645 results about "Piperazine" patented technology

The invention belongs to the technical field of membrane separation, and particularly relates to a method for preparing a high-flux hollow fiber nanofiltration membrane based on interfacial polymerization, the obtained membrane and application. The method comprises the following steps: firstly, carrying out pre-adsorption treatment on a polyethersulfone hollow fiber ultrafiltration base membrane through a polyethyleneimine aqueous solution to form a reactive anchoring layer; then sequentially dipping in an aqueous phase solution containing piperazine, sodium phytate and nanoscale cellulose whiskers and an organic phase solution containing trimesoyl chloride and 5-isocyanate isopeptide acyl chloride for interfacial polymerization; and finally, carrying out heat treatment on the obtained primary composite membrane, and completing a gas-phase cross-linking reaction in a glutaraldehyde steam atmosphere. According to the method, the hollow fiber nanofiltration membrane with high flux, high selectivity, excellent chlorine resistance and pollution resistance is successfully prepared through a multi-stage strengthening process, and the hollow fiber nanofiltration membrane is suitable for the fields of drinking water purification, industrial wastewater reuse, material separation and the like.

The invention relates to a thermoplastic molding composition (P) comprising: (A) thermoplastic polymer composition (A) comprising: (A-1) 10 to 50 wt.-% of graft copolymer (A-1), (A-2) 1 to 50 wt.-%, of thermoplastic polymer matrix (A-2) based on one or more vinylaromatic copolymers, (A-3) 20 to 50 wt.-%, of polymerized alkyl methacrylate component (A-3), and (A-4) 0 to 45 wt.-% of comonomer which is copolymerized with the at least one polymerized alkyl methacrylate component (A-3), where the sum of (A-1), (A-2), (A-3) and optional comonomers (A-4) is 83.2 to 99.8 wt.-%; (B) a hindered amine light stabilizer composition (B), comprising at least two of substances (B-1) to (B-3): (B-1) 0 to 0.9 wt.-%, of at least one hindered amine light stabilizer having a dipiperidine structure with at least one alkyl group at each of the 2 and 6 positions of the dipiperidine structure (B-2) 0 to 0.9 wt.-%, of a hindered amine light stabilizer mixture having a monopiperidine structure with at least one alkyl group at each of the 2 and 6 positions of the monopiperidine structure, and (B-3) 0 to 2 wt.-%, of at least one hindered amine light stabilizer having a polymeric structure comprising piperidine groups with at least one alkyl group at each of the 2 and 6 positions of the piperidine groups (C) 0 to 5 wt.-%, of one or more further additives (C), different from (B); and (D) 0 to 10 wt.-%, of colorants, dyes and / or pigments (D), different from (C); wherein the constituents (A) to (D) sum up to 100 wt.-% of the molding composition (P).

The invention relates to the technical field of organic photoelectric materials, and particularly discloses a non-condensed ring small molecule acceptor material based on a quinonoid structure as well as a preparation method and application of the non-condensed ring small molecule acceptor material. According to the invention, easily available 1, 4-diacetyl piperazine-2, 5-diketone is used as a center, an alkyl chain and Ar are used for modification, EG is used as an end group, the non-condensed ring A-D-A '-D-A type structure acceptor material based on a quinone structure is constructed, and the general formula is shown in the specification. Wherein the PCE of the acceptor material which is modified by bithiophene and takes 2-(3-ethyl-4-oxothiazolidine-2-subunit) malononitrile as a terminal group reaches 15%. The non-condensed ring small molecule acceptor material based on the quinonoid structure is simple in synthesis process, and an effective strategy is provided for solving the problem of the overall performance of an organic solar cell.

The invention provides an epoxy adhesive solution composition, a preparation method of an epoxy adhesive solution and a modified cellular board. The epoxy adhesive liquid composition comprises the following components in parts by weight: 53-58 parts of epoxy resin, 2-10 parts of a silane coupling agent, 1-10 parts of a curing agent, 1-5 parts of blocked isocyanate and 60-70 parts of water, wherein a blocking group of the blocked isocyanate is selected from hydroxyl, oximido, acylamino, amino, imidazolyl, pyrazolyl or piperazinyl. By introducing the blocked isocyanate with the specific structure, the epoxy adhesive liquid can be subjected to pre-crosslinking reaction in the early drying treatment process, the modulus and high temperature resistance of a formed dry film are improved, and the phenomenon of glue overflow in the subsequent curing stage is inhibited; therefore, the structural integrity and the bonding strength of the adhesive layer in the modified cellular board under the high-temperature condition are improved.

