scholarly journals RESOLUTION OF A RACEMIC ISOLEUCINE MIXTURE BY USING METHYL L-MANDELATE

2016 ◽  
Vol 4 (3) ◽  
pp. 156
Author(s):  
Rani Maharani ◽  
Ace Tatang Hidayat ◽  
Dadan Sumiarsa ◽  
Achmad Zainuddin ◽  
Ika Wiani Hidayat
Keyword(s):  
Methyl Ester ◽  
Column Chromatography ◽  
Mandelic Acid ◽  
Steglich Esterification ◽  
Flash Column Chromatography

A methyl ester of L-mandelic acid was found to be an effective resolving agent for resolution of commercial DL-isoleucine. The resolution was based on Steglich esterification between methyl L-mandelate and Boc-DL-isoleucine. The two resolved isomers were easily separated by using a conventional flash-column chromatography, giving quantitatively good yields. Unfortunately, the methyl L-mandelate was found to be ineffective to resolve four stereoisomers of Fmoc- isoleucine.

Monodisperse oligo(δ-valerolactones) and oligo(ε-caprolactones) with docosyl (C22) end-groups

2020 ◽  
Vol 11 (26) ◽  
pp. 4228-4236
Author(s):  
José E. Báez ◽  
Kenneth J. Shea ◽  
Philip R. Dennison ◽  
Armando Obregón-Herrera ◽  
José Bonilla-Cruz
Keyword(s):  
Column Chromatography ◽  
End Groups ◽  
Flash Column Chromatography

Two different families of monodisperse oligoesters with α-hydroxyl-ω-docosyl (C22) terminal groups [oligo(δ-valerolactone) and oligo(ϵ-caprolactone)] were isolated by flash column chromatography (FCC).

VANILLINSÄURE ALS ENDPRODUKT DES ABBAUES VON ADRENALIN UND NORADRENALIN

1962 ◽  
Vol 39 (3) ◽  
pp. 385-394 ◽  
Author(s):  
Wilhelm Dirscherl ◽  
Helmut Thomas ◽  
Herbert Schriefers
Keyword(s):  
Melting Point ◽  
Ir Spectra ◽  
Paper Chromatography ◽  
Column Chromatography ◽  
Human Urine ◽  
Vanillic Acid ◽  
Mandelic Acid ◽  
Uv And Ir Spectra ◽  
Rat Livers

ABSTRACT In rat livers perfused with 3-methoxy-4-hydroxy-mandelic acid, formerly believed to be the endproduct of the metabolism of adrenaline and noradrenaline, three metabolites were detected by paper chromatography. After further purification by column chromatography, one of these substances was identified by melting point, shape of crystals, UV- and IR-spectra as vanillic acid. Perfusion with vanillic acid yielded only one metabolite in very small quantities. Because of its properties it is assumed to be a conjugate of vanillic acid. Hence vanillic acid, isolated in 1959 from human urine by Dirscherl & Schmidtmann, is the actual endproduct of the metabolism of adrenaline and noradrenaline.

scholarly journals Phytochemical study of aerial parts from Phlomis tuberosa L

2014 ◽  
Vol 14 ◽  
pp. 20-24 ◽  
Author(s):  
S Javzan ◽  
D Selenge
Keyword(s):  
Carboxylic Acid ◽  
Methyl Ester ◽  
1H Nmr ◽  
Column Chromatography ◽  
Methanol Extract ◽  
Iridoid Glycoside ◽  
Chloroform Fraction ◽  
Spectroscopic Methods ◽  
Phytochemical Study ◽  
Aerial Parts

Three iridoid glycoside lamiide(I), Ipolamiide(II) and ipolamiide(III) were isolated from N-butanol fractions obtained from the column chromatography of methanol extract from the aerial parts of Phlomis tuberosa. In addition, iridoid cyclopenta[c]pyran-4-carboxylic acid, 7-methyl-, methyl ester and phenol, 4-(3-hydroxy-1-propenyl)-2-methoxy were determined from the chloroform fraction of methanol extract of aerial parts from Phlomis tuberosa. Isolation and structural elucidation of compounds were accomplished by PTLC, TLC, CC and spectroscopic methods (UV, 13C and 1H NMR and DEPT, GC-MS). DOI: http://dx.doi.org/10.5564/mjc.v14i0.192 Mongolian Journal of Chemistry 14 (40), 2013, p20-24

scholarly journals ISOLASI SENYAWA ANTIOKSIDAN DALAM EKSTRAK HEKSANA KULIT BATANG MANGGIS HUTAN (Garcinia bancana Miq.)

