CA2157548A1 - Process for preparing alkyl glycosides having a low degree of glycosidation - Google Patents
Process for preparing alkyl glycosides having a low degree of glycosidationInfo
- Publication number
- CA2157548A1 CA2157548A1 CA002157548A CA2157548A CA2157548A1 CA 2157548 A1 CA2157548 A1 CA 2157548A1 CA 002157548 A CA002157548 A CA 002157548A CA 2157548 A CA2157548 A CA 2157548A CA 2157548 A1 CA2157548 A1 CA 2157548A1
- Authority
- CA
- Canada
- Prior art keywords
- glycosidation
- alkyl
- alcohol
- process according
- molar ratio
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07H—SUGARS; DERIVATIVES THEREOF; NUCLEOSIDES; NUCLEOTIDES; NUCLEIC ACIDS
- C07H15/00—Compounds containing hydrocarbon or substituted hydrocarbon radicals directly attached to hetero atoms of saccharide radicals
- C07H15/02—Acyclic radicals, not substituted by cyclic structures
- C07H15/04—Acyclic radicals, not substituted by cyclic structures attached to an oxygen atom of the saccharide radical
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07H—SUGARS; DERIVATIVES THEREOF; NUCLEOSIDES; NUCLEOTIDES; NUCLEIC ACIDS
- C07H1/00—Processes for the preparation of sugar derivatives
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Biotechnology (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Biochemistry (AREA)
- Health & Medical Sciences (AREA)
- General Health & Medical Sciences (AREA)
- Genetics & Genomics (AREA)
- Molecular Biology (AREA)
- Crystallography & Structural Chemistry (AREA)
- Saccharide Compounds (AREA)
- Detergent Compositions (AREA)
- Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
Abstract
According to the present process, alkyl glycosides having C8 to C20 alkyl radicals, having a mean degree of glycosi-dation of 1.05 to 1.4 and a low polysaccharide content are prepared by using a monosaccharide having a dextrose equivalent of 96 to 99.5 and setting, in the glycosida-tion, a monosaccharide/alcohol molar ratio of 1:5 to 1:20 and, in the transglycosidation, an alkyl glycoside/fatty alcohol molar ratio of 1:2 to 1:10.
Description
21a~548 - 1 - O.Z. 4864 Process for Preparinq alkyl qlycosides havinq a low deqree of qlycosidation S The invention relates to a novel process for preparing alkyl glycosides by glycosidation and transglycosidation, the alkyl glycosides having C8 to C20 alkyl radicals and a mean degree of glycosidation of l.OS to 1.4 and a polysaccharide content of up to 10%.
Alkyl glycosides having C8 to C20 alkyl groups can be prepared in whole or in part from renewable raw materials. Therefore, and also because of their very good biodegradability, they are becoming increasingly import-ant. In addition to their surfactant properties of lS interest, the products have the advantage that their polarity can be set exactly via the length of the alkyl chain and the degree of glycosidation. By this means the alkyl glycosides can be directed specifically to their field of application.
In the two-stage alkyl glycoside preparation, a glycosidation is first carried out. From saccharides and C2 to C6 alcohols, alkyl glycosides having short-chain alkyl groups are prepared in this stage. These products are then converted in the second stage into the desired alkyl glycosides having surfactant properties by transglycosidation using C8 to C20 alcohols.
This preparation route has long been known. Recent appli-cations in this sector frequently concern the preparation of products improved in colour. In these cases, reducing agents are sometimes added or special apparatus is sometimes used.
Thus in EP-A-0 501 032, the glycosidation is performed in - 2 - O.Z. 4864 an evaporator. The glucose syrup preferably used there is generally a starch hydrolysate containing oligosaccharide. The dextrose equivalent of such syrups is usually 90 to 95. The alkyl polyglycosides having long-chain alkyl groups prepared here preferably have mean degrees of glycosidation in the range from 1.3 to S, a value of 1.65 being specified in the example.
According to EP-A-0 514 628, the transglycosidation can also be performed in an evaporator. In EP-A-0 514 627, the transglycosidation is carried out in a reaction column. In this case a molar ratio of alkyl glycoside having short alkyl radical to long-chain alcohol of 1:2 to 1:15 is set and alkyl polyglycosides having degrees of glycosidation of preferably 1.2 to 3 are obtained.
