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Synthesis Of Glucose Pentaacetate Mechanism

Alpha D Glucose Pentaacetate Synthesis

Alpha D Glucose Pentaacetate Synthesis

Preparation Products And Raw materials: Raw materials. Suppliers. Related Search: Copyright 2016 ChemicalBook. All rights reserved. , beta-D-Glucose pentaacetate SDS CAS Number 604-69-3. Empirical Formula (Hill Notation) C 16 H. 20/D +4.2, c = 1 in chloroform. Chemical Synthesis. Alpha - and Beta - D - Glucose Pentaacetate. Pearson, Wesley A.; Spessard, Gary O. Journal of Chemical Education, 52, 12, 814-815, Dec 75. Descriptors: Chemistry. Beta-D-Glucose pentaacetate; 604-69-3; Penta-O-acetyl-beta-D-glucopyranose; 1,2,3,4,6-Penta-O-acetyl-b-D-glucopyranose; 1,2,3,4,6-Penta-O-acetyl-beta-D-glucopyranose;. THE MECHANISMS OF GLUCOSE PENTAACETATE ANOMERIZATION. step in the beta to alpha rearrangement of glucose pentaacetate. THE MECHANISMS OF GLUCOSE PENTAACETATE. Carbohydrate Derivative; Diacetone-D-Glucose;. Alpha-D-Glucose Pentaacetate. -D-glucose pentaacetate is white crystalline powder. -D(+)-Glucose pentaacetate for your research needs. []20/D +98. Chemical Synthesis. -D-Glucopyranose, pentaacetate. Formula: C 16 H 22 O 11;. Pentaacetyl--D-glucose; D--Glucose pentaacetate; D-alpha-glucose pentaacetate; Alpha-d-glucose. -D-Glucopyranose pentaacetate. Formula. alpha,d-,pentaacetate;. pentaacetate, -D-; -D-Glucose pentaacetate;. -D-(+)-Glucose pen taacetate. -D-Glucopyranose, pentaacetate. More. Validated by. and respiratory tract Alfa Aesar B22137. Continue reading >>

Mechanism Of Amino Acid-induced Skeletal Muscle Insulin Resistance In Humans

Mechanism Of Amino Acid-induced Skeletal Muscle Insulin Resistance In Humans

Plasma concentrations of amino acids are frequently elevated in insulin-resistant states, and a protein-enriched diet can impair glucose metabolism. This study examined effects of short-term plasma amino acid (AA) elevation on whole-body glucose disposal and cellular insulin action in skeletal muscle. Seven healthy men were studied for 5.5 h during euglycemic (5.5 mmol/l), hyperinsulinemic (430 pmol/l), fasting glucagon (65 ng/l), and growth hormone (0.4 μg/l) somatostatin clamp tests in the presence of low (∼1.6 mmol/l) and increased (∼4.6 mmol/l) plasma AA concentrations. Glucose turnover was measured with d-[6,6-2H2]glucose. Intramuscular concentrations of glycogen and glucose-6-phosphate (G6P) were monitored using 13C and 31P nuclear magnetic resonance spectroscopy, respectively. A ∼2.1-fold elevation of plasma AAs reduced whole-body glucose disposal by 25% (P < 0.01). Rates of muscle glycogen synthesis decreased by 64% (180–315 min, 24 ± 3; control, 67 ± 10 μmol · l−1 · min−1; P < 0.01), which was accompanied by a reduction in G6P starting at 130 min (ΔG6P260–300 min, 18 ± 19; control, 103 ± 33 μmol/l; P < 0.05). In conclusion, plasma amino acid elevation induces skeletal muscle insulin resistance in humans by inhibition of glucose transport/phosphorylation, resulting in marked reduction of glycogen synthesis. Plasma concentrations of alanine and particularly branched-chain amino acids (AAs) are elevated in insulin-resistant states such as obesity (1,2), and high dietary protein intake impairs glucose metabolism mainly by changing the utilization of gluconeogenic precursors (3–6). The mechanisms by which AAs could reduce skeletal muscle glucose uptake are as yet unclear. At the cellular level, availability of substrates for energy producti Continue reading >>

Thio--d-glucosides: Synthesis And Evaluation As Glycosidase Inhibitors And Activators

Thio--d-glucosides: Synthesis And Evaluation As Glycosidase Inhibitors And Activators