2014 ◽  
Vol 16 (1) ◽  
pp. 17-23
Author(s):  
Sri Hartati ◽  
Masrukhan Masrukhan ◽  
Herry Cahyana
Keyword(s):  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Column Chromatography ◽  
Stem Bark ◽  
Hexane Extract ◽  
Molecular Formula ◽  
Dpph Method ◽  
Flash Column Chromatography ◽  
Layer Chromatography

Antioksidan adalah suatu senyawa yang dapat menangkap radikal bebas. Salah satu sumber anti oksidan alami adalah dari tumbuh-tumbuhan. Dalam usaha pencarian antioksidan baru, telah dilakukan identifikasi senyawa antioksidan dari ekstrak n-heksana kulit batang Garcinia bancana Miq dengan metode 1,1-difenil-2-pikrilhidrazil (DPPH). Metode isolasi dilakukan dengan cara  kombinasi kromatografi (Kromatografi kolom vacum, kromatografi kolom gravitasi, kromatografi lapis tipis  sentrifugal dan kromatografi lempeng tipis)  Penentuan struktur molekul berdasarkan analisis data spektroskopi UV-VIS, IR, LC-MS, NMR proton dan karbon. Dari  hasil isolasi didapatkan suatu senyawa isoprenil bezofenon dengan bobot molekul 466,22 dan  rumus molekul C28H34O6 dengan nama IUPAC 3-(3,4-dihidroksibenzoil)-4-hidroksi-8-8-dimetil-1,7-bis(3-metilbut-2enil) bisiklo (3.3.1) non-3-ene-2,9-dione atau disebut bacanone yang diduga senyawa baru. Dari proses isolasi juga ditemukan senyawa atsiri b- caryophyllene, α-humulene dan b-cadinene serta stigmasterol. Hasil uji aktivitas antioksidan ekstrak n-heksana dan hasil isolat murni menunjukkan IC50 berturut-turut 17,78 ppm dan 12,79 ppm dimana pembanding kuersetin adalah 9,90 ppm.Kata kunci:  Garcinia bancana, antioksidan, DPPH, 3-(3,4-dihidroksibenzoil)-4-hidroksi-8-8-dimetil-1,7-bis(3-metilbut-2enil)bisiklo(3.3.1)no-3-ene-2,9-dione, bacanone. Antioxidants are compounds that can capture free radicals. One source of natural antioxidant is from plants. On searching  for new antioxidant, identification of antioxidant compound of the n-hexane extract of the stem bark of Garciniabancana Miq was done by  1.1-diphenyl-2-pikrilhidrazil (DPPH) method. Isolation active compound were done by combination of chromatographic methods (Flash column chromatography, gravitation column chromatography, cetrifugal thin layer chromatography and thin layer chromatography) .Determination of molecular structure by analysis spectroscopic data of UV-VIS, IR, LC-MS, NMR proton and carbon.Isolation results were      isophrenyl bezophenon with molecular weight 466.22 and the molecular formula is C28H34O6 IUPAC name 3 - (3,4-dihydroxybenzoil)-4-hydroxy-8-8-dimethyl-1,7-bis (3-methylbut-2enyl) bicyclo (3.3.1) non-3-ene-2,9-dione or named bacanone wich is suspected as a new compound. From the isolation were also found of known volatile compounds b - caryophyllene, α-humulene and b-cadinene and stigmasterol. The test results of antioxidant activity of  n-hexane extract and pure compound  showed IC50 respectively 17.78 ppm and 12.79 ppm which comparison with  quercetin is 9.90 ppm. Key words :  Garcinia bancana Miq., antioxidant, DPPH, 3-(3,4-dihydroxybenzoil)-4-hidroxy-8-8-dimethyl-1,7-bis (3-methylbut-2enil)bisiklo(3.3.1)no-3-ene-2,9-dione, bacanone.

scholarly journals SYNTHESIS ALKANOLAMIDE TETRAHIDROXY OCTADECANOATE COMPOUND FROM CANDLE NUT OIL

2010 ◽  
Vol 9 (2) ◽  
pp. 271-277 ◽  
Author(s):  
Daniel Daniel
Keyword(s):  
Gas Chromatography ◽  
Fatty Acid ◽  
Methyl Ester ◽  
Column Chromatography ◽  
Acid Methyl Ester ◽  
Sodium Methylate ◽  
Nitrogen Gas ◽  
Acid Methyl ◽  
Ft Ir