The invention provides a Lewis acid metal ion-piperazine modified nanocellulose film as well as a preparation method and application thereof, and belongs to the technical field of battery materials. The preparation method comprises the following steps: mixing carboxylated nanocellulose with Lewis acidic metal salt in a solution, and carrying out pre-crosslinking reaction to obtain Lewis acidic metal ion modified carboxylated nanocellulose; a piperazine ligand compound and dopamine hydrochloride are added into the Lewis acidic metal ion modified carboxylated nano-cellulose, a cross-linking reaction is carried out with Lewis acidic metal ions as the center, suction filtration is carried out, and a film is formed. The metal in the Lewis acid metal salt is metal cations with the valence of more than bivalent. The carboxylated nanocellulose, the Lewis acid metal ion-piperazine complex and the solid polymer electrolyte are organically combined together for the first time and are applied to the lithium metal battery, the unique advantages of the lithium metal battery in the field of batteries are shown, and the rate capability and the cycling stability are greatly improved.

Methods for treating patients with wAIHA comprising administering at least one compound chosen from (R)-2-[3-[4-amino-3-(2-fluoro-4-phenoxy-phenyl)pyrazolo[3,4-d]pyrimidin-1-yl]piperidine-1-carbonyl]-4-methyl-4-[4-(oxetan-3-yl)piperazin-1-yl]pent-2-enenitrile (rilzabrutinib) and pharmaceutically acceptable salts thereof are disclosed.

The invention provides epoxy resin for halogen-free flame-retardant self-leveling powder coating and a preparation method of the epoxy resin, and belongs to the technical field of powder coating. The flame retardant is mainly prepared from anhydrous piperazine, bisphenol A diglycidyl ether, trihydroxymethyl phosphorus oxide, triethyl phosphite, epoxy chloropropane, sodium hydroxide, N-methyl iminodiacetic acid, ethylene glycol diglycidyl ether and other main raw materials through polymerization. The prepared epoxy resin and 2-phenylimidazoline are subjected to low-temperature curing (135 DEG C / 20 min) on the premise that an additional flatting agent does not need to be used, the flexibility of a coating film is good, the impact resistance grade is high, the impact performance reaches the condition that no cracking phenomenon exists in the front and back 60cm, the leveling grade reaches the grade 7 or above, the gloss is high and reaches 95% or above, the oxygen index reaches 34% or above, and the halogen-free flame retardant performance is excellent.

The invention relates to the technical field of polyamide nanofiltration membranes, in particular to an acid and alkali resistant high-strength nanofiltration membrane and a preparation method thereof. The problem that the strength and the acid and alkali resistance of a polyamide nanofiltration membrane in the prior art cannot be considered at the same time is solved. The base membrane material of the polyamide nanofiltration membrane is modified polyethersulfone and is obtained by chemically bonding a carbon nanotube subjected to double surface modification by titanium dioxide sol-gel and a KH550 coupling agent in a polyester non-woven fabric, and the modulus of the material is improved by utilizing an inorganic-organic hybrid network; the functional layer of the polyamide nanofiltration membrane is made of modified polyamide, and the modified polyamide functional layer is formed by forming a polyamide matrix through polymerization reaction of 2, 2 '-disulfonic acid-4, 4'-diaminobiphenyl, piperazine and trimesoyl chloride and introducing 4-amino-2, 2, 6, 7-tetramethyl-1, 3-pentanediol at the same time. And the chemical resistance is improved by a free radical capturing group generated by 2, 2, 6, 6-tetramethylpiperidine and octa-isobutyl cage type silsesquioxane.

