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33 results about "Hemiacetal" patented technology

A hemiacetal or a hemiketal is a compound that results from the addition of an alcohol to an aldehyde or a ketone, respectively. The Greek word hèmi, meaning half(semi), refers to the fact that a single alcohol has been added to the carbonyl group, in contrast to acetals or ketals, which are formed when a second alkoxy group has been added to the structure.

Bicyclic hemiketal structure compound and preparation method thereof

PendingCN120923459AOrganic chemistry methodsBlood disorderPtru catalystReaction sequence
The invention discloses a compound containing a bicyclic hemiketal structure and a preparation method thereof, alkynyl allyl carbonate is used as a raw material, in the presence of a nucleophilic catalyst, alkynyl allyl carbonate reacts with a benzoylacetonitrile derivative, ABB'multi-component reaction is carried out through a continuous [5 + 1] / addition / cyclization reaction sequence, and the compound containing the bicyclic hemiketal structure is obtained. Bicyclic hemiketal derivatives commonly seen in natural product structures are obtained with good to excellent diastereoselectivity. The method has the advantages of good diastereoselectivity products, excellent chemical selectivity, greenness, mild reaction conditions, convenience in operation, few byproducts and the like, the synthesis steps are good in economy, and four chemical bonds and three continuous chiral centers are simultaneously constructed through one-step operation. Meanwhile, the compound with the bicyclic hemiketal structure has important application value in multiple fields of medicinal chemistry, natural product chemistry, traditional Chinese medicine chemistry and the like, and an efficient preparation means and a series of candidate compounds are provided for development of functionality or biological activity of related compounds with the bicyclic hemiketal / hemiacetal structure.
Owner:HEFEI JIUYI AGRI DEV

Stereoselective complementary alcohol dehydrogenase mutant and application thereof

The invention relates to the technical field of biological engineering and biological catalysis, in particular to two alcohol dehydrogenase mutants and application thereof. The invention discloses a pair of alcohol dehydrogenase mutants CpAR2-M3 (F85A / F192L / E209A) and CcPAR-M1 (V158L) with opposite stereoselectivity, wherein the corresponding amino acid sequences of the alcohol dehydrogenase mutants CpAR2-M3 (F85A / F192L / E209A) and CcPAR-M1 (V158L) are respectively shown as SEQ ID No.5 and SEQ ID No.6. The invention further discloses a preparation method of the alcohol dehydrogenase mutants. The method can be applied to asymmetric reduction of hemiacetal compounds, synthesis of corresponding key intermediate axial chiral biaryl benzyl alcohol compounds with complementary stereoselectivity is achieved, the highest yield can reach 95%, the highest stereoselectivity can reach 99% e.e., and the method is suitable for industrial production. A green, efficient and high-stereoselectivity synthesis strategy is provided for subsequent enantiocomplementary synthesis of the compounds.
Owner:NANJING TECH UNIV

Biocatalytic synthesis of esters

PCT designated stageWO2026104942A1OxidoreductasesFermentationRedox enzymesHemiacetal
The present invention relates to a biocatalytic synthesis of esters that can also be implemented on an industrial scale. In particular, the invention relates to a process for the production of esters, via a hemiacetal intermediate, consisting of the following steps: – a step of bringing into contact, in a reaction medium, • a mixture of a C1– Cn alcohol and a C1– Cn aldehyde with an enzymatic catalytic system comprising an oxidized cofactor selected from NAD(P)+ and NAD+ and a polypeptide of the oxidoreductase group having preferential dehydrogenase activity toward the formed hemiacetal and the starting aldehyde, or alternatively • a C1– Cn alcohol with an enzymatic catalytic system comprising an oxidized cofactor selected from NAD(P)+ and NAD+ and a polypeptide of the oxidoreductase group having preferential dehydrogenase activity toward the formed hemiacetal, the starting alcohol, and the formed aldehyde, or alternatively • a C1– Cn aldehyde with an enzymatic catalytic system comprising a reduced cofactor selected from NAD(P)H or NADH and a polypeptide of the oxidoreductase group having preferential dehydrogenase activity toward the starting aldehyde and the formed hemiacetal, where n may be any number, and – a step of isolating the corresponding ester.
Owner:SOFT CHEM SRL +1