Candle nut oil could be transesterificated by methanol with concentrated H2SO4 as a catalyst to form fatty acid methyl esther. Methyl linoleate could be separated by Column Chromatography mechanism technic partition from fatty acid methyl ester (FAME) mixture, then it was treated by ethanolamine at base condition in benzene as solvent and sodium methylate as a catalyst at reflux condition for 6 hours to form an alkanolamide. Alkanolamide could be epoxydized by tert-buthyl hydroperoxyde and peroxygenase as a catalyst and it was refluxed for 6 hours at 40 °C and nitrogen gas condition to form the epoxy alkanolamide octadecanoate, and then it was hydrolyzed by HCl 0.1 M to form alkanolamide tetrahidroxy octadecanoate (Polyol). Alkanolamide tetrahidroxy octadecanoate could be separated by Column Chromatography using silica gel H 40 and the eluent was the mixture of chloroform, ethyl acetate, formic acid in a ratio 90:10:1 (v/v/v/). Determination of HLB value from alknolamide tetrahydroxy octadecanoate is 13.096. Therefore, this compound was particularly suitable for application as an o/w emulsifiers. All af the reaction steps were confirmed by using FT-IR, 1H-NMR, GC-MS, Gas Chromatography and TLC.   Keywords: Esterification, Candle nut oil, Surfactant, Amidation, Polyol.

A molecularly imprinted polymer with flash column chromatography for the selective and continuous extraction of diphenyl amine

RSC Advances ◽  
2015 ◽  
Vol 5 (90) ◽  
pp. 73434-73443 ◽  
Author(s):  
Pankaj E. Hande ◽  
Asit B. Samui ◽  
Prashant S. Kulkarni
Keyword(s):  
Column Chromatography ◽  
Molecularly Imprinted Polymer ◽  
Selective Recognition ◽  
Imprinted Polymer ◽  
Continuous Extraction ◽  
Molecularly Imprinted ◽  
Flash Column Chromatography ◽  
Diphenyl Amine ◽  
Ammunition Waste

The aim of this study was to prepare MIP for the selective recognition of DPA and its combination with flash column chromatography for the continuous extraction of DPA from ammunition waste.

scholarly journals Preparation of (+)- and (−)- β-phenyl- and β-(4-chlorophenyl)-γ- butyrolactones: Key Intermediates in the Synthesis of β-phenyl-GABA and Baclofen

2017 ◽  
Vol 59 (1) ◽  
Author(s):  
Myriam Meléndez-Rodríguez
Keyword(s):  
Column Chromatography ◽  
Absolute Configuration ◽  
X Ray ◽  
Configuration Assignment ◽  
Subsequent Hydrolysis ◽  
Flash Column Chromatography ◽  
Crystallographic Structures ◽  
The Absolute ◽  
Hydrolysis Of

The preparation of b-phenyl- and  b-(4-chlorophenyl)-g-butyrolactones (<strong>±</strong>)<strong>-3</strong> and (<strong>±</strong>)<strong>-4</strong> and their resolution to the corresponding (+)-(<em>S</em>)-<strong>3</strong>, (-)-(<em>R</em>)-<strong>3</strong> and (+)-(<em>S</em>)-<strong>4, </strong>(<strong>-</strong>)-(<em>R</em>)-<strong>4</strong> through formation, flash column chromatography separation and subsequent hydrolysis of diastereoisomeric 4-hydroxybutyramides (2’<em>R</em>,3<em>S</em>)-<strong>5</strong>, (2’<em>R</em>,3<em>R</em>)-<strong>5</strong>, (2’<em>R</em>,3<em>S</em>)-<strong>6</strong> and (2’<em>R</em>,3<em>R</em>)-<strong>6</strong> is described. The absolute configuration assignment of enantiopure <strong>3</strong> and <strong>4</strong> was supported by X-ray crystallographic structures of (2’<em>R</em>,3<em>R</em>)-<strong>5</strong>,<strong> </strong>(2’<em>R</em>,3<em>S</em>)-<strong>6</strong> and (2’<em>R</em>,3<em>R</em>)-<strong>6</strong>.

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