- Fenbendazole production process and production device
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The invention discloses a fenbendazole production process and a production device, the production process comprises a nitration reaction, a condensation reaction, a reduction reaction and a cyclization reaction, and finally the fenbendazole is obtained through centrifugation and drying. The production device comprises a plurality of reaction kettles, a distillation device and a distillation recovery device, the reaction kettles are respectively a nitration reaction kettle, a condensation reaction kettle, a cyclization reaction kettle and a reduction reaction kettle, and the nitration reactionkettle, the condensation reaction kettle, the cyclization reaction kettle, the distillation device and the reduction reaction kettle are sequentially communicated through feeding pipes. According to the process, the product purity can be improved; few types of chemical reagents are adopted, and methanol and methylbenzene are recycled so that reagent consumption is reduced, waste is avoided, and the process is economical and environmentally friendly; the process route is simple, the production period is shortened, and the production efficiency is improved; according to the production device, automatic feeding is achieved through the feeding mechanism, the automation degree is high, manual operation is reduced, and efficiency is improved.
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- Synthetic method of fenbendazole
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A synthetic method of fenbendazole belongs to the technical field of insect repellents, and specifically comprises the following steps: carrying out condensation reaction on 5-chloro-2-nitroaniline and a sodium thiophenol aqueous solution in a mixed solution of n-propyl alcohol and water to obtain 5-thiophenyl-2-nitroaniline; carrying out reduction reaction on the 5-thiophenyl-2-nitroaniline in a high-pressure kettle under the catalysis of raney nickel to generate 4-thiophenyl o-phenylenediamine; and mixing the 4-thiophenyl o-phenylenediamine and N-(trichloromethyl) methyl carbamate for a cyclization reaction to obtain fenbendazole; the method has the advantages that conditions are mild, operation is easy and convenient, ammonium chloride can be prevented from being generated in the cyclization process, and the three-waste cost is low; the generation of amine salt is avoided, and the treatment cost of three wastes is greatly reduced; and the yield of the fenbendazole can reach 84.27% to 89.99%, and the purity of the fenbendazole can reach 96.39% to 99.71%.
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Paragraph 0020-0034
(2021/08/14)
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- Preparation method of 2-amino-5-phenylthio-(2-methoxy)acetanilide
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The invention belongs to the technical field of organic synthesis and particularly relates to a preparation method of 2-amino-5-phenylthio-(2-methoxy)acetanilide. According to the method, 2-nitro-5-(phenylthio)aniline is prepared from 2-nitro-5-mercaptoaniline and benzene halide and then subjected to a reaction with methyl methoxyacetate, 2-nitro-5-phenylthio-(2-methoxy)acetanilide is generated and subjected to catalytic hydrogenation reduction finally, and the target product is obtained. The preparation method has good reaction selectivity, and the obtained target product is high in purity and yield; use of high-toxicity materials is avoided, requirements for equipment and operation conditions are reduced, and safety and stability of the preparation method are improved; doses of the reaction materials are optimized, and excess benzene halide and methyl methoxyacetate can be recycled after being recovered simply; little solid waste is produced, waste treatment cost is reduced greatly,and the requirement for environmental protection is met.
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Paragraph 0040-0041; 0052-0053
(2020/08/12)
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- A preparation method of curing melanotumor
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The invention discloses a preparation method of fenbendazole and provides a brand-new synthesis route of the fenbendazole. The fenbendazole is prepared from m-dichlorobenzene as a starting material through the steps of nitrification, condensation, amination, reduction and cyclization. The preparation method is characterized in that the starting material m-chloroaniline in the existing industrial route is changed to the cheap m-dichlorobenzene; the existing reduction technology with sodium sulfide dihydrate is changed to the clean and high-efficiency reduction technology; and the new synthesis technology is concise and simple, high in efficiency, slight in pollution, high in quality, and suitable to industrial production.
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- Efficient Synthesis in Three Steps and Spectral Determination of Methyl-5-[(o-, m-, and p-substituted-phenylthio]-2-Benzimidazolecarbamates
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The preparation and spectral properties of ten novel methyl 5-[(o-, m-, and p-substituted)-phenylthio]-2-benzimidazolecarbamates with possible pharmacological activity as antihelmintics is described; by condensation and cyclization between 5-methylthioures sulfate chloroformic acid methyl ester and 3,4-diaminophenyl-substituted-phenylthio ether dissolved in ethanol. The structures of all final products were corroborated by ir; 1H-nmr, 13C-nmr and ms.
- Cortes, Eduardo Cortes,Mendoza, Rafael Sosa,Gutierrez, Maximiliano Santibanez,De Cortes, Olivia Garcia-Mellado
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p. 273 - 276
(2007/10/03)
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- Method for preparing 2-nitro-5-(phenylthio)-anilines
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The invention relates to a process for preparing 2-nitro-5-(phenylthio)anilines of formula (I) wherein R1represents hydrogen, C1-C8-alkyl, C3-C8-cycloalkyl, C1-C8-alkoxy, or halogen and R2represents hydrogen, C1-C8-alkyl, C3-C8-cycloalkyl, C1-C8-alkoxy, halogen, or C6-C10-aryl optionally substituted with C1-C8-alkyl, C1-C8-alkoxy, or halogen, by reacting, in a solvent, a 5-chloro-2-nitroaniline of the formula (II) wherein R1is as defined for formula (I), with a thiophenol of the formula (III) wherein R2is as defined for formula (I), and ammonia.
