CN101073378A - Synthesis of animal nutrient additive amino-acid-selenomethionine - Google Patents
Synthesis of animal nutrient additive amino-acid-selenomethionine Download PDFInfo
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- CN101073378A CN101073378A CNA2007100287340A CN200710028734A CN101073378A CN 101073378 A CN101073378 A CN 101073378A CN A2007100287340 A CNA2007100287340 A CN A2007100287340A CN 200710028734 A CN200710028734 A CN 200710028734A CN 101073378 A CN101073378 A CN 101073378A
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- selenomethionine
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Abstract
The invention is concerned with a kind of method to produce amino acid-selenium methionine as animal nutrition additive. Take dimethyl diselenide as material and deoxidize it in alkalescence solution to get methyl hydroselenide negative ion with borohydride metal or metal of borohydride. Then react with 4-halogen-alpha-amino acid or its ramification to get selenium methionine through hydrolyzing and adjusting pH valve. The reaction system is carrying in water solution without inert gases and avoids the operation without water and oxygen. The material is common with good safety and it is easy for operation and higher productivity with appropriate condition and it do not need special equipment.
Description
Technical field
The present invention relates to a kind of synthetic method that contains the selenoaminoacid compound, be specifically related to a kind of Animal nutrition additive amino acid---the synthetic method of selenomethionine.
Background technology
Selenium has been proved to be and has been that one of necessary nutritional trace element of animal and human's body, selenium enter body mainly by the Biogeochemistry food chain.In animal body, selenium is glutathione peroxidase, 5, and the essential part of-Tuo iodine enzyme is again simultaneously the constituent of numerous protein in the body.Statistics shows, China has 2/3 area to lack selenium approximately, only replenishes a certain amount of selenium in poultry, fowl daily ration, and therefore its ordinary production performance of competence exertion is mended selenium and produced and people's health has important meaning on all China animal.
At present, employing always replenishes the sodium selenite (NaSeO of inorganic states for poultry, fowl daily ration in the production
3) satisfying its needs, inorganic selenium also has many unfavorable factors except that utilization rate is low: 1. feed factory workman healthy had genotoxic potential; 2. toxicity is big, and animal easily poisons; 3. the same with many inorganic microelements, be difficult for by intestinal absorption, unabsorbed selenium is discharged with ight soil, contaminated environment.Further investigate already and reach common understanding for the defective people of inorganic selenium, but can not find suitable organic seleno at present again for product.Should solve and mend the selenium problem, overcome the deficiency that inorganic selenium brings again, at present to organic selenium---particularly the research of feeding organic selenium has caused domestic and international researcher's great attention.
Compare with inorganic selenium, organic selenium has following several advantage: the drip loss that 1. can reduce meat; 2. improve the animal products quality; 3. the anti-immunity that stress, improve of animal body there is important effect; 4. very high biological value and antioxygenic property are arranged; 5. strengthen the fertility of animal; 6. have characteristics such as absorptivity height, biologically active is strong, environmental pollution is little.
Present organic selenium mainly contains chemical synthesis and two kinds of methods of biofermentation obtain, the organic selenium product of chemical synthesis is a lot, as selenizing linoleic acid, selenizing lipopolysaccharides, selenide of carragheen, inositol selenic acid ester etc., these products are owing to complex manufacturing, cost an arm and a leg, except that laboratory research, the report of production application seldom.On production of fodder, the yeast selenium that is mainly at present on probation, the main bioconversion method that adopts, with the inorganic selenium sodium selenite is raw material, by biofermentation, inorganic selenium is converted into organic selenium, in yeast selenium, the citation form of organic selenium is mainly selenomethionine, and selenium exists with the reduction valence state, combines with amino acid.But also there is following several respects problem in yeast selenium: 1. Se content is very low, has only 0.03%-0.1% at present; Reach the nutritional requirements that satisfies animal, cost is very high; 2. the form of product, purity instability, quality is difficult for controlled, and the dosage of interpolation is difficult to hold; 3. complex manufacturing, the cost of investment height; 4. production efficiency is low, scale of investment is big; 5. during the fermentation, the inorganic selenium conversion ratio is low, and most of inorganic selenium is discharged with waste water formation, and environment is caused severe contamination.Therefore, the yeast selenium technology can't large-scale popularization be used.
