JPS6256491A - Production of high-purity methylcobalamin - Google Patents

Production of high-purity methylcobalamin

Info

Publication number
JPS6256491A
JPS6256491A JP19602085A JP19602085A JPS6256491A JP S6256491 A JPS6256491 A JP S6256491A JP 19602085 A JP19602085 A JP 19602085A JP 19602085 A JP19602085 A JP 19602085A JP S6256491 A JPS6256491 A JP S6256491A
Authority
JP
Japan
Prior art keywords
lower aliphatic
methylcobalamin
water
reaction mixture
adsorbed substance
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.)
Granted
Application number
JP19602085A
Other languages
Japanese (ja)
Other versions
JPH0572920B2 (en
Inventor
Yoshito Kodama
児玉 義人
Yasuo Kubo
久保 安雄
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Eisai Co Ltd
Original Assignee
Eisai Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Eisai Co Ltd filed Critical Eisai Co Ltd
Priority to JP19602085A priority Critical patent/JPS6256491A/en
Publication of JPS6256491A publication Critical patent/JPS6256491A/en
Publication of JPH0572920B2 publication Critical patent/JPH0572920B2/ja
Granted legal-status Critical Current

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  • Nitrogen Condensed Heterocyclic Rings (AREA)
  • Saccharide Compounds (AREA)

Abstract

PURPOSE:To obtain the titled compound useful as a remedy for peripheral neuropathy, etc., by methylating cyanocobalamin, adjusting the pH, bringing the resultant reaction mixture into contant with silica gel and then divinylbenzene/styrene based polymer chromatographic column one after another, eluting the adsorbed substance, concentration the eluate and crystallizing the compound. CONSTITUTION:Cyanocobalamin is methylated by a conventional method, e.g. reduction and methylation, etc., to give a reaction mixture consisting essentially of methylcobalamin. The resultant reaction mixture is then adjusted to 2.5-7.0 pH, passed through a silica gel column and adsorbed. A lower aliphatic alcohol-water mixture or aliphatic ketone-water mixture is discharged to the adsorbed substance and a lower aliphatic alcohol-water mixture is discharged to the adsorbed substance to distill away the adsorbed substance. The resultant distillate is then brought into contact with a divinylbenzene/styrene based copolymer chromatographic column. In the process, the concentration of the lower aliphatic alcohol-water, etc., is increased from the lower to the higher concentration stepwise to elute the adsorbed substance. The adsorbed substance is finally desorbed with a lower aliphatic ketone-water mixture and the distillate is then concentrated. A lower aliphatic ketone is then added thereto to crystallize the aimed compound.

Description

【発明の詳細な説明】 産業上の利用分野 本発明は、医薬として実用に供しつる高純度のメチルコ
バラミンの製造方法に関する。
DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for producing highly pure methylcobalamin that can be practically used as a medicine.

従来の技術 メチルコバラミンは、血液および髄液存在型の補酵素型
BI2として、神経細胞などの組織移行性に優れている
。生化学的にはメチル基転移反応に関与し、核酸・蛋白
・脂質代謝においてB1□同族体の中で最も優れた生体
内活性を示す。臨床的には。
BACKGROUND OF THE INVENTION Methylcobalamin, as a coenzyme type BI2 present in blood and cerebrospinal fluid, has excellent migration properties into tissues such as nerve cells. Biochemically, it is involved in methyl group transfer reactions, and exhibits the highest in vivo activity among B1□ homologs in nucleic acid, protein, and lipid metabolism. Clinically.

巨歩芽球性貧血に有効であるのみならず、糖尿病性神経
障害、多発性神経炎などの末梢性神経障害治療剤として
有効である。
It is effective not only for macroblastic anemia but also as a therapeutic agent for peripheral neuropathies such as diabetic neuropathy and polyneuritis.