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- Use of compounds for the elevation of pyruvate dehydrogenase activity
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The use of compounds of the formula (I), and salts thereof; and pharmaceutically acceptable in vivo cleavable prodrugs of said compound of formula (I); and pharmaceutically acceptable salts of said compound or said prodrugs: wherein: Ring C is phenyl or a carbon linked heteroaryl ring substituted as defmed within; R1is an ortho substituent as defined within; n is 1 or 2; A—B is a linking group as defined within; R2and R3are as defined within; R4is hydroxy, hydrogen, halo, amino or methyl; in the manufacture of a medicament for use in the elevation of PDH activity in warm-blooded animals such as humans is described. Pharmaceutical compositions, methods and processes for preparation of compounds of formula (I) are also described.
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- 5(6)-Benzene ring substituted benzimidazole-2-carbamate derivatives having anthelmintic activity
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Carbalkoxythioureidobenzene derivatives represented by the following formula: STR1 where R is a lower alkyl group having 1 to 4 carbon atoms; R1 is --SR2, --SOR2, --SO2 R2, --OR2, --SCN, --SC(O)NR3 R4, or --M'(CH2)n MR7 where n is 1-4; R2 is lower alkyl having 1 to 6 carbon atoms, cycloalkyl having 3 to 7 carbon atoms, lower alkenyl or lower alkynyl having 3 to 6 carbon atoms, aralkyl or aryl, provided that when R1 is --SO2 R2, R2 is not aralkyl or phenyl; R3 and R4 are independently hydrogen or lower alkyl having 1 to 6 carbon atoms; Y is amino, nitro, acylamino where the acyl portion has 1 to 6 carbon atoms, --NHC(O) (CH2)m COOH where m is 1-6, or --NHC(S)NHCOOR; M and M' are independently O, S or STR2 and R7 is lower alkyl having 1 to 4 carbon atoms or aryl. The R1 substitution is either at the 4- or 5-position. The compounds are useful as pesticides, particularly as anthelmintic and antifungal agents.
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- Substituted (alkoxycarbonylthioureido)-(acylamino)-benzene derivatives
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Benzene derivatives of the formula: STR1 wherein R1 represents alkyl, R2 represents a group --SR3, --SOR3, --SO2 R3, --OR3, --SCONH2, --SCN or --T(CH2)m T1 R4 [wherein R3 represeents alkyl, cycloalkyl, alkenyl, alkynyl, aralkyl, unsubstituted or substituted aryl, or cycloalkylalkyl, R4 represents hydrogen or alkyl, T and T1 each represent oxygen, sulphur or sulphinyl, and m is an integer from 1 to 7] whose position on the benzene ring is either para to the group --NHCSNHCOOR1 or para to the group --NHCOAZ, A represents a bivalent straight-chain aliphatic hydrocarbon radical of 1 to 4 carbon atoms or a said hydrocarbon radical substituted by at least one methyl group, and Z represents a group of the formula:- STR2 wherein R5 represents hydrogen or alkyl, R6 represents hydrogen, alkyl or phenylalkyl, and R7 represents hydrogen or alkyl, or R6 and R7 together with the nitrogen atom to which they are attached form a 5-,6- or 7-membered heterocyclic ring optionally substituted by alkyl group(s), and X- represents a pharmaceutically acceptable anion, are new compounds useful as anthelmintics and antifungal agents.
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- 7(8)-Substituted triazinobenzimidazoles and anthelmintic compositions and method
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7(8)-substituted triazinobenzimidazoles represented by the formula: STR1 where R is a lower alkyl group having 1 to 4 carbon atoms; R' is diloweralkylaminoalkyl (C2-6) or alkyl having 1 to 18 carbon atoms; R2 is phenylsulfinyl, phenoxyethoxy, benzyloxyethoxy, methoxyethylsulfinyl, or 3-chloroprop-1-ylsulfinyl; the R2 -substitution being at the 7(8)-position; or a pharmaceutically acceptable salt thereof. The compounds are useful as pesticides, particularly as antifungal and anthelmintic agents.
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- 5(6)-Benzene ring substituted benzimidazole-2-carbamate derivatives having anthelmintic activity
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Benzene ring substituted benzimidazole-2-carbamate derivatives represented by the formula: SPC1 Where R is a lower alkyl group having 1 to 4 carbon atoms; R1 is --SR5 or --OR5 ; and R5 is aryl. The R1 substitution is at the 5(6)-position. The compounds are useful as pesticides, particularly as anthelmintic and antifungal agents.
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- Anthelmintically active 2-carbalkoxy-amino-benzimidazole-5(6)-phenyl ethers
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2-Carbalkoxy-amino-benzimidazole-5(6)-phenyl ethers of the formula (I) SPC1 in which R1 represents alkyl of 1 to 4 carbon atoms, R2 and R3 represent, independently of each other, hydrogen, hydroxyl, alkoxy of 1 to 4 carbon atoms, halogen, trifluoromethyl, alkyl of 1 to 4 carbon atoms or carbalkoxy of 1 to 4 carbon atoms in the alkoxy group, R4 represents hydrogen or chlorine and X represents oxygen or sulfur, useful as anthelmintics.
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