Paper ionophoresis of carbohydrates. I. Procedures and results for four electrolytes

1959 ◽  
Vol 12 (1) ◽  
pp. 65 ◽  
Author(s):  
JL Frahn ◽  
JA Mills

Details are given of procedures for effecting paper ionophoresis of polyhydroxy compounds in the electrolytes borax, sodium arsenite, basic lead acetate, and sodium hydroxide. and for detecting the compounds after ionophoresis. Rates of migration are reported for 96 compounds, including all pentose and hexose sugars, the common disaccharides, all sugar alcohols up to the heptitols, the cyclitols, a number of glycols, and several glycosides and other derivatives of carbohydrates. Some new or improved reagents have been developed for locating carbohydrates on paper strips under various conditions. Sodium arsenite and basic lead acetate are the most effective electrolytes for separating reducing sugars, basic lead acetate is the best for separating sugar alcohols, and borax is the best for simple glycols. Some success has been achieved in correlating the configurations of stereoisomers with their mobilities in paper ionophoresis.

1955 ◽  
Vol 33 (12) ◽  
pp. 1824-1828 ◽  
Author(s):  
H. F. Bauer ◽  
Carol Teed

Triose-reductone-C14 was obtained by treating D-glucose-1-C14 with sodium hydroxide in the presence of lead acetate at elevated temperatures. Carbon atoms four, five, and six, as well as carbon atoms one, two, and three, of the D-glucose molecule are shown to contribute to the triose-reductone yield. The formation of triose-reductone was found not to be accompanied by glycerol formation. Mechanisms for fragmentation of reducing sugars are discussed in the light of these findings.


2012 ◽  
Vol 21 (26) ◽  
pp. 200-207
Author(s):  
Jūratė Čirūnaitė

The most popular names among Jewish women in 16th century Lithuania were Simcha, Marjam, Anna, Debora. The names were most frequently recorded as diminutives (63.3%), with only 36.4% appearing in canonical forms. The smallest group comprises names formed using only anthroponyms that were derived from those of (male) family members (29.6%). 35.2% of the namings are recorded as mixed type. The same number of women are recorded using only names in the documents.Personal names are included in 70.4% of recorded women’s namings. Andronyms (anthroponyms formed from the spouse’s name) were found in 64.8% of all the records. 9.3% of women’s namings include anthroponyms formed using the spouse’s patronymic. Only 1.9% of namings had a female patronymic (the derivative of the suffix -owna/-ewna).One-member female namings prevail (59.3%). Two-member namings comprise 33.3%. Three members are found in 5.6% of the namings, while four-membered ones comprise 1.9%. The average length of the namings is 1.5 times that of the anthroponyms.Common words explaining anthroponyms were found in 68.5% of the namings. Common words related to religion prevail (51.4%). 29.7% of the common words characterize relationships or family status, and only 10.8% describe occupation, post or trade (vocation). Common words describing descent (social origin) comprise only 8.1% of all the women’s namings.Namings consisting only of anthroponyms of family members can be subdivided into the following subgroups: 1) derivatives of the suffix -owaja/-ewaja; 2) derivatives of the suffix ‑owaja/-ewaja; 3) derivatives of the suffix -owaja/-ewaja + the genitive of a male patronymic; 4) derivatives of the suffix -owaja/-ewaja + a male patronymic + the genitive of a male patronymic. Namings without anthroponyms consisting of family members included names and names with common words. Mixed namings consisted of: 1) a name + a derivative of the suffix -owaja/-ewaja; 2) a derivative of the suffix -owaja/-ewaja + the genitive of a male patronymic + a name; 3) a derivative of the suffix -owaja/-ewaja + the genitive of a male patronymic + a name + a female patronymic.The most popular type of naming is a recorded name.


1993 ◽  
Vol 48 (3-4) ◽  
pp. 326-333 ◽  
Author(s):  
Beate Nicolaus ◽  
Gerhard Sandmann ◽  
Peter Böger

Abstract Protoporphyrinogen oxidase, the last enzyme of the common tetrapyrrole biosynthetic pathway, is inhibited by several peroxidizing compounds resulting in accumulation of photodynamic tetrapyrroles, mainly protoporphyrin IX. The inhibition characteristics of two chemi­cally unrelated compounds were studied using membrane bound protoporphyrinogen oxidase from corn etioplasts. As shown by Lineweaver-Burk-analysis, the inhibition of enzyme activity by the diphenyl ether oxyfluorfen and the cyclic imide MCI 15 are competitive with respect to the substrate. The competitive interaction of protoporphyrinogen and the two chemically un­related inhibitors indicate a relative specificity of the binding site. The reversibility of oxyfluorfen inhibition was evaluated by dilution experiments and was shown to be independent of the presence of DTT. The analysis of structure-activity-relationship on protoporphyrinogen oxidase inhibition was investigated with para-substituted derivatives of phenyl-3,4,5,6-tetrahydro-phthalimides. The results obtained by QSAR -calculation yielded a good correlation of the inhibitory activity determined by the lipophilicity of the para-substituent. These data point to one binding region of the inhibitors within a lipophilic environment associated with the active center of the enzyme.


