15 results about "Cyanogen bromide" patented technology

The present invention discloses a method for preparing a bivalent dysentery conjugate combination vaccine, which belongs to the technical field of biological product preparation. The vaccine includes two serotypes, 2a flexneri and sonnei. The O-specific polysaccharides of the two bacteria are covalently bound to a carrier protein according to their unique chemical structure through a corresponding chemical method to prepare a polysaccharide-protein conjugate stock solution. The polysaccharide-protein conjugate stock solution is then adsorbed with an aluminum adjuvant in an appropriate proportion to obtain a dysentery conjugate vaccine. The 2a flexneri dysentery polysaccharide is prepared as a conjugate by a reductive amine method, and the sonnei dysentery polysaccharide is prepared as a conjugate by a direct conjugation method with a spacer. In particular, the present invention no longer uses the highly toxic reagent cyanogen bromide and a high activation pH. The method is free of toxic reagents, has a mild reaction, is easy to control, and is conducive to future large-scale production. The dysentery conjugate vaccine prepared by the present invention is used for the immune prevention of infection with related serotypes of Shigella dysenteriae.

The invention discloses a preparation method of methoxy imidazo [1, 5-a] pyridine, which comprises the following steps: firstly, taking a compound P1, specifically 1-methylamino-3-methoxypyridine, as an initial raw material, and carrying out carbamylation reaction in a formylation reagent to prepare a compound P2, specifically N-[(5-methoxypyridine-2-yl) methyl]; further carrying out intramolecular ring closing reaction on the compound P2 to obtain a compound P3 which is specifically 7-methoxy imidazo [1, 5-a] pyridine; then, a selective bromination experiment at the C3 position is carried out by taking a compound P3 as a parent skeleton and cyanogen bromide (CNBr) as a bromination reagent, and finally, specific bromination of the C3 site of the imidazo [1, 5-a] pyridine with the selectivity of 100% is realized. A solid theoretical basis is laid for efficient specific modification of the low-reaction-activity C3 site, and an efficient synthesis path is provided for rapid construction of the imidazopyridine derivative, so that the imidazopyridine derivative has a wide application prospect.

The present application relates to the technical field of bioengineering, and provides a cyanogen bromide activated agarose gel freeze-drying protective agent, a freeze-dried powder and a preparation and application thereof, the freeze-drying protective agent comprises: a solvent and first and second saccharide substances in the solvent; the first saccharide substance is selected from dextran; the second saccharide substance is selected from monosaccharide and / or disaccharide; and the ratio of the first saccharide substance to the second saccharide substance is (45-55) micromoles to (5-7) millimoles. The present application proposes to use the freeze-drying protective agent to realize the preparation of a freeze-dried powder of cyanogen bromide activated agarose gel by using a low-temperature vacuum freeze-drying method, and the method has the advantages of prolonging the storage period of cyanogen bromide activated agarose gel, facilitating the transportation of cyanogen bromide activated agarose gel and improving the quality of cyanogen bromide activated agarose gel.

The invention discloses a synthesis method of 5-(5-azido-3-nitro-1H-1, 2, 4-triazole-1-yl)-1H-tetrazole sodium salt and an application of the 5-(5-azido-3-nitro-1H-1, 2, 4-triazole-1-yl)-1H-tetrazole sodium salt. A synthesis process of the 5-(5-azido-3-nitro-1H-1, 2, 4-triazole-1-yl)-1H-tetrazole derivative comprises the following steps: (1) carrying out a reaction on 5-azido-3-nitro-1, 2, 4-triazole, cyanogen bromide and sodium azide to generate 5-(5-azido-3-nitro-1H-1, 2, 4-triazole-1-yl)-1H-tetrazole; (2) carrying out a reaction on the 5-(5-azido-3-nitro-1H-1, 2, 4-triazole-1-yl)-1H-tetrazole and sodium hydroxide which is equal to the 5-(5-azido-3-nitro-1H-1, 2, 4-triazole-1-yl)-1H-tetrazole in mole to obtain a 5-(5-azido-3-nitro-1H-1, 2, 4-triazole-1-yl)-1H-tetrazole sodium salt; the-(5-azido-3-nitro-1H-1, 2, 4-triazole-1-yl)-1H-tetrazole sodium salt synthesized by the method is good in free-running property, does not contain heavy metal, is clean and pollution-free in explosive product, has excellent detonating capacity, and is a novel green and environment-friendly initiating explosive.

