CN105481812A - 5-benzyloxy-4-oxo-4H-pyran-2-carboxylic acid preparation method - Google Patents
5-benzyloxy-4-oxo-4H-pyran-2-carboxylic acid preparation method Download PDFInfo
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- CN105481812A CN105481812A CN201510860246.0A CN201510860246A CN105481812A CN 105481812 A CN105481812 A CN 105481812A CN 201510860246 A CN201510860246 A CN 201510860246A CN 105481812 A CN105481812 A CN 105481812A
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- China
- Prior art keywords
- benzyloxy
- oxo
- carboxylic acid
- water
- pyrans
- 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.)
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- 238000002360 preparation method Methods 0.000 title claims abstract description 14
- RGZZNPNSZZJJSH-UHFFFAOYSA-N 4-oxo-5-phenylmethoxypyran-2-carboxylic acid Chemical compound O1C(C(=O)O)=CC(=O)C(OCC=2C=CC=CC=2)=C1 RGZZNPNSZZJJSH-UHFFFAOYSA-N 0.000 title abstract 4
- 238000006243 chemical reaction Methods 0.000 claims abstract description 38
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 claims abstract description 27
- 239000007787 solid Substances 0.000 claims abstract description 21
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 21
- JQWHASGSAFIOCM-UHFFFAOYSA-M sodium periodate Chemical compound [Na+].[O-]I(=O)(=O)=O JQWHASGSAFIOCM-UHFFFAOYSA-M 0.000 claims abstract description 20
- XEKOWRVHYACXOJ-UHFFFAOYSA-N Ethyl acetate Chemical compound CCOC(C)=O XEKOWRVHYACXOJ-UHFFFAOYSA-N 0.000 claims abstract description 18
- 238000003756 stirring Methods 0.000 claims abstract description 18
- BEJNERDRQOWKJM-UHFFFAOYSA-N kojic acid Chemical compound OCC1=CC(=O)C(O)=CO1 BEJNERDRQOWKJM-UHFFFAOYSA-N 0.000 claims abstract description 14
- 229960004705 kojic acid Drugs 0.000 claims abstract description 14
- WZNJWVWKTVETCG-UHFFFAOYSA-N kojic acid Natural products OC(=O)C(N)CN1C=CC(=O)C(O)=C1 WZNJWVWKTVETCG-UHFFFAOYSA-N 0.000 claims abstract description 14
- KCXMKQUNVWSEMD-UHFFFAOYSA-N benzyl chloride Chemical compound ClCC1=CC=CC=C1 KCXMKQUNVWSEMD-UHFFFAOYSA-N 0.000 claims abstract description 8
- 229940073608 benzyl chloride Drugs 0.000 claims abstract description 8
- 238000010992 reflux Methods 0.000 claims abstract description 6
- 239000002904 solvent Substances 0.000 claims abstract description 6
- 238000005406 washing Methods 0.000 claims abstract description 6
- 239000000243 solution Substances 0.000 claims description 20
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims description 10
- 238000004821 distillation Methods 0.000 claims description 10
- 239000012670 alkaline solution Substances 0.000 claims description 5
- 239000000284 extract Substances 0.000 claims description 5
- 239000000706 filtrate Substances 0.000 claims description 5
- 239000000463 material Substances 0.000 claims description 5
- 230000001105 regulatory effect Effects 0.000 claims description 5
- 230000000630 rising effect Effects 0.000 claims description 5
- 238000010792 warming Methods 0.000 claims description 5
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 4
- 239000002351 wastewater Substances 0.000 abstract description 8
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 abstract description 6
- 229910052804 chromium Inorganic materials 0.000 abstract description 5
- 239000011651 chromium Substances 0.000 abstract description 5
- 238000001035 drying Methods 0.000 abstract 3
- 238000001914 filtration Methods 0.000 abstract 2
- 238000010438 heat treatment Methods 0.000 abstract 2
- AYPJBDJTDKSACK-UHFFFAOYSA-N chloromethylbenzene;methanol Chemical compound OC.ClCC1=CC=CC=C1 AYPJBDJTDKSACK-UHFFFAOYSA-N 0.000 abstract 1
- 238000001816 cooling Methods 0.000 abstract 1
- 238000003912 environmental pollution Methods 0.000 abstract 1
- 238000001704 evaporation Methods 0.000 abstract 1
- 238000009776 industrial production Methods 0.000 abstract 1
- 239000003810 Jones reagent Substances 0.000 description 6
- 239000000047 product Substances 0.000 description 5
- 238000000034 method Methods 0.000 description 4
- 238000000926 separation method Methods 0.000 description 3
