CN108218732A - A kind of preparation method of low cost high security l-carnitine - Google Patents
A kind of preparation method of low cost high security l-carnitine Download PDFInfo
- Publication number
- CN108218732A CN108218732A CN201810235376.9A CN201810235376A CN108218732A CN 108218732 A CN108218732 A CN 108218732A CN 201810235376 A CN201810235376 A CN 201810235376A CN 108218732 A CN108218732 A CN 108218732A
- Authority
- CN
- China
- Prior art keywords
- carnitine
- preparation
- reaction
- compound
- high security
- 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.)
- Pending
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C227/00—Preparation of compounds containing amino and carboxyl groups bound to the same carbon skeleton
- C07C227/14—Preparation of compounds containing amino and carboxyl groups bound to the same carbon skeleton from compounds containing already amino and carboxyl groups or derivatives thereof
- C07C227/18—Preparation of compounds containing amino and carboxyl groups bound to the same carbon skeleton from compounds containing already amino and carboxyl groups or derivatives thereof by reactions involving amino or carboxyl groups, e.g. hydrolysis of esters or amides, by formation of halides, salts or esters
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C227/00—Preparation of compounds containing amino and carboxyl groups bound to the same carbon skeleton
- C07C227/04—Formation of amino groups in compounds containing carboxyl groups
- C07C227/06—Formation of amino groups in compounds containing carboxyl groups by addition or substitution reactions, without increasing the number of carbon atoms in the carbon skeleton of the acid
- C07C227/08—Formation of amino groups in compounds containing carboxyl groups by addition or substitution reactions, without increasing the number of carbon atoms in the carbon skeleton of the acid by reaction of ammonia or amines with acids containing functional groups
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C227/00—Preparation of compounds containing amino and carboxyl groups bound to the same carbon skeleton
- C07C227/14—Preparation of compounds containing amino and carboxyl groups bound to the same carbon skeleton from compounds containing already amino and carboxyl groups or derivatives thereof
- C07C227/16—Preparation of compounds containing amino and carboxyl groups bound to the same carbon skeleton from compounds containing already amino and carboxyl groups or derivatives thereof by reactions not involving the amino or carboxyl groups
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/584—Recycling of catalysts
Abstract
The present invention relates to a kind of preparation method of biostearin nutrient, more particularly, to a kind of preparation method of inexpensive high security L carnitines.It mainly solves unstable product quality for preparing L carnitines present in the prior art, has used the chemicals cyanide of severe toxicity, has there is certain danger in production, and the technical issues of production cost higher grade.The present invention adds in chloro ethyl acetoacetate and absolute ethyl alcohol in high-pressure reactor, is passed through front three amine gas, adds compound（Ⅲ）, catalyst and methanol times, after stirring evenly with hydrogen displacement three times, recycle catalyst, compound be obtained by filtration（Ⅱ）, in the reactor, add in compound（Ⅱ）And sodium hydroxide solution, back flow reaction is heated under then stirring, after completion of the reaction, obtains the aqueous slkali of L carnitine crude products, is handled using cation exchange resin and removes impurity, the aqueous solution of L carnitines is obtained, L carnitines is obtained after concentration, vacuum drying（Ⅰ）Fine work.
Description
Technical field
The present invention relates to a kind of preparation method of biostearin nutrient, more particularly, to a kind of inexpensive high security L-
The preparation method of carnitine.
Background technology
L-carnitine is a kind of biostearin nutrient with extensive physiological activity as a kind of inner salt of amino acid, L-
Carnitine is a kind of substance of key in fat metabolic process, and aliphatic acid can be promoted to enter mitochondrial oxidation decomposition.It may be said that
L-carnitine is to transport the carrier of aliphatic acid.In long-time strenuous exercise, l-carnitine improves the oxidation rate of fat, reduces
The consumption of glycogen, while also delayed fatigue.At present, l-carnitine has been applied to the fields such as medicine, health care and food, and by
Switzerland, France, the U.S. and the World Health Organization are defined as legal multipurpose nutritive agent.
