STUDIES ON LIGNIN AND RELATED COMPOUNDS: XVII. METHYLATION OF WILLSTÄTTER AND FREUDENBERG LIGNINS

1935 ◽  
Vol 13b (2) ◽  
pp. 78-87 ◽  
Author(s):  
Fritz Brauns ◽  
Harold Hibbert
Keyword(s):  
Molecular Weight ◽  
Hydrogen Chloride ◽  
Methyl Alcohol ◽  
Methoxyl Group ◽  
Oxide Ring ◽  
Phenol Derivatives ◽  
The Difference ◽  
Derivatives Of ◽  
Related Compounds

Both Willstätter and Freudenberg lignins when treated with diazomethane give methylated products containing one additional methoxyl group, calculated on the basis of a molecular weight of about 850 for native lignin. When heated with phenol in the presence of a small amount of hydrogen chloride, both diazomethane-methylated lignin derivatives are converted into soluble phenol lignin derivatives containing one more methoxyl group than the corresponding phenol derivatives prepared from original, untreated Willstätter and Freudenberg lignins. This higher methoxyl value is also shown by the former phenol lignins on acetylation. The diazomethane-methylated phenol lignin derivatives prepared from diazomethane-methylated Willstätter and Freudenberg lignins correspond with the diazomethane-methylated phenol lignin derivatives prepared from original Willstätter and Freudenberg lignins. Also the fully methylated derivatives prepared from the phenol diazomethane-methylated Willstätter and Freudenberg lignins correspond with those described previously (2). The difference in methoxyl value between the phenol derivatives obtained from Willstätter lignin and the corresponding derivatives from Freudenberg lignin of 0.8–2.1% may be due possibly to the presence in the Freudenberg lignin of a methylene oxide ring which is removed in the isolation of Willstätter lignin, thus giving rise to the higher methoxyl content in the methylated derivatives of the latter. The action of methyl alcohol on original, on diazomethane-premethylated, and on fully methylated Willstätter and Freudenberg lignins was also investigated.

Antimicrobial, physico-chemical properties of nitrogen-containing preparations of derivates of menthol, quinoline and phenol

2018 ◽  
Vol 22 (2) ◽  
pp. 267-271
Author(s):  
V.G. Paliy ◽  
I.G. Paliy ◽  
A.O. Dudar ◽  
D.V. Paliy ◽  
A. V. Kulyk
Keyword(s):  
Molecular Weight ◽  
Surface Tension ◽  
Melting Point ◽  
Inflammatory Diseases ◽  
Antimicrobial Properties ◽  
Gram Negative Bacteria ◽  
Antimicrobial Drugs ◽  
Gram Negative ◽  
Phenol Derivatives ◽  
Derivatives Of

Successful research by scientists of new synthetic substances of various chemical groups contributes to the broadening of the arsenal of antimicrobial drugs for the prevention and treatment of purulent-inflammatory diseases. Antimicrobial drugs, as a rule, suppress pathogenic, invasive, adhesive properties and reduce the resistance of microorganisms to antibiotics in pathogens of supportive inflammatory diseases; significantly increase the effectiveness of treatment of diseases of infectious origin. The purpose of the study was to study the physicochemical, antimicrobial properties of derivatives of menthol, phenol and quinoline. The results of the study of physicochemical, antimicrobial properties of six chemical compounds of menthol, quinoline, and phenol derivatives using the principle of complex research, in which physicochemical, microbiological methods were used, are presented. There was shown that quaternary ammonium compounds of the menthol derivatives were alike white powders with a molecular weight of 581–693, a melting point of 990 to 1850° C. The chemicals are soluble in water, ethanol. Quinoline preparations have a molecular weight of 687; 756, melting point 178–2000°C; dissolved in ethanol. Compounds of phenol had a molecular weight of 111, 112, a melting point of 1020, 1100°C was soluble in ethanol. It has been established that synthesized substances possess a wide spectrum of antimicrobial action on Gram-positive, Gram-negative bacteria, Candida albicans. In antibiotic resistant strains of Staphylococci no markers of resistance to drugs containing in the molecule menthol, phenol, quinoline were found. In complex physical and chemical systems, it was important to study the coefficient of surface tension of solutions of drugs, which was an important objective physical indicator of the molecular state of various drugs. Distilled water was used as a control. Experiments were performed according to a well-known technique. According to the results of the study, in the control the surface tension of water was it was found to be 55,70 dn/cm2. In an experiment with 0,1% solution of decamethoxin; the drug number 2 was 40,80 dn/cm2 and 38,20 dn/cm2. In derivatives of quinoline (DN, drug № 4), was 39,60 dn/cm2 and 34,50 dn/cm2. Solutions of phenol (preparations №5; №6) were characterized by surface tension 32,40–43,50 dn/cm2. Surface tension of solutions of preparations depended on their chemical structure. The antimicrobial properties of the preparations were determined on the museum and clinical strains of microorganisms, which had typical tynctorial, morphological, and cultural characteristics. For a complete biological characterization in strains of Staphylococci, the formation of coagulase enzymes, lecithovitellase, hemolysins, and mannitol fermentation in anaerobic conditions were studied. At 12 museum and clinical strains of bacteria, bacteriostatic and bactericidal effects of six drugs, which are derivatives of menthol (DK, №2), quinoline (DN, №4), phenol (preparations №5, №6), have been detected. Derivatives of menthol acted bactericidal to Staphylococci at doses of 0,48-3,9 μg/ml; Quinoline derivatives in the range of 7,8–15,6 μg/ml; derivatives of phenol 31,25–62,5 μg/ml, respectively. Staphylococci were highly resistant to phenol derivatives (31,25–62,5 μg/ml). Gram-negative bacteria exhibited high resistance to quinoline and phenol derivatives (250–500 μg/ml). Summing up the results of determining the antimicrobial action of antiseptics derivatives of menthol, quinoline, it should be emphasized that the drugs have high activity in relation to Staphylococci (0,24–7,8 μg/ml). Phenol derivatives have low bacteriostatic and bactericidal effects on Gram-negative bacteria (125–500 μg/ml), which limits their use in medicine.

