54 results about "Syringaldehyde" patented technology

The invention relates to a method for preparing and separating p-hydroxybenzaldehyde, vanillin and syringaldehyde from lignin, which comprises the following steps: (1) preparing a Lab[1-x]Cu[x]O[3] perovskite type composite oxide catalyst; and (2) carrying out centrifugal separation on a crude aromatic aldehyde product, acidifying, carrying out vacuum drying, and extracting with trichloromethane to obtain a mixture of p-hydroxybenzaldehyde, vanillin and syringaldehyde; dissolving the mixture of p-hydroxybenzaldehyde, vanillin and mixture in anhydrous alcohol, adding ammonia water to form a precipitate, filtering, and regulating the pH value of an alcohol solution of the filtered solid with a sulphuric acid solution, thereby obtaining a crude syringaldehyde product; and concentrating the filtered liquid while depressurizing to obtain a solid, rectifying in a nitrogen atmosphere, and respectively collecting fractions at different temperatures, thereby obtaining the vanillin and p-hydroxybenzaldehyde. The invention increases the comprehensive utilization ratio of the wood fibers, lowers the cost of the wood fiber fuel alcohol, and has great economic and social meanings.

The invention discloses a chalcone derivative with good anti-free radical oxidative damage activity. The structural formula of the chalcone derivative is shown as the following. The preparation method of the chalcone derivative includes: letting syringaldehyde and para-substituted acetophenone react in piperidine and under a high temperature so as to generate corresponding substituted chalcone; reacting purified chalcone with sodium borohydride under a cerous chloride heptahydrate condition to generate a chalcone derivative crude product, and then conducting purification. , Compared with ascorbic acid, the product provided by the invention has low anti-DPPH free radical and anti-ABTS<+> free radical IC50 value, and strong free radical scavenging ability, thus having broad application prospects in preparing drugs for treating neurodegenerative diseases. (formula I).

The invention relates to a method for preparing syringaldehyde by oxidative degradation of lignin, which comprises the following steps of: 1) dissolving an oxidative degradation product solid of the lignin by using an organic solvent, adding ammonia water to obtain a syringaldehyde and ammonia water complex precipitate, performing centrifugal separation, and acidifying the complex precipitate to obtain syringaldehyde; and 2) evaporating to dryness under reduced pressure and centrifuging to obtain ammonia water mixed solution, performing bromination on the obtained solid substance and elemental bromine or bromine hydride solution, and performing methoxylation reaction on the bromination product and sodium methoxide under the catalysis of cuprous salt to obtain the syringaldehyde. By the steps, the oxidative degradation product of the lignin is all converted into the same product, namely the syringaldehyde, the yield of the syringaldehyde is 50-60 percent, the utilization rate of lignocellulosic materials is improved, the cost of cellulose alcohol and papermaking industry is reduced, and the method has important meaning for realizing high value-added industrial development of the lignin and industrialization of cellulose ethanol and promoting agricultural sustainable development.

