• Title/Summary/Keyword: Methylene

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Silica Supported Ammonium Acetate: An Efficient and Recyclable Heterogeneous Catalyst for Knoevenagel Condensation between Adehydes or Ketones and Active Methylene Group in Liquid Phase

  • Gupta, Raman;Gupta, Monika;Paul, Satya;Gupta, Rajive
    • Bulletin of the Korean Chemical Society
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    • v.30 no.10
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    • pp.2419-2421
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    • 2009
  • A simple and efficient method has been developed for Knoevenagel condensation between aldehydes or ketones and active methylene group by stirring in methylene chloride at 60 ${^{\circ}C}$ under heterogeneous conditions using silica supported ammonium acetate. The products are obtained in excellent yields and are in a state of high purity. The structures of the products were confirmed by IR, $^1H$ NMR and mass spectral data and comparison with authentic samples available commercially.

A Fatal Case of Methylene Chloride Poisoning (염화메틸렌 중독에 의한 사망 1례)

  • Jeong, Kyoung Sook;Lim, Hyun-Sul
    • Journal of The Korean Society of Clinical Toxicology
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    • v.7 no.1
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    • pp.41-43
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    • 2009
  • A 52-year-old man was found dead in the driver's seat of his tank lorry. The tank lorry was used to transport industrial wastewater to a disposal plant; the material was transferred into a storage tank with the help of compressed air. The wastewater contained methylene chloride and 2-chloropyridine. No respiratory protective equipment was used while working under these conditions. The autopsy report showed extensive edema and congestion of the brain, lung, and intraperitoneal organs. The concentrations of methylene chloride in lung and brain were reported at 398 and 67 mg/kg, respectively.

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Neuromodulation on neurogenic contraction of electrical nerve stimulation on isolated renal artery of rabbit (토끼 적출 신동맥에 있어서 전기자극에 의한 신경성 수축작용의 neuromodulation 효과)

  • Kim, Joo-heon;Hong, Yong-geun
    • Korean Journal of Veterinary Research
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    • v.36 no.4
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    • pp.821-828
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    • 1996
  • To elucidate the neuromodulation of neuropeptide Y and $\alpha,\;\beta$-methylene ATP on the neurogenic contraction of electrical perivascular nerve stimulation and the contractile response of noradrenaline from polygraph in the isolated renal artery of rabbit. 1. The neurogenic contraction induced by perivascular nerve stimulation was the voltage-dependent manner(10-100V) in the isolated renal artery of rabbit. 2. Neuropeptide Y(0.1uM) and $\alpha,\;\beta$-methylene ATP(1uM) increased the contractile responses of noradrenaline in the isolated renal artery of rabbit. 3. Neuropeptide Y(0.1uM) and $\alpha,\;\beta$-methylene ATP(1uM) increased the neurogenic contraction of electrical perivascular nerve stimulation in the isolated renal artery of rabbit. These results suggest that neuropeptide Y and $\alpha,\;\beta$-methylene ATP neuromodulated on the neurogenic contraction of electrical perivascular nerve stimulation on the isolated renal artery of rabbit.

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Anticancer Activity of Natural Products including Salvia miltiorrhiza (단삼 등 천연물의 항암작용)

  • 김옥희;정수연;박만기;류항묵;양지선
    • Biomolecules & Therapeutics
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    • v.7 no.1
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    • pp.29-34
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    • 1999
  • The cellular growth inhibition of 20 natural products was screened using SRB (sulforhodamine B) assay against 4 human cancer cell lines(SNU-1, SNU-C$_{4}$, Hep3B, Kato III). Ethanol extracts of Salvia miltiorrhiza, Saussurea lappa and Chelidonium majus showed potent anticancer activity among them, and further, it was fractionated into methylene chloride, hexane and methanol. Methylene chloride and methanol fraction of Salvia radix showed significant inhibitory activity against 4 human cancer cell lines. The effect of Salvia miltiorrhiza on anticancer activity in vitro models was evaluated with methylene chloride fraction of Salvia miltiorrhiza. Life span of ICR mice implanted with sarcoma-180 was increased by 40-61% and BDF$^{1}$ mice implanted with L1210 was increased by 66-89% upon intraperitoneal administration with methylene chloride fraction of Salvia miltiorrhiza. Based on these result, we suggested that Salvia miltiorrhiza showed anticancer activity on the in vivo and in vitro models

