DE1470022C3 - Process for the production of the inner ether of pyridoxine - Google Patents

Process for the production of the inner ether of pyridoxine

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Publication number
DE1470022C3
DE1470022C3 DE1962M0052802 DEM0052802A DE1470022C3 DE 1470022 C3 DE1470022 C3 DE 1470022C3 DE 1962M0052802 DE1962M0052802 DE 1962M0052802 DE M0052802 A DEM0052802 A DE M0052802A DE 1470022 C3 DE1470022 C3 DE 1470022C3
Authority
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Germany
Prior art keywords
pyridoxine
production
inner ether
methyl
mixture
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
Application number
DE1962M0052802
Other languages
German (de)
Other versions
DE1470022B2 (en
DE1470022A1 (en
Inventor
Raymond Armond Westfield Firestone
Elbert Everett Elizabeth Harris
Karl Westfield Pfister
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.)
Merck and Co Inc
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Merck and Co Inc
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 Merck and Co Inc filed Critical Merck and Co Inc
Publication of DE1470022A1 publication Critical patent/DE1470022A1/en
Publication of DE1470022B2 publication Critical patent/DE1470022B2/en
Application granted granted Critical
Publication of DE1470022C3 publication Critical patent/DE1470022C3/en
Expired legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D213/00—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members
    • C07D213/02—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members
    • C07D213/04—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members having no bond between the ring nitrogen atom and a non-ring member or having only hydrogen or carbon atoms directly attached to the ring nitrogen atom
    • C07D213/60—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members having no bond between the ring nitrogen atom and a non-ring member or having only hydrogen or carbon atoms directly attached to the ring nitrogen atom with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
    • C07D213/78—Carbon atoms having three bonds to hetero atoms, with at the most one bond to halogen, e.g. ester or nitrile radicals
    • C07D213/79—Acids; Esters
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K31/00—Medicinal preparations containing organic active ingredients
    • A61K31/33—Heterocyclic compounds
    • A61K31/395—Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins
    • A61K31/435—Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins having six-membered rings with one nitrogen as the only ring hetero atom
    • A61K31/44—Non condensed pyridines; Hydrogenated derivatives thereof
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D213/00—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members
    • C07D213/02—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members
    • C07D213/04—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members having no bond between the ring nitrogen atom and a non-ring member or having only hydrogen or carbon atoms directly attached to the ring nitrogen atom
    • C07D213/60—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members having no bond between the ring nitrogen atom and a non-ring member or having only hydrogen or carbon atoms directly attached to the ring nitrogen atom with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
    • C07D213/62—Oxygen or sulfur atoms
    • C07D213/63—One oxygen atom
    • C07D213/65—One oxygen atom attached in position 3 or 5
    • C07D213/66—One oxygen atom attached in position 3 or 5 having in position 3 an oxygen atom and in each of the positions 4 and 5 a carbon atom bound to an oxygen, sulphur, or nitrogen atom, e.g. pyridoxal
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D213/00—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members
    • C07D213/02—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members
    • C07D213/04—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members having no bond between the ring nitrogen atom and a non-ring member or having only hydrogen or carbon atoms directly attached to the ring nitrogen atom
    • C07D213/60—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members having no bond between the ring nitrogen atom and a non-ring member or having only hydrogen or carbon atoms directly attached to the ring nitrogen atom with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
    • C07D213/62—Oxygen or sulfur atoms
    • C07D213/63—One oxygen atom
    • C07D213/65—One oxygen atom attached in position 3 or 5
    • C07D213/66—One oxygen atom attached in position 3 or 5 having in position 3 an oxygen atom and in each of the positions 4 and 5 a carbon atom bound to an oxygen, sulphur, or nitrogen atom, e.g. pyridoxal
    • C07D213/67—2-Methyl-3-hydroxy-4,5-bis(hydroxy-methyl)pyridine, i.e. pyridoxine
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D491/00—Heterocyclic compounds containing in the condensed ring system both one or more rings having oxygen atoms as the only ring hetero atoms and one or more rings having nitrogen atoms as the only ring hetero atoms, not provided for by groups C07D451/00 - C07D459/00, C07D463/00, C07D477/00 or C07D489/00
    • C07D491/02—Heterocyclic compounds containing in the condensed ring system both one or more rings having oxygen atoms as the only ring hetero atoms and one or more rings having nitrogen atoms as the only ring hetero atoms, not provided for by groups C07D451/00 - C07D459/00, C07D463/00, C07D477/00 or C07D489/00 in which the condensed system contains two hetero rings
    • C07D491/04—Ortho-condensed systems