Preparation method and application of metabolism programming hydrogel

The invention belongs to the technical field of hydrogel preparation, and relates to a preparation method and application of metabolism programming hydrogel, and the preparation method comprises the following steps: 1, oxidizing dextran Dex through sodium periodate NaIO4 to generate oxidized dextran ODex rich in aldehyde; 2, under the protection of nitrogen, carrying out amino dynamic Schiff base reaction of APTC and carrying out covalent binding with an aldehyde group of oxidized dextran ODex to form ODex-APTC; 3, mixing ODex-APTCC and CMC GOx solutions at room temperature to form hydrogel based on hemiacetal crosslinking and a hydrogen bond mechanism; according to the invention, autonomous'antibacterial repair 'dual-phase switching is realized through metabolic microenvironment reprogramming; in the stage of wound surface high-glucose infection, the hydrogel utilizes a diabetes wound surface high-glucose environment as an endogenous fuel, and glucose reduction, active oxygen mediated sterilization and microenvironment acidification are realized at the same time through reaction of glucose oxidase and glucose; when glucose oxidase reacts, the acid environment triggers a controlled H2S release program, and wound healing is accelerated by relieving oxidative stress and activating a regeneration signal channel.
Owner:SECOND AFFILIATED HOSPITAL OF COLLEGE OF MEDICINEOF XIAN JIAOTONG UNIV

A MALDI reaction-type matrix for analyzing reducing sugars, 5-methoxy-2-hydroxybenzhydrazide

PendingCN122385739ABenzoic hydrazideBenzoic acid
This application relates to a MALDI reactive matrix, 5-methoxy-2-hydroxybenzoyl hydrazine, for the analysis of reducing sugars, belonging to the field of sugar biochemical analysis technology. This application provides the application of 5-methoxy-2-hydroxybenzoyl hydrazine as a MALDI reactive matrix in combination with 2,5-dihydroxybenzoic acid in the analysis of reducing sugars. Specifically, 5-methoxy-2-hydroxybenzoyl hydrazine is the reactive matrix, possessing a hydrazine reactive group that can react with the hemiacetal terminus of reducing sugars. 2,5-dihydroxybenzoic acid acts as a catalyst, significantly promoting the efficient reaction between 5-methoxy-2-hydroxybenzoyl hydrazine and reducing sugars. The 5-methoxy-2-hydroxybenzoyl hydrazine / 2,5-dihydroxybenzoic acid composite matrix provided in this application can form a uniform co-crystallization with reducing sugars, exhibiting good signal reproducibility (RSD < 10%) and good linearity in the range of 0.2~20 pmol / μL (R0). 2 > 0.999).
Owner:ZHEJIANG UNIV

Method for introducing silica nanoparticles to reduce H2S in liquid or gas streams

1. A method for reducing the amount of HS in a liquid or gas stream, the method comprising: a) operating an industrial process having HS in a liquid or gas stream, or in both the liquid and gas streams associated with the industrial process, the industrial process comprising connecting pipes that allow liquids and gases to move from one location to another within the process; b) injecting a silica nanoparticle mixture into a liquid or gas stream, or in both the liquid and gas streams associated with the industrial process, the silica nanoparticle mixture being in a colloidal or dry state; and c) providing a material in the silica nanoparticle mixture to react with the HS to result in a reduction of HS in the liquid or gas product fluid. In certain embodiments, the silica nanoparticle mixture comprises silica nanoparticles, with or without a surface treatment, and one or more chemicals selected from the group consisting of triazines, alcohols, polyols, ketones, aldehydes, and hemiacetals.
Owner:NISSAN CHEMICAL AMERICA CORP

Full-temperature-range liquid phase temperature swing adsorption process for deep dehydration and impurity removal of trioxymethylene

