• Journal of Preventive Medicine and Public Health
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• v.32 no.1
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• pp.88-94
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• 1999

Objectives. In order to gain a better understanding of the mechanism of DMF toxicity, recent studies have focused on hepatic drug metabolizing enzymes. In this study, we investigated the effects of DMF on the induction of P450 and the activities of other related enzymes in rat liver microsomes. Methods. DMF was administered to male Sprague Daweley rats by intraperitoneal injection at 0(control), 450(D1), 900(D2), 1,800(D3) mg DMF/kg body weight in olive oil once a day for three days. Hepatic P450 was measured by method of Omura and Sato. We evaluated selective assays for the three drug metabolizing cytochrome P450 isoenzymes 1A1, 2B1 and 2E1. Results. The content of microsomal protein, P450 and b5 were tended to be decreased in DMF treated group, but they were not statistically significant. The activity of NADPH-cytochrome P450 reductase was significantly increased dose dependently(p<0.01), but the activity of NADH-b5 reductase was decreased in the treated group(p<0.01). The activities of PROD and EROD were not significant between control and treated group. The activities of pNPH in the DMF treated groups were higher than that of the control group(p<0.01). When Western immunoblottings were carried out utilizing three monoclonal antibodies which were specific against P4501A1/1, P4502B1/2 and P4502E1, the strong density band corresponding to P4502E1 was observed with the microsomes obtained from the rats treated with DMF. But there were no significant increased in the P4501A1/2 and P4502B1/2 band densities in immunoblotting. Conclusions. These result suggested that P4502E1 was inducible by DMF and P4502E1 isozyme might be responsible for the hydroxylation of DMF to HMMF.

• Journal of the Korean Chemical Society
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• v.25 no.2
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• pp.110-118
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• 1981

Kinetics and mechanism for the reaction of substituted phenacyl bromides with substituted pyridines have been determined at 25, 35 and $45^{\circ}C$ in methanol and dimethylformamide by the conductivity method. The rate constants for the reaction of various pyridines with phenacyl bromide shown that electron-donating substituents in the pyridine increase the rate, while electron-attracting one decrease in both solvents. The effect of substituents in substrate, the rate being increased by electron-attracting substituents. This is as expected for nucleophilic attack of amines on the carbon atom. Isokinetic and $Br{\psi}nsted$ linear relationship were shown in the reaction of phenacyl bromide with pyridines in both solvent in which isokinetic temperature were obtained 614, $202^{\circ}K$ and ${\beta}$ values were 0.29, 0.36 in methanol and dimethylformamide respectively. In the case of the reaction of substituted phenacyl bromide with pyridines, isokinetic temperature decreases with increasing electron-attracting ability of the substituents in the phenacyl bromide, while the ${\beta}$ values were reverse. From the above results, it can be inferred that N…C bond formation decreases progressively from p-chloro- to p-methoxyphenacyl bromide and the bond formation predominates in DMF than methanol. The ${\rho}$ values of Hammett equation of the reaction of phenacyl bromide with substituted pyridines are negative in both solvent, but its value was larger negative in DMF than methanol and the ${\rho}$ value of that of substitutted substrates with pyridine was 0.3, the low value is ascribed to direct $S_N2$ attack of the nitrogen atom in pyridine ring at the methylene carbon.

• Applied Chemistry for Engineering
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• v.30 no.2
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• pp.155-159
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• 2019

As a part of improving the quality for the fraction of the waste plastics pyrolysis oil (WPPO), the recovery of paraffin components contained in the fraction was investigated by dimethylformamide (DMF) equilibrium extraction. The fraction of a distilling temperature of $120{\sim}350^{\circ}C$ recovered from WPPO by the simple distillation and the aqueous solution of DMF were used as a raw material and solvent, respectively. The concentrations of paraffin components ($C_{12}$, $C_{14}$, $C_{16}$ and $C_{18}$) contained in the raffinate decreased by increasing the mass fraction of water in the solvent at an initial state ($y_{w,0}$), whereas, the concentrations of paraffin components contained in the raffinate increased by increasing the mass ratio of the solvent to the feed at an initial state $(S/F)_0$. The concentrations of $C_{12}$, $C_{14}$, $C_{16}$ and $C_{18}$ paraffin components present in the raffinate recovered at $(S/F)_0=10$ were about 1.37, 2.0, 2.46 and 3.16 times higher than those of the raw materials, respectively. Recovery rates (residue rates present in raffinate) of paraffin components rapidly increased with increasing $y_{w,0}$, and decreasing $(S/F)_0$. The raffinate recovered through this study was expected to be used as a renewable energy.

• Journal of Adhesion and Interface
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• v.4 no.4
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• pp.22-27
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• 2003

Chemical modification of carbon nanotube (CNT) was carried out using $HNO_3$ and $H_2SO_4$ and characterized by analyzing the CNT before and after the modification using FT-IR and titration. Aggregation behaviors were investigated using a real-time video microscope after the chemically modified CNT(mCNT) had been dispersed in organic solvents such as toluene, dimethylformamide (DMF) and N-methylpyrrolidone (NMP) by ultrasonication. The mCNT showed better dispersion in polar sovents of DMF and NMP than the rCNT. CNT/ poly(methylmethacrylate) (PMMA) films were prepared from solution DMF/PMMA solutions. The films containing mCNT also revealed the improved dispersion.