The invention relates to the field of sheath materials, and discloses an anti-aging sheath material for an electronic wire and a preparation method thereof, the sheath material comprises low density polyethylene, an ethylene-vinyl acetate copolymer, an ethylene-octene copolymer, ethylene propylene diene monomer, a triazine ring derivative, ammonium polyphosphate, modified nano silicon dioxide and an auxiliary agent; according to the triazine ring derivative, N-butyl-2, 2, 6, 6-tetramethyl-4-piperidylamine reacts with cyanuric chloride to prepare a triazine ring monosubstituent, hydrazine hydrochloride is used as a bridging agent to react with the triazine ring monosubstituent, and the triazine ring derivative and piperazine are polymerized to prepare the triazine ring derivative. The modified nano silicon dioxide is prepared by enabling 3-(3, 5-di-tert-butyl-4-hydroxyphenyl) propionyl chloride and 4-propenyloxy-2-hydroxybenzophenone to react, and carrying out free radical polymerization on the reaction product on the surface of the nano silicon dioxide. The synergistic effect of mechanical property, thermo-oxidative aging resistance, ultraviolet aging resistance and flame retardant property is realized.

A novel salt form of Compound (I) represented by the following structural formula, and its corresponding pharmaceutical compositions, are disclosed.Particular single crystalline forms of 1:1 Compound (I) tartrate salt are characterized by a variety of properties and physical measurements. Methods of preparing specific crystalline forms are also disclosed. The present disclosure also provides methods of treating cancer in a subject.

The invention discloses a catalyst for one-step synthesis of piperazine and N-hydroxyethyl piperazine from hydroxyethyl ethylenediamine as well as preparation and application of the catalyst. The method comprises the following steps: mixing an active component soluble salt and an auxiliary agent soluble salt, and dissolving to obtain a soluble salt solution; dropwise adding the soluble salt solution and the precipitant solution into the bismuth-containing carrier solution under stirring for precipitation reaction, wherein the pH value of the reaction solution is controlled to be 9-11 in the precipitation process; and after the precipitation is finished, aging, filtering, washing, drying, roasting and carrying out reduction activation to prepare the catalyst for synthesizing piperazine and N-hydroxyethyl piperazine in one step by using hydroxyethyl ethylenediamine. The problems that an existing catalyst contains highly toxic Cr, the reaction temperature is larger than or equal to 200 DEG C, and stability is poor are solved. The prepared catalyst does not contain a toxic element Cr, piperazine and N-hydroxyethyl piperazine can be efficiently synthesized in one step, and the catalyst is good in stability, low in dosage and low in production cost.

Methods for treating Sickle Cell Disease (SCD) comprising administering a BTKi, such as at least one compound chosen from (R)-2-[3-[4-amino-3-(2-fluoro-4-phenoxy-phenyl)pyrazolo[3,4-d]pyrimidin-1-yl]piperidine-1-carbonyl]-4-methyl-4-[4-(oxetan-3-yl)piperazin-1-yl]pent-2-enenitrile (rilzabrutinib) and pharmaceutically acceptable salts thereof, are disclosed.

The invention provides an oral thylakoid product for resisting organ failure and aging, which is prepared by the following steps: extracting thylakoid from plants including spinach, arabidopsis thaliana, lettuce, cabbage, green algae or wheat seedlings, redissolving the thylakoid into a buffer salt solution A, and carrying out ultrasonic treatment for 10-20 minutes under the ultrasonic power of 200-500W to prepare a suspension; adjusting the concentration of the suspension to 0.5-2 mg / ml, and obtaining a nano capsule-like body with the particle size of 200-500 nm by using a microfluidic technology; the buffer salt solution A is prepared from 10 to 100 mmol / L of 4-hydroxyethyl piperazine ethanesulfonic acid (HEPES), 1 to 2 mmol / L of ethylenediamine tetraacetic acid (EDTA) disodium, 0.5 to 4 mmol / L of magnesium chloride (MgCl2), 1 to 10 mmol / L of ascorbic acid and 100 to 500 mmol / L of sapoeda sodium (SNAC), and the pH value of the buffer salt solution A is adjusted to 7.5 to 8.0; and the concentration of the capsule in the buffer salt solution A is 100-400 mg / mL. According to the product, self QPRT enzyme of the thylakoid is used for efficiently catalyzing de novo synthesis of NAD + of whole body tissues and organs, so that multiple physiological processes such as energy synthesis enhancement, oxidative stress reduction and inflammatory reaction relief are finally realized, organ failure is efficiently reversed, and organ aging is relieved.