To separate by distillation the fatty alcohols from alkyl polyglycosides having C~0 to Cl8 alkyl groups and a mean degree of glycosidation of 1.05 to 1.4, according to DE-A-41 29 587, a thin-layer evaporator is used. The preparation of the alkyl polyglycosides is not considered in more detail here.
WO 93/101 33 describes a two-stage process for preparing alkyl oligoglycosides which can be carried out continu-ously or discontinuously and in which a glucose syrup having a monomeric glucose content of 90 to 100% is used.
The process described here is highly complex overall. It requires a secondary reaction both in the glycosidation and in the transglycosidation. In addition, in both reaction stages, narrow temperature ranges must be main-tained. WO 93/101 33 delivers alkyl oligoglucosides here having a polyglucose content of at least 4.7 per cent by weight. No details are given on the mean degree of glucosidation.
The pu~lications mentioned do not give an indication as to how alkyl glycosides having mean degrees of 2 1~ 8 glycosidation of 1.05 to 1.4 and simultaneously low contents of polysaccharide may be prepared in a simple manner.
It is attempted therefore according to the present invention, to provide a simple two-stage process for preparing alkyl glycosides having C8 to C20 alkyl radicals and having a mean degree of glycosidation of 1.05 to 1.4 and a low poly-saccharide content. Moreover, the products are also to have a good colour quality.
According to the invention, a monosaccharide having a dextrose equivalent of 96 to 99.5 is used and in addition, in the glycosidation, a molar ratio of monosaccharide to C2 to C6 alcohol of 1:5 to 1:20 is set and, in the transglycosidation, a molar ratio of alkyl glycoside having C2 to C6 alkyl radical to C8 to C20 fatty alcohol of 1:2 to 1:10 is set.
Surprisingly, without filtration steps, for example in simple stirred-tank cascades, products attractive in colour and having a low degree of glycosidation and low polysaccharide content are successfully prepared by means of these measures.
Monosaccharides which can be used for the process are for example glucose, mannose, galactose, gulose, allose or talose. Preferably, glucose is used here. The mono-saccharides can also be used here in the form of an aqueous syrup which can contain up to 50% water.
To characterize the monosaccharides, the content of reducing sugars is determined, calculated as dextrose on the - 2~57~8 - 3a -basis of dry matter, and termed dextrose equivalent. ~Ihereas therefore a pure hexopyranose, such as glucose, has a dextrose equivalent of 100, dextrose equivalents below 100 indicate a content of oligosaccharides. According to the invention, the dextrose equivalent is 215~ 48 ~ - - 4 - O.Z. 4864 preferably 96 to 99.
Alcohols usable for the glycosidation which are suitable are, for example, ethanol, n-propanol, isopropanol, n-butanol, t-butanol, amyl alcohol or hexanol.
S Monosaccharide and Cz to C6 alcohol are preferably reacted in a molar ratio of l:S to 1:10.
The alkyl glycosides having C2 to C6 alkyl chains prepared in the glycosidation are reacted with C8 to C20 fatty alcohols in a second stage, the transglycosidation. The fatty alcohols in this stage can be linear or branched.
They can also contain olefinic double bonds. Natural or synthetic fatty alcohols or fatty alcohol mixtures can be used. Examples which may be mentioned are octanol, decanol, 10-undecen-1-ol, dodecanol, myristyl alcohol and lS stearyl alcohol. Preferably, fatty alcohols having 10 to 14 C atoms are used. The alkyl glycoside having C2 to C6 alkyl groups is usually reacted with the fatty alcohol in a molar ratio of 1:4 to 1:10.
In the glycosidation and transglycosidation the acid catalysts used can be mineral acids, such as sulphuric acid or hydrochloric acid. Organic acids are also very suitable, such as arylsulphonic, alkylsulphonic or aralkylsulphonic acids. The reaction temperature in this case is generally in the range from 100 to 140C. The glycosidation is preferably carried out at 100 to 125C.
In the transglycosidation, the reaction temperature is usually 105 to 135C, vacuum usually being applied to accelerate the reaction, i.e. to separate off the short-chain alcohol.
The two-stage preparation of the alkyl glycosides can be performed continuously or discontinuously. The continuous alkyl glycoside synthesis is usually carried out in a stirred-tank cascade, where the stirred tanks can also be - - 5 - O.Z. 4864 replaced in part or in whole by reaction columns or tubular reactors.