1967 ◽  
Vol 45 (3) ◽  
pp. 275-290 ◽  
Author(s):  
S. C. Williams ◽  
J. K. N. Jones

A study has been made of various methods available for the identification and separation of the methyl ethers of arabinose. Gas–liquid partition chromatography has been used to separate the acetylated glycosides and the acetylated alditols of the methyl ethers of arabinose. All of the methyl ethers of arabinopyranose and arabinofuranose have been separated by paper chromatography. Several spray reagents have been used to distinguish between those methyl ethers with similar rates of movement. Thin-layer chromatography has been used to separate the methyl glycosides, acetylated methyl glycosides, and glycitols of the methyl ethers of arabinose, as well as the methyl ethers of the reducing sugar. The optical rotations of the reducing sugars and of the methyl glycosides of the methyl ethers of arabinose provide information about the ring form and, in the case of the glycosides, about the anomer present. The rotations of the acetylated and unacetylated O-methyl arabinitols aid in the determination of the position of the methyl substitutents. In connection with this study, all of the mono-O-methyl and tri-O-methyl, and most of the di-O-methyl ethers of arabinose have been synthesized. New syntheses have been devised for 4-O-methyl and 2,3-di-O-methyl arabinose, and the other sugars have been synthesized by known or partially revised syntheses. During this work, previously unreported derivatives of these sugars have been prepared.


2013 ◽  
Vol 9 ◽  
pp. 1517-1525 ◽  
Author(s):  
Marta K Kurpet ◽  
Aleksandra Dąbrowska ◽  
Małgorzata M Jarosz ◽  
Katarzyna Kajewska-Kania ◽  
Nikodem Kuźnik ◽  
...  

A method for the synthesis of N-aryl-C-nitroazoles is presented. A coupling reaction between variously substituted arylboronic acids and 3(5)-nitro-1H-pyrazole catalyzed by copper salt has been carried out in methanol in the presence of sodium hydroxide to afford the desired N-aryl-C-nitroazoles in good yields. This synthetic route has also been successfully applied to obtain N-phenyl derivatives of 4-nitropyrazole, 2-nitroimidazole, 4(5)-nitroimidazole and 3-nitro-1,2,4-triazole.


1998 ◽  
Vol 124 (1) ◽  
pp. 104-110 ◽  
Author(s):  
J. Christian Gerdes ◽  
J. Karl Hedrick

The use of multiple surface sliding controllers for robust control of nonlinear systems with mismatched uncertainties has produced a number of impressive applications, but also raised a few theoretical questions. Among the latter are the use of numerical differencing to obtain derivatives of desired trajectories, robustness to uncertainties in the gain terms and the common practice of filtering desired trajectories for implementation. This paper seeks to address these issues through the concept of a Dynamic Surface Controller, in which filters form an integral part of the structure. This filtering removes the need for numerical differencing and guarantees a certain smoothness, enabling other assumptions of smoothness to be relaxed. In this paper, the Dynamic Surface Controller is coupled with a sequential design procedure that carves a system workspace out of the state space. Within this bounded region, bounded tracking performance can be rigorously guaranteed in the presence of uncertainties and constraints such as rate limits and saturation can be systematically avoided. The design of a Dynamic Surface Controller and the advantages of the workspace concept are demonstrated in the context of engine speed control.


1967 ◽  
Vol 102 (3) ◽  
pp. 815-824 ◽  
Author(s):  
J. C. Fletcher

1. A system of separation using buffered Celite columns is described that enables the pipsyl derivatives of most of the common amino acids to be separated. 2. The reaction of pipsyl chloride with several amino acids not included in previous studies has been investigated. In particular, knowledge of the acid-soluble pipsyl derivatives of arginine, histidine, lysine, tyrosine and cysteic acid has been extended. 3. Reproducible factors have been obtained that enable corrections to be applied for the breakdown of pipsylamino acids on acid hydrolysis. 4. The reaction of pipsyl chloride with peptides has been studied under various conditions. 5. The extent of the reaction between pipsyl chloride and insulin depends on the nature of the solvent-buffer system, and under the best conditions so far found is about 75% complete. 6. In an Appendix, the separation of pipsylamino acids by thin-layer chromatography is described.