メチルコバラミンの製法についての種々の方法が知られ
ているが9代表的な方法としては例えば出発原料として
シアノコバラミンを使用する方法がある(特公昭45−
38059)。
Various methods are known for the production of methylcobalamin.9 A typical method is, for example, a method using cyanocobalamin as a starting material (Japanese Patent Publication No. 1973-
38059).

発明が解決しようとする問題点 この合成法によって得られたメチルコバラミン含有溶液
中には、微量のシアノコバラミン、ヒドロキソコバラミ
ン、更に黄色物質、塩類などが含有されている。したが
って、いかにしてこれらのメチコバール以外の挾雑成分
を除き、高純度のメチルコバラミンを得るかが問題であ
る。
Problems to be Solved by the Invention The methylcobalamin-containing solution obtained by this synthesis method contains trace amounts of cyanocobalamin, hydroxocobalamin, yellow substances, salts, and the like. Therefore, the problem is how to remove these interfering components other than methicobal and obtain highly pure methylcobalamin.

これらの挾雑成分を除去する方法としては、これらの物
質は塩類を除いてその性質が近似しているため、吸着性
の差を利用した方法2例えば、イオン交換樹脂クロマト
グラフィーによる方法および水−ア七トン結晶化法など
がすでに知られている。
As methods for removing these interfering components, since these substances have similar properties except for salts, there are two methods that take advantage of the difference in adsorption properties, such as a method using ion exchange resin chromatography and a water-based method. A seven-ton crystallization method is already known.

しかしながら、これらの方法は1次のような欠点を有す
る。すなわち、イ木ン交換樹脂受側クロマトグラフィー
による方法は、イオン交換樹脂が高価なため、再利用す
るための別途設備を要するという欠点を有し、また水−
ア七トン結晶化法では化学的性質が近似しているため2
 メチルコバラミンの分離精製は困難であるという欠点
を有している。
However, these methods have the following drawbacks. That is, the method using ion-exchange resin receiving side chromatography has the drawback that the ion-exchange resin is expensive and requires separate equipment for reuse.
Since the chemical properties are similar in the a7ton crystallization method, 2
Methylcobalamin has the disadvantage that it is difficult to separate and purify it.

問題点を解決するための手段 そこで2本発明者等は、これらの欠点を有しない高純度
メチルコバラミンを得るため、長年にわたって研究を重
ねてきたが1次の手段により解決できることを見い出し
2本発明を完成した。すなわち。
Means for Solving the ProblemsThe inventors of the present invention have conducted research for many years in order to obtain high-purity methylcobalamin that does not have these drawbacks, and have found that the problem can be solved by the following means.2The present invention has been made. completed. Namely.

シアノコバラミンを常法によりメチル化して。Methylate cyanocobalamin using a conventional method.

メチルコバラミンを主成分とする反応混合物を得。A reaction mixture containing methylcobalamin as the main component was obtained.

この反応混合物を出発物質としてこれを精製し。This reaction mixture was used as a starting material to purify it.

高純度のメチルコバラミンを得る工程において。In the process of obtaining high purity methylcobalamin.

次の5つの工程を結合することを特徴とする高純度のメ
チルコバラミンの製造法 ■ 反応混合液のpHを約2.5〜7.0に調整する工
程。
A method for producing highly pure methylcobalamin characterized by combining the following five steps. (1) A step of adjusting the pH of the reaction mixture to about 2.5 to 7.0.

■ シリカゲルに接触させ、該吸着物に低級脂肪族アル
コール−水または低級脂肪族ケトン−水を流出せしめる
工程。
(2) A step of bringing into contact with silica gel and causing lower aliphatic alcohol-water or lower aliphatic ketone-water to flow out into the adsorbed material.

(■ 次いで該吸着物に、低級脂肪族アルコール−水を
流出せしめ、吸着物を留出する工程。
(2) Next, lower aliphatic alcohol-water is allowed to flow out into the adsorbent, and the adsorbate is distilled out.

