthesis of dihydroxynaphthoic acids. Results show that CYP199A2 exhibits an oxidation activity which effectively catalyzed the regioselective oxidation of various dihydroxynaphthoic acids.

Abstract: The Fourier transform infrared gas phase spectrum of Naphthoic acid (NA) was recorded in the region 4000–400cm−1. The Fourier transform Raman spectrum and Fourier transform IR spectra of NA were recorded in solid phase. Quantum chemical calculations of energies, geometrical structure, infrared intensities, Raman scattering activities and vibrational wavenumbers of NA in ground state have been carried out by density functional (DFT/B3LYP) and BLYP method with 6-31G(d,p) as basis set. A good correlation was found between the computed and experimental wavenumbers. A detailed interpretation of the infrared and Raman spectra of NA was also reported. The dimer parameters (intermolecular hydrogen bonding) by B3LYP/6-31G(d,p) method are also calculated. The polarizability and Mullikan atomic charges have also been computed using ab inito HF and DFT calculations. Comparison of simulated spectra provides important information about the ability of the computational method to describe the vibrational modes. [Copyright &y& Elsevier]

Two new compounds were isolated from the whole plant of Helichrysum arenarium (L.) Moench. By means of spectroscopic data (IR, UV, 1D and 2D NMR, HR-MS, ESI-MS, and NOESY) and chemical evidence, the structures were established as 6,7-dimethoxy-4-hydroxy-1-naphthoic acid (1) and (Z)-5-hydroxy-7-methoxy-4-[3-methyl-4-(O-β-d-xylopyranosyl)but-2-enyl]isobenzofuran-1(3H)-one (2). [ABSTRACT FROM AUTHOR]

Abstract: Starting from the known FXR agonist GW 4064 1a, a series of stilbene replacements were prepared. The 6-substituted 1-naphthoic acid 1b was an equipotent FXR agonist with improved developability parameters relative to 1a. Analog 1b also reduced the severity of cholestasis in the ANIT acute cholestatic rat model. [Copyright &y& Elsevier]

Polycyclic aromatic hydrocarbons (PAHs) are widespread persistent pollutants that readily undergo biotic and abiotic conversion to numerous transformation products in rivers, lakes and estuarine sediments. Here we characterize the developmental toxicity of four PAH transformation products each structural isomers of hydroxynaphthoic acid: 1H2NA, 2H1NA, 2H3NA, and 6H2NA. Medaka fish (Oryzias latipes) embryos and eleutheroembryos were used to determine toxicity. A 96-well micro-plate format was used to establish a robust, statistically significant platform for assessment of early life stages. Individual naphthoic acid isomers demonstrated a rank order of toxicity with 1H2NA>2H1NA>2H3NA>6H2NA being more toxic. Abnormalities of circulatory system were most pronounced including pericardial edema and tube heart. To determine if HNA isomers were AhR ligands, spatial-temporal expression and activity of CYP1A was measured via in vivo EROD assessments. qPCR measurement of CYP1A induction proved different between isomers dosed at respective concentrations affecting 50% of exposed individuals (EC50s). In vitro, all ANH isomers transactivated mouse AhR using a medaka CYP1A promoter specific reporter assay. Circulatory abnormalities followed P450 induction and response was consistent with PAH toxicity. A 96-well micro-plates proved suitable as exposure chambers and provided statistically sound evaluations as well as efficient toxicity screens. Our results demonstrate the use of medaka embryos for toxicity analysis thereby achieving REACH objectives for the reduction of adult animal testing in toxicity evaluations. [Copyright &y& Elsevier]

Abstract: Three different series of xylosylated naphthoic acid–amino acid conjugates containing one or two amino acid residues were synthesized for the investigation of glycosaminoglycan priming and potential use as anti-tumor drugs. All xylosylated naphthoic acid-conjugates inhibited the growth of normal lung fibroblasts to some extent, whereas the growth of tumor derived T24 carcinoma cells was not affected. There was no correlation between amino acid conjugation, retention time and the antiproliferative activity. Only one compound initiated the priming of glycosaminoglycans. Modification of the naphthalene ring with one or two amino acid residues did not have any effect on proteoglycan biosynthesis or glycosaminoglycan priming in T24 carcinoma cells. [Copyright &y& Elsevier]

Abstract: A simple and efficient chemoselective alkylation of phenols in polyfunctional aromatic compounds with different alkyl halides in the presence of K2CO3/TBAB is reported. The method is successful with various hydroxy aromatic acids or oximes possessing other functional groups. [Copyright &y& Elsevier]

Abstract: Naphthenic acid (NA) has been recognized as one of the major sources of corrosion in oil production and refining. In this study, catalytic decarboxylation of carboxylic acid model compounds and naphthenic acid removal from crude oil were investigated. A metal oxide catalyst, MgO has been developed and its effectiveness in catalyzing decarboxylation reactions involving carboxylic acid compounds such as naphthoic acid has been determined based on the formation of CO2 and the conversion of acid. The major reaction takes place in the temperature range of 150–300°C. The role of MgO in the system is considered to be multiple. It has the ability to adsorb acidic compounds via acid–base neutralization and it can also promote reactions such as decarboxylation and hydrocarbon cracking at the increased temperature. Direct application of MgO to crude oil results in significant naphthenic acid removal and lower total acidity of the oil as evidenced by a decrease in RCntration as determined by FT-IR and a lower total acid number (TAN). [Copyright &y& Elsevier]

