JPH0749397B2 - Method for racemization of optically active serine - Google Patents
Method for racemization of optically active serineInfo
- Publication number
- JPH0749397B2 JPH0749397B2 JP12260787A JP12260787A JPH0749397B2 JP H0749397 B2 JPH0749397 B2 JP H0749397B2 JP 12260787 A JP12260787 A JP 12260787A JP 12260787 A JP12260787 A JP 12260787A JP H0749397 B2 JPH0749397 B2 JP H0749397B2
- Authority
- JP
- Japan
- Prior art keywords
- serine
- reaction
- optically active
- racemization
- active serine
- 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.)
- Expired - Lifetime
Links
- MTCFGRXMJLQNBG-UHFFFAOYSA-N Serine Natural products OCC(N)C(O)=O MTCFGRXMJLQNBG-UHFFFAOYSA-N 0.000 title claims description 38
- 238000000034 method Methods 0.000 title claims description 27
- 230000006340 racemization Effects 0.000 title description 9
- 239000007864 aqueous solution Substances 0.000 claims description 14
- 238000010438 heat treatment Methods 0.000 claims description 4
- MTCFGRXMJLQNBG-REOHCLBHSA-N (2S)-2-Amino-3-hydroxypropansäure Chemical compound OC[C@H](N)C(O)=O MTCFGRXMJLQNBG-REOHCLBHSA-N 0.000 description 32
- 238000006243 chemical reaction Methods 0.000 description 29
- 229960001153 serine Drugs 0.000 description 29
- 239000000243 solution Substances 0.000 description 11
- 239000013078 crystal Substances 0.000 description 7
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 6
- 230000035484 reaction time Effects 0.000 description 6
- DHMQDGOQFOQNFH-UHFFFAOYSA-N Glycine Chemical compound NCC(O)=O DHMQDGOQFOQNFH-UHFFFAOYSA-N 0.000 description 4
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 4
- 238000003756 stirring Methods 0.000 description 4
- 239000000126 substance Substances 0.000 description 4
- WFDIJRYMOXRFFG-UHFFFAOYSA-N Acetic anhydride Chemical compound CC(=O)OC(C)=O WFDIJRYMOXRFFG-UHFFFAOYSA-N 0.000 description 3
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 3
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 229910052757 nitrogen Inorganic materials 0.000 description 3
- 230000003287 optical effect Effects 0.000 description 3
- 239000002994 raw material Substances 0.000 description 3
- 150000003839 salts Chemical class 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- WSFSSNUMVMOOMR-UHFFFAOYSA-N Formaldehyde Chemical compound O=C WSFSSNUMVMOOMR-UHFFFAOYSA-N 0.000 description 2
- 239000004471 Glycine Substances 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- LEVWYRKDKASIDU-IMJSIDKUSA-N L-cystine Chemical compound [O-]C(=O)[C@@H]([NH3+])CSSC[C@H]([NH3+])C([O-])=O LEVWYRKDKASIDU-IMJSIDKUSA-N 0.000 description 2
- 108010006152 Serine racemase Proteins 0.000 description 2
- 102100035717 Serine racemase Human genes 0.000 description 2
- 239000000654 additive Substances 0.000 description 2
- 229940024606 amino acid Drugs 0.000 description 2
- 150000001413 amino acids Chemical class 0.000 description 2
- 238000011437 continuous method Methods 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 2
- 229960003067 cystine Drugs 0.000 description 2
- 238000000354 decomposition reaction Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- VLTRZXGMWDSKGL-UHFFFAOYSA-N perchloric acid Chemical compound OCl(=O)(=O)=O VLTRZXGMWDSKGL-UHFFFAOYSA-N 0.000 description 2
- 238000000746 purification Methods 0.000 description 2
- NWUYHJFMYQTDRP-UHFFFAOYSA-N 1,2-bis(ethenyl)benzene;1-ethenyl-2-ethylbenzene;styrene Chemical compound C=CC1=CC=CC=C1.CCC1=CC=CC=C1C=C.C=CC1=CC=CC=C1C=C NWUYHJFMYQTDRP-UHFFFAOYSA-N 0.000 description 1