Adopt synthetic organic selenium---the selenomethionine of chemical synthesis, mainly contain following several at present:
(1) liquid ammonia process for caustic soda purification (Na/liq NH
3) the preparation selenomethionine: prepare benzyl seleno homocysteine earlier, with sodium metal/liquefied ammonia reaction excision benzyl, methylating then obtains selenomethionine again.(Xu Huibi chief editor, the chemistry of selenium, biochemistry and the application in life science thereof, the 50th page, Wuhan: publishing house of HUST, 1994) this method is because reaction temperature is very low, and operation is extremely inconvenient, needs special device, in the large-scale industrial production, the feed metal sodium and the liquefied ammonia of use are absolutely unsafe;
(2) lithium methide method (Johannes Romer; Peter Mading; Frank Rosch.Appl.Radiat.Isot 1992,43,495-501.): in the anhydrous tetrahydro furan solvent, selenium and lithium methide reaction generate the methyl lithium selenide, derivatives reaction with 4-chloro-butyrine ester obtains selenomethionine again, this method is the lithium methide that very easily burns owing to what use, needs the anhydrous and oxygen-free device, realize that industrialization is also very difficult;
(3) amino butyrolactone hydrobromate method (Song Lianqing, Lin Yu etc., the Zhengzhou Grain College journal, 1999,20,62-64) promptly from gamma-butyrolacton, through 5 steps such as bromination, ammonia generations, yield is very low, the higher suitability for industrialized production that also is not suitable for of production cost;
(4) Dong Guochen proposes Methyleneseleno propanel method for preparing selenoic methionine (Dong Guochen, CN1369483A), promptly with methacrylaldehyde and methyl-hydroselenide addition reaction taking place earlier makes first seleno propionic aldehyde, obtain first seleno hydantoins with the Cymag cyclisation then, hydrolysis again, neutralization obtain selenomethionine, this method is also just in the laboratory research level, because this method also has following problem to need to solve: the raw material methyl-hydroselenide is difficult to obtain, and boiling point is low especially; Need use the extremely toxic substance Cymag, thereby security can not get ensureing.
(5) be that raw material prepares selenomethionine (Troels Koch, Ole Buchardt Synthesis1993,11,1065-1067 with the methionine; Wei Xuehong, Dong Guochen, CN1295214C such as Hao Junsheng),, use NaHCO then with methionine and iodomethane reaction
3Aqueous hydrolysis adds hcl acidifying, esterification obtains alpha-amido butyrolactone hydrochloride, and under nitrogen protection, heating reflux reaction is 6 hours in the sodium methyl-hydroselenide solution of alpha-amido butyrolactone hydrochloride and absolute ethyl alcohol then, cooling, acidifying, filter product.This method is totally 5 steps, and step is longer, and gross production rate is very low, the particularly reaction of alpha-amido butyrolactone hydrochloride and sodium methyl-hydroselenide, and a lot of researchs show that all yield is very low.
(6) be feedstock production selenomethionine (Otto PphlGB1281293) with dihalo ethyl piperidine diketone, still will use selenium and lithium methide prepared in reaction methyl-hydroselenide lithium salts in the method, this route also is difficult to realize suitability for industrialized production.
In a word, have following problem in the existing synthetic method: 1. the preparation of methyl-hydroselenide anion all is to adopt very easily combustion reagent lithium methide; 2. raw material sources difficulty in the route as liquefied ammonia or methyl-hydroselenide, needs special installation, and reaction condition is very harsh; 3. process route is long, yield is low, the cost height.
Summary of the invention
The purpose of this invention is to provide a kind of mild condition, easy and simple to handle, security good, cost is low, productive rate is high selenomethionine synthetic method,, satisfy the needs of organic selenium in feed addictive and other field to realize suitability for industrialized production.
