• Title/Summary/Keyword: acidic compounds

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Synthesis, Spectral and Antimicrobial Studies of Some N(2)-Substituted Tetrahydroindazoles

  • Amirthaganesan, Shanmugasundaram;Aridoss, Gopalakrishnan;Park, Keun-Soo;Lim, Kwon-Taek;Jeong, Yeon-Tae
    • Bulletin of the Korean Chemical Society
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    • v.31 no.5
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    • pp.1135-1142
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    • 2010
  • A series of N(2)-benzothiazolyl substituted tetrahydroindazoles has been synthesized via cyclic ${\beta}$ keto esters. Optimum reaction condition was found as acidic toluene and effect of higher acidity towards substituted hydrazines in situ was described. Synthesized compounds have been achieved as single isomer and characterized by using 1D and 2D NMR spectral reports. Antimicrobial screening was carried out for the synthesized compounds along with a series of N(2)-pyridyl tetrahydroindazoles.1 The results of the in vitro antimicrobial screening studies revealed that compounds 13, 16 against Staphylococcus aureus, 11 against Escherichia coli, 10-12, 16 against Pseudomonas aeruginosa and 12 against Klebsiella pneumoniae recorded almost two-fold better activity compared to the standard drug used.

Radioiodination-IV & V-Study on the radioiodination of organic compounds by a hydrogen peroxide procedure (방사성요오드화반응-IV,V보-과산화수소를 이용한 요오드표지 합성법의 검토)

  • You sun Kim;Tae young Kim
    • Journal of the Korean Chemical Society
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    • v.14 no.2
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    • pp.169-177
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    • 1970
  • A study was made on the radioiodination of organic compounds in presence of hydrogen peroxide both in aqueous and organic solvent systems. In case of the reaction of rosebengal, Hippuran, and 5-iodo-uracil the aqueous reaction system could give high labelling yield within a relatively short reaction time. Labelling yield of average 50% could be obtained within 30 minutes of reaction sequence. In cases of organic solvent systems (D.M.S.O., D.M.F., and Dioxane) the solvent system of D.M.S.O. could give better yield for neutral organic compounds, where as D.M.F. and Dioxane gave better labelling result for acidic materials. Especially, o-iodobenzoic acid, o-iodotoluene, and pentachlorophenol could be labelled better in organic solvent system.

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Synthesis of 1-Aryl-2-mercapto-4-aryl-1,6-dihydro-1,3,5-triaszine-6-thione and their Latentiation Products as Antithyroidal Agent

  • Methrotra, S.;Roychowdhury, P.K.;Pandey, K.K.;Srivastava, P.K.
    • Archives of Pharmacal Research
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    • v.18 no.5
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    • pp.356-360
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    • 1995
  • Two new 1-aryl-2-benzylmercapto-4-aryl-1,6-dihydro-1,3,5-triazine-6-thiones hvae been synthesized by known methods (Coerdeler et al., 1967). These triazines on treatment with thiourea as dealkylating agent, in acidic medium afforded the corresponding 1-ary-2-mercapto-4-aryl-1,6-dihydro-1,3,5-triazine-6-thione which on further reaction with different ${\alpha},{\;}{\beta}-unstaturated$ carbonyl compounds and aryl-cyanamide ydrochloride affordered the related adducts. Some of these compounds show appreciable antithyroidal activity.

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Production of Auxins and Auxin-like Compounds by Ginseng Growth-promoting Bacterium Pseudomonas fluorescens KGPP 207

  • Ten, Leonid N.;Lee, Mi Ja;Lee, Mee-Kyoung;Park, Hoon;Yoon, Jong Hyuk
    • Journal of Applied Biological Chemistry
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    • v.43 no.4
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    • pp.264-268
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    • 2000
  • High activity of acidic ethylacetate extract from the culture supernatant of ginseng growth-promoting bacterium Pseudomonas fluorescens KGPP 207 and its fractions were demonstrated through wheat coleoptile bioassay. The following auxins and auxin-like compounds were identified in these fractions by combined gas chromatography-mass spectrometry: indole-3-acetic acid, indole-3-acetic acid methyl and ethyl ester, indole-3-butyric acid, indole-3-lactic acid and its methyl ester, indole-3-propionic acid, indole-3-pyruvic acid, p-hydroxyphenyl acetic acid, p-hydroxyphenyl acetic acid methyl and ethyl ester, phenyl acetic acid and its methyl ester. The bacterium KGPP 207 belongs to the strain of P. fluorescens which produces plant growth regulators and its beneficial effect on the ginseng growth may be due to the formation of the identified compounds.