In Part A, the present invention relates to novel compositions X comprising (1) at least one bitter blocking agent; (2) at least one carbonyl compound; and (3) at least one lactone, in particular to compositions X comprising (i) naringin; (ii) methoxy salicylaldehyde; (iii) syringaldehyde; (iv) massoia lactone; and (v) whiskey lactone; to the use of the compositions X for modifying, masking, reducing and / or suppressing an unpleasant off- taste, aftertaste or lingering sweetness of at least one sweetener, sweetness enhancer or consumable product; and to a process for the preparation of the compositions X. Further, the invention relates to sweetener compositions comprising at least one sweetener and the novel compositions X; to a method of providing sweetener or sweetness enhancer compositions; to methods of modifying, masking, reducing and / or suppressing an unpleasant off-taste, aftertaste or lingering sweetness of at least one sweetener or sweetness enhancer; and to tabletop sweetener compositions comprising the novel compositions X. The invention also relates to consumable product compositions comprising a consumable product and the novel compositions X; to methods of modifying, masking, reducing and / or suppressing an unpleasant off-taste, aftertaste or lingering sweetness of a consumable product composition; and to methods of imparting rich taste to a consumable product. In Part B, the present invention inter alia relates to sweetener composition comprising (ii) a sweetener; and (ii) at least one flavoring, wherein the at least one flavoring is suitable for modifying, masking, reducing and / or suppressing an unpleasant off-taste of the sweetener in a consumable product composition formed by adding the sweetener composition to a consumable product; and wherein a weight ratio of the at least one flavoring to the sweetener in the consumable product composition is such that the sweetness of the sweetener is detectable by taste in the consumable product composition and the flavor of the at least one flavoring is not detectable by taste in the consumable product composition. The invention further relates to a sweetness enhancer composition comprising (i) a sweetness enhancer; and (ii) at least one flavoring; wherein the at least one flavoring is suitable for modifying, masking, reducing and / or suppressing an unpleasant off-taste of the sweetness enhancer in a consumable product composition formed by adding the sweetness enhancer composition and a sweetener to a consumable product; and wherein a weight ratio of the at least one flavoring to the sweetness enhancer in the consumable product composition is such that the sweetness enhancer is capable of enhancing a sweetness of the sweetener present in the consumable product composition and the flavor of the at least one flavoring is not detectable by taste in the consumable product composition. The invention further relates inter alia to the respective consumable products.

The invention discloses a method for preparing aromatic aldehyde compounds from sodium lignosulfonate, which comprises the following steps: adding sodium hydroxide into deionized water to obtain a sodium hydroxide water solution, adding sodium lignosulfonate, stirring uniformly, adding an oxidizer and a catalyst to react while keeping the temperature at 5-60 DEG C, regulating the pH value of the reaction solution to 1-3, carrying out vacuum filtration to remove the unreacted sodium lignosulfonate, extracting the obtained supernate with an organic solvent ethyl acetate or chloroform, and carrying out rotary evaporation concentration on the obtained organic phase at the controlled temperature of 30-55 DEG C, thereby obtaining an aromatic aldehyde mixture; and carrying out column chromatography separation on the obtained aromatic aldehyde mixture to respectively obtain vanillin, p-hydroxybenzaldehyde and syringaldehyde. The preparation method has the advantages of low preparation cost, simple technical operation, mild reaction conditions and no secondary pollution, reduces the pollution of papermaking wastewater on the environment, effectively utilizes the lignin resources, and obtains the high-added-value aromatic aldehyde compounds.

The invention provides polyester of a biological carbonic-ester-contained structure and a preparing method and application of the polyester. The structural formula of the polyester is shown in the description. The preparing method includes the steps of making one biological monomer in vanillic aldehyde, syringaldehyde and p-hydroxy benzaldehyde serve as the raw material to react with triphosgene under the effect of a catalyst, recrystallizing a reaction product to obtain a dialdehyde monomer of a biological carbonic-ester-contained structure, making the dialdehyde monomer serve as the raw material to react with sodium borohydride, conducting recrystallizing or column-passing separating on a reaction product to obtain a diol polymerizable monomer of a biological carbonic-ester-contained structure, making the diol polymerizable monomer react with acyl chloride under the effect of a catalyst, dropping a reaction product in an anti-solvent for regeneration, and conducting washing and purifying to obtain the polyester of the biological carbonic-ester-contained structure. The polyester is of the biological carbonic-ester-contained structure and is friendly to the environment; the preparing method of the polyester is simple, no harmful substances are generated in production, pollution is low, and cost is low.

The invention provides a novel anti-tumor drug which is represented by the molecular formula (I) and specifically relates to anti-tumor 2-amino nicotinonitrile. The invention further provides a synthetic method of the anti-tumor drug. The method includes dissolving 2mmol of vanillic aldehyde or 2mmol of syringaldehyde, 2mmol of acetophenone and 2mmol of malononitrile in 1, 4-dioxane, then adding 4mmol of ammonium acetate, heating a mixture at the temperature of 120 DEG C for reaction for 20 minutes by using a microwave with the length of 300W as an assistant, adding ice water to the reaction mixture to separate out a product, and finally subjecting the mixture to recrystallization to obtain the 2-amino nicotinonitrile. The synthetic method of the anti-tumor drug is simple, and the anti-tumor drug can be rapidly and efficiently synthesized by means of a one-pot four-component reaction assisted by the microwave. The anti-tumor drug which is represented by the molecular formula (I) is capable of obviously inhibiting activities of proliferation of liver cancer cells, gastric cancer cells, breast cancer cells, pancreatic cancer cells, brain cancer cells, lung cancer cells and ovarian cancer cells.

