scholarly journals On the Phenolic Hydroxyl Group of Lignosulfonic Acid and the Existence of Carboxyl Group in Lignosulfonic Acid

1956 ◽  
Vol 29 (1) ◽  
pp. 209-210 ◽  
Author(s):  
Hiroshi Mikawa ◽  
Koichiro Sato ◽  
Chizuko Takasaki ◽  
Kiyo Ebisawa
Keyword(s):  
Phenolic Hydroxyl ◽  
Hydroxyl Group ◽  
Carboxyl Group ◽  
Lignosulfonic Acid

The Influence of Anthraquinone in Sulfite Delignification of Norway Spruce. 2. Phenolic Hydroxyl Group Formation

Holzforschung ◽  
1994 ◽  
Vol 48 (s1) ◽  
pp. 140-145 ◽  
Author(s):  
Hsin-Tai Chen ◽  
Masamitsu Funaoka ◽  
Yuan-Zong Lai
Keyword(s):  
Norway Spruce ◽  
Group Formation ◽  
Phenolic Hydroxyl ◽  
Hydroxyl Group

Preparation of Water-Soluble Carboxymethylated Lignin from Wheat Straw Alkali Lignin

2012 ◽  
Vol 550-553 ◽  
pp. 1293-1298 ◽  
Author(s):  
Lin Huo Gan ◽  
Ming Song Zhou ◽  
Xue Qing Qiu
Keyword(s):  
Wheat Straw ◽  
Acid Concentration ◽  
1H Nmr Spectroscopy ◽  
Water Soluble ◽  
Monochloroacetic Acid ◽  
Hydroxyl Group ◽  
Carboxyl Group ◽  
Optimum Conditions ◽  
Alkali Lignin ◽  
Carboxyl Group Content

Water-soluble carboxymethylated lignin (CML) was synthesized using wheat straw alkali lignin (WAL) in aqueous medium. The process of carboxymethylation was optimized with respect to the NaOH concentration, monochloroacetic acid concentration, reaction temperature and time. The optimized product has a yield of 80.47% and a carboxyl group content of 2.8231 mmol•g-1, respectively. The optimum conditions for carboxymethylation are NaOH concentration of 20.0% (wt%), monochloroacetic acid concentration of 37.5% (wt%), temperature of 70 °C and time of 90 min. The optimized CML was characterized by FTIR spectroscopy, 1H NMR spectroscopy and interfacial tension apparatus. The result shows that the substitution reaction of carboxymethylation occurs simultaneously in the phenolic hydroxyl group and aliphatic hydroxyl group in WAL. CML has the surface activity in water for industrial application as dispersant.

Aqueous Medium Radical Addition to Ketimines with a Phenolic Hydroxyl Group

Synlett ◽  
2004 ◽  
Vol 2004 (14) ◽  
pp. 2597-2599 ◽  
Author(s):  
Yoshiji Takemoto ◽  
Hideto Miyabe ◽  
Yousuke Yamaoka
Keyword(s):  
Aqueous Medium ◽  
Radical Addition ◽  
Phenolic Hydroxyl ◽  
Hydroxyl Group

Methylation of Phenolic Hydroxyl Group and Demethylation of Anisoles

2009 ◽  
Vol 2009 (4) ◽  
pp. 229-230 ◽  
Author(s):  
Nobuhiro Sato ◽  
Hiroyuki Endo
Keyword(s):  
Microwave Heating ◽  
Room Temperature ◽  
Reverse Reaction ◽  
Phenolic Hydroxyl ◽  
Hydroxyl Group ◽  
Hydroxyl Groups ◽  
Phenolic Hydroxyl Groups ◽  
Phenyl Ethers ◽  
Methyl Phenyl

A mild methylation of phenolic hydroxyl groups with iodomethane was enabled in the presence of sodium bis(trimethylsilyl)amide at room temperature. The reverse reaction, namely demethylation of methyl phenyl ethers, was easily achieved by microwave heating with neat iodotrimethylsilane.

scholarly journals SYNTHESIS, IN VITRO ANTIOXIDANT AND ANTIMICROBIAL EVALUATION OF 3-HYDROXY CHROMONE DERIVATIVES

2018 ◽  
Vol 11 (3) ◽  
pp. 259
Author(s):  
Pallavi Kamble ◽  
Sailesh Wadher
Keyword(s):  
Antioxidant Activity ◽  
Double Bond ◽  
Antifungal Activity ◽  
Phenolic Hydroxyl ◽  
Hydroxyl Group ◽  
Antibacterial And Antifungal Activity ◽  
Activity Data ◽  
Group 4 ◽  
Antibacterial And Antifungal