- CHZLVSBMXZSPNN-UHFFFAOYSA-N 2,4-dimethylbenzenesulfonic acid Chemical class CC1=CC=C(S(O)(=O)=O)C(C)=C1 CHZLVSBMXZSPNN-UHFFFAOYSA-N 0.000 description 1
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 1
- MTCFGRXMJLQNBG-UWTATZPHSA-N D-Serine Chemical compound OC[C@@H](N)C(O)=O MTCFGRXMJLQNBG-UWTATZPHSA-N 0.000 description 1
- 229930195711 D-Serine Natural products 0.000 description 1
- 108090000790 Enzymes Proteins 0.000 description 1
- 102000004190 Enzymes Human genes 0.000 description 1
- 108090001066 Racemases and epimerases Proteins 0.000 description 1
- 102000004879 Racemases and epimerases Human genes 0.000 description 1
- 239000012345 acetylating agent Substances 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 150000003973 alkyl amines Chemical class 0.000 description 1
- 229910021529 ammonia Inorganic materials 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 238000007664 blowing Methods 0.000 description 1
- 239000001569 carbon dioxide Substances 0.000 description 1
- 229910002092 carbon dioxide Inorganic materials 0.000 description 1
- 239000012295 chemical reaction liquid Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 230000006196 deacetylation Effects 0.000 description 1
- 238000003381 deacetylation reaction Methods 0.000 description 1
- 238000007872 degassing Methods 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 238000001802 infusion Methods 0.000 description 1
- 239000003456 ion exchange resin Substances 0.000 description 1
- 229920003303 ion-exchange polymer Polymers 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- WRDZMZGYHVUYRU-UHFFFAOYSA-N n-[(4-methoxyphenyl)methyl]aniline Chemical compound C1=CC(OC)=CC=C1CNC1=CC=CC=C1 WRDZMZGYHVUYRU-UHFFFAOYSA-N 0.000 description 1
- JCXJVPUVTGWSNB-UHFFFAOYSA-N nitrogen dioxide Inorganic materials O=[N]=O JCXJVPUVTGWSNB-UHFFFAOYSA-N 0.000 description 1
- QJGQUHMNIGDVPM-UHFFFAOYSA-N nitrogen group Chemical group [N] QJGQUHMNIGDVPM-UHFFFAOYSA-N 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000003002 pH adjusting agent Substances 0.000 description 1
- 102000004196 processed proteins & peptides Human genes 0.000 description 1
- 108090000765 processed proteins & peptides Proteins 0.000 description 1
- 238000011403 purification operation Methods 0.000 description 1
- 239000011541 reaction mixture Substances 0.000 description 1
- 125000003607 serino group Chemical group [H]N([H])[C@]([H])(C(=O)[*])C(O[H])([H])[H] 0.000 description 1
- IFGCUJZIWBUILZ-UHFFFAOYSA-N sodium 2-[[2-[[hydroxy-(3,4,5-trihydroxy-6-methyloxan-2-yl)oxyphosphoryl]amino]-4-methylpentanoyl]amino]-3-(1H-indol-3-yl)propanoic acid Chemical compound [Na+].C=1NC2=CC=CC=C2C=1CC(C(O)=O)NC(=O)C(CC(C)C)NP(O)(=O)OC1OC(C)C(O)C(O)C1O IFGCUJZIWBUILZ-UHFFFAOYSA-N 0.000 description 1
- 238000000967 suction filtration Methods 0.000 description 1
- 238000010189 synthetic method Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 238000005979 thermal decomposition reaction Methods 0.000 description 1
- 238000004448 titration Methods 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
Landscapes
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Description
【発明の詳細な説明】 （産業上の利用分野） 本発明は光学活性セリンのラセミ化法に関する。さらに
詳しくは、光学活性セリンの水溶液を比較的低温で加熱
することにより、DL−セリンを製造する方法に関するも
のである。TECHNICAL FIELD The present invention relates to a method for racemizing optically active serine. More specifically, it relates to a method for producing DL-serine by heating an aqueous solution of optically active serine at a relatively low temperature.