■ 該留出液をジビニルベンゼン/スチレン系共重合体
樹脂クロマトグラフィーと接触させ、その際低級脂肪族
アルコール−水または低級脂肪族ケトン−水を低濃度か
ら段階的に濃度をあげて溶出せしめる工程。
(2) A step in which the distillate is brought into contact with divinylbenzene/styrene copolymer resin chromatography, and lower aliphatic alcohol-water or lower aliphatic ketone-water is eluted from a low concentration by increasing the concentration stepwise. .

■ 吸着部を低級脂肪族ケトン−水を流出して吸着物を
脱着せしめ、該留出液を濃縮し、低級脂肪族ケトンを加
えて結晶化させ、結晶部より高純度のメチルコバラミン
を得る工程 出発物質として用いるメチルコバラミンを主成分とする
反応混合物とは、シアノコバラミンを常法によりメチル
化して得られるが、具体的に代表的な方法を述べれ6ば
9例えば特公昭45−38059実施例3に記載されて
いる方法であり2本法によれば、主成分としてのメチル
コバラミンのほか。
■ A step of draining the lower aliphatic ketone-water from the adsorption section to desorb the adsorbate, concentrating the distillate, adding lower aliphatic ketone to crystallize it, and obtaining highly purified methylcobalamin from the crystallization section. The reaction mixture containing methylcobalamin as a main component used as a starting material is obtained by methylating cyanocobalamin by a conventional method. According to the method described and two methods, in addition to methylcobalamin as the main component.

不純物トしてシアノコバラミン、ヒドロキシコバラミ:
/、 Me−Conp、 NaC1!などの塩類などを
含有するものである。
Impurities such as cyanocobalamin and hydroxycobalamin:
/, Me-Comp, NaC1! It contains salts such as.

本発明は、これを出発物質として不純物を除去し、高純
度のメチルコバラミンを得る方法であるが、上記の工程
を更に詳細に述べれば次のとおりである。
The present invention is a method for obtaining highly pure methylcobalamin by using this as a starting material and removing impurities. The above steps will be described in more detail as follows.

■の工程 反応混合物のpHを約2.5〜7.0に調整する工程で
あるが2通常は希塩酸水溶液、好ましくは0.03N以
下の希塩酸を用いておこなう。pHは5前後が最も好ま
しい。この範囲のpHに調整することによって吸着量の
増加と溶出分難に著しく効果がある。pH7,0を超え
た場合は未分離となり不利である。
Step (2) This step is to adjust the pH of the reaction mixture to about 2.5 to 7.0.2 It is usually carried out using a dilute aqueous hydrochloric acid solution, preferably dilute hydrochloric acid of 0.03N or less. The pH is most preferably around 5. Adjusting the pH to within this range has a significant effect on increasing the amount of adsorption and reducing the difficulty of elution. If the pH exceeds 7.0, it will not be separated, which is disadvantageous.

(のの工程 このメチル化反応液を、シリカゲルに接触さぜる工程で
ある。シリカゲルとしては例えばシリカゲル−40(メ
ルク社製)などを用いる。シリカゲル−40は、比表面
積が650 m / 、!i’で他のシリカ1ゲルに比
し大きく吸着に有利である。
(This step is a step in which the methylation reaction solution is brought into contact with silica gel. For example, silica gel-40 (manufactured by Merck & Co., Ltd.) is used as the silica gel. Silica gel-40 has a specific surface area of 650 m / ! i' is much more advantageous for adsorption than other silica 1 gels.

溶出は、低級脂肪族アルコール−水または低級脂肪族ケ
トン−水、好ましくはメタノールを用い。
For elution, use lower aliphatic alcohol-water or lower aliphatic ketone-water, preferably methanol.

sv O,7でおこなうことが好結果を与える。メタノ
ールは約596のアセトンが好ましい。
Performing with sv O,7 gives good results. Methanol is preferably about 596 acetone.

