• Journal of the Korean Chemical Society
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• v.26 no.2
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• pp.114-115
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• 1982

• Bulletin of the Korean Chemical Society
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• v.26 no.5
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• pp.776-780
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• 2005

The kinetic studies of the reactions of $\alpha$-chloroacetanilides $(YC_6H_4NRC(=O)CH_2Cl;\;R=H\;(4)\;and\;CH_3$ (5)) with pyridines have been carried out in dimethyl sulfoxide at 95 ${^{\circ}C}$. The pyridinolysis rates are faster with 4 than with 5 whereas the aminolysis rates with benzylamines are faster with 5 than with 4. The Brønsted ${\beta}_X$ values are in the range from 0.30 to 0.32 and the cross-interaction constants, $\rho_{XY}$, are small negative values; $\rho_{XY}$ = -0.06 and -0.10 for 4 and 5, respectively. Based on these and other results, the pyridinolyses of $\alpha$-chloroacetanilides are proposed to proceed via a stepwise mechanism with rate-limiting addition of the nucleophile to the carbonyl group to form zwitterionic tetrahedral intermediate ($T^{\pm}$) followed by a bridged type transition state to expel the leaving group.

• Journal of the Korean Chemical Society
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• v.47 no.4
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• pp.345-353
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• 2003

The reaction of 6-chloro-3-methoxycarbonylmethylene-2-oxo-1,2,3,4-tetrahydroquinoxaline(5) or 3-methoxycarbonylmethylene-6-nitro-2-oxo-1,2,3,4-tetrahydroquinoxaline(6) with hydrazine hydrate gave 3-hydrazinocarbonylmethylene-2-oxo-1,2,3,4-tetrahydroquinoxalines(7, 8). The reaction of compound 7 or 8 with substituted benzaldehydes or heteroaromatic aldehydes afforded quinoxalines(9-14). Compounds showed the tautomerism between the enamine and methylene imine forms, and between the enamine, methylene imine and enaminol forms in dimethyl sulfoxide solution. The tautomer ratios were determined by the 1H NMR.

• Journal of Microbiology and Biotechnology
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• v.26 no.9
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• pp.1579-1585
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• 2016

Sugar esters are valuable compounds composed of various sugars and fatty acids that can be used as antibacterial agents and emulsifiers in toothpaste and canned foods. For example, fructose fatty acid esters suppress growth of Streptococcus mutans, a typical pathogenic bacterium causing dental caries. In this study, fructose laurate ester was chosen as a target material and was synthesized by a transesterification reaction using Candida antarctica lipase B. We performed a solvent screening experiment and found that a t-butanol/dimethyl sulfoxide mixture was the best solvent to dissolve fructose and methyl laurate. Fructose laurate was synthesized by transesterification of fructose (100 mM) with methyl laurate (30 mM) in t-butanol containing 20% dimethyl sulfoxide. The conversion yield was about 90%, which was calculated based on the quantity of methyl laurate using high-performance liquid chromatography. Fructose monolaurate (M_r 361) was detected in the reaction mixture by high-resolution mass spectrometry. The inhibitory effect of fructose laurate on growth of oral or food spoilage microorganisms, including S. mutans, Bacillus coagulans, and Geobacillus stearothermophilus, was evaluated.

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.3
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• pp.307-310
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• 1998

The present studies were undertaken to evaluate the effects of a low concentration of dimethyl-sulfoxide (DMSO) on in vitro maturation and development of bovine oocytes fertilized in vitro. Significantly more oocytes reached the metaphase stage of the second meiotic division in TCM-199 supplemented with $50{\mu}M$ DMSO than in the control medium (p < 0.05), and the highest rates of development up to the blastocyst stage were obtained when $50{\mu}M$ DMSO was added to the maturation and culture media (p < 0.05). The avarage of cell numbers of the blastocysts, expanded and hatched blastocysts cultured with $50{\mu}M$ DMSO were 81.7, 125.7 and 129.9 cells, respectively. The proportion of blastocysts with normal chromosome numbers was 90.5%. These results suggest that the addition of $50{\mu}M$ DMSO is beneficial for the maturation of bovine oocytes and production of the blastocysts with high quality.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.17 no.4
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• pp.331-336
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• 1995

To use cultured mucosa as a graft of full thickness, our laboratory has been involved in the development of techniques to grow epidermis together with connective tissue. Human oral mucosa was obtained at dental surgery. Under sterile conditions the tissues were cut into explants of 0.1 $cm^2$ which were placed in the center of 24 well tissue culture dishes and incubated in a growth medium. The growth medium used for epithelial was MEM(Minimum Essential Medium) supplemented with 10% fetal calf serum, 0.5% dimethyl sulfoxide, glutamine (0.292 g/l), epidermal growth factor (40 ug/ml), cholera toxin (30 ng/ml), hydrocortisone (2 ug/ml), insulin (40 ug/ml) and transferin (5 ug/ml). The medium for stratification of epithelial cells was MEM supplemented with 10% fetal calf serum, 0.5% dimethyl sulfoxide and glutamine (0.292 g/l). The medium used for fibroblasts was MEM supplemented with 10% fetal calf serum. With the three types of media used alternatively, a mucosa composed of epidermis and connective tissue was obtained after 3 weeks of culture.