セリンは輸液、各種ペプチド等の原料として重要なアミ
ノ酸であるが、飼料用として大幅な需要増が見込まれる
Ｌ−トリプトファンの主原料としても注目されている。
更に、パーマネント、医薬等に用いられるシスティン、
シスチンの原料としても有用なアミノ酸である。Serine is an important amino acid as a raw material for infusions, various peptides and the like, and is also attracting attention as a main raw material for L-tryptophan, which is expected to have a large demand for feed.
Furthermore, cystine used for permanent, medicine, etc.
It is an amino acid that is also useful as a raw material for cystine.
一般的な合成法によって得られるセリンは、DL体である
が通常必要とされるのは光学活性体であり、不要な対掌
体を有効活用するには、これをラセミ化し再分割するこ
とが不可欠となる。Serine obtained by a general synthetic method is a DL form, but an optically active form is usually required. To effectively utilize an undesired enantiomer, it can be racemized and subdivided. Indispensable.
本発明は以上の目的のための工業的に有利なラセミ化法
に関するものである。The present invention relates to an industrially advantageous racemization method for the above purpose.
（従来の技術） 光学活性セリンのラセミ化法に関しては、従来より種々
提案されており、例えば 光学活性セリンを、無水酢酸と接触せしめてラセミ化
する方法（Arch.Biochem.Biophys.83,1（1959））。(Prior Art) Various racemization methods for optically active serine have been proposed in the past. For example, a method for racemizing optically active serine by contacting it with acetic anhydride (Arch.Biochem.Biophys. 83 , 1 ( 1959)).
光学活性セリンをｍ−キシレン−４−スルホン酸塩と
した後、アルキルアミン、アルカノールアミンを使用し
てラセミ化する方法（特公昭51−41616号、特公昭61−8
817号）。A method in which optically active serine is converted to m-xylene-4-sulfonic acid salt and then racemized by using alkylamine and alkanolamine (Japanese Patent Publication Nos. 41416/1976 and 61-8).
No. 817).
光学活性セリンをセリンラセマーゼを用いて酵素的に
ラセミ化する方法（特開昭60−168392号） 光学活性セリンの水溶液を該水溶液の蒸気圧よりも高
い圧力に加圧し、150〜300℃に加熱してラセミ化する方
法（特開昭60−226850号）等がある。Method for enzymatically racemizing optically active serine using serine racemase (JP-A-60-168392) An aqueous solution of optically active serine is pressurized to a pressure higher than the vapor pressure of the aqueous solution and heated to 150 to 300 ° C. And racemization (JP-A-60-226850).
（発明が解決しようとする問題点） 従来の方法により工業化しようとする場合、それぞれ次
のような難点を有する。すなわち の方法ではラセミ化物を脱アセチル化したあと、さら
にアセチル化剤由来物質の除去精製も必要であり、収率
も低い。(Problems to be Solved by the Invention) When attempting to industrialize by a conventional method, each has the following problems. That is, the method requires deacetylation of the racemic compound and then removal and purification of the substance derived from the acetylating agent, resulting in a low yield.
の方法では、高価なｍ−キシレン−４−スルホン酸を
大量に使用し、しかも反応後は脱ｍ−キシレン−４−ス
ルホン酸操作が必要で工程が長い。In the above method, a large amount of expensive m-xylene-4-sulfonic acid is used, and after the reaction, de-m-xylene-4-sulfonic acid operation is required and the process is long.
の方法では、セリンラセマーゼの調整が、容易でな
く、反応混合物からラセマーゼ由来物質を除くための煩
雑な操作が必要であるばかりでなく、反応に長時間を有
する。In the above method, adjustment of serine racemase is not easy, and not only a complicated operation for removing the racemase-derived substance from the reaction mixture is required, but also the reaction takes a long time.
の方法では、反応液中に光学活性セリン以外の物質の
混入が無く、精製が容易で優れた方法ではあるが、高
温、高圧の厳しい条件下の反応であり、工業化する場
合、装置上あるいは運転管理上、望ましい方法とは言い
難い。In this method, substances other than optically active serine are not mixed in the reaction solution, and it is an excellent method because it is easy to purify, but it is a reaction under severe conditions of high temperature and high pressure. In terms of management, it is hard to say that this is the preferred method.
