67 results about "3-Aminopyridine" patented technology

The invention discloses a preparation method for 2,3-dichloropyridine. The preparation method creatively comprises the steps of reacting nicotinamide serving as an active ingredient with sodium hypochloride to prepare 3-aminopyridine, distilling to remove water, extracting with dichloromethane to recover 3-aminopyridine, wherein the yield of the 3-aminopyridine is more than or equal to 93%; reacting the 3-aminopyridine hydrochloric acid solution with hydrogen peroxide to obtain 2-chlorino-3-aminopyridine hydrochloric acid solution, wherein the yield of the 2-chlorino-3-aminopyridine is more than or equal to 85%; then performing diazotization and sandmeyer reaction to obtain 2,3-dichloropyridine. The preparation method is less in side reaction, an intermediate product is not required for refining, and the product is high in content and yield, simple in technology and easy to operate.

The invention discloses a method for preparing 2,3-dichloropyridine with a simple process and a high yield rate. The method is as follows: in a concentrated hydrochloric acid, 3-aminopyridine is used as a starting material, Fe<2> or Fe <3> is used as a chlorination catalyst, and a mixture of hydrogen peroxide and hydrochloric acid or chlorine is used as a chlorating agent to conduct a chlorination reaction to chloridize the 3-aminopyridine. The reaction mixtures without being separated are added with Cu<+> or Cu<2+> which serves as a catalyst for diazotization/chlorination reaction and with an aqueous solution sodium nitrite to conduct diazotization/chlorination reaction to prepare 2,3-dichloropyridine by a one-pot process. The 2,3-dichloropyridine is isolated and purified by a normal method with a purity more than 99.2 percent. According to a 3-aminopyridine based calculation, the molar yield rate of the 2,3-dichloropyridine is more than 74.1 percent.

A Synthesis of 2, 3-dichloro-pyridine, including steps as follows: 1)liquating the raw material of 3-aminopyridine in decuple-twelvefold mass thick alcaine at the condition of mixing, cooling to 4-5 deg C, adding equal mol mass hydroperoxide as raw material, controlling reaction temperature between 6-8deg Cand mixing for 1-2h at the same temperature after adding the things; 2) cooling the solution below 0deg C, adding equal mol mass erinitrit solution as raw material and then preserving heat for 0. 5-1h; 3) controlling the reaction temperature below 0deg C, adding miscible liquids of 0. 15 times mol mass copper chloride as the raw material and duple mass as thick alcaine, then preserving heat for a half hour at least; 4) Returning reactant to ambient temperature and doing extraction by dichloromethane; 5) vacuum distilling the tobacco extract to dry will get product. The intermediate products of the invention are never purified and moved, all the procedures can be done in the same reaction pot and the three step reaction only uses alcaine which contains reactant as solution.

The present invention relates to methods of treating viral or fungal infections using 3-aminopyridine-2-carboxyaldehyde thiosemicarbazone (3-AP) and 3-amino-4-methylpyridine-2-carboxaldehyde thiosemicarbazone (3-AMP) and its prodrug forms and to pharmaceutical compositions comprising these compounds.

The invention relates to a pyridylurea biquaternary ammonium salt as well as a preparation method and application thereof. The preparation method of the pyridylurea biquaternary ammonium salt comprises the following steps: using 3-aminopyridine as a staring material, conducting reaction on 3-aminopyridine and triphosgene to obtain 1,3-bi(3-pyridyl)urea, and conducting reaction on 1,3-bi(3-pyridyl)urea and alkyl bromide under the solvent-free condition to prepare the pyridylurea biquaternary ammonium salt. According to the method, a solvent-free method is adopted to prepare the pyridylurea biquaternary ammonium salt, so that the environment can be protected, and the yield is relatively high. The provided pyridylurea biquaternary ammonium salt can be used as a plant growth regulator to promote plant cell division, and the problem that the traditional phenylurea plant growth regulator is poor in water solubility is solved.

The present invention is based on the discoveries that PAN-811 (1) reduces infarct volume, suppresses brain edema and decreases mortality associated with ischemia; (2) blocks veratridine-induced swelling and neuronal cell death; (3) chelates free calcium and inhibits MMP-9 activity; and (4) blocks calcium-induced neuronal cell death and suppresses glutamate-induced calcium influx into neuronal cells. More particularly, the present invention relates to methods for treating, ameliorating or preventing vasogenic and/or cytotoxic brain edema, by administering to a subject in need thereof certain thiosemicarbazone compounds or pharmaceutically acceptable salts thereof. An example of such a thiosemicarbazone is 3-aminopyridine-2-carboxaldehyde thiosemicarbazone (PAN-811).