この操作により、目的物質は吸着部にあり、塩化ナトリ
ウム、ヒドロキシコバラミンなどが非吸着部分として除
かれる。
By this operation, the target substance is present in the adsorption part, and sodium chloride, hydroxycobalamin, etc. are removed as non-adsorbed parts.

■の工程 目的物質であるメチルコバラミンを含む吸着物に、更に
低級脂肪族アルコール類−水を流出せしめ、吸着物を留
出する工程である。この際svは0.5〜1.0の範囲
でおこなうことが好ましい。
Step (2) This is a step in which lower aliphatic alcohol-water is further allowed to flow out into the adsorbate containing methylcobalamin, which is the target substance, and the adsorbate is distilled out. At this time, it is preferable that sv is in the range of 0.5 to 1.0.

低級脂肪族アルコール類とは、メ、タノール、エタノー
ル、プロパツール、ブタノールなどがあげられるが、メ
タノールが最も好ましい。メタノールの濃度は1596
前後が好ましい結果を与える。
Examples of lower aliphatic alcohols include methanol, ethanol, propatool, butanol, and the like, with methanol being the most preferred. The concentration of methanol is 1596
Before and after gives favorable results.

この工程により目的物質であるメチルコバラミンは非吸
着部分にあり、吸着されるのは黄色不純物である。非吸
着部分には、メチルコバラミンのほか、シアノコバラミ
ンが存在するものと考えられる。
Through this process, the target substance, methylcobalamin, is present in the non-adsorbed portion, and what is adsorbed is the yellow impurity. It is thought that cyanocobalamin is present in the non-adsorbed portion in addition to methylcobalamin.

■の工程 該留出液を、ジビニルベンゼン/スチレン系共重合体樹
脂に接触させる工程である。
Step (2) This is a step in which the distillate is brought into contact with a divinylbenzene/styrene copolymer resin.

ジビニルベンゼン/スチレン系共重合体はポリスチレン
系のもので、構造的には下記の構造(I)を有している
The divinylbenzene/styrene copolymer is polystyrene-based and structurally has the following structure (I).

具体例をあげれば9例えばダイヤイオンHP −20ま
たはダイヤイオンHP −40などをあげることができ
る。
Specific examples include Diaion HP-20 and Diaion HP-40.

溶出は、低級脂肪族アルコール−水、または低級脂肪族
ケトン−水でおこなうが、最も好ましいのは、10%ア
セトン水溶液でSVは1.0程度である。
Elution is carried out using lower aliphatic alcohol-water or lower aliphatic ketone-water, but most preferably a 10% acetone aqueous solution with an SV of about 1.0.

この操作により、非吸着部分にはシアノコバラミンが、
吸着部分には、目的物であるメチルコバラミンが存在す
る。
Through this operation, cyanocobalamin is present in the non-adsorbed area.
The target substance, methylcobalamin, is present in the adsorption part.

■の工程 吸着部から目的物質であるメチルコバラミンを得る方法
である。
Step (2) This is a method for obtaining the target substance methylcobalamin from the adsorption section.

具体的には、低級脂肪族ケトン、好ましくは20%アセ
トン水溶液を、上記カラムにs v 1.0で流し。
Specifically, a lower aliphatic ketone, preferably a 20% acetone aqueous solution, is passed through the above column at s v 1.0.

目的物を脱着せしめたのち、更に低級脂肪族ケトン、好
ましくはアセトンで結晶化し、常法により目的物である
メチルコバラミンを得ることができる。
After the target product is desorbed, it is further crystallized with a lower aliphatic ketone, preferably acetone, and the target product, methylcobalamin, can be obtained by a conventional method.

本発明のメリットを要約すると次のとおりである。The advantages of the present invention are summarized as follows.

(1)高純度拳高収帛のメチルコバラミンを得る工業的
な方法である。
(1) It is an industrial method for obtaining highly purified methylcobalamin in high yield.

