CN103420927A - Synthetic method of quinoxaline-2-carboxylic acid - Google Patents
Synthetic method of quinoxaline-2-carboxylic acid Download PDFInfo
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- CN103420927A CN103420927A CN2013102263914A CN201310226391A CN103420927A CN 103420927 A CN103420927 A CN 103420927A CN 2013102263914 A CN2013102263914 A CN 2013102263914A CN 201310226391 A CN201310226391 A CN 201310226391A CN 103420927 A CN103420927 A CN 103420927A
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- quinoxaline
- carboxylic acid
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- formaldehyde
- oxoquinoxaline
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Abstract
The invention belongs to the technical field of veterinary medicine preparation, and particularly relates to a synthetic method of Kappa oxygen residual marker quinoxaline-2-carboxylic acid for detecting veterinary drug residues. The preparation of the quinoxaline-2-carboxylic acid comprises the following steps: (1) using o-phenylenediamine as a raw material to be subjected to condensation with methylglyoxal to obtain an intermediate product 2-methyl-quinoxaline; (2) performing oxidation reaction on the intermediate product 2-methyl-quinoxaline by using selenium dioxide to obtain quinoxaline-2-formaldehyde; (3) performing further oxidation on the quinoxaline-2-formaldehyde by using acidic potassium permanganate to obtain a target product quinoxaline-2-carboxylic acid. The synthetic method provided by the invention has the advantages of reasonable design of reaction procedures, simple operation and higher yield.
Description
Technical field
The invention belongs to technical field of animal remedy preparation, be specifically related to the chemical synthesis process of a kind of Oxoquinoxaline-2-carboxylic acid (QCA).
Background technology
Carbadox belongs to quinoxaline-1, and 4-dioxide class medicine is that Pfizer Inc. is in synthetic broad spectrum antibiotic of nineteen seventies.In European Union, many countries such as North America once were widely used in poultry, fowl, aquaculture as antivirus somatotropic agent.In recent years the carbadox toxicologic study is shown, carbadox and a de-oxygen thereof and de-dioxy metabolite have stronger toxic action, main manifestations be carcinogenic, mutagenesis, breeding toxicity and hepatotoxicity etc. (
Et al, 1993:Yoshimura etal, 1981; Scheutwinkel-Reich et al, 1984).Given this, European Union forbids that in 1999 carbadox and olaquindox are for the antibiotic growth promotion of animal, even also the use of carbadox and olaquindox has been made to strict regulation in the U.S..Comprise the quinoxaline medicine carbadox in China Ministry of Agriculture clear forbidding veterinary drug catalogue.One of metabolite that Oxoquinoxaline-2-carboxylic acid is carbadox, be defined as the residual marker of carbadox (seeing JECFA the 36th session (1991)) at present.
For ensuring food safety, guarantee the normal trade contact of China's animal food, the Ministry of Agriculture and The State Administration for Entry-Exit Inspection and Quarantine have formulated successively 3-Jia based quinoxaline-2-carboxylic acid in animal-derived food with Oxoquinoxaline-2-carboxylic acid remained examination criteria (GB/T20746-2006, the mensuration Liquid Chromatography-Tandem Mass Spectrometry of carbadox and olaquindox and metabolite residue amount in the liver of ox, pig and muscle; 06 year 781-3 of the Ministry of Agriculture, 3-Jia based quinoxaline-2-carboxylic acid in animal-derived food is with the mensuration high performance liquid chromatography of Oxoquinoxaline-2-carboxylic acid remained amount; In No. 236 bulletin [2003] animal-derived foods of the Ministry of Agriculture, carbadox indicates the residue detection method).The formulation of these standards provides technical support for the detection of animal food Zhong Oxoquinoxaline-2-carboxylic acid, but State center for standard matter and veterinary drug supervision do not have Oxoquinoxaline-2-carboxylic acid (QCA) standard substance all the time, and the high-purity compound that mostly adopts Sigma company to provide in contrast product for residue detection, so synthesize Oxoquinoxaline-2-carboxylic acid (QCA) and further make qualified reference material and become the task of top priority.