• Journal of the Korean Chemical Society
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• v.47 no.3
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• pp.241-249
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• 2003

The reaction of 3-(1-ethoxycarbonyl)ethyl-1,2-dihydro-2-oxoquinoxaline (8) with hydrazine hydrate gave 3-(1-hydrazinocarbonyl)ethyl-2-hydroxyquinoxaline (9). The reaction of compound 9 with substituted benzaldehydes and heteroaryl aldehydes afforded 2-hydroxyquinoxalines (10-12), respectively. The reaction of compound 9 with alkyl (ethoxymethylene)cyanoacetates and ethoxymethylenemalononitrile resulted in the intramolecular cyclization to give the 5-amino-1-[2-(3-hydroxyquinoxalin-2-yl)propanoyl]-pyrazoles (13), respectively. Compounds 10-13 showed the tautomerism between the lactam and lactim forms in dimethyl sulfoxide solution. The tautomer ratios were determined by the $^1H$ NMR. The herbicidal and fungicidal activities of the synthesized compounds were investigated.

• Applied Chemistry for Engineering
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• v.21 no.5
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• pp.586-589
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• 2010

In present work, oxidative addition reaction of 1,3-cycleohexandion (1,3-CHD) with ethyl vinyl ether (EVE) was attempted utilizing $Ag_2CO_3$/celite (SC) reagent. In order to optimize reaction conditions, we surveyed several solvents for the production of dihydrofuran with the (SC) system. The yield of the acetonitrile (AN), dimethyl sulfoxide (DMSO), benzene (BZ), and heptane (HT) are given 78, 40, 15, and 10%, respectively. Therefore, we studied the solvent effects on yields by using PM3 and ZINDO/1 parameter of semi-empirical method of HyperChem7.0 molecular modeling program.

• Bulletin of the Korean Chemical Society
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• v.32 no.10
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• pp.3587-3591
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• 2011

The reactions of O,O-diethyl Z-S-aryl phosphorothioates with X-benzylamines are kinetically investigated in dimethyl sulfoxide at $85.0^{\circ}C$. The Hammett (log $k_2$ vs ${\sigma}x$) and Br$\ddot{o}$nsted [log $k_2$ vs $pK_a$(X)] plots are biphasic concave downwards for substituent X variations in the nucleophiles with a break point at X = H. The signs of the cross-interaction constants (${\rho}xz$) are positive for both the strongly and weakly basic nucleophiles. Considerably great magnitude of ${\rho}xz$ (= 6.56) value is observed with the weakly basic nucleophiles, while ${\rho}xz$ = 0.91 with the strongly basic nucleophiles. Proposed reaction mechanism is a stepwise process with a rate-limiting leaving group expulsion from the intermediate involving a backside nucleophilic attack with the strongly basic nucleophiles and a frontside attack with the weakly basic nucleophiles. The kinetic results are compared with those of the benzylaminolysis of O,O-diphenyl Z-S-aryl phosphorothioates.

• Bulletin of the Korean Chemical Society
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• v.10 no.1
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• pp.72-74
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• 1989

Aminolysis of various carboxyl-containing ester substrates by triamines was kinetically studied in dimethyl sulfoxide (DMSO) in the presence of p-toluenesulfonic acid (TSA) or in the presence of sulfuric acid and potassium iodide (KI). In the presence of TSA or KI, the pseudo-first-order rate constants ($k_o$) were proportional to the total amine concentration ($N_o$). This stands in marked contrast with the corresponding reactions carried out with sulfuric acid added as the sole additive, in which saturation kinetic behavior of ko with respect to No was manifested. This indicates that complex formation between the ester substrate and the amine is greatly suppressed by the addition of TSA or KI. The second-order rate constants obtained in the presence of TSA or KI were substantially greater than those measured in the absence of any additive. These kinetic features were explained in terms of tight interaction between the protonated amines with I- or TSA-. Thus, the results were related to the hydrogen bonding that involves DMSO, bisulfate ion, I-, TSA-, and the protonated forms of triamines.