The invention discloses a full-temperature-range liquid phase temperature swing adsorption process for deep dehydration and impurity removal of trioxymethylene, which mainly comprises the following steps: raw material flow, temperature swing adsorption purification, temperature swing adsorption desorption and rectification concentration. The method comprises the following steps: purifying trioxymethylene which is obtained or purchased in a trioxymethylene production process and has the purity of 99.9%, the water content of 500-1000ppm, the content of micromolecular impurity components such as formaldehyde / methanol of 100-300ppm and the content of macromolecular impurity components such as hemiacetal and paraformaldehyde of more than or equal to 50ppm until the purity of the trioxymethylene is more than or equal to 99.999%, the water content of the trioxymethylene is less than or equal to 20-50ppm, and the water content of the trioxymethylene is less than or equal to 20-50ppm; the content of micromolecular impurity components such as formaldehyde and methanol is smaller than or equal to 20-50 ppm, the content of macromolecular impurity components such as methylal and paraformaldehyde is smaller than 20-50 ppm, the problems that the purity of products obtained through existing methods such as special rectification and membrane separation does not reach the standard, and production energy consumption and cost are high are solved, the process is simple, import is replaced, and the method is suitable for industrial production. And the quality requirement of polymer-grade trioxymethylene required by polyformaldehyde production is met.
Owner:SICHUAN TECHAIRS

Temperature difference MMA fixed bed anti-blocking method and device

The invention discloses a temperature difference MMA fixed bed anti-blocking method and a temperature difference MMA fixed bed anti-blocking device. In the method and the device, at least one section of heating belt and a pressure gauge are arranged on a pipeline at the front end of a feed port of an MMA fixed bed reactor. In a liquid raw material for preparing MMA through condensation of methyl propionate and formaldehyde, methanol and formaldehyde form hemiacetal, and methanol is excessive. Hemiacetal is decomposed when the temperature reaches a certain temperature, released formaldehyde is self-polymerized to form a plugging block, and the plugging block is gradually dissolved by newly entering methanol gas to form hemiacetal to enter. According to the method and the device provided by the invention, the temperature of the heating belt is dynamically adjusted, and the precipitation position of the polyformaldehyde is changed by dynamically adjusting the precipitation-redissolution process, so that the pipeline is prevented from being blocked. According to the method and the device, the anti-blocking effect is remarkable, the operation time of the reactor is prolonged to 650-1770 hours, and high reaction performance can be maintained; the problem of pressure rise can be solved on line without stopping by adjusting the heating belt or the cold tracing device in a segmented mode, and production energy consumption and cost are reduced.
Owner:BEIJING RISUN TECH CO LTD

A multi-substituted tetrahydrofuran and tetrahydropyran diene compound and its preparation method

The present invention belongs to the field of organic synthesis and provides a polysubstituted tetrahydrofuran and tetrahydropyran dienophile compound represented by formula I, wherein R 1 is selected from aryl or heteroaryl; R 2 and R 3 are each independently selected from hydrogen or C1-C6 alkyl; R 4 and R 5 are each independently selected from aryl, heteroaryl, C1-C6 alkyl or hydrogen; R 6 and R 7 are selected from cyano, nitro, C1-C6 alkyl, ester group or hydrogen. The target product of the present invention is synthesized through two steps, and the steps are as follows: (1) α-alkenyl lactone reacts with a nucleophile (such as nitrile, nitroalkane or ester, etc.) under the action of a base at -78 to 60 °C for 1-48 h to obtain a hemiacetal intermediate. (2) The hemiacetal intermediate is dehydrated under the catalysis of a Lewis acid or a Bronsted acid to form the compound represented by formula I. This method has simple process equipment, easy operation, is environmentally friendly, has low cost and good yield.
Owner:CHENGDU ORGANIC CHEM CO LTD CHINESE ACAD OF SCI

Cosmetic

PendingJP2025090081ACosmetic preparationsBody powdersHemiacetalPhosphate
To provide a cosmetic that exhibits superior rust prevention effect on aluminum even under high-temperature storage conditions.SOLUTION: A cosmetic has a liquid composition stored in an aluminum-containing container, the liquid composition comprising: (A) a disaccharide having a hemiacetal structure; and (B) one or more selected from the group consisting of aminocarboxylic acid-based chelating agents, phosphonic acid-based chelating agents, and phosphate-based chelating agents, in which the mass ratio [(A) / (B)] of the component (A) content to the component (B) content is 1.5 or more and 5 or less.SELECTED DRAWING: None
Owner:LION CORP

