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).

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 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.

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>.

scholarly journals ISOLATION AND IDENTIFICATION FLAVONOID COMPOUND FROM THE STEM BARK OF Saccopetalum horsfieldii BENN

2010 ◽  
Vol 6 (3) ◽  
pp. 312-315
Author(s):  
Mahmiah Mahmiah
Keyword(s):  
Melting Point ◽  
1H Nmr ◽  
Column Chromatography ◽  
Room Temperature ◽  
Stem Bark ◽  
Spectroscopy Method ◽  
Flavonoid Compound ◽  
Isolation And Identification ◽  
Vacuum Column ◽  
Flash Column Chromatography

Isolation and identification flavonoid compound from the stem bark of Indonesian plant Saccopetalum horsfieldii Benn. Annonaceae family have been done. Extraction was carried out by maseration method using methanol at room temperature, the product was then extracted by n-hexane and etil acetate. Etil acetate extract separation carried out by liquid vacuum column chromatography and flash column chromatography. The product purificated by recristalization using acetone p.a. into yellow solid that having melting point of 224-226 °C. The structure of flavonoid compound was determinated by spectroscopy method : UV-vis, IR, 1H-NMR and 12C-NMR. The flavonoid compound known as quercetin-3,7-dimetil eter or 3,7-dimetoksi quercetin.                                                                                                                                                       Keywords: Saccopetalum horsfieldii Benn, flavonoid, chromatography, quercetin

scholarly journals Isolation and Identification of Pure Bioactive Compounds from Cuscuta reflexa Grown on Nerium oleander Host Plant by Flash Column Chromatography and GC-MS/MS Analysis

2020 ◽  
Vol 32 (10) ◽  
pp. 2486-2488
Author(s):  
Pooja Saini ◽  
Ekta Menghani ◽  
Rekha Mithal
Keyword(s):  
Host Plant ◽  
Bioactive Compounds ◽  
Column Chromatography ◽  
Mobile Phase ◽  
Ethyl Acetate Extract ◽  
Nerium Oleander ◽  
Isolation And Identification ◽  
Cuscuta Reflexa ◽  
Flash Column Chromatography ◽  
Area Percentage

In this work, an ethyl acetate extract of Cuscuta reflexa grown on Nerium oleander host plant was used for the isolation and identification of pure bioactive compounds. Chloroform:methanol was used as mobile phase for flash column chromatography. Five pure bioactive compounds were isolated and two compounds were identified using GC-MS/MS technique. Glycerol-1-palmitate and squalene were identified in Cuscuta reflexa using NIST library on the basis of area percentage.

scholarly journals Supramolecular Chromatographic Separation of C60 and C70 Fullerenes: Flash Column Chromatography vs. High Pressure Liquid Chromatography

2021 ◽  
Vol 22 (11) ◽  
pp. 5726
Author(s):  
Subbareddy Mekapothula ◽  
A. D. Dinga Wonanke ◽  
Matthew A. Addicoat ◽  
David J. Boocock ◽  
John D. Wallis ◽  
...  
Keyword(s):  
High Pressure ◽  
Liquid Chromatography ◽  
Stationary Phase ◽  
High Pressure Liquid Chromatography ◽  
Column Chromatography ◽  
Stationary Phases ◽  
In Silico Studies ◽  
Flash Column Chromatography ◽  
New Stationary Phase ◽  
Fullerene Mixture

A silica-bound C-butylpyrogallol[4]arene chromatographic stationary phase was prepared and characterised by thermogravimetric analysis, scanning electron microscopy, NMR and mass spectrometry. The chromatographic performance was investigated by using C60 and C70 fullerenes in reverse phase mode via flash column and high-pressure liquid chromatography (HPLC). The resulting new stationary phase was observed to demonstrate size-selective molecular recognition as postulated from our in-silico studies. The silica-bound C-butylpyrogallol[4]arene flash and HPLC stationary phases were able to separate a C60- and C70-fullerene mixture more effectively than an RP-C18 stationary phase. The presence of toluene in the mobile phase plays a significant role in achieving symmetrical peaks in flash column chromatography.

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