The present invention is a raw material with dimethyl diselenide ether, the hydroboration metal of process hydroboration metal or its replacement reduces in alkaline aqueous solution and obtains the methyl-hydroselenide anion, again with 4-halogen-a-amino acid or derivatives thereof reaction, through hydrolysis, adjusting pH value, obtain selenomethionine, reaction equation is as follows:
Synthetic method of the present invention comprises following concrete steps:
(1) dimethyl diselenide ether is dissolved in polar non-solute, stir, the aqueous solution that adds highly basic again, the hydroboration metal that adds quantitative metallic boron hydrides or replacement in batches, wherein the diformazan diselenide is 0.5～5 with the ratio of the hydroboration metal object quality of metallic boron hydrides or replacement, 0～100 ℃ of reaction 0.5～25 hour, obtain the aqueous solution of methyl-hydroselenide salt;
(2) aqueous solution of adding 4-halogen-a-amino acid or derivatives thereof in the aqueous solution of methyl-hydroselenide salt, wherein 4-halogen-a-amino acid or derivatives thereof amount is 0.5～5 with the ratio of methyl-hydroselenide anion amount, stir, 10～100 ℃ of reactions 0.5～20 hour, after reaction finishes, hydrolysis, acidifying, be concentrated into dried, with alcohol dissolving, filtrate is regulated pH=6～7 with alkali, obtains selenomethionine.
In the above-mentioned steps (1), described polar non-solute is selected DMF, DMSO or HMPA for use, preferentially selects DMF; Described highly basic is meant hydroxide, as: KOH, NaOH, LiOH or Ba (OH)
2, preferentially select NaOH, KOH, strong base solution concentration is 1～20M, preferred 6～10M; Described metallic boron hydrides is selected NaBH for use
4, KBH
4, LiBH
4, zinc borohydride, lithium triethylborohydride or sodium cyanoborohydride, preferentially select NaBH
4, KBH
4
In the above-mentioned steps (2), described 4-halogen-a-amino acid or derivatives thereof specifically refers to following two types:
When 1. Y was H, structural formula was as follows:
X:C1, Br, I preferentially select Cl, Br;
R:H, C
1-C
4Alkyl, as methyl, ethyl, propyl group, butyl, preferentially select methyl, ethyl;
When 2. Y was acyl group, structural formula was as follows:
X:Cl, Br, I preferentially select Cl, Br;
R:H, C
1-C
4Alkyl, as methyl, ethyl, propyl group, butyl, preferentially select methyl, ethyl;
R
1: H, C
1-C
3Alkyl, as methyl, ethyl, propyl group, preferentially select methyl, ethyl;
Described acid is meant rare strong acid solution, as: HCl, H
2SO
4Or HNO
3, preferentially select HCl, H
2SO
4, the concentration of acid is 0.1M～6M, preferentially selects 1～3M; Described alcohol is C
1-C
4Monohydric alcohol and dihydroxylic alcohols, as methyl alcohol, ethanol, 1-propyl alcohol, 2-propyl alcohol, 1-butanols, 2-butanols, ethylene glycol etc., also refer to glycerine in addition, preferentially select methyl alcohol, ethanol; Described alkali is ammoniacal liquor and organic amine, as dimethylamine, trimethylamine, ethamine, diethylamine, triethylamine, propylamine etc., preferentially selects triethylamine, ammoniacal liquor.
It is raw material that the present invention proposes with dimethyl diselenide ether, in the aqueous solution of alkali, obtain the methyl-hydroselenide anion through borohydride reduction agent reduction, again with the reactant aqueous solution of 4-halogen-a-amino acid or derivatives thereof, hydrolysis, acidifying, the two-step reaction method of regulating pH=6～7 prepares selenomethionine.Reaction system of the present invention all is to carry out in the aqueous solution, and reaction system does not need inert gas shielding, avoids anhydrous, oxygen free operation; What use in the reaction all is common raw material, and security is good; Do not need the characteristics of special device, reaction condition gentleness, easy operating, productive rate higher (55%～75%), be easy to carry out suitability for industrialized production.
The specific embodiment
The present invention will be described below to enumerate specific embodiment.Embodiment only is used for that the invention will be further described, does not represent protection scope of the present invention, and nonessential modification and adjustment that other people make according to the present invention still belong to protection scope of the present invention.
Embodiment 1
In the 500ml reaction bulb, add 50g CH
3SeSeCH
3, add the 20mlDMSO dilution, under agitation adding 100ml concentration is the 6M NaOH aqueous solution, holding temperature adds the NaBH that total amount is 6g at 25 ℃ in batches
4, fully stirring reaction is 5 hours, obtains clear solution.