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Pharmacology & Pharmacy (AREA)
  • Epidemiology (AREA)
  • Medicinal Chemistry (AREA)
  • Animal Behavior & Ethology (AREA)
  • General Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Pyridine Compounds (AREA)
  • Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
  • Plural Heterocyclic Compounds (AREA)
  • Heterocyclic Carbon Compounds Containing A Hetero Ring Having Nitrogen And Oxygen As The Only Ring Hetero Atoms (AREA)

Description

in der R einen Alkylrest mit 1 bis 10 Kohlenstoffatomen bedeutet, mit 2,5-Dihydrofuran bei einer Temperatur von 150 bis 200° C umsetzt.in which R is an alkyl radical having 1 to 10 carbon atoms, with 2,5-dihydrofuran in one Reacts temperature of 150 to 200 ° C.

Der Gegenstand der Erfindung ist im Patentanspruch definiert.The subject matter of the invention is defined in the claim.

Die bisher für die Herstellung von Pyridoxin zur Verfugung stehenden Methoden umfassen vielstufige Verfahren, die in technischem Maßstab schwierig durchzuführen sind.The methods currently available for the production of pyridoxine include multi-step methods Processes that are difficult to carry out on an industrial scale.

Aus Khim. Nauka i. Prom., Bd. 2 (1957), S. 666 und 667, zitiert in Chem. Abstr., Bd. 52 (1958), Spalte 6345, 2. Absatz, sowie aus Izvest Akad. Nauk S.S.S.R., Otdel. Khim. Nauk 1959, S. 484—490, zitiert in Chem. Abstr., Bd. 53 (1959), Spalte 21 940, 2. Absatz, ist die Kondensation von alkyl- und tetramethylensubstituierten Oxazolen mit Maleinsäure und Maleinsäureanhydrid zu der entsprechend substituierten Cinchomeronsäure bekannt.From Khim. Nauka i. Prom., Vol. 2 (1957), pp. 666 and 667, cited in Chem. Abstr., Vol. 52 (1958), column 6345, 2. Paragraph, as well as from Izvest Akad. Nauk S.S.S.R., Otdel. Khim. Nauk 1959, pp. 484-490, cited in Chem. Abstr., Vol. 53 (1959), column 21 940, 2nd paragraph, is the condensation of alkyl- and tetramethylene-substituted Oxazoles with maleic acid and maleic anhydride to form the correspondingly substituted cinchomeronic acid known.

Das erfindungsgemäße Verfahren unterscheidet sich von den aus der russichen Literatur bekannten Verfahren dadurch, daß erfindungsgemäß durch Umsetzung eines 4-Methyl-5-alkoxyoxazols der allgemeinen FormelThe method according to the invention differs from that known from Russian literature Process in that according to the invention by reacting a 4-methyl-5-alkoxyoxazole of the general formula

N-N-

IlIl

H-CH-C

-C-CH,
C-OR-C-CH,
C-OR

in der R einen Alkylrest mit 1 bis 10 Kohlenstoffatomen bedeutet, mit 2,5-Dihydrofuran bei einer Temperatur von 150 bis 200° C der innere Äther des Pyridoxins hergestellt wird.in which R is an alkyl radical with 1 to 10 carbon atoms means with 2,5-dihydrofuran at a temperature of 150 to 200 ° C the inner ether of pyridoxine will be produced.

Aus der so hergestellten Verbindung läßt sich günstig Pyridoxin gewinnen.Pyridoxine can be obtained inexpensively from the compound produced in this way.

Der Rest R kann z. B. der Methyl-, Äthyl-, Isopropyl-, Butyl-, Isobutyl-, Amyl- oder Octylrest sein.The remainder R can, for. B. the methyl, ethyl, isopropyl, Butyl, isobutyl, amyl or octyl radical.

Das Verfahren kann in Gegenwart eines geeigneten Lösungsmittels für die Reaktionskomponenten, wie Methanol oder Benzol, durchgeführt werden.The process can be carried out in the presence of a suitable solvent for the reaction components, such as Methanol or benzene.

Die Herstellung der als Ausgangsverbindungen dienenden 4-Methyl-5-niedrigmol.-alkoxyoxazole wird an der Herstellung von 4-Methyl-5-äthoxyoxazol erläutert.The preparation of the 4-methyl-5-low molar alkoxyoxazoles used as starting compounds is explained on the production of 4-methyl-5-ethoxyoxazole.