Metal alkoxide-containing composition

PendingJP2026109092AVinyl etherHemiacetal
For example, when used as a material for forming metal oxide thin films, the objective is to provide a metal alkoxide-containing composition that can form metal oxide thin films with fewer cracks and lower surface roughness compared to conventional thin films, even when the thickness is increased. [Solution] A metal alkoxide-containing composition comprising the following component (A) and the following component (B), wherein the mass-based content ratio (A / B) is 70.0 / 30.0 to 99.9 / 0.1. (A) Metal alkoxides with a total of 1 to 40 carbon atoms, (B) A hemiacetal ester of a carboxylic acid consisting of a 1-4 valent carboxylic acid and a vinyl ether, wherein the number of carbon atoms after removing the vinyl group of the vinyl ether is 1-6.
Owner:NOF CORP

Veterinary drug doxycycline composition and preparation process thereof

The invention belongs to the technical field of doxycycline, and particularly relates to a veterinary drug doxycycline composition and a preparation process thereof, the veterinary drug doxycycline composition comprises 24%-26% of methanol, 3.5%-6.5% of oxytetracycline base, 0.03%-0.1% of methanol ammonia, 1.7%-3.2% of NBS, 24%-26% of 11 alpha-bromine-6, 12-hemiketal oxytetracycline, 7%-8% of HZSM-5, 24%-26% of toluenesulfonic acid and 3%-4% of palladium on carbon, the veterinary drug doxycycline composition further comprises catalysts, the catalysts comprise 2.7%-3.2% of titanium tetraisopropylate and 3.07%-4% of S-diphenol, and the reaction temperature is controlled to be 30-50 DEG C; the preparation method comprises the following steps: sequentially putting 100g of methanol, 10g of oxytetracycline base and 0.1 g of methanol ammonia into a reaction bottle, stirring for 30 minutes in an environment of 20-30 DEG C by using an ultrasonic stirrer, starting to cool to-10 to-15 DEG C, adding 5g of dried and crushed NBS, and carrying out dechlorination and asymmetric hydrogenation by using a self-made palladium-carbon catalyst, so that the yield and the chemical and stereoselectivity of the reaction are remarkably improved, the total yield reaches 53%, and the yield is up to 90%. The method has the advantages of high yield, good product quality and the like, and the doxycycline primary liquid is heated by heating equipment and lasts for a fixed time, so that the drug property of the doxycycline primary liquid is enhanced at a specific temperature, and the adverse reaction of drugs to animals is reduced.
Owner:HENAN JINHUA AGRI ANIMAL PHARM CO LTD

A method for selectively synthesizing an empagliflozin intermediate

The present invention discloses a method for selectively synthesizing an empagliflozin intermediate. By selectively hydrogenating and reducing gluconolactone to chiral hemiacetal, and then directly performing a dehydroxy arylation coupling reaction with an aryl halide compound under the action of a catalyst to obtain an intermediate compound Ⅳ of empagliflozin. The beneficial effects of the present invention are as follows: Through the selective synthesis of chiral hemiacetal and the direct dehydroxy arylation coupling reaction, the selectivity of the gluconolactone connection reaction is effectively increased, the reaction steps of the overall route are reduced, and the generation of reaction by-products can be effectively reduced; in addition, the synthesis method of the present invention is simple to operate, the product is easy to process, the product yield and purity are relatively high, the raw materials are easily available, and it is suitable for industrial scale-up production.
Owner:JIANGSU ALPHA PHARM CO LTD

Application of 2,4-dicarboxyphenylhydrazine as a reactive matrix for mass calibration and N-glycan analysis in negative ion mode of MALDI mass spectrometry