The current bibliographical information synthetic about Oxoquinoxaline-2-carboxylic acid is as follows:
1) Wong of Pfizer Inc.; John W. etc. adopt Pseudomonas putida (ATCC33015); bio-transformation 2-Jia based quinoxaline synthesizes quinoxaline-2-formic acid (Wong; John W.et al.Biocatalytic oxidation of 2-methylquinoxaline to 2-quinoxalinecarboxylic acid, Organic Process Research & Development, 6 (4), 477-481; 2002).
The method adopts the synthetic QCA of biofermentation method, avoid using poisonous and harmful chemical reagent and productive rate higher, but the bacterial classification Pseudomonas putida (ATCC33015) adopted originates, difficult price is high and culture condition is harsh, under usual terms, is difficult to realize amplifying produce.
2) Harms; it is raw material that Arthur E. etc. be take 2-Jia based quinoxaline; through with benzaldehyde after adopt potassium permanganate oxidation to obtain target product QCA (Harms, Arthur E.An Efficient Synthesis of 2-Quinoxalinecarboxylic Acid.Organic Process Research & Development, 8 (4), 666-669; 2004).The method is by adopting potassium permanganate to obtain carboxylic acid to the carbon-carbon double bond oxidation of intermediate, a kind of feasible way of can yet be regarded as, but need to use benzaldehyde and obtain intermediate 2-vinylbenzene quinoxaline, significantly increase reactions steps, cause last overall yield lower.
3) Kepez, the report such as Mustafa is with 2,3-dimethyl quinoxaline is raw material, adopt tin anhydride oxidation single step reaction to obtain target product QCA (Kepez, Mustafa.Oxidation of 2,3-dimethylquinoxaline and 2,4-dimethylquinazoline with selenium dioxide.Monatshefte fuer Chemie, 120 (2), 127-30; 1989).The method is made solvent at dimethylbenzene, with tin anhydride, at high temperature two methyl oxidations on the quinoxaline ring is become to carboxyl, and decarboxylation simultaneously generates target product QCA, and method is comparatively easy, but reaction conditions requires high and productive rate is too low.
Summary of the invention
The object of the invention is to overcome the deficiencies in the prior art, and a kind of chemical synthesis process of the standard substance Oxoquinoxaline-2-carboxylic acid for detecting the carbadox residue detection is provided, and the method raw material is easy to get, easy and simple to handle.
Realize that general technical route of the present invention is:
The present invention carries out condensation with O-Phenylene Diamine and pyruvic aldehyde, obtains intermediate product 2-Jia based quinoxaline, and the intermediate 2-Jia based quinoxaline of generation is carried out to oxidizing reaction with tin anhydride again, generates quinoxaline-2-formaldehyde; After this by obtaining the further oxidation of acid potassium permanganate for De quinoxaline-2-formaldehyde, obtain the target product Oxoquinoxaline-2-carboxylic acid.
Particularly, synthetic method of the present invention comprises the following steps:
1) add O-Phenylene Diamine in there-necked flask, make it to dissolve with methyl alcohol, be heated to reflux; By waiting amount of substance to get 40% pyruvic aldehyde, with methanol solution, make it dilution afterwards, slowly splash in there-necked flask, back flow reaction 16～20h, filter; Filtrate evaporated under reduced pressure after drying obtain the intermediate 2-Jia based quinoxaline of faint yellow oily mater; As preferred version, pyruvic aldehyde should be excessive slightly;
2) the 2-Jia based quinoxaline that is 1: 1.2 by the amount of substance ratio and tin anhydride are dissolved in ethyl acetate or other suitable solvents, back flow reaction 4～6h, filter, and after the filtrate decompression solvent evaporated, adds appropriate ethyl acetate to make to dissolve, standing, crystallization obtains khaki intermediate quinoxaline-2-formaldehyde;
3) be that 1: 1～5: 1 De quinoxaline-2-formaldehyde and potassium permanganate are dissolved in pyridine by the amount of substance ratio, add afterwards dilute sulphuric acid, room temperature reaction 16～20h, filter; Filtrate adds a small amount of distilled water, boils off most of pyridine; Adjust pH=8～9 with sodium hydroxide afterwards, ethyl acetate extraction three times, abandon organic phase; The water ice bath, hydrochloric acid is adjusted pH=2～3, a large amount of precipitations occur, filters and obtain the solid Oxoquinoxaline-2-carboxylic acid.