The invention provides a preparation method of a nano-gold star material, which comprises the following steps: stirring and heating a chloroauric acid solution, adding a sodium citrate solution, continuously stirring and heating, when the color of the solution is changed from colorless to dark red, adjusting the rotating speed to 600rpm, turning off a heating device, cooling at room temperature, filtering the reacted solution by using a water-based filter membrane, and drying to obtain the nano-gold star material. Removing impurities to obtain a gold seed solution; characterizing the gold seed solution and the gold seed particles; the preparation method comprises the following steps: adding a 4-hydroxyethyl piperazine ethanesulfonic acid solution, a gold seed solution, a hydroxylamine solution and a magnetic rotor into deionized water, dropwise adding a 22.5 mM chloroauric acid solution, adjusting the rotating speed to 700rpm, and reacting for 15 minutes at room temperature to obtain the nano gold star material. The prepared nano gold star material is uniform, stable, adjustable in particle size and high in dispersity, the material is in a three-dimensional multi-branch shape, and the diameter of the material is adjustable within 50-200 nm.

The invention belongs to the technical field of membrane separation, and particularly relates to a polyamide composite membrane, a preparation method thereof and a water purification method. Piperazine is dissolved in deionized water, a PIP solution is prepared, and the concentration of piperazine in the PIP solution is 0.05-2 wt%; fumaryl chloride is dissolved in a first organic solvent, an FC / organic solution is prepared, and the concentration of fumaryl chloride in the FC / organic solution is 0.2 wt%; soaking a basement membrane in the PIP solution, enabling the basement membrane to fully adsorb PIP, removing a redundant water phase on the surface of the basement membrane, forming a uniform water phase environment, and obtaining the treated basement membrane; and transferring the FC / organic solution to the surface of the treated basement membrane, carrying out polymerization reaction on the FC and the PIP, washing with a second organic solvent to terminate the polymerization reaction, and drying to obtain the polyamide composite membrane. According to the preparation method, construction of the polyamide layer can be rapidly completed at normal temperature and normal pressure, controllable adjustment of the shape of the polyamide layer can be achieved, and the prepared membrane is stable in structure and good in repeatability.

The application relates to the technical field of pharmaceutical chemistry, and particularly discloses a key impurity of netupitant and a preparation method thereof. The preparation method of the key impurity of netupitant is as follows: netupitant is placed in a dichloromethane medium, stirred, heated and refluxed, and the netupitant and the dichloromethane are reacted. The structure of the netupitant contains an N-methyl piperazine ring, and a chloromethyl group is connected to a tertiary amine nitrogen of the ring. The reaction generates a chloromethylated quaternary ammonium salt, which is the key impurity of the netupitant. The impurity belongs to an impurity possibly generated in a preparation route of the netupitant. The application discloses reaction conditions for generating the key impurity of the netupitant, and provides a reference for quality control of the netupitant.

The present application relates to a kind of carbon dioxide mineralization method and carbon dioxide mineralization device.The carbon dioxide mineralization method includes the following steps: mixing absorption liquid and industrial solid waste at room temperature, obtain mortar;Make mortar solid-liquid separation, obtain clear liquid and thick slurry;Carbon dioxide in flue gas is absorbed by clear liquid, obtain carbon-rich absorption liquid;Carbon-rich absorption liquid and thick slurry occur mineralization reaction at 180 DEG C-220 DEG C, obtain mineralized slurry;Make mineralized slurry solid-liquid separation, obtain mineralized ash and mineralized clear liquid;Wherein, absorption liquid includes inorganic base and organic base, organic base includes monoethanolamine, diethanolamine, triethanolamine, 3-methylaminopropylamine, N-methyl diethanolamine, piperazine, diethylene triamine, triethylene tetramine, tetraethylene pentamine and 2-amino-2-methyl-1-propanolamine at least two kinds.The method greatly improves CO2 capture rate and CO2 utilization rate, and organic base consumption is less, absorption liquid regeneration energy consumption is low, and overall economy is good.