International Journal of Carbohydrate Chemistry Volume2014(2014), Article ID941059, 8 pages Thio--D-glucosides: Synthesis and Evaluation as Glycosidase Inhibitors and Activators Department of Chemistry, University of the Pacific, Stockton, CA 95211, USA Received 4 June 2014; Revised 1 August 2014; Accepted 2 August 2014; Published 21 August 2014 Copyright 2014 Andrey V. Samoshin et al. This is an open access article distributed under the Creative Commons Attribution License , which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Structurally simple 1-thio--D-glucopyranosides were synthesized and tested as potential inhibitors toward several fungal glycosidases from Aspergillus oryzae and Penicillium canescens. Significant selective inhibition was observed for - and -glucosidases, while a weak to moderate activation for - and -galactosidases. Thioglycosides are the hydrolysis- and metabolism-resistant synthetic S-analogs of natural O-glycosides. They attracted recently a rapidly increasing attention as competitive inhibitors of glycosidases and other enzymes involved in a variety of biochemical processes [ 1 , 2 ] related in particular to metabolic disorders and diseases, such as diabetes [ 1 , 3 ], to inflammations [ 2 , 4 ] and viral or bacterial infections [ 5 17 ], including tuberculosis [ 9 , 10 ], and to cancer [ 2 , 18 20 ]. However, surprisingly little is known about the inhibition of glucosidases by 1-thio--D-glucosides so far [ 21 24 ] (see the discussion). In a search for simple, readily accessible, and efficient glycosidase inhibitors [ 25 27 ], we designed, prepared, and assayed a series of structurally simple 1-thio--D-glucosides. 2.1. Synthesis of 1-Thio--D-glucopyranosides A series of Continue reading >>

An Error Occurred Setting Your User Cookie

An Error Occurred Setting Your User Cookie

An Error Occurred Setting Your User Cookie This site uses cookies to improve performance. If your browser does not accept cookies, you cannot view this site. There are many reasons why a cookie could not be set correctly. Below are the most common reasons: You have cookies disabled in your browser. You need to reset your browser to accept cookies or to ask you if you want to accept cookies. Your browser asks you whether you want to accept cookies and you declined. To accept cookies from this site, use the Back button and accept the cookie. Your browser does not support cookies. Try a different browser if you suspect this. The date on your computer is in the past. If your computer's clock shows a date before 1 Jan 1970, the browser will automatically forget the cookie. To fix this, set the correct time and date on your computer. You have installed an application that monitors or blocks cookies from being set. You must disable the application while logging in or check with your system administrator. This site uses cookies to improve performance by remembering that you are logged in when you go from page to page. To provide access without cookies would require the site to create a new session for every page you visit, which slows the system down to an unacceptable level. This site stores nothing other than an automatically generated session ID in the cookie; no other information is captured. In general, only the information that you provide, or the choices you make while visiting a web site, can be stored in a cookie. For example, the site cannot determine your email name unless you choose to type it. Allowing a website to create a cookie does not give that or any other site access to the rest of your computer, and only the site that created the cookie can read it. Continue reading >>

Mechanism By Which Metformin Reduces Glucose Production In Type 2 Diabetes

Mechanism By Which Metformin Reduces Glucose Production In Type 2 Diabetes

To examine the mechanism by which metformin lowers endogenous glucose production in type 2 diabetic patients, we studied seven type 2 diabetic subjects, with fasting hyperglycemia (15.5 +/- 1.3 mmol/l), before and after 3 months of metformin treatment. Seven healthy subjects, matched for sex, age, and BMI, served as control subjects. Rates of net hepatic glycogenolysis, estimated by 13C nuclear magnetic resonance spectroscopy, were combined with estimates of contributions to glucose production of gluconeogenesis and glycogenolysis, measured by labeling of blood glucose by 2H from ingested 2H2O. Glucose production was measured using [6,6-2H2]glucose. The rate of glucose production was twice as high in the diabetic subjects as in control subjects (0.70 +/- 0.05 vs. 0.36 +/- 0.03 mmol x m(-2) min(-1), P < 0.0001). Metformin reduced that rate by 24% (to 0.53 +/- 0.03 mmol x m(-2) x min(-1), P = 0.0009) and fasting plasma glucose concentration by 30% (to 10.8 +/- 0.9 mmol/l, P = 0.0002). The rate of gluconeogenesis was three times higher in the diabetic subjects than in the control subjects (0.59 +/- 0.03 vs. 0.18 +/- 0.03 mmol x m(-2) min(-1) and metformin reduced that rate by 36% (to 0.38 +/- 0.03 mmol x m(-2) x min(-1), P = 0.01). By the 2H2O method, there was a twofold increase in rates of gluconeogenesis in diabetic subjects (0.42 +/- 0.04 mmol m(-2) x min(-1), which decreased by 33% after metformin treatment (0.28 +/- 0.03 mmol x m(-2) x min(-1), P = 0.0002). There was no glycogen cycling in the control subjects, but in the diabetic subjects, glycogen cycling contributed to 25% of glucose production and explains the differences between the two methods used. In conclusion, patients with poorly controlled type 2 diabetes have increased rates of endogenous glucose produc Continue reading >>

