• Journal of the Korean Chemical Society
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• v.51 no.2
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• pp.115-124
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• 2007

A series of α, β-unsaturated ketones are synthesized by Crossed - Aldol condensation reaction, from ecofriendly 6-methoxy-2-naphthyl ketones and substituted benzaldehydes under solvent free conditions using silica-sulfuric acid as a catalytic reagent. The yields of ketones are more than 90% and the catalyst was reusable for further run. There is no appreciable decrease in the yield of product and the activity of catalyst. These chalcones were characterized by their physical constants and spectral data (IR, 1H-, 13C-NMR and Mass). These spectral data are subjected to correlate various Hammett substituent constants with single and multiparameter correlation equations. From the results of statistical analysis the influence of electronic effects of substituents on the spectral data of the ketones were explained.

• Bulletin of the Korean Chemical Society
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• v.32 no.7
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• pp.2413-2417
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• 2011

The specific rates of solvolysis of 1- naphthyl chloroformate (1-NaphOCOCl, 1) and 2-naphthyl chloroformate (2-NaphOCOCl, 2) have been determined in a wide range of solvents at 2.0 and 10.0$^{\circ}C$. These give a satisfactory correlation over the full range of solvents when the extended (two-term) Grunwald-Winstein equation is applied. The sensitivities (l and m-values) to changes in solvent nucleophilicity ($N_T$) and solvent ionizing power ($Y_{Cl}$) are similar to those reported previously for solvolysis of phenyl chloroformate, which has been suggested to proceed through an addition-elimination mechanism with the addition step being rate determining. For four representative solvents, studies were made at several temperatures and activation parameters determined. These observations were also compared with those previously reported for phenyl chloroformates and naphthoyl chlorides.

• Polymer(Korea)
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• v.25 no.6
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• pp.796-802
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• 2001

Novel monomer for polybenzimidazole was prepared and polymerized via aromatic nucleophilic substitution reaction. Thus, N-(4-fluorobenzoyl)-4-methoxy-N'-naphthyl-1,2-phenylenediamine was synthesized from the reaction of 4-methoxy-N-naphthyl-1,2-phenylenediamine and 4-fluorobenzoyl chloride. N-(4-fluorobenzoyl)-4-methoxy-N'-naphthyl-1,2-phenylenediamine was converted to 2-(4-fluorobenzoyl)-5-hydroxy-1-naphthylbenzimidazole by ring closure and demethylation reaction. Polymerization was done in N-cyclohexyl-2-pyrrolidinone (CHP) containing potassium car bonate. The resulting polymer was soluble in N-methyl-2-pyrrolidinone (NMP) and had inherent viscosity of 0.38 dL/g (NMP at $30^{\circ}C$). The glass transition temperature ($T_g$ ) of the polybenzimidazole was $270^{\circ}C$. The thermogravimetric analysis (TGA) thermograms of this polymer showed 5% weight losses at $550^{\circ}C$ in nitrogen and at $540^{\circ}C$ in air.

• Rapid Communication in Photoscience
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• v.4 no.2
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• pp.37-40
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• 2015

To examine the photosensitized biomolecules damaging activity, dimethoxyP(V)tetrakis(2-naphthyl)porphyrin (NP) and dimethoxyP(V)tetraphenylporphyrin (PP) were synthesized. The naphthyl moiety of NP hardly deactivated the photoexcited P(V)porphyrin ring in ethanol. In aqueous solution, the naphthyl moiety showed the quenching effect on the photoexcited porphyrin ring, possibly through electron transfer and self-quenching by a molecular association. Binding interaction between human serum albumin (HSA), a water soluble protein, and these porphyrins could be confirmed by the absorption spectral change. The apparent association constant of NP was larger than that of PP. It is explained by that more hydrophobic NP can easily bind into the hydrophobic pockets of HSA. The photoexcited PP effectively induced damage of the tryptophan residue of HSA, through electron transfer-mediated oxidation and singlet oxygen generation. NP also induced HSA damage during photo-irradiation and the contributions of the electron transfer and singlet oxygen mechanisms were speculated. The electron transfer-mediated mechanism to the photosensitized protein damage should be advantageous for photodynamic therapy in hypoxic condition. The quantum yield of the HSA photodamage by PP was significantly larger than that of NP. The quenching effect of the naphthyl moiety is considered to suppress the photosensitized protein damage. In conclusion, the naphthalene substitution to the P(V)porphyrins can enhance the binding interaction with hydrophobic biomacromolecules such as protein, however, this substitution may reduce the photodynamic effect of P(V)porphyrin ring in aqueous media.