This invention discloses a method for synthesizing a venetum intermediate, specifically as follows: Step 1: In an organic solvent, 2,4-difluorobenzoic acid and 5-hydroxy-7-azaindole undergo an etherification reaction under the action of an acid-binding agent. After the reaction, post-treatment yields 2-((1h-pyrrolo[2,3-b]pyridin-5-yl)oxy)-4-fluorobenzoic acid; Step 2: 2-((1h-pyrrolo[2,3-b]pyridin-5-yl)oxy)-4-fluorobenzoic acid reacts with 1-((2-(4-chlorophenyl)-4,4-dimethylcyclohexene-1-)methyl)piperazine in… An amination reaction occurs under the action of a base. After the reaction, post-treatment yields 2-(7-azaindole-5-oxy)-4-(4-((2-(4-chlorophenyl)-4,4-dimethylcyclohexene-1-)methyl)piperazine-1-)benzoic acid, i.e., Venetantora intermediate III. The synthetic process provided by this invention avoids Grignard reactions and subsequent hydrolysis reactions, shortens the operation steps, simplifies the synthetic process, and provides a simple and easy-to-operate synthetic process. The raw materials are inexpensive and readily available, while avoiding the use of highly toxic raw materials. The production process is green and environmentally friendly, and suitable for industrial production.

This invention provides a simple synthesis method for Fe-Ag / CMP nanopolymers with catalase-like activity and their application in hydrogen peroxide detection, belonging to the field of bioanalytical technology. The method of this invention includes the following steps: (1) preparing a 4-hydroxyethylpiperazine thiosulfonic acid (HEPES) standard buffer solution; (2) adding cytidine monophosphate (CMP) to the solution obtained in step (1) and stirring until the CMP is fully dissolved. Then, under vigorous stirring, ferric nitrate aqueous solution and silver nitrate aqueous solution are added sequentially, at which point the colorless solution turns pale yellow; (3) transferring the mixed solution obtained in step (2) to a centrifuge tube, centrifuging at 12000 rpm for 8 min to collect the precipitate, washing it three times with distilled water, and finally adding 4 mL of distilled water to obtain a 1 mg / mL Fe-Ag / CMP suspension. This invention utilizes CMP as a biological ligand and Ag... + Fe 3+ Simultaneous coordination, and the reducing amino groups on CMP can directly transfer Ag... + In situ reduction to silver nanoparticles (AgNPs) led to the one-step synthesis of a bimetallic Fe-Ag / CMP nanopolymer with hydrogen peroxide-like nanozyme activity, enabling the detection of hydrogen peroxide.

The present application relates to a kind of five-ring thiazole indole ketone piperazine amide derivatives and purposes thereof.The derivatives take ethyl cyanoacetate as starting material, generate hydroxylamine compound (A) under the action of sodium nitrite and phosphoric acid;Obtain 2-amino ethyl cyanoacetate (B) by reduction, in turn with acetic anhydride, lawson reagent is reacted, and 5-amino-4-carboxylate thiazole compound (D) is obtained;After bromination by NBS, under the catalysis of phosphorus oxychloride, react with tetrahydropyridine indole ketone, generate 2-bromo-6,7-dihydrothiazolo [5'',4'':4',5'] pyrimido [1',2':1,2] pyrindo [3,4-b] indole-4 (12H) -ketone (F), again under alkaline condition, first with Boc piperazine, then by Boc treatment and obtain compound (H);Finally, react with acyl chloride, and 28 different substitution structures of five-ring thiazole indole ketone piperazine amide compound (I1-I28) are synthesized.The 28 compounds are tested on three kinds of cancer cells, and the results show that: 28 compounds have significant inhibitory activity on Hela cervical cancer cells, HT-29 human colon cancer cells and HGC-27 human gastric cancer cells.

The application discloses a kind of ultraviolet absorber with triazine ring as main structure and its preparation method and its application in aramid fiber, the ultraviolet absorber has the following structural formula: Wherein, R1, R2, R3, R4 It is the group containing phenyl or substituted phenyl, R5 It is piperidyl, piperazyl, pyrrolidinyl and one of the following structures:This ultraviolet absorber has good absorption to UVA-UVB band ultraviolet, especially in 290~320 nm range has good ultraviolet absorption, adding the ultraviolet absorber in aramid fiber can significantly improve its weather resistance and service life, keep mechanical property, delay ultraviolet degradation, reduce the direct damage of fiber.

