- Conformational transformations and autooxidation of 5-bromo-2-(2-methylpropyl)-5-nitro-1,3,2-dioxaborinane
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Conformational study of 5-bromo-2-(2-methylpropyl)-5-nitro-1,3,2-dioxaborinane at the DFT PBE/3ξ level of theory revealed the only sofa–sofa interconversion pathway through a transition state corresponding to 2,5-twist conformer. The barrier to internal rotation of the axial nitro group is several times higher than that for the equatorial nitro group. According to the 1H, 13C, and 11B NMR, IR, and X-ray diffraction data, the main autooxidation products of 5-bromo-2-(2-methylpropyl)-5-nitro-1,3,2-dioxaborinane are 2-bromo-2-nitropropane-1,3-diol and boric acid.
- Valiakhmetova, O. Yu.,Tyumkina,Meshcheryakova,Khalilov,Kuznetsov
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- New reaction of the sodium salt of 2-nitroethanol. X-ray analysis of the sodium salt of 2-oxo-3-hydroxypropionic acid oxime, 2-bromo-2-nitropropane-1,3-diol, and the model 2,2-dinitropropane-1,3-diol
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A novel reaction of the sodium salt of 2-nitroethanol in aqueous ammonia resulted in the sodium salt of 2-oxo-3-hydroxypropionic acid oxime (1) has been found. Bromination of 1 affords 2-bromo-2-nitropropane-1,3-diol (2) with a previously unknown molecular conformation. The formation mechanisms of compounds 1 and 2 were suggested. X-ray analysis of products 1, 2 and that of the model compound, 2,2-dinitropropane-1,3-diol, was performed.
- Fedorov,Golovina,Arakcheeva,Trofimova,Atovmyan
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- Preparation method of bronopol
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The invention discloses a preparation method of bronopol. The method is characterized by comprising the following steps: reacting a compound 1A with a nitration reagent to obtain a compound 2A; and carrying out hydrolysis reaction on the compound 2A and water, reacting with a bromination reagent to obtain a bronopol crude product, and purifying to obtain a bronopol fine product. According to the method, a reagent with low price is used as an initial raw material, a final product is obtained through reactions such as nitrification, hydrolysis and bromination, the reaction conditions of each step are mild, the yield of the obtained bronopol is high, and the cost can be greatly reduced.
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Paragraph 0034; 0037-0038
(2021/04/21)
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- A PROCESS FOR THE PREPARATION OF BRONOPOL
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The invention provides a process for preparing bronopol, which process comprises charging a reaction vessel with water, bromopicrin, nitromethane and paraformaldehyde, gradually feeding a base into said reaction vessel under stirring, bringing the reaction to completion and separating bronopol from the aqueous reaction mixture.
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Page/Page column 22-24
(2009/10/21)
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- Method and composition for preserving antigens and process for utilizing cytological material produced by same
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A method and composition for fixing and stabilizing tissues, cells, and cell components such that the antigenic sites are preserved for a useful period of time is provided. The fixative employs a formaldehyde donor that is non-toxic, non-flammable, and that stabilizes the cell with minimal damage to and alteration of the cell morphology. The cell antigenic sites are left intact so that studies with monoclonal antibodies may be conducted. Vaccines and related immunotherapeutic methods utilizing antigens stabilized by the fixative of the present invention are also provided. The invention also discloses a method for developing a positive control for test reagents and for test instrumentation.
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- Method and composition for preserving antigens and nucleic acids and process for utilizing cytological material produced by same
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A method and composition for fixing and stabilizing tissues, cells, and cell components such that the antigenic sites and nucleic acids are preserved is provided. The fixative employs a formaldehyde donor that is non-toxic, non-flammable, and that stabilizes the cell with minimal damage to and alteration of the cell morphology. The cell antigenic sites are left intact so that studies with monoclonal antibodies may be conducted. Vaccines and related immunotherapeutic methods utilizing antigens stabilized by the fixative of the present invention are also provided. Also disclosed is a method for developing a positive control for test reagents and for test instrumentation.
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- Aqueous isothiazolone formulation
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An aqueous isothiazolone formulation useful for antiseptic or antifungal treatment of various synthetic polymeric emulsions, which comprises (a) a specific isothiazolone compound, (b) water or an aqueous solvent and (c) a specific nitrobromo or cyanobromo compound.
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- Process for the preparation of 5-bromo-5-nitro-1,3-dioxane
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Unpurified 2-bromo-2-nitro-1,3-propanediol is used as the starting material for a process for the preparation of 5-bromo-5-nitro-1,3-dioxane from 2-nitro-1,3-propanediol without the use of an organic solvent on an industrial scale. This is carried out in such a way that in a first stage a mixture of bromine and aqueous hydrogen bromide solution is cooled and an aqueous solution of an alkali metal or an alkaline-earth metal salt of 2-nitro-1,3-propanediol is added at such a rate that, with cooling, the maximum reaction temperature does not exceed 30° C., and then in a second reaction stage paraformaldehyde and sulfuric acid are added, left to react above room temperature, and the organic phase separated.
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- Novel process for the preparation of bronopol
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A process of forming 2-bromo-2-nitro-1,3-propanediol by contacting a 5-nitro-1,3-dioxane with bromine under alkaline conditions and hydrolyzing the brominated product.
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- 5-Bromo-5-nitro-2-alkylsubstituted-1,3-dioxane
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5-Bromo-5-nitro-2-alkylsubstituted-1,3-dioxanes, such as 5-bromo-2-methyl-5-nitro-1,3-dioxane, novel antimicrobials with activity against both bacteria and fungi.
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