Sugar Anomers - Organic Chemistry Message Board

Sugar Anomers - Organic Chemistry Message Board

General Posting Board. For general posting questions related to organic chemistry. I have some questions regarding the interconversions between sugar anomers using specific catalysts 1. When we use N-methyl imidazole to convert glucose into the pentaacetate glucose which anomer do we get? I have NMR data as well as melting point data for this but am confused because the NMR seems to relate with the Beta-D-Glucose anomer because of the higher coupling constant at C-2, whereas the melting point (~105 C) seems to reflect the alpha anomer. I understand that the melting point could just be incorrect but is there any reasoning (mechanics) to why the catalyst would give one anomer over another? 2. Why is acetic anhydride a much more reactive acetylating reagent then acetic acid? I have posted a reply at www.curvedarrow.com under acetylation of glucose. May I ask what level or class this experiment is for? Disclaimer, I am the author of the material found at Curved Arrow Press and curvedarrow.com . If you wish to leave me a comment, please find a link at Contact Curved Arrow Press Q) suggest a reason why zinc chloride catalyzes inter-conversion of the alpha and beta-anomers of glucose penta-acetate, but sodium acetate does not. i was thinking that sodium acetate is more bulkier and thus is not able to convert the alpha version of the anomers whereas the zinc chloride is more compact or ionic and thus is able to convert it. Does this make sense? No they are different mechanisms. Sodium acetate is a nucleophile. If you go to my blog ( ) and read the Nick Kim cartoon entry, that is the background. Since sodium is not attracted to electrons, the acetate is free to attack something else. In the case of the penta-acetate, acetate anion is too basic to be a leaving group in the prese Continue reading >>

Carbohydrates

Carbohydrates

Carbohydrates are the most abundant class of organic compounds found in living organisms. They originate as products of photosynthesis, an endothermic reductive condensation of carbon dioxide requiring light energy and the pigment chlorophyll. As noted here, the formulas of many carbohydrates can be written as carbon hydrates, Cn(H2O)n, hence their name. The carbohydrates are a major source of metabolic energy, both for plants and for animals that depend on plants for food. Aside from the sugars and starches that meet this vital nutritional role, carbohydrates also serve as a structural material (cellulose), a component of the energy transport compound ATP , recognition sites on cell surfaces, and one of three essential components of DNA and RNA. Carbohydrates are called saccharides or, if they are relatively small, sugars. Several classifications of carbohydrates have proven useful, and are outlined in the following table. sugars having an aldehyde function or an acetal equivalent. sugars having a ketone function or an acetal equivalent. sugars oxidized by Tollens' reagent (or Benedict's or Fehling's reagents). sugars not oxidized by Tollens' or other reagents. Carbohydrates have been given non-systematic names, although the suffix ose is generally used. The most common carbohydrate is glucose (C6H12O6). Applying the terms defined above, glucose is a monosaccharide, an aldohexose (note that the function and size classifications are combined in one word) and a reducing sugar. The general structure of glucose and many other aldohexoses was established by simple chemical reactions. The following diagram illustrates the kind of evidence considered, although some of the reagents shown here are different from those used by the original scientists. Hot hydriodic acid (HI) wa Continue reading >>