At present, the chemical synthesis and preparation method main preparation methods of l-carnitine are as follows：One kind is by γ-chloroethene ethyl acetoacetic acid
Prepared by the methods of ethyl ester asymmetric catalytic hydrogenation or 3- bromopropene Asymmetrical dihydroxylations, the product that such method is prepared
Quality is unstable, it is difficult to form preferable competitiveness on the market；It is another kind of that epoxychloropropane is used first to be prepared for starting material
L- (-) -3- chlorine-2-hydroxyl propyl trimethyl ammonium chlorides, then by hydrogenation, hydrolyze and l-carnitine is made, but used in this method
The chemicals cyanide of severe toxicity, has certain danger, and higher requirement is proposed to production management in production.
Invention content
The present invention is to provide a kind of preparation method of inexpensive high security l-carnitine, mainly solves prior art institute
The existing unstable product quality for preparing l-carnitine, has used the chemicals cyanide of severe toxicity, has there is certain danger in production
It is dangerous, and production cost it is higher wait the technical issues of.
The above-mentioned technical problem of the present invention is mainly what is be addressed by following technical proposals：
The preparation method of a kind of inexpensive high security l-carnitine of the present invention, it is characterised in that the method includes：
The reaction equation of l-carnitine is：
A. the preparation of compound (III)：
The chloro ethyl acetoacetate of 1 parts by weight and the absolute ethyl alcohol of 5-10 parts by weight are added in high-pressure reactor, is stirred
Be passed through front three amine gas after mixing uniformly, it is 0.5-0.6MPa to keep pressure in kettle, is then heated up, during which in kettle pressure after heating
Declined, discontinuity supplement front three amine gas, until pressure is maintained at 0.5-0.6MPa and no longer declines, stirring is fully anti-
Should, after reaction, normal pressure state is down to, air-distillation removes half solvent, refilters the quarternary ammonium salt compound for collecting generation
(III), it can be directly used for reacting in next step；
B. the preparation of compound (II)：
Added in high-pressure reactor the compounds (III) of 1 parts by weight, 0.04-0.06 parts by weight catalyst two [(S)-
The methanol of (+) -5,5 '-bis- (diphenylphosphine) -4,4 '-bis- -1,3-, bis- oxygroup benzene times and 4-8 parts by weight again, is used after stirring evenly
Hydrogen is replaced three times, then it is 4-6MPa to be passed through hydrogen to keep pressure, and heating is stirred to react, and is down to normal pressure after reaction, is filtered
Catalyst is recycled, air-distillation removes most of solvent postcooling stirring, then stands, the solid of precipitation is collected by filtration, to change
Object (II) is closed, can be directly used for reacting in next step；
The preparation of c.L- carnitines (I)：
In the reactor, the compound (II) of 1 parts by weight of addition and a concentration of 5% sodium hydroxide of 4-8 parts by weight are molten
Liquid is heated to back flow reaction under then stirring, after completion of the reaction, obtains the aqueous slkali of l-carnitine crude product, is handed over using cation
It changing resin treatment and removes impurity, obtain the aqueous solution of l-carnitine, the pale solid obtained after concentration is recrystallized with absolute ethyl alcohol,
White solid, as l-carnitine (I) fine work are obtained after vacuum drying.
The present invention is directly using chloro ethyl acetoacetate as raw material, after the trimethylamine with gas is reacted, choosing
Selecting property is fine, and side reaction is fewer, and the service efficiency of trimethylamine can be improved using gas trimethylamine.Meanwhile pass of the invention
Key innovates the catalyst choice for being reduction step, and ordinary circumstance carbonyl reduction selects stronger inorganic salts reducing agent (hydroboration
Sodium etc.), but inorganic salts reducing agent is used on the one hand easily to generate inorganic salts impurity, secondly because molecular structure contains quaternary ammonium
Salt and ester group structure, the selectivity of inorganic salts reducing agent reduction reaction is bad, and yield is relatively low, using special catalyst hydrogenation also
Original, high-efficiency cleaning, and catalyst type is more, we by having attempted a variety of different types of catalyst, just determine effect compared with
Good kind.
Preferably, the step a is warming up to 110-130 DEG C after being passed through front three amine gas, reaction time 6-10 hour.
Preferably, the step b is warming up to 50-60 DEG C after being passed through hydrogen, it is stirred to react 4-6 hours.
It is stirred 20-40 minutes to 0-3 DEG C preferably, the step b air-distillations remove most of solvent postcooling.
Preferably, being heated to 50-60 DEG C of back flow reaction in the step c 5-10 hours.