Disclosed herein is the use of aminopyridines, such as 3-aminopyridine, 4-aminopyridine or 3,4-diaminopyridine, in the management and treatment of cerebral palsy patients of all ages.

The invention relates to the daily chemical field and the pharmaceutical industry, in particular to benzaldehyde Schiff base type aminopyridine acetylated starch and preparation thereof. The structural formula of the benzaldehyde Schiff base type aminopyridine acetylated starch is shown as the formula (1). A preparation method comprises the following steps: firstly, starch reacts with chloroacetyl chloride, then various types of benzaldehyde react with 3-aminopyridine, Schiff bases are prepared, chloroacetyl starch reacts with the prepared Schiff bases finally, and the benzaldehyde Schiff base type aminopyridine acetylated starch shown as the formula (1) is obtained through purification, wherein the molar weight of chloroacetyl chloride is 1-2 times that of the starch, and the molar weight of various types of the Schiff bases is 2-3 times that of the chloroacetyl starch. The reaction is simple, convenient and efficient, popularization is easy, and required equipment and raw materials are easy to obtain. Research proves that the derivative has good water solubility and bacteriostatic activity, the biological activity of the starch is enhanced, the application range of the starch is enlarged, and the starch and the preparation method can be widely applied to the fields of daily chemical and pharmaceuticals.

The invention belongs to the field of organic synthesis and particularly relates to a preparation method of 2-methyl-3-bromopyridine. The preparation method includes the following steps that 1, diethyl malonate reacts with alkali metal to generate salt, then a methylbenzene solution of 2-chlorine-3-nitropyridine is added dropwise to be conducted a condensation reaction, and the 2-methyl-3-nitropyridine is obtained through decarboxylation under an acidic condition; 2, under the catalysis of Pd/C, methanol serves as a solvent, a hydrogenation reduction and suction filtration are conducted on the 2-methyl-3-nitropyridine, filtered liquid is condensed, and 2-methyl-3-aminopyridine is obtained; 3, the 2-methyl-3-aminopyridine reacts with acid to generate salt, the cooling is conducted to enable the temperature to be in -10 DEG C-0 DEG C, bromine is added dropwise, after the addition, then a sodium nitrite solution is added dropwise, after addition, pH of the solution is adjusted to be alkaline, then extracting, drying and concentration are conducted, and the 2-methyl-3-bromopyridine is obtained. The preparation method of the 2-methyl-3-bromopyridine has the advantages that the reaction condition is moderate, the operation is easy, the post-processing is simple, enlarged production is easy, and the preparation method is very suitable for industrial production; the catalysis effect is good, and the reaction yield ratio is high; the price of the raw material is low, and the production cost is low.

The invention discloses a preparation method for high purity 2-chlorine-3-aminopyridine hydrochloride, which comprises choosing 3-aminopyridine as a raw material to be chloridized to obtain 2-chlorine-3-aminopyridine reaction liquid, adjusting a potential of hydrogen (pH) value, adopting an organic solvent to extract, dewatering extraction liquid to form the 2-chlorine-3-aminopyridine hydrochloride with hydrogen chloride, and stirring to crystallize at the appropriate temperature to achieve the 2-chlorine-3-aminopyridine hydrochloride with the purity >= 99%. Impurities of 2,6-dichloro-3-aminopyridine are smaller than or equal to 0.5%. the preparation method is simple in operation, little in equipment investment, low in cost, small in environment pollution and suitable for industrialization production.

The invention relates to the field of medicine and chemical industry. Aims at solving problems of high trifluoromethylation reagent toxicity, or high cost, complicated reaction, and low conversion rate existing in synthesizing reactions of trifluoromethylation similar compounds, the invention provides a synthesizing method of 2-trifluoromethyl-3-fluoropyridin. The method comprises the steps that: (2) with 2-trifluoromethyl ethyl nicotinate as a raw material, 2-trifluoromethyl-3-aminopyridine is produced through a reaction; and (2) the product obtained in the step (1) is subjected to a reaction with fluoboric acid, such that 2-trifluoromethyl-3-fluoropyridin is obtained. According to the invention, the raw materials have low cost, and are easy to obtain. Also, post treatment is simple. The method is suitable for laboratory small-scale preparation, and is suitable for large-scale industrialized production.

