• Title/Summary/Keyword: Sulfoxide

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A METHOD OF MUCOSA CULTURE (구강점막의 배양에 관한 연구)

  • Choi, Byung-Ho;Yoo, Jae-Ha
    • 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.

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Synthesis and Tautomerism of Novel Quinoxalines (Part I) (새로운 Quinoxaline류의 합성과 토토머화 현상 (제1보))

  • Ho Sik Kim;Jin Hee Kim
    • 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.

Kinetics and Mechanism of the Pyridinolysis of O,O-Dimethyl S-Aryl Phosphorothioates in Dimethyl Sulfoxide

  • Barai, Hasi Rani;Lee, Hai-Whang
    • Bulletin of the Korean Chemical Society
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    • v.32 no.7
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    • pp.2339-2344
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    • 2011
  • Kinetic studies for the reactions of O,O-dimethyl Z-S-aryl phosphorothioates with X-pyridines have been carried out in dimethyl sulfoxide at 85.0 $^{\circ}C$. The Hammett and Br$\"{o}$nsted plots for substituent X variations in the nucleophiles are biphasic concave upwards with a break point at X = H, while those for substituent Z variations in the leaving groups are linear. The negative sign of the cross-interaction constant (${\rho}_{XZ}$) implies that the reaction proceeds through a concerted mechanism for both the strongly and weakly basic pyridines. The magnitude of ${\rho}_{XZ}$ (= -0.35) for the strongly basic pyridines is greater than that (${\rho}_{XZ}$ = -0.15) for the weakly basic pyridines, indicating a change of the nucleophilic attacking direction from frontside for the strongly basic pyridines to backside for the weakly basic pyridines. The early transition state is proposed on the basis of the absence of positive deviations from both the Hammett and Br$\"{o}$nsted plots for the strong ${\pi}$-acceptor, X = 4-Ac, and small values of ${\rho}_{XZ}$ and ${\beta}_X$.

Kinetics and Mechanism of the Benzylaminolysis of O,O-Dimethyl S-Aryl Phosphorothioates in Dimethyl Sulfoxide

  • Adhikary, Keshab Kumar;Barai, Hasi Rani;Lee, Hai-Whang
    • Bulletin of the Korean Chemical Society
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    • v.32 no.12
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    • pp.4304-4308
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    • 2011
  • Kinetic studies of the reactions of O,O-dimethyl Z-S-aryl phosphorothioates with X-benzylamines have been carried out 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 for substituent X variations in the nucleophiles are discrete with a break region between 4-Me and H, while the Hammett plots (log $k_2$ vs ${\sigma}_Z$) for substituent Z variations in the leaving groups are linear. The sign of the cross-interaction constant (${\rho}_{XZ}$) is positive for both the strongly and weakly basic nucleophiles. Greater magnitude of ${\rho}_{XZ}$ (= 2.54) value is observed with the weakly basic nucleophiles compared to with the strongly basic nucleophiles (${\rho}_{XZ}$ = 0.17). The deuterium kinetic isotope effects ($k_H/k_D$) involving deuterated benzylamines [$XC_6H_4CH_2ND_2$] are primary normal ($k_H/k_D$ > 1). The proposed mechanism is a stepwise with a rate-limiting leaving group expulsion from the intermediate involving a frontside nucleophilic attack with a hydrogen bonded, four-center-type transition state for both the strongly and weakly basic nucleophiles.

Theoretical Study of Solvent Effect on Yield of Oxidative Addition Reaction (산화첨가반응의 수득률에 미치는 용매효과에 관한 이론적 연구)

  • Lee, Chul-Jae;Kim, Byung-So
    • 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.

Kinetics and Mechanism of the Benzylaminolysis of O,O-Diethyl S-Aryl Phosphorothioates in Dimethyl Sulfoxide

  • Adhikary, Keshab Kumar;Lee, Hai-Whang
    • 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.