(2)本性では、シリカゲルクロマトおよびジビニルベ
ンゼン/スチレン系共重合体樹脂クロマトの再精製工程
を食塩および低級アルコールおよび低級ケトンの水溶液
で、同一カラム内溶出除去をおこなうため、大幅な時間
短縮と、精製設備が不要である。
(2) In the original process, the repurification process of silica gel chromatography and divinylbenzene/styrene copolymer resin chromatography is performed by elution and removal within the same column using an aqueous solution of common salt, lower alcohol, and lower ketone, which significantly shortens the time. No purification equipment is required.

次に2本発明の代表的な実施例を掲げるが2本発明がこ
れらのみに限定されることがないことはいうまでもない
Next, two representative examples of the present invention will be listed, but it goes without saying that the present invention is not limited to these only.

実施例1 シアノコバラミンからメチルコバラミンを製造する方法
(特公昭45−38059)にしたがい、還元・メチル
化反応(シアノコバラミン8.0.9)ヲオこない2反
応溶液から残余のヨードメチルを濃縮留去し、 959
6メチルコバラミン含有メタノール−水溶液600 c
cを得た。
Example 1 According to the method for producing methylcobalamin from cyanocobalamin (Japanese Patent Publication No. 45-38059), the reduction and methylation reaction (cyanocobalamin 8.0.9) was carried out. 2 The remaining iodomethyl was concentrated and distilled off from the reaction solution.
6 Methylcobalamin-containing methanol-aqueous solution 600 c
I got c.

溶液を希塩酸水溶液(0,03N以下)にて、  pH
5,0に調整した後、シリカゲ/l/ (Kiesel
gel−40メルり社製)500ccが充填されたカラ
ムにs v Q、5の流速で吸着させる。次いで、5%
メタノール水溶液500 ccを5VO97にて溶出し
、ヒドロキソコバラミン、食塩および金属錯体塩(可溶
化物)の除去をおこなう。次いで、15%メタノール水
溶液1500ccをs v 0.5で流し、 9996
メチルコバラミン、微量のシアノコバラミンを含有する
溶液1000 ml、を溶出した。この溶液をジビニル
ベンゼン・スチレン共重合体樹脂(ダイヤイオンHP 
−20) 1000ccが充填されているカラムに導き
、svO,5で吸着せしめ。
Adjust the solution to pH with dilute aqueous hydrochloric acid solution (0.03N or less).
After adjusting to 5,0, silicage/l/ (Kiesel
It is adsorbed onto a column packed with 500 cc of gel-40 (manufactured by Merli) at a flow rate of s v Q, 5. Then 5%
Elute 500 cc of methanol aqueous solution with 5VO97 to remove hydroxocobalamin, common salt, and metal complex salt (solubilized material). Next, 1500 cc of 15% methanol aqueous solution was poured at s v 0.5, and 9996
1000 ml of a solution containing methylcobalamin and trace amounts of cyanocobalamin was eluted. Add this solution to divinylbenzene/styrene copolymer resin (Diaion HP)
-20) Guided to a column packed with 1000cc and adsorbed at svO,5.

続いて1096ア七トン水溶液4000 ccをs v
 1.0で流し、シアノコバラミンを除去し、続いて2
0%ア七トン水溶液1500ccをSvl、0で流し、
メチルコバラミン1000 ccを溶出した。これを6
0℃以下で減圧。
Subsequently, sv
Run at 1.0 to remove cyanocobalamin, followed by 2
Pour 1500 cc of 0% aqueous solution at Svl, 0,
1000 cc of methylcobalamin was eluted. This is 6
Depressurize below 0℃.

濃縮し、 100cc水溶液とした。これにアセトン1
00 cc加えて、40℃に溶解後、アセトン800C
Cを徐々に滴下、結晶化をおこない、メチルコバラミン
q、4pc収率9245%)を得た。結晶はHPLC法
で含量測定の結果メチルコバラミン99.9%であり。
It was concentrated to make 100 cc of an aqueous solution. Add 1 part of acetone to this
Add 00 cc and dissolve at 40℃, then add acetone 800C
C was gradually added dropwise to effect crystallization to obtain methylcobalamin q (4 pc, yield 9245%). The content of the crystals was determined by HPLC and was found to be 99.9% methylcobalamin.

