155 results about "Oxazolidine derivatives" patented technology

The present invention is directed to a new process of preparing highly pure Florfenicol. The invention is further directed to new oxazolidine derivatives useful in making Florfenicol and processes of making these derivatives. Examples of such intermediates include (4R,5R)-3-acetyl-2,2-dimethyl-4-hydroxymethyl-5-[4-(methylsulfonyl)phenyl]-1,3-oxazolidine; and (4S,5R)-3-acetyl-2,2-dimethyl-4-fluoromethyl-5-[4-(methylsulfonyl)phenyl]-1,3-oxazolidine.

The present invention relates to formulations of asphaltenes' inhibitor-dispersant additives based on oxazolidine derived from polyalkyl or polyalkenyl N-hydroxyalkyl succinimides. Said formulations can contain inert organic solvents, preferably including: toluene, mixtures of xylene, o-xylene, p-xylene, kerosene, turbo-fuel; or inert hydrocarbon solvents having boiling points within the range of gasoline and diesel; or inert hydrocarbon or organic solvents having a boiling point within a range from 75 to 300° C. The ratio in weight of inert organic solvents to additive that prevents and controls the precipitation and deposition of asphaltenes ranges from 1:9 to 9:1, preferably from 1:3 to 3:1.

The invention provides a preparation method of diethyl N,N-bis(2- hydroxyethyl) aminomethylphosphonate, comprising the following steps: (1) carrying out depolymerization on paraformaldehyde; (2) carrying out ring formation on formaldehyde and diethanol amine to prepare 3-(2- hydroxyethyl)-1,3-oxazolidine; (3) reacting 3-(2- hydroxyethyl)-1,3-oxazolidine with diethyl phosphite in the presence of anhydrous Lewis acid catalysts; and (4) filtering and recovering the catalysts to obtain a yellow transparent liquid product. The overall yield of the whole process reaches more than 99 %, and the content of diethyl N,N-bis(2- hydroxyethyl) aminomethylphosphonate in the product is 94 %-96 %. The preparation method disclosed in the invention is simple and efficient, has the advantages of high product yield, high content of effective components in the product, reduction of temperature in dehydration process, shortening of time, and low energy consumption, reduces the water content of the final product to 0.1-0.2 %, and reduces the dosage of the catalysts by 20-50%. The preparation method is suitable for large-scale industrial production.

The leather tanning agent having no chrome or having little chrome is made up by using amine material containing carboxymethyl group and aliphatic aldehyde compound through the processes of N-carboxymethylation reaction and ring-closing reaction. In addition to oxazolidine naphthenicbase its molecular structure also contains several functional groups of aldehyde group, carboxyl group, hydroxyl group and quaternary amino-group. Said main tanning agent can be combined with vegetable tannin extract, also can be combined with chrome for tanning leather, and can raise wet and thermal stabilizing of the finished leather and reduce dose of chrome by 30-40%.

The invention discloses novel oxazolidine, a preparation method, application, and mono-component polyurethane waterproof paint. The novel oxazolidine is named as 4-mehtyl-3-(2-phenylcarbinol)-1,3-oxazolidine. The novel oxazolidine is used as a latent curing agent of the mono-component polyurethane waterproof paint. During the production process of the waterproof paint, the novel oxazolidine is added into the raw materials, one naked hydroxy group of the novel oxazolidine will react with the polyurethane prepolymer formed by the raw materials, thus the novel oxazolidine is grafted to the polyurethane prepolymer, and the novel oxazolidine (latent curing agent) can be more evenly dispersed in the waterproof paint. If the waterproof paint is stored for a long time, the grafted novel oxazolidine will be dissolved out continuously, the stability of the waterproof paint is improved, the latent curing effect is improved, and avoided is the phenomenon that the latent curing agent is precipitated from the mono-component polyurethane waterproof paint or the latent curing agent aggregates in the waterproof paint. After the waterproof paint is used, the quality of the film formed by the waterproof paint is improved.