Therefore, technics comparing is ripe at home for the raw material chloro ethyl acetoacetate that the present invention uses, and derives from a wealth of sources, supplies
Abundance, and price is suitable, can effectively control production cost, and reaction route of the present invention is short, and each yield that walks is considerable, obtains
L-carnitine finished product it is more.
Specific embodiment
Below by embodiment, the technical solutions of the present invention will be further described.
Embodiment 1：A kind of preparation method of inexpensive high security l-carnitine of this example, step are：
The reaction equation of l-carnitine is：
A. the preparation of compound (III)：
Chloro ethyl acetoacetate (164.5g, 1.0mol) and absolute ethyl alcohol (1640g) are added in high-pressure reactor, is stirred
Front three amine gas is passed through after mixing uniformly, it is 0.6MPa to keep pressure in kettle, is then warming up to 120 DEG C again, during which pressure exists in kettle
Declined after heating, discontinuity supplement front three amine gas until pressure is maintained at 0.6MPa and no longer declines, is then kept
It is stirred to react under this temperature and pressure state 10 hours, after reaction, is down to normal pressure state, it is semi-soluble that air-distillation removes one
Agent refilters the quarternary ammonium salt compound (III) for collecting generation, and it is 205.3g to be weighed after dry, and yield about 91.9% can be used directly
It is reacted in next step；
B. the preparation of compound (II)：
Added in high-pressure reactor compound (III) (223.5g, 1.0mol), catalyst two [(S)-(+) -5,5 '-bis-
(diphenylphosphine) -4,4 '-bis- -1,3-, bis- oxygroup benzene (13.4g) and methanol (1750g), after stirring evenly with hydrogen displacement three times,
It is 6MPa to be passed through hydrogen again and keep pressure, is warming up to 50-60 DEG C, is stirred to react 6 hours, is down to normal pressure after reaction, filters
Recycle catalyst, air-distillation removes most of solvent postcooling and stirs 30 minutes to 0 DEG C, then stands overnight, is collected by filtration
The solid of precipitation is compound (II), and it is 202.3g to be weighed after dry, and yield is about 89.7%.It can be directly used for anti-in next step
It should；
The preparation of c.L- carnitines (I)：
In the reactor, compound (II) (225.5g, 1.0mol) and a concentration of 5% sodium hydroxide solution are added in
(1800g) is heated to back flow reaction 10 hours under then stirring, after completion of the reaction, obtains the aqueous slkali of l-carnitine crude product, then pass through
It crosses cation exchange resin processing and removes impurity, obtain the aqueous solution of l-carnitine, the pale solid obtained after concentration is with anhydrous
Ethyl alcohol recrystallization obtains white solid after vacuum drying, is l-carnitine fine work (I), for 131.4g, yield about 81.6%.[α]
20D=-30.9 detects its quality index through HPLC and meets the requirement of United States Pharmacopeia USP (28) version.
Embodiment 2：A kind of preparation method of inexpensive high security l-carnitine of this example, other steps and 1 phase of embodiment
Together, only the preparation method of the compound (III) of step A is as follows：
Chloro ethyl acetoacetate (164.5g, 1.0mol) and absolute ethyl alcohol (825g) are added in high-pressure reactor, is stirred
Front three amine gas is passed through after mixing uniformly, it is 0.5MPa to keep pressure in kettle, is then warming up to 120 DEG C again, during which pressure exists in kettle
Declined after heating, discontinuity supplement front three amine gas until pressure is maintained at 0.5MPa and no longer declines, is then kept
It is stirred to react under this temperature and pressure state 6 hours, after reaction, is down to normal pressure state, it is semi-soluble that air-distillation removes one
Agent refilters the quarternary ammonium salt compound (III) for collecting generation, and it is 180.2g to be weighed after dry, and yield about 80.6% can be used directly
It is reacted in next step.
Embodiment 3：A kind of preparation method of inexpensive high security l-carnitine of this example, other steps and 1 phase of embodiment
Together, only the preparation method of the compound (III) of step A is as follows：
Chloro ethyl acetoacetate (164.5g, 1.0mol) and absolute ethyl alcohol (1100g) are added in high-pressure reactor, is stirred
Front three amine gas is passed through after mixing uniformly, it is 0.6MPa to keep pressure in kettle, is then warming up to 120 DEG C again, during which pressure exists in kettle
Declined after heating, discontinuity supplement front three amine gas until pressure is maintained at 0.6MPa and no longer declines, is then kept
It is stirred to react under this temperature and pressure state 8 hours, after reaction, is down to normal pressure state, it is semi-soluble that air-distillation removes one
Agent refilters the quarternary ammonium salt compound (III) for collecting generation, and it is 196.7g to be weighed after dry, and yield about 88.0% can be used directly
It is reacted in next step.
