CN111303158A - Preparation method of (4-chloro-1H-pyrazoline [3,4-d ] pyrimidine-3-yl) aryl ketone - Google Patents
Preparation method of (4-chloro-1H-pyrazoline [3,4-d ] pyrimidine-3-yl) aryl ketone Download PDFInfo
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- CN111303158A CN111303158A CN202010273953.0A CN202010273953A CN111303158A CN 111303158 A CN111303158 A CN 111303158A CN 202010273953 A CN202010273953 A CN 202010273953A CN 111303158 A CN111303158 A CN 111303158A
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- C07—ORGANIC CHEMISTRY
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- C07D487/00—Heterocyclic compounds containing nitrogen atoms as the only ring hetero atoms in the condensed system, not provided for by groups C07D451/00 - C07D477/00
- C07D487/02—Heterocyclic compounds containing nitrogen atoms as the only ring hetero atoms in the condensed system, not provided for by groups C07D451/00 - C07D477/00 in which the condensed system contains two hetero rings
- C07D487/04—Ortho-condensed systems
Abstract
The invention provides a preparation method of (4-chloro-1H-pyrazoline [3,4-d ] pyrimidine-3-yl) aryl ketone, which is characterized in that 3-bromo-4-chloro-1H-pyrazoline [3,4-d ] pyrimidine is used as a raw material, and is subjected to one-step condensation with an acyl chloride compound to prepare a target product compound (4-chloro-1H-pyrazoline [3,4-d ] pyrimidine-3-yl) aryl ketone (shown in a formula A); the preparation method of the (4-chloro-1H-pyrazoline [3,4-d ] pyrimidine-3-yl) aryl ketone has the advantages of short reaction route, less side reaction and easy purification of products, improves the yield of the whole synthesis route, and is beneficial to large-scale production and industrial popularization.
Description
Technical Field
The invention relates to the technical field of organic compound synthesis, in particular to a preparation method of (4-chloro-1H-pyrazoline [3,4-d ] pyrimidine-3-yl) aryl ketone.
Background
The (4-chloro-1H-pyrazoline [3,4-d ] pyrimidine-3-yl) aryl ketone, the active core pyrimidine ring and pyrazoline ring contain a plurality of nitrogen heteroatoms, and are important intermediate compounds for synthesizing a plurality of novel pharmaceutical compounds containing nitrogen heteroatoms or pyrimidine rings and pyrazoline rings. The (4-chloro-1H-pyrazoline [3,4-d ] pyrimidin-3-yl) aryl ketone has the following structure:
through the search of the prior art, no report is found for disclosing the preparation method of the (4-chloro-1H-pyrazoline [3,4-d ] pyrimidine-3-yl) aryl ketone; the prior art discloses that pyrazoline pyrimidine fused ring compounds are generally prepared by a ring closing method, and the preparation method has the disadvantages of long route, poor selectivity and more side reactions, which leads to extremely difficult separation and purification of products and low yield; the reaction conditions are harsh, the safety is poor, and the method is not suitable for industrial scale-up production and industrial application.
Therefore, the technical personnel in the field are devoted to develop a preparation method of (4-chloro-1H-pyrazoline [3,4-d ] pyrimidine-3-yl) aryl ketone, aiming at solving the defects of the preparation method of the compound in the prior art.
Disclosure of Invention
The technical problems to be solved by the invention are that the preparation method of (4-chloro-1H-pyrazoline [3,4-d ] pyrimidine-3-yl) aryl ketone in the prior art has the disadvantages of long reaction route, poor selectivity, more side reactions, extremely difficult separation and purification of products, low yield, harsh reaction conditions and poor safety, and is not suitable for industrial scale-up production and industrial application.