上記のように従来の方法は種々の問題点を有している。As described above, the conventional method has various problems.
ラセミ化反応に当たっては、反応後の精製操作の点から
添加物はできるだけ使用しない方が好ましい。また装置
上、あるいは操作面からは低温、低圧の穏やかな反応条
件が望まれる。In the racemization reaction, it is preferable not to use additives as much as possible from the viewpoint of purification operation after the reaction. In addition, mild reaction conditions of low temperature and low pressure are desired on the apparatus or in terms of operation.
本発明の目的はそのような条件を満たす工業的製法を提
供することを目的とする。It is an object of the present invention to provide an industrial manufacturing method that satisfies such conditions.
（問題点を解決するための手段） 本発明者らは、上記の問題点を解決するため鋭意検討を
重ねた結果、光学活性セリンの水溶液を特定のpHに調整
し、150℃未満に加熱するだけで短時間で、収率よく、
高品質のラセミ化セリンが得られることを見出し本発明
を完成した。(Means for Solving Problems) As a result of intensive studies to solve the above problems, the present inventors have adjusted an aqueous solution of optically active serine to a specific pH and heated it to less than 150 ° C. Just in a short time, good yield,
The present invention has been completed by finding that high-quality racemized serine can be obtained.
即ち、本発明は光学活性セリンの水溶液を、pH3〜９で1
50℃未満の温度に加熱することを特徴とする光学活性セ
リンのラセミ化法である。That is, the present invention provides an aqueous solution of optically active serine at pH 3-9.
It is a racemization method for optically active serine characterized by heating to a temperature of less than 50 ° C.
以下、本発明について詳しく説明する。Hereinafter, the present invention will be described in detail.
本発明の方法で、用いられる原料の光学活性セリンは、
結晶でも、又、例えば無機塩類、グリシンのような不純
物を含んだ精製途中の水溶液であってもよい。更には、
純粋なセリンの状態であっても、又その塩の状態であっ
ても差し支えない。The raw optically active serine used in the method of the present invention is
It may be a crystal or an aqueous solution in the course of purification containing impurities such as inorganic salts and glycine. Furthermore,
It does not matter whether it is in the state of pure serine or in the form of its salt.
反応は水溶液中で行い、仕込時の光学活性セリンの濃度
は、任意に選ぶことができるが、10ないし40重量％とす
るのが好ましい。低濃度では容積効率、エネルギー的に
不利であり、反応時間も長くなる。また高濃度では取扱
が難しくなる。更に該水溶液は、反応前に脱気しておく
ことが好ましい。The reaction is carried out in an aqueous solution, and the concentration of the optically active serine at the time of charging can be arbitrarily selected, but it is preferably 10 to 40% by weight. At low concentrations, it is disadvantageous in volumetric efficiency and energy, and the reaction time becomes long. Also, handling becomes difficult at high concentrations. Further, the aqueous solution is preferably degassed before the reaction.
反応液のpHは３ないし９、好ましくは４ないし７であ
る。pHが３未満の場合は、反応後中和する場合の生成塩
が多く、品質の低下をもたらす。pHが９を越える場合
は、反応液が着色し、更に分解も起こり好ましくない。The pH of the reaction solution is 3 to 9, preferably 4 to 7. When the pH is less than 3, a large amount of salt is formed when the reaction is neutralized, resulting in deterioration of quality. If the pH exceeds 9, the reaction solution is colored and further decomposed, which is not preferable.
pH調整剤は、無機類を用いるが、通常、酸としては硫酸
あるいは塩酸を用い、アルカリとしてはアンモニア、水
酸化ナトリウムを用いる。As the pH adjuster, inorganic substances are used, but usually sulfuric acid or hydrochloric acid is used as the acid, and ammonia or sodium hydroxide is used as the alkali.
反応温度は150℃未満、好ましくは125〜145℃である。1
50℃以上では分解が起こり好ましくない。低温では反応
時間が長くなり好ましくない。The reaction temperature is less than 150 ° C, preferably 125-145 ° C. 1
Decomposition occurs at 50 ° C or higher, which is not preferable. If the temperature is low, the reaction time becomes long, which is not preferable.
