78results about How to "Difficult to purify" patented technology

The invention provides a preparation method of a 7-keto-6[alpha]-alkyl cholanic acid derivative. According to the preparation method provided by the invention, a 7-keto-6[beta]-alkyl cholanic acid derivative, as shown by a formula II, is used as a raw material, and the 7-keto-6[alpha]-alkyl cholanic acid derivative is prepared by converting a 6[beta] configuration into a 6[alpha] configuration under an acid or alkali condition. The invention also provides a 7-keto-6[beta]-alkyl cholanic acid derivative and an application thereof in preparation of 3[alpha],7[alpha]-dihydroxy-6[alpha]-alkyl-5[beta]-cholanic acid. The preparation method provided by the invention is simple and convenient, and is high in configuration conversion rate, and the product, the 7-keto-6[alpha]-alkyl cholanic acid derivative, is easy to purify, so that the purification difficulty for preparing the 3[alpha],7[alpha]-dihydroxy-6[alpha]-alkyl-5[beta]-cholanic acid is reduced.

The invention relates to a method for preparing health-care drink containing the dendrobium. Due to the adoption of the advanced technology for extracting the effective component of the dendrobium by ultrasonic waves, the time for extracting the effective component of the dendrobium is 2/3 of the time for extracting the effective component of the dendrobium with the conventional method, the temperature for extracting the effective component of the dendrobium is low, the effective component of the dendrobium is easy to separate and purify, and the nutrients are not easy to destroy. The health-care drink containing the dendrobium is prepared by diluting the extract in purified mineral water and mixing the diluted extract with honey, oligoisomaltose and potassium sorbate, etc. The health-care drink containing the dendrobium has the outstanding efficacy of tonifying the stomach, promoting the fluid, nourishing the yin and reducing the internal heat.

The invention discloses a synthetic and purifying method of a near-infrared indole hepatmethine cyanine dye. The method does not need any catalyst, only adopts ethanol as a solvent, allows a 1-type intermediate of N-methyl (or ethyl, benzyl)-2,3,3-trimethyl-3H indole-5 potassium sulfonate quaternary ammonium salt to react with a condensing agent of 2-chloro-1-formoxyl-3-hydroxyl methylene cyclohexene through a one-step method to obtain the 2-type serial near-infrared indole hepatmethine cyanine dye; no traditional column chromatography separation and purification is adopted, and a solvent recrystallization method is adopted which can obtain the serial near-infrared indole hepatmethine cyanine dye with high efficiency. The invention not only has mild reaction conditions, is simple in separation and purification, is green and environment-friendly, but also has great industrial production value.

The invention belongs to the technical field of organic photoelectric materials, and in particular relates to polyhedral oligomeric silsesquioxane (POSS)-based solid ionic liquid, and a preparation method and application thereof. The solid ionic liquid provided by the invention contains the POSS and ester group substituted imidazole iodate and is an organic/inorganic hybrid material taking the POSS as a core, and the conductivity of the solid ionic liquid can be adjusted through different groups grafted on the POSS. The ionic liquid can serve as solid electrolyte to be applied to a full-solid-state dye-sensitized solar battery, and energy conversion efficiency of 7.1% and high long-term stability can be achieved. Compared with the solid ionic liquid not containing the POSS, the POSS-based solid ionic liquid has the advantages that the solid electrolyte provided by the invention is not crystallized, has high wettability on the surface of titanium dioxide due to a large amount of Si-O bonds, and is favorable for filling of the solid electrolyte in titanium dioxide nanopores and regeneration of dye.

The invention provides a preparation method of an intermediate compound 7 of an SGLT-2 diabetes inhibitor dapagliflozin and an intermediate compound 8 of a SGLT-2 diabetes inhibitor empagliflozin, and new synthesis method of two final products. The preparation method comprises the following steps: carrying out carbonyl group reduction and hydroxyl group protection on a (5-halo-2-chlorophenyl)(4-ethoxyphenyl)ketone compound 1 used as an initial raw material to obtain a Grignard addition reaction key compound 4, and carrying out Grignard addition and acetylation to obtain the compound 7 and the compound 8. The dapagliflozin and the empagliflozin are respectively prepared from the compound 8. The methods have the advantages of simplicity in operation, high yield, high purity of the obtained products, and suitableness for amplified production.

