66608-52-4Relevant academic research and scientific papers
Albendazole synthesis method
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, (2019/03/25)
The invention discloses an albendazole synthesis method. The albendazole synthesis method includes reacting ammonium thiocyanate with chlorine gas in a lower alcohol solvent to obtain chlorothiocyanate, reacting ortho-nitroaniline with the chlorothiocyanate in the lower alcohol solvent to obtain 4-thiocyano-2-nitroaniline, reacting the 4-thiocyano-2-nitroaniline with a sodium hydroxide solution toobtain 4-sodium sulfonate-2-nitroaniline, performing hydrochloric acid acidification to obtain 4-mercapto-2-nitroaniline, subjecting the 4-mercapto-2-nitroaniline and propylene to Markovnikov addition reaction to obtain 4-propylthio-2-nitroaniline, and reacting 4-propylthio-o-phenylenediamine with methylcyanocarbamate to obtain albendazole. The albendazole synthesis method has the advantages thata novel synthetic route is applied to prepare the albendazole, the defects of high impurity quantity and low yield in the current production process are overcome, the chlorothiocyanate is prepared toserve as an intermediate and then reacts with the ortho-nitroaniline, and impurities can be avoided effectively; the propylene is introduced for the addition reaction, raw materials are clean and free from pollution, introduction of highly toxic sodium cyanide is avoided, the total yield is high, and the albendazole synthesis method has a good industrialization prospect.
Novel preparation method of albendazole
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Paragraph 0047; 0050-0051; 0059; 0062-0063, (2019/01/05)
The invention provides a novel preparation method of albendazole. According to the invention, a novel synthetic route of albendazole is provided, wherein 2-nitro-5-chloroaniline is used as a startingmaterial and is subjected to reactions of substitution, condensation, reduction and cyclization to obtain high-purity albendazole. The method is characterized in that: the 2-nitro-5-chloroaniline is subjected to substituted reaction, and is subjected to condensation reaction with halogenated n-propane to obtain 2-nitro-5-albendazole aniline, which avoids the use of propanethiol with a high price and a stimulating odor. The use of a high-risk hydrogenation reduction process is avoided, a vulcanization alkali reduction process which is cheap and easily available in raw materials is used, a set of non-toxic treatment schemes for reducing layered waste water are provided, and meanwhile, secondary sodium thiosulfate can be obtained and the waste is turned into wealth. According to the method, the yield is high, the safety risk is low, the industrial production is facilitated, the content of the prepared albendazole is high, the content of single impurities is small, and the latest standardssuch as the US Pharmacopeia and the European Pharmacopoeia are met.
4 - c sulfur preparation process of the manufacture of phenylenediamine
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Paragraph 0017; 0021; 0022; 0023; 0024; 0025; 0026-0028, (2017/08/19)
The invention relates to a process for preparing 4-propylthio-o-phenylenediamine. According to the process provided by the invention, 4-propylthio-o-phenylenediamine is prepared from 2-nitro-4-propylthio phenylamine through being reduced by nickel aluminum alloy and an aqueous solution of ammonium chloride under the condition of heating. The process is high in yield, simple in operation and simple and convenient in after-treatment and has a relatively good application prospect.
A preparing method of albendazole
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, (2016/10/31)
A preparing method of albendazole is disclosed. The method adopts 2-nitro-4-thiocyanatoaniline as a raw material, and includes salifying with an aqueous sodium hydroxide solution in an n-propanol solvent under nitrogen protection, reacting with bromopropane, and separating to obtain an n-propanol solution of 2-nitro-4-(propylthio)aniline, and therefore a problem that an impurity that is methyl 5-(methylthio)benzoimidazol-2-yl carbamate in products is high in content because steps of salifying in methanol with sodium sulfide and then reacting with bromopropane in processes at present is overcome. A technique of reducing the 2-nitro-4-(propylthio)aniline by utilizing hydrazine hydrate is adopted to replace a technique of reducing with sodium sulfide at present, thus overcoming a problem that sulfur-containing waste water is high in amount and difficult to treat in the sodium sulfide reduction technique. A methanol solution of methyl O-methyl isourea formate is adopted as a ring closing agent, thus overcoming a problem that waste water is high in amount in processes at present when cyanamide and an aqueous methyl formate solution are adopted as ring closing agents. The method is advantaged by a small waste water amount, capability of being environmental friendly, high product purity, and the like.
Catalytic hydrogenation of sulfur-containing nitrobenzene over Pd/C catalysts: In situ sulfidation of Pd/C for the preparation of PdxSy catalysts
Zhang, Qunfeng,Xu, Wei,Li, Xiaonian,Jiang, Dahao,Xiang, Yizhi,Wang, Jianguo,Cen, Jie,Romano, Stephen,Ni, Jun
, p. 17 - 21 (2015/09/28)
The preparation of supported palladium sulfides catalysts has attracted much attention due to their good sulfur-resistant properties in the hydrogenation of sulfur-containing compounds. In this work, we unambiguously demonstrated that Pd/C catalyst could be in situ sulfided by organic sulfur-containing reactant molecules and the sulfidation was highly dependent on temperature. The in situ sulfidation of Pd/C catalyst was composed of a reaction of Pd with the sulfur derived from the cleavage of C-S bond of sulfur-containing reactant molecules, followed by a transformation to PdxSy at high temperatures (around 120 °C). The sulfided Pd/C catalyst could be used for at least 18 recycles without a significant loss in its activity during the hydrogenation of sulfur-containing nitrobenzene at 180 °C with 3 MPa H2, which could be attributed to the stable presence of Pd4S and Pd16S7.