シアノコバラミンは検出されなかった。Cyanocobalamin was not detected.

Claims (1)

【特許請求の範囲】[Claims] (1)シアノコバラミンを常法によりメチル化して、メ
チルコバラミンを主成分とする反応混合物を得、この反
応混合物を出発物質としてこれを精製し、高純度のメチ
ルコバラミンを得る工程において、次の5つの工程を結
合することを特徴とする高純度のメチルコバラミンの製
造法 [1]反応混合液のpHを約2.5〜7.0に調整する
工程、 [2]シリカゲルに接触させ、該吸着物に低級脂肪族ア
ルコール−水または低級脂肪族ケトン−水を流出せしめ
る工程、 [3]次いで該吸着物に、低級脂肪族アルコール−水を
流出せしめ、吸着物を留出する工程、 [4]該留出液をジビニルベンゼン/スチレン系共重合
体樹脂クロマトグラフィーと接触させ、その際、低級脂
肪族アルコール−水または低級脂肪族ケトン−水を低濃
度から段階的に濃度をあげて溶出せしめる工程、 [5]吸着部を、低級脂肪族ケトン−水を流出して吸着
物を脱着せしめ、該留出液を濃縮し、低級脂肪族ケトン
を加えて結晶化させ、結晶部より高純度のメチルコバラ
ミンを得る工程
(1) Cyanocobalamin is methylated by a conventional method to obtain a reaction mixture containing methylcobalamin as a main component, and this reaction mixture is used as a starting material to purify it to obtain highly pure methylcobalamin. A method for producing high-purity methylcobalamin characterized by combining the following steps: [1] Adjusting the pH of the reaction mixture to about 2.5 to 7.0; [2] Bringing the reaction mixture into contact with silica gel to remove the adsorbent. a step of causing lower aliphatic alcohol-water or lower aliphatic ketone-water to flow out, [3] a step of then allowing lower aliphatic alcohol-water to flow out to the adsorbent, and distilling the adsorbent, [4] a step of distilling the adsorbent. Contacting the distillate with divinylbenzene/styrene copolymer resin chromatography, at which time lower aliphatic alcohol-water or lower aliphatic ketone-water is eluted from a low concentration by increasing the concentration stepwise; [5] The lower aliphatic ketone-water is drained from the adsorption part to desorb the adsorbed matter, the distillate is concentrated, and the lower aliphatic ketone is added to crystallize it, and highly purified methylcobalamin is extracted from the crystal part. process of obtaining
JP19602085A 1985-09-06 1985-09-06 Production of high-purity methylcobalamin Granted JPS6256491A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP19602085A JPS6256491A (en) 1985-09-06 1985-09-06 Production of high-purity methylcobalamin

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP19602085A JPS6256491A (en) 1985-09-06 1985-09-06 Production of high-purity methylcobalamin

Publications (2)

Publication Number Publication Date
JPS6256491A true JPS6256491A (en) 1987-03-12
JPH0572920B2 JPH0572920B2 (en) 1993-10-13

Family

ID=16350883

Family Applications (1)

Application Number Title Priority Date Filing Date
JP19602085A Granted JPS6256491A (en) 1985-09-06 1985-09-06 Production of high-purity methylcobalamin

Country Status (1)

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CN105801647A (en) * 2016-04-17 2016-07-27 张春燕 Mecobalamine compound, preparation containing mecobalamine compound and preparation method

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105801647A (en) * 2016-04-17 2016-07-27 张春燕 Mecobalamine compound, preparation containing mecobalamine compound and preparation method
CN105801647B (en) * 2016-04-17 2018-08-17 张春燕 Mecobalamin compound and contain its preparation and preparation method

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