• Analytical Science and Technology
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• v.25 no.1
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• pp.50-59
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• 2012

In this study, the effect of humidity change on DNPH cartridge sampling efficiency for carbonyl compounds (CCs) has been investigated. For this analysis, gaseous standard of 6 different CCs (formaldehyde (FA), acetaldehyde (AA), propionaldehyde (PA), butyraldehyde (BA), isovaleraldehyde (IA), and valeraldehyde (VA)) was calibrated after derivatization with three types of DNPH cartridge products. Their calibration results derived at RH values between 0 and 80% were then compared against liquid phase standards. If the results of our analysis are compared by the RH values between 20 and 80%, the effect of RH can be distinguished between light and heavy CCs. For lighter CCs (like FA and AA), there was no significant change. However, for the ones heavier than PA, there was fairly noticeable increase in relative recovery ratio in RH value between 20 and 80%. Such patterns are seen consistently from all three DNPH products tested for comparison. The results of our analysis suggest that proper correction for RH change may be needed for heavier CCs by the cartridge method.

• Bulletin of the Korean Chemical Society
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• v.27 no.5
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• pp.663-666
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• 2006

Carnosine, homocarnosine and anserine might act as anti-oxidants and free radical scavengers in vivo. In the present study, the protective effects of carnosine and related compounds on the $H_2O_2$-mediated cytochrome c modification were studied. Carnosine, homocarnosine and anserine significantly inhibited the oligomerization of cytchrome c induced by $H_2O_2$. All three compounds also inhibited the formation of carbonyl compound and dityrosine during the incubation of cytochrome c with $H_2O_2$. These compounds effectively inhibited the peroxidase activity in the cytchrome c treated with $H_2O_2$. The results suggested that carnosine, homocarnosine, and anserine might protect cytochrome c against $H_2O_2$-mediated oxidative damage through a free radical scavenging.

• Applied Biological Chemistry
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• v.37 no.3
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• pp.216-220
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• 1994

Organoanisyltitanium compounds which have chlorine or isopropoxy group as ligand were synthesized and purely isolated. These new compounds were proved to be stable at $0^{\circ}C$ under argon atmosphere for some weeks. They react readily at low temperature with carbonyl compound, especially aldehyde and ketone, to coresponding alcohols. In competition reaction of aldehyde/ketone pair these organotitanium species showed complete aldehyde selectivity.

• Journal of Korean Society for Atmospheric Environment
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• v.14 no.E
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• pp.41-58
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• 1998

In this study, a wide range of volatile organic constituents of environmental tobacco smoke (ETS) were determined using an environmental chamber, where ETS is the sole source of target compounds. ETS was generated in an environmental chamber by a number of different cigarettes, including the Kentucky reference cigarette and eight different commercial brands. More than 30 compounds were measured simultaneously for a total of twelve experimental runs. The target compounds are classified into three major classes, i.e. vapor phase ETS markers including 3-ethnylpyridine (3-EP) and nicotine, carbonyl compounds including formaldehyde, and volatile organic compounds (VOCs). The results from the chamber study were used to generate characterized ratios of selected VOCs to 3-EP, a vapor phase ETS marker. Emission factors for VOCs associated with ETS were also estimated. The characteristic ratios appeared to be generally in good agreement with published data obtained by environmental chamber studies similar to this study. This implies that the ratios may be useful for identifying and quantifying the impact of ETS as a source of target compounds in 'real world' indoor environments, which is affected by a complex mixture of multi-sources. The environmental chamber method described here provides a direct and reliable method to compare the ETS generated by different cigarettes. The method can also be applied to the simultaneous determination of many different ETS components.

• Bulletin of the Korean Chemical Society
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• v.15 no.2
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• pp.154-161
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• 1994

Studies have been conducted to explore single electron transfer (SET) induced photocyclization reactions of N-(trimethylsilylmethylthioalkyl)phthalimides (alkyl=ethyl, n-propyl, n-butyl, n-pentyl, and n-hexyl). Photocyclizations occur in methanol in modest to high yields to produce cyclized products in which phthalimide carbonyl carbon is bonded to the carbon of side chain in place of the trimethylsilyl group. Mechanism for these photocyclizations involving intramolecular SET from sulfur in the ${\alpha}$-silylmethylthioalkyl groups to the singlet excited state phthalimide moieties followed by desilylation of the intermediate ${\alpha}$ -silylmethylthio cation radicals and cyclization by radical coupling is proposed. In contrast, photoreactions of N-(trimethylsilylmethylthioalkyl)phthalimides in acetone follow different reaction routes to produce another cyclized products in which carbon-carbon bond formation takes place between the phthalimide carbonyl carbon and the carbon ${\alpha}$ to silicon and sulfur atoms via triplet carbonyl hydrogen abstraction pathway. The normal singlet SET pathway dominates this triplet process for photoreactions of these substances in methanol while the triplet process dominates the singlet SET pathway for those in acetone. The efficient and regioselective cyclization reactions observed for photolyses in methanol represent synthetically useful processes for construction of medium and large ring heterocyclic compounds.