In order to achieve the above objects, the present invention provides a method for preparing (4-chloro-1H-pyrazoline [3,4-d ] pyrimidin-3-yl) aryl ketone, wherein the structure of the (4-chloro-1H-pyrazoline [3,4-d ] pyrimidin-3-yl) aryl ketone is represented by the following formula A,
the preparation method of the (4-chloro-1H-pyrazoline [3,4-d ] pyrimidine-3-yl) aryl ketone has a route shown in the following scheme I:
route I:
wherein R, R' are each independently selected from hydrogen, halogen, C1-C10 alkyl, C5-C15 aryl, C1-C10 alkoxy, C5-C15 aryloxy;
the preparation method of the (4-chloro-1H-pyrazoline [3,4-d ] pyrimidine-3-yl) aryl ketone comprises the following specific operation steps: dissolving a compound A-1 in an oxygen-containing nonpolar solvent, cooling to-78 ℃ in an inert gas environment, adding an alkyl lithium reagent, stirring for 30-60 minutes, adding a compound A-2, keeping a reaction solution at-78 ℃ for reaction, stirring for 30-60 minutes, heating to room temperature, and continuing stirring for reaction for 2-3 hours; adding water into the reaction solution for quenching, adding an organic solvent for extraction, washing an organic phase, drying, filtering, concentrating to remove the organic solvent, and purifying by column chromatography to obtain a target product (4-chloro-1H-pyrazoline [3,4-d ] pyrimidin-3-yl) aryl ketone compound (formula A);
further, the halogen is fluorine, chlorine, bromine;
further, the alkyl group is linear or branched or cyclic;
further, the aryl is aliphatic aryl of C5-C15, heterocyclic aryl containing 1-10 carbon atoms;
further, the alkyl, aryl, alkoxy, aryloxy are unsubstituted or substituted with one or more substituents selected from the group consisting of: halogen, hydroxy, cyano, carbonyl, mercapto, alkylthio, acylamino, aliphatic hydrocarbyl, aryl;
further, each of said R, R' is independently selected from hydrogen, fluoro, chloro, bromo, methyl, ethyl, propyl, isopropyl, cyclopropyl, butyl, isobutyl, cyclobutyl, cyclopentyl, cyclohexyl, phenyl, pyridyl, pyrimidinyl, pyrrolyl, pyrazolyl, methoxy, ethoxy, phenoxy; wherein said methyl, ethyl, propyl, isopropyl, cyclopropyl, butyl, isobutyl, cyclobutyl, cyclopentyl, cyclohexyl, phenyl, pyridyl, pyrimidinyl, pyrrolyl, pyrazolyl, methoxy, ethoxy, phenoxy are unsubstituted or substituted by one or more substituents selected from the group consisting of: alkyl, halogen, aryl;
further, each of said R, R' is independently selected from hydrogen, fluoro, chloro, bromo, methyl, ethyl, propyl, isopropyl, methoxy, ethoxy, phenoxy;
according to the preparation method of the (4-chloro-1H-pyrazoline [3,4-d ] pyrimidine-3-yl) aryl ketone, the oxygen-containing nonpolar solvent is tetrahydrofuran, dioxane, diethyl ether and methyl tert-butyl ether; preferably tetrahydrofuran;
according to the preparation method of the (4-chloro-1H-pyrazoline [3,4-d ] pyrimidin-3-yl) aryl ketone, the alkyl lithium reagent is n-butyl lithium, isobutyl lithium, sec-butyl lithium or tert-butyl lithium; preferably n-butyllithium;
according to the preparation method of the (4-chloro-1H-pyrazoline [3,4-d ] pyrimidine-3-yl) aryl ketone, the organic solvent is dichloromethane, ethyl acetate, diethyl ether and methyl tert-butyl ether; preferably ethyl acetate;
according to the preparation method of the (4-chloro-1H-pyrazoline [3,4-d ] pyrimidine-3-yl) aryl ketone, the molar ratio of the compound A-1 to the compound A-2 is 1: 1-1: 1.5;
according to the preparation method of the (4-chloro-1H-pyrazoline [3,4-d ] pyrimidine-3-yl) aryl ketone, the weight-volume ratio (g/ml) of the compound A-1 to the oxygen-containing nonpolar solvent is 1: 10-1: 20;
according to the preparation method of the (4-chloro-1H-pyrazoline [3,4-d ] pyrimidine-3-yl) aryl ketone, the volume ratio (g/ml) of the compound A-1 to an alkyl lithium reagent is 1: 4-1: 8;
according to a preferred embodiment of the process for preparing (4-chloro-1H-pyrazolin [3,4-d ] pyrimidin-3-yl) aryl methanones according to the present invention, the molar ratio of compound A-1 to compound A-2 is 1: 1;
according to a preferred embodiment of the process for preparing (4-chloro-1H-pyrazolin [3,4-d ] pyrimidin-3-yl) aryl methanones according to the present invention, the molar ratio of compound A-1 to compound A-2 is 1: 1.1;