The present invention discloses an application of a reactive matrix 2,4-dicarboxyphenylhydrazine in mass calibration and N-glycan analysis in the negative ion mode of a MALDI mass spectrometer. 2,4-dicarboxyphenylhydrazine reacts with the hemiacetal at the end of a reducing sugar to form a hydrazone. The reaction has high derivatization efficiency and utilizes a target plate for online derivatization, which is simple to operate. Utilizing this derivatization strategy, derivatized products can be detected in the negative ion mode. The carboxylate groups in 2,4-dicarboxyphenylhydrazine significantly improve the ionization efficiency of reducing sugars in the negative ion mode. The present invention uses dextran derivatized with 2,4-dicarboxyphenylhydrazine as a mass calibrant for a MALDI mass spectrometer. The mass difference between adjacent signal peaks is 162Da, corresponding to one glucose residue, thereby achieving precise calibration in the negative ion mode simultaneously. In addition, the DCPH / DHB composite matrix can significantly improve the cocrystallization uniformity with the analyte and improve the accuracy of quantitative detection of N-glycans.
Owner:ZHEJIANG UNIV

Process for the preparation of chiral octalide hemiacetal compounds and their reaction with ibuprofen drug molecules

PendingCN122127305AOrganic chemistryHemiacetalCarboxyl radical
This application discloses a method for preparing a chiral eight-membered ring hemiacetal compound and its reaction with ibuprofen drug molecules, wherein the eight-membered ring compound is shown in any of 1)-4): 1) (5S,7R,12R)-12-oxo-7-(2-oxopropyl)-5H,7H-dibenzo[c,f][1,5]oxothiazine-5-yl acetate; 2) (5S,7R,12R)-3,9-dichloro-12-oxo-7-(2-oxopropyl)-5H,7H-dibenzo[c,f][1,5]oxothiazine-5-yl acetate; 3) (5S,7R,12R)-12-oxo-7-(2-oxohexyl)-5H,7H-dibenzo[c,f][1,5]oxothiazine-5-yl acetate. The invention also discloses a method for preparing this eight-membered ring hemiacetal. The eight-membered ring hemiacetal of the present invention can react with carboxyl-containing drug molecules (ibuprofen), thus serving as a lead drug molecule.
Owner:GUANGXI UNIV FOR NATITIES +2

An apparatus and method for producing a hemiacetal

The application discloses a production device and a production method of a condensation alcohol, wherein ethylene glycol is subjected to six units of a condensation reaction, separation and refining, esterification reaction, esterification separation, hydrolysis reaction and hydrolysis separation, so that the production and refining of diethylene glycol prepared by dehydration and condensation of ethylene glycol are realized, the process conversion rate is improved through by-product treatment, and the separation difficulty is reduced. The production process disclosed by the application is continuous and easy to operate, and has industrial feasibility.
Owner:DALIAN INSTITUTE OF CHEMICAL PHYSICS CHINESE ACADEMY OF SCIENCES

Crosslinkable flame-retardant coating composition

The invention is directed to a crosslinkable flame-retardant coating composition comprising the following components:a) a dendritic polymer having hydroxyl groups, wherein the dendritic polymer has a hydroxyl number in the range of 80 to 800,b) a polyol having at least 3 hydroxyl groups,c) an ammonium polyphosphate compound,d) a base coat polymer selected from a polycarbamate resin or a polymer bearing carboxyl groups, ande) a crosslinker for crosslinking the base coat polymer selected from a compound having two or more aldehyde groups, acetals or hemiacetals of the aldehydes, or a polycarbodiimide.Such a cross-linkable flame-retardant coating composition improves the overall appearance of the cross-linked base coating on a substrate and also imparts improved flame-retardancy.
Owner:SWIMC LLC

Process for preparation of alkyl methacrylate

There is provided a process for preparing an alkyl methacrylate, the process comprising reacting methacrolein with an alkyl alcohol in an oxidative esterification reaction (OER) system in the presence of at least one inhibitor, an oxygen-containing gas, and a noble metal-containing catalyst to produce an OER product stream, the OER product stream comprises alkyl methacrylate, alkyl isobutyrate in an amount in the range of 0.1 ppm to 5000 ppm based on the total weight of the OER product stream, and at least one Michael addition product in an amount in the range of 0.01 wt% to 5 wt% based on the total weight of the OER product stream. The OER product stream is fed to an alcohol recovery distillation column to provide an overhead stream comprising alkyl alcohol and methacrolein and a bottoms stream comprising alkyl methacrylate, alkyl isobutyrate, acetal and / or hemiacetal of methacrolein. The bottoms stream of the alcohol recovery distillation column is fed to an acetal hydrolysis reactor and a phase separator.
Owner:DOW GLOBAL TECHNOLOGIES LLC +1

