CH304886A - Process for preparing 3 ', 5'-dibromo-4-amino-pteroylglutamic acid. - Google Patents
Process for preparing 3 ', 5'-dibromo-4-amino-pteroylglutamic acid.Info
- Publication number
- CH304886A CH304886A CH304886DA CH304886A CH 304886 A CH304886 A CH 304886A CH 304886D A CH304886D A CH 304886DA CH 304886 A CH304886 A CH 304886A
- Authority
- CH
- Switzerland
- Prior art keywords
- acid
- amino
- bromine
- pteroylglutamic
- reaction
- Prior art date
Links
- 238000004519 manufacturing process Methods 0.000 title description 2
- GDTBXPJZTBHREO-UHFFFAOYSA-N bromine Substances BrBr GDTBXPJZTBHREO-UHFFFAOYSA-N 0.000 claims description 13
- WKBOTKDWSSQWDR-UHFFFAOYSA-N Bromine atom Chemical compound [Br] WKBOTKDWSSQWDR-UHFFFAOYSA-N 0.000 claims description 12
- 229910052794 bromium Inorganic materials 0.000 claims description 12
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims description 11
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 9
- 238000000034 method Methods 0.000 claims description 9
- 238000010521 absorption reaction Methods 0.000 claims description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 8
- 150000001875 compounds Chemical class 0.000 claims description 7
- 239000002253 acid Substances 0.000 claims description 6
- 238000006243 chemical reaction Methods 0.000 claims description 6
- TVZGACDUOSZQKY-LBPRGKRZSA-N 4-aminofolic acid Chemical compound C1=NC2=NC(N)=NC(N)=C2N=C1CNC1=CC=C(C(=O)N[C@@H](CCC(O)=O)C(O)=O)C=C1 TVZGACDUOSZQKY-LBPRGKRZSA-N 0.000 claims description 5
- 159000000003 magnesium salts Chemical class 0.000 claims description 5
- 235000011121 sodium hydroxide Nutrition 0.000 claims description 3
- 239000002904 solvent Substances 0.000 claims description 3
- 239000012736 aqueous medium Substances 0.000 claims description 2
- 238000011065 in-situ storage Methods 0.000 claims description 2
- 238000002360 preparation method Methods 0.000 claims description 2
- 239000011541 reaction mixture Substances 0.000 claims description 2
- 239000007787 solid Substances 0.000 claims description 2
- 239000011260 aqueous acid Substances 0.000 claims 1
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 6
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 4
- ZRALSGWEFCBTJO-UHFFFAOYSA-N Guanidine Chemical compound NC(N)=N ZRALSGWEFCBTJO-UHFFFAOYSA-N 0.000 description 4
- 239000000460 chlorine Substances 0.000 description 4
- 229910052801 chlorine Inorganic materials 0.000 description 4
- MUBZPKHOEPUJKR-UHFFFAOYSA-N oxalic acid Substances OC(=O)C(O)=O MUBZPKHOEPUJKR-UHFFFAOYSA-N 0.000 description 4
- 239000000047 product Substances 0.000 description 4
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- SFLOGVVDXPCWGR-UHFFFAOYSA-N leucopterin (keto form) Chemical compound N1C(=O)C(=O)NC2=C1C(=O)N=C(N)N2 SFLOGVVDXPCWGR-UHFFFAOYSA-N 0.000 description 3
- 239000000243 solution Substances 0.000 description 3
- BZSXEZOLBIJVQK-UHFFFAOYSA-N 2-methylsulfonylbenzoic acid Chemical compound CS(=O)(=O)C1=CC=CC=C1C(O)=O BZSXEZOLBIJVQK-UHFFFAOYSA-N 0.000 description 2
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 description 2
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 description 2
- OVBPIULPVIDEAO-UHFFFAOYSA-N N-Pteroyl-L-glutaminsaeure Natural products C=1N=C2NC(N)=NC(=O)C2=NC=1CNC1=CC=C(C(=O)NC(CCC(O)=O)C(O)=O)C=C1 OVBPIULPVIDEAO-UHFFFAOYSA-N 0.000 description 2
- CHJJGSNFBQVOTG-UHFFFAOYSA-N N-methyl-guanidine Natural products CNC(N)=N CHJJGSNFBQVOTG-UHFFFAOYSA-N 0.000 description 2
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 description 2
- 230000015556 catabolic process Effects 0.000 description 2
- 238000006731 degradation reaction Methods 0.000 description 2