according to a preferred embodiment of the process for preparing (4-chloro-1H-pyrazolin [3,4-d ] pyrimidin-3-yl) aryl methanones according to the present invention, the molar ratio of compound A-1 to compound A-2 is 1: 1.5;
according to a preferred embodiment of the process for the preparation of (4-chloro-1H-pyrazolin [3,4-d ] pyrimidin-3-yl) aryl methanones according to the present invention, the weight to volume ratio (g/ml) of said compound a-1 to the oxygen-containing non-polar solvent is 1: 10;
according to a preferred embodiment of the process for the preparation of (4-chloro-1H-pyrazolin [3,4-d ] pyrimidin-3-yl) aryl methanones according to the present invention, the weight to volume ratio (g/ml) of said compound a-1 to the oxygen-containing non-polar solvent is 1: 15;
according to a preferred embodiment of the process for the preparation of (4-chloro-1H-pyrazolin [3,4-d ] pyrimidin-3-yl) aryl methanones according to the present invention, the weight to volume ratio (g/ml) of said compound a-1 to the oxygen-containing non-polar solvent is 1: 20;
according to a preferred embodiment of the process for the preparation of (4-chloro-1H-pyrazolin [3,4-d ] pyrimidin-3-yl) aryl methanones according to the invention, the volume ratio (g/ml) of said compound a-1 to the alkyllithium reagent is 1: 4;
according to a preferred embodiment of the process for the preparation of (4-chloro-1H-pyrazolin [3,4-d ] pyrimidin-3-yl) aryl methanones according to the invention, the volume ratio (g/ml) of said compound a-1 to the alkyllithium reagent is 1: 6;
according to a preferred embodiment of the process for the preparation of (4-chloro-1H-pyrazolin [3,4-d ] pyrimidin-3-yl) aryl methanones according to the invention, the volume ratio (g/ml) of said compound a-1 to the alkyllithium reagent is 1: 8;
the technical parameter characteristics in the above preparation method of the present invention can be combined at will.
In a preferred embodiment of the present invention, the quenching is a process of adding a quencher to the reaction solution to stop the reaction from proceeding to the right;
the quenching agent is water or ice water;
in a preferred embodiment of the present invention, the filtration refers to a process of separating solids and liquids in a reaction solution, or a process of separating solids and liquids in a post-treatment operation; the filtration comprises common filtration and separation and centrifugal separation; wherein, the common filtration separation includes but is not limited to filtration by using filter paper, filter cloth, filter membrane filtration and diatomite filtration;
in a preferred embodiment of the present invention, the drying comprises anhydrous sodium sulfate drying, vacuum drying of the filtrate;
in a preferred embodiment of the present invention, the concentration refers to a process of removing a liquid solvent, including concentration under reduced pressure, concentration under normal pressure, low-temperature spin-drying, etc.;
in a preferred embodiment of the present invention, the inert gas environment is a nitrogen gas environment or an argon gas environment;
the steps, solvents, reagents, filtration, drying, concentration, extraction, separation and the like in the preparation method of the (4-chloro-1H-pyrazoline [3,4-d ] pyrimidin-3-yl) aryl ketone can be combined or separated at will, and the purpose of the invention can be achieved.
The room temperature is 15 ~ 30 ℃.
According to the preparation method of the (4-chloro-1H-pyrazoline [3,4-d ] pyrimidine-3-yl) aryl ketone, 3-bromo-4-chloro-1H-pyrazoline [3,4-d ] pyrimidine is used as a raw material, and is subjected to one-step condensation with an acyl chloride compound to obtain the target product compound (4-chloro-1H-pyrazoline [3,4-d ] pyrimidine-3-yl) aryl ketone (formula A), so that the reaction route is short, the side reactions are few, the product is easy to purify, and the yield of the whole synthesis route is improved; the method has the advantages of good repeatability of route steps, high conversion rate and yield, good universality, suitability for workshop operation amplification and wide application prospect, and can be applied to the preparation of (4-chloro-1H-pyrazoline [3,4-d ] pyrimidine-3-yl) aryl ketone with various substituent structures.