The invention discloses a method for extracting lignins from lignocellulose materials to prepare syringaldehyde by catalytic conversion. The method mainly includes: 1) using high-boiling solvent for extracting the lignins from the lignocellulose materials of agricultural wastes such as nut shells and straws; 2) preparing perovskite type oxides LaNi1-xCuxO3 and LaFe1-xCuxO3, and loading to carriers such as molecular sieves and MCM-22 type molecular sieves to obtain heterogeneous perovskite type oxide catalysts; 3) applying the prepared catalysts to catalytic oxidation of the lignins for preparation of the syringaldehyde; 4) after reaction is finished, filtering to separate out the heterogeneous catalysts, and recycling after reduction regeneration.

The invention relates to a method for preparing extracting liquid containing vanillic aldehyde and syringaldehyde through catalytic oxygen decomposition of lignin. The method comprises the following steps: (1) preprocessing corn straw lignin in a NaHCO3 water solution; (2) putting the corn straw lignin preprocessed in the step (1) and a perovskite type catalyst into a closed reaction kettle, introducing O2 for reacting by taking an ethanol / water mixed solution as a solvent, after the reaction is finished, cooling the reaction liquid to the normal temperature, and carrying out discharging; and(3) sequentially carrying out filtration, rotary evaporation and ethyl acetate extraction on the discharged product in the step (2), so as to obtain the extracting liquid containing vanillic aldehydeand syringaldehyde. The method is mild in reaction condition and environment-friendly, the high-valued utilization of biomass can be realized, and the method has important significance to the protection of the ecological environment.

The invention relates to a preparation method of complex maple extract Maillard reactive flavor, including the steps: 1) according to the component analysis result of traditional maple extract, removing components such as pectin, cellulose, protein, tartaric acid, shikimic acid, 2-Ethyl Hexanoic Acid, Hexanoic Acid, Furfural, Furfuryl Alcohol, 2, 3-Dimethylpyrazine, 2, 5-Dimethylpyrazine, 2, 6-Dimethylpyrazine, Syringaldehyde and 2, 6-Dimethoxyphenol, as a simulation formula; 2) preparing each raw material component according to a simulation formula to obtain compound maple extract; 3) diluting that compound maple extract with water, uniformly mix with amino acids, adjusting pH to 8-10, and reacting at high temperature and high pressure in an inert gas atmosphere to obtain maple extract solution with Maple reaction; and adjusting pH to 5 to 7, and then obtaining the product through vacuum freeze-dry. The flavor product has stable quality and is added into the reconstituted tobacco of the paper-making process, which solves the problems of less aroma, light aroma, heavy wood gas and heavier hot feeling of the smoke existing in the reconstituted tobacco in the paper-making process.

The invention provides application of syringaldehyde to preparation of medicine for preventing intestinal injuries caused by ionizing radiation, a pharmaceutical form and an administration mode.The medicine for preventing intestinal injuries caused by ionizing radiation with syringaldehyde as the active component has the advantages of being small in toxic and side effect, remarkable in treatment effect, convenient and safe to use and the like, is suitable for different people such as acute radiation syndrome patients, nuclear personnel, soldiers and officials, astronauts and radiotherapy patients, and can be used before treatment or task execution and during work.Syringaldehyde shows unique performance in prevention of intestinal injuries caused by ionizing radiation, and has wide application prospects in the medical field of China.