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Lipoxygenase Inhibition and Antioxidative Activity of Flavonoids from Paeonia moutan Seeds

  • Kim, Hyo-Jin;Chung, Shin-Kyo;Park, Sang-won
    • Preventive Nutrition and Food Science
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    • v.3 no.4
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    • pp.315-319
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    • 1998
  • Previously, the methanolic extract of Paeonia moutan seeds was found to potently inhibit soybean lipoxy-genase (SLO). Hence to isolate SLO inhibitor, the defattd methaniolic extract of the seeds was consecutively partitioned wiht ether, ethyl acetate,n-butanol ,adn water. The ether souble fraction showing strong inhibitory activity against SLO was further fractionated into a strongly acidic, a weakly acidic, and a neutral fractions. The strongly acidic components of the ether extract were successively subjected to chromatography on a silica gel, Sephadex LH-20, and preparative HPLC. Four phenolic compounds were isolated , and twio of them showing a strong SLO inhibition activity were identified as luteolin (IC50=2.32$\mu\textrm{g}$/ml) and 5,6,4'-trihydroxy-7,3'- dimethoxylflavone (IC50=0.31$\mu\textrm{g}$/ml) by UV, IR, 1H-& 13C-NMR, and MS spectroscopy. In addition, two flavonoids showed significantly antioxidative activity as strong as that of of $\alpha$-tocopherol (p<0.05) in the autoxidation system of linoleic acid. These results suggest that luteolin and 5,6,4'-trihydroxy-7,3'-dimethoxy-flavone may be used as a potential source of anti-inflammatory agents with antioxidative activity.

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CO2 Solubilities in Amide-based Brønsted Acidic Ionic Liquids

  • Palgunadi, Jelliarko;Im, Jin-Kyu;Kang, Je-Eun;Kim, Hoon-Sik;Cheong, Min-Serk
    • Bulletin of the Korean Chemical Society
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    • v.31 no.1
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    • pp.146-150
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    • 2010
  • A distinguished class of hydrophobic ionic liquids bearing a Br${\o}$nsted acidic character derived from amide-like compounds were prepared by a neutralization reaction of N,N-diethylformamide, N,N-dibutylformamide, 1-formylpiperidine, and $\varepsilon$-caprolactam with trifluoroacetic acid and physical absorptions of $CO_2$ in these ionic liquids were demonstrated and evaluated. $CO_2$ solubilities in these ionic liquids were influenced by the molecular structure of the cation and were apparently increased with the molar volume. Comparison based on a volume unit reveals that $CO_2$ solubilities in these liquids are relatively higher than those in imidazolium-based ionic liquids. Henry's coefficients calculated from low-pressure solubility tests at 313 to 333 K were used to derive the thermodynamics quantities. Enthalpy and entropy of solvation may share equal contributions in solubility.

The Influence of Curing Conditions on the Composition of Essential Oil of Burley Tobacco Leaves (버어리종 잎담배의 건조조건이 정유성분 조성에 미치는 영향)

