An unusual Wittig reaction with sugar derivatives: exclusive formation of a 4-deoxy analogue of α-galactosyl ceramide

RSC Advances ◽  
2014 ◽  
Vol 4 (50) ◽  
pp. 26524-26534 ◽  
Author(s):  
Ratnnadeep C. Sawant ◽  
Yu-Hsuan Lih ◽  
Shih-An Yang ◽  
Chun-Hong Yeh ◽  
Hung-Ju Tai ◽  
...  
Keyword(s):  
Wittig Reaction ◽  
Reducing Sugars ◽  
Unexpected Formation ◽  
Galactosyl Ceramide ◽  
Sugar Derivatives

The Wittig reaction of reducing sugars undergoes an unexpected formation of dienes in the presence of base t-BuOK.

ChemInform Abstract: An Unusual Wittig Reaction with Sugar Derivatives: Exclusive Formation of a 4-Deoxy Analogue of α-Galactosyl Ceramide.

ChemInform ◽  
2015 ◽  
Vol 46 (4) ◽  
pp. no-no
Author(s):  
Ratnnadeep C. Sawant ◽  
Yu-Hsuan Lih ◽  
Shih-An Yang ◽  
Chun-Hong Yeh ◽  
Hung-Ju Tai ◽  
...  
Keyword(s):  
Wittig Reaction ◽  
Galactosyl Ceramide ◽  
Sugar Derivatives

Sugar-Amine Interactions in the Blood Clotting System and their Effects on Haemostasis

1975 ◽  
Author(s):  
L. Mester ◽  
B. Kraska ◽  
J. Crisba ◽  
M. Mester
Keyword(s):  
Blood Clotting ◽  
Reducing Sugars ◽  
Biological Properties ◽  
Blood Clotting System ◽  
Amino Groups ◽  
Clotting System ◽  
Enzymic Browning ◽  
Sugar Derivatives ◽  
Amadori Compounds

N-Glycosides and l-Desoxy-l-amino-2-keto-sugar derivatives (Amadori compounds) are formed from reducing sugars and amino groups of amino acids, proteins or simple amines in the first step of the Maillard reaction leading to the non enzymic browning of foodstuffs. Very little if any attention has been devoted to this reaction in the blood clotting system. Two examples are given to illustrate the possible role of this reaction in haemostasis.Poly-L-lysine, often considered as a model for collagen, reacts easily with D-glucose or D-galactose to form Amadori compounds with the ε-amino group of poly-L-lysine (mol. w. from 2,000 to 30,000). As a consequence, poly-L-lysine looses its ability to aggregate platelets. Serotonin reacts with D-glucose to form a stable and strongly reducing Amadori type compound. No change in the platelet aggregating ability of this compound has been observed, but other biological properties of the amine are highly affected.

QUALITATIVE AND QUANTITATIVE PHYTOCHEMICAL SCREENING AND IN VITRO ANTIOXIDANT EVALUATION OF PERGULARIA DAEMIA

2018 ◽  
Vol 24 (2) ◽  
Author(s):  
GITA MISHRA ◽  
HEMESHWER KUMAR CHANDRA ◽  
NISHA SAHU ◽  
SATENDRA KUMAR NIRALA ◽  
MONIKA BHADAURIA
Keyword(s):  
Reducing Sugars ◽  
Antioxidant Properties ◽  
Phytochemical Analysis ◽  
Phytochemical Screening ◽  
Qualitative And Quantitative ◽  
The Family ◽  
Ethanolic Extracts ◽  
Antioxidant Evaluation ◽  
In Vitro Antioxidant Activity

Pergularia daemia belongs to the family Asclepiadaceae, known to have anticancer, anti-inflammatory activity. Aim of the present study was to evaluate qualitative and quantitative phytochemical and antioxidant properties of ethanolic extracts of leaf, stem and root parts of P. daemia . Preliminary phytochemical analysis and in vitro antioxidant properties were evaluated by standard methods. The qualitative phytochemical analysis of P. daemia showed presence of flavonoids, tannins, alkaloid, phytosterol, carbohydrate, phenol, saponin, glycosides, terpenoids, steroids proteins and reducing sugars. Quantitative analysis showed polyphenol, flavonoid, flavonone, flavone and flavonol in P. daemia leaves, stem and root in considerable quantity. The in vitro antioxidant activity of P. daemia clearly demonstrated that leaf, stem and root parts have prominent antioxidant properties and was effective in scavenging free radicals.