In above-mentioned gained solution, add 35g 4-bromo-butyrine methyl esters hydrobromate, heat up 60 ℃ stirring reaction 3 hours, after reaction finishes, add the hcl acidifying of 3M, be concentrated into dried, with the ethanol dissolving, filter, collect filtrate, regulate pH=6～7 with ammoniacal liquor, filter, washing, drying obtains the selenomethionine 14.85g of metallic luster, productive rate 60%, HPLC content analysis 98%, the content 38.5% of selenium.
Embodiment 2
In the 1000ml reaction bulb, add 150g CH
3SeSeCH
3, add 100ml DMF dilution, under agitation adding 300ml concentration is the 8M KOH aqueous solution, holding temperature adds the KBH that total amount is 64.5g at 60 ℃ in batches
4, fully stirring reaction is 4 hours, obtains clear solution.
In above-mentioned gained solution, add 135g 4-chloro-α-(N-acetyl group) aminobutyric acid methyl esters, heat up 40 ℃ stirring reaction 8 hours; after reaction finishes, add the hcl acidifying of 2M, be concentrated into dried; with the ethanol dissolving, filter, collect filtrate; regulate pH=6～7 with ammoniacal liquor, filter, washing; drying obtains the selenomethionine 75.2g of metallic luster; productive rate 55%, HPLC content analysis 97%, the content 38.0% of selenium.
Embodiment 3
In the 50ml reaction bulb, add 5g CH
3SeSeCH
3, add 5ml HMPA dilution, under agitation adding 10ml concentration is the 1M NaOH aqueous solution, holding temperature adds the NaBH that total amount is 0.6g at 20 ℃ in batches
4, fully stirring reaction is 10 hours, obtains clear solution.
In above-mentioned gained solution, add 7g 4-bromo-butyrine hydrobromate, heat up 50 ℃ stirring reaction 5 hours, after reaction finishes, add the hcl acidifying of 3M, be concentrated into dried, with the ethanol dissolving, filter, collect filtrate, regulate pH=6～7 with ammoniacal liquor, filter, washing, drying obtains the selenomethionine 3.18g of metallic luster, productive rate 61%, HPLC content analysis 98%, the content 38.5% of selenium.
Embodiment 4
In the 500ml reaction bulb, add 50g CH
3SeSeCH
3, add 20ml DMF dilution, under agitation adding 50ml concentration is the 20M NaOH aqueous solution, holding temperature adds the NaBH that total amount is 6g at 40 ℃ in batches
4, fully stirring reaction is 5 hours, obtains clear solution.
In above-mentioned gained solution, add 95g 4-iodo-butyrine methyl esters hydriodate, heat up 50 ℃ stirring reaction 7 hours, after reaction finishes, add the hcl acidifying of 6M, be concentrated into dried, with the ethanol dissolving, filter, collect filtrate, regulate pH=6～7 with triethylamine, filter, washing, drying obtains the selenomethionine 39.15g of metallic luster, productive rate 75%, HPLC content analysis 96%, the content 37.9% of selenium.
Embodiment 5
In the 250ml reaction bulb, add 10g CH
3SeSeCH
3, add the 10mlDMF dilution, under agitation adding 20ml concentration is the 8M NaOH aqueous solution, holding temperature adds the NaBH that total amount is 2g at 30 ℃ in batches
4, fully stirring reaction is 4 hours, obtains clear solution.
In above-mentioned gained solution, add 25g 4-bromo-α-(N-acetyl group) aminobutyric acid methyl esters, heat up 60 ℃ stirring reaction 3 hours; after reaction finishes, add the hcl acidifying of 3M, be concentrated into dried; with the ethanol dissolving, filter, collect filtrate; regulate pH=6～7 with ammoniacal liquor, filter, washing; drying obtains the selenomethionine 12g of metallic luster; productive rate 58.5%, HPLC content analysis 98.2%, the content 38.6% of selenium.
Claims (9)
1, a kind of Animal nutrition additive amino acid---the synthetic method of selenomethionine, it is characterized in that with dimethyl diselenide ether be raw material, the hydroboration metal of process hydroboration metal or its replacement reduces in alkaline aqueous solution and obtains the methyl-hydroselenide anion, again with 4-halogen-a-amino acid or derivatives thereof reaction, through hydrolysis, adjusting pH value, obtain selenomethionine.
