• Food Science of Animal Resources
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• v.30 no.4
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• pp.685-694
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• 2010

The present study investigated the combined effects of modified atmosphere packaging (MAP) and organic acid salts on the quality and shelf-life of Hanwoo ground beef patties. The ground beef containing 500 ppm of ascorbic acid was prepared with air-packaging (Air-P), high oxygen-MAP (70% $O_2$+30% $CO_2$/OxyMAP), and nitrogen-MAP (100% $N_2$/NitroMAP), in combination with organic acid salts (1500 ppm of sodium acetate and 500 ppm of calcium lactate). The samples were stored for 11 d at $5^{\circ}C$. The pH value of ground beef patties decreased during storage in all the treatments. The ground beef patties with organic acid salts showed relatively higher level of pH during storage compared with non-added patties (p<0.05). Lipid oxidation was accelerated in OxyMAP while it was delayed in NitroMAP treated with organic acid salts. Nitro-MAP treated with organic acid salts was effective in stabilizing the color characteristics of lightness (CIE $L^*$) and redness (CIE $a^*$) during storage. Oxygen content in MAP was shown to be a more important factor affecting color stability and lipid oxidation of ground beef than organic acid salts. The aerobic and anaerobic bacterial counts were reduced both in OxyMAP and NitroMAP (p<0.05), and the lactic acid bacteria was inhibited by Oxy-MAP (p<0.05). Coliform bacteria decreased during storage as pH value was decreased in all treatments. According to the sensory evaluation, the ground beef patties in NitroMAP showed the best quality among all treatments during storage. Therefore, Hanwoo ground beef patties added with sodium acetate and calcium lactate and packed with NitroMAP showed better quality characteristics than other treatments. This packaging method is recommended and could be utilized for packaging hanwoo ground beef patties for improving quality and extending shelf-life.

• Archives of Pharmacal Research
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• v.23 no.1
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• pp.31-34
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• 2000

An efficient procedure for the preparation of 7,8-dichloro-6-nitro-1H-1,5-benzodiazepine-2,4-(3H, 5H)-dione(7) as a potential lead compound for the NMDA receptor glycine binding site antagonist, starting from readily available 4,5-dichloro-2-nitroaniline(8), is described. The key step in the synthesis involves the cyclization of malonic ester amide 10 to compound 11.

• Journal of the Korean Chemical Society
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• v.20 no.1
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• pp.91-94
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• 1976

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.236.2-237
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• 2003

Several studies of terbenzimidazoles and bibenzimidazoles suggested that benzimidazoles, especially 5-nitro-2-(para-methoxyphenyl)benzimidazole. possess topoisomerase I inhibition activities. In order to find out the structure activity relationship of 5-nitro-2-phenyl-benzimidazoles. eight derivatives that are substituted at the para position of 2-phenyl moiety were selected, synthesized ＆ evaluated considering their electronic or lipophilic parameters. (omitted)

• Bulletin of the Korean Chemical Society
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• v.30 no.8
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• pp.1767-1770
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• 2009

The Henry (nitroaldol) reaction proceeds under mild conditions with catalytic amount of tetramethylethylenediamine (TMEDA) to afford $\beta$-nitro alkanol in considerably excellent yield. Structurally diverse aldehydes react with nitromethane in presence of 0.3 equiv of TMEDA under solvent-free condition at rt. The low catalytic loading and mild reaction condition are the key features of the catalytic method.

• Bulletin of the Korean Chemical Society
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• v.20 no.8
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• pp.929-934
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• 1999

2-( β-Alkoxyvinyl)-4-(1-hydroxyalkyl)pyrroles (14) were synthesized from 4-acylpyrrole-2-carboxylates (8) by sequential reduction of their acyl and alkoxycarbonyl groups to give 4-(1-hydroxyalkyl)pyrrole-2-carbalde-hydes (13) followed by Wittig reaction of the aldehydes with the ylide of alkoxymethylphosphonium chloride. Diels-Alder reaction of 2-(β-alkoxyvinyl)-4-(1-hydroxyalkyl)pyrroles with trans-methyl β-nitroacrylate gave 6-alkoxy-3-(1-hydroxyalkyl)-5-nitro-4,5,6,7-tetrahydroindole-4-carboxylates (3).