PROCESS FOR PREPARATION OF ALBENDAZOLE
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, (2013/11/19)
The present invention discloses a novel, cost-effective process for preparation of a benzimidazole carbamates compound. Specifically, it relates to the process for the preparation of anti-parasite bulk drug albendazole. The process comprises a) thiocyanating 2-nitroaniline of formula VI with ammonium thiocyanated in presence of a halogen to obtain 2-nitro-4-thiocyanoaniline of formula V; b)propylating 2-nitro-4-thiocyanoaniline of formula V with propylbromide in presence of n-propanol and a base in absence of a phase transfer catalyst to obtain 4-propylthio-2-nitroaniline of formula III; C) reducing the nitro group of 4-propylthio-2-nitroaniline prepared in step b) by reacting an aqueous alkali metal sulphide or an alkaline metal sulphide to obtain 4-propylthio-o-phenylenediamine of formula II; and d)condensing 4-propylthio-o-phenylenediamine of formula II with alkali or alkaline earth metal salt of methylcyano carbamate in presence of an acid to form Albendazole of formula I.
A PROCESS FOR PREPARATION OF ALBENDAZOLE
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, (2012/06/15)
The present invention discloses a novel, cost-effective process for preparation of a benzimidazole carbamates compound. Specifically, it relates to the process for the preparation of anti-parasite bulk drug albendazole. The process comprises a) thiocyanating 2-nitroaniline of formula VI with ammonium thiocyanated in presence of a halogen to obtain 2-nitro-4-thiocyanoaniline of formula V; b)propylating 2-nitro-4-thiocyanoaniline of formula V with propylbromide in presence of n-propanol and a base in absence of a phase transfer catalyst to obtain 4-propylthio-2-nitroaniline of formula III; C) reducing the nitro group of 4- propylthio-2-nitroaniline prepared in step b) by reacting an aqueous alkali metal sulphide or an alkaline metal sulphide to obtain 4-propylthio-o-phenylenediamine of formula II; and d)condensing 4-propylthio-o-phenylenediamine of formula II with alkali or alkaline earth metal salt of methylcyano carbamate in presence of an acid to form Albendazole of formula I.
Design, synthesis and identification of novel benzimidazole derivatives as highly potent NPY Y5 receptor antagonists with attractive in vitro ADME profiles
Tamura, Yuusuke,Omori, Naoki,Kouyama, Naoki,Nishiura, Yuji,Hayashi, Kyouhei,Watanabe, Kana,Tanaka, Yukari,Chiba, Takeshi,Yukioka, Hideo,Sato, Hiroki,Okuno, Takayuki
scheme or table, p. 5498 - 5502 (2012/09/22)
Optimization of our HTS hit 1, mainly focused on modification at the C-2 position of the benzimidazole core, is described. Elimination of the flexible and metabolically labile -S-CH2- part and utilization of less lipophilic pyridone substructur
Synthesis and antiparasitic activity of Albendazole and Mebendazole analogues
Navarrete-Vazquez, Gabriel,Yepez, Lilian,Hernandez-Campos, Alicia,Tapia, Amparo,Hernandez-Luis, Francisco,Cedillo, Roberto,Gonzalez, Jose,Martinez-Fernandez, Antonio,Martinez-Grueiro, Mercedes,Castillo, Rafael
, p. 4615 - 4622 (2007/10/03)
Albendazole (Abz) and Mebendazole (Mbz) analogues have been synthesized and in vitro tested against the protozoa Giardia lamblia, Trichomonas vaginalis and the helminths Trichinella spiralis and Caenorhabditis elegans. Results indicate that compounds 4a, 4b (Abz analogues), 12b and 20 (Mbz analogues) are as active as antiprotozoal agents as Metronidazole against G. lamblia. Compound 9 was 58 times more active than Abz against T. vaginalis. Compounds 8 and 4a also shown high activity against this protozoan. Compounds 4b and 5a were as active as Abz. None of the Mbz analogues showed activity against T. vaginalis. The anthelmintic activity presented by these compounds was poor.
Concerning the baker's yeast (Saccharomyces cerevisiae) mediated reduction of nitroarenes and other N-O containing functional groups
Blackie, Josie A.,Turner, Nicholas J.,Wells, Andrew S.
, p. 3043 - 3046 (2007/10/03)
Nitro- and nitrosoarenes can be reduced using baker's yeast (Saccharomyces cerevisiae) under two distinct sets of conditions, one of which is in fact a well established non-enzymic process. In order to clarify reports in the literature a comparison of the two methods has been made.