- 239000002253 acid Substances 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 229940117975 chromium trioxide Drugs 0.000 description 2
- WGLPBDUCMAPZCE-UHFFFAOYSA-N chromium trioxide Inorganic materials O=[Cr](=O)=O WGLPBDUCMAPZCE-UHFFFAOYSA-N 0.000 description 2
- GAMDZJFZMJECOS-UHFFFAOYSA-N chromium(6+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[Cr+6] GAMDZJFZMJECOS-UHFFFAOYSA-N 0.000 description 2
- 229910001385 heavy metal Inorganic materials 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- 206010028980 Neoplasm Diseases 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 125000001797 benzyl group Chemical group [H]C1=C([H])C([H])=C(C([H])=C1[H])C([H])([H])* 0.000 description 1
- 201000011510 cancer Diseases 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 231100000219 mutagenic Toxicity 0.000 description 1
- 230000003505 mutagenic effect Effects 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 239000002689 soil Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D309/00—Heterocyclic compounds containing six-membered rings having one oxygen atom as the only ring hetero atom, not condensed with other rings
- C07D309/34—Heterocyclic compounds containing six-membered rings having one oxygen atom as the only ring hetero atom, not condensed with other rings having three or more double bonds between ring members or between ring members and non-ring members
- C07D309/36—Heterocyclic compounds containing six-membered rings having one oxygen atom as the only ring hetero atom, not condensed with other rings having three or more double bonds between ring members or between ring members and non-ring members with oxygen atoms directly attached to ring carbon atoms
- C07D309/40—Oxygen atoms attached in positions 3 and 4, e.g. maltol
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Pyrane Compounds (AREA)
- Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
Abstract
The present invention discloses a 5-benzyloxy-4-oxo-4H-pyran-2-carboxylic acid preparation method comprising the following steps: adding kojic acid, benzyl chloride and methanol benzyl chloride into a reaction vessel, and heating for reflux reaction for 16 to 18 hours; distilling under reduced pressure, evaporating the solvent to dryness, and cooling to room temperature; adding methanol and water, stirring, washing, filtering and drying to obtain an intermediate; and adding the intermediate and water into the reaction vessel, reducing the temperature to 0 DEG C to -10 DEG C, adding sodium periodate, controlling the temperature to be not higher than 5 DEG C, then adding dropwise a proper amount of water, stirring for 5-15 minutes, heating to 12 DEG C-22 DEG C, stirring for reaction for 2.5 to 3.5 hours, extracting with ethyl acetate, layering, drying, filtering and drying to obtain white solid 5-benzyloxy-4-oxo-4H-pyran-2-carboxylic acid. The new 5-benzyloxy-4-oxo-4H-pyran-2-carboxylic acid preparation method is provided, does not produce large amounts of chromium-containing waste water, prevents severe environmental pollution, and can achieve industrial production.
Description
Technical field
The present invention relates to a kind of preparation method of 5-benzyloxy-4-oxo-4H-pyrans-2-carboxylic acid.
Background technology
Current 5-benzyloxy-4-oxo-4H-pyrans-2-carboxylic acid is chemical industry synthesis, a kind of important intermediate of medicine synthesis, the method of present production 5-benzyloxy-4-oxo-4H-pyrans-2-carboxylic acid mainly connects a benzyl in the oxygen double bond of kojic acid, obtain product 5-benzyloxy-4-oxo-4H-pyrans-2-carboxylic acid carrying out oxidation with Jones reagent, the oxygenant that the method adopts is Jones reagent, in Jones reagent, itself is containing chromium trioxide, whole reaction finally will generate a large amount of waste water, containing chromium in waste water, chromium is heavy metal, chromium not only can cause very serious pollution to ambient soil, and chromium or a kind of strong mutagenic matter, cancer can be brought out and cause deformity.