The invention discloses a bisexual flower breeding method of manihot esculenta grant, and belongs to the technical field of agricultural cultivation. The breeding method comprises steps as follows: planting, top application, secondary top application, hormone spraying, nutritional regulation before flowering, pinching, pollen viability determination, crossbreeding, pollination, selfing isogeneity and final-period management. With the adoption of the breeding method, on the one hand, the problem of the small quantity of pollinating female flowers during crossbreeding of manihot esculenta grant is solved, more female flowers with different genotypes are provided, and the crossbreeding efficiency is improved; on the other hand, the bisexual flower of manihot esculenta grant is discovered for the first time, and an effective isogenic method adopting a manihot esculenta grant inbred line is provided; and further, the bisexual flower is formed through induction for the first time in the manihot esculenta grant breeding technology, the bisexual flower is used for crossbreeding, a novel crossbreeding method is created, and a new field is created for manihot esculenta grant hybrids.

The present invention relates to an Exendin 4 polypeptide fragment, which has hypoglycemic activity, and can be used for the treatment of type II diabetes mellitus. The polypeptide sequence described herein is HGEGTX1TSDLSKQX2EEEAVX3LFIEWLKNGX₄PX₅, where X₁ represents Phe or Tyr, X₂ represents Met, Ile or Leu, X₃ represents Lys, X₄ represents Gly or deletion, X₅ represents Arg or deletion. Additionally, the present invention relates to a method for the Exendin 4 polypeptide fragment preparation.

The present invention is four analogs of endomorphin-1, [GMLPC]-FM-1, [GMLDC]-EM-1, [GMDPC]-EM-1 and [GMDDC]-EM-1, prepared through liquid phase synthesis and their preparation process. Serial pharmacological activity identifying measurements shows that these four analogs have enzymolysis stability in brain plasmalemma and blood serum of mouse obviously higher than their precursor, longer pain relieving time, and higher integral liposolubility. The present invention is significant for developing endomorphin-1 into clinical polypeptide analgesic.

Belonging to the field of biomedicine, the invention provides an endomorphin analogue with the first position, the second position and fourth position respectively modified by tyrosine or 2, 6-dimethyltyrosine, N-methyl-D alanine and alpha-alkenyl-beta-amino acid and a synthesis method thereof. The endomorphin analogue is obtained by substituting the first position amino acid of endomorphin (EM1 and EM2) with tyrosine or 2, 6-dimethyltyrosine, substituting the second position amino acid with N-methyl-D alanine, and substituting the fourth position amino acid respectively with phenyl or 2-furyl replaced alpha-alkenyl-beta-amino acid, and is named as MEL-N16 series. Radioligand receptor binding experiment, isolated organ bioassay, in-vitro enzymolysis stability and warm bath tail flick analgesic experiment results show that the endomorphin analogue synthesized by the method provided by the invention has higher affinity than an endomorphine matrix, high enzymolysis stability and high analgesic activity, and has very good clinical application value in preparation of analgesic drugs.

The present invention describes a method for separating sterols from neutral substances comprising the sterols. The method generally starts with extracting a hydrocarbon fraction from neutral substances. The hydrocarbon fraction may be optionally washed with water. The neutral substances are separated from the hydrocarbon. The hydrocarbon fraction or the neutral substances are subjected to evaporation fractionating to obtain a sterol-rich fraction. The sterol-rich fraction is dissolved in a solvent, and the sterols are crystallized from the solvent. The obtained sterol crystals are separated from the solvent.

The invention relates to the technical field of gene engineering, in particular to a recombinant vector containing polyhedrosis genes and a method for expressing and purifying proteins. The invention provides a recombinant plasmid pBacPAKph, a recombinant plasmid pBacPAKph-M and a linear virus recon with a connection number of CGMCC No.2768. Linear virus recon BmBacPAKph-M is adopted to infect a host body and express fusion protein of polyhedrosis protein and target protein, the expressed fusion protein is separated and purified, enzyme digestion is carried out on prolease to obtain the target protein. The purified target protein can be prepared into intravenous medicines or used as an object for study on protein functions. A plurality of proteins which are provided by the invention and hard to be expressed and purified but can be easily expressed and purified by protein expression and purification systems, especially membrane proteins have a broad prospect of application.