The invention discloses a nitrogen-substituted podophyllotoxin derivative with anti-tumor activity and a preparation method and use thereof. According to the method, 2-aminopyrimidine, 2-aminopyridine, 2-amino-3-methylpyridine, 2-amino-4-methylpyridine, 2-amino-5-methylpyridine, 2-amino-4,6-dimethyl pyridine, 3-aminopyridine, 3-amino-4-methylpyridine, 5-amino-2-methylpyridine, 3-amino-2-chloropyridine or 4-amino-2-chloropyridine is respectively introduced to an activated C-ring fourth position of a podophyllotoxin compound through nitrogen substitution reaction, so as to obtain the nitrogen-substituted podophyllotoxin derivative, represented by a formula (V) shown in the specification, with excellent anti-tumor activity. The nitrogen-substituted podophyllotoxin derivative disclosed by the invention acts on tumor cells through multiple ways and multiple target points, and the anti-tumor activity of the nitrogen-substituted podophyllotoxin derivative is remarkably improved compared with that of the podophyllotoxin compound. The compound disclosed by the invention can be used for preparing anti-tumor drugs and is clinically applied to anti-tumor treatment.

The invention provides a medicinal composition, which contains an effective dose of 3-aminopyridine-2-formaldehyde thiosemicarbazone for treating cancers and a pharmaceutically acceptable carrier. The invention also provides a composition for oral taking, which contains an effective dose of 3-aminopyridine-2-formaldehyde thiosemicarbazone and the acceptable carrier. The invention also provides the medicinal composition for intravenous administration, which contains 3-aminopyridine-2-formaldehyde thiosemicarbazone in an amount which is enough for supplying about 100 to 200mg/m<2> to an acceptor every day. Finally, the invention provides a container which can prevent 3-aminopyridine-2-formaldehyde thiosemicarbazone from decomposing and being damaged in light and contains at least an effective dose of 3-aminopyridine-2-formaldehyde thiosemicarbazone.

The invention discloses a synthesis method of 3-cloro-5-bromo-2-picolinic acid, and belongs to the field of chemosynthesis. According to the method, 3-aminopyridine is used as raw materials; concentrated hydrochloric acid and hydrogen peroxide are added for preparing a diazonium salt solution; CuCl, dichloromethane and concentrated hydrochloric acid are added into a three-mouth flask; the diazonium salt solution is dropwise added into the three-mouth flask; the pH value is regulated; extraction, separation and rotary evaporation are carried out to obtain 2, 3-dichloropyridine; absolute ethyl alcohol is used for dissolution; a hydrazine hydrate solution is dropwise added into the flask; under the nitrogen gas protection, backflow is carried out; 3-cloro-2-cyanopyridine can be obtained; then, through specific conditions, the 3-cloro-2-cyanopyridine is used for producing 3-chloropyridine-2-picolinic acid; then, N-bromo-succinimide is added for performing a bromination reaction to finally obtain the 3-cloro-5-bromo-2-picolinic acid.

The invention discloses a synthetic method for 5-bromine-2-methylpyridine: using 6-methyl-3-picolinic acid as the raw material to react with ethyl alcohol to generate 6-methyl-3-picolinic acid ethyl ester; carrying out ammonolysis reaction by aqueous ammonia on the 6-methyl-3-picolinic acid ethyl ester to generate 6-methyl-3-pyridine carboxamide; carrying out Hofmann degradation reaction to obtain 6-methyl-3-aminopyridine; and finally reacting the 6-methyl-3-aminopyridine with a bromizing reagent to generate 5-bromine-2-methylpyridine. In the method, the process reaction condition is mild, the yield is high, the raw material is available, the cost is lower, and no 3-subsidary products are generated in the whole process, the load of post separation is eliminated and the prospect of industrialization is good.