Summary of the invention
For the problems referred to above of the prior art, the present invention proposes a kind of preparation method of 5-benzyloxy-4-oxo-4H-pyrans-2-carboxylic acid, the invention solves prior art, to prepare 5-benzyloxy-4-oxo-4H-pyrans-2-carboxylic acid waste water content many, product separation cost is high, the technical problem that the purity of product is low.
Chemical equation of the present invention is as follows:
Technical scheme of the present invention is: a kind of preparation method of 5-benzyloxy-4-oxo-4H-pyrans-2-carboxylic acid, comprises the steps:
Step 1, joins kojic acid in reactor, then adds methyl alcohol and dissolved by kojic acid, then adds the alkaline solution of benzyl chloride and appropriate 40%, and temperature rising reflux reaction obtains reaction solution in 16 ~ 18 hours;
Step 2, carries out underpressure distillation by reaction solution, until solvent evaporate to dryness just to be stopped distillation, then is cooled to normal temperature;
Step 3, then distill in step 2 in remaining material and add first alcohol and water, stir, washing, filter, dried by the solid obtained, obtaining lurid solid is intermediate;
Step 4, intermediate is joined in reactor, then add suitable quantity of water, temperature is reduced to 0 DEG C ~-10 DEG C, adds sodium periodate, control temperature is not higher than 5 DEG C, after adding, drip appropriate water, stir after 5-15 minute, be warming up to 12 DEG C ~ 22 DEG C, stirring reaction obtains reaction solution in 2.5 ~ 3.5 hours;
Step 5, reaction solution step 4 obtained filters, and the pH value regulating filtrate with hydrochloric acid is 5 ~ 6, extracts, layering by ethyl acetate, dry, filters, and dried by the solid obtained, obtaining white solid is 5-benzyloxy-4-oxo-4H-pyrans-2-carboxylic acid.
Preferably, in step 1, the mol ratio of kojic acid and benzyl chloride is 1:1 ~ 1:1.2.
Preferably, the volume ratio of the first alcohol and water added after reaction in step 3 is 1:3 ~ 1:5.
Preferably, in step 4, the mol ratio of intermediate and sodium periodate is 1:3 ~ 1:4.
Compared with prior art, the invention has the beneficial effects as follows:
The invention provides a kind of novel method preparing 5-benzyloxy-4-oxo-4H-pyrans-2-carboxylic acid, sodium periodate is adopted to replace Jones reagent in the present invention, a large amount of waste water can be produced after being Jones reagent oxidizing reaction on the one hand, waste water is many, make the complex procedures being separated 5-benzyloxy-4-oxo-4H-pyrans-2-acid product, separation costs is high, and the purity of the 5-benzyloxy-4-oxo-4H-pyrans-2-acid product obtained is lower, the production cost of 5-benzyloxy-4-oxo-4H-pyrans-2-carboxylic acid is caused to increase; And containing chromium trioxide in Jones reagent, containing chromium element in the waste water that reaction produces; Adopt sodium periodate, the water that reaction produces is few, be convenient to be separated 5-benzyloxy-4-oxo-4H-pyrans-2-carboxylic acid, and the purity be separated is larger, save the separation costs of 5-benzyloxy-4-oxo-4H-pyrans-2-carboxylic acid, and not containing heavy metal element environment being caused to severe contamination in waste water, make the standard more meeting environmental protection.
Embodiment
Below in conjunction with embodiment, the technical scheme in the present invention is further illustrated.
Embodiment one
A kind of preparation method of 5-benzyloxy-4-oxo-4H-pyrans-2-carboxylic acid, first 90g kojic acid is joined in the single port flask of 2000ml, add 660ml methyl alcohol again kojic acid is dissolved, then add 80g benzyl chloride and 63ml 40% alkaline solution, temperature rising reflux reacts and obtains reaction solution in 16 hours; Reaction solution is carried out underpressure distillation, until solvent evaporate to dryness just to be stopped distillation, then is cooled to normal temperature; Adding 60ml methyl alcohol and 180ml water to distilling in remaining material again, stirring, washing, filter, dried by the solid obtained, obtaining the lurid solid of 103g is intermediate; 103g intermediate is joined in reactor, then adds 2000ml water, temperature is reduced to 0 DEG C, adds sodium periodate, control temperature, not higher than 5 DEG C, after adding, drips the water of 40ml, stir after 5 minutes, be warming up to 12 DEG C, stirring reaction obtains reaction solution in 2.5 hours; Filtered by the reaction solution obtained, the pH value regulating filtrate with hydrochloric acid is 5 ~ 6, extracts, layering by 500g ethyl acetate, dry, filters, and dried by the solid obtained, obtaining 56g white solid is 5-benzyloxy-4-oxo-4H-pyrans-2-carboxylic acid.