ίο Zu 35 g a-Alaninäthylester-hydrochlorid werden 10 g Formamid zugegeben. Das erhaltene Gemisch wird langsam innerhalb von 30—45 Minuten auf 105°C erhitzt Nach 10 Minuten Erhitzen bei 105° C werden 75 ml Toluol zugegeben. Nach 1 Stunde Stehenlassen wird das Gemisch dann 6 Stunden unter Rückfluß erhitzt. Nach Abkühlen wird das gebildete Ammoniumchlorid entfernt und die erhaltene Lösung zur Entfernung des Lösungsmittels eingedampft. Der N-Formyl-«-alaninäthylester wird durch Destillation bei 100° C bei 0,9 mm Druck erhalten.ίο 10 g are added to 35 g of a-alanine ethyl ester hydrochloride Formamide added. The resulting mixture is slowly raised to 105 ° C in 30-45 minutes heated After 10 minutes of heating at 105 ° C., 75 ml of toluene are added. Let stand after 1 hour the mixture is then refluxed for 6 hours. After cooling, the ammonium chloride formed is removed and the resulting solution evaporated to remove the solvent. Of the N-formyl - «- alanine ethyl ester is obtained by distillation at 100 ° C. at 0.9 mm pressure.

Zu einem Gemisch von 25 ml alkoholfreiem Chloroform und 11,36 g P2O5 wird innerhalb von 20 Minuten eine Lösung von 5,81 g des Esters in 15 ml alkoholfreiem Chloroform bei etwa 3O0C zugegeben. Das erhaltene Reaktionsgemisch wird 1 Stunde Rückfluß erhitzt und abgekühlt, das Lösungsmittel wird abdekantiert. Die zurückbleibende harte Masse wird zerkleinert und langsam mit einer Lösung von 27 g Kaliumhydroxid in 27 ml Wasser und 34 ml Methanol versetzt, wobei die Temperatur bei 10—20°C gehalten wird. Die erhaltene Lösung wird 1 Stunde unter Rückfluß erhitzt, abgekühlt und zehnmal mit je 15 ml Methylenchlorid extrahiert. Das 4-Methyl-5-äthoxyoxazol wird nach Entfernen des Lösungsmittels durch Destillation bei 75—80°C bei 10 mm Druck gewonnen.To a mixture of 25 ml of alcohol-free chloroform, and 11.36 g of P2O5 and a solution of 5.81 g of the ester in 15 ml of alcohol-free chloroform at about 3O 0 C was added over 20 minutes. The reaction mixture obtained is refluxed for 1 hour and cooled, and the solvent is decanted off. The remaining hard mass is crushed and slowly mixed with a solution of 27 g of potassium hydroxide in 27 ml of water and 34 ml of methanol, the temperature being kept at 10-20 ° C. The resulting solution is refluxed for 1 hour, cooled and extracted ten times with 15 ml of methylene chloride each time. The 4-methyl-5-ethoxyoxazole is obtained after removal of the solvent by distillation at 75-80 ° C under 10 mm pressure.

Beispielexample

Folgende Bestandteile werden in den angegebenen Mengen miteinander vermischt:
40 The following ingredients are mixed together in the specified amounts:
40

1,01 g 4-Methyl-5-äthoxyoxazol
11,21 g 2,5-Dihydrofuran
0,13 g Trifluoressigsäure1.01 g of 4-methyl-5-ethoxyoxazole
11.21 grams of 2,5-dihydrofuran
0.13 g trifluoroacetic acid

Das Gemisch wird 3 Std. lang in einer Bombe auf 175° C erhitzt. Die Bombe wird dann abgekühlt und über Nacht bei Raumtemperatur stehengelassen. Nach dem öffnen wird der Inhalt filtriert. Die so erhaltenen Kristalle des rohen inneren Ähters des Pyrido>ains werden mit 2 ml frischem Dihydrofuran gewaschen und an der Luft getrocknet. Man erhält 1,49 g Produkt. Die UV-Analyse in einer Phosphatpufferlösung (pH-Wert 7) ergibt folgende Werte:The mixture is heated in a bomb at 175 ° C. for 3 hours. The bomb is then cooled and put over Left to stand at room temperature overnight. After opening, the contents are filtered. The so obtained Crystals of the crude inner ether of pyrido> aine are washed with 2 ml of fresh dihydrofuran and air dried. 1.49 g of product are obtained. UV analysis in a phosphate buffer solution (pH 7) results in the following values:

Analysenreines Produkt: kmax = 309 πιμ, ElI= 589;
gefunden: kmax = 309 πιμ, Ε,'ϋ'= 554.Analytically pure product: k max = 309 πιμ, ElI = 589;
found: k max = 309 πιμ, Ε, 'ϋ' = 554.