Aqueous resin composition and use as binder in fibre-based products

ActiveUS12415870B2FiberHemiacetal
The invention relates to an aqueous resin composition and a method for the manufacture of an aqueous resin composition which resin is a reaction product of an oxidised polysaccharide and a crosslinking agent, which oxidised polysaccharide is an oxidised cellulose comprising aldehyde groups, which crosslinking agent comprises two or more groups reactive with the aldehyde groups, wherein the aldehyde groups in the resin in the aqueous resin composition are in hydrated or un-hydrated form and are at least partly converted to inter- or intramolecular hemiacetals, wherein the resin is dispersed and / or dissolved but not gelled. The invention also relates to the use of this composition for a binder in inorganic fibres products.
Owner:KREMSCHEM AUSTRIA GMBH

A benzazepine bridged ring derivative and a method for preparing the same

The application relates to the technical field of pharmaceutical chemistry, and discloses a benzazepine bridged ring derivative and a preparation method thereof. The preparation method comprises the following steps: adding a substrate (1.0 eq), a sulfur-substituted benzylpropyl aldehyde (1.5 eq), a base DABCO (0.2 eq) and dry acetonitrile (2.0 mL) into a reaction test tube, mixing the mixture at normal temperature for 24 hours, concentrating and purifying after the reaction is completed to obtain a hemiacetal product 3. Then the hemiacetal product, chloroform (0.5 mL) and H2O (100 muL) are added into the reaction test tube, and stirring is carried out at 60 DEG C for 72 hours. The reaction is monitored to be completed through thin layer chromatography, then the reaction mixture is directly purified through column chromatography to obtain a corresponding target product. The preparation method has the advantages of simple operation, mild reaction and high yield. The derivative provided by the application has good antibacterial activity, and has a wide market application prospect.
Owner:CHENGDU UNIV

Prime coat composition for optical film as well as preparation method and application of prime coat composition

The present invention relates to an undercoat composition for an optical film and a method for preparing the same. The composition comprises the following components in parts by weight: 85-95 parts of double-bond modified waterborne polyurethane with the solid content of 30%, 2-10 parts of a crosslinking agent containing silicon-hydrogen bonds and 1-5 parts of a platinum catalyst. The double-bond modified waterborne polyurethane is prepared by carrying out pH regulation, mixing and heating reaction on an aldehyde solution obtained by hydrolyzing an acetal or hemiacetal compound and a waterborne polyurethane emulsion, and carrying out post-treatment to remove small-molecule byproducts, so as to obtain the high-solid-content modified emulsion. The priming coat working solution is coated on the surface of a PET base material, and after drying and thermocuring, a compact cross-linked structure is formed through a hydrosilylation reaction. According to the invention, the adhesive force between the PET substrate and the acrylate optical resin layer is effectively enhanced, the problem that the original interface is insufficient in bonding force and easy to layer is solved, meanwhile, the process is simple and convenient, the raw material source is wide, and the method is suitable for a brightness enhancement film product for display.
Owner:上交大苏州创新院

Porous carbon material as well as preparation method and application thereof

The embodiment of the invention relates to a porous carbon material as well as a preparation method and application thereof, and the preparation method comprises the following steps: dissolving a phenol source in an anhydrous polar solution, adding cyclic organosiloxane with a preset size, and stirring, so that the phenol source and the cyclic organosiloxane are uniformly mixed to obtain a first mixed solution; adding organic alkali into the first mixed solution to enable the first mixed solution to be alkalescent, then adding an aldehyde source, and stirring to enable hydroxyl of the phenol source and carbonyl carbon of the aldehyde source to be subjected to an addition reaction to generate hemiacetal; carrying out heat treatment on the hemiacetal to enable the hemiacetal to be subjected to condensation reaction, and then washing and drying to obtain an organic silicon / phenolic resin compound; carrying out carbonization treatment on the organic silicon / phenolic resin compound in an inert atmosphere to generate a carbonized product; washing the carbonized product to remove silicon oxide in the carbonized product to form a pore structure, and then passivating to obtain the porous carbon material.
Owner:LIYANG TIANMU PILOT BATTERY MATERIAL TECH CO LTD