Said synthesis route has the following advantages:
1, raw material is easy to get: raw material used in the present invention and reagent O-Phenylene Diamine, hydrochloric acid, potassium permanganate, sodium hydroxide, methyl alcohol, ethyl acetate, anhydrous magnesium sulfate etc. are all raw material commonly used and reagent, easily obtain.
2, the easy realization such as conversion unit, operational condition and productive rate are stable, suitable further amplification production.
The accompanying drawing explanation
Fig. 1: the biosynthesizing route that is the report De of prior art Pfizer Inc. quinoxaline-2-formic acid (QCA).In figure: the English of top is that strain name is Pseudomonas putida, and in bracket, for strain number is ATCC33015, Reference numeral is: R:PhCH
2OH, S:Glycerol 1.R:NH
4Cl, R:(NH
4)
2SO
4.
Fig. 2: be prior art Harms, the synthetic route of Arthur E. report De quinoxaline-2-formic acid (QCA).
Fig. 3: be prior art Kepez, the synthetic route of the report such as Mustafa De quinoxaline-2-formic acid (QCA).
Fig. 4: the synthetic route that is quinoxaline of the present invention-2-formic acid (QCA).
Fig. 5: be the UV scanning collection of illustrative plates (take methyl alcohol as solvent) that the present invention prepares the gained Oxoquinoxaline-2-carboxylic acid.
Fig. 6: the present invention prepares the infared spectrum (KBr compressing tablet) of gained Oxoquinoxaline-2-carboxylic acid.
Fig. 7: the present invention prepares the gained Oxoquinoxaline-2-carboxylic acid
1HNMR collection of illustrative plates (CDCl
3).
Fig. 8: the present invention prepares the mass spectrum (ESI, negative ion mode) of gained Oxoquinoxaline-2-carboxylic acid.
Embodiment
Add O-Phenylene Diamine 10.8g in there-necked flask, make it to dissolve with methyl alcohol 200mL, be heated to reflux; Get afterwards 40% pyruvic aldehyde 18g, with methyl alcohol 50mL, make it dilution, slowly splash in there-necked flask; Back flow reaction 16～20h, filter; Anhydrous magnesium sulfate drying, filter, and boils off methyl alcohol, obtains faint yellow oily mater 2-Jia based quinoxaline 12g (productive rate 83%).
Add 2-Jia based quinoxaline 10g in there-necked flask, take ethyl acetate as solvent, be heated to reflux, add afterwards tin anhydride 11g altogether; Back flow reaction 4～6h, filter, and filtrate boils off a large amount of ethyl acetate, is positioned under 4 ℃ of conditions, carries out recrystallization, obtains khaki intermediate quinoxaline-2-formaldehyde 8.3g (productive rate 76%).
Add products therefrom quinoxaline-2-formaldehyde 2.2g in the single port flask, make it to dissolve with pyridine 20mL; Add afterwards potassium permanganate 0.42g and 3molL
-1Sulfuric acid 6mL, room temperature reaction 16～20h, filter; Filtrate adds a small amount of distilled water, boils off most of pyridine; Use afterwards 2molL
-1Sodium hydroxide adjust pH to 8～9, ethyl acetate extraction three times, abandon organic phase; The water ice bath, use 4molL
-1Hydrochloric acid adjust pH to 2～3, a large amount of precipitations appear, filter and obtain solid Oxoquinoxaline-2-carboxylic acid 1.6g (productive rate 67%).