Effects of newly synthesized benzimidazole derivatives on gastric H^+/K^+$ ATPase

  • Cheon, Hyae-Gyeong;Yum, Eul-Kgun;Kim, Sung-Soo
    • Archives of Pharmacal Research
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    • v.19 no.2
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    • pp.126-131
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    • 1996
  • The effects of various synthetic benzimidazole derivatives on gastric H^+/K^+$ATPase activity in vitro were examined. The results showed that the effects of substituents on the benzimidazole ring were not significant. However, replacement of sulfoxide connecting two ring systems to sulfide resulted in a completely inactive compound in vitro, suggesting the essential role of sulfoxide group in the inhibition. In addition, compounds with 5 or 6-membered oxacyclic substituents attached to the pyridine ring displayed the most effective inhibitory activity. Among these derivatives, AU-47 was the most potent, and detailed mechanistic studies with the compound were carried out. AU-47 inhibited gastricH^+/K^+$ATPase in a concentration and time dependent manner with 50% inhibition at $6\muM$. The presence of sulfhydryl reducing agents or substrate analogue protected H^+/K^+$ATPase from the inactivation. The inhibition by AU-47 was potentiated by acid pretreatment of the compound, suggesting the structural conversion of AU-47 into a more active intermediate which was favored in acidic condition. Consistent with in vitro results, AU-47 inhibited in vivo gastric acid secretion. The results suggest that AU47 is a relevant candidate for the development of new antiulcer agent.

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Anion Effects on the Aminolysis of Carboxyl-Containing Esters by Triamines in Dimethyl Sulfoxide

  • Suh Junghun;Kim Yongho;Chang Sae Hee
    • 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.

Comparison of Anti-Oxidative and Cox-2 Promoter Activities of Lepidoptera Extracts (Lepidoptera 추출물에 의한 항산화 및 Cox-2 프로모터 활성 비교)

  • Son, Hyeong-U;Heo, Jin-Chul;Lee, Sang-Han
    • Food Science and Preservation
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    • v.17 no.5
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    • pp.752-756
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    • 2010
  • Lepidoptera (butterflies) extracts, traditionally employed as medicines, have various biological activities. Five species of Lepidoptera (Papilio maackii, Papilio xuthus, Pieris rapae, Eurema hecabe, and Sasakia charonda) were extracted with distilled water (DW), dimethyl sulfoxide (DMSO), ethanol (EtOH), and methanol (MeOH). Each extract was analyzed for anti-oxidant and anti-inflammatory activities using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay method, the ferric reducing ability of plasma (FRAP) test, and a cyclooxygenase-2 (COX-2) promoter assay. The results suggest that Lepidoptera extracts have valuable anti-oxidant and anti-inflammatory properties, supporting the idea that the extracts may serve as a food biomaterial(s) preventing oxidative processes and inflammatory damage.

Efficient Development of Stable Recombinant Chinese Hamster Ovary (rCHO) Cell Lines to Produce Antibodies by Using Dimethyl Sulfoxide (DMSO) in Electroporation

  • Byun, Juyoung;Yoon, Sena;Jeong, Yunji;Oh, Uitaek;Cho, Sujin;Park, Jeongsoo;Jeong, Yongsu;Baek, Kwanghee;Yoon, Jaeseung
    • Journal of Microbiology and Biotechnology
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    • v.29 no.1
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    • pp.55-58
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    • 2019
  • Development of stable rCHO cell lines is still time consuming and labor intensive, although it is a critical step in the commercial development of recombinant antibodies. The current work demonstrates, for the first time, that electroporation of CHO cells with DMSO can enhance stable expression of recombinant antibodies in rCHO cells. Electroporation with DMSO resulted in an average 3.7-fold and 2.8-fold increases in expression levels of aflibercept and pembrolizumab, respectively, in pools of stable rCHO cells. It also resulted in an average of 2.2-fold and 2.6-fold increases in the expression of aflibercept and pembrolizumab, respectively, in single-cell derived rCHO clones. Simple batch cultures of rCHO cell clones with the highest expression produced 1.0 g/l for aflibercept and 1.4 g/l for pembrolizumab without a time-consuming gene amplification process. Electroporation with DMSO also shortened the development of rCHO cell lines to 2-3 months, allowing rapid establishment of stable rCHO cell lines with a desirable expression level antibodies.