更に、該水溶液は、反応前に脱気しておくことが好まし
く、脱気して水溶液中の溶存酸素量を減じることによ
り、セリンのロスが抑えられ、収率が向上する。Further, the aqueous solution is preferably degassed before the reaction, and by degassing to reduce the amount of dissolved oxygen in the aqueous solution, serine loss is suppressed and the yield is improved.
脱気方法は攪拌しながら窒素を吹き込む方法、減圧する
方法等、いかなる方法でもよい。The deaeration method may be any method such as a method of blowing nitrogen while stirring or a method of reducing the pressure.
更にセリンの分解防止のため反応開始前に系内は窒素置
換あるいは炭酸ガス置換をしておくことが望ましい。Furthermore, in order to prevent the decomposition of serine, it is desirable to replace the inside of the system with nitrogen or carbon dioxide before starting the reaction.
反応系は外部より加圧の必要はない。従って、反応圧力
はその温度での水溶液の蒸気圧に、系内不活性ガスの昇
温膨張による圧力増加分を加えた圧力となる。The reaction system does not need to be externally pressurized. Therefore, the reaction pressure is the vapor pressure of the aqueous solution at that temperature plus the pressure increase due to the temperature rise expansion of the inert gas in the system.
反応時間も、反応温度に依存し、高温程反応時間も短く
てよい。例えば130℃でラセミ化反応を行う場合、反応
時間は10時間必要であるが、140℃の場合、５時間で充
分である。The reaction time also depends on the reaction temperature, and the higher the temperature, the shorter the reaction time may be. For example, when the racemization reaction is carried out at 130 ° C., the reaction time is 10 hours, but at 140 ° C., 5 hours is sufficient.
反応の形式は、槽型反応機を用いてのバッチ方式、ある
いは連続方式、もしくは管型反応器による連続方式等い
ずれも使用可能で特に制限はないが熱分解を最小限にす
るという点から、管型連続反応による方法が望ましい。The type of reaction is not particularly limited, but any batch method using a tank reactor, a continuous method, or a continuous method using a tubular reactor can be used, but from the viewpoint of minimizing thermal decomposition, A tubular continuous reaction method is preferred.
（作用及び効果） 従来の種々のラセミ化方法は、光学活性セリンに添加物
等を加える方法や、高温、高圧下の反応等であるが、そ
れによれば反応後の添加物及び添加物由来物質の除去操
作等を必要としたり、装置上、あるいは運転管理上問題
のある方法であった。(Functions and Effects) Various conventional racemization methods include a method of adding an additive or the like to optically active serine, a reaction under high temperature and high pressure, and the like. It is a method that requires a removing operation, etc., and has a problem in terms of equipment or operation management.
本発明による方法は、水溶液のpHを特定範囲に調整し、
150℃未満に加熱することで短時間で収率よく、高品質
のラセミ化セリンを得ることができ、工業的に極めて価
値ある発明である。The method according to the present invention adjusts the pH of the aqueous solution to a specific range,
By heating to less than 150 ° C., high-quality racemized serine can be obtained in a short time with high yield, which is an industrially extremely valuable invention.
実施例 以下、実施例にて本発明を詳しく説明する。Examples Hereinafter, the present invention will be described in detail with reference to Examples.
実施例１ オートクレーブに予め脱気した水300gと結晶Ｌ−セリン
（純度99.0％）100.0gを仕込溶解させた。溶解液のpHは
5.6であった。オートクレーブを密閉し、窒素で充分に
空間部の置換を行った後、攪拌しながら昇温し、内温を
138℃、圧力4.0/cm2Gに維持して５時間反応させた後、
冷却し、反応液をセパラブルフラスコに移し、内溶液が
195.2gになるまで減圧濃縮を行った。Example 1 300 g of degassed water and 100.0 g of crystalline L-serine (purity 99.0%) were charged and dissolved in an autoclave. The pH of the solution is
It was 5.6. After closing the autoclave and sufficiently replacing the space with nitrogen, raise the temperature with stirring to increase the internal temperature.