• Bulletin of the Korean Chemical Society
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• v.31 no.11
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• pp.3304-3308
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• 2010

Condensation of 4-amino-5-mercapto-3-($\alpha$-naphthyl)-s-triazole (1) with cyanogen bromide gives 6-amino-3-($\alpha$-naphthyl)-s-triazolo[3,4-b]-1,3,4-thiadiazole (2) which on condensation with chloranil yields 3,9-di-($\alpha$-naphthyl)-6,14-dioxo-bis-(s-triazolo[3,4-b]-1,3,4-thiadiazolo[3,2-b]imidazo[4,5-b]cyclohexane]-5a,6a-diene) (3). 3-($\alpha$-naphthyl)-s-triazolo[3,4-b]-1,3,4-thiadiazolo[3,2-b]imidazo[4,5-b]quinoxaline (4) is obtained by a similar condensation of (2) with 2,3-dichloroquinoxaline. The reaction of (2) with $\alpha$-haloketones followed by bromination affords 7-aryl-3-($\alpha$-naphthyl)-imidazo[2,1-b]-1,3,4-thiadiazolo[2,3-c]-s-triazoles (5) and their 6-bromo analogues 6 respectively. The structures of all newly synthesized compounds were established on the basis of elemental analyses, IR, $^1H$-NMR. The antibacterial and antifungal activities of all newly synthesized compounds have also been evaluated.

• Journal of the Korea Convergence Society
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• v.13 no.1
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• pp.161-166
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• 2022

HIF-2α is a transcription factor activated mainly in hypoxic condition known to play crucial roles in a wide variety of pathophysiological events including cancer, metabolic syndrome, arthritis etc. In this context, a number of N'-aryl isonicotinolyhydrazides, in which known pharmacophores are included, have been selected from commercial chemical library and tested for the inhibitory activities targeting HIF-2α in cultured HTB94 cell. HRE-luciferase and HIF-2α were introduced into the cell by transfection and adenoviri infection, respectively and the reporter gene assay discovered the potency of 2-hydroxy-1-naphthyl structure. Accordingly, the scaffold has been adjusted based on this structure and subjected to anti-HIF-2α activity test, identifying 2 compounds as HIF-2α inhibitors. The activities were confirmed by false positive test. This study has been performed via the convergence of biology and chemistry and the results may be useful for discovering novel inhibitors and HIF-2α biology studies, and contribute to the development of therapeutic agents.

• Journal of the Korean Society of Tobacco Science
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• v.20 no.1
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• pp.71-79
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• 1998

Haemolyph carboxylesterases induced in diapausing pupae of Helicoverpa assulta Guenee were investigated. Increase in the activity of the electrophoresed isozyme bands were observed during the diapausing pupae. The isozymatic composition exhibited remarkable alterations represented as disappearance and induction of some isozyme bandsp which were identified as carboxylesterase (CE) on the basis of their specificities to inhibitors. Much higher activity of the induced CE was shown in reaction with $\beta$-naphthyl acetate ($\beta$-Na) than $\alpha$-naphthyl butyrate ($\alpha$-Nb), representing the high regioselectivity to $\beta$-naphthyl group. Optimal temperature for the enzyme activity was different to the substrates used 37$^{\circ}C$ in $\beta$-Na and 4$0^{\circ}C$ in $\alpha$-Nb, respectively. However, the optimal pH for the enzyme activity was the same as 7.5 regardless of the substrates used, and relatively high thermostability of the CE was demonstrated by showing the denaturation at high temperature (50~55$^{\circ}C$).

• Korean Chemical Engineering Research
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• v.46 no.2
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• pp.279-285
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• 2008

The etherification of 2-naphthol with ethanol has been carried out over various solid acid catalysts. CNS, CNSWS, SCMS, MCF, and SBA-15 with and without sulfonic acid were used in this study as solid acid catalysts. The conversion of 2-naphthol and the selectivity of 2-naphthyl ethyl ether were obtained at reaction temperature = $180^{\circ}C$, $LHSV=1h^{-1}$, ethanol/2-naphthol molar ratio = 20 using a fixed-bed down flow reactor. The conversion of 2-naphthol and the selectivity of 2-naphthyl ethyl ether over silica group catalysts were higher than them over carbon group catalysts. The conversion of 2-naphthol was 70-90% and the selectivity of 2-naphthyl ethyl ether was more than 90% over silica group solid acid catalysts. It was performed XRD, SEM, TEM, and $NH_3-TPD$ to characterize solid acid catalysts.

• Archives of Pharmacal Research
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• v.18 no.4
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• pp.277-281
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• 1995

An anticoagulant, 4-hydroxy-3-[1, 2, 3, 4-tetrahydro-3-[4-(4-trifluoromethylbenzyloxy)phenyll-1 -naphthyl]coumarin (Flocoumafen) was synthesized in 8 steps starting from phenylacetyl shloride and anisole. The key step in the synthesis involves the reaction of 3-(4-methoxyphenyl)-1-teralol with 4-hydroxycoumarin to give 4-hydroxy-3 [1, 2, 3, 4-tetrahydro-3-[4-emthoxyphenyl]-1-naphthyl]coumarin.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.187.3-188
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• 2003

Structure-activity relationship studies of allylamine type of antimycotics were carried out to evaluate the effect of naphthyl and methyl portion of naftifine. Compounds with 4-fluorphenyl, 2-fluorophenyl, 2,4-dichlorophenyl, 2,6-dichlorophenyl, 4-nitrophenyl, and 2,3-dihydro-benzo[l,4]dioxin-6-yl instead of naphthyl group with hydrogen, methyl, and ethyl in the place of methyl in naftifine were synthesized and tested their in vitro anti-fungal activity against five different fungi. Eight compounds showed significant antifungal activity against T. mentagrophytes. (omitted)