The invention discloses a synthetic method of 5-(5-azido-3-nitro-1H-1, 2, 4-triazole-1-yl)-1H-tetrazole and an energetic ionic salt of the 5-(5-azido-3-nitro-1H-1, 2, 4-triazole-1-yl)-1H-tetrazole. A synthesis process of the 5-(5-azido-3-nitro-1H-1, 2, 4-triazole-1-yl)-1H-tetrazole derivative comprises the following steps: (1) carrying out a reaction on 5-azido-3-nitro-1, 2, 4-triazole, cyanogen bromide and sodium azide to generate 5-(5-azido-3-nitro-1H-1, 2, 4-triazole-1-yl)-1H-tetrazole; (2) generating corresponding ammonium salt, hydrazinium salt or hydroxylamine salt from the 5-(5-azido-3-nitro-1H-1, 2, 4-triazole-1-yl)-1H-tetrazole and ammonia water, hydrazine hydrate or hydroxylamine solution which is equal to the 5-(5-azido-3-nitro-1H-1, 2, 4-triazole-1-yl)-1H-tetrazole in mole; the preparation method comprises the following steps: reacting 5-(5-azido-3-nitro-1H-1, 2, 4-triazole-1-yl)-1H-tetrazole with equimolar silver nitrate to generate 5-(5-azido-3-nitro-1H-1, 2, 4-triazole-1-yl)-1H-tetrazole silver salt, then reacting the silver salt with guanidine hydrochloride, aminoguanidine hydrochloride or diaminoguanidine hydrochloride, filtering to remove precipitate, concentrating filtrate, and drying to obtain the 5-(5-azido-3-nitro-1H-1, 2, 4-triazole-1-yl)-1H-tetrazole. The corresponding guanidine salt, aminoguanidine salt and diaminoguanidine salt are obtained. The 5-(5-azido-3-nitro-1H-1, 2, 4-triazole-1-yl)-1H-tetrazole synthesized by the method and the energetic ionic salt of the 5-(5-azido-3-nitro-1H-1, 2, 4-triazole-1-yl)-1H-tetrazole have excellent detonation performance and have an application prospect in the aspect of high-energy explosives.

The invention discloses a C-N triazole energetic compound, and belongs to the field of energetic material synthesis. In order to solve the technical problems that an existing triazole intermediate is low in density and poor in thermal stability due to a single structure, a synthesis process depends on a high-risk reagent, and functional modification sites are insufficient, the invention provides a novel high-nitrogen-content diazole compound which is constructed by taking 1, 3, 5-triazine as a mother nucleus and bridging a triazole ring through a C-N bond, and the synthesis comprises two steps: synthesizing 2, 3, 5-triazine into 2, 3, 5-triazine-1, 3, 5-triazine into 2, 3, 5-triazine-1, 3, 5-triazine-1, 3, 5-triazine; the preparation method comprises the following steps: carrying out hydrazinolysis on 2, 4-dichloro-1, 3, 5-triazine and hydrazine hydrate in methanol, and cyclizing with cyanogen bromide in a methanol / water / acetonitrile mixed solvent, thereby obtaining the 2, 4-dichloro-1, 3, 5-triazine derivative. And introducing a nitrogen-containing group through multi-site modification to form an energetic compound or energetic salt. The energetic compound and the energetic salt have high nitrogen content and excellent thermal stability and detonation performance, and are suitable for preparation of high-energy materials such as propellants and initiating explosives.

The application discloses a nucleic acid aptamer capable of specifically recognizing a cyanogen bromide-activated substrate material and application thereof. The nucleic acid aptamer can specifically bind to the cyanogen bromide-activated substrate material and comprises a nucleotide sequence selected from any one of SEQ ID NO: 1-4 in the sequence listing or a nucleotide sequence derived from the nucleotide sequence through substitution, deletion, insertion of one or more nucleotides and / or chemical modification. The application develops a novel nucleic acid probe immobilization method by utilizing the interaction between the nucleic acid aptamer and the cyanogen bromide-activated substrate material and applies the method in the fields of biosensing, affinity enrichment and separation and reagent kit development. In addition, by constructing a fusion allosteric nucleic acid aptamer, the interaction between the two can be used as a signal output strategy to realize detection of target objects such as nucleic acids, proteins, small molecules, cells and exosomes.