The invention provides a process study for synthesizing 2,3,6-trichloropyridine from nicotinamide. The process study comprises the following steps: with nicotinamide as a raw material, adding a sodiumhypochlorite solution in an alkaline environment to carry out a Hofmann downgrading reaction to obtain 3-aminopyridine; under catalysis of a Lewis acid catalyst, performing chlorination reaction under a concentrated hydrochloric acid/hydrogen peroxide condition to obtain 2,6-dichloro-3-aminopyridine; and reacting in the presence of sodium nitrite under low temperature and strong acid conditions to form a diazonium salt solution; and finally, performing a Sandmeyer reaction to obtain the target product, 2,3,6-trichloropyridine. The process material provided by the invention is simple, easily available and cheap, the reaction condition is simple and easy to operate, the post-treatment is simple, the yield is high, and thus the process has good industrial development prospects.

The invention relates to a method for preparing a poly-substituted 1, 5-naphthyridine compound. The method comprises the steps of: mixing 3-aminopyridines compound shown in constitutional formula (II), (III) or (IV) with 2-alkenyl aldehyde or 2-alkenyl ketone; adding green vitriol as a catalyst; carrying out heating reflux reaction in sulphuric acid for 2 to 20 hours; cooling a reaction system till the temperature of the reaction system reaches room temperature and then regulating pH value to be neutral; filtering the reactants and extracting, concentrating, separating and refining the filtrate to obtain the poly-substituted 1, 5-naphthyridine compound shown in constitutional formula (I). The method can be applied to various substrates and materials are highly available; poly-substituted 1, 5-naphthyridine compound banks with diverse structures can be synthesized by optimizing and regulating substrates involved in the reaction, and the compounds can be widely applied to the fields such as pharmacochemistry, biomedicine, materials science and the like.

The invention belongs to the field of fine chemical industry, and particularly relates to a preparation method of 2-chloro-3-aminopyridine. The method comprises the following steps: adding 2-chloro-3-nitropyridine into water, and dropwisely adding a sodium sulfide water solution to carry out reaction; after the reaction finishes, cooling to precipitate a solid, adding dilute hydrochloric acid to dissolve the solid, filtering, regulating the pH value of the filtrate to 9-10 with an NaOH water solution, and precipitating crystals, thereby obtaining the 2-chloro-3-aminopyridine. The preparation method of 2-chloro-3-aminopyridine has the advantages of mild reaction, high product yield and the like, is simple to operate, and is suitable for industrial production; no organic solvent is used in the reaction process, thereby being beneficial to clean production; and the raw materials are cheap and accessible, thereby lowering the production cost.

The invention discloses a method for synthesizing pirenzepine hydrochloride, comprising the following steps of: (1) by taking 2-chloro-3-aminopyridine and methyl anthranilate as raw materials, a palladium compound as a catalyst, a phosphorous compound as a ligand and a benzene solvent as a solvent, reacting all the materials under the action of alkali to obtain a cyclization midbody benzodiazepinone; (2) carrying out acylation reaction on the cyclization midbody benzodiazepinone and chloroacetyl chloride in the solvent under the action of alkali to obtain N-chloracetyl-benzodiazepinone, and reacting the N-chloracetyl-benzodiazepinone with N-methyl piperazine to obtain pirenzepine; and (3) heating the pirenzepine in the presence of concentrated hydrochloric acid to obtain pirenzepine hydrochloride. The method provided by the invention is characterized in that palladium is employed as the catalyst, the reaction raw materials are simple, the reaction conditions are mild, and the reaction yield is high, which can be 95 or higher. The method is low in associated reaction corrosion, low in three-waste treatment load, simple in process, low in cost and capable of meeting the industrial production requirements.

The invention belongs to the field of chemical industry and discloses a novel method for synthesizing 2,5-dichloro-3-fluoropyridine. The method comprises the following steps of: performing Hofmann degradation on 2,5-dichloro-nicotinamide under the action of sodium hypobromite or sodium hypochlorite to obtain 2,5-dichloro-3-aminopyridine, and performing diazotization reaction on the 2,5-dichloro-3-aminopyridine, fluoboric acid and sodium nitrite to obtain the 2,5-dichloro-3-fluoropyridine. By the method, the yield of the 2,5-dichloro-3-fluoropyridine is greatly improved, and the total yield of the 2,5-dichloro-3-fluoropyridine can reach over 67 percent at most; and expensive 2,3,5-trichloropyridine is not used, and an expensive fluridizer is not used, so that the synthetic cost of the 2,5-dichloro-3-fluoropyridine is greatly reduced. Moreover, reaction steps are simple, the reaction process is mild, and the method is easy to control.