STUDIES ON LIGNIN AND RELATED COMPOUNDS: XIX. ALKALI LIGNIN

1935 ◽  
Vol 13b (2) ◽  
pp. 103-113 ◽  
Author(s):  
H. Borden Marshall ◽  
Fritz Brauns ◽  
Harold Hibbert
Keyword(s):  
Sodium Hydroxide ◽  
Hydrogen Chloride ◽  
Dimethyl Sulphate ◽  
Analytical Data ◽  
Hydroxyl Groups ◽  
Empirical Formulas ◽  
Alkali Lignin ◽  
Phenol Derivatives ◽  
Related Compounds ◽  
Partially Methylated

Alkali lignin was prepared by the method of Mehta (6). It was separated into two fractions, termed Alkali Lignin A, insoluble in dioxane-ether, and Alkali Lignin B, soluble in dioxane-ether. Both compounds were acetylated, partially methylated with diazomethane and fully methylated using dimethyl sulphate and sodium hydroxide. Treatment of both alkali lignins with phenol, using hydrogen chloride as catalyst, yielded phenol condensation products. Phenol Alkali Lignin A was acetylated, partially methylated with diazomethane and completely methylated with dimethyl sulphate and sodium hydroxide. It was found that one mole of Alkali Lignin A reacted with two moles of phenol. Alkali Lignin B yielded two phenol derivatives, an ether-insoluble and an ether-soluble product, which differ in the number of attached phenol groups. p-Bromphenol and o-bromphenol were also shown to react with Alkali Lignin A giving lignin derivatives having identical methoxyl and bromine content. On treatment of Alkali Lignin A with anhydrous methyl alcohol and hydrogen chloride a product with a higher methoxyl content was obtained, indicating the presence of hydroxyl groups capable of methylation with this reagent. From the analytical data of the different compounds some theoretical conclusions are drawn, and empirical formulas derived.

Energy Approximation

2017 ◽  
Author(s):  
Philip Isett
Keyword(s):  
Main Lemma ◽  
The Other ◽  
Coarse Scale ◽  
Continuous Solutions ◽  
Material Derivative ◽  
Energy Variation ◽  
Energy Approximation ◽  
The Difference ◽  
Derivatives Of

This chapter presents the equations and calculations for energy approximation. It establishes the estimates (261) and (262) of the Main Lemma (10.1) for continuous solutions; these estimates state that we are able to accurately prescribe the energy that the correction adds to the solution, as well as bound the difference between the time derivatives of these two quantities. The chapter also introduces the proposition for prescribing energy, followed by the relevant computations. Each integral contributing to the other term can be estimated. Another proposition for estimating control over the rate of energy variation is given. Finally, the coarse scale material derivative is considered.

ANALISA KANDUNGAN BETA-GLUKAN LARUT AIR DAN LARUT ALKALI DARI TUBUH BUAH JAMUR TIRAM (Pleurotus ostreatus) DAN SHIITAKE (Lentinus edodes)

2013 ◽  
Vol 13 (3) ◽  
Author(s):  
Netty Widyastuti ◽  
Teguh Baruji ◽  
Henky Isnawan ◽  
Priyo Wahyudi ◽  
Donowati Donowati
Keyword(s):  
Molecular Structure ◽  
Molecular Weight ◽  
Immune System ◽  
Pleurotus Ostreatus ◽  
Water Soluble ◽  
Low Molecular Weight ◽  
Lentinus Edodes ◽  
Beta Glucan ◽  
Oyster Mushrooms ◽  
The Difference

Beta glucan is a polysaccharide compound, generally not soluble inwater and resistant to acid. Beta glucan is used as an immunomodulator (enhancing the immune system) in mammals is usually a beta-glucan soluble in water, easily absorbed and has a low molecular weight. Several example of beta-glucan such as cellulose (β-1 ,4-glucan), lentinan (β-1 0.6-glucan) and (β-1 ,3-glucan), pleuran (β-1, 6 and β-1 ,3-glucan) are isolated from species of fungi Basidiomycota include mushrooms (Pleurotus ostreatus) and shiitake (Lentinus edodes).The purpose of thisresearch activity is to obtain beta-glucan compound that can be dissolved in water and in alkali derived from fungi Basidiomycota, i.e, Oyster mushrooms (Pleurotus ostreatus) and shiitake (Lentinus edodes). The result of beta-glucan compared to characterize the resulting beta glucan that is molecular structure . The difference of beta glucan extraction is based on the differences in solubility of beta-glucan. Beta glucan could be water soluble and insoluble water.