Effects Attributed to Maleic Hydrazide when used for Chemical Sucker Control on Bright Tobacco

1980 ◽  
Vol 10 (2) ◽  
Author(s):  
Heinz Seltmann
Keyword(s):  
Statistical Difference ◽  
Reducing Sugars ◽  
Maleic Hydrazide ◽  
Water Soluble ◽  
Total Volatile ◽  
Total Alkaloids ◽  
Group I ◽  
Excellent Control ◽  
Per Se ◽  
Group Ii

AbstractThe effect of maleic hydrazide (MH) per se on bright tobacco was determined by comparing plants treated with MH to those without MH under conditions of good chemical sucker control. Sequential applications of each of five contact-type agents with MH one week later (Group I) were compared to dual applications of each of the same contact agents (Group II). In Group II suckers missed during applications were individually wetted to ensure excellent control. Sucker control was measured as 95 % for Group I and assumed to be 99 % for Group II. There were no agronomic differences between Groups I and II. In the visual warehouse appraisal, there was only a statistical difference for thin-bodied tobaccos between the two groups and a trend for slightly more heavy-bodied tobaccos in Group I. The chemical and physical analyses showed that filling value at 13 % moisture and equilibrium moisture content (EMC) measured at 60 % relative humidity were significantly lower in Group I than Group II. The result for EMC was questioned. Actual values for total alkaloids, total volatile bases minus nicotine, total ash, and alkalinity number of water-soluble ash were lower and reducing sugars were higher where MH was used. Except for EMC, the findings in this study reflected those established in studies where MH-treated and normally hand-suckered tobaccos were compared, but the differences here were generally not as great.

Double Ring-Closing Approach for the Synthesis of 2,3,6,7-Substituted Anthracene Derivatives

2020 ◽  
Author(s):  
Birgit Meindl ◽  
Katharina Pfennigbauer ◽  
Berthold Stöger ◽  
Martin Heeney ◽  
Florian Glöcklhofer
Keyword(s):  
Wittig Reaction ◽  
Condensation Reaction ◽  
Synthetic Methods ◽  
Anthracene Derivative ◽  
Double Ring ◽  
Mild Conditions ◽  
Wide Range ◽  
Anthracene Derivatives

Anthracene derivatives have been used for a wide range of applications and many different synthetic methods for their preparation have been developed. However, despite continued synthetic efforts, introducing substituents in some positions has remained difficult. Here we present a method for the synthesis of 2,3,6,7-substituted anthracene derivatives, one of the most challenging anthracene substitution patterns to obtain. The method is exemplified by the preparation of 2,3,6,7-anthracenetetracarbonitrile and employs a newly developed, stable protected 1,2,4,5-benzenetetracarbaldehyde as the precursor. The precursor can be obtained in two scalable synthetic steps from 2,5-dibromoterephthalaldehyde and is converted into the anthracene derivative by a double intermolecular Wittig reaction under very mild conditions followed by a deprotection and intramolecular double ring-closing condensation reaction. Further modification of the precursor is expected to enable the introduction of additional substituents in other positions and may even enable the synthesis of fully substituted anthracene derivatives by the presented approach.<br>

PHYSICOCHEMICAL AND MICROBIOLOGICAL EVALUATION OF HONEYS CONSUMED BY THE ELDERLY

2020 ◽  
Vol 5 ◽  
Author(s):  
Lusmarina Rodrigues Silva ◽  
Aline Marques Monte ◽  
Rafael Gomes Abreu Bacelar ◽  
Guilherme Antonio Silva Ribeiro ◽  
Aline Maria Dourado Rodrigues ◽  
...  
Keyword(s):  
Health Center ◽  
Reducing Sugars ◽  
The Elderly ◽  
Indicator Bacteria ◽  
Foreign Matter ◽  
Total Sugars ◽  
Significant Contamination ◽  
Almost All ◽  
Microbiological Analyses ◽  
Current Standards

Objective: to analyze physicochemical, microbiological and dirt parameters in marketed honeys, consumed by the elderly cared for at Integrated Health Center in Teresina, Piauí, Brazil. Method: the following analyses were performed: color, water activity, humidity, ash, pH, acidity, reducing sugars, total sugars, apparent sucrose and insoluble solids. Contamination indicator bacteria, mesophilic microorganisms, filamentous fungi and yeasts, as well as dirt and foreign matter, performed in the period from April to June 2016. Results: analyses of ash, pH, acidity and insoluble solids were outside current standards. Microbiological analyses did not present significant contamination. Also, analyses of dirt showed insect fragments, foreign matter in almost all the samples. Conclusion: parameters of ash, pH, acidity and insoluble solids, as well as dirt and foreign matter, indicated that the samples were not in accordance with current legislation. 

Extraction of Liberated Reducing Sugars from Rapeseed Cake via Acid and Alkali Treatments

2011 ◽  
Vol 40 (11) ◽  
pp. 1575-1581 ◽  
Author(s):  
Han-Seob Jeong ◽  
Ho-Yong Kim ◽  
Sye-Hee Ahn ◽  
Sei-Chang Oh ◽  
In Yang ◽  
...  
Keyword(s):  
Reducing Sugars ◽  
Rapeseed Cake
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