The invention relates to the technical field of bioengineering, and provides a cyanogen bromide activated agarose gel freeze-drying protective agent, freeze-dried powder as well as preparation and application of the cyanogen bromide activated agarose gel freeze-drying protective agent and the freeze-dried powder. The first carbohydrate is selected from glucan; the second carbohydrate is selected from monosaccharide and / or disaccharide; the ratio of the first carbohydrate substance to the second carbohydrate substance is (45-55) [mu] mol: (5-7) mmol. By adopting the freeze-drying protective agent, the cyanogen bromide activated agarose gel is prepared into freeze-dried powder by adopting a low-temperature vacuum freeze-drying method, and the method has the advantages that the storage period of the cyanogen bromide activated agarose gel can be prolonged, the cyanogen bromide activated agarose gel is convenient to transport, the quality of the cyanogen bromide activated agarose gel is improved and the like.

The present invention discloses a kind of dinitramine tetracondensed ring high energy density material of linear structure arrangement and its synthesis method. The method is based on 6 (3 amino 1H 1,2,4 triazole 5 bases) 7H [1,2,4] triazole [4,3 b] [1,2,4] triazole 3,7 diamino as raw material, and carries out ring-closure reaction with cyanogen bromide in dilute hydrochloric acid solution to obtain tetracondensed ring compound [1,2,4] triazole [4 ',3 ':1,5] [1,2,4] triazole [3,4 f] [1,2,4] triazole [1,5 d] [1,2,4] triazine 2,5,10 triamino, and then carries out nitration reaction in pure nitric acid to obtain target product DNATT. The synthetic method of the present invention has the characteristics of simple operation, high safety and high yield, and DNATT has higher density and energy, and density is 1.956g / cm 3 The detonation speed reaches 9297m / s, which is higher than that of traditional high-energy explosive Octogen.

The present application belongs to the technical field of culture additive of bacteria, and particularly relates to a preparation method of N-acyl-homoserine lactone. The present application can obtain homoserine and homoserine lactone by lysing methionine through cyanogen bromide after extracting protein from soybean, although other proteins exist in the lysing mixture, but do not have influence on the subsequent ring formation (dehydration). The homoserine lactone salt obtained after ring formation is substituted by alkyl chlorides with different carbon chain lengths, and different AHLs signal molecules can be obtained.

The present invention discloses a 5,6,5-s-triazine ternary fused-ring energetic compound and a preparation method thereof. The energetic compound has the following structural formula: #imgabs0# (I), #imgabs1# (II). The preparation method of the 5,6,5-s-triazine ternary fused-ring energetic compound comprises the following steps: A1, preparing 1,3-dinitro-1,2,4-triazole and using the 1,3-dinitro-1,2,4-triazole to prepare compound 1; A2, dissolving compound 1 in water, adding cyanogen bromide, and stirring at room temperature for 24 hours. Filtering the precipitate and washing it with water to obtain an energetic compound having structural formula (I). The present invention utilizes two C‒N-linked bisazole compounds as raw materials, water as a solvent, and ring-closing with cyanogen bromide to obtain two 5,6,5-s-triazine ternary fused-ring energetic compounds having high thermal decomposition temperatures, low mechanical sensitivity, and exhibiting high energy and stability.

The invention discloses a preparation method and application of a fatty acid transporter FATP transmembrane domain. The method comprises the following steps: fusing a gene for coding an FATP transmembrane domain with a TrpLE tag sequence, and performing high-efficiency expression in escherichia coli to form an inclusion body. Thirdly, primarily purifying the fusion protein by using nickel column affinity chromatography, and specifically releasing a target transmembrane peptide fragment through cyanogen bromide chemical cleavage; and finally, carrying out fine purification by adopting one-step reversed-phase high-performance liquid chromatography to obtain a milligram-grade high-purity peptide fragment. The purified peptide fragment can be successfully reconstructed in a plurality of membrane simulation systems such as Fos-choline-14 micelles or DMPC / DHPC (Dimethyl Polycarbonate / Dimethyl Hexaphthyl Polycarbonate) lipid saucers and the like. According to the method, high-level expression of the FATP transmembrane domain in escherichia coli is achieved, the purification process is simple, convenient and efficient, the final product is high in purity, the yield can reach the milligram level, and the method is suitable for stable isotope labeling and meets the requirements of fine structure research such as nuclear magnetic resonance.