• Archives of Pharmacal Research
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• v.15 no.1
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• pp.69-72
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• 1992

Pyrimidine bases and their mucleosides were oxidatively iodinated at C-5 position by the reaction of iodine in DMF (dimethylformamide) with MCPBA (m-chloroperbenzoic acid) under mild conditions. For uracil derivatives such as uracil 1a. 1, 3-dimethyluracil 1b, uridine 1c, and 2'-deoxyuridine 1d, the corresponding 5-iodo derivatives were obtained in high yields (71-95%). The iodination of cytidine 3a and 2'-deoxycytidine 3b was achieved in moderate yields (41-56%).

• Bulletin of the Korean Chemical Society
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• v.25 no.9
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• pp.1403-1407
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• 2004

Dielectric relaxation measurements on 3-nitrotoluene (3-NT) mixture of dimethylacetamide (DMA), dimethylformamide (DMF) and dimethysulphoxide (DMSO) have been carried out across the entire concentration range using Time domain reflectometry technique at 15, 25, 35 and $45^{\circ}C$ over the frequency range from 10 MHz to 20 GHz. For all the mixtures, only one dielectric loss peak was observed in this frequency range and the relaxation in these mixtures can be well described by a single relaxation time using Debye model. Bilinear calibration method is used to obtain complex permittivity ${\varepsilon}^{*}({\omega})$ from complex reflection coefficient ${\rho}^{*}({\omega})$ over frequency range 10 MHz to 20 GHz. The excess permittivity, excess inverse relaxation time, Kirkwood correlation factor, molar energy of activation are also calculated for these mixtures to study the solute-solvent interaction.

• Bulletin of the Korean Chemical Society
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• v.22 no.4
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• pp.357-361
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• 2001

Frequency spectra of the complex permittivity of 2-methoxyethanol (2-ME) with water, ethanol, dimethylsulphoxide (DMSO), N,N-dimethylformamide (DMF) and N,N-dimethylacatamide (DMA) have been determined over the frequency range of 10 MHz to 20 GHz at 25 $^{\circ}C$, using the Time domain reflectometry method, for 11 concentrations for each system. The static dielectric constant, dielectric constant at microwave frequency, relaxation time, excess dielectric parameters, and Kirkwood correlation factor have been determined. The relaxation in these systems within the frequency range can be described by a single relaxation time constant, using the Debye model. The parameters show a systematic change with the concentration.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.207-207
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• 2011

Aromatic nitriles possess versatile utilities and are indispensible not only in organic synthesis but also in chemical industry. In fact, the nitrile group is an important precursor for various functional groups such as aldehydes, amines, amidines, tetrazoles, amides, and their carboxyl derivatives. Representative methods for the preparation of organonitriles with cyanide-containing reagents are the Sandmeyer and Rosenmund-von Braun reactions. Recently, a catalytic route to aryl nitriles has been reported on the basis of the chelation-assisted C-H bond activation or metal-catalyzed cyanation of haloarenes. In those cyanation protocols, the "CN" unit is provided from metal-bound precursors of MCN (M=Cu, K, Na, Zn), TMSCN, or K3Fe(CN)6. Additionally, it can be generated in situ from nitromethane or acetone cyanohydrin. Herein, we report the first example of generating "CN" from two different, readily available precursors, ammonia and N,N-dimethylformamide (DMF). In addition, its synthetic utility is demonstrated through the Pd-catalyzed cyanation of arene C-H bonds.

• Bulletin of the Korean Chemical Society
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• v.29 no.4
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• pp.777-781
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• 2008

In this work, silver nanoparticles-containing polyacrylonitrile (PAN) solutions in N,N-dimethylformamide (DMF) were electrospun to be webs consisting of nanofibers. The inputted voltage and PAN content in the solution were fixed at 15 kV and 10 wt.% in DMF with 10 cm of tip-to-collector distance (TCD). The PAN/Ag nanofiber webs were stabilized by oxidation at 250 ${^{\circ}C}$ for 2 h in air and carbonized at 1000 ${^{\circ}C}$ for 2 h in $N_2$. The resultant diameter distribution and morphologies of the nanofibers were evaluated by scanning electron microscope analysis. The electrochemical behaviors of the nanofiber webs were also observed by cyclic voltammetry tests. It was found that the presence of silver nanoparticles in carbon nanofiber webs led to the increase of specific capacitance and the decrease of fiber diameters.

• Bulletin of the Korean Chemical Society
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• v.11 no.2
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• pp.89-94
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• 1990

The redox properties of 2-amino-1-cyclopentene-1-dithiocarboxylate anion (acdc) and its oxovanadium complex, $VO(acdc)_2$ have been investigated in dimethylformamide (DMF) with polarography and cyclic voltammetry. Bis(2-amino-1-cyclopentene-1-dithiocarboxylate) oxovanadium(IV) exhibits two polarographic oxidation waves and two reduction waves in the potential range from +0.50V to - 2.4V vs. the Ag/AgCl (DMF) reference electrode. The second oxidation wave appeared at - 0.08V is found to be reversible and is attributed to the formation of $VO(acdc)_2\;^+$. The first reduction process (at - 0.60V) is also reversible and this reduction process is caused by the electrode process of formation of $VO(acdc)_2$-species. The half wave potential for the reduction, V(IV)$\to$V(III) is more positive for oxovanadium complexes containing sulfur donor atoms than other VO(IV) complexes having oxygen or nitrogen donor atoms.