- SWSQBOPZIKWTGO-UHFFFAOYSA-N dimethylaminoamidine Natural products CN(C)C(N)=N SWSQBOPZIKWTGO-UHFFFAOYSA-N 0.000 description 2
- 238000004090 dissolution Methods 0.000 description 2
- 238000001914 filtration Methods 0.000 description 2
- OVBPIULPVIDEAO-LBPRGKRZSA-N folic acid Chemical compound C=1N=C2NC(N)=NC(=O)C2=NC=1CNC1=CC=C(C(=O)N[C@@H](CCC(O)=O)C(O)=O)C=C1 OVBPIULPVIDEAO-LBPRGKRZSA-N 0.000 description 2
- 229960000304 folic acid Drugs 0.000 description 2
- 235000019152 folic acid Nutrition 0.000 description 2
- 239000011724 folic acid Substances 0.000 description 2
- HHLFWLYXYJOTON-UHFFFAOYSA-N glyoxylic acid Chemical compound OC(=O)C=O HHLFWLYXYJOTON-UHFFFAOYSA-N 0.000 description 2
- 229910052500 inorganic mineral Inorganic materials 0.000 description 2
- 239000011707 mineral Substances 0.000 description 2
- 235000010755 mineral Nutrition 0.000 description 2
- 150000003195 pteridines Chemical class 0.000 description 2
- VURKRJGMSKJIQX-UHFFFAOYSA-N xanthopterin Chemical compound N1C(=O)C=NC2=C1C(=O)N=C(N)N2 VURKRJGMSKJIQX-UHFFFAOYSA-N 0.000 description 2
- QABAUCFGPWONOG-UHFFFAOYSA-N 2-Amino-4-hydroxy-6-pteridinecarboxylic acid Chemical compound OC(=O)C1=CN=C2NC(N)=NC(=O)C2=N1 QABAUCFGPWONOG-UHFFFAOYSA-N 0.000 description 1
- BMYNFMYTOJXKLE-UHFFFAOYSA-N 3-azaniumyl-2-hydroxypropanoate Chemical compound NCC(O)C(O)=O BMYNFMYTOJXKLE-UHFFFAOYSA-N 0.000 description 1
- 239000005557 antagonist Substances 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 239000004202 carbamide Substances 0.000 description 1
- 239000007795 chemical reaction product Substances 0.000 description 1
- 238000005352 clarification Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- RTZKZFJDLAIYFH-UHFFFAOYSA-N ether Substances CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 1
- 239000000706 filtrate Substances 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 229910052736 halogen Inorganic materials 0.000 description 1
- 150000002367 halogens Chemical class 0.000 description 1
- 230000007062 hydrolysis Effects 0.000 description 1
- 238000006460 hydrolysis reaction Methods 0.000 description 1
- WGCNASOHLSPBMP-UHFFFAOYSA-N hydroxyacetaldehyde Natural products OCC=O WGCNASOHLSPBMP-UHFFFAOYSA-N 0.000 description 1
- 239000000543 intermediate Substances 0.000 description 1
- 239000000395 magnesium oxide Substances 0.000 description 1
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 1
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 235000006408 oxalic acid Nutrition 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- CPNGPNLZQNNVQM-UHFFFAOYSA-N pteridine Chemical compound N1=CN=CC2=NC=CN=C21 CPNGPNLZQNNVQM-UHFFFAOYSA-N 0.000 description 1
- MVKRISPIRVEPFM-UHFFFAOYSA-N pteridine-2,4,6,7-tetrol Chemical compound N1=C(O)C(O)=NC2=NC(O)=NC(O)=C21 MVKRISPIRVEPFM-UHFFFAOYSA-N 0.000 description 1
- WABAALFDOOSQEE-UHFFFAOYSA-N pteridine-6-carboxylic acid Chemical group N1=CN=CC2=NC(C(=O)O)=CN=C21 WABAALFDOOSQEE-UHFFFAOYSA-N 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D475/00—Heterocyclic compounds containing pteridine ring systems
- C07D475/06—Heterocyclic compounds containing pteridine ring systems with a nitrogen atom directly attached in position 4
- C07D475/08—Heterocyclic compounds containing pteridine ring systems with a nitrogen atom directly attached in position 4 with a nitrogen atom directly attached in position 2
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Description
Procédé de préparation de l'acide 3',5'-dibromo-4-amino-ptéroylglutamique. La présente invention concerne la prépa ration de l'acide 3',5'-dibromo-4-amino-ptéroyl- glutamique, qui est un nouveau composé.