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A Study on Local Segmental Motions of Methylene Chain in Poly(Butylene Terephthalate) in Solution Phase

  • NamGung, Hyeon;O, Jeong Rae;Lee, Jo Ung
    • Bulletin of the Korean Chemical Society
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    • v.21 no.11
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    • pp.1071-1076
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    • 2000
  • Temperature dependent data of 13C spin-lattice relaxation times and NOE factors for methylene carbons at 50.3MHz and 125.5 MHz have been used to probe the local chain dynamics of poly(butylene terephthalate) (PBT) in solution phase. The interpretation of the relaxation data for methylene chain carbons in PBT was attempted on the basis of several proposed motional models, among which the DLM model was found to be superior. Analysis based on the DLM model indicated that the motion of the $OCH_2groups$ was more restricted compared with the central methylene carbon, which is consistent with conclusions from solid state experiments reported by other investigators. Librational amplitudes of terminal and central carbon of PBT were estimated to be $29.84^{\circ}$ and $32.01^{\circ}respectively.

Presence of cis-11, 12-Methylene Octadecanoic Acid in the Oils of Ternstroemia gymnanthera (후피향 종실의 cis-11, 12-Methylene Octadecanoic acid에 관한 연구)

  • Kim, Seong-Jin;Joh, Yong-Goe;Lim, Hee-Ryeong;Choi, Eun-Jin;Kim, Tae-Sook
    • Korean Journal of Food Science and Technology
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    • v.23 no.1
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    • pp.68-75
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    • 1991
  • The seed oil of Ternstroemia gymnanthera. a species of the Ternstroemiaceae, is mainly composed of triglyceride(92.4%), followed by polar lipids(5.9%), sterol(1.2%) and pigments(0.5%). This oil contains 4.8% of cis-11, 12-methylene octadecanoic acid(lactobacillic acid) in the fatty acid composition of the total oil. This identification is based on information from non-urea inclusion formation, silver nitrate impregnated silica gel column and gas liquid chromatography, $^1H-&\;^{13}C-nuclear$ magnetic resonance and mass spectroscopy. Smaller amounts(0.1%) of presumptive 9, 10-methylene hexadecanoic acid(dihydro malvalic acid) is also detected. The major fatty acids in this oil are C18 : 1(36.1%), C18: 2(30.9%), C16: 0(15.1%), C16: 1(7.6%) and C18: 0(3.4%).

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Methylene Blue-stained Interstitial Cells are Electrically Active in the Myenteric Board Freshly Prepared from the Murine Small Intestine

  • Lee, Kyu-Pil;Jeon, Ju-Hong;So, In-Suk;Kim, Ki-Whan
    • The Korean Journal of Physiology and Pharmacology
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    • v.10 no.4
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    • pp.193-198
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    • 2006
  • Many gastrointestinal muscles show electrical oscillation, so-called 'slow wave', originated from interstitial cells of Cajal (ICCs). Thus, a technique to freshly isolate the cells is indispensable to explore the electrophysiological properties of the ICCs. To apply an enzyme solution on the serosal surface for cell isolation, the intestine was inverted and 0.02% trypsin solution and 0.04% collagenase solution were applied to serosal cavity. After the enzyme treatment, mucosal layer was removed and longitudinal muscle layer was gently separated from the rest of tissue. The thin layer was stretched in the recording chamber and mounted on an inverted microscope. Using ${\beta}-escine$, perforated whole cell patch clamp technique was used. Under a microscope, the tissue showed smooth muscle cells and interstitial cells around the myenteric plexus. Under voltage clamp condition, three types of membrane potential were recorded. One group of interstitial cells, which were positive to methylene blue and CD34, showed spontaneous outward current. These cells had bipolar shape and were considered as fibroblast-like cells because of their peculiar shape and arrangement. Another group, positive to c-kit and methylene blue, showed spontaneous inward current. These cells had more rounded shape and processes and were considered as ICCs. The third, positive to c-kit and had granules containing methylene blue, showed quiet membrane potentials under the voltage-clamp mode. These cells appeared to be resident macrophages. Therefore, in the freshly isolated thin tissue preparation, methylene blue could easily identify three types of cells rather than morphological properties. Using this method, we were able to study electrical properties of fibroblast and residential macrophage as well as myenteric ICCs.