The invention discloses a preparation method for total synthesis of 4'-demethylepipodophyllotoxin (also named as epipodophyllotoxin). The preparation method comprises the following steps: (1) syringaldehyde (compound 1) used as an initial material and benzyl methoxyacyl used as a protective group are in favor of a chemical reaction of finally removing the protective group to obtain a target compound; (2) a chiral target object is produced by adopting an asymmetric hydrogenation reduction reaction in which a chiral ligand (s-BINAN Ru (II)) participates; and (3) a reaction of hydrogenating and deprotecting groups is also carried out in parallel while chiral catalytic hydrogenation is carried out. The reaction steps and treatment are saved, the route selection is targeted to the target compound, the production cost is low, and the environment is friendly.

The invention discloses bridge chain structure biological base polyester, a preparation method and an application thereof. The method comprises the following steps: firstly enabling one of vanillic aldehyde, syringaldehyde and 5-hydroxymethylfurfural to be coupled with 1,2-dibromoethane or dichlorodimethylsilane, and performing catalytic oxidation, to obtain a new-type diacid monomer containing abridge chain structure; and then, performing an esterification reaction on the diacid monomer, aliphatic diol and a catalyst in 160-180 DEG C and nitrogen protection, to obtain a prepolymer; stoppingfeeding a nitrogen gas, rising a temperature to 220-240 DEG C, opening a vacuum pump and reducing a system pressure below 20 Pa, and performing a polycondensation reaction, to obtain a polymer crude product; adding an enough amount of chloroform to the polymer until the polymer is completely dissolved, to obtain clear liquid, dropwise adding the clear liquid to an alcohols solvent, generating a white precipitate, centrifugally separating, to obtain a white solid, alcohol-washing the white solid, filtering, and drying a filter residue, to obtain the biological base polyester containing the bridge chain structure. The bridge chain structure biological base polyester has the characteristics of green and environmental reaction process, high polyester yield, good heat stability and degradationproperty of a polyester material and the like.

The invention relates to an external preparation composition, and particularly relates to a composition for skin damage repair. The composition for skin damage repair is prepared by mixing hydroxypropyl-beta-cyclodextrin (Hp-beta-CD) included syringaldehyde, N-acetyl-L-cysteine (LNAC), SOD, potassium sorbate for preventing the microbial growth and a water-soluble film forming agent consisting of high-modular compounds. The invention also relates to a preparation method of the composition for skin damage repair and an application of the composition for skin damage repair to the skin damage repair. The composition makes up the shortages of the current clinical burn medicines and is capable of accelerating the healing of the wound surfaces.

The invention discloses a novel application of syringaldehyde to preparation of drugs. The novel application of the syringaldehyde to preparation of drugs is application of syringaldehyde to preparation of a radiocancerogenesis protection drug. The radiological protection drug with syringaldehyde which serves as an active component has the following advantages that the drug is low in toxicity and free of obvious adverse reactions, the treatment effect is obvious, the drug is administrated by a dosage of 10mg per mouse in 30 minutes before radiation, the low-dosage radiation accommodation adsorption is 7Gy, the occurrence rate of spleen neoplasms of the mouse is reduced by 20%, the occurrence rate of tumors of liver is reduced by 15% and the occurrence rate of thymic tumor is reduced by 24% after radiating for 15 months, the injury to the animal hemopoietic system caused by radiating can be effectively protected under the concentration of 100mg / Kg, the myeloid erythroid ratio and the original cell ratio of the radiated mouse bone marrow are reduced, and the spleen, the liver and the thymus of the radiated animal are protected. The properties show that the syringaldehyde takes a unique role in the radiating and reducing the occurrence of the cancer; the syringaldehyde has a wide application prospect in the national defense medical field.

The invention provides a bio-based carbonate structure-containing polyurethane, and a preparation method and an application thereof. The structural formula of the polyurethane is shown in the description. The preparation method comprises the following steps: reacting a bio-based monomer in vanillin, syringaldehyde or p-hydroxybenzaldehyde, used as a raw material, with triphosgene under the actionof a catalyst, and recrystallizing the obtained reaction product to obtain a bio-based carbonate structure-containing dialdehyde monomer; reacting the dialdehyde monomer, used as a raw material, withsodium borohydride, and performing recrystallization or column separation on the obtained reaction product to obtain a bio-based carbonate structure-containing diol polymeric monomer; and reacting thebio-based carbonate structure-containing diol polymeric monomer with diisocyanate under the action of a catalyst, dropwise adding the obtained reaction product into an anti-solvent, regenerating thereaction product, and washing and purifying the regenerated reaction product to obtain the bio-based carbonate structure-containing polyurethane. The polyurethane has the characteristics of good waterresistance, good heat resistance, good chemical resistance, good solvent resistance and good mechanical properties, and the preparation method has the advantages of simplicity, no harmful substancesgenerated during production, small pollution and low cost.