The product of the transglycosidation is neutralized with suitable bases in a known manner. The excess fatty alcohol is then separated off by distillation which can be performed in a thin-layer evaporator or short-path evaporator. The alkyl glycoside obtained which preferably has a mean degree of glycosidation of 1.1 to 1.3 is then mixed with water and bleached using peroxide. The end product has an iodine colour value (ICV) of less than 20 and preferably a residual fatty alcohol content of less than 1%.
The products are distinguished, furthermore, by a low polysaccharide content of up to 10%. This content is based on the solids, that is the sum of alkyl glycoside and polysaccharide. The polysaccharide content is prefer-ably 1 to 10%.
The process according to the invention, when monosaccha-rides of the said quality are used and when the claimed molar ratios are maintained, leads to reaction mixtures which, because of the low polysaccharide content, have a very low content of undissolved constituents. Piping and reactors therefore do not have a tendency to blockages.
This increases the operational safety. At the same time, alkyl glycosides having a low degree of glycosidation are obtained directly, as are used advantageously in washing agents and dishwashing agents.
The following examples are intended to describe the invention.
ComParison Example A
A cascade of two 4 1 stirred reactors is fed with 1.5 1 of n-butanol, 100 ml of butanolic p-toluenesulphonic acid ~157548 - 6 - O.Z. 4864 solution (173 g/l of p-toluenesulphonic acid) and 540 ml of 70% strength glucose solution per hour. The glucose used has a dextrose equivalent of 95. Water is distilled off azeotropically via attached columns at 120C internal temperature. The n-butanol likewise distilled during this is recycled to the column after separating off the water phase. Approximately 1850 ml of solution of approximately 65% butanol and 35% butyl glucoside leave the second stirred reactor per hour.
This product is mixed with a stream of 4 l of fatty alcohol (mixture of 68% dodecanol, 26% tetradecanol and 6% hexadecanol) and then passed through a further cascade of two 4 l stirred reactors. At a reaction temperature of 120C and 45 mbar (first reactor) and 5 mbar (second reactor) butanol is distilled off via an attached column.
The product, an approximately 25% strength fatty alco-holic alkyl glucoside solution, is adjusted to pH 10 using 25% strength NaOH (measured in a 1:1:1 mixture of product solution, isopropanol and water). The fatty alcohol is then distilled off in vacuo in a cascade of thin-layer evaporators down to a residual content of approximately 1%. The alkyl glucoside obtained has a mean degree of glycosidation of 1.44 and a polyglucose content of 13.5%.
Example 1 The procedure as in Comparison Example A is followed, but glucose having a dextrose equivalent of 99 is used. In this case, an alkyl glycoside is obtained having a mean degree of glycosidation of 1.16 and a polyglucose content of 6.9%.
Alkyl glycosides having C8 to C20 alkyl groups can be prepared in whole or in part from renewable raw materials. Therefore, and also because of their very good biodegradability, they are becoming increasingly import-ant. In addition to their surfactant properties of lS interest, the products have the advantage that their polarity can be set exactly via the length of the alkyl chain and the degree of glycosidation. By this means the alkyl glycosides can be directed specifically to their field of application.
In the two-stage alkyl glycoside preparation, a glycosidation is first carried out. From saccharides and C2 to C6 alcohols, alkyl glycosides having short-chain alkyl groups are prepared in this stage. These products are then converted in the second stage into the desired alkyl glycosides having surfactant properties by transglycosidation using C8 to C20 alcohols.
This preparation route has long been known. Recent appli-cations in this sector frequently concern the preparation of products improved in colour. In these cases, reducing agents are sometimes added or special apparatus is sometimes used.
Thus in EP-A-0 501 032, the glycosidation is performed in - 2 - O.Z. 4864 an evaporator. The glucose syrup preferably used there is generally a starch hydrolysate containing oligosaccharide. The dextrose equivalent of such syrups is usually 90 to 95. The alkyl polyglycosides having long-chain alkyl groups prepared here preferably have mean degrees of glycosidation in the range from 1.3 to S, a value of 1.65 being specified in the example.
According to EP-A-0 514 628, the transglycosidation can also be performed in an evaporator. In EP-A-0 514 627, the transglycosidation is carried out in a reaction column. In this case a molar ratio of alkyl glycoside having short alkyl radical to long-chain alcohol of 1:2 to 1:15 is set and alkyl polyglycosides having degrees of glycosidation of preferably 1.2 to 3 are obtained.