Detailed Description
The following describes preferred embodiments of the present invention to make the technical contents thereof clearer and easier to understand. The invention may be embodied in many different forms of embodiments, which are intended to be illustrative only, and the scope of the invention is not intended to be limited to the embodiments shown herein.
If there is an experimental method not specified specific conditions, it is usually carried out according to conventional conditions, such as the relevant instructions or manuals.
EXAMPLE 1 Synthesis of 4-chloro-1H-pyrazolin [3,4-d ] pyrimidin-3-yl) (o-tolyl) methanone
Stirring and cooling a tetrahydrofuran (20mL) solution of A-1(2.0g) to-78 ℃ under the protection of nitrogen, slowly dropwise adding n-butyllithium (8mL), stirring for 30 minutes, dropwise adding a tetrahydrofuran (10mL) solution of a compound A-2a (1.6g), maintaining the temperature of-78 ℃ for reaction and stirring for 30 minutes, naturally heating to room temperature, and continuing to stir for reaction for 2 hours; after the reaction is finished, adding water (50mL) into the reaction system for extraction and extinguishment, extracting with ethyl acetate, collecting organic phase saturated saline solution for washing, drying with anhydrous sodium sulfate, filtering, concentrating the filtrate to remove the solvent, and carrying out column chromatography separation and purification on residues to obtain a white solid target product compound (4-chloro-1H-pyrazoline [3,4-d ] pyrimidin-3-yl) (o-tolyl) methanone (formula A-a) (1.87g, yield 80%);
the compound a-a obtained above was subjected to structural NMR detection, and the detection results were as follows:
1H NMR(400MHz,CD3OD):δppm 8.91(s,1H),7.62-7.60(d,1H),7.47-7.43(t,1H),7.35-7.32(m,2H),2.51(s,3H);
the detection result shows that the synthesized compound A-a has correct structure.
EXAMPLE 2 Synthesis of (4-chloro-1H-pyrazolin [3,4-d ] pyrimidin-3-yl) (2-chloro-4-phenoxyphenyl) methanone
Stirring and cooling a tetrahydrofuran (20mL) solution of A-1(2.0g) to-78 ℃ under the protection of nitrogen, slowly dropwise adding n-butyllithium (8mL), stirring for 30 minutes, dropwise adding a tetrahydrofuran (15mL) solution of a compound A-2b (2.5g), maintaining the temperature of-78 ℃ for reaction, stirring for 60 minutes, naturally heating to room temperature, and continuously stirring and reacting for 3 hours; after the reaction is finished, adding water (50mL) into a reaction system, performing extraction and extinguishment, extracting with ethyl acetate, collecting organic phase saturated saline solution, washing, drying with anhydrous sodium sulfate, filtering, concentrating filtrate to remove a solvent, and performing column chromatography separation and purification on residues to obtain a white solid target product compound (4-chloro-1H-pyrazoline [3,4-d ] pyrimidin-3-yl) (2-chloro-4-phenoxyphenyl) methanone (formula A-b) (2.54g, yield 81%);
the compound a-b obtained above was subjected to structural NMR detection, and the detection results were as follows:
1H NMR(400MHz,CD3OD):δppm 8.92(s,1H),7.68-7.66(d,1H),7.48-7.44(m,2H),7.28-7.24(t,1H),7.12-6.99(m,4H);
the detection result shows that the synthesized compound A-b has correct structure.
The invention is not limited to the foregoing embodiments. The invention extends to any novel feature or any novel combination of features disclosed in this specification and any novel method or process steps or any novel combination of features disclosed.
