• YAKHAK HOEJI
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• v.35 no.4
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• pp.314-318
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• 1991

A convenient method for the synthesis of indoprofen, which is a potent antiinflammatory agent, w described. Ethyl $\alpha$-(4-aminophenyl)propionate was prepared by nitration of ethyl $\alpha$-phenylpropionate, followed by reduction. Ethyl $\alpha$-[4-(1, 3-dioxo-2-iso-indolinyl)phenyl]propionate was obtained from condensation reaction of phthatic anhydride and ethyl $\alpha$-(4-aminophenyl)propionate. Indoprofen was prepared by reduction of ethyl $\alpha$-[3-(1, 3-dioxo-2-iso-indolinyl)phenyl]propionate with zinc dust-acetic acid, followed by hydrolysis of the resultant ethyl $\alpha$-[4-(1-oxo-2-iso-indolinyl)pheriyl]propionate.

• Journal of the Korea Institute of Military Science and Technology
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• v.6 no.1
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• pp.108-115
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• 2003

TNAZ is a high explosive material because it is a highly strained ring compound containing one nitramine and gem dinditro groups. 1-t-butyl-3-nitroazetidine which was used as an intermediate previously, which declined the overall yield in synthesizing TNAZ. We obtained 1-t-butyl-3-hydroxymethyl-3-nitroazetidine in 64% yield from advances process which was used in synthesis of 1-t-butyl-3-nitroazetidine. The reaction pathway, shortening of reaction time, together with improvement of yield were studied too. We have obtained TNAZ in 85% yield.

• YAKHAK HOEJI
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• v.38 no.5
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• pp.504-510
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• 1994

A facile synthesis of 2-aryl-5-benzoxazolepropionic acid derivatives(1 0a-d), which are potent antiinflammatory agent, is reported. Methyl ${\alpha}$-(p-hydroxyphenyl)propionate(5) was prepared from Friedel-Crafts reaction of isopropoxy benzene with methyl ${\alpha}$-chloro-${\alpha}$-(methylthio) acetate(1), followed by desulfurization, methylation and clevage of ether bond. Compounds(10a-d) were made from(5) by a sequence of nitration, reduction, formation of benzoxazole ring, and hydrolysis in good yields, respectively.

• Journal of the Korean Society of Industry Convergence
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• v.6 no.1
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• pp.73-80
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• 2003

We report herein synthetic results obtained six new types of bis-benzocrown ethers containing imine group. Bis crown ethers1~3 are aminobenzo-15-crown-5-ether linked with terephthalaldehyde, isophthalaldehyde, phthaldehyde respectively by imine reaction. Bis crown ethers1~3 are different distances in each crown ether rings. Bis crown ether 4 has large cavity in crown ethers. Functionalized crown ether 5 is synthesized amonobenzo-15-crown-5-ether and terephthaladehyde same ratio at one to one. Bis crown ether 6 has photosensitive linkage between crown ethers. Bis crown ether 7 is prepared by amonobenzo-15-crown-5-ether and triethyl ortho formate. 4'-Nitrobenzo-crown ethers and 3',4'-dinitrobenzo-crown ethers were prepared by nitration of benzo crown ethers, obtained from the reaction of catechol and oligoethylene glycol ditosylate. Crown ethers containing aldehyde group were synthesized from the reaction of 3,4-dihydroxybenzaldehyde and corresponding ditosylate respectively. The synthesized crown ethers were characterized respectively by IR, NMR, GC-Mass.

• The Journal of Internal Korean Medicine
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• v.25 no.2
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• pp.268-276
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• 2004

Objective : Peroxynitrite $(ONOO^-)$, formed from the reaction of $O_2^-$ and NO, is a cytotoxic species that can oxidize several cellular components such as proteins, lipids and DNA. It has been implicated in the aging process and age-related disease such as Alzheimer's disease, rheumatoid arthritis, cancer and atherosclerosis. The aim of this study was to investigate scavenging activities of $ONOO^-$ and its precursors. NO and $O_2^-$ and its scavenging mechanism using fluorescent probes, DCFDA, DAF-2 and DHR 123.. Methods : Psoralea corylifolia was crushed. The crushed Psoralea corylifolia was extracted 3 times, each time with 3 volumes of methyl alcohol at $60^{\circ}C$ for 24 h. The extract was filtered and evaporated under reduced pressured using a rotary evaporator to yield 16g. This was done to investigate scavenging activities of $ONOO^-$, NO, $O_2^-$ and its scavenging mechanism using fluorescent probes, DCFDA, DAF-2 and DHR 123. Results : After Psoralea corylifolia was added authentic $ONOO^-,\;{\cdot}\;O_2^-$ and NO was markedly scavenged. Also, $ONOO^-$ induced by $O_2^-$ and NO (these derived from SIN-1) was inhibited. The data showed a decrease in $ONOO^-$ mediated nitration of tyrosine through electron donation after Psoralea corylifolia was added. Data showed a dose-dependent correlation with inhibition of nitration of bovine serum albumin induced by $ONOO^-$, Furtheremore, LPS-induced ROS and RNS generation was blocked. Conclusions: These results suggest potential for use of Psoralea corylifolia as an effective $ONOO^-$ scavenger to counter the aging process and age-related diseases.