Embodiment two
A kind of preparation method of 5-benzyloxy-4-oxo-4H-pyrans-2-carboxylic acid, first 90g kojic acid is joined in the single port flask of 2000ml, add 660ml methyl alcohol again kojic acid is dissolved, then add 88g benzyl chloride and 63ml 40% alkaline solution, temperature rising reflux reacts and obtains reaction solution in 17 hours; Reaction solution is carried out underpressure distillation, until solvent evaporate to dryness just to be stopped distillation, then is cooled to normal temperature; Adding 60ml methyl alcohol and 240ml water to distilling in remaining material again, stirring, washing, filter, dried by the solid obtained, obtaining the lurid solid of 116g is intermediate; 116g intermediate is joined in reactor, then adds 2000ml water, temperature is reduced to-5 DEG C, add sodium periodate, control temperature, not higher than 5 DEG C, after adding, drips the water of 40ml, stir after 10 minutes, be warming up to 17 DEG C, stirring reaction obtains reaction solution in 3 hours; Filtered by the reaction solution obtained, the pH value regulating filtrate with hydrochloric acid is 5 ~ 6, extracts, layering by 500g ethyl acetate, dry, filters, and dried by the solid obtained, obtaining 80g white solid is 5-benzyloxy-4-oxo-4H-pyrans-2-carboxylic acid.
Embodiment three
A kind of preparation method of 5-benzyloxy-4-oxo-4H-pyrans-2-carboxylic acid, first 90g kojic acid is joined in the single port flask of 2000ml, add 660ml methyl alcohol again kojic acid is dissolved, then add 96g benzyl chloride and 63ml 40% alkaline solution, temperature rising reflux reacts and obtains reaction solution in 18 hours; Reaction solution is carried out underpressure distillation, until solvent evaporate to dryness just to be stopped distillation, then is cooled to normal temperature; Adding 60ml methyl alcohol and 300ml water to distilling in remaining material again, stirring, washing, filter, dried by the solid obtained, obtaining the lurid solid of 116g is intermediate; 116g intermediate is joined in reactor, then adds 2000ml water, temperature is reduced to-10 DEG C, add sodium periodate, control temperature, not higher than 5 DEG C, after adding, drips the water of 40ml, stir after 15 minutes, be warming up to 22 DEG C, stirring reaction obtains reaction solution in 3.5 hours; Filtered by the reaction solution obtained, the pH value regulating filtrate with hydrochloric acid is 5 ~ 6, extracts, layering by 500g ethyl acetate, dry, filters, and dried by the solid obtained, obtaining 80g white solid is 5-benzyloxy-4-oxo-4H-pyrans-2-carboxylic acid.
The foregoing is only preferred embodiment of the present invention, not in order to limit the present invention, within the spirit and principles in the present invention all, any amendment done, equivalent replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (4)
1. a preparation method for 5-benzyloxy-4-oxo-4H-pyrans-2-carboxylic acid, is characterized in that comprising the steps:
Step 1, joins kojic acid in reaction vessel, then adds methyl alcohol and dissolved by kojic acid, then adds the alkaline solution of benzyl chloride and appropriate 40%, and temperature rising reflux reaction obtains reaction solution in 16 ~ 18 hours;
Step 2, carries out underpressure distillation by reaction solution, until solvent evaporate to dryness just to be stopped distillation, then is cooled to normal temperature;
Step 3, then distill in step 2 in remaining material and add first alcohol and water, stir, washing, filter, dried by the solid obtained, obtaining lurid solid is intermediate;
Step 4, intermediate is joined in reactor, then add suitable quantity of water, temperature is reduced to 0 DEG C ~-10 DEG C, adds sodium periodate, control temperature is not higher than 5 DEG C, after adding, drip appropriate water, stir after 5-15 minute, be warming up to 12 DEG C ~ 22 DEG C, stirring reaction obtains reaction solution in 2.5 ~ 3.5 hours;
Step 5, reaction solution step 4 obtained filters, and the pH value regulating filtrate with hydrochloric acid is 5 ~ 6, extracts, layering by ethyl acetate, dry, filters, and dried by the solid obtained, obtaining white solid is 5-benzyloxy-4-oxo-4H-pyrans-2-carboxylic acid.
