- Preparation method of high-purity pirfenidone
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The invention relates to the technical field of drug synthesis, and discloses a preparation method of high-purity pirfenidone. The preparation method at least comprises the following steps: (1) uniformly mixing 2-amino-5-methylpyridine, a diazotization reagent and water, cooling to a temperature of -4 DEG C to 3 DEG C, adding an acid solution, and carrying out a thermal insulation reaction; heating for hydrolysis after the reaction is completed, cooling, then adjusting the pH value to 6.5-7.5 by using a sodium hydroxide solution with the mass fraction of 30%, extracting an organic phase by using a first solvent, drying, and concentrating under reduced pressure to obtain a 2-hydroxy 5-methylpyridine crude product; (2) adding a second solvent into the 2-hydroxy 5-methylpyridine crude productfor recrystallization to obtain a 2-hydroxy 5-methylpyridine pure product; (3) uniformly mixing the 2-hydroxy 5-methylpyridine pure product, iodobenzene, a catalyst and anhydrous potassium carbonate,heating and reacting, carrying out suction filtration, and carrying out vacuum concentration to obtain a pirfenidone crude product; and (4) adding a third solvent into the pirfenidone crude product,heating to dissolve, cooling to -5 to 5 DEG C, crystallizing for 1 to 1.5 hours, carrying out suction filtration, and drying to obtain a pirfenidone pure product.
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Paragraph 0062-0242
(2020/05/02)
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- Method for preparing anti-fibrotic drug
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The invention relates to a method for preparing an anti-fibrotic drug. The method for preparing pirfenidone is characterized by comprising the following steps of: hydrolyzing a starting material 2-amino-5-methylpyridine by adopting a reverse diazotization hydrolysis method, extracting by using an extraction solvent and recrystallizing by using a recrystallization solvent to obtain 2-hydroxy-5-methylpyridine; in the presence of anhydrous potassium carbonate and active copper, mixing with iodobenzene and heating to carry out nucleophilic substitution reaction to produce a target compound: pirfenidone crude product; and sequentially carrying out recrystallization and purification by using a recrystallization solvent: ethyl acetate and absolute ethanol to finally obtain a pirfenidone pure product. The method disclosed by the invention has the following characteristics that: the initial raw material: the 2-amino-5-methylpyridine is a commercially available chemical product which is cheap and easy to obtain; the reverse diazotization is adopted to replace conventional diazotization reaction and the operation is simple and convenient; the purification methods of the 2-hydroxy-5-methylpyridine and the final product pirfenidone are easy to operate and high in yield; and the processing method is low in energy consumption and the production cost is reduced.
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Paragraph 0016; 0018
(2019/04/27)
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- 5-alkyl-N-substituted aryl pyridone derivative, preparation method thereof and application of derivative
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The invention provides a compound as shown in a formula I, or pharmacologically acceptable salt of the compound, or a prodrug of the compound, or a hydrate or solvate of the compound or a crystal form of the compound. The invention further provides a preparation method and an application of the compound. The structurally novel 5-methyl-2(1H) pyridone derivative as shown in the formula I has an obvious inhibiting effect on fibroblast proliferation and fibroblast secretory fiber binding protein (Fn), and the inhibiting effect is more significant than that of a positive drug pirfenidone (PF). The compound has an excellent application prospect in preparation of drugs for treating or preventing diseases such as fibrosis diseases and tumors.
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Paragraph 0082; 0085-0087; 0100-0101
(2019/10/04)
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- A process for preparing 2 - chloro -5 - methyl pyridine method (by machine translation)
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The invention belongs to the technical field of organic chemical industry, relates to 2 - chloro - 5 - methyl pyridine preparation method, more specifically, relates to a 5 - methyl - 3, 4 - dihydro pyridine - 2 (1 H) - one (hereinafter referred to as the: pyridone) and chlorine gas, first synthesis of 2 - hydroxy - 5 - methyl pyridine (hereinafter referred to as: synthetic azo), re-chlorinated preparing 2 - chloro - 5 - methyl pyridine. (by machine translation)
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Paragraph 0012; 0017-0019; 0025; 0028; 0032; 0036
(2019/07/04)
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- THE DERIVATIVES OF PYRIDONE AND THE USE OF THEM
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The present invention provides N-substituted-2(1H) pyridones or the pharmaceutical acceptable salts thereof, and the pharmaceutical preparations containing the compounds. The compounds of the present invention can be used to treat various fibrotic diseases effectively, e.g., hepatic fibrosis.