2009 03 05 Glucose Anomers

2009 03 05 Glucose Anomers

Two types of glucose anomerisation, via neutral and acidic conditions. Yielding both alpha- and beta-glucose pentaacetate. Copyright: Attribution Non-Commercial (BY-NC) Synthesis of - and -glucose pentaacetates Vaardigheden, Hogeschool UtrechtWouter Nieuwstraten, [email protected]: 2009-03-05 Two glucose pentaacetate anomers are synthesized using two separate catalysts and acetic anhydride withglucose. Iodine and sodium respectively yield - and -glucose pentaacetate. Glucose exists in equilibrium of two differentanomers; - and -glucose. The differencebetween these two stereo isomers is the locationof the hydroxyl group on the C -atom. Thisequilibrium is pH dependant and described in Scheme 1 .According to the citations used, the -glucose isformed in acidic solution, while the -glucose isformed in basic solution. In neutral pH, theglucose prefers to be in the -state. This statehas less hindrance since all hydroxyl groups arein equatorial position. In the -state, the C -hy-droxyl exists in axial position, which is less fa-vorable due to some steric hindrance from theC Scheme 1: Acid-Base equilibrium of - and -glucoseanomers The different anomers form because of anomer-ization; the hemiacetal bond (C ) breaks open toform the aldehyde (and alcohol). The aldehydewill close the ring to form the hemiacetal again.Depending on the conditions, the hydroxylgroup on the hemiacetal will form the - or -anomer.When glucose is reacted with acetic anhydrideand a catalyst the pentaacetate forms. Depend-ing on the type of catalyst used in the reaction,either - or -glucose pentaacetate is synthes-ized. The acetic anhydride reacts with the hy-droxyl groups in a general ester reaction( Scheme 2 ). Scheme 2: Mechanism of esterification with acetic anhyd-ride Hypothesized is that the s Continue reading >>

Chemistry - 3222 Palabras | Cram

Chemistry - 3222 Palabras | Cram

Synthesis, Recrystallization of -D-Glucose Pentaacetate from its Original D-Glucose and it comparison with literature though Melting point, TLC, IR, 1H and 13C NMR The synthesis of the product: -D-glucose pentaacetate is done though the acetylation using acetic anhydride with D-glucose with the help of sodium acetate. The recrystallization of the product is done though a polar solvent like water. The Result of this experiment has a percentage yield of 61% and analytical methods that are to detect the products are 1H NMR, 13 C NMR, COSY, FTIR (IR), Thin Layer Chromatography (TLC) and Melting point. There are only several compounds and molecules that are essential to the human body. Such molecule show more content This pathway is less stable as the catalyst of the reaction: acetic anhydride carbonyl oxygen is basic and be stabilized by the ionization of sodium acetate that allows the attack on the anomeric acetoxy group rather than a rotation of the anomeric carbon. The adding of the acyl group gives one to a more resonance stabilized glucose pentaacetate 3.In the formation of -d-glucose pentaacetate within this experiment, the goal is to yield as much of the selected theoretical product as much as possible and analyzed though 3 techniques: NMR, FTIR and TLC. Figure 1. Schematic Diagram of the reaction scheme between the Reactants: D-glucose, sodium acetate and acetic anhydride to the product: -D-glucose pentaacetate. (1) general anomerization of both d-glucose anomers, (2) mechanism of conversion from to -d-glucose. (3) acetylation from d-glucose to-d-glucose pentaacetate Figure 2. 1H and 13C NMR Labeling of -D-Glucose Pentaacetate. Table 1. Summary data showing 1H, COSY and 13C NMR data of -D-glucose Pentaacetate Based on Figure 2 Continue reading >>

Synthetic Methods Of -d-glucose Pentaacetate

Synthetic Methods Of -d-glucose Pentaacetate

Synthetic Methods of -D-Glucose Pentaacetate Author(s): Gangliang Huang , Chemistry, Chongqing Normal University, Chongqing, 401331, China. Qilin Tang , Delin Li , Ying Huang , Dan Zhang . Research on the synthesis of -D-glucose pentaacetate 2 was investigated. In particular, various methodsutilized for the synthesis of compound 2 were described in detail. Among them, acid catalysts including protonicacid and Lewis acid have received most attention. Keywords: Glucose pentaacetate, acidic catalysts, synthesis, investigation. Title:Synthetic Methods of -D-Glucose Pentaacetate Author(s):Gangliang Huang, Qilin Tang, Delin Li, Ying Huang and Dan Zhang Affiliation:Chemistry, Chongqing Normal University, Chongqing, 401331, China. Keywords:Glucose pentaacetate, acidic catalysts, synthesis, investigation. Abstract:Research on the synthesis of -D-glucose pentaacetate 2 was investigated. In particular, various methodsutilized for the synthesis of compound 2 were described in detail. Among them, acid catalysts including protonicacid and Lewis acid have received most attention. Continue reading >>