To separate by distillation the fatty alcohols from alkyl polyglycosides having C~0 to Cl8 alkyl groups and a mean degree of glycosidation of 1.05 to 1.4, according to DE-A-41 29 587, a thin-layer evaporator is used. The preparation of the alkyl polyglycosides is not considered in more detail here.
WO 93/101 33 describes a two-stage process for preparing alkyl oligoglycosides which can be carried out continu-ously or discontinuously and in which a glucose syrup having a monomeric glucose content of 90 to 100% is used.
The process described here is highly complex overall. It requires a secondary reaction both in the glycosidation and in the transglycosidation. In addition, in both reaction stages, narrow temperature ranges must be main-tained. WO 93/101 33 delivers alkyl oligoglucosides here having a polyglucose content of at least 4.7 per cent by weight. No details are given on the mean degree of glucosidation.
The pu~lications mentioned do not give an indication as to how alkyl glycosides having mean degrees of 2 1~ 8 glycosidation of 1.05 to 1.4 and simultaneously low contents of polysaccharide may be prepared in a simple manner.
It is attempted therefore according to the present invention, to provide a simple two-stage process for preparing alkyl glycosides having C8 to C20 alkyl radicals and having a mean degree of glycosidation of 1.05 to 1.4 and a low poly-saccharide content. Moreover, the products are also to have a good colour quality.
According to the invention, a monosaccharide having a dextrose equivalent of 96 to 99.5 is used and in addition, in the glycosidation, a molar ratio of monosaccharide to C2 to C6 alcohol of 1:5 to 1:20 is set and, in the transglycosidation, a molar ratio of alkyl glycoside having C2 to C6 alkyl radical to C8 to C20 fatty alcohol of 1:2 to 1:10 is set.
Surprisingly, without filtration steps, for example in simple stirred-tank cascades, products attractive in colour and having a low degree of glycosidation and low polysaccharide content are successfully prepared by means of these measures.
Monosaccharides which can be used for the process are for example glucose, mannose, galactose, gulose, allose or talose. Preferably, glucose is used here. The mono-saccharides can also be used here in the form of an aqueous syrup which can contain up to 50% water.
To characterize the monosaccharides, the content of reducing sugars is determined, calculated as dextrose on the - 2~57~8 - 3a -basis of dry matter, and termed dextrose equivalent. ~Ihereas therefore a pure hexopyranose, such as glucose, has a dextrose equivalent of 100, dextrose equivalents below 100 indicate a content of oligosaccharides. According to the invention, the dextrose equivalent is 215~ 48 ~ - - 4 - O.Z. 4864 preferably 96 to 99.
Alcohols usable for the glycosidation which are suitable are, for example, ethanol, n-propanol, isopropanol, n-butanol, t-butanol, amyl alcohol or hexanol.
S Monosaccharide and Cz to C6 alcohol are preferably reacted in a molar ratio of l:S to 1:10.
The alkyl glycosides having C2 to C6 alkyl chains prepared in the glycosidation are reacted with C8 to C20 fatty alcohols in a second stage, the transglycosidation. The fatty alcohols in this stage can be linear or branched.
They can also contain olefinic double bonds. Natural or synthetic fatty alcohols or fatty alcohol mixtures can be used. Examples which may be mentioned are octanol, decanol, 10-undecen-1-ol, dodecanol, myristyl alcohol and lS stearyl alcohol. Preferably, fatty alcohols having 10 to 14 C atoms are used. The alkyl glycoside having C2 to C6 alkyl groups is usually reacted with the fatty alcohol in a molar ratio of 1:4 to 1:10.
In the glycosidation and transglycosidation the acid catalysts used can be mineral acids, such as sulphuric acid or hydrochloric acid. Organic acids are also very suitable, such as arylsulphonic, alkylsulphonic or aralkylsulphonic acids. The reaction temperature in this case is generally in the range from 100 to 140C. The glycosidation is preferably carried out at 100 to 125C.
In the transglycosidation, the reaction temperature is usually 105 to 135C, vacuum usually being applied to accelerate the reaction, i.e. to separate off the short-chain alcohol.
The two-stage preparation of the alkyl glycosides can be performed continuously or discontinuously. The continuous alkyl glycoside synthesis is usually carried out in a stirred-tank cascade, where the stirred tanks can also be - - 5 - O.Z. 4864 replaced in part or in whole by reaction columns or tubular reactors.