The invention belongs to the technical field of production of slim cigarette filter sticks, and in particular relates to clove essence for a fragrance line in a slim filter stick and an application ofthe clove essence. The clove essence consists of the following components in percentage by mass: 10.0-15.0% of clove oil, 2.0-5.0% of syringaldehyde, 0.05-0.1% of octanal, 0.05-0.1% of nonanal, 0.05-0.1% of decanal, 0.2-0.5% of linalool, 0.1-0.2% of terpilenol and 79.0-87.55% of caprylic / capric triglyceride. According to the invention, the clove essence for the fragrance line in a slim cigarettehaving special fragrance is provided, and through coordination with the improvement of the structure of the slim cigarette filter stick, the smoking effect of the slim cigarette can be improved obviously; therefore, a relatively good practical value is guaranteed; the variety of cigarette products is enriched; and meanwhile, the clove essence has relatively good exemplary promotion and applicationsignificance for the design, development as well as production and sale of novel slim cigarettes.

The invention provides pseudomonas aeruginosa, a method for screening the same and application of the pseudomonas aeruginosa to lactic acid fermentation on straw. A preservation number of the pseudomonas aeruginosa is CCTCC NO:M2018169. The pseudomonas aeruginosa, the method and the application have the advantages that the pseudomonas aeruginosa is acquired from activated sludge in aerobic ponds of municipal sewage treatment plants by means of screening, diversified typical products generated in lignin pretreatment procedures can be efficiently degraded by the pseudomonas aeruginosa, and the degradation rates of the pseudomonas aeruginosa for various substrates including cumaric acid, parahydroxybenzaldehyde, vanillin, ferulic acid and syringaldehyde can reach 100% after culture is carriedout under the condition of the temperatures of 37 DEG C for 36 hours; the typical products can be prevented from inhibiting microbial metabolism during the lactic acid fermentation on the straw whenthe pseudomonas aeruginosa is used for carrying out the lactic acid fermentation on the straw, accordingly, the straw conversion rate of lactic acid can be increased, the pseudomonas aeruginosa is short in fermentation period, and the fermentation is accomplished after culture is carried out for 48-72 h; the plant straw is used as a fermentation raw material, accordingly, waste can be turned intowealth, environmental pollution can be reduced, and the pseudomonas aeruginosa, the method and the application have positive significance in guaranteeing the food safety.

The invention discloses acinetobacter baumannii and a method for producing laccase and an application thereof. The acinetobacter baumannii is submitted for preservation on May 7 in 2014 and has a preservation number of CCTCC NO:M201489. The invention also discloses a method for producing laccase by using acinetobacter baumannii and an application of laccase in dye decolorization. The acinetobacter baumannii disclosed by the invention is relatively high in activity, high in growth rate, good in stability and difficult in variation, and can be subjected to fermentation culture to obtain laccase; the method for producing laccase by using the acinetobacter baumannii is simple to operate and low in cost; the obtained laccase is high in activity; and when laccase produced by the method disclosed by the invention is combined with syringaldazine to serve as a decoloring solution, the decoloring solution is high in activity and relatively high in stability, and then the decoloring effect of laccase can be effectively improved.