• Analytical Science and Technology
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• v.12 no.1
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• pp.34-39
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• 1999

Estrone such as estriol and estradiol can not be determined by votammetric methods, because these are electrochemically inactive in the potential windows for mercury drop electrode. Nitro-derivatives of estrone are electro active and nitration of estrone is accomplished by heating the solution involving estrone and sodium nitrite in a water-bath at $100^{\circ}C$ for 30 min. Such nitro-derivatives are determined directly by voltammetry. The electrochemical behavior for nitrated estrone was investigated by cyclic voltammetry. The trace estrone was determinated by differential pulse adsorptive cathodic stripping voltammetry. Nitrated estrone gives a well defined voltammetric wave at ca. - 0.61 V (vs. Ag/AgCl electrode). The electrochemical reaction was irreversible process in sodium borate buffer at pH 11 and nitrated estrone was strongly adsorbed on the surface of mercury electrode. The optimal experimental conditions for the determination of nitrated esterone were found to be 0.05 M sodium nitrate, 0.01 M sodium borate, pH 11.0, and an accumlation potential of 0.10 V (vs. Ag/AgCl). The detection limit was as low as $1{\times}10^{-9}M$ for estrone with 2 min accumulation time.

• Applied Chemistry for Engineering
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• v.9 no.1
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• pp.155-157
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• 1998

Dinitramide salts may be useful as effective solid oxidizers because of higher oxygen content than nitrate salts. 3-Nitramino-propanoate was given by base treatement in the retro-Michael reaction of N-nitro-4-azaheptanedioate, which was prepared by nitration of 4-azaheptanedioate using $HNO_3$-TFAA(trifiluoroacetic anhydride)-$Br_2$. The nitramino compound was treated wile $NO_2BF_4$ to give dinitramino compound which was subsequently reacted with bases to give dinitramide salts.

• Journal of the Korea Institute of Military Science and Technology
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• v.6 no.3
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• pp.74-85
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• 2003

NENA(nitratoethyl nitramine) compounds, especially BuNENA(N-butyl-N-(2-nitratoethyl)-nitramine), are of high interest to both rocket propulsion and military high explosives because of low sensitivity to many forms of stimuli, although they are less energetic than conventional nitrate ester plasticizers. One of advantages in using NENAs is that they provide higher impulse at any given flame temperature than conventional propellants do. BuNENA has better thermochemical characteristics(low melting point and low glass transition temperature), therefore has less tendency to crystallize out of matrices. BuNENA was successfully synthesized in a high yield by reaction of n-butyl aminoethanol and 98% nitric acid followed by dehydrogenation of salt mixture by $Ac_2$/$ZnCl_2$.

• Applied Chemistry for Engineering
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• v.10 no.6
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• pp.857-862
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• 1999

Aminated poly(ether sulfone)(APES) was prepared by amination of nitrated poly(ether sulfone)(NPES) after poly(ether sulfone)(PES) was nitrated with mixed acid of nitric acid and sulfuric acid(sulfuric acid is a catalyst). As a results of the FT-IR spectrum analysis, the nitration of PES was confirmed by the bands of asymmetric stretching and symmetric stretching of $NO_2$ group at 1537 and $1351cm^{-1}$, respectively. Also when the NPES was aminated, it was disappeared to absorbance peaks of $NO_2$ group. And It was confirmed by the bands of asymmetric stretching and symmetric stretching of $NH_2$ group at 3470 and $3374cm^{-1}$, respectively. The optimum condition of the nitration on PES(5 g; 21.55 mmol.) was 12 hr of reaction time, $120^{\circ}C$ of reaction temperature, nitric acid of 28.00 mmol. and sulfuric acid of 52.00 mmol. As a result of the elemental analysis of APES, reapeating unit per amine groups were induced to 0.89. The adsorption rate of NO gas was lower than that of silica gel and active carbon. But the adsorption capacity of NO gas was higher than that of these. When the APES was absorbed to NO gas, the chemical adsorption rate was lower than the physical adsorption rate. But the chemical adsorption capacity of it was higher than physical adsorption capacity.

• Journal of the Korean Chemical Society
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• v.18 no.4
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• pp.278-288
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• 1974

Starting from p-dichlorobenzene, 2-amino-4-chloroanisole could be prepared via a nitration, a methoxylation, and subsequent reduction. The repeated chlorination of 2-amino-4-chloroanisole resulted 2-amino-3,4,5-trichloroanisole without any isomeric products. The chlorination of 4-chloro-2-nitroanisole could easily give 2,4-dichloro-6-nitroanisole but polychlorination of the product could not be achieved at the atmospherical pressure. The repeated chlorination of 2-amino-4,6-dichloroanisole could give 2-amino-3,4,5,6-tetrachloroanisole, The Schiemann reaction of 2-amino-4-chloroanisole and 2-amino-4,6-dichloroanisole could give 2-fluoro-4-chloroanisole and 2-fluoro-4,6-dichloroanisole, respectively. The repeated chlorination of these fluorochloroanisoles could give 2-fluoro-3,4,5,6-tetrachloroanisole. In each chlorination process, the components of products were examined by means of NMR spectrometry and the chlorination reaction was repeated without isolating each isomeric product. The feasibility of the present routes of preparations was discussed in respects to the conveniency of reaction conditions and respective overall yields of the processes.