• Applied Biological Chemistry
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• v.17 no.3
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• pp.149-176
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• 1974

Eight substituted diphenyl ether herbicides and some of their photoproducts were studied in terms of solution phase photolysis under simulated environmental conditions by using a Rayonet photochemical reactor. The test compounds absorbed sufficient light energy at the wavelength of 300 nm to undergo various photoreactions. All the photoproducts were confirmed by means of tlc, glc, ir, ms, and/or nmr spectrometry. The results obtained are summarized as follows: Solution phase photolysis of C-6989: An exceedingly large amount of p-nitrophenol formed strongly indicates the readiness of the ether linkage cleavage of this compound as the main reaction in all solvents used. Photoreduction of nitro to amino group(s) and photooxidation of trifluoromethyl to carboxyl group were recognized as minor reactions. Aqueous photolysis of p-nitrophenol: Quinone(0.28%), hydroquinone (0.66%), and p-aminophenol (0.42%) were confirmed as photoproducts, in addition to a relatively small amount of an unknown compound. The mechanisms of formation of these products were proposed to be the nitro-nitrite rearrangement via $n{\rightarrow}{\pi}^*$ excitation and the photoreduction through hydrogen abstractions by radicals, respectively. Solution phase photolysis of Nitrofen: Photochemical reduction leading to the p-amino derivative was the main reaction in n-hexane. In aqueous solution, the photoreduction of nitro to amino group and hydroxylation predominated over the ether linkage cleavage. Nucleophilic displacement of the nitro group by hydroxide ion and replacement of chlorine substituents by hydroxyl group or, to a lesser extent, hydrogen were also observed as minor reactoins. Solution phase photolysis of MO-338: Photoreduction of the nitro to amino group was marked in the n-hexane solution photolysis. In the aqueous solution, photoreduction of the nitro substituent and hydroxylation were the main reactions with replacement of chlorine substituents by the hydroxyl group and hydrogen, and cleavage of the ether linkage as minor reactions. Photolyses of MC-4379, MC-3761, MC-5127, MC-6063, and MC-7181 in n-hexane and cyclohexane: Photoreduction of the nitro group leading to the corresponding amino derivative and replacement of one of the halogen substituents by hydrogen from the solvent used were the key reactions in each compound. Aqueous photolysis of MC-4379: Cleavage of the ether linkage, replacement of the carboxymethyl by hydroxyl group, hydroxylation, and replacement of the nitro by hydroxy group were prominent with photoreduction and dechlorination as minor reactions. Aqueous photolysis of MC-3761: Cleavage of the ether linkage, replacement of the carboxymethyl by hydroxyl group, and photoreduction followed by hydroxylation were the main reactions. Aqueous photolysis of MC-5127: Replacement of carboxyethyl by hydrogen was predominant with ether linkage cleavage, photoreduction, and dechlorination as minor reactions. It was obvious that the decarboxyethylation proceeded more readily than decarboxymethylation occurring in the other compounds. Aqueous photolysis of MC-6063: Cleavage of the ether linkage and photodechlorination were the main reactions. Aqueous photolysis of MC-7181: Replacement of the carboxymethyl group by hydrogen and monodechlorination were the remarkable reactions. Cleavage of the ether linkage and hydroxylation were thought to be the minor reactions. Aqueous photolysis of 3-carboxymethyl-4-nitrophenol: The photo-induced Fries rearrangement common to aromatic esters did not appear to occur in the carboxymethyl group of this type of compound. Conversion of nitro to nitroso group was the main reaction.