The invention discloses a method for efficiently degrading tetracyclic and sulfonamide antibiotics by laccase. The method comprises the following steps: S1, fermenting by adopting Pycnoporus sp. SYBC-L10 to produce laccase; and S2, firstly adjusting the pH value of a waste liquid containing tetracyclic antibiotics or sulfonamide antibiotics to 3.0-6.0, then adding the laccase obtained in the stepS1, simultaneously adding a small molecular mediator ABTS or syringaldehyde, standing and carrying out incubation for a period of time. The invention provides laccase capable of efficiently degradingtetracyclic and sulfanilamide antibiotics in the environment and a method. Compared with reported similar laccase, the laccase of the invention has the advantages that the effect is obviously quicker(generally, 50 mg L<-1> of antibiotics are degraded only within 5-10 min). Compared with a traditional physical-chemical method, the method of the invention is green, safe and environmentally friendly, meets the sustainable development requirement and has wide application prospects in the application of antibiotics to the future environment treatment.

The invention discloses bacillus coagulans YSF17 and application thereof, and belongs to the technical field of microorganisms. The strain is preserved in China Center for Type Culture Collection, the preservation number is CCTCC M 2021965, the preservation place is Wuhan University, Wuhan, China, and the preservation time is August 2, 2021. The bacillus coagulans YSF17 disclosed by the invention has the capacity of secreting amylase and cellulase, can produce acid by utilizing 11 monosaccharides or oligosaccharides, and can resist the high temperature, bacteria can grow at 60 DEG C, and the survival rate of spores can reach 80% after the spores are treated at the high temperature of 90 DEG C for 30 minutes; the strain can resist various phenolic substances such as vanillin, syringaldehyde, benzaldehyde, gossypol and the like, is used for fermentation of cottonseed meal and soybean meal, can effectively reduce the content of anti-nutritional factors such as gossypol, stachyose, raffinose and the like, shortens the fermentation period, implements cost reduction and synergism, and has very good application prospects in development and application of protein feeds.

The invention relates to a method for preparing aromatic aldehyde through visible light catalytic oxidation of lignin. According to the method, a transition metal vanadium salt is used as a visible light catalyst, various lignin extracts and industrial lignin are used as reaction raw materials, and under the excitation of visible light irradiation, the lignin is directly catalyzed to be oxidized and cracked to prepare an aromatic aldehyde compound. The method comprises the following reaction processes of adding a certain amount of the lignin raw material and the catalyst into a quartz photoreaction tube, adding a certain amount of a solvent and magneton, introducing oxygen, turning on a visible light source, carrying out a photoreaction under stirring, and obtaining aromatic aldehyde products such as vanillin and syringaldehyde after the reaction is carried out for a period of time. According to the method, visible light is used for promoting a biomass catalytic conversion reaction, and the reaction is carried out in an oxygen atmosphere; and the raw material lignin is low in price and wide in source, the reaction process is simple, the aromatic aldehyde compound has wide application value, and the method is a green novel method for preparing the aromatic compound by photocatalysis of the lignin.

The invention provides a synthetic method of Tenuifoliside B. Sucrose, syringaldehyde and p-hydroxybenzoic acid are used as the starting materials, and subjected to 6 steps of chemical conversion reactions to realize total synthesis of Tenuifoliside B for the first time. The raw materials of sucrose, syringaldehyde and p-hydroxybenzoic acid employed by the invention are convenient, easily available and at controllable low cost; each step of chemical reaction has mild reaction conditions and is easy to implement and operate in the practical application; each step of chemical reaction has high reaction conversion rate, especially the first three reaction steps have mild reaction conditions, simple operations, high yield, small amount of by-products and total yield at about 22.3%; and the Tenuifoliside B can be directly used for subsequent steps of the synthesis reaction without fine column chromatography purification.

The invention discloses a method for degrading antibiotics in aquaculture sewage by combining industrialized laccase and a syringaldehyde mediator, wherein sulfanilamide-based antibiotics in aquaculture wastewater are degraded by combining industrialized Novozym 51003 laccase and a syringaldehyde mediator. The method comprises: adding a certain amount of a sulfanilamide-based antibiotic mother liquor to aquaculture pond sewage, adding a syringin mediator mother liquor, finally adding Novozym 51003 laccase, adjusting to a suitable pH value, carrying out an oscillation reaction for 0.5-6 h at a certain temperature, and carrying out a catalytic oxidation degradation reaction so as to effectively degrade the sulfanilamide-based antibiotics in the sewage. According to the present invention, the industrialized laccase is used as the laccase source, and the ecological effect and the degradation effect of the mediator are comprehensively considered by determining the concentration of the syringaldehyde mediator, such that the treatment process is simple, the cost is low, and the pollutant removal rate is high.

