On the Rate of the Acid-Catalyzedtrans-Esterification of Butyl Alcohol and Ethyl Acetate

1949 ◽  
Vol 71 (6) ◽  
pp. 1991-1994 ◽  
Author(s):  
L. Farkas ◽  
O. Schachter ◽  
B. H. Vromen
Keyword(s):  
Ethyl Acetate ◽  
Butyl Alcohol

HSCCC Separation of Three Main Compounds from the Crude Extract of Dracocephalum Tanguticum by Using Dimethyl Sulfoxide as Cosolvent

2020 ◽  
Author(s):  
Xue Yang ◽  
Yongling Liu ◽  
Tao Chen ◽  
Nana Wang ◽  
Hongmei Li ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Ethyl Acetate ◽  
Dimethyl Sulfoxide ◽  
Efficient Method ◽  
Crude Extract ◽  
High Speed ◽  
Glacial Acetic Acid ◽  
Butyl Alcohol ◽  
Preparative Hplc ◽  
Counter Current

Abstract Separation of natural compounds directly from the crude extract is a challenging work for traditional column chromatography. In the present study, an efficient method for separation of three main compounds from the crude extract of Dracocephalum tanguticum has been successfully established by high-speed counter-current chromatography (HSCCC). The crude extract was directly introduced into HSCCC by using dimethyl sulfoxide as cosolvent. Ethyl acetate/n-butyl alcohol/0.3% glacial acetic acid (4: 1: 5, v/v) system was used and three target compounds with purity higher than 80% were obtained. Preparative HPLC was used for further purification and three target compounds with purity higher than 98% were obtained. The compounds were identified as chlorogenic acid, pedaliin and pedaliin-6″-acetate.

Comparison on Antimicrobial Activity of Different Solvent Extracts from Aerial Stem and Rhizome of Douttuynia cordata

2013 ◽  
Vol 706-708 ◽  
pp. 44-47
Author(s):  
Shao Juan Jiang
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Activity ◽  
Bacillus Subtilis ◽  
Aspergillus Niger ◽  
Ethyl Acetate ◽  
Water Extract ◽  
Butyl Alcohol ◽  
Alcohol Extract ◽  
Houttuynia Cordata ◽  
Aerial Stem

The 95% of ethanol crude extract of aerial stem and rhizome of houttuynia cordata was sequentially extracted with petroleum ether, ethyl acetate, n-butyl alcohol and water. Antimicrobial activity and minimum inhibitory concentration (MIC) of the different extracts against Staphylococlus aureus, Escherichia coli, Bacillus subtilis, Aspergillus niger and Saccharomycetes were examined with filter paper method. And antimicrobial activity between aerial stem and rhizome was compared. The result showed that, among the extracts of aerial stem and rhizome of houttuynia cordata, with regard to antimicrobial activity, water extract was strongest against Staphylococlus aureus, and ethyl acetate extract was strongest against Escherichia coli, and n-butyl alcohol extract was strongest against Bacillus subtilis and Saccharomycetes, while each extract had no significant antimicrobial activity against Aspergillus niger. Moreover, the antimicrobial activity of rhizome was stronger than that of the aerial stem.

The transmission of polar effects. Part X. The esterification with diazodiphenyl-methane and the ionization of 9-substituted 10-anthroic and 8-substituted 1-naphthoic acids

1969 ◽  
Vol 47 (2) ◽  
pp. 185-190 ◽  
Author(s):  
Keith Bowden ◽  
D. C. Parkin
Keyword(s):  
Free Energy ◽  
Ethyl Acetate ◽  
Field Effect ◽  
Isopropyl Alcohol ◽  
Substituent Effects ◽  
Butyl Alcohol ◽  
Rate Coefficients ◽  
Linear Free Energy ◽  
Energy Relations ◽  
Substituted 1

The rate coefficients for the reaction with diazodiphenylmethane in methanol, ethanol, isopropyl alcohol, t-butyl alcohol, 2-methoxyethanol, 2-n-butoxyethanol, and ethyl acetate at 30° and the pKa values in 80% 2-n-butoxyethanol–water of a series of 9-substituted 10-anthroic and 8-substituted 1-naphthoic acids have been determined. The effect of substitution has been analyzed by linear free energy relations. The variation in the susceptibilities of the systems to polar substituent effects with the medium are examined. The occurrence of reversed dipolar substituent effects in the reactions of the 1,8-naphthoic acids is detected. The implications of the results for the inductive and field effect models for the transmission of polar effects are discussed.

The Antibacterial Activity of the Extracts of Apocynum Venetum and Apocynum Venetum Fiber

2011 ◽  
Vol 233-235 ◽  
pp. 2328-2331 ◽  
Author(s):  
Hui Juan Wang ◽  
Hao Chen ◽  
Guang Ting Han
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Bacillus Subtilis ◽  
Candida Albicans ◽  
Ethyl Acetate ◽  
Antibacterial Effect ◽  
Antibacterial Activities ◽  
Butyl Alcohol ◽  
Apocynum Venetum

In this study, the total flavone contents of Apocynum venetum extract and Apocynum venetum fiber extracts were evaluated. Their antibacterial activity was tested via testing the antibacterial effect of their aqueous, ethyl acetate and n-butyl alcohol extracts. The results were showed that both the materials extracts at the concentration of 100, 50mg/ml had significantly antibacterial activities against staphylococcus aureus, and had a few effect on bacillus subtilis, pseudomonadaceae, pseudomonas aeruginosa, staphylococcus epidermidis, escherichia coli and candida albicans.