Preparation of Chloro and Sulfanyl Derivatives of 1-(2-Deoxy-4-C-hydroxymethyl-α-L-threo-Pentofuranosyl)uracil

1997 ◽  
Vol 62 (7) ◽  
pp. 1114-1127 ◽  
Author(s):  
Hubert Hřebabecký ◽  
Jan Balzarini ◽  
Antonín Holý
Keyword(s):  
Nucleophilic Substitution ◽  
Hydrogen Chloride ◽  
Thionyl Chloride ◽  
Sodium Methoxide ◽  
Thioacetic Acid ◽  
Uracil Derivatives ◽  
Derivatives Of ◽  
Hiv 1

3'-Chloro and 3'-acetylsulfanyl derivatives of 1-(2-deoxy-4-C-hydroxymethyl-α-L-threo-pentofuranosyl)uracil were prepared by reaction of 2,3'-anhydro-1-{5'-O-benzoyl-4'-C-[(benzoyloxy)methyl]-2'-deoxy-α-L-erythro-pentofuranosyl}uracil (3) with hydrogen chloride and thioacetic acid, respectively. The reaction with hydrogen chloride gave a mixture of N-1 and N-3 substituted uracil derivatives 12 and 14. Reaction of 1-{3-O-benzoyl-4-C-[(benzoyloxy)methyl]-2-deoxy-α-L-threo-pentofuranosyl}uracil (7) with thionyl chloride and subsequent debenzoylation afforded 1-(4-C-chloromethyl-2-deoxy-β-D-erythro-pentofuranosyl)uracil (19). Nucleophilic substitution with lithium thioacetate, followed by deacylation, converted 1-{3-O-benzoyl-4-C-[(benzoyloxy)methyl]-2-deoxy-5-O-p-toluenesulfonyl-α-L-threo-pentofuranosyl}uracil (9) into 1-(2-deoxy-4-C-sulfanylmethyl-β-D-erythro-pentofuranosyl)uracil (21). The obtained thiols were oxidized with iodine or air to give 1,1'-[disulfandiylbis(2,3-dideoxy-4-hydroxymethyl-α-L-threo-pentofuranose-3,1-diyl]di(pyrimidine-2,4-(1H,3H)-dione) (17) and 1,1'-[disulfandiylbis(2,5-dideoxy-4-hydroxymethyl-α-L-threo-pentofuranose-5,1-diyl]di(pyrimidine-2,4(1H,3H)-dione) (22). Reaction of 1-{3-acetylsulfanyl-5-O-methanesulfonyl-4-C-[(benzoyloxy)methyl]-2,3-dideoxy-α-L-threo-pentofuranosyl)}uracil (24) with methanolic sodium methoxide afforded 1-(3,5-anhydro-2,3-dideoxy-4-C-hydroxymethyl-3-sulfanyl-α-L-threo-pentofuranosyl)uracil (25). The same reagent was used in the preparation of 1-(3,5-anhydro-2-deoxy-4-C-hydroxymethyl-α-L-threo-pentofuranosyl)uracil (26) from 1-{4-C-[(benzoyloxy)methyl]-2-deoxy-5-O-p-toluenesulfonyl-α-L-threo-pentofuranosyl}uracil (8). From the series of 4'-substituted 2'-deoxyuridine derivatives, synthesized in this study, solely the 4'-chloromethyl derivative 19 and the oxetane derivative 26 exhibited an appreciable activity against HIV-1 and HIV-2.

Synthesis of 5,7-dihydroxynaphthoquinone derivatives and their reactions with nucleophiles: Nitration of 2,3-dimethylnaphthalene and subsequent transformations

1976 ◽  
Vol 29 (10) ◽  
pp. 2247 ◽  
Author(s):  
HJ Banks ◽  
DW Cameron ◽  
MJ Crossley ◽  
EL Samuel
Keyword(s):  
Unusual Reaction ◽  
Nitro Derivatives ◽  
Reactions With Nucleophiles ◽  
Derivatives Of ◽  
Related Compounds ◽  
Benzenoid Ring

5,7-Dihydroxy-2,3-dimethyl-l,4-naphthoquinone (5) and related compounds have been synthesized. The quinone affords an accessible substrate for studying an unusual reaction with nucleophiles, which involves attack at the 8-position, i.e. at the benzenoid ring. An unsuccessful approach to (5) has led to tri- and tetra-nitro derivatives of 2,3-dimethylnaphthalene. Reduction of the former and subsequent conversions have given aminonaphthoquinone and perimidinone derivatives.

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