1970 ◽  
Vol 48 (23) ◽  
pp. 3727-3732 ◽  
Author(s):  
R. T. Coutts ◽  
Sharon J. Matthias ◽  
E. Mah ◽  
N. J. Pound

Treatment of (3,4-dihydro-4-hydroxy-3-oxo-2H-1,4-benzothiazin-2-yl)acetic acid (1a) with sodium hydroxide yields the corresponding lactam, i.e. (3,4-dihydro-3-oxo-2H-1,4-benzothiazin-2-yl)acetic acid, together with the α,β-unsaturated acid, 3,4-dihydro-3-oxo-2H-1,4-benzothiazine-Δ2,α-acetic acid. The 6-methyl- and 6-bromo-derivatives of 1a behaved similarly when reacted with sodium hydroxide but when 3,4-dihydro-4-hydroxy-3-oxo-2H-1,4-benzothiazine was so treated a more complex reaction occurred.Methyl (6-bromo-3,4-dihydro-4-hydroxy-3-oxo-2H-1,4-benzothiazin-2-yl)acetate was also treated with hydrochloric acid. The two products isolated were (6-bromo-3,4-dihydro-3-oxo-2H-1,4-benzothiazin-2-yl)acetic acid and (6-bromo-7-chloro-3,4-dihydro-3-oxo-2H-1,4-benzothiazin-2-yl)acetic acid.The action of hydrochloric acid on 3,4-dihydro-4-hydroxy-7-methyl-3-oxo-2H-1,4-benzothiazine also gave two products. One was the corresponding lactam; the other was unexpected and has been tentatively identified as bis[2-(3,4-dihydro-7-methyl-3-oxo-2H-1,4-benzothiazine].


1982 ◽  
Vol 47 (11) ◽  
pp. 2961-2968 ◽  
Author(s):  
Hubert Hřebabecký ◽  
Josef Brokeš ◽  
Jiří Beránek

Anhydronucleoside Ia was prepared from chloroarabinofuranosylcytosine IIIc or from 2,2'-anhydro-1-(5-chloro-5-deoxy-β-D-arabinofuranosyl)cytosine by the action of a strongly basic ion exchanger. The anhydro derivative IIa was prepared from 2,2'-anhydro-1-(5-chloro-5-deoxy-β-D-arabinofuranosyl)uracil by treatment with aqueous solution of sodium hydroxide. The action of hydrogen bromide in dimethylformamide on 2',5'-anhydronucleosides Ia and IIa leads both to the cleavage of the anhydro bond under formation of the 5'-bromo derivatives IIIa and IVa and to the cleavage of nucleosidic bond. In case of the uracil derivative IIa, the α-arabinofuranosyl derivative V was also isolated after preceding acetylation. For unambiguous proof of the structure, an alternative synthesis of compound V was performed.


1986 ◽  
Vol 32 (3) ◽  
pp. 219-225 ◽  
Author(s):  
A. Bonhomme ◽  
G. Fonty ◽  
M. J. Foglietti ◽  
D. Robic ◽  
M. Weber

To determine the contribution of protozoal activity to cellulose degradation, we maintained the ciliate Polyplastron multivesiculatum free of extracellular and intracellular cellulolytic bacteria. Control experiments to verify the absence of such bacteria were performed on cellular extracts, on filtrates, and on ciliates before lyophilization. The enzymatic activity was determined by viscometry and by determining the amount of reducing sugars produced. The enzyme was found to be an endo-1, 4- β-glucanase. Polyplastron multivesiculatum which was maintained free of extracellular and intracellular bacteria degraded soluble derivatives of cellulose and slightly degraded native cellulose. The activity was not due to intracellular bacterial cellulase, as ingested bacteria were lysed and digested by proteolytic enzymes of the protozoan. In addition, when preparing the filtrate solutions, P. multivesiculatum was maintained in culture for 5 days with Streptococcus faecalis (a facultatively anaerobic, noncellulolytic bacterium). Isoelectric focusing and chromatofocusing of lyophilized P. multivesiculatum that was free of cellulolytic bacteria yielded three protein fractions that degrade carboxymethylcellulose and hydroxyethylcellulose. Chromatofocusing also revealed the presence of two protein fractions with β-glucosidase activity.


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