Embodiment 4：A kind of preparation method of inexpensive high security l-carnitine of this example, other steps and 1 phase of embodiment
Together, only the preparation method of the compound (II) of step B is as follows：
Added in high-pressure reactor compound (III) (223.5g, 1.0mol), catalyst two [(S)-(+) -5,5 '-bis-
(diphenylphosphine) -4,4 '-bis- -1,3-, bis- oxygroup benzene (9g) and methanol (900g) after stirring evenly with hydrogen displacement three times, then lead to
It is 4MPa to enter hydrogen to keep pressure, is warming up to 50-60 DEG C, is stirred to react 4 hours, is down to normal pressure after reaction, is recovered by filtration
Catalyst, air-distillation remove most of solvent postcooling and stir 30 minutes to 0 DEG C, then stand overnight, precipitation is collected by filtration
Solid, be compound (II), weighed after dry as 167.6g, yield is about 74.3%.It can be directly used for reacting in next step.
Embodiment 5：A kind of preparation method of inexpensive high security l-carnitine of this example, other steps and 1 phase of embodiment
Together, only the preparation method of the compound (II) of step B is as follows：
Added in high-pressure reactor compound (III) (223.5g, 1.0mol), catalyst two [(S)-(+) -5,5 '-bis-
(diphenylphosphine) -4,4 '-bis- -1,3-, bis- oxygroup benzene (11g) and methanol (1200g), after stirring evenly with hydrogen displacement three times, then
It is 5MPa to be passed through hydrogen and keep pressure, is warming up to 50-60 DEG C, is stirred to react 5 hours, is down to normal pressure after reaction, filters back
Receive catalyst, air-distillation removes most of solvent postcooling and stirs 30 minutes to 0 DEG C, then stands overnight, analysis is collected by filtration
The solid gone out is compound (II), and it is 183.9g to be weighed after dry, and yield is about 81.6%.It can be directly used for reacting in next step.
Embodiment 6：A kind of preparation method of inexpensive high security l-carnitine of this example, other steps and 1 phase of embodiment
Together, only the preparation method of the l-carnitine (I) of step C is as follows：
In the reactor, compound (II) (225.5g, 1.0mol) and a concentration of 5% sodium hydroxide solution are added in
(905g) is heated to back flow reaction 5 hours under then stirring, after completion of the reaction, obtains the aqueous slkali of l-carnitine crude product, using
Cation exchange resin processing removes impurity, obtains the aqueous solution of l-carnitine, the anhydrous second of the pale solid obtained after concentration
Alcohol recrystallizes, and white solid is obtained after vacuum drying, is l-carnitine fine work (I), for 102.6g, yield about 63.7%.[α]20D
=-31.1 detect its quality index through HPLC and meet the requirement of United States Pharmacopeia USP (28) version.
Embodiment 7：A kind of preparation method of inexpensive high security l-carnitine of this example, other steps and 1 phase of embodiment
Together, only the preparation method of the l-carnitine (I) of step C is as follows：
In the reactor, compound (II) (225.5g, 1.0mol) and a concentration of 5% sodium hydroxide solution are added in
(1200g) is heated to back flow reaction 6 hours under then stirring, after completion of the reaction, obtains the aqueous slkali of l-carnitine crude product, then pass through
It crosses cation exchange resin processing and removes impurity, obtain the aqueous solution of l-carnitine, the pale solid obtained after concentration is with anhydrous
Ethyl alcohol recrystallization obtains white solid after vacuum drying, is l-carnitine fine work (I), for 112.4g, yield about 69.8%.[α]
20D=-31.0 detects its quality index through HPLC and meets the requirement of United States Pharmacopeia USP (28) version.