The product of the transglycosidation is neutralized with suitable bases in a known manner. The excess fatty alcohol is then separated off by distillation which can be performed in a thin-layer evaporator or short-path evaporator. The alkyl glycoside obtained which preferably has a mean degree of glycosidation of 1.1 to 1.3 is then mixed with water and bleached using peroxide. The end product has an iodine colour value (ICV) of less than 20 and preferably a residual fatty alcohol content of less than 1%.
The products are distinguished, furthermore, by a low polysaccharide content of up to 10%. This content is based on the solids, that is the sum of alkyl glycoside and polysaccharide. The polysaccharide content is prefer-ably 1 to 10%.
The process according to the invention, when monosaccha-rides of the said quality are used and when the claimed molar ratios are maintained, leads to reaction mixtures which, because of the low polysaccharide content, have a very low content of undissolved constituents. Piping and reactors therefore do not have a tendency to blockages.
This increases the operational safety. At the same time, alkyl glycosides having a low degree of glycosidation are obtained directly, as are used advantageously in washing agents and dishwashing agents.
The following examples are intended to describe the invention.
ComParison Example A
A cascade of two 4 1 stirred reactors is fed with 1.5 1 of n-butanol, 100 ml of butanolic p-toluenesulphonic acid ~157548 - 6 - O.Z. 4864 solution (173 g/l of p-toluenesulphonic acid) and 540 ml of 70% strength glucose solution per hour. The glucose used has a dextrose equivalent of 95. Water is distilled off azeotropically via attached columns at 120C internal temperature. The n-butanol likewise distilled during this is recycled to the column after separating off the water phase. Approximately 1850 ml of solution of approximately 65% butanol and 35% butyl glucoside leave the second stirred reactor per hour.
This product is mixed with a stream of 4 l of fatty alcohol (mixture of 68% dodecanol, 26% tetradecanol and 6% hexadecanol) and then passed through a further cascade of two 4 l stirred reactors. At a reaction temperature of 120C and 45 mbar (first reactor) and 5 mbar (second reactor) butanol is distilled off via an attached column.
The product, an approximately 25% strength fatty alco-holic alkyl glucoside solution, is adjusted to pH 10 using 25% strength NaOH (measured in a 1:1:1 mixture of product solution, isopropanol and water). The fatty alcohol is then distilled off in vacuo in a cascade of thin-layer evaporators down to a residual content of approximately 1%. The alkyl glucoside obtained has a mean degree of glycosidation of 1.44 and a polyglucose content of 13.5%.
Example 1 The procedure as in Comparison Example A is followed, but glucose having a dextrose equivalent of 99 is used. In this case, an alkyl glycoside is obtained having a mean degree of glycosidation of 1.16 and a polyglucose content of 6.9%.
Claims (8)
1. A process for preparing an alkyl glycoside having a C8 to C20 alkyl radical, a mean degree of glycosidation of 1.05 to 1.4 and a polysaccharide content of no more than 10%, which comprises:
a glycosidation of a monosaccharide having a dextrose equivalent of 96 to 99.5 with a C2 to C6 alcohol at a mono-saccharide/C2 to C6 alcohol molar ratio of 1:5 to 1:20, thereby obtaining an alkyl glycoside having a C2 to C6 alkyl radical, and a transglycosidation of the thus-obtained alkyl glycoside having a C2 to C6 alkyl radical with a C8 to C20 fatty alcohol at an alkyl glycoside/C8 to C20 fatty alcohol molar ratio of 1:2 to 1:10.
a glycosidation of a monosaccharide having a dextrose equivalent of 96 to 99.5 with a C2 to C6 alcohol at a mono-saccharide/C2 to C6 alcohol molar ratio of 1:5 to 1:20, thereby obtaining an alkyl glycoside having a C2 to C6 alkyl radical, and a transglycosidation of the thus-obtained alkyl glycoside having a C2 to C6 alkyl radical with a C8 to C20 fatty alcohol at an alkyl glycoside/C8 to C20 fatty alcohol molar ratio of 1:2 to 1:10.
2. A process according to claim 1, wherein reaction conditions are so chosen that the mean degree of glycosidation of the alkyl glycoside having a C8 to C20 alkyl radical is 1.1 to 1.3.
3. A process according to claim 1, wherein reaction conditions are so chosen that the polysaccharide content of the resulting alkyl glycoside having a C8 to C20 alkyl radical is 1 to 10%.
4. A process according to claim 1, wherein glucose having a dextrose equivalent of 96 to 99 is used as the mono-saccharide.
