A New Method for Preparing Hydroxyethyl Ethers of Glucose

Abstract

Three monosubstituted hydroxyethyl ethers of D-glucoSe have been synthesized by a novel method involving reduction of the corresponding carboxymethyl derivatives with lithium aluminum hydride. This technique also allowed introduction for the first time of hydroxyethyl substituents containing polyethyle~le oxide chain5 of a definite length in the glucose molec~~le, as exemplified by the synthesis of 3-0-hydroxyethoxyethyl-D-glucose.T h e quantitative paper chromatographic technique has recently been applied to distribution studies on hydroxyethylcellulose (I). In order to obtain the hydroxyethyl derivatives of glucose which were needed as reference compounds, a glucose derivative with the appropriate hydroxyl groups unsubstituted was reacted with ethylene oxide in the presence of alltali. This nlethotl of preparation was, however, hampered by the fact that further reaction of the l~~d r o x y e t h y l group t o give polyethylene oxide substituents could not be con trolled. 0T h e synthesis of some carboxgnlethyl derivatives of glucose has recently been described (3). I t has been found that the intermediates which were used for this purpose can be converted b y reduction with lithium aluminum hydride into the corresponding hydroxyethyl derivatives of glucose. By repeated carboxymethylation and reduction of the latter, polyethylene oxide substituents of definite length can also be introduced.Thus, reduction of 3-O-carboxyn~ethyl-l,2;5,6-di-0-isopropylidene-~-glucofuranose methyl ester (3) with lithium aluminum hydride in ethyl ether gave the correspondiilg hydroxyethyl derivative as a sirup. T h e latter was hydro- For personal use only.

Preparation and Evaluation of Hydroxyethyl Starch

“…The results of thin-layer chromatography confirmed that the substitution occurred predominantly at C2. These findings agreed with the work of Shyluk and Time11 [15].…”

“…Owing to the unavailability of authentic samples of hydroxyethyl-D-glucose derivatives, some of the located spots in front of those of glucose on the chromatogram plates were isolated, dissolved in water and examined polarimetrically. An initial value of [a];' + 25 was obtained after 2 min and the final value was [a];' = + 47, after 2 h. This was in good agreement with the results found by Shyluk and Time11 [15] for 2-0hydroxyethyl-glucose.…”

Differences in chemical structures between waxy maize‐ and potato starch‐based hydroxyethyl starch volume therapeutics

“…In brief, after hydrolysis of HES to the oligomeric glucose units by sulfuric acid these were separated by HPLC with refractive index (RI) detection. The peak identification data of the literature were confirmed by independently synthesized samples according to literature of hydroxyethyl glucoses 15,16 . In contrary to the assumption of Ferber, 14 the response factor of 1,2‐O‐ethylenglucose was different from those of the other mono‐ and di‐substituted hydroxyethyl glucose isomers, as was shown by measurement of the independently synthesized sample of 1,2‐O‐ethylenglucose.…”

“…The peak identification data of the literature were confirmed by independently synthesized samples according to literature of hydroxyethyl glucoses. 15,16 In contrary to the assumption of Ferber, 14 the response factor of 1,2-O-ethylenglucose was different from those of the other mono-and di-substituted hydroxyethyl glucose isomers, as was shown by measurement of the independently synthesized sample of 1,2-O-ethylenglucose. For all other isomers the response factors were identical and equal to the one of unsubstituted glucose.…”

0-(2-hydroxyethyl)-amylose as the substrate of porcine pancreatic [alpha]-amylase action: structural analysis of 0-(2-hydroxyethyl)-maltooligosaccharides

“…Three solvent systems were commonly used: Both solvent systems (A) and vS) were utilized in the ascending technique at 65*C (115). Descending paper chromatography was performed by solvent systems (C) at room temperature (93,94). Alkaline AgNO^ was used in the detection of the reducing carbohydrates (116).…”