2, the synthetic method of selenomethionine according to claim 1 is characterized in that comprising following concrete steps:
(1) dimethyl diselenide ether is dissolved in polar non-solute, stir, the aqueous solution that adds highly basic again, the hydroboration metal that adds quantitative metallic boron hydrides or replacement in batches, wherein the diformazan diselenide is 0.5～5 with the ratio of the hydroboration metal object quality of metallic boron hydrides or replacement, 0～100 ℃ of reaction 0.5～25 hour, obtain the aqueous solution of methyl-hydroselenide salt;
(2) aqueous solution of adding 4-halogen-a-amino acid or derivatives thereof in the aqueous solution of methyl-hydroselenide salt, wherein 4-halogen-a-amino acid or derivatives thereof amount is 0.5～5 with the ratio of methyl-hydroselenide anion amount, stirs, 10～100 ℃ of reactions 0.5～20 hour, after reaction finishes, hydrolysis, acidifying is concentrated into dried, dissolve with alcohol, filtrate is regulated pH=6～7 with alkali, obtains selenomethionine, and reaction equation is as follows:
3, the synthetic method of selenomethionine according to claim 2 is characterized in that the polar non-solute described in the step (1) is DMF, DMSO or HMPA.
4, the synthetic method of selenomethionine according to claim 2 is characterized in that the highly basic described in the step (1) is KOH, NaOH, LiOH or Ba (OH)
2, its concentration is 1～20M.
5, the synthetic method of selenomethionine according to claim 2 is characterized in that the metallic boron hydrides described in the step (1) is NaBH
4, KBH
4, LiBH
4, zinc borohydride, lithium triethylborohydride or sodium cyanoborohydride.
6, the synthetic method of selenomethionine according to claim 2 is characterized in that the 4-halogen-a-amino acid or derivatives thereof described in the step (2) specifically refers to following two types:
When 1. Y was H, structural formula was as follows:
Wherein, X:Cl, Br, I;
R:H, C
1-C
4Alkyl;
When 2. Y was acyl group, structural formula was as follows:
Wherein, X:Cl, Br, I;
R:H, C
1-C
4Alkyl;
R
1: H, C
1-C
3Alkyl.
7, the synthetic method of selenomethionine according to claim 2 is characterized in that the acid described in the step (2) is HCl, H
2SO
4Or HNO
3, its concentration is 0.1～6M.
8, the synthetic method of selenomethionine according to claim 2 is characterized in that the alcohol described in the step (2) is C
1-C
4Monohydric alcohol or dihydroxylic alcohols.
9, the synthetic method of selenomethionine according to claim 2 is characterized in that the alkali described in the step (2) is ammoniacal liquor or organic amine.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105294528A (en) * | 2015-11-26 | 2016-02-03 | 成都百事兴科技实业有限公司 | Preparation method for L-selenocysteine |
| CN113698331A (en) * | 2020-05-23 | 2021-11-26 | 普济生物科技（台州）有限公司 | Synthetic method of L-selenium-methyl selenocysteine |
| CN113773229A (en) * | 2021-09-03 | 2021-12-10 | 西安交通大学 | Alpha, beta-unsaturated amino acid derivative and DL-selenium-methyl seleno amino acid derivative thereof, synthetic method and application |
| CN115677548A (en) * | 2022-11-16 | 2023-02-03 | 湖南农业大学 | High-efficiency synthesis method of selenomethionine |
-
2007
- 2007-06-21 CN CNA2007100287340A patent/CN101073378A/en active Pending
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105294528A (en) * | 2015-11-26 | 2016-02-03 | 成都百事兴科技实业有限公司 | Preparation method for L-selenocysteine |
| CN113698331A (en) * | 2020-05-23 | 2021-11-26 | 普济生物科技（台州）有限公司 | Synthetic method of L-selenium-methyl selenocysteine |
| CN113698331B (en) * | 2020-05-23 | 2023-12-15 | 普济生物科技（台州）有限公司 | Synthesis method of L-selenium-methyl selenocysteine |
| CN113773229A (en) * | 2021-09-03 | 2021-12-10 | 西安交通大学 | Alpha, beta-unsaturated amino acid derivative and DL-selenium-methyl seleno amino acid derivative thereof, synthetic method and application |
| CN115677548A (en) * | 2022-11-16 | 2023-02-03 | 湖南农业大学 | High-efficiency synthesis method of selenomethionine |
| CN115677548B (en) * | 2022-11-16 | 2024-04-09 | 湖南农业大学 | Efficient synthesis method of selenomethionine |
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