scholarly journals Effect of tea root-derived proanthocyanidin fractions on protection of dentin collagen

2019 ◽  
Vol 48 (5) ◽  
pp. 030006051989130
Author(s):  
Honglin Yang ◽  
Bingqing Xie ◽  
Yue Wang ◽  
Yayun Cui ◽  
Hui Yang ◽  
...  
Keyword(s):  
Ethyl Acetate ◽  
Butyl Alcohol ◽  
Degree Of Polymerization ◽  
Cross Linking ◽  
Protective Mechanisms ◽  
Dentin Collagen ◽  
And Function ◽  
High Degree ◽  
Collagen Cross Linking

Objectives Proanthocyanidins (PAs) have been widely used as effective agents for dentin collagen cross-linking to enhance the biomechanics and biostability of dentin in vitro. However, the effects and protective mechanisms of various tea root-derived PA components on dentin remain undefined. This study evaluated the effects of these tea root-derived PA components on dentin biomechanics and biostability. Methods In this study, ethyl acetate and n-butyl alcohol were used to extract PAs with different degrees of polymerization from tea roots; the effects of these PA extracts on dentin were evaluated. Results Dentin was treated with glutaraldehyde, ethyl acetate, n-butyl alcohol, or water. PAs with a high degree of polymerization, extracted using n-butyl alcohol, were able to more effectively improve dentin collagen cross-linking, increase resistance to bacterial collagenase digestion, and enhance dentin elasticity, relative to treatment with glutaraldehyde or PAs with a low degree of polymerization (extracted using ethyl acetate). Additionally, treatment with aqueous extract of tea roots was detrimental to dentin stability and function. Conclusions PAs with a high degree of polymerization were effective for dentin protection and restoration in vitro, suggesting clinical treatment potential for tea root-derived PAs.

scholarly journals Comparative Studies of Different Extracts from Eucommia ulmoides Oliv. against Rheumatoid Arthritis in CIA Rats

2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Jian-Ying Wang ◽  
Xiao-Jun Chen ◽  
Lei Zhang ◽  
Ying-Yi Pan ◽  
Zu-Xi Gu ◽  
...  
Keyword(s):  
Ethyl Acetate ◽  
Structural Integrity ◽  
Joint Destruction ◽  
Ethanol Extract ◽  
Ethyl Acetate Fraction ◽  
Butyl Alcohol ◽  
Joint Surface ◽  
Control Group ◽  
Eucommia Ulmoides ◽  
Immune Inflammation

To compare efficacy of different extracts from Eucommia ulmoides Oliv. with both immune inflammation and joint destruction in collagen induced arthritis (CIA) rat model. Rats were divided into normal group (Nor), control group (CIA), TG group (treated with tripterygium glycoside), E70 group (treated with 70% ethanol extract from Eucommia ulmoides Oliv.), EA group (treated with ethyl acetate fraction from E70), and EN group (treated with n-butyl alcohol fraction from E70). All extracts from Eucommia ulmoides Oliv. could significantly inhibit ankle swelling, pathological manifestations, and cytokine levels in serum and spleen, by using foot volume measurement, H&E staining, ELISA, and RT-QPCR methods, respectively. All extracts could significantly inhibit rough joint surface and marginal osteophytes, improve RANKL/OPG ratio, and decrease MMP-9 expression, by using micro-CT and immunohistochemical staining. The activation of IKK/NF-κB signaling pathway was also inhibited by all extracts. In addition, ethyl acetate fraction from E70 presented better effect on RANKL/OPG system. This study identified effective extracts from Eucommia ulmoides Oliv. relieving immune inflammation and maintaining structural integrity of joints in CIA rats.

Iridoids from the stems of Viburnum erosum

Holzforschung ◽  
2014 ◽  
Vol 68 (7) ◽  
pp. 761-767 ◽  
Author(s):  
Seo-Ji In ◽  
Kyeong-Hwa Seo ◽  
Na-Young Song ◽  
Myoung-Chong Song ◽  
Eun-Mi An ◽  
...  
Keyword(s):  
Carboxylic Acid ◽  
Ethyl Acetate ◽  
Silica Gel ◽  
Column Chromatography ◽  
Spectroscopic Data ◽  
2D Nmr ◽  
Butyl Alcohol ◽  
Chemical Structures ◽  
Etoac Fraction ◽  
C Nmr

Abstract Two new iridoids were isolated and identified to three known ones, namely, loganic acid (2), sweroside (3), and 7-O-tigloylsecologanol (4), from the stems of Viburnum erosum. Dried stems of V. erosum were extracted with 80% methanol (MeOH), and the concentrated extract was partitioned successively with ethyl acetate (EtOAc), n-butyl alcohol (n-BuOH), and H2O. Five compounds were isolated after repeated silica gel (SiO2), octadecyl SiO2 (ODS), and Sephadex LH-20 column chromatography of the EtOAc fraction. The chemical structures of the compounds were determined based on spectroscopic data from 1H- and 13C-NMR, DEPT, and 2D-NMR (gCOSY, gHSQC, gHMBC) data. The new iridoids were identified as 3,7-dihydroxy-8-methyl-cyclopenta[c]pyran-4-carboxylic acid (1) and rel-(1S,5R,9S)-9-ethenyl-1-(β-D-glucopyrinosyloxy)-5,9-dihydro-5-{2-[(2-methylbut-2-enoyl)oxy]ethyl}-1H-pyran-4-carboxylic acid (5) and named viburnin and epi-7-O-tigloylsecologanolic acid, respectively. This is the first report of the isolation of these five iridoids from V. erosum.

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