Abstract: The sorption of 16 ionizable organic compounds (IOCs) to an estuarine sediment was measured in synthetic estuarine water as a function of IOC concentration (1–100 μM) at fixed ionic strength (0.4 M), pH (7.6), and sediment concentration (0.018 g sediment kg−1 suspension). Of the 16 IOCs, 11 were naphthoic acids and five were quinoline compounds. The linear sorption distribution coefficient (K d) was used to correlate sorption to IOC physicochemical and molecular characteristics. With respect to naphthoic acid, sorption increased with the addition of ortho-substituent groups and with increasing chain length of the 1-acid group, and the greatest increase occurred with ortho-hydroxyl, carbonyl, and carboxyl groups. With respect to quinoline, sorption decreased with substituent group addition (except for nitro group) and with additional heterocyclic N atoms. For the naphthoic acids, log K d exhibited a positive correlation with water solubility (log S w) indicative of sorption primarily to mineral surfaces under the solution chemistry. For the quinoline compounds, log K d exhibited a negative correlation with log S w and a positive correlation with n-octanol/water partition coefficient (log K OW) indicative of sorption primarily to organic matter. For both compounds, poor or no correlations were established between log K d and acid dissociation constant (pK a1), and between log K d and a variety of molecular connectivity indexes. The results from this study demonstrate that the sorption of IOCs differ depending on their backbone structure and may differ between parent compound and ionizable degradation product. [Copyright &y& Elsevier]

The ability of a plant cytochrome P450 to bind and metabolise plant endogenous molecules and xenobiotics was investigated. The work was performed on the yeast-expressed CYP73A1, a cinnamate 4-hydroxylase isolated from Helianthus tuberosus. CYP73 controls the general phenylpropanoid pathway and is likely to be one of the most abundant sources of P450 in the biosphere. The enzyme shows a high selectivity toward plant secondary metabolites. Nevertheless, it oxygenates several small and planar xenobiotics with low efficiency, including an herbicide (chlorotoluron). One xenobiotic molecule, 2naphthoic acid, is hydroxylated with an efficiency comparable to that of the physiological substrate. This reaction was used to devise a fluorimetric test for the rapid measurement of enzyme activity. A series of herbicidal molecules (hydroxybenzonitriles) are shown to bind the active site without being metabolised. These molecules behave as strong competitive inhibitors of CYP73 with a Ki in the same micromolar range as the Km for the physiological substrate. It is proposed that their inhibition of the phenylpropanoid pathway reinforces their other phytotoxic effects at the level of the chloroplasts. All our results indicate a strong reciprocal interaction between plant P450s and xenobiotics. [ABSTRACT FROM AUTHOR]

The present work studies the UV–Vis spectroscopic properties of 6-bromo-2-naphthoic acid (BNA) dissolved in methanol, tetrahydrofuran (THF) and ethyl acetate. It has been found that there are significant differences between the emission spectra for the samples with different concentrations of BNA in methanol. Also, the analogical changes have been observed in the case of the samples of BNA in THF and ethyl acetate which have been studied immediately after preparation and 24 h after preparation. It could be explained by deprotonation processes that take place in BNA. Moreover, it has been found that the anion formation process in BNA is more intensive in the case of methanol solvent in comparison with the cases of THF and ethyl acetate. This fact could be explained by the different polarity of these solvents. As methanol is characterized by higher polarity, the deprotonation is more intensive in the case of this solvent. To verify our assumption the quantum-chemical calculations have been also performed. It has been found that the enthalpy of dissociation (the bond-dissociation energy) is equal to 183.2, 200.2 and 205.4 kcal/mol for BNA dissolved in methanol, THF and ethyl acetate, respectively. It explains why the deprotonation process in methanol is more intensive than in THF and ethyl acetate. Thereby, the study shows that the obtained theoretical calculations are in good agreement with the experimental results. Unlabelled Image • 6-Bromo-2-naphthoic acid dissolved in methanol, THF and ethyl acetate has been studied. • The ionic and neutral species of 6-bromo-2-naphthoic acid are observed in its solution. • The considerable differences in photophysical properties for both species have been found. • Results of quantum chemical calculations also have been reported. • HOMO and LUMO orbitals have been presented. [ABSTRACT FROM AUTHOR]

A 6-step synthesis of the naphthoic acid component of the natural antitumor agent neocarzinostatin chromophore is described. The synthetic route employs a 4-bromo-3-methylanisole as the starting material, proceeds in 31-37% yield for the 6 steps, and features as the key step a photocyclization reaction that is an interesting variant of known photocyclization reactions of stilbenes and phenylbutadienes., Chemistry and Chemical Biology