 Objective: The objective of the present study was to synthesize a series of 3-hydroxychromone derivatives and to evaluate its in vitro antioxidant and antimicrobial activities.Methods: 3-hydroxy chromones were synthesized using an algar flynn oyamada method which includes oxidative cyclization of 2-hydroxy chalcones in basic solution by hydrogen peroxide. 2-hydroxy chalcones were synthesized by Claisen-Schmidt condensation of substituted 2-hydroxy acetophenones with substituted aromatic aldehydes using polyethylene glycol-400 as a recyclable solvent. The synthesized compounds were evaluated for in vitro antioxidant activity by 1,1-diphenyl-2-picrylhydrazyl radical scavenging assay. In addition, these compounds were also screened for in vitro antibacterial and antifungal activity by agar cup method and Poison plate method, respectively.Results: The structures of the synthesized compounds were characterized by infrared, 1H nuclear magnetic resonance and mass spectroscopy. The antioxidant activity data revealed that all the synthesized derivatives exhibited good activity due to the presence of phenolic hydroxyl group, 4-oxo group and 2,3-double bond. Further, the activity increased with the introduction of a more phenolic hydroxyl group and adjacent methoxy group in the structure. The antimicrobial activity data showed that the compounds possess better antibacterial and antifungal activity which is attributed to the presence of phenolic hydroxyl group and 4-oxo group in the structure.Conclusions: The use of inexpensive, eco-friendly and readily available reagents, easy work-up and high purity of products makes the procedure a convenient and robust method for the synthesis of title compounds. The presence of phenolic hydroxyl group, 4-oxo group, and 2,3-double bond in the structure is responsible for their good antioxidant and antimicrobial activities.

2-Substituted and 2,6-disubstituted 1,4-benzoquinone 4-oximes ('p-nitrosophenols')

1969 ◽  
Vol 22 (5) ◽  
pp. 935 ◽  
Author(s):  
RK Norris ◽  
S Sternhell
Keyword(s):  
Hydrogen Bonding ◽  
Physical Properties ◽  
Intramolecular Hydrogen Bonding ◽  
Tautomeric Equilibrium ◽  
Phenolic Hydroxyl ◽  
Hydroxyl Group ◽  
Electronic Effects ◽  
Intramolecular Hydrogen

The preparation and physical properties of 27 compounds in the title series are described. Tautomerism, syn-anti isomerism, N.M.R. parameters, and the mechanism of isomerization are discussed. In this series of derivatives, the tautomeric equilibrium in dioxan solutions lies heavily towards the oxime form unless intramolecular hydrogen bonding between the substituent at C2 (or C6) and the phenolic hydroxyl group of the nitroso form is possible. The substituents at C2 (and C6) influence the position of the syn-anti equilibrium in the quinone monoxime forms through electronic effects.

ChemInform Abstract: HASHISH, IMPORTANCE OF THE PHENOLIC HYDROXYL GROUP IN TETRAHYDROCANNABINOLS

1975 ◽  
Vol 6 (25) ◽  
pp. no-no
Author(s):  
D. B. ULISS ◽  
H. C. DALZELL ◽  
G. R. HANDRICK ◽  
J. F. HOWES ◽  
R. K. RAZDAN
Keyword(s):  
Phenolic Hydroxyl ◽  
Hydroxyl Group

In Vitro Effects of Estrogens on the Δ4-Reduction of Testosterone by Rat Prostate and Liver Preparations

1973 ◽  
Vol 51 (6) ◽  
pp. 735-740 ◽  
Author(s):  
D. K. H. Lee ◽  
J. C. Young ◽  
Y. Tamura ◽  
D. C. Patterson ◽  
C. E. Bird ◽  
...  
Keyword(s):  
Phenolic Hydroxyl ◽  
Hydroxyl Group ◽  
Inhibitory Effects ◽  
Steroid Nucleus ◽  
In Vitro Effects ◽  
Rat Prostate ◽  
Steroid Structure ◽  
Soluble Fractions

The inhibitory effects of six estrogens (estradiol, estriol, ethynylestradiol, mestranol, diethylstilbestrol, and chlorotrianisene) on testosterone Δ4-reduction were studied in rat prostate and liver preparations. In the prostate homogenates only those estrogens with a complete steroid structure and a free phenolic hydroxyl group at position 3 of the steroid nucleus inhibited testosterone 5α-reduction when present at 600 times the concentration of testosterone. The inhibition by estradiol was found to be competitive for prostate homogenate, microsomal, and nuclear preparations. In the liver preparations (homogenate, microsomal, and soluble fractions) all six estrogens inhibited significantly when present at the same concentration as testosterone; diethylstilbestrol and ethynylestradiol were the most effective ones.

ESCA Detection of Surface Carboxyl Group Concentration of Polyanhydrides

1995 ◽  
Vol 414 ◽  
Author(s):  
J.-X Ciwen ◽  
J. A. Gardella ◽  
C. A. Santos ◽  
E. Mathiowitz
Keyword(s):  
Ftir Spectroscopy ◽  
Diffuse Reflectance ◽  
Nitrogen Concentration ◽  
Hydroxyl Group ◽  
Carboxyl Group ◽  
Reflectance Ftir ◽  
Group Concentration ◽  
Good Agreement

AbstractWe present in this paper the surface derivatization of polyanhydrides with triethylamine for labeling the hydroxyl group. The reaction was verified with diffuse reflectance FTIR spectroscopy. Surface derivatization of poly(fumaric-co-sebacic)anhydride of 50:50 and 20:80 compositions was performed and ESCA measurements showed the surface nitrogen concentration in good agreement with stoichiometry values.

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