- Preparation method of nifuratel intermediate
-
The invention provides a preparation method of a nifuratel intermediate. The preparation method comprises the following steps: (1) reacting sodium methyl mercaptide with epoxy chloropropane to prepare 2-(methylthio methyl)-oxetane; (2) dropwise adding 2-(methylthio methyl)-oxetane into hydrazine hydrate to prepare 3-methylthio-2-hydroxy-propyl hydrazine; (3) adding diethyl carbonate into 3-methylthio-2-hydroxy-propyl hydrazine to prepare a nifuratel intermediate, namely N-amino-5-methylthio methyl-2-oxazolidinone; and (4) salifying the prepared N-amino-5-methylthio methyl-2-oxazolidinone and concentrated hydrochloric acid to prepare the nifuratel intermediate hydrochloride. According to the preparation method of the nifuratel intermediate, disclosed by the invention, the nifuratel intermediate can be conveniently and quickly obtained, and the obtained nifuratel intermediate is high in yield, high in purity and stable in quality.
- -
-
Paragraph 0029-0031; 0038-0040; 0048-0050; 0057-0059; 0066
(2021/05/01)
-
- Industrial preparation method of nifuratel
-
The invention provides a preparation method of nifuratel. The preparation method comprises the following steps: (1) reacting sodium methyl mercaptide with epoxy chloropropane to prepare 2-(methylthiomethyl)-oxetane; (2) dropwise adding the 2-(methylthiomethyl)-oxygen heterocyclic propane into hydrazine hydrate, so as to prepare 3-methylthio-2-hydroxyl-propyl hydrazine; (3) adding diethyl carbonate into the 3-(methylthio-2-hydroxy)-propyl hydrazine, so as to prepare N-amino-5-(methylthiomethyl)-2-oxazolidinone; and (4) hydrolyzing the 5-nitrofuran formaldehyde diacetate in the presence of dilute acid to obtain a 5-nitrofurfural solution; under a dark condition, adding the prepared N-amino-5-methylthiomethyl-2-oxazolidinone into a 5-nitrofurfural solution, reacting at room temperature to obtain a nifuratel crude product, and recrystallizing and purifying to obtain a nifuratel pure product.
- -
-
Paragraph 0031-0084
(2021/05/05)
-
- Preparation process of anti-infective drug nifuratel
-
The invention belongs to the technical field of drug synthesis and in particular relates to a preparation process of an anti-infective drug nifuratel. The preparation process comprises the following steps: taking iodomethane, sodium sulfide and chlorocyclopropane as initial raw materials to obtain epoxy propyl methyl sulfide, carrying out ring-opening reaction with hydrazine hydrate to obtain 3-methylmercapto-2-hydroxyl-propylhydrazine, carrying out a ring-closure reaction to obtain N-amino-5-methylthiomethyl-2-oxazolidinone, hydrolyzing 5-nitro furfural diacetate in the presence of trifluoroacetic acid to obtain 5-nitro-2-furancarboxaldehyde, and performing condensation with N-amino-5-methylthiomethyl-2-oxazolidinone, thereby obtaining the nifuratel. Safe and cheap reagents are selected in the process route, and environment hazards are reduced. Meanwhile, the operating difficulty and reaction after-treatment burdens are reduced, the production safety is ensured, the process is a simple, green and economic process route for preparing the nifuratel, and the obtained product is high in yield, excellent in purity and suitable for large-scale industrial production of the nifuratel.
- -
-
Paragraph 0024; 0051-0056
(2018/05/16)
-
- A synthetic method of Nifuratel (by machine translation)
-
The invention discloses a method for synthesizing Nifuratel. The method of the invention is sodium methyl mercaptan, ech in catalyst-tetrabutyl ammonium bromide under the effect of the compound into a sulfur [...] propane, resulting a sulfur [...] propane and hydrazine reflux 1 - 3 hours to be hydrazinolysis, to obtain 3 - methylthio - 2 - hydroxy [...]; and the resulting reaction mixture in sodium methoxide under the action of the cyclization, shall be N - amino - 5 - methylthio methyl - 2 - oxazolidone, the resulting product with the 5 - nitro furfural b ethyl ester in dilute mineral acid conditions condensation, get the yellow powder 5 - [(methylthio) methyl] - 3 - [[ (5 - nitro - 2 - furyl methylene] amino] - 2 - oxazolidone. This invention lies in the use of its primary product with the raw material of the nature of the nature of the difference between the direct chemical combination, without rectification and purification, overcomes the tedious operation in production steps, simplifies the synthesis method, convenient for large-scale industrial production. (by machine translation)
- -
-
Paragraph 0022; 0024; 0025
(2018/11/22)
-
- Nifuratel method for the preparation of
-
The invention relates to a method for preparing nifuratel. The method comprises the steps of (1) synthesizing 2-(methylmercapto-methyl)-oxacyclopropane through epoxy chloropropane and sodium methyl mercaptide; (2) generating reaction between hydrazine hydrate and the 2-(methylmercapto-methyl)-oxacyclopropane to synthesize 3-methylmercapto-2-hydroxy-propyl hydrazine; (3) generating reaction between diethyl carbonate and 3-methylmercapto-2-hydroxy-propyl hydrazine to prepare N-amino-5-methylmercapto-methyl-2-oxazolidinone; (4) hydrolyzing 5-nitrofuran formaldehyde diacetate ester under an acidic condition to prepare 5-nitro-2-furaldehyde; (5) generating reaction between the 5-nitro-2-furaldehyde and the N-amino-5-methylmercapto-methyl-2-oxazolidinone obtained in the step (3) to obtain the nifuratel, wherein in the step (1), 15-crown ether-5 is used as a catalyst, so that the conversion rate is high; no organic solvent is used during posttreatment of a product, and the posttreatment is simple.
- -
-
Paragraph 0045; 0046
(2016/12/01)
-
- Protonation, and reductive cleavage by lithium of the C-S bond, in (methylthio)pentadienylic anions generated from various cis, trans-isomers of 1-(methylthio)-1,3-pentadiene and 1-(methylthio)-1,4-pentadiene
-
Treatment of the various cis,trans-isomers of CH3S-CH=CH-CH=CH-CH3 and CH3SCH=CH-CH2CH=CH2 with a slight excess of potassium amide in liquid ammonia, followed by quenching of the solutions thus obtained with ammonium chloride, gives, in all cases, the isomer CH3S-CH2-CH=CH-CH=CH2 (>= 90percent trans).From the anionic solutions 1H NMR spectra have been recorded.Reductive cleavage of the C-S bond of the anions CH3S-CH=CH-CH=CH-CH21- with lithium in liquid ammonia, followed by methylation, leads to almost complete recovery of CH3S-CH=CH-CH=CH-CH3.During this cleavage, the double bond next to sulfur retains its configuration, while the configu ration of the other double bond changes from trans to cis.It remains the same, however, on starting from a (methylthio)pentadiene with a cis-C3-C4 double bond.The ultimate result of the cleavage procedure with CH3S-CH=CH-CH2CH=CH2 is CH3S-CH=CH-CH=CH-CH3: the configuration of the C1-C2 double bond remains the same and the C3-C4 double bond is always cis.
- Graefing, R.,George, A.V.E.,Brandsma, L.
-
p. 346 - 351
(2007/10/02)
-