Die Reinheit des inneren Äthers des Pyridoxins beträgt demnach 94,1 %.The purity of the inner ether of the pyridoxine is therefore 94.1%.

Durch Umkristallisieren aus 13 ml 1 n-äthanolischem Chlorwasserstoff je g des rohen Produkts erhält man Kristalle des reinen Hydrochloride, die bei 239—240° C schmelzen und mit einer authentischen Probe völlig übereinstimmen.Recrystallization from 13 ml of 1N-ethanolic hydrogen chloride per g of the crude product is obtained Crystals of pure hydrochloride, which are at 239-240 ° C melt and completely match an authentic sample.

Claims (1)

Patentanspruch:Claim: Verfahren zur Herstellung des inneren Äthers des Pyridoxins der FormelProcess for the preparation of the inner ether of pyridoxine of the formula dadurch gekennzeichnet, daß man ein 4-Methyl-5-alkoxyoxazol der allgemeinen Formelcharacterized in that a 4-methyl-5-alkoxyoxazole of the general formula N-H-C N-H-C -C-CH,
C-OR-C-CH,
C-OR
DE1962M0052802 1961-05-15 1962-05-10 Process for the production of the inner ether of pyridoxine Expired DE1470022C3 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US10985361A 1961-05-15 1961-05-15
US16668862A 1962-01-16 1962-01-16

Publications (3)

Publication Number Publication Date
DE1470022A1 DE1470022A1 (en) 1969-01-16
DE1470022B2 DE1470022B2 (en) 1977-07-21
DE1470022C3 true DE1470022C3 (en) 1978-03-09

Family

ID=26807438

Family Applications (1)

Application Number Title Priority Date Filing Date
DE1962M0052802 Expired DE1470022C3 (en) 1961-05-15 1962-05-10 Process for the production of the inner ether of pyridoxine

Country Status (8)

Country Link
BE (1) BE617500A (en)
BR (1) BR6239058D0 (en)
CH (1) CH412889A (en)
DE (1) DE1470022C3 (en)
DK (1) DK104460C (en)
FR (1) FR1323941A (en)
GB (1) GB966805A (en)
SE (1) SE309236B (en)

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3620873A (en) * 1969-03-26 1971-11-16 Ercon Inc Making metal-plastic gasket materials
ATE306489T1 (en) 1999-03-08 2005-10-15 Medicure Inc PYRIDOXAL ANALOGUE FOR THE TREATMENT OF DISORDERS CAUSED BY VITAMIN B6 DEFICIENCY
EP1640005A3 (en) * 1999-03-08 2006-06-07 Medicure International Inc. Pyridoxal analogues for the treatment of disorders caused by a deficiency in vitamin B6
CA2376029A1 (en) 1999-07-13 2001-01-18 Medicure Inc. Use of pyridoxin derivatives for the treatment of diabetes and related complications
JP2003507418A (en) 1999-08-24 2003-02-25 メディキュア インターナショナル インコーポレイテッド Treatment of cardiovascular disease and related diseases
WO2001064692A1 (en) 2000-02-29 2001-09-07 Medicure International Inc. Cardioprotective phosphonates and malonates
US6586414B2 (en) 2000-03-28 2003-07-01 Medicure International Inc. Treatment of cerebrovascular disease
US6548519B1 (en) 2001-07-06 2003-04-15 Medicure International Inc. Pyridoxine and pyridoxal analogues: novel uses
AU2001272263B2 (en) 2000-07-07 2005-12-15 Medicure International Inc. Pyridoxine and pyridoxal analogues: cardiovascular therapeutics
US6897228B2 (en) 2000-07-07 2005-05-24 Medicure International Inc. Pyridoxine and pyridoxal analogues: new uses

Also Published As

Publication number Publication date
GB966805A (en) 1964-08-19
FR1323941A (en) 1963-04-12
SE309236B (en) 1969-03-17
BR6239058D0 (en) 1973-05-24
DE1470022B2 (en) 1977-07-21
CH412889A (en) 1966-05-15
DE1470022A1 (en) 1969-01-16
BE617500A (en) 1962-11-12
DK104460C (en) 1966-05-23

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