Claims (6)
1. A preparation method of (4-chloro-1H-pyrazoline [3,4-d ] pyrimidine-3-yl) aryl ketone is characterized in that the structure of the (4-chloro-1H-pyrazoline [3,4-d ] pyrimidine-3-yl) aryl ketone is shown as the following formula A,
the preparation method of the (4-chloro-1H-pyrazoline [3,4-d ] pyrimidine-3-yl) aryl ketone has a route shown in the following scheme I:
route I:
wherein R, R' are each independently selected from hydrogen, halogen, C1-C10 alkyl, C5-C15 aryl, C1-C10 alkoxy, C5-C15 aryloxy;
the preparation method of the (4-chloro-1H-pyrazoline [3,4-d ] pyrimidine-3-yl) aryl ketone comprises the following specific operation steps: dissolving a compound A-1 in an oxygen-containing nonpolar solvent, cooling to-78 ℃ in an inert gas environment, adding an alkyl lithium reagent, stirring for 30-60 minutes, adding a compound A-2, keeping a reaction solution at-78 ℃ for reaction, stirring for 30-60 minutes, heating to room temperature, and continuing stirring for reaction for 2-3 hours; adding water into the reaction liquid for quenching, adding an organic solvent for extraction, washing an organic phase, drying, filtering, concentrating to remove the organic solvent, and purifying by column chromatography to obtain the target product (4-chloro-1H-pyrazoline [3,4-d ] pyrimidine-3-yl) aryl ketone compound.
2. The method of claim 1,
the halogen is fluorine, chlorine or bromine;
the alkyl is straight chain or branched chain or cyclic;
the aryl is C5-C15 aliphatic aryl and heterocyclic aryl containing 1-10 carbon atoms;
the alkyl, aryl, alkoxy, aryloxy groups are unsubstituted or substituted with one or more substituents selected from the group consisting of: halogen, hydroxyl, cyano, carbonyl, mercapto, alkylthio, acylamino, aliphatic hydrocarbon group, aryl.
3. The method of claim 1,
r, R' are each independently selected from hydrogen, fluoro, chloro, bromo, methyl, ethyl, propyl, isopropyl, cyclopropyl, butyl, isobutyl, cyclobutyl, cyclopentyl, cyclohexyl, phenyl, pyridinyl, pyrimidinyl, pyrrolyl, pyrazolyl, methoxy, ethoxy, phenoxy; wherein said methyl, ethyl, propyl, isopropyl, cyclopropyl, butyl, isobutyl, cyclobutyl, cyclopentyl, cyclohexyl, phenyl, pyridyl, pyrimidinyl, pyrrolyl, pyrazolyl, methoxy, ethoxy, phenoxy are unsubstituted or substituted by one or more substituents selected from the group consisting of: alkyl, halogen, aryl.
4. The method of claim 1, wherein R, R' are each independently selected from hydrogen, fluorine, chlorine, bromine, methyl, ethyl, propyl, isopropyl, methoxy, ethoxy, phenoxy.
5. The method of claim 1,
the oxygen-containing nonpolar solvent is tetrahydrofuran, dioxane, diethyl ether and methyl tert-butyl ether;
the alkyl lithium reagent is n-butyl lithium, isobutyl lithium, sec-butyl lithium and tert-butyl lithium;
the organic solvent is dichloromethane, ethyl acetate, diethyl ether and methyl tert-butyl ether.
6. The method of claim 1,
the molar ratio of the compound A-1 to the compound A-2 is 1: 1-1: 1.5;
the weight volume ratio of the compound A-1 to the oxygen-containing nonpolar solvent is 1: 10-1: 20;
the volume ratio of the compound A-1 to the lithium alkyl reagent is 1: 4-1: 8.
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WO2013069907A1 (en) * | 2011-11-08 | 2013-05-16 | 주식회사 엘지화학 | Adhesive composition for an antistatic protective film, and production method therefor |
CN103857396A (en) * | 2011-07-13 | 2014-06-11 | 药品循环公司 | Inhibitors of bruton's tyrosine kinase |
CN109952306A (en) * | 2016-04-19 | 2019-06-28 | 加利福尼亚大学董事会 | ErbB inhibitor and application thereof |
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CN103857396A (en) * | 2011-07-13 | 2014-06-11 | 药品循环公司 | Inhibitors of bruton's tyrosine kinase |
WO2013069907A1 (en) * | 2011-11-08 | 2013-05-16 | 주식회사 엘지화학 | Adhesive composition for an antistatic protective film, and production method therefor |
CN109952306A (en) * | 2016-04-19 | 2019-06-28 | 加利福尼亚大学董事会 | ErbB inhibitor and application thereof |
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