The invention provides endomorphin-1 modified by unnatural alpha-alkenyl-beta-amino acid, which is characterized in that fourth amino acid of the endomorphin-1 is respectively formed by replacing the alpha-alkenyl-beta-amino acid replaced by phenyl, 2-furan, 3-chlorphenyl, 1, 3-dioxophenyl. Pharmacological activity identity is conducted on the endomorphin-1 modified by the unnatural alpha-alkenyl-beta-amino acid by radiation ligand receptor combination experiments, isolated organ biological assays, cAMP accumulation experiments, separation enzymolysis stability and analgesic tests with water baths. As the results show, the novel analogue has the advantages of high affinity, high enzymolysis stability and high analgesic activity compared with endomorphin-1, thereby having high application value in preparation of polypeptide analgesic medicine.

The present invention relates to the dimethyl sulfoxide solvate of 3-[5-(2-fluorophenyl)-[1,2,4]oxdiazole-3-yl]benzoic acid, wherein the dimethyl sulfoxide solvate has characteristics of good stability, high purity, excellent particle and excellent shape, and is suitable for pharmaceutical preparation applications. The present invention further relates to a preparation method of the dimethyl sulfoxide solvate, a pharmaceutical composition of the dimethyl sulfoxide solvate, and uses of the dimethyl sulfoxide solvate in preparation of drugs for treatment of genetic diseases.

The invention belongs to the field of microbial fermentation engineering, and relates to a preparation method of a recombinant multi-function cellulase. The method is characterized in that multi-function cellulase genes are used to carry out genetic transformation on Coprinus cinereus to obtain a transgenic Coprinus cinereus strain which is used as a producing strain, a mixture of bagasse powder and bean pulp powder is the optimal culture medium, and the recombinant multi-function cellulase is prepared by shake fermentation under the optimal culture conditions. The formula of the bagasse powder and bean pulp powder mixed culture medium comprises 27.9-30.0g/L bagasse powder, 4.3-6g/L bean pulp powder, 0.5-1g/L dipotassium hydrogen phosphate, 0.23-0.69g/L potassium dihydrogen phosphate and 0.5-1g/L magnesium sulfate, and the pH value is 6.25-7.82. The optimal culture conditions are as follows: the culture temperature is 36-37 DEG C, the culture time is 7 days, and the rotation speed of a shaking table is 210r/min. The optimal enzyme yields are as follows: the enzyme activity of Xylanase is 1.66*10<5>U/L, and the enzyme activity of CMCase is 1.7*10<4>U/L. The method provided by the invention can effectively enable the transgenic Coprinus cinereus strain to produce the recombinant multi-function cellulase from low-cost agricultural waste bagasse and bean pulp powder.

The present disclosure provides a method for preparing an alkali and co-producing gypsum, and belongs to the technical field of chemical production. The method comprises the steps of placing a cation exchange membrane into an electrolytic cell, adding a solution of sodium salt of a weak acid and a compound MH to an anode region as an anode electrocatalyst, adding sodium carbonate or sodium hydroxide to a cathode region, adding a compound M as a cathode electrocatalyst, and applying a DC power supply between a cathode electrode and an anode electrode. The electrolysis oxidizes the MH into the M and releases H⁺, Na⁺ in the anolyte penetrates through the cation exchange membrane to reach a cathode region to be combined with OH⁻ in the catholyte to generate NaOH, or further absorbs CO₂ and converts into Na₂CO₃; the anolyte containing a large amount of H⁺ is generated by the electrolysis for dissolution reaction with limestone, and the H⁺ is consumed to generate Ca²⁺, and SO₄²⁻ and Ca²⁺ are combined to generate high-purity CaSO₄ precipitate. According to the present disclosure, a compound capable of generating PCET reaction is used as an electrocatalyst, while M is its oxidation state and MH is its reduction state, and mirabilite and limestone are used as raw materials to realize the preparation of soda ash, caustic soda and gypsum.

