• 제목/요약/키워드: Aromatic Aldehydes

검색결과 163건 처리시간 0.026초

Vanillin의 신미량검출법 (제1보)

  • 이상섭;김용덕
    • 약학회지
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    • 제3권1호
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    • pp.48-50
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    • 1957
  • The micro-assay methods of vanillin have been shown quite few, though several methods have been introduced for determination. A new sensitive micro-determination of vanillin, applying the yellow color reaction of vanillin and anillin, is shown in this paper. The absorption maximum of the yellow coloring matter, 4-Oxy-3-methoxy-henzal aniline, was 435 mu. The one dimensional ascending paper chromatographic method is applyed for isolation of vanillin from the mixed sample. The microdetection of vanillin is studied only in this paper. Vanillin was detected by the yellow spot on paper trip by the coloring reagent of aniline after several hours paper strip chromatographic at the following condition; paper strip ................ 2.5 X 35cm Whatman Filter Paper No.2 developing Solvent ......... petroleum-benzene-methanol n-butanol-water coloring agent ............. aniline. The Rf-value on petroleum benzene and methanol was 0.63 and that on n-butanol and water was 0.90. The minimum detectable amount of vanillin by this method was 10 micrograms. It is recommendable, if interference substances as aromatic aldehydes present, that the application of this aniline reaction and Foline Denis reaction on the same paper chromatogram is appreciable.

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New Synthesis of 2-Substituted Imidazo[2, 1-b]thiazoles and their Antimicrobial Activities

  • Mahfouz, A.Abdel Aziz;Elhabashy, F.M.
    • Archives of Pharmacal Research
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    • 제13권1호
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    • pp.9-13
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    • 1990
  • 4, 5-Diphenyl-2-mercaptiomidazole (I) was reacted with hydraziodyl halides IIa-d togive the S-alkyl derivatives III-a-d. Cyclization of IIIa-d afforded imidazo[2, 1-b]-thiazole derivatives Vla, b and VII. Treatment of 1 with a-chloroethylacetoaccetate (IV) gave ethyl 2(4, 5-diphenyl-2-imidazolinylthio)-3-keto-butyrate (V). Compound V coupled with benzendiazonium chloride to give the corresponding phenylhydrazo compound IIId. On heating V with polyphosphoric acid, cyclization took place and 2-acetyl-5, 6-diphenyl-imidazo [2, 1-b] thiazol-3-one (VIII) was obtained. The compound VIII was condensed with aromatic aldehydes to yield the cinnamoyl derivatives 1Xa, b. The antimicrobial activities of compounds IIIa-d, V, VIa, VII were examined.

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Chemical Components of Atractylodes japonica Rhizome Oil

  • Chang, Kyung-Mi;Kim, Gun-Hee
    • Preventive Nutrition and Food Science
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    • 제15권2호
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    • pp.147-151
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    • 2010
  • The volatile aroma constituents of Atractylodes japonica rhizome were separated by steam distillation extraction method using a Clevenger-type apparatus, and analyzed by gas chromatography-mass spectrometry (GC/MS). The yield of the essential oil from Atractylodes japonica was 1.0% (v/w), and its color was pale yellow. Forty-five volatile flavor compounds, which make up 93.86% of the total peak area, were tentatively identified in the rhizome oil. The oil contained 32 hydrocarbons (79.19%) with sesquiterpene hydrocarbon predominating, 3 esters (12.46%), 4 alcohols (0.11%), 1 ketone (0.01%), 2 aldehydes (0.02%), and 3 miscellaneous compounds (2.07%).

An Efficient and Environmentally Friendly Procedure for the Synthesis of Some Novel 8-Benzylidene-4-phenyl-3,4,5,6,7,8-hexahydro-1H-quinazolin-2-ones/thiones using Tetrabutylammonium Hexatungstate as a Reusable Heterogeneous Catalyst under Solvent-Free Conditions

  • Ghashang, Majid;Mansoor, Syed Sheik;Aswin, Krishnamoorthy
    • Bulletin of the Korean Chemical Society
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    • 제34권11호
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    • pp.3289-3294
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    • 2013
  • An efficient method for the preparation of 8-benzylidene-4-phenyl-3,4,5,6,7,8-hexahydro-1H-quinazolin-2-ones/thiones from the reaction of aromatic aldehydes with cyclohexanone and urea or thiourea in the presence of Tetrabutylammonium hexatungstate, $[TBA]_2[W_6O_{19}]$, as an efficient, inexpensive catalyst under thermal and solvent-free conditions has been developed. Good yields, short reaction times, straightforward workup, reusability of the catalyst, and green conditions are the most obvious advantages of this procedure.

Brønsted Acidic Ionic Liquids as Efficient Catalysts for Clean Synthesis of Carbamatoalkyl Naphthols

  • Tavakoli-Hoseini, Niloofar;Heravi, Majid M.;Bamoharram, Fatemeh F.;Davoodnia, Abolghasem
    • Bulletin of the Korean Chemical Society
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    • 제32권3호
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    • pp.787-792
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    • 2011
  • Under mild conditions and without any additional organic solvent, synthesis of carbamatoalkyl naphthols could be carried out in the present of two halogen-free Br${\phi}$nsted acidic ionic liquids, 3-methyl-1-(4-sulfonic acid)butylimidazolium hydrogen sulfate and N-(4-sulfonic acid)butylpyridinium hydrogen sulfate. A wide range of aromatic aldehydes easily undergo condensation with $\beta$-naphthol and methyl or benzyl carbamate to afford the desired products of good purity in excellent yields. The present methodology offers several advantages such as a simple procedure with an easy work-up, short reaction times, and excellent yields. The catalysts could be recycled and reused for several times without substantial reduction in their catalytic activities.