Ochem Grinard Reaction

Ochem Grinard Reaction

what is produced when a grinart reagent reacts with dry ice what is the side reaction of grinard reactions Wurtz type coupling where one molecule of phenylmagnesium bromide reacts with a molecule of bromobenzene to form biphenyl and magnesium bromide. this is why bromobenzene is added slowly to magnesium in ether. Wurtz product must be separated during the work up or purification steps if they contain 6 or more carbons they are soluble in organic solvents but are not soluble in water. If pH is raised these compounds will dissolve in water. So separate by adding base, it will go to aq layer, then once that layer is separated neutralize base and get rid of aqueous part what are we preparing a grinard from? Then what? bromobenzene and magnesium. Then put in dry ice to synthesize benzoic acid (benzene with a carboxylic acid on it. will isolate benzoic acid and remove biphenyl by extracting with an aq base (biphenyl will stay in organic solution) and neutralizing the basic solution how are single carbohydrate molecules made in nature photosynthesis combining water and carbon dioxide what state do carbohydrate molecules stay in and why? because they have a carbonyl and alcohol functional groups they exist in equilibrium between straight chain and cyclic what are the cyclic carbohydrates a result of? what configurations can they be in? internal hemiacetal formation. or configurations what happens to make glucose cyclic? draw it too alcohol on C5 attacks carbonyl carbon to form 6 membered ring that is more stable what happens when the hemiacetal is formed? new chiral center is formed that is in either or configuration what is the hemiacetal carbon? what is it also referred to as? the carbon that was attacked by OH on C5. only carbon attached to two O atoms. anomeric carbon wha Continue reading >>

Insulinotropic Action Of Alpha-d-glucose Pentaacetate: Functional Aspects.

Insulinotropic Action Of Alpha-d-glucose Pentaacetate: Functional Aspects.

1. Am J Physiol. 1997 Dec;273(6 Pt 1):E1090-101. Insulinotropic action of alpha-D-glucose pentaacetate: functional aspects. Malaisse WJ(1), Snchez-Soto C, Larrieta ME, Hiriart M, Jijakli H, Viambres C,Villanueva-Peacarrillo ML, Valverde I, Kirk O, Kadiata MM, Sener A. (1)Laboratory of Experimental Medicine, Brussels Free University, Belgium. The functional determinants of the insulinotropic action of alpha-D-glucosepentaacetate were investigated in rat pancreatic islets. The ester mimicked theeffect of nutrient secretagogues by recruiting individual B cells into an active secretory state, stimulating proinsulin biosynthesis, inhibiting 86Rb outflow,and augmenting 45Ca efflux from prelabeled islets. The secretory response to the ester was suppressed in the absence of Ca2+ and potentiated by theophylline orcytochalasin B. The generation of acetate from the ester apparently played asmall role in its insulinotropic action. Thus acetate, methyl acetate, ethylacetate, alpha-D-galactose pentaacetate, and beta-D-galactose pentaacetate allfailed to stimulate insulin release. The secretory response to alpha-D-glucosepentaacetate was reproduced by beta-D-glucose pentaacetate and, to a lesserextent, by beta-L-glucose pentaacetate. It differed from that evoked byunesterified D-glucose by its resistance to 3-O-methyl-D-glucose,D-mannoheptulose, and 2-deoxy-D-glucose. It is concluded that the insulinotropic action of alpha-D-glucose pentaacetate, although linked to the generation of the hexose from its ester, entails a coupling mechanism that is not identical to thatcurrently implied in the process of glucose-induced insulin release. Continue reading >>