The invention discloses an automobile exhaust purifier. The automobile exhaust purifier comprises a shell; an exhaust pipe and an air charging pipe are separately installed at the two sides of the shell; cooling fins are arranged outside the exhaust pipe; the top of the air charging pipe is provided with an oxygen sensor connecting port; a heat insulating layer is arranged at the inner side of theshell; a second exhaust catalyzing plate, a first exhaust catalyzing plate and a cyclone dust collector are sequentially installed inside the shell; the second exhaust catalyzing plate, the first exhaust catalyzing plate and the cyclone dust collector are positioned at the same straight line; and the first exhaust catalyzing plate is positioned between the second exhaust catalyzing plate and thecyclone dust collector. The automobile exhaust purifier disclosed by the invention is provided with the cyclone dust collector and a dust collecting box so that carbon particles cannot be adhered to the purifier; a heat absorbing plate is arranged for making the heat inside the catalyzing plates rise quickly so that the catalyzing plates do not absorb heat too slowly, and thus the exhaust can be easily purified after an automobile is just started; and the cooling fins are arranged for preventing a passenger which walks behind the automobile from being scalded by the exhaust when the automobilestops on a road.

The invention provides a method for synthesizing cholesterol and 25-hydroxycholesterol, which comprises the following steps of: 1) reacting 22-hydroxy-20-methylpregna-4-ene-3-ketone with pyrrolidine or ethylene glycol to protect 3-position carbonyl, then sulfonylating 22-position hydroxyl, and carrying out reduced pressure distillation to obtain 2-hydroxy-20-methylpregna-4-ene-3-ketone and 2-hydroxy-20-methylpregna-4-ene-3-ketone; cholesterol or 25-hydroxycholesterol is obtained through copper-catalyzed Grignard reagent substitution reaction and sodium borohydride reduction reaction. The synthesis method is simple in process, high in yield, low in cost, environment-friendly in process and suitable for industrial production.

The invention provides a method for synthesizing cholesterol from 21-hydroxy-20-methylpregna-4-ene-3-ketone (4-BA) as a raw material. The method comprises the step of: (1) carrying out etherification reaction, oxidation reaction, Grignard reagent addition reaction, sulfonylation reaction, reduction reaction, acetylation reaction and reduction reaction on 4-BA and triethyl orthoformate to obtain cholesterol. The synthesis method is simple in process, high in yield, low in cost, environment-friendly in process and suitable for industrial production.

The invention belongs to the field of synthesis of drugs, and relates to a preparation method of perindopril arginine. The preparation method of perindopril arginine is characterized in that an organic amine salt of perindopril reacts with L-arginine to obtain the perindopril arginine. The prepared perindopril arginine is a white powder, has a purity reaching 99.9% or above, and has a yield of 80% or above, and the method has the advantages of easiness in suction filtration in the technologic process, and no agglomeration phenomenon.

The invention provides a preparation method of recombinant pBpp protein based on an escherichia coli expression system. Through the technical scheme, DNAs in zebra fish faecal bacterium populations are used as templates, pBpp expressed genes are obtained through amplification, then pET28c plasmids are used as carriers, the plasmids are amplified in Escherichia coli TOP10, and then the plasmids are converted into escherichia coli BL21 for protein expression. On this basis, appropriate protein expression and induction conductions are designed for the characteristics of recombination strains, for the intracellular expression pBpp protein, after ultrasonication is carried out on the thallus, nickel beads are firstly used for combining dissociative protein, then protein elution is carried out, and finally dialysis is carried out by using PBS and glycerinum respectively, so that effective purification of the pBpp protein is realized. Experiments find that the pBpp protein prepared in the invention can definitely induce multiplication of beta cells in pancreas, so that the pBpp protein plays a therapeutic effect on diabetes caused by damage of pancreatic Beta cells.

The present invention relates to a plant and a method for producing and treating wood fibres in a plant comprising a fibre-producing part having a chip preheater (1) and a beater (2) for freeing fibre from wood chips. Such a plant and such a method are included as parts in a continuous production process of board and the object is to reduce the emission discharges of foremost VOC and formaldehyde, during different parts of the process as well as from the finished product. The method comprises feeding of wood chips (A) into an upper part of the chip preheater (1), discharge of wood chips in the bottom of the chip preheater to a screw conveyor (12) for further transportation into the beater (2), compression of the wood chips in a compression zone (15) in the screw conveyor, supply of steam (B) into the lower part of the chip preheater for washing fed chips in the counterflow direction, disposal (8) of flue gases in the form of released organic emissions, steam and air in the upper part of the chip preheater, as well as disposal of flue gases generated during the compression through an outlet (13) arranged in the compression zone. The plant has the corresponding parts.