5. A process according to claim 1, wherein the mono-saccharide/C2 to C6 alcohol molar ratio of the glycosidation is 1:5 to 1:10 and the alkyl glycoside/C8 to C20 fatty alcohol molar ratio of the transglycosidation is 1:4 to 1:10.
6. A process according to claim 1, wherein a C10 to C14 fatty alcohol is used as the C8 to C20 fatty alcohol.
7. A process according to any one of claims 1 through 6, wherein the glycosidation and the transglycosidation are both conducted in the presence of an acid catalyst; the glycosidation is conducted at a temperature of 100 to 125°C; and the trans-glycosidation is conducted at a temperature of 105 to 135°C
while separating off the C2 to C6 alcohol under vacuum.
while separating off the C2 to C6 alcohol under vacuum.
8. A process according to claim 7, wherein n-butanol is used as the C2 to C6 alcohol.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE4431855A DE4431855A1 (en) | 1994-09-07 | 1994-09-07 | Process for the preparation of alkyl glycosides with a low degree of glycosidation |
| DEP4431855.3 | 1994-09-07 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2157548A1 true CA2157548A1 (en) | 1996-03-08 |
Family
ID=6527632
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002157548A Abandoned CA2157548A1 (en) | 1994-09-07 | 1995-09-05 | Process for preparing alkyl glycosides having a low degree of glycosidation |
Country Status (6)
| Country | Link |
|---|---|
| EP (1) | EP0702023A1 (en) |
| JP (1) | JPH08188583A (en) |
| KR (1) | KR960010675A (en) |
| CN (1) | CN1128266A (en) |
| CA (1) | CA2157548A1 (en) |
| DE (1) | DE4431855A1 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102643313B (en) * | 2012-04-23 | 2015-03-18 | 上海发凯化工有限公司 | Heterogeneous secondary alcohol alkyl glycoside, and synthesis method and application thereof |
| CN104140453B (en) * | 2013-10-29 | 2017-08-04 | 中国石油化工股份有限公司 | A kind of preparation method of drilling fluid glyceryl glucoside |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3833780A1 (en) * | 1988-10-05 | 1990-04-12 | Henkel Kgaa | METHOD FOR THE DIRECT PRODUCTION OF ALKYL GLYCOSIDES |
| DE4104640A1 (en) | 1991-02-15 | 1992-08-20 | Huels Chemische Werke Ag | METHOD FOR PRODUCING LIGHT-COLORED ALKYLPOLYGLYCOSIDES |
| DE4116669A1 (en) | 1991-05-22 | 1992-11-26 | Huels Chemische Werke Ag | METHOD FOR PRODUCING LIGHT-COLORED ALKYLPOLYGLYCOSIDES |
| DE4116665A1 (en) | 1991-05-22 | 1992-11-26 | Huels Chemische Werke Ag | PROCESS FOR THE PREPARATION OF ALKYLPOLYGLYCOSIDES |
| DE4129587A1 (en) | 1991-09-06 | 1993-03-11 | Huels Chemische Werke Ag | METHOD FOR THE DISTILLATIVE SEPARATION OF FATTY ALCOHOLS FROM FATTY ALCOHOLIC ALKYLPOLYGLYCOSIDE SOLUTIONS |
| DE4138250A1 (en) | 1991-11-21 | 1993-05-27 | Henkel Kgaa | METHOD FOR PRODUCING ALKYLOLIGOGLUCOSIDES WITH REDUCED POLYGLUCOSE CONTENT |
-
1994
- 1994-09-07 DE DE4431855A patent/DE4431855A1/en not_active Withdrawn
-
1995
- 1995-07-12 EP EP95110919A patent/EP0702023A1/en not_active Withdrawn
- 1995-09-05 CA CA002157548A patent/CA2157548A1/en not_active Abandoned
- 1995-09-06 KR KR1019950029074A patent/KR960010675A/en not_active Application Discontinuation
- 1995-09-06 JP JP7229349A patent/JPH08188583A/en not_active Withdrawn
- 1995-09-06 CN CN95116217A patent/CN1128266A/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| KR960010675A (en) | 1996-04-20 |
| JPH08188583A (en) | 1996-07-23 |
| EP0702023A1 (en) | 1996-03-20 |
| DE4431855A1 (en) | 1996-03-14 |
| CN1128266A (en) | 1996-08-07 |
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Legal Events
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|---|---|---|---|
| FZDE | Dead |