Process for preparing alkyl methacrylates

A process for preparing alkyl methacrylate is provided, comprising reacting methacrolein with an alkyl alcohol in an oxidative esterification (OER) system in the presence of at least one inhibitor, an oxygen-containing gas, and a noble metal-containing catalyst to produce an OER product stream, wherein the OER product stream comprises alkyl methacrylate, alkyl isobutyrate in an amount ranging from 0.1 to 5000 ppm, and at least one Michael addition product in an amount ranging from 0.01 to 5 wt %, based on the total weight of the OER product stream. The OER product stream is fed to an alcohol recovery distillation column to provide an overhead stream comprising the alkyl alcohol and methacrolein, and a bottoms stream comprising the alkyl methacrylate, alkyl isobutyrate, and acetals and / or hemiacetals of methacrolein. The bottoms stream from the alcohol recovery distillation column is fed to an acetal hydrolysis reactor and a phase separator.
Owner:DOW GLOBAL TECHNOLOGIES LLC +1

A dual amino acid-genipin derivative, its preparation method and application

The present invention discloses a bis - amino acid - genipin derivative, its preparation method and application; aiming to provide a bis - amino acid - genipin derivative with neuroprotective activity; the hemiacetal at the C - 1 position of genipin is oxidized and aminated to introduce the first amino acid fragment, and the second amino acid is introduced by esterification at the C - 10 position to obtain a series of brand - new genipin derivatives, which show good neuroprotective activity in the OGD / R - induced HT22 nerve cell injury model and can be used for preparing neuroprotective drugs; the general structural formula of the bis - amino acid - genipin derivative is as follows; it relates to the fields of pharmaceutical technology and medicinal chemistry.
Owner:GUANGDONG UNIV OF TECH

A SABRE hyperpolarization method for enhancing the signals of labile hydrogens based on dynamic covalent bond exchange

The present invention belongs to the technical field of nuclear magnetic resonance hyperpolarization, and particularly relates to a SABRE hyperpolarization method for enhancing the signal of active hydrogen by means of dynamic covalent bond exchange, which specifically comprises the following steps: preparing a NMR sample to be measured, collecting a thermal equilibrium 1 1H NMR spectrum, hyperpolarization transfer process, detecting the hyperpolarized active hydrogen signal, and post-processing and analyzing the data. The present invention integrates the dynamic exchange of hemiacetal formed by aldehyde group and hydroxyl group into SABRE, combines it with coordination-based SABRE, realizes the transfer of the spin state of para-hydrogen (para-H2) to the hemiacetal product, and further obtains the hyperpolarization of CD3OH and active hydrogen through the dynamic exchange of hemiacetal.
Owner:XIAMEN UNIV

A fluorescently labeled polysaccharide and a method for fluorescently labeling a polysaccharide

ActiveCN116789866BLuminescent compositionsFluorescein isothiocyanateHistidine
The present invention relates to a method for fluorescent labeling of polysaccharides, and specifically relates to a method for fluorescently labeling polysaccharides and fluorescently labeled polysaccharides. Fluorescein isothiocyanate with a histidine tag is provided; the hemiacetal hydroxyl group of fucoidan and the hydroxyl group of tyramine are subjected to condensation dehydration to form an acetal to obtain fucoidan-tyramine, and the amino group in fucoidan-tyramine and the carboxyl group in the fluorescein isothiocyanate with a histidine tag are subjected to an amidation reaction to obtain a crude product; the crude product is successively subjected to impurity removal by a Sephadex G-100 column, purification by a nickel column, and desalting by a Sephadex G-100 column to obtain the product. The fluorescently labeled polysaccharide prepared by the present invention can specifically react with a nickel column, so that the fluorescently labeled polysaccharide can be further separated and purified by the nickel column, thereby improving the fluorescent labeling rate of fucoidan.
Owner:SHANDONG UNIV