Embodiment 2
Add O-Phenylene Diamine 21.6g in there-necked flask, make it to dissolve with methyl alcohol 250mL, be heated to reflux; Get afterwards 40% pyruvic aldehyde 36g, with methyl alcohol 100mL, make it dilution, slowly splash in there-necked flask; Back flow reaction 16～20h, filter; Anhydrous magnesium sulfate drying, filter, and boils off methyl alcohol, obtains faint yellow oily mater 2-Jia based quinoxaline 25.2g (productive rate 88%).
Add 2-Jia based quinoxaline 20g in there-necked flask, take Isosorbide-5-Nitrae-dioxane as solvent, be heated to 90 ℃, gradation adds tin anhydride 10g altogether; Stirring reaction 4～6h, filter, and filtrate boils off a large amount of solvents, with after appropriate ethyl acetate solvent in 4 ℃ of placements, crystallization, obtain khaki intermediate quinoxaline-2-formaldehyde 15.8g (productive rate 72%).
Add product quinoxaline-2-formaldehyde 5g in the single port flask, make it to dissolve with pyridine 20mL; Add afterwards potassium permanganate 0.42g and 3molL
-1Sulfuric acid 6mL, room temperature reaction 16～20h, filter; Filtrate adds a small amount of distilled water, boils off most of pyridine; Use afterwards 2molL
-1Sodium hydroxide adjust pH to 8～9, ethyl acetate extraction three times, abandon organic phase; The water ice bath, use 4molL
-1Hydrochloric acid adjust pH to 2～3, a large amount of precipitations appear, filter and obtain solid Oxoquinoxaline-2-carboxylic acid 3.8g (productive rate 69%).
Embodiment 3
Product prepared by the present invention is as follows through ultraviolet, infrared, nucleus magnetic resonance, mass spectrometry method detected result:
Fig. 1 is shown in by the UV scanning collection of illustrative plates (MeOH) of Oxoquinoxaline-2-carboxylic acid.
Fig. 2 is shown in by the infrared scan collection of illustrative plates (pressing potassium bromide troche) of Oxoquinoxaline-2-carboxylic acid.In figure: the corresponding relation of each main absorption peak and each group is: 3452cm
-1, υ
OHThe stretching vibration of carboxylic hydroxyl; 3071cm
-1, υ
C-HPhenyl ring C-H stretching vibration; 1707cm
-1, υ
C=OCarbonylic stretching vibration; 1498cm
-1, 1467cm
-1Phenyl ring C=C stretching vibration.
Oxoquinoxaline-2-carboxylic acid
1HNMR spectrogram (Mercury400 nuclear magnetic resonance analyser, deuterium is solvent for trichloromethane) is shown in Fig. 3.In figure: 7.260ppm is the solvent deuterium for trichloromethane
1The chemical shift of H; 3.180ppm be-CH
3H-shift; 7.826 the H-shift that～8.155ppm is the quinoxaline group; 8.6～12.0ppm broad peak is the chemical shift of-COOH association hydrogen bond.
Oxoquinoxaline-2-carboxylic acid mass spectrum (LC/MS-IT-TOF mass spectrograph) is shown in Fig. 4 (200 ℃ of source temperature, electron energy 1.7KV, quality of scanning scope 125-225Da, negative ion mode).In figure: the molecular ion peak of m/z173.0388 Wei Oxoquinoxaline-2-carboxylic acid; M/z129.0483 is that molion is sloughed CO
2The fragment ion peak of molecule.