• Korean Journal of Food Science and Technology
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• v.10 no.4
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• pp.387-393
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• 1978

Lipid oxidation is one of the major factors affecting on deterioration of nutritional quality in dried fish products. In this paper, the relationship between oxidized products of lipid and brown pigments, free amino acids and available lysine during the storage of dried sea eel, Muraesox cinereus, was investigated. And the inhibiting effect of antioxidant to lipid oxidation and its role to the protein quality were also discussed. From the results, TBA and carbonyl value rapidly increased while amino-N and available lysine diminished during hot air drying. This suggests that drying conditions greatly affected to the oxidation of lipid and making amino acids 'unavailable'. TBA value increased up to 20 days, and hereafter gradually diminished. Increase in TBA and carbonyl value and formation of fat oxidative brown pigment were closely related to the loss of free amino-N and available lysine. The loss of available lysine seemed to be affected by the formation of unsaturated carbonyl compounds rather than saturated carbonyl compounds. By the treatment of antioxidant, the loss of amino acids and available lysine was somewhat retarded. This may suggests that the oxidation of lipid or oxidative browning reactions are functioning to the loss of available lysine. In antioxidant treated sample, 23% of amino-N to the total amino-N in the fresh sample was lost after 20 days storage at $30^{\circ}C$ while the loss of amino-N to 39% in case of the control, and afterward the value treated to be slightly reduced or remained steady.

• YAKHAK HOEJI
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• v.30 no.5
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• pp.203-207
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• 1986

2-Aminobenzamide reacts with not only keton radical but also carbonyl group in carboxylic acid, to form easily -N-C-N-novel ring cyclization as a result I and V. In addition, it reacts with 1, 2-cyclohexadione or benzil, whitch are both 1, 2-diketone compounds, at the both ketone radical sites to give V or VII respectively. On the reaction with dimethone, however, which has 1, 3-diketone radical, it reacted with only one carbanyl group and VI was produced. We investigated the reaction with cr-ketoester such as ethyl pyruvate and diethyl rnesoxalate. In the reaction with ethylpyruvate, amine group in 2-aminobenzamide reacted not with ketone radical but carbonyl group in ester (product VIII). On the other hand, diethyl measoxalate reacted at the ketone radical site rather than the ester site (product IX).

• Bulletin of the Korean Chemical Society
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• v.35 no.7
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• pp.2029-2032
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• 2014

Magnetically nano-$CoFe_2O_4$ efficiently catalyzes oxidation of primary and secondary benzylic and aliphatic alcohols to give the corresponding carbonyl products in good yields. The reactions were carried out in an aqueous medium at room temperature in the presence of oxone (potassium hydrogen monopersulfate) as an oxidant. In addition, the catalysts could be reused up to 6 runs without significant loss of activities. Catalyst was characterized by SEM, XRD and IR.

• BMB Reports
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• v.46 no.2
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• pp.119-123
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• 2013

Methyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline (salsolinol), an endogenous neurotoxin, is known to perform a role in the pathogenesis of Parkinson's disease (PD). In this study, we evaluated oxidative modification of cytochrome c occurring after incubation with salsolinol. When cytochrome c was incubated with salsolinol, protein aggregation increased in a dose-dependent manner. The formation of carbonyl compounds and the release of iron were obtained in salsolinol-treated cytochrome c. Salsolinol also led to the release of iron from cytochrome c. Reactive oxygen species (ROS) scavengers and iron specific chelator inhibited the salsolinol-mediated cytochrome c modification and carbonyl compound formation. It is suggested that oxidative damage of cytochrome c by salsolinol might induce the increase of iron content in cells, subsequently leading to the deleterious condition which was observed. This mechanism may, in part, provide an explanation for the deterioration of organs under neurodegenerative disorders such as PD.

• Bulletin of the Korean Chemical Society
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• v.5 no.1
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• pp.32-37
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• 1984

The photoreaction of 2, 3-benzo-1, 1-diphenyl (or dimethyl)-1-sila-2-cyclobutene (9 or 10) with an aldehyde or ketone results in 1:1 cycloadduct of [4 + 2] type. In the reactions of 2, 3-benzo-1, 1-dimethyl-1-sila-2-cyclobutene (10) with acetone and butanone, another 1:1 adducts (13) were also formed, respectively. The following facts indicate that the formation of adduct involves an attack of a triplet carbonyl compound on the silicon of the benzosilacyclobutene, an $S_H2$ process. (1) Even when the reaction of 9 with acetophenone was carried out under conditions such that more than 99% of incident light was absorbed only by acetophenone using the filter solution of aq. cupric sulfate, the same adduct was still formed. (2) When the reaction of 9 with acetone was carried out under oxygen atmosphere, only trace amount of adduct was formed.