• Title/Summary/Keyword: Potential acid

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Design, Synthesis and Anticonvulsive Activities of Potential Prodrugs Linked by Two-carbon Chain

  • Zhao, Long-Xuan;Moon, Yoon-Soo;Basnet, Ar-Jun;Park, Jae-Gyu;Kim, Eun-kyung;Kim, Dae-Ok;Jeong, Tae-Cheon;Jahng, Yurng-Dong;Choi, Jong-Won;Lee, Eung-Seok
    • Archives of Pharmacal Research
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    • v.26 no.10
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    • pp.785-795
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    • 2003
  • For the development of new anticonvulsive agents, GABAmimetics such as nipecotic acid, isonipecotic acid, ${\gamma}-aminobutyric$ acid (GABA), ${\gamma}-vinyl$ GABA (vigabatrin) and valproic acid were covalently coupled through an ester bond by a two-carbon linker chain as potential prodrugs and evaluated for their anticonvulsive activities.

Therapeutic Potential of Membrane Fatty Acid Modifiaction in Tumor Cells

  • Shon, Yun-Hee;Park, Kun-Young;Kim, Kwang-Soo
    • Preventive Nutrition and Food Science
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    • v.1 no.1
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    • pp.143-150
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    • 1996
  • The membrane fatty acid composition of tumor cell can be modified either in cell by altering the lipid composition of the medium of during growth in animals by changing the dietaty fat composition. These modifications are associated with changes in membrane physical properties and certain cellular functions, including carrier-mediated transport and enzyme contained within the membrane. Such effects influence the transport of nutrients and chemotherapeutic agents in cancer cells .Fatty acid modification also can enhance the sensitivity of the neoplastic cell to chemotherapy. The alteration in plasma membrane composition will be affected through dietary supplementations and the potential value to cancer patients could be a better understanding of the effects of diet on responsiveness of neoplasms to chemotherapy, i.e. cancer patients' chances for a "cure" can be improved by diet changes prior to treatment.

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A Regiospecific One-Pot, Three Component Synthesis of 4-Aryl-6,8-dimethylpyrimido[4,5-c]pyridazine-5,7(6H,8H)-diones as New Potential Monoamine Oxidase Inhibitors

  • Khalafy, Jabbar;Rimaz, Mehdi;Panahi, Leila;Rabiei, Hossein
    • Bulletin of the Korean Chemical Society
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    • v.32 no.7
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    • pp.2428-2432
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    • 2011
  • A series of new 4-aryl-6,8-dimethylpyrimido[4,5-c]pyridazine-5,7(6H,8H)-diones have been synthesized via three component reaction of 1,3-dimethylbarbituric acid with arylglyoxals in the presence of hydrazinium dihydrochloride in ethanol. All of these derivatives may act as potential monoamine oxidase inhibitors.

Activity Guided Isolation of Antioxidant Tannoid Principles from Anogeissus latifolia

  • Govindarajan, Raghavan;Vijayakumar, Madhavan;Shirwaikar, Annie;Rawat, Ajay Kumar Singh;Mehrotra, Shanta;Pushpangadan, Palpu
    • Natural Product Sciences
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    • v.11 no.3
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    • pp.174-178
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    • 2005
  • Oxidative stress is an important causative factor in several human chronic diseases, such as atherosclerosis, cardiovascular disorders, mutagenesis, cancer, several neurodegenerative disorders, and the aging process. Phenolics and tannins are reported to be good antioxidants. Anogeissus latifolia (Combretaceae) bark has been used in the Indian traditional systems of medicine for curing a variety of ailments, but scientific validation is not available till date. Hence the present study was undertaken to isolate antioxidant compounds by activity-guided isolation. Inhibtion of diphenyl picryl hydrazyl (DPPH) and Xanthine oxidase along with photochemiluminescence assay were used as bioassay for antioxidant activity. Activity guided isolation was carried out using silica column and the compounds were quantified using HPLC. Ethyl acetate and butanol fraction exhibited potent antioxidant activity. Bioassay-guided isolation led to isolation of ellagic acid (1) and dimethyl ellagic acid (2) as the main active compounds, which along with gallic acid were quantified by HPLC. Thus we conclude that these three major tannoid principles present in A. latifolia, are responsible for the antioxidant potential and possibly their therapeutic potential.