2. the preparation method of a kind of 5-benzyloxy-4-oxo-4H-pyrans-2-carboxylic acid as claimed in claim 1, is characterized in that: in step 1, the mol ratio of kojic acid and benzyl chloride is 1:1 ~ 1:1.2.
3. the preparation method of a kind of 5-benzyloxy-4-oxo-4H-pyrans-2-carboxylic acid as claimed in claim 1, is characterized in that: the volume ratio of the first alcohol and water added after reaction in step 3 is 1:3 ~ 1:5.
4. the preparation method of a kind of 5-benzyloxy-4-oxo-4H-pyrans-2-carboxylic acid as claimed in claim 1, is characterized in that: in step 4, the mol ratio of intermediate and sodium periodate is 1:3 ~ 1:4.
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| CN201510860246.0A CN105481812B (en) | 2015-11-30 | 2015-11-30 | Preparation method of 5-benzyloxy-4-oxo-4H-pyran-2-carboxylic acid |
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| CN105481812B CN105481812B (en) | 2020-04-21 |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109438405A (en) * | 2018-12-24 | 2019-03-08 | 广东莱佛士制药技术有限公司 | A kind of synthetic method of 3- (benzyloxy) -4- oxo -4H- pyrans -2- carboxylic acid |
| WO2020132820A1 (en) * | 2018-12-24 | 2020-07-02 | 广东莱佛士制药技术有限公司 | Synthesis method for 3-(benzyloxy)-4-oxo-4h-pyran-2-carboxylic acid |
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| US5891892A (en) * | 1996-10-29 | 1999-04-06 | Warner-Lambert Company | Small molecule biaryl compounds as inhibitors of endothelin converting enzyme |
| CN102325769A (en) * | 2008-12-19 | 2012-01-18 | 美国辉瑞有限公司 | Monocarbams |
| CN102869256A (en) * | 2010-03-04 | 2013-01-09 | 默沙东公司 | Inhibitors of catechol O-methyl transferase and their use in the treatment of psychotic disorders |
| CN103228652A (en) * | 2010-11-29 | 2013-07-31 | 辉瑞大药厂 | monocyclic lactams |
-
2015
- 2015-11-30 CN CN201510860246.0A patent/CN105481812B/en not_active Expired - Fee Related
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5891892A (en) * | 1996-10-29 | 1999-04-06 | Warner-Lambert Company | Small molecule biaryl compounds as inhibitors of endothelin converting enzyme |
| CN102325769A (en) * | 2008-12-19 | 2012-01-18 | 美国辉瑞有限公司 | Monocarbams |
| CN102869256A (en) * | 2010-03-04 | 2013-01-09 | 默沙东公司 | Inhibitors of catechol O-methyl transferase and their use in the treatment of psychotic disorders |
| CN103228652A (en) * | 2010-11-29 | 2013-07-31 | 辉瑞大药厂 | monocyclic lactams |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109438405A (en) * | 2018-12-24 | 2019-03-08 | 广东莱佛士制药技术有限公司 | A kind of synthetic method of 3- (benzyloxy) -4- oxo -4H- pyrans -2- carboxylic acid |
| WO2020132820A1 (en) * | 2018-12-24 | 2020-07-02 | 广东莱佛士制药技术有限公司 | Synthesis method for 3-(benzyloxy)-4-oxo-4h-pyran-2-carboxylic acid |
| CN109438405B (en) * | 2018-12-24 | 2023-04-07 | 广东莱佛士制药技术有限公司 | Synthetic method of 3- (benzyloxy) -4-oxo-4H-pyran-2-carboxylic acid |
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| CN105481812B (en) | 2020-04-21 |
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