CS254694B1 - Method of stereospecific preparation of 1,6-anhydro-3,4-di-O-acetyl-β-D-glucopyranose - Google Patents

Abstract

The solution relates to the field of chemistry and biochemistry of carbohydrates. The solution is a method for stereospecific preparation of 1,6-anhydro-3,4-di-O-acetyl-β-D-glucopyranose by treating cells of Aureobasidium pullulans CCY 27-1-14&. The stated purpose is achieved by treating a solution of 1,6-anhydro-2,3,4- -tri-O-acetyl-β-D-glucopyranose in a citrate phosphate buffer of 0.01 to 0.05 mol. . drn”3 and pH 5.0 to 5.8 with a suspension of cells or immobilized cells of Aureobasidium pullulans. The use is in the basic chemistry and biochemistry of carbohydrates, especially in the preparation of D-glucose derivatives modified in the C-2 position, or for the preparation of disaccharides.

Description

The solution relates to the field of carbohydrate chemistry and biochemistry.

A method for the stereospecific preparation of 1,6-anhydro-3,4-di-O-acetyl- [beta] -D-glucopyranose by treatment with Aureobasidium pullulans CCY 27-l-14a cells. This purpose is achieved by providing a solution of 1,6-anhydro-2,3,4-tri-O-acetyl-d-D-glucopyranose in citrate phosphate buffer of 0.01 to 0.05 moles. . dm-3 and pH 5.0-5.8 are provided by cell suspension or immobilized Aureobasldium pullulans.

It is used in basic chemistry and biochemistry of carbohydrates, especially in the preparation of a D-glucose derivative modified at C-2, or for the preparation of disaccharides. 254694 254 3

The invention relates to the stereospecific preparation of 1'-ananhydro-5'-di-O-acetyl-β-D-glucopyranose. 1,6-anhydro-iD-glucopyra nose (levoglucosane) and its acetylated derivatives are useful precursors in the preparation of many glucose derivatives (deoxycucars, amine sugars, thioeukers, disaccharides, and the like) and therefore find wide use as pure chemicals suitable for theoretical study of chemistry and biochemistry of carbohydrates. The method of their preparation so far is the direct acetylation of 1,6-anhydro-D-glucopyranos [D. Shapiro, Y. Rabinsohn, A. J. Acher, A. Diver-Haber, J. Org. Chem. 35, 1464 (1970), or a chemical hydrolysis of a 2,3,4-tri-O-acetyl derivative [S. Kučár, J. Zámocký, J. Zemek, D. Anderle, M. Matulová: Gollection Czechoslov. Chem. Commun. 49, 1780 (1984)]. The disadvantage of the above processes is the low stereospecificity of the reaction, which in most cases produces a mixture of mono- and di-acetyl derivatives. The stereospecific method for preparing 2,3-di-O-acetyl and 2,4-di-O-acetyl derivatives can be ensured by the use of selected esterases, lipases or proteases in soluble or immobilized state [Cs. AO No. 240 331; Čsl. AO No. 240,333; J. Zemek, 5. Kucar, D. Anderle: Collection Czechoslov. Chem. Commun. (1985)]. A similar stereospecific method for the preparation of 3,4-di-O-acetyl derivative of levoglucose has not been described so far.

The aforementioned drawbacks are substantially eliminated by the process of the invention, which consists in providing a suspension of Aureobasidium pullulans CCY 27-l-14a cells in 0.01 to 0.05 moles. dm-3 citrate-phosphate buffer 0 'pH 5 to 5.8 at 20-40 ° C to 1,6-anhydro-2,3,4-tri-O-acetyl-4-D-glucopyranose. The yield of 1,6-anhydro-3,4-di-O-acetyl β-D-glucopyranose in this reaction is about 90%. Of the by-products of this deacetylation reaction, 1.e.-anhydro-S-O-acetyl-.beta.-D-glucopyranose predominates, the proportion of which in the reaction mixture does not exceed 7%. The advantage of this process is its simplicity and high yield of 1,6-anhydro-3,4-di-O-acetyl- [beta] -D-glucopyranose in one reaction step. EXAMPLE 1 1, 6-Anhydro-2,3,4-tri-O-acetyl-β-D-glucopyranose (Dissolve 1 g in 10 cm @ 3 of methanol and add this solution to 50 cm @ 3 of citrate phosphate buffer 0 PH 5.8, dm-3, and 100 mg of Aureobasidium pullulans CCY 27-l-14a lyophilized cells were cultured to a late exponential growth phase on a YNB growth pod (6 g.dm-3). ), Ye-ast Nitrogen Base with D-glucose (15 gm-3) and 1,6-anhydro-2,3,4-tri-O-acetyl- [3-D-glucopyranose (0.5 grams). The hydrolysis was carried out at a temperature of 20 ° C for 48 hours, and the reaction product obtained contained 92.5% normalized, i.e. 925 mg of 1,6-anhydro-3,4-di-O-acetyl-SD-glucopyranose. Separation of 1,6-anhydro-3,4-di-O-acetyl-β-D-gluc-opyranose from the by-products of the deacetylation reaction, between which 3-O-acetyl derivative (45 mg) predominated, was chromatographed on a column with a silica gel cartridge in a chromatographic system of ethyl acetate: benzene: 2-one panol (8: 4: 1 by volume) Example 2

The procedure is as in Example 1, except that 0.01 mole is used. . dm "3 citrate-phosphate buffer pH 5.0 and sieved fraction of cells Aureobasidium pullulans CCY 27-1-14a (100 mils, 0.06-0.120 mm) immobilized according to CsI AO # 232 642. The hydrolysis was carried out at 40 ° C for 36 hours, and the reaction product obtained was found to be 93% normalized, i.e. 930 mg of 1,6-anhydro-3,4-di-O-acetyl-4-D-glucopyranose.

The invention can be widely used in basic organic synthesis of carbohydrates, especially glucose derivatives modified substitutionally at the C-2 hydroxyl group and oligosaccharides composed of D-glucopyranosyl units bound by α or β-1,2-bonds.

Claims (1)

SUBJECT A process for the stereospecific preparation of 1,6-anhydro-3,4-di-O-acetyl-β-D-glucopyranose, characterized in that the suspension of Aureobasidium pullulans CCY 27-1-14a cells is from 0.01 to 1%. We claim: 0.05 mol. dm- ³ citrate phosphate buffer pH 5.0-5.8 at temperature 20-40 ° C catalytically affects 1,6-anhydro-2,3,4-tri-Q-acetyl- [beta] -D-glucopyranose.