• Journal of the Korea Institute of Military Science and Technology
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• v.4 no.1
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• pp.198-206
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• 2001

The structure of Yb complex with 3-nitro-1,2,4-triazol-5-one(NTO), $[Yb(NTO)3(H2O)4].5H2O$ has been investigated by X-ray diffraction method. Crystallographic data for the title compound : monoclinic, C2/c, $a=36.925(2){\AA},$ b=6.6770(4)${\AA},$ c=25.6376(15)${\AA},$ {\beta}=130.978(1)^{\circ},$ V=4772.0(5)${\AA}^3,$ Z=8, $D_c,=1.952\; Mg/m^3.$ The intensity data were collected on a Broker SMART diffractometer equipped with a CCD area detector using Mo $K\alpha$ radiation. The structure was solved by direct method and refined by full-matrix least-squares calculations to a final R value of 0.0424 for 4727 independent reflections and 335 parameters. The three carbonyls of three NTO anions and four ligand water molecules which are formed the pentagonal bipyramid are coordinated with $Yb^{3+}$ and also five water molecules are included in the form of the crystal water in the molecular structure.

• Korean Journal of Environmental Agriculture
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• v.17 no.3
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• pp.239-245
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• 1998

To investigate the formation of bound residue with soil organic materials by oxidative coupling, nitroaromatics and their reduced metabolites, the insecticide parathion and the herbicide asulam were incubated with oxidoreductase, laccase or horseradish peroxidase, in the presence or absence of humic monomers. Most of aminotoluenes and amino-nitrophenols were completely transformed while most of nitrotoluenes and nitrophenols remained unchanged by a lactase or horseradish peroxidase in the presence or absence of humic monomers. Amino-nitrotoluenes were not transformed without humic monomers, but the addition of various humic monomers caused a considerable difference in the transformation of amino-nitrotoluenes by a lactase or horseradish peroxidase. Amino-nitrotoluenes were most transformed in the presence of catechol, syringaldehyde and protocatechuic acid. The insecticide parathion with nitro group and its metabolite were not mostly transformed in the presence or absence of humic monomers. The herbicide asulam with amino group remained unchanged without humic monomers as well, but the stimulating effect on the transformation of asulam was caused by the addition of catechol, syringaldehyde, protocatechuic acid or caffeic acid with a lactase.

• Bulletin of the Korean Chemical Society
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• v.35 no.6
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• pp.1789-1793
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• 2014

Pseudo-first-order rate constants ($k_{obsd}$) have been measured spectrophotometrically for the reactions of 5-nitro-8-quinolyl nicotinate (4) and 5-nitro-8-quinolyl isonicotinate (5) with alkali metal ethoxides (EtOM; M = K, Na and Li) in anhydrous ethanol at $25.0{\pm}0.1^{\circ}C$. The plots of $k_{obsd}$ vs. [EtOM] curve slightly upward for the reactions with EtOK and EtONa but are linear for the reactions with EtOLi and for those with EtOK in the presence of 18-crown-6-ether. Dissection of $k_{obsd}$ into $k_{EtO^-}$ and $k_{EtOM}$ (i.e., the second-order rate constants for the reactions with the dissociated $EtO^-$ and ion-paired EtOM, respectively) has revealed that the reactivity increases in the order $EtO^-{\approx}EtOLi$ < EtOK < EtONa for the reactions of 4 and EtOLi < $EtO^-$ < EtOK < EtONa for the reactions of 5. Comparison of the kinetic results for the reactions of 4 and 5 with those reported previously for the corresponding reactions of 5-nitro-8-quinolyl benzoate (2) and picolinate (3) has revealed that the esters possessing a pyridine ring (i.e., 3-5) are significantly more reactive than the benzoate ester 2 due to the presence of the electronegative N atom (e.g., 2 << 3 < 4 < 5). It has been concluded that $M^+$ ion catalyzes the reactions of 3-5 by increasing the electrophilicity of the reaction center through a five-membered cyclic transition state (TS) for the reaction of 3 and via a four-membered cyclic TS for the reactions of 4 and 5.