After reacting at 138 ° C and pressure of 4.0 / cm 2 G for 5 hours,
Cool, transfer the reaction solution to a separable flask, and
Concentration under reduced pressure was performed until the amount reached 195.2 g.
次に、濃縮液を攪拌しながら冷却し、２時間、５℃に保
持して、結晶を析出させ、減圧吸引濾過により結晶を分
別し、５℃の例水70gで洗浄した。得られた湿ケーキを
減圧下70℃で乾燥して、乾燥DL−セリンの白色結晶84.0
gを得た。該セリンの過塩素酸滴定による純度99.4％、
比旋光度＝▲〔α〕20 D▼＝−0.0゜（Ｃ＝10,2NHCl）、
純度換算収率は84.3％であった。Next, the concentrated liquid was cooled with stirring and kept at 5 ° C. for 2 hours to precipitate crystals, and the crystals were separated by suction filtration under reduced pressure, and washed with 70 g of water at 5 ° C. The obtained wet cake was dried under reduced pressure at 70 ° C., and dried DL-serine white crystals 84.0
got g. 99.4% purity of the serine as determined by perchloric acid titration,
Specific optical rotation = ▲ [α] 20 D ▼ = -0.0 ° (C = 10,2NHCl),
The yield in terms of purity was 84.3%.
実施例２ Ｌ−セリン生成酵素を含むグリシン水溶液にホルマリン
を滴下して得られら反応液中のＬ−セリンをイオン交換
樹脂に吸着、次に希アンモニア水で溶離して、Ｌ−セリ
ン水溶液を得た。更に濃縮してＬ−セリン濃度20重量％
に調整した液をラセミ化のテストに供した。Example 2 L-serine in a reaction solution obtained by dropping formalin into an aqueous glycine solution containing an L-serine-forming enzyme was adsorbed on an ion exchange resin and then eluted with dilute aqueous ammonia to give an aqueous L-serine solution. Obtained. Further concentration, L-serine concentration 20% by weight
The solution prepared as above was subjected to a racemization test.
オートクレーブに予め脱気した該反応液20重量％水溶液
400.0gを仕込、98％硫酸でpHを5.7に調整後、系内を密
閉し、窒素で充分に空間部の置換を行った後、攪拌しな
がら昇温し、圧力3.5kg/cm2Gで内温を137℃に維持し
て、５時間反応させた後冷却し、反応液をセパラブルフ
ラスコに移し、内溶液が195.3gになるまで減圧濃縮を行
った。20% by weight aqueous solution of the reaction liquid that had been degassed in an autoclave in advance.
After charging 400.0 g and adjusting the pH to 5.7 with 98% sulfuric acid, the system was sealed and the space was sufficiently replaced with nitrogen, then the temperature was raised with stirring and the pressure was 3.5 kg / cm 2 G. The internal temperature was maintained at 137 ° C., the reaction was carried out for 5 hours and then the reaction solution was cooled, transferred to a separable flask, and concentrated under reduced pressure until the internal solution reached 195.3 g.
その後、実施例１と同様に処理して、乾燥したDL−セリ
ンの白色結晶67.3gを得た。該セリンの純度は、98.8
％、比旋光度＝▲〔α〕20 D▼＝−0.1゜、純度換算収率
は、83.1％であった。Then, the same treatment as in Example 1 was carried out to obtain 67.3 g of dried DL-serine white crystals. The purity of the serine is 98.8
%, Specific optical rotation = ▲ [α] 20 D ▼ = -0.1 °, and the purity conversion yield was 83.1%.
実施例３ 反応温度を130℃とし、反応時間を10時間とした以外は
実施例２と同様にして反応、後処理を行い、DL−セリン
の乾燥白色結晶65.4gを得た。該セリンの純度は99.7
％、比旋光度＝〔α〕20＝＋0.0゜で、純度換算収率は8
1.5％であった。Example 3 The reaction and post-treatment were carried out in the same manner as in Example 2 except that the reaction temperature was 130 ° C. and the reaction time was 10 hours, to obtain 65.4 g of dried white crystals of DL-serine. The purity of the serine is 99.7
%, Specific rotation = [α] 20 = + 0.0 °, and the yield in terms of purity is 8
It was 1.5%.