Wieland et Purrmann (Ann. 544, 179 [1939]) ont décrit la, réaction de la 2-amino- 4,6,7-trihydroxy-ptéridine (leucoptérine) dans l'acide acétique et l'acide chlorhydrique avec le chlore. On n'a pas établi de façon défini tive la constitution du produit qu'ils obte naient.
On croit cependant que ce pouvait être la 2-imino-5-hydroxy-uramil-7-oxamide. De même, Wieland et Tartter @ (Ann. 543, 287 [1940]) ont décrit la réaction de la 2,4,6,7 tétrahydroxy-ptéridine (désimino-leucoptérine) avec le chlore dans le méthanol. Le produit principal qu'ils obtenaient était l'ester mé thylique de l'acide 5-méthoxy-uramil-7-oxali- que et une petite quantité de sëmi-éther de glycol.
De plus, Scopf et gottler (Ann. 539; 128 [1939]) ont montré que la 2-amino-4,6- dihydroxy-ptéridine (xanthoptérine) est rapi dement attaquée par le chlorate de sodium en solution chlorhydrique à 100 C avec forma- tion, en passant par des intermédiaires, d'acide oxalique, d'acide glyoxylique, de guanidine et d'urée.
On sait également que, quand on traité par l'eau de chlore l'acide 2-amino-4-hydroxy= ptéridine-6-carboxylique, une hydrolyse se produit et qu'on peut déceler de la guanidine (Angier et autres, Science, 103, 667 [1946] ). Whittle et autres (J. A. C.
S. 69; 1786 [1947] ont également montré que le chlorate de so dium réagissait avec l'acide ptéroylglutamique à 80 C pour scinder la molécule et produire l'acide 2-amino-4-hydroxy-ptéridine-6-carboxy- lique et l'acide 4-amino-3,
5-dichlorobenzoyl- glutamique. Il ressort donc de ces publications qu'on a constaté jusqu'ici que l'action des halogènes tels que le .chlore sur les ptéridines substituées conduit à de nombreux produits variés et provoque la dégradation du noyau de ptéridine lui-même.
Le nouveau composé obtenu selon le pro cédé de la présente invention répond à la for mule
EMI0001.0050
Selon l'invention, on prépare ce nouveau composé en faisant réagir l'acide 4-amino- ptéroy1glutamique avec du brome et en sépa- rant du mélange réactionnel - l'acide bromé ainsi obtenu. Le nouveau composé constitue un solide d'un jaune brunâtre, formant un gel en milieu aqueux et donnant un sel de magnésium gra nuleux soluble dans de l'eau chaude.
Dans la soude caustique 0,1N, il présente des maxi mums d'absorption à 259 et 273 mu et des minimums d'absorption à 243 e_t 327 mcc. Dans l'acide chlorhydrique 0,1N, il présente des maximums d'absorption à 283 et 338 mu et des minimums d'absorption à 260 et 320 mu.