A low-cost method for preparing 2-chloro-5-(β-D-glucopyranoglucose-1-yl)-4'-ethoxydiphenylmethane

PendingCN122301823APtru catalystMeth-
This invention discloses a low-cost method for preparing 2-chloropyranose-1-yl)-4''-ethoxydiphenylmethane, belonging to the field of pharmaceutical synthesis technology. The method uses a hemiacetal compound of formula I as a substrate, and in an organic solvent, under the action of a heterogeneous solid acid catalyst with a water content of less than 2.0% and polymethylhydrosiloxane with specific parameters, a reduction reaction occurs at -20°C to 25°C, highly selectively preparing the compound of configuration II. This invention ingeniously utilizes the spatial confinement effect formed by the matching of the micropores of the dehydrated solid acid and the macromolecular reducing agent, achieving a breakthrough increase in the diastereomeric excess percentage of the target product to an extremely high level. Simultaneously, it completely eliminates the constraints of the traditional -78°C cryogenic conditions, significantly reducing reagent costs. The catalyst can be easily recovered and reused through solid-liquid separation, and no fluorine- or boron-containing waste liquid is generated, making it highly promising for industrial application.
Owner:JIANGSU ALPHA PHARM CO LTD

Preparation method of organic sulfinate compound

The invention discloses a preparation method of an organic sulfinate compound, which comprises the following steps: (1) carrying out hemiacetalation reaction and / or hemiketalization reaction on an aldehyde acid and / or ketonic acid compound with a structure as shown in a formula I and an alcohol compound in the presence of an alkaline substance to obtain an intermediate product; (2) carrying out a sulfonation reaction on the intermediate product and dithionite to obtain an organic sulfinate compound with a structure as shown in a formula II; wherein R1 is H or C1-C6 alkyl, R2 is H or C1-C6 straight-chain alkane, R3 is M or C1-C6 straight-chain alkane, and M is potassium, sodium or lithium. According to the method, an alcohol compound reacts with an aldehyde acid and / or keto acid compound to generate a hemiacetal compound and / or a hemiketal compound, and then the hemiacetal compound and / or the hemiketal compound react with sodium hydrosulfite to generate a sodium sulfinate product, so that side reaction can be inhibited. According to the method, only sulfinate is generated, a small amount of solvent is used in the separation process, the energy consumption is low, and the operation is simple. # imgabs0 #
Owner:CHINA PETROLEUM & CHEMICAL CORP +1

Quinonoid diterpene stilbene ester adducts, methods of making and uses in treating melanoma

The application belongs to the field of organic synthesis and medicinal chemistry, and relates to synthesis and AhR inhibitory activity research of quinoid diterpenyl benzene styrene alcohol ester adducts. The compound of the application has a structure shown in general formula (I), tanshinone is used as a raw material, and quinoid diterpenyl benzene styrene alcohol ester adducts are synthesized through eight steps. The raw material of the application is easy to obtain, and the reaction is easy to control. The application has important reference significance for preparing benzene 1,4-dioxane hemiacetal compounds. The prepared quinoid diterpenyl benzene styrene alcohol ester adducts have significant AhR inhibitory activity, and can be used as tumor immunotherapy drugs for further drug preparation.
Owner:INST OF MATERIA MEDICA CHINESE ACAD OF MEDICAL SCI

Thermosetting resin composition and color filter

Provided is a thermosetting resin composition containing an epoxy compound (A), a polycarboxylic acid hemiacetal ester (B), and a silicone-based surfactant (C), the epoxy compound (A) containing an epoxy group-containing polymer having as structural units (a1), (a2) and (a3) monomers and having an epoxy equivalent weight of 155-240 g / mol, the amount of (C) being 0.01-1.0 parts by mass per 100 parts by mass of the total of (A) and (B), and the amount of the silicone-based surfactant (C) being 0.01-1.0 parts by mass per 100 parts by mass of the total of (A) and (B). The functional group equivalence ratio of the carboxyl group (B) to the total epoxy group (A) is in the range of 0.25-0.95. The thermosetting resin composition can form a cured film with excellent NMP resistance and low metal ion residue, and has good coating property at low viscosity.
Owner:NOF CORP