The invention discloses a preparation method of an ultrathin and super-hydrophilic polyamide-polyester composite nanofiltration membrane. According to the method, on the basis of a nano-scale sodium-based cyclodextrin metal-organic framework (U-Na-beta-CD-MOF) synthesized by a green ultrasonic strategy, accurate regulation and control on the structure and performance of a polyamide active layer are realized by regulating and controlling the diffusion behavior of a piperazine (PIP) monomer in an interfacial polymerization process. The preparation method comprises the following steps: S1, contacting a pretreated polyester porous support membrane with a water-phase solution, standing, enabling the water-phase solution to fully infiltrate the surface of the support membrane, and then removing redundant water-phase solution; s2, contacting the support membrane from which the water phase solution is removed in the step S1 with an organic phase solution under a low-temperature condition, standing, carrying out interfacial polymerization reaction, and removing the organic phase solution to form a polyamide active layer; and S3, cleaning the composite membrane obtained in the step S2, and carrying out curing or quenching treatment to obtain the ultrathin and super-hydrophilic polyamide-polyester composite nanofiltration membrane with the nano wrinkle structure. The water phase solution is a mixed solution of piperazine, sodium carbonate and a nanoscale sodium-based beta-cyclodextrin metal-organic framework; the invention provides an efficient, simple and controllable nanofiltration membrane preparation strategy, is suitable for efficient separation of pollutants and ions, and has a good application prospect.

The invention relates to application of 1-allyl piperazine or pharmaceutically acceptable salt thereof in preparation of a medicine for treating Parkinson's disease. A caenorhabditis elegans PD model is adopted to prove for the first time that on one hand, 1-allyl piperazine can obviously enhance autophagy activity in a model animal body, efficiently promote removal of aggregation alpha-synuclein and radically relieve damage of Parkinson's disease characteristic pathological protein deposition to neurons, and on the other hand, 1-allyl piperazine can effectively promote removal of aggregation alpha-synuclein and radically relieve damage of Parkinson's disease characteristic pathological protein deposition to neurons. The compound can effectively activate mitochondrial unfolded protein reaction. The autophagy activation pathway and the mitochondrial function regulation pathway can generate a synergistic effect to jointly relieve the neurodegeneration process related to the Parkinson's disease, so that dopaminergic neurons are protected, and the pathological progress of the disease is delayed.

The invention discloses a preparation method of a water-resistant and melting-resistant sodium silicate-based fireproof coating, and belongs to the technical field of preparation of fireproof materials and inorganic-organic hybrid coatings. The method comprises the following steps: (1) reacting isophorone diisocyanate with polypropylene glycol to prepare an isocyanate-terminated polyurethane prepolymer; (2) mixing the polyurethane prepolymer with piperazine pyrophosphate to obtain a component A; (3) mixing a sodium silicate aqueous solution with melamine to obtain a component B; and (4) mixing and curing the component A and the component B in proportion to obtain the coating. According to the invention, an isocyanate group in a polyurethane prepolymer and a sodium silicate aqueous solution are subjected to an in-situ chemical reaction, an organic hydrophobic network is constructed on the surface of an inorganic phase, and the water resistance of the coating is remarkably improved. Meanwhile, piperazine pyrophosphate and melamine form an intumescent flame-retardant system, the intumescent flame-retardant system and sodium silicate are synergistically promoted to form a compact and stable intumescent layer at high temperature, and the problems that a traditional water glass coating easily absorbs moisture and melts and flows at high temperature are effectively solved. The method is simple and controllable in process, and the prepared coating has excellent water resistance, fire resistance and heat insulation performance.