On effectue de préférence la réaction dans un solvant tel qu'une solution aqueuse d'un acide minéral à laquelle on peut ajouter di rectement du brome gazeux ou dans un autre solvant convenable tel que l'acide acétique. On peut également former le brome in situ, en utilisant par exemple l'eau oxygénée en présence d'acide bromhydrique.
De préférence, on met en aeuvre le pro cédé selon l'invention à une température com prise d'ans l'intervalle de -10 à<B>+</B> 951, <B>C.</B> Les meilleurs rendements sont obtenus dans. la partie inférieure de l'intervalle indiqué.
Pour la mise en aeuvre du procédé, il est préférable d'utiliser approximativement 2 mo- lécules-gramme de brome par molécule-gramme du composé de départ.
Si on doit utiliser plus de 2 molécules-gramme de brome par molé cule dudit composé, une réaction supplémen taire peut intervenir entre le dérivé dibromé obtenu et l'excès de brome, ce qui peut entraîner mie complète dégradation de la molécule de ptéridine. L'utilisation de moins de 2 molé- culesrgramme de brome conduit également à un mélange de produits finaux.
Le composé préparé selon la présente in vention présenté une activité remarquable comme antagoniste de l'acide ptéroy1glutami- que et a par suite une grande importance, en médecine du point de vue expérimental et pour le traitement de diverses affections. Exemple: On dilue avec 44 cmS d'eau une solution de 4,4 g d'acide 4=amino-ptéroylglutamique dans 44 em3 d'acide chlorhydrique concentré, on refroidit à 0 C et on y fait barboter 3,5 g de vapeur de brome.
Après filtration et lavage a<B>'</B> l'aeid'e chlorhydrique dilué, on met en sus- pension le gâteau dans 1 litre d'eau et on ajoute de la soude caustique pour effectuer la dissolution. On traite la solution par l'acide chlorhydrique jusqu'à un pH de 2 à 3 et on sépare le précipité par filtration. Afin de purifier le produit obtenu, on met à nouveau le gâteau en suspension dans 1 litre d'eau et on ajoute de l'oxyde de magnésium pour pro voquer la dissolution à 60 C..
Après addition de charbon de bois activé et clarification, on refroidit. le filtrat, on sépare par filtration le sel de magnésium précité et on le recristallise dans 1 litre d'eau bouillante. Après refroidis- sement., on filtre le sel de magnésium, on le lave à l'eau et l'acétone et on le sèche. Le sel de magnésium de l'acide 3',5'-dibromo-4-amino- ptéroylglutamique pèse 2,9 g.
L'acide libre est obtenu de manière connue, en traitant le sel de magnésium avec un acide minéral; l'acide ainsi obtenu présente les pro priétés mentionnées plus haut.
Process for preparing 3 ', 5'-dibromo-4-amino-pteroylglutamic acid. The present invention relates to the preparation of 3 ', 5'-dibromo-4-amino-pteroyl-glutamic acid, which is a new compound.
Wieland and Purrmann (Ann. 544, 179 [1939]) have described the reaction of 2-amino-4,6,7-trihydroxy-pteridine (leukopterin) in acetic acid and hydrochloric acid with chlorine. The constitution of the product they obtain has not been definitively established.
It is believed, however, that it could have been 2-imino-5-hydroxy-uramil-7-oxamide. Likewise, Wieland and Tartter® (Ann. 543, 287 [1940]) have described the reaction of 2,4,6,7 tetrahydroxy-pteridine (desimino-leukopterin) with chlorine in methanol. The main product they obtained was 5-methoxy-uramil-7-oxalic acid methyl ester and a small amount of glycol semi-ether.
Moreover, Scopf and gottler (Ann. 539; 128 [1939]) have shown that 2-amino-4,6-dihydroxy-pteridine (xanthopterine) is rapidly attacked by sodium chlorate in hydrochloric solution at 100 C with formation, via intermediates, of oxalic acid, glyoxylic acid, guanidine and urea.