Embodiment 8：A kind of preparation method of inexpensive high security l-carnitine of this example, other steps and 1 phase of embodiment
Together, only the preparation method of the l-carnitine (I) of step C is as follows：
In the reactor, compound (II) (225.5g, 1.0mol) and a concentration of 5% sodium hydroxide solution are added in
(1350g) is heated to back flow reaction 8 hours under then stirring, after completion of the reaction, obtains the aqueous slkali of l-carnitine crude product, then pass through
It crosses cation exchange resin processing and removes impurity, obtain the aqueous solution of l-carnitine, the pale solid obtained after concentration is with anhydrous
Ethyl alcohol recrystallization obtains white solid after vacuum drying, is l-carnitine fine work (I), for 119.7g, yield about 74.3%.[α]
20D=-30.8 detects its quality index through HPLC and meets the requirement of United States Pharmacopeia USP (28) version.
Structure feature the foregoing is merely specific embodiments of the present invention, but the present invention is not limited thereto, Ren Heben
The technical staff in field in the field of the invention, all cover among the scope of the claims of the present invention by the variation or modification made.
Claims (5)
1. a kind of preparation method of low cost high security l-carnitine, it is characterised in that the method includes：
The reaction equation of l-carnitine is：
A. the preparation of compound (III)：
The chloro ethyl acetoacetate of 1 parts by weight and the absolute ethyl alcohol of 5-10 parts by weight are added in high-pressure reactor, stirring is equal
Be passed through front three amine gas after even, it is 0.5-0.6MPa to keep pressure in kettle, is then heated up, during which in kettle pressure after heating
Declining, discontinuity supplement front three amine gas until pressure is maintained at 0.5-0.6MPa and no longer declines, stirs fully reaction,
After reaction, normal pressure state is down to, air-distillation removes half solvent, refilters the quarternary ammonium salt compound for collecting generation
(III), it can be directly used for reacting in next step；
B. the preparation of compound (II)：
Added in high-pressure reactor the compounds (III) of 1 parts by weight, 0.04-0.06 parts by weight catalyst two [(S)-(+)-
The methanol of 5,5 '-bis- (diphenylphosphine) -4,4 '-bis- -1,3-, bis- oxygroup benzene times and 4-8 parts by weight again, hydrogen is used after stirring evenly
It replaces three times, then it is 4-6MPa to be passed through hydrogen to keep pressure, heating is stirred to react, is down to normal pressure after reaction, is recovered by filtration
Catalyst, air-distillation remove most of solvent postcooling stirring, then stand, the solid of precipitation is collected by filtration, and are compound
(II), it can be directly used for reacting in next step；
The preparation of c.L- carnitines (I)：
In the reactor, the compound (II) of 1 parts by weight and a concentration of 5% sodium hydroxide solution of 4-8 parts by weight are added in, so
Back flow reaction is heated under stirring afterwards, after completion of the reaction, the aqueous slkali of l-carnitine crude product is obtained, using cation exchange resin
Processing removes impurity, obtains the aqueous solution of l-carnitine, the pale solid obtained after concentration is recrystallized with absolute ethyl alcohol, and vacuum is done
White solid, as l-carnitine (I) fine work are obtained after dry.
2. the preparation method of a kind of inexpensive high security l-carnitine according to claim 1, it is characterised in that described
Step a is warming up to 110-130 DEG C after being passed through front three amine gas, reaction time 6-10 hour.
3. the preparation method of a kind of inexpensive high security l-carnitine according to claim 1, it is characterised in that described
Step b is warming up to 50-60 DEG C after being passed through hydrogen, is stirred to react 4-6 hours.
4. the preparation method of a kind of inexpensive high security l-carnitine according to claim 1, it is characterised in that described
Step b air-distillations remove most of solvent postcooling and stir 20-40 minutes to 0-3 DEG C.
