- Synthesis of 3,4-diaminobenzenethiol and its application in gold nanoparticle-based colorimetric determination of copper ions
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An improved synthetic method for the synthesis of 3,4-diaminobenzenethiol is presented. The practical application of this reagent as a new ligand for gold nanoparticles for the rapid detection of Cu2+ in water is demonstrated. The method is shown to have high sensitivity and selectivity. Well-defined peaks, proportional to the concentration of the corresponding Cu2+, were observed from 0.5 μM to 2 μM, and the recovery was in the range of 92-109%. This method provides a facile route for Cu2+ analysis.
- Zhang, Chi,Lu, Li-Qiang,Deng, Pan,Tian, Xi-Ke,Liu, Ming-Yang,Li, Ai-Min
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p. 105119 - 105124
(2016)
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Read Online
- Preparation method of fenbendazole intermediate 2-nitro-4-phenylthioaniline
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The invention relates to the technical field of veterinary drugs, and in particular, relates to a preparation method of fenbendazole intermediate 2-nitro-4-phenylthioaniline. The preparation method comprises the following steps: by taking o-nitroaniline and ammonium thiocyanate as raw materials and an organic solvent as a solvent of a reaction system, uniformly stirring and mixing, introducing chlorine, and filtering after the reaction of the raw materials is finished, so as to obtain 4-thiocyano-2-nitroaniline; taking 4-thiocyano-2-nitroaniline, adding sodium hydroxide and a reaction solvent,stirring and mixing, and filtering after the reaction is finished to obtain a sodium 4-amino-3-nitrothiophenol solution; carrying out a reaction on the sodium 4-amino-3-nitrothiophenol solution withbromobenzene under an alkaline condition, and after the reaction is finished, extracting to obtain the 2-nitro-4-phenylthioaniline. The preparation method is simple in process, the production cost isreduced, the production potential safety hazard can be reduced, the product yield is relatively high, and the environmental pollution is reduced.
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Paragraph 0020; 0030-0031; 0034-0035; 0038-0039; 0042-0043
(2020/07/14)
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- Albendazole synthesis method
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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.
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Paragraph 0047-0052
(2019/03/25)
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- Ratiometric SERS imaging and selective biosensing of nitric oxide in live cells based on trisoctahedral gold nanostructures
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Herein, a ratiometric SERS probe was created for monitoring nitric oxide (NO) by designing a novel molecule, 3,4-diaminobenzene-thiol, and immobilizing this molecule onto trisoctahedral gold nanostructures with superior SERS capability. The established probe possessed good selectivity and biocompatibility, high sensitivity and accuracy, thus enabling imaging and biosensing of NO in live cells.
- Xu, Qiao,Liu, Wei,Li, Li,Zhou, Feng,Zhou, Jian,Tian, Yang
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supporting information
p. 1880 - 1883
(2017/02/10)
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- PROCESS FOR PREPARATION OF ALBENDAZOLE
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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.
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Paragraph 0019
(2013/11/19)
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- A PROCESS FOR PREPARATION OF ALBENDAZOLE
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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.
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Page/Page column 5
(2012/06/15)
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- Preparation of N-methoxycarbonyl-N'-[2-nitro-4(5)-propyl-thiophenyl]thiourea as prodrugs of albendazole
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N-methoxycarbonyl-N'-(2-nitro-4-propylthiophenyl)thiourea and N-methoxycarbonyl-N'-(2-nitro-5-propylthiophenyl)thiourea, prodrugs of albendazole, have been synthesized. The biotransformation in rats, after oral administration of these prodrugs to albendazole and albendazole sulphoxide, is described.
- Hernandez-Luis, Francisco,Castillo, Rafael,Yepez-Mulia, Lilian,Cedillo-Rivera, Roberto,Martinez-Vazquez, Gabriel,Morales-Hurtado, Raul,Jung, Helgi,Sanchez, Monica,Hernandez-Campos, Alicia,Viveros, Noemi,Munoz, Onofre
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p. 2231 - 2236
(2007/10/03)
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- Process for the preparation of 2-benzimidazole carbamates
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A process for preparing 2-benzimidazole carbamate compounds by condensing an alkyl cyano carbamate with an o-phenylenediamine produced by reacting an ortho-nitro-aniline with thiocyanogen followed by replacement of the cyanide with an alkyl group and then converting the nitro group to the amine.
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- Method of treating helminthiasis by parenteral administration of sulfoxide derivatives of benzimidazoles
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A method is provided for treating or inhibiting helminthiasis by parenterally administering sulfoxide derivatives of benzimidazoles having the structure STR1 wherein R1 is lower alkyl or phenyl-lower alkyl, R2 and R3 may be the same or different and are hydrogen or lower alkyl, R4 is cycloalkyl, and m is 0 to 3, n is 0 to 3, m + n being ≤ 5. Pharmaceutical compositions for use in the above method are also provided.
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- Certain thiazolidine and tetrahydrothiazine compounds
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Benzene derivatives of the formula: STR1 wherein R1 is alkyl, R2 is a group --SR3, --SOR3, --SO2 R3 or --OR3, in which R3 is alkyl, cycloalkyl, alkenyl, alkynyl, aralkyl, aryl or cycloalkylalkyl, whose position on the benzene ring is either para to --NHCOAZ or para to the heterocyclo group, A is a C1-4 aliphatic hydrocarbon radical, B is a bivalent methylene or ethylene group, and Z is a primary, secondary or tertiary amino group, and acid addition salts and quaternary ammonium derivatives thereof, are new compounds useful as anthelmintics and antifungal agents.
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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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- Benzimidazole derivatives, compositions thereof and method of use as anthelmintics
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Benzimidazole derivatives are providing having the structure STR1 wherein R1 is lower alkyl, phenyl-lower alkyl, halo-lower alkyl, mono-lower alkylaminoalkyl, di-lower alkylaminoalkyl, and alkyl pyridinium halide, R2 and R3 may be the same or different and are hydrogen or lower alkyl, R4 is cycloalkyl or cycloalkenyl, and m is 0 to 3, n is 0 to 3, m + n being ≤5. These compounds are useful as anthelmintic 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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