Photocurrents in the $SnO_2$ Photoelectrochemical Cell Sensitized by Rhodamine B ($SnO_2$광전기화학 셀에서 Rhodamine B에 의한 광전류)

  • Hyun-Jin Min;Gi-Bum Kim;Jeong-A Yu;Kang-Jin Kim
    • Journal of the Korean Chemical Society
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    • v.37 no.2
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    • pp.213-219
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    • 1993
  • The electrochemical spectral sensitization of $SnO_2$ electrodes with rhodamine B was studied. Photocurrent was measured in the presence of a variety of supersensitizers including ascorbic acid and KI. In the presence of ascorbic acid, the increase in the concentration of ascorbic acid, pH of the solution, or the potential applied to $SnO_2$ up to 0.6 V vs. SCE enhanced the photocurrent. However, ascorbic acid produced considerably high dark current due to its low reduction potential. On the other hand, KI produced low but stable photocurrent. The results, together with the solvent effect on the photocurrent, were taken into account to elucidate the mechanism of photosensitization in the presence of ascorbic acid or KI.

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Antioxidant Compounds Isolated from the Roots of Phlomis umbrosa Turcz.

  • Nguyen, Duc Hung;Le, Duc Dat;Zhao, Bing Tian;Ma, Eun Sook;Min, Byung Sun;Woo, Mi Hee
    • Natural Product Sciences
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    • v.24 no.2
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    • pp.119-124
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    • 2018
  • Two triterpenoids, arjunolic acid (1), belleric acid (2), five phenylethanoids, martynoside (3), orobanchoside (4), 3,4-dihydroxyphenethylalcohol-6-O-caffeoyl-${\beta}$-$\text\tiny{D}$-glucoside (5), leucosceptoside B (6), lunariifolioside (7), four phenolic acids, ferulic acid (8), syringic acid (9), vanillic acid (10), 4-hydroxybenzoic acid (11), and one lignan, (+)-syringaresinol-${\beta}$-$\text\tiny{D}$-glucoside (12), were isolated from the roots of P. umbrosa. All isolated compounds were explored for their antioxidant potential in the DPPH and ABTS assays. In DPPH assay, compound 5 showed high antioxidant capacity. Compounds 3, 4, 6, and 7 displayed considerable antioxidant activities. In addition, compounds 5-7 exhibited potential antioxidant capacities in the ABTS assay.

The Effects of Additives on the Electropolishing of Copper Through Via (구리 Through Via 전해연마에 미치는 첨가제의 영향 연구)

  • Lee, Suk-Ei;Lee, Jae-Ho
    • Journal of the Microelectronics and Packaging Society
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    • v.15 no.1
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    • pp.45-50
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    • 2008
  • The effects of electrolytes and additives on the electropolishing of 50 and $20{\mu}m$ diameter copper via were investigated to flatten 3D SiP through via. The termination time was determined with analysis of applied potential on anode and cathode to avoid excess electropolishing. Acetic acid played a role of accelerator and glycerol played a role of inhibitor in phosphoric acid electrolytes. The overplated copper on the through via was effectively electropolished in the phosphoric electrolytes with acetic acid and glycerol addition. The electropolishing was terminated at the point of abrupt change of applied potential to remove only overplated copper on the through via.

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In-situ Characterization of Electrochemical and Frictional Behaviors During Copper CMP

  • Eom, Dae-Hong;Kang, Young-Jae;Park, Jin-Goo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.07a
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    • pp.227-230
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    • 2004
  • As the organic acids were added in the slurry, zeta potential of alumina was changed to negative value and IEP value was shifted from alkaline to acidic pH. In citric acid based slurry, Cu surface continuously dissolved and etching depth linearly increased. On the contrary, passivation layer was grown on Cu surface in oxalic acid based slurry. As the platen rotation speed increased, Preston coefficient decreased in both slurries. With oxalic acid based slurry, at low velocity, removal rate is high value because of high friction force compared to citric acid based slurry. As platen velocity increased, removal of Cu in citric acid based slurry became higher value than oxalic acid based slurry. Typical lubrication behaviors were observed in both slurries. As Sommerfeld number increased, COF values gradually decreased and then re-increased. It indicated that lubrication was changed to direct contact or semi-direct contact mode to hydro-lubrication mode.

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