  • 배성국;김도연;이윤환;김영회
    • Journal of the Korean Society of Tobacco Science
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    • v.24 no.2
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    • pp.75-81
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    • 2002
  • This study was performed to investigate the influence of curing conditions on the composition of essential oil during curing process of burley tobacco leaves. The curing conditions were the primed curing in vinyl house (house-curing), air-curing barn (air-curing) and stalk-curing in conventional curing house (stalk-curing). Total 90 compounds are identified from the steam volatile oils of harvest and cured tobacco leaves by GC and GC-MS, respectively. The major components were neophytadiene, hexadecanoic acid, 3,8,13-duvatriene-1,5-diols, oxide-9-methylene-3,13-duvadienols, solanone, megastigma-4,6,8-trien-3-ones, phenylacetaldehyde, $\beta$-phenylethyl alcohol, indole, dihydroactinidiolide and phytol. The amount of alcoholic compounds was decreased more than approximately 50% in cured leaves without regard to the curing conditions. $\beta$-Phenylethyl alcohol and 3,8,13-duvatriene-1,5-diols were decreased more in air curing and stalk curing than in house curing. The amounts of phenylacetaldehyde, solanone, $\beta$-damascone, $\beta$ -damascenone, oxysolanone and megastigma-4,6,8-trien-3-ones as ketonic compounds, dihydroactinidiolide and indole as miscellaneous compounds in air-cured and stalk-cured tobacco leaves were 2 times higher than those in house-cured leaves, while esteric and acidic compounds were not changed largely in content by curing conditions.

Flavor Components in the Filefish Processing (말쥐치 가공중 향기성분에 관하여)

  • LEE Jong-Ho;CHOI Byeong-Dae;LEE Kang-Ho;LEE Kun-Tae;KIM Tae-Soo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.22 no.3
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    • pp.121-128
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    • 1989
  • Volatile compounds were collected by simultaneous distillation extraction and carbon dioxide method, and analyzed by GC and GC-MS. The neutral fraction obtained from the whole steam volatile concentrate 55 kinds of components, phenolic fraction had 4 kinds of components, basic fraction had 13 kinds of components and 10 kinds of components were in acidic fraction. Alcohols, propanols, butanols, octanols, dodecanols etc. and aldehydes, pentanals, hexanal, 2-methyl-1-propanal, heptenal etc. were highly increased after boiled and roasted. And these compounds were contributed to formation of filefish flavor. The molecular ion peak of phenolic fraction was generally appeared in the range 100 to about 160. From the basic fraction, 2-methylpyrazine, 2,5-dimethylpyrazine, 2-ethyl-3,5-di-methylpyrazine and 2-methylpyridine were identified. The contents of basic compounds and furans obtained from the neutral fraction were increased at the higher heating temperature. The flavor of acidic fraction was influenced by the low molecular as isovaleric and valeric acid.

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The Wallach Rearrangement The Behaviour of Monosubstituted Azoxybenzenes in Strongly Acidic Solution (强酸溶液中에서의 Azoxybenzene 系化合物들의 轉移反應. Wallach 轉移反應)

  • Hahn, Chi-Sun
    • Journal of the Korean Chemical Society
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    • v.6 no.2
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    • pp.162-170
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    • 1962
  • The rearrangement reaction of azoxybenzenes into hydroxyazobenzenes in strongly acidic solution has been studied by an U. V. spectrophotometric method and by isolation of the rearranged compound. In all cases under investigation, it appeared that the oxygen atom in the azoxy group migrated to the unsubstituted ring, depending neither on the substituent already present in the other ring, nor on the distance between the oxygen atom and the eligible position; whereas, the position in the open ring, ortho or para, to which the oxygen migrates depends on the substituent already present in the other ring. In all compounds besides ${\alpha}$-and ${\beta}$-4-methyl azoxybenzene, the oxygen atom migrates to the para position. In the case of ${\alpha}$ and ${\beta}$-4-methylazoxybenzene, the oxygen atom migrates to the ortho position of the unsubstituted ring.

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A study on ionic character of antibiotics (항생물질(抗生物質)의 이온성상(性狀)에 관(關)한 연구(硏究))

  • Yu, Tae-Jong;Kim, Won-Kyung
    • Applied Biological Chemistry
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    • v.7
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    • pp.59-65
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    • 1966
  • The ionic character of antibiotics and suitable pH values for their extraction can simultaneously be determined by pH-chromatography. The authors utilized the analytical procedure in determining the ionic character of several antibiotics, followed by microbiological Rf determination. The folowing conclusions were made: (1) Antibiotics analyzed can be devided into four groups according to their ionic chracter, that is acidic, basic, neutral, and amphoteric compounds. (2) Penicillin and aureomycin are proved to be acidic, streptomycin to be basic, polymyxin-B to be neutral, and finally both chloromycetin and erythromycin to be amphoteric. The results on their ionic character with regard to their molecular structure were briefly discussed.

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