The invention relates to the technical field of organic synthesis, in particular to a method for continuously preparing vanillin and syringaldehyde. According to the method for continuously preparingthe vanillin and the syringaldehyde, the vanillin and the syringaldehyde are continuously synthesized and produced by taking the p-hydroxy benzaldehyde as the raw material, and the vanillin and the syringaldehyde are obtained by directly etherifying brominated products without refining in the process, so that the aims of shortening the process, improving the yield, reducing the cost, being safe and environment-friendly and easily realizing industrial production are achieved.

The invention discloses a method for preparing aromatic aldehyde compounds from sodium lignosulfonate, which comprises the following steps: adding sodium hydroxide into deionized water to obtain a sodium hydroxide water solution, adding sodium lignosulfonate, stirring uniformly, adding an oxidizer and a catalyst to react while keeping the temperature at 5-60 DEG C, regulating the pH value of the reaction solution to 1-3, carrying out vacuum filtration to remove the unreacted sodium lignosulfonate, extracting the obtained supernate with an organic solvent ethyl acetate or chloroform, and carrying out rotary evaporation concentration on the obtained organic phase at the controlled temperature of 30-55 DEG C, thereby obtaining an aromatic aldehyde mixture; and carrying out column chromatography separation on the obtained aromatic aldehyde mixture to respectively obtain vanillin, p-hydroxybenzaldehyde and syringaldehyde. The preparation method has the advantages of low preparation cost, simple technical operation, mild reaction conditions and no secondary pollution, reduces the pollution of papermaking wastewater on the environment, effectively utilizes the lignin resources, and obtains the high-added-value aromatic aldehyde compounds.

Methods of depolymerizing lignin and products obtained therefrom. The methods include reacting lignin in a liquid solvent comprising an oxidation catalyst with the solvent being in contact with 02 gas. The solvent can include aprotic polar solvents. The oxidation catalyst can include heterogeneous catalysts. The methods can be used in the oxidative catalytic fractionation of raw biomass to generate soluble aromatic monomers and a solid carbohydrate residue. Depolymerized lignin products include phenolic and benzoquinone monomers, such as p-hydroxybenzoic acid, vanillin, syringaldehyde, vanillic acid, and / or syringic acid.

The invention discloses a synthesis method of Robtein. The method comprises the steps that syringaldehyde and paeonol serve as raw materials, under the action of a basic catalyst, by means of a Claisen-Schmidt condensation reaction, 2',4-dihydroxy-3,4',5-trimethoxy chalcone is directly synthesized, and under the action of hydrobromic acid, ether linkages in molecules are broken and transformed into 2',3,4,4',5-pentahydroxy chalcone which is Robtein, recrystallization is conducted, and then Robtein high in purity can be obtained. The feeding ratio of syringaldehyde to paeonol is syringaldehyde(mol):paeonol(mol)=1:1. Accordingly, synthesis of Robtein is carried out at room temperature and atmospheric pressure, fewer steps are adopted, the reaction time is short, and continuous synthesis canbe conducted without complex separation, and the method is suitable for industrialized production; the total yield exceeds 78%, and the purity of the product is 95% or above. The synthetic process isenvironmental friendly.

The invention discloses a synthesis method of high-purity high-yield syringic acid. The method is characterized by comprising the following steps: esterification, oxidation and hydrolysis, wherein in the esterification step, the molar ratio of syringaldehyde, acid anhydride and solvent is 1:1.5-4:0-10; heating and reflowing are performed for 2-3 hours and cooling is performed for 30-70 DEG C in the esterification step; in the oxidation step, the molar ratio of the syringaldehyde and hydrogen peroxide is 1:1.5-3.5; in the oxidation step, the hydrogen peroxide is continuously added into esterification reaction solution in 0.5-2 hours. The yield of a product prepared by the method is greater than 86.5 percent, and the purity of the product is greater than 98.6 percent.