The First Report on Chemoselective Biguanide-Catalyzed Henry Reaction under Neat Conditions

  • Alizadeh, Abdolhamid;Khodaei, Mohammad M.;Abdi, Gisya;Kordestani, Davood
    • Bulletin of the Korean Chemical Society
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    • 제33권11호
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    • pp.3640-3644
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    • 2012
  • An efficient synthetic method for direct Henry reaction catalyzed by a biguanide; namely metformin, as an organosuper-base, between a variety of aromatic and aliphatic aldehydes and nitromethane under neat conditions has been developed. Convenient procedure for removal of the catalyst, chemoselective acquiring of ${\beta}$-nitroalcohols as predominant products, as far as possible short reaction time with excellent conversions are advantages of the developed protocol.

Volatile Aroma Composition of Chrysanthemum indicum L. Flower Oil

  • Chang, Kyung-Mi;Kim, Gun-Hee
    • Preventive Nutrition and Food Science
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    • 제13권2호
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    • pp.122-127
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    • 2008
  • The aroma constituents of Chrysanthemum indicum L. were separated by the hydro distillation extraction method using a Clevenger-type apparatus, and were analyzed by gas chromatography-mass spectrometry (GC/MS). The yield of Chrysanthemum indicum L. flower oil was 2.0% (w/w) and the color was light golden yellow. Sixty-three volatile flavor components, which make up 89.28% of the total aroma composition of the flower oil, were tentatively characterized. This essential oil contained 35 hydrocarbons (48.75%), 12 alcohols (19.92%), 6 ketones (15.31%), 3 esters (4.61%), 5 aldehydes (0.43%), 1 oxide (0.22%), and 1 miscellaneous component (0.04%). ${\alpha}$-Pinene (14.63%), 1,8-cineol (10.71%) and chrysanthenone (10.01%) were the predominant volatile components in Chrysanthemum indicum L., an aromatic medicinal herbaceous plant.

Mannich-type Reactions of in Situ Generated N-Acyliminium Ions from α-Amido p-Tolylsulfones with Silyl Enolates

  • Lee, Sang-Hyeup;Kadam, Santosh T.
    • Bulletin of the Korean Chemical Society
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    • 제32권10호
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    • pp.3738-3742
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    • 2011
  • Bismuth tribromide ($BiBr_3$) catalyzed Mannich-type reactions of N-acyliminium ions which generated in situ from N-benzyloxycarbonylamino p-tolylsulfones have been developed. In the presence of catalytic amount of $BiBr_3$, N-benzyloxycarbonylamino p-tolylsulfones prepared from aromatic and aliphatic aldehydes reacted with silyl enol ether and silyl enol ester under mild reaction conditions to afford N-Cbz-protected ${\beta}$-amino ketones and N-Cbz-protected ${\beta}$-amino esters in moderate to good yield, respectively.

Microwave-Assisted One-Pot Synthesis of Octahydroquinazolinone Derivatives Catalyzed by Thiamine Hydrochloride Under Solvent-free Condition

  • Badadhe, Pravin V.;Chate, Asha V.;Hingane, Dattatraya G.;Mahajan, Pravin S.;Chavhan, Namdev M.;Gill, Charansingh H.
    • 대한화학회지
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    • 제55권6호
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    • pp.936-939
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    • 2011
  • Thiamine hydrochloride (VB1) has been used as an acid catalyst in organic synthesis. One pot three component Biginelli condensation of dimedone, urea/thiourea and substituted aromatic aldehydes catalyzed by 10 mol % of thiamine hydrochloride (VB1) in solvent free condition under microwave irradiation in good to excellent yields has been investigated. Utilization of microwave irradiation, simple reaction conditions, short reaction time, ease of product isolation, and purification makes this manipulation very interesting from an economic and environmental perspective.

Synthesis and Pharmacological Studies for New Benzotriazole and Dibenzodiazepine Derivatives as Antipsychotic Agents

  • El-Sabbagh, Osama I.;El-Nabtity, Sameh M.
    • Bulletin of the Korean Chemical Society
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    • 제30권7호
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    • pp.1445-1451
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    • 2009
  • New benzotriazoles (5-8) or dibenzodiazepine derivatives (11-18) were synthesized starting from 3-[(2-amino- 4,5-disubstitutedphenyl)amino]-5,5-disubstitutedcyclohex-2-enones (1-4) through internal coupling of their diazonium salts or internal Mannich reaction in the presence of aromatic aldehydes. Pharmacological evaluation of benzotriazole and dibenzodiazepine derivatives for their clozapine-like properties revealed that dibenzodiazepine 11 bearing 4-bromophenyl group exhibited the same antipsychotic activity as the reference drug clozapine while the activity of benzotriazole 7 was 25% lesser than that of clozapine. Moreover, compounds 7 and 11 did not show significant CNS depressant activity as well as no or slight neurotoxicity on contrast to clozapine when tested in mice using forced swim, rotarod and horizontal screen tests.