It is also known that, when 2-amino-4-hydroxy = pteridine-6-carboxylic acid is treated with chlorine water, hydrolysis occurs and that guanidine can be detected (Angier et al., Science , 103, 667 [1946]). Whittle et al (J. A. C.
S. 69; 1786 [1947] also showed that sodium chlorate reacted with pteroylglutamic acid at 80 C to split the molecule and produce 2-amino-4-hydroxy-pteridine-6-carboxylic acid and 4-amino-3,
5-dichlorobenzoyl-glutamic. It therefore emerges from these publications that it has hitherto been observed that the action of halogens such as chlorine on substituted pteridines leads to many varied products and causes degradation of the pteridine nucleus itself.
The new compound obtained according to the process of the present invention corresponds to the formula
EMI0001.0050
According to the invention, this new compound is prepared by reacting 4-amino-pteroylglutamic acid with bromine and separating from the reaction mixture - the brominated acid thus obtained. The new compound constitutes a solid of a brownish yellow, forming a gel in aqueous medium and giving a coarse magnesium salt soluble in hot water.
In 0.1N caustic soda, it shows absorption maxima at 259 and 273 mu and absorption minima at 243 e_t 327 mcc. In 0.1N hydrochloric acid, it exhibits absorption maxima at 283 and 338 mu and absorption minima at 260 and 320 mu.
The reaction is preferably carried out in a solvent such as an aqueous solution of a mineral acid to which bromine gas can be added directly or in another suitable solvent such as acetic acid. The bromine can also be formed in situ, for example by using hydrogen peroxide in the presence of hydrobromic acid.
Preferably, the process according to the invention is carried out at a temperature within the range of -10 to <B> + </B> 951, <B> C. </B> The best yields are obtained in. the lower part of the indicated interval.
In carrying out the process, it is preferable to use approximately 2 gram-molecules of bromine per gram-molecule of the starting compound.
If more than 2 gram-molecules of bromine are to be used per molecule of said compound, an additional reaction may take place between the dibromine derivative obtained and the excess bromine, which may lead to complete degradation of the pteridine molecule. The use of less than 2 gram-molecules of bromine also results in a mixture of end products.
The compound prepared according to the present invention exhibits remarkable activity as an antagonist of pteroylglutamic acid and is therefore of great importance, in medicine from the experimental point of view and for the treatment of various conditions. Example: A solution of 4.4 g of 4 = amino-pteroylglutamic acid in 44 em3 of concentrated hydrochloric acid is diluted with 44 cmS of water, it is cooled to 0 C and 3.5 g of steam is bubbled through it. bromine.
After filtration and washing with dilute hydrochloric acid, the cake is suspended in 1 liter of water and caustic soda is added to effect the dissolution. The solution is treated with hydrochloric acid to a pH of 2 to 3 and the precipitate is separated by filtration. In order to purify the product obtained, the cake is again suspended in 1 liter of water and magnesium oxide is added to cause dissolution at 60 ° C.
After addition of activated charcoal and clarification, it is cooled. the filtrate, the aforementioned magnesium salt is filtered off and recrystallized from 1 liter of boiling water. After cooling, the magnesium salt is filtered off, washed with water and acetone and dried. The 3 ', 5'-dibromo-4-amino-pteroylglutamic acid magnesium salt weighs 2.9 g.
The free acid is obtained in a known manner, by treating the magnesium salt with a mineral acid; the acid thus obtained exhibits the properties mentioned above.
Claims (1)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US304886XA | 1950-03-23 | 1950-03-23 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CH304886A true CH304886A (en) | 1955-01-31 |
Family
ID=21854436
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CH304886D CH304886A (en) | 1950-03-23 | 1951-03-21 | Process for preparing 3 ', 5'-dibromo-4-amino-pteroylglutamic acid. |
Country Status (1)
| Country | Link |
|---|---|
| CH (1) | CH304886A (en) |
-
1951
- 1951-03-21 CH CH304886D patent/CH304886A/en unknown
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