実施例４ オートクレーブ内の仕込を予め脱気した水80.0gと、結
晶Ｄ−セリン（純度99.8％）20.0gとした他は実施例１
と同様にして、DL−セリンの乾燥白色結晶16.7gを得
た。該セリンの純度は98.8％、比旋光度＝▲〔α〕20 D
▼＝−0.1゜で、純度換算収率は82.7％であった。Example 4 Example 1 except that the charge in the autoclave was 80.0 g of degassed water in advance and 20.0 g of crystalline D-serine (purity 99.8%).
In the same manner as in the above, 16.7 g of dried white crystals of DL-serine were obtained. The purity of the serine is 98.8%, specific optical rotation = ▲ [α] 20 D
▼ = -0.1 °, the yield in terms of purity was 82.7%.
Claims (1)
囲で150℃未満の温度に加熱することを特徴とする光学
活性セリンのラセミ化法。1. A process for racemizing optically active serine, which comprises heating an aqueous solution of optically active serine to a temperature of less than 150 ° C. within a pH range of 3 to 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12260787A JPH0749397B2 (en) | 1987-05-21 | 1987-05-21 | Method for racemization of optically active serine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12260787A JPH0749397B2 (en) | 1987-05-21 | 1987-05-21 | Method for racemization of optically active serine |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63290855A JPS63290855A (en) | 1988-11-28 |
| JPH0749397B2 true JPH0749397B2 (en) | 1995-05-31 |
Family
ID=14840130
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP12260787A Expired - Lifetime JPH0749397B2 (en) | 1987-05-21 | 1987-05-21 | Method for racemization of optically active serine |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0749397B2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5478035B2 (en) * | 2008-07-02 | 2014-04-23 | 三井化学株式会社 | Method for producing DL-serine |
-
1987
- 1987-05-21 JP JP12260787A patent/JPH0749397B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS63290855A (en) | 1988-11-28 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN1197060A (en) | Method for purifying branched chain amino acids | |
| MX2007000524A (en) | Method for the preparation of pregabalin and salts thereof. | |
| KR100399509B1 (en) | Process for purifying valine | |
| KR101899015B1 (en) | Process for the production of l-carnitine tartrate | |
| JPH0749397B2 (en) | Method for racemization of optically active serine | |
| CN105906520B (en) | A kind of recovery method of L-α-methyl-dopa intermediate and application | |
| JPH0623182B2 (en) | Method for separating L-cysteine hydrochloride monohydrate | |
| CN115872883B (en) | A method for preparing high-purity sarcosine | |
| JPS6338B2 (en) | ||
| CN115583891A (en) | Preparation method of high-purity sodium sarcosinate aqueous solution | |
| EP0302624B1 (en) | A method for racemization of optically active serine | |
| JP4001628B2 (en) | Process for producing N-acetyl-D, L-α-aminocarboxylic acid | |
| CN104326901B (en) | Method for recycling and mechanically using L- (+) -tartaric acid in D-ethyl ester production | |
| JPWO1997032841A1 (en) | Method for producing N-trifluoroacetyl-basic amino acids | |
| CN110981801B (en) | Production process for preparing cinchocaine hydrochloride by one-pot method | |
| JPH05178801A (en) | Crystallization method of L-phenylalanine | |
| EP1069109B1 (en) | Process for production of optically active N-protected-N-methyl-phenylalanine derivative | |
| CN113735732A (en) | Refining method of high-purity R- (-) -3-carbamoylmethyl-5-methylhexanoic acid | |
| JP2505487B2 (en) | Racemization of optically active lysine | |
| JP3316917B2 (en) | New phenylalanine salt crystals and their production | |
| GB1587680A (en) | Process for n-acylating amino acids | |
| JP3325433B2 (en) | Method for producing S-phenyl-L-cysteine hydrochloride | |
| JPS63218655A (en) | Optical resolution of n-carbamoylmethionine | |
| JP4031829B2 (en) | Method for racemization of N-acetyl-D (L) -α-aminocarboxylic acid | |
| JPH0325416B2 (en) |