5. the preparation method of a kind of inexpensive high security l-carnitine according to claim 1, it is characterised in that described
50-60 DEG C of back flow reaction is heated in step c 5-10 hours.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810235376.9A CN108218732A (en) | 2018-03-21 | 2018-03-21 | A kind of preparation method of low cost high security l-carnitine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810235376.9A CN108218732A (en) | 2018-03-21 | 2018-03-21 | A kind of preparation method of low cost high security l-carnitine |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN108218732A true CN108218732A (en) | 2018-06-29 |
Family
ID=62658952
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810235376.9A Pending CN108218732A (en) | 2018-03-21 | 2018-03-21 | A kind of preparation method of low cost high security l-carnitine |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108218732A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108902465A (en) * | 2018-07-18 | 2018-11-30 | 安徽安宠宠物用品有限公司 | A kind of fat dog extruding grain and preparation method thereof being added to l-carnitine |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4021480A (en) * | 1974-09-25 | 1977-05-03 | Lonza Ltd. | Process for the production of carnitine |
| CN1727328A (en) * | 2004-07-28 | 2006-02-01 | 香港理工大学 | Method for preparing L-carnitine |
| WO2009038656A1 (en) * | 2007-09-17 | 2009-03-26 | Kosta Steliou | Mitochondria-targeting antioxidant therapeutics |
| CN102633664A (en) * | 2012-03-30 | 2012-08-15 | 广西新晶科技有限公司 | Preparation method of L-carnitine |
| CN103012177A (en) * | 2012-12-17 | 2013-04-03 | 苏州浩波科技股份有限公司 | L-carnitine preparation method |
-
2018
- 2018-03-21 CN CN201810235376.9A patent/CN108218732A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4021480A (en) * | 1974-09-25 | 1977-05-03 | Lonza Ltd. | Process for the production of carnitine |
| CN1727328A (en) * | 2004-07-28 | 2006-02-01 | 香港理工大学 | Method for preparing L-carnitine |
| WO2009038656A1 (en) * | 2007-09-17 | 2009-03-26 | Kosta Steliou | Mitochondria-targeting antioxidant therapeutics |
| CN102633664A (en) * | 2012-03-30 | 2012-08-15 | 广西新晶科技有限公司 | Preparation method of L-carnitine |
| CN103012177A (en) * | 2012-12-17 | 2013-04-03 | 苏州浩波科技股份有限公司 | L-carnitine preparation method |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108902465A (en) * | 2018-07-18 | 2018-11-30 | 安徽安宠宠物用品有限公司 | A kind of fat dog extruding grain and preparation method thereof being added to l-carnitine |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103476741B (en) | Method for producing aqueous solutions of methylglycine-N,N-diacetic acid trialkali metal salts | |
| CN103664665A (en) | Solid sodium sarcosine preparation method | |
| CN102516105B (en) | Preparation method of L-carnitine hydrochloride | |
| CN109400556A (en) | A kind of synthetic method of D- (-)-pantoic acid lactone | |
| US8680329B2 (en) | Process for preparation of α-ketoglutaric acid | |
| CN107325015B (en) | Method for continuously preparing glycine from hydroxyacetonitrile | |
| CN108218732A (en) | A kind of preparation method of low cost high security l-carnitine | |
| CN114524738A (en) | Glycine preparation method for reducing iminodiacetic acid content | |
| US8754256B2 (en) | Process for preparation of L-Arginine α-ketoglutarate 1:1 and 2:1 | |
| CN108033903A (en) | Synthesis process for D L-p-methylsulfonylphenylserine ethyl ester with water esterification | |
| CN101186587B (en) | Method for synthesizing derivative of beta-amino acid and intermediate product thereof | |
| CN106397357B (en) | A kind of preparation method of Trimetazidine Hydrochloride | |
| CN100516025C (en) | Method for synthesizing D-norvaline using n-pentanoic acid | |
| CN102898338A (en) | Alpha-amino acid chromium (III) chelate and preparation method thereof | |
| CN108017561A (en) | A kind of method of refined card glutamic acid | |
| CN105906520A (en) | Recycling method and application of L-methyldopa intermediate | |
| CN102584636A (en) | Synthetic method of kreatine | |
| CN101591255B (en) | Clean production process of iminodiacetic acid | |
| US20020192336A1 (en) | Preparation of metal complexes of amino acids obtained by hydrolysis of soy protein | |
| Shiraiwa et al. | Asymmetric transformation of (RS)-cysteine via formation of (RS)-4-thiazolidinecarboxylic acids | |
| JPH0393753A (en) | Production of alpha-amino acid | |
| CN113999171A (en) | Synthesis method of high-content dipyrithione | |
| CN105524107B (en) | A kind of PMIDA clean manufacturing and accessory substance novel process for recycling | |
| CN102827014B (en) | Preparation method of L(-)-carnitine | |
| JPH0393757A (en) | Production of alpha-amino acid |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20180629 |
|
| RJ01 | Rejection of invention patent application after publication |