The Mechanisms Of Glucose Pentaacetate Anomerization And Levoglucosan Formationl

The Mechanisms Of Glucose Pentaacetate Anomerization And Levoglucosan Formationl

THE MECHANISMS OF GLUCOSE PENTAACETATE ANOMERIZATION AND LEVOGLUCOSAN FORMATIONL Download "THE MECHANISMS OF GLUCOSE PENTAACETATE ANOMERIZATION AND LEVOGLUCOSAN FORMATIONL" 1 THE MECHANSMS OF GLUCOSE PENTAACETATE ANOMERZATON AND LEVOGLUCOSAN FORMATONL The stannic chloride catalyzed anomerization of the pentaacetyl-d-gl~~copyranoses in chloroform solution is specific for the C1-acetoxy group. Thc reactions involve complete dissociation of the Cl-carbon atoll1 to acetosy group bond with an intermediate formation of carbonium ions. The initial step of the befu to alpha rearrangement is a rapid dissociation, involving the participation of the C2-acetouy group, to a resonance-stabilized carbonium ion with the lactol carbon atom occupied in the a-configuration. The rate-controlling step in the reaction appears to be the rearrangement of this ion to other ions which are capable of recombining with acetate ion to yield the a-acetate. The a-acetate is highly stable, as compared to thep-anomer, and thedissociationof thec1-carbon atom to acetoxy grorlp bond is the rate-controlling step in its rearrangement. The stability of the a-acetate toward a variety of acidic reagents which readily dissociate is pointed out. For example, although the a-acetate is highly stable toward titanium tetrachloride, the reaction of the p-anomer with this reagent, to yield tetraacetyl-p-d-glucopyranosyl chloride, is extremely fast. This product is unstable under the reaction conditions used and rearranges to the a-form at a measurable rate. 1, 2, 3, 4-Tetraacetyl-P-D-glucopyranose with stannic chloride in chloroform solutio~l yielded triacetyl-d-glucosan < 1, 5>P <, 6>. The alkaline hydrolysis of triacetyl-d-glucosa11 <1, 5> a <1, 2> yielded D-glucosan < 1, 5> 0 < 1, 6>. The mechanisms of these reacti Continue reading >>

An Error Occurred Setting Your User Cookie

An Error Occurred Setting Your User Cookie

An Error Occurred Setting Your User Cookie This site uses cookies to improve performance. If your browser does not accept cookies, you cannot view this site. There are many reasons why a cookie could not be set correctly. Below are the most common reasons: You have cookies disabled in your browser. You need to reset your browser to accept cookies or to ask you if you want to accept cookies. Your browser asks you whether you want to accept cookies and you declined. To accept cookies from this site, use the Back button and accept the cookie. Your browser does not support cookies. Try a different browser if you suspect this. The date on your computer is in the past. If your computer's clock shows a date before 1 Jan 1970, the browser will automatically forget the cookie. To fix this, set the correct time and date on your computer. You have installed an application that monitors or blocks cookies from being set. You must disable the application while logging in or check with your system administrator. This site uses cookies to improve performance by remembering that you are logged in when you go from page to page. To provide access without cookies would require the site to create a new session for every page you visit, which slows the system down to an unacceptable level. This site stores nothing other than an automatically generated session ID in the cookie; no other information is captured. In general, only the information that you provide, or the choices you make while visiting a web site, can be stored in a cookie. For example, the site cannot determine your email name unless you choose to type it. Allowing a website to create a cookie does not give that or any other site access to the rest of your computer, and only the site that created the cookie can read it. Continue reading >>

Iron(iii) Chloride Catalyzed Glycosylation Of Peracylated Sugars With Allyl/alkynyl Alcohols

Iron(iii) Chloride Catalyzed Glycosylation Of Peracylated Sugars With Allyl/alkynyl Alcohols

Iron(III) chloride catalyzed glycosylation of peracylated sugars with allyl/alkynyl alcohols Senthil Narayanaperumal; Rodrigo Csar da Silva; Julia L. Monteiro; Arlene G. Corra; Mrcio W. Paixo * Departamento de Qumica, Universidade Federal de So Carlos, 13565-905 So Carlos-SP, Brazil In this work, the use of ferric chloride as an efficient catalyst in glycosylation reactions of sugars in the presence of allyl and alkynyl alcohols is described. The corresponding glycosides were obtained with moderate to good yields. This new procedure presented greater selectivity when compared to classic methods found in the literature. Principal features of this simple method include non-hazardous reaction conditions, low-catalyst loading, good yields and high anomeric selectivity. Keywords: glycosylation, iron(III) chloride, stereoselective, carbohydrate, green chemistry Neste trabalho, o emprego de cloreto frrico como um eficiente catalisador em reaes de glicosilao de acares na presena de lcoois allicos e proparglicos descrito. Os glicosdios correspondentes foram obtidos com rendimentos de moderados a bons. Este novo procedimento apresenta maior seletividade quando comparado a mtodos clssicos encontrados na literatura. As principais caractersticas desse mtodo simples incluem condies de reao no perigosas, quantidade de catalisador baixa, bom rendimento e seletividade anomrico elevada. Many carbohydrate-containing complex natural compounds are found in nature as important biological substances. Recent biological studies on these glycosides, such as proteoglycans, glycoproteins, glycolipid and antibiotics at the molecular level have shed light on the biological significance of their carbohydrate parts (glycons) in molecular recognition for the transmission of biological information.1 Wi Continue reading >>

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