The invention discloses an anti-oxidation, whitening and brightening composition as well as a preparation method and application thereof. The anti-oxidation, whitening and brightening composition is prepared from the following components in parts by weight: 2 to 6 parts of nicotinamide, 0.5 to 5 parts of tranexamic acid, 1 to 5 parts of nonapeptide-1 solution, 0.5 to 1 part of tetrahydromethylpyrimidine carboxylic acid, 0.5 to 2 parts of pink red plum compound essence, 0.01 to 0.5 part of hydroxyethyl piperazine ethanesulfonic acid, 0.01 to 0.5 part of glabridin and 0.0001 to 0.2 part of glutathione. According to the invention, the composition prepared from nicotinamide, tranexamic acid, nonapeptide-1, tetrahydromethylpyrimidine carboxylic acid, pink-red plum composite essence, hydroxyethyl piperazine ethanesulfonic acid, glabridin and glutathione is prepared into the essence, and the clearance rate of the essence to ABTS free radicals reaches 58% or above, which shows that the essence has very good antioxidant ability; the cell tyrosinase activity inhibition rate of the composition under the concentration of 1.2% (v / v) reaches 51% or above, which shows that the composition has very good whitening and brightening effects.

This application relates to a rifapentine-containing pharmaceutical composition and its preparation method. The rifapentine-containing granules are prepared by dry granulation, which reduces the content of impurities present in existing pharmaceutical compositions, especially the content of the genotoxic impurity 1-cyclopentan-4-nitrosopiperazine, thereby improving the safety and efficacy of the drug.

The invention discloses a (-)-menthol group-containing nicotinamide derivative with antifungal activity as well as a preparation method and application thereof, and relates to the technical field of synthesis of agricultural chemicals. The derivative has a structure as shown in a general formula (I), in the formula, n is an integer from 1 to 5, and R1, R2, R3 and R4 are specific substituent groups. Through a molecular hybridization strategy, the (-)-menthol, the N-fatty acyl piperazine bridge and the nicotinamide fragment are covalently linked, and a compound with a brand new structure is created. A biological activity test shows that the series of compounds have remarkable inhibitory activity on various plant pathogenic fungi, especially sclerotinia sclerotiorum and valsa mali of apple trees, and are low in cytotoxicity. Molecular docking research proves that the action target of the gene is succinate dehydrogenase (SDH). The invention provides a valuable leading structure for developing novel SDHI bactericides.

Provided herein are methods for preparing crystalline forms of (R)-5-carbamoylpyridin-3-yl-2-methyl-4-(3-(trifluoromethoxy)benzyl)piperazine-1-carboxylate.

The invention provides a method for continuously and efficiently synthesizing 2, 6-diamino piperazine-1-oxide, which comprises the following steps: S1, preparing an N-nitroso iminodiacetonitrile solution at room temperature, and stirring and dissolving for 5 minutes; s2, sequentially adding hydroxylamine salt and alkali into a solvent, stirring at room temperature for 10-15 minutes for pre-dissolving, adding a proper amount of metal salt catalyst into the obtained solution, and continuously stirring for 5-10 minutes; s3, exhausting the continuous tubular reactor by using a hydroxylamine solution until the continuous tubular reactor is full of the solution; s4, feeding the N-nitrosoiminodiacetonitrile solution and the hydroxylamine solution into a continuous tubular reactor through a mixer according to a certain proportion by adopting a delivery pump, and optimizing the flow velocity and temperature of the reaction solution and the pressure in the continuous tubular reactor; and S5, enabling the reaction liquid to flow out from an outlet of the continuous tubular reactor, performing suction filtration, washing a filter cake with an alcoholic solution, and drying. The method can obviously improve the reaction rate, reduce the generation of impurities and improve the production efficiency.

The invention discloses a diketopiperazine heterodimer as well as a biosynthesis method and application thereof, and belongs to the technical field of bioengineering. The biosynthesis method of the diketopiperazine heterodimer comprises the following steps: S1, culturing a recombinant cell containing P450 dimerization enzyme or a mutant thereof, and performing induced expression to obtain a whole-cell culture; and S2, adding a cyclic dipeptide substrate containing tryptophan into the whole-cell culture, carrying out a catalytic reaction, and separating and purifying the obtained product to obtain the diketopiperazine heterodimer. According to the invention, the P450 dimerization enzyme or the mutant thereof is used for catalyzing the biosynthesis of the tryptophan-containing diketopiperazine into the diketopiperazine heterodimer with different regioselectivity / stereoselectivity, the biosynthesis method is green and environment-friendly, the efficiency is high, and the variety of the diketopiperazine heterodimer is greatly expanded.