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Page/Page column 7
(2008/06/13)
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- (Methylsulfonyl)phenyl-2-(5H)-furanones as COX-2 inhibitors
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The invention encompasses the novel compound of Formula I useful in the treatment of cyclooxygenase-2 mediated diseases. STR1 The invention also encompasses certain pharmaceutical compositions for treatment of cyclooxygenase-2 mediated diseases comprising compounds of Formula I.
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- (Methylsulfonyl)phenyl-2-(5H)-furanones as COX-2 inhibitors
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The invention encompasses the novel compound of Formula A that is useful in the treatment of cyclooxygenase-2 mediated diseases. STR1 The invention also encompasses certain pharmaceutical compositions for treatment of cyclooxygenase-2 mediated diseases comprising compounds of Formula A.
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- 3,4-diaryl-2-hydroxy-2,5-dihydrofurans as prodrugs to COX-2 inhibitors
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The invention encompasses the novel compound of Formula I useful in the treatment of cyclooxygenase-2 mediated diseases. STR1 The invention also encompasses certain pharmaceutical compositions for treatment of cyclooxygenase-2 mediated diseases comprising compounds of Formula I.
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- Azetidinone compounds useful in the preparation of carbapenem antibiotics and process for preparing carbapenem and penem compounds
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Compounds of formula (I): STR1 wherein: R1 is hydrogen or a hydroxy-protecting group; R2 is alkyl, alkoxy, halogen, optionally substituted phenyl or optionally substituted phenoxy; R3 is optionally substituted pyridyl, optionally substituted quinolyl or phenyl group which has a substituent of formula --CYNR5 R6, where Y is oxygen or sulfur, and R5 and R6 are each alkyl, aryl or aralkyl, or R5 and R6 and the nitrogen to which they are attached together form a heterocyclic group; is R4 hydrogen or an amino-protecting group; and Z is sulfur or oxygen; are valuable intermediates in the preparation of carbapenem compounds and retain a desirable configuration during conversion to such carbapenem compounds. Penem and carbapenem compounds having a group of formula --SA' are prepared from a corresponding compound having a substituted thio, sulfinyl or sulfonyl group at this position by reaction with a compound A'SH (where A' is an organic group) in the presence of a salt of a metal of Group II or III of the Periodic Table.
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- Process for the preparation of 2-substituted 5-alkyl-pyridines
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The title compounds of the formula STR1 can be prepared by cyclization of aminomethylenated 2-pentenoic acid derivatives of the formula STR2 where R, X, R1, R2 and Z have the meaning given in the description, in the presence of acids or ammonia. Preferably, aminomethylenated pentenoic acid derivatives are employed which can be prepared from pentenoic acid derivatives of the formula or with ortho-amides of the formula STR3 The meanings of A and B are also given in the description.
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- NITROGEN-CONTAINING SPIROCYCLES
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Spirocycles of general structural formula: STR1 are Class III antiarrhythmic agents.
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- Synthesis of 2-substituted-5-methylpyridines from methylcyclobutanecarbonitrile, valeronitrile and pentenonitrile intermediates
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3-Methyl-2-alkylamino-1-halo-1-cyano cyclobutanes are cleaved under acid conditions to form 2-halo-4-formylvaleronitrile and 4-formyl-2-pentenonitrile which can be cyclized to form 2-substituted-5-methylpyridine derivatives. These pyridine derivatives are useful as starting materials in the manufacture of herbicides such as fluazifop-butyl.
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