The application discloses high-purity chicken plasma fibronectin and a preparation method thereof. The method comprises the following steps: taking fresh chicken plasma as raw material, adding ammonium sulfate to a saturation degree of 20% at low temperature to realize targeted extraction and enrichment of fibronectin; then, a gelatin affinity chromatography column is prepared through gelatin-cyanogen bromide (CNBr) activation gel coupling, specific binding of fibronectin and gelatin is utilized to realize efficient capture and preliminary purification, and gradient arginine solution is adopted to realize impurity washing and elution; finally, high-purity and high-activity fibronectin is obtained through desalination of dextran gel G25 chromatography. Through optimization of the combination process of ammonium sulfate precipitation, specific affinity chromatography and gel filtration, the problems of low purity, easy damage of activity, low efficiency and high cost in the traditional method are solved, the purpose of high-value preparation of high-purity fibronectin from by-product chicken blood is realized. The purity can reach 92.93%, and the high-purity chicken plasma fibronectin can be applied to the fields of biomedicine, cosmetics and cell culture.

The invention belongs to the technical field of synthesis of perfluoronitrile compounds, and particularly relates to a method for continuously synthesizing perfluoroisobutyronitrile, which comprises the following steps of: mixing gasified 2-bromoheptafluoropropane and cyanogen bromide, preheating, reheating, carrying out cyanation reaction, cooling to obtain cooling liquid and mixed gas, and compressing, condensing, rectifying and drying the mixed gas to obtain the perfluoroisobutyronitrile. The perfluoroisobutyronitrile preparation method disclosed by the invention can realize continuous production, and has the advantages of simple process, low production cost, mild reaction conditions and no need of a catalyst and a solvent.

The subject of this invention is a construct of an expression vector for expressing recombinant µ-conotoxin TIIIA or TIIIAlaMut, characterized in that it comprises the nucleotide sequence of µ-conotoxin TIIIA SEQ ID NO:1 or the nucleotide sequence of µ-conotoxin TIIIAlaMut SEQ ID NO:4, both sequences containing a sequence encoding six histidine residues (6His) at the 5' end, which is linked via a serine-glycine-serine linker (SGS) to a construct encoding a TRX::TIIIA fusion protein or a TRX::TIIIAlaMut fusion protein, wherein the TRX::TIIIA fusion protein comprises the µ-conotoxin TIIIA gene and a gene encoding a leader protein, and the TRX::TIIIAlaMut fusion protein comprises the µ-conotoxin TIIIAlaMut gene and a leader protein, wherein the leader protein is a thioredoxin (TRX) modified by site-directed mutagenesis, wherein the amino acid methionine at position 37 is replaced by lysine. Another subject of the invention is an expression vector comprising a construct according to the invention under the control of a constitutive promoter. Another subject of the invention is isolated *E. coli* cells comprising an expression vector according to the invention. Another subject of the invention is a method for producing µ-conotoxin TIIIA or TIIIAlaMut in *E. coli* using an expression vector comprising a construct according to the invention, characterized in that the method comprises the steps of: a) transforming *E. coli* cells with an expression vector comprising a construct according to the invention under the control of a constitutive promoter, said expression vector encoding a TRX::TIIIA fusion protein having the amino acid sequence SEQ ID NO:2 or having SEQ ID NO:2. a) TRX::TIIIAlaMut fusion protein NO:5; b) Expression of the TRX::TIIIA or TRX::TIIIAlaMut fusion protein; c) Isolation and purification of the TRX::TIIIA or TRX::TIIIAlaMut fusion protein; d) Formation of disulfide bonds by glutathione treatment of the purified TRX::TIIIA or TRX::TIIIAlaMut fusion protein in GSH / GSSG and dialyzing in buffer; e) Cleavage of the TRX::TIIIA or TRX::TIIIAlaMut fusion protein with the formed disulfide bonds by cyanogen bromide; f) Purification of the cleaved TIIIA or TIIIAlaMut peptide.