Claims (1)
1. the synthetic method of an Oxoquinoxaline-2-carboxylic acid, it is characterized in that following steps: adopt O-Phenylene Diamine and pyruvic aldehyde to carry out obtaining intermediate product 2-Jia based quinoxaline after condensation reaction, intermediate 2-Jia based quinoxaline and the tin anhydride of generation are carried out to oxidizing reaction, De quinoxaline-2-formaldehyde, finally quinoxaline-2-formaldehyde is carried out to oxidation with potassium permanganate under acidic conditions, obtain the target product Oxoquinoxaline-2-carboxylic acid;
Synthesis step is as follows:
(1) get O-Phenylene Diamine, make it to dissolve with methyl alcohol or ethanol, then 40% the pyruvic aldehyde of measuring than 1: 1 by amount of substance, slowly splash in reaction solution, after back flow reaction 16～20h, stopped reaction, the reaction solution evaporated under reduced pressure obtains the intermediate 2-Jia based quinoxaline of faint yellow oily mater;
(2) upper step reaction product is dissolved in to solvent acetonitrile, ethyl acetate, methylene dichloride or dioxane, taking tin anhydride by 1.2 times of amount of substances adds in reaction solution, after back flow reaction 4～6h, stopped reaction, after boiling off most of solvent by reaction solution, in 4 ℃ standing, separate out khaki color crystallization Ji quinoxaline-2-formaldehyde;
(3) being dissolved in pyridine of to be 3: 1 by the amount of substance ratio measure quinoxaline-2-formaldehyde and oxidant potassium permanganate, with dilute sulphuric acid or dilute hydrochloric acid, adjust solution to acid, after at room temperature reacting 16～20h, filter, filtrate is adjusted pH to 8～9 with sodium hydroxide solution after boiling off most of pyridine, is extracted with ethyl acetate three times, discard organic phase, water intaking is adjusted to pH2～3 with dilute hydrochloric acid, separates out precipitation, filters and obtain the product Oxoquinoxaline-2-carboxylic acid.
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Cited By (5)
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| CN104710371A (en) * | 2013-12-13 | 2015-06-17 | 江南大学 | Preparation method of trifluoromethyl-containing benzo pyrazinamide |
| CN105061338A (en) * | 2014-11-20 | 2015-11-18 | 平原县伟峰永驻科技有限公司 | 3-methyl-quinoxaline-2-carboxylic acid chemical synthesis method based on ionic liquid system |
| WO2017072039A1 (en) | 2015-10-26 | 2017-05-04 | Bayer Cropscience Aktiengesellschaft | Condensed bicyclic heterocycle derivatives as pest control agents |
| CN110218195A (en) * | 2018-03-02 | 2019-09-10 | 上海安谱实验科技股份有限公司 | A kind of quinoxaline -2- the carboxylic acid and its synthetic method of stable isotope labeling |
| CN110642797A (en) * | 2018-06-26 | 2020-01-03 | 上海出入境检验检疫局动植物与食品检验检疫技术中心 | Synthesis method of stable isotope labeled quinoxaline-2-carboxylic acid |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104710371A (en) * | 2013-12-13 | 2015-06-17 | 江南大学 | Preparation method of trifluoromethyl-containing benzo pyrazinamide |
| CN105061338A (en) * | 2014-11-20 | 2015-11-18 | 平原县伟峰永驻科技有限公司 | 3-methyl-quinoxaline-2-carboxylic acid chemical synthesis method based on ionic liquid system |
| WO2017072039A1 (en) | 2015-10-26 | 2017-05-04 | Bayer Cropscience Aktiengesellschaft | Condensed bicyclic heterocycle derivatives as pest control agents |
| CN110218195A (en) * | 2018-03-02 | 2019-09-10 | 上海安谱实验科技股份有限公司 | A kind of quinoxaline -2- the carboxylic acid and its synthetic method of stable isotope labeling |
| CN110218195B (en) * | 2018-03-02 | 2022-08-09 | 上海安谱实验科技股份有限公司 | Stable isotope labeled quinoxaline-2-carboxylic acid and synthesis method thereof |
| CN110642797A (en) * | 2018-06-26 | 2020-01-03 | 上海出入境检验检疫局动植物与食品检验检疫技术中心 | Synthesis method of stable isotope labeled quinoxaline-2-carboxylic acid |
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