The invention relates to a coating, in particular to a spraying polyurea elastic coating. The spraying polyurea elastic coating is composed of a component A and a component B. The component A is prepared from, by mass, 55% to 65% of polyisocyanate and 35% to 45% of polyether polyol. The component B is prepared from, by mass, 45% to 55% of amine-terminated polyether, 34% to 45% of amine chain extenders, 5% to 10% of polyfunctionality oxazolidine, 0.5% to 1% of defoaming agents and 0.5% to 1% of dispersing agents. According to the spraying polyurea elastic coating, as the polyfunctionality oxazolidine is added into the dewatered amine-terminated polyether, hydroxyl terminated polyether and the amine chain extenders and can be firstly reacted with a small amount of moisture generated in the use process, the transport process and the use process to generate amino-and-hydroxyl-containing open-loop compounds, then the compounds are reacted with isocyanate groups of polyurea curing agents to be cured, carbon dioxide gas is not generated in the whole curing process, and the defect that a paint film is bubbly is well overcome.

The present invention is directed to processes for the preparation of N-(3R, 3aS, 6aR)-hexahydrofuro[2,3-b]furan-3-yl-oxycarbonyl-, (4S,5R)-4-[4-(2-methylthiazolo-4-methyloxy)-benzyl]-5-i-butyl-[(3,4-methylenedioxyphenyl)sulfonyl]-aminomethyl-2,2-dimethyl-oxazolidine.

Non-crystallizing oxazolidines as curing agents for polyisocyanates and polyurethanes. The curing agents are mixtures of at least one polyoxazolidine POU having at least two urethane groups and at least one polyoxazolidine POC having at least one carbonato group.

The invention discloses a star-like oxazolidine latent curing agent and a preparation method as well as an application of the latent curing agent. The latent curing agent is characterized by being prepared by the following steps of: adding 0.01-0.1 part of sodium ethoxide, 5-60 parts of tetraethyl 1,1,5,5-pentane-terminated tetraformate and 15-120 parts of 2,2-dimethyl-N-hydroxyethyl-1,3-oxazolidine into a reaction kettle, uniformly mixing the above raw materials, under the protection of nitrogen, increasing the temperature to 105-115 DEG C, carrying out reflux reaction for 2.5-3.5h, after the fractionation of ethanol is finished, increasing the temperature of a reaction solution to 115-125 DEG C to fractionate residual 2,2-dimethyl-N-hydroxyethyl-1,3-oxazolidine, when the amount of 2,2-dimethyl-N-hydroxyethyl-1,3-oxazolidine is not changed any more, stopping heating, dropwise adding 10-50 parts of butanone solution of p-toluenesulfonic acid at the concentration of 20-40% while stirring, carrying out reaction for 25-35min, neutralizing the reaction solution using acid until the pH (Potential of Hydrogen) is 7-7.5, adding 0.05-0.1 part of calcium oxide into the neutralized reaction solution, continuing the reaction for 0.5-1.5h, carrying out hot filtration at 75 DEG C to obtain 6-80 parts of thick semisolid tetra-2,2-dimethyl-N-hydroxyethyl-1,3-oxazolidinyl 1,1,5,5-pentane-terminated tetraformate.

This invention relates to a broad spectrum antimicrobial composition, effective against gram negative and gram positive bacteria and fungi, which comprises a synergistic composition comprising iodopropynyl butyl carbamate and a bicyclic hydroxymethyl oxazolidine containing less than 0.1% of free formaldehyde.

The invention discloses a coating graphite protective lubricant, and a preparation method and application method thereof. The coating graphite protective lubricant comprises the following ingredients by mass: 1.5-2 parts of monoethanolamine, 2.2-3 parts of sodium silicate, 1.8-2 parts of gelatins, 4.7-5 parts of sodium borate, 0.4-0.5 part of oxazolidine, 1.3-1.5 parts of sodium methylene bis-naphthalene sulfonate, 4.2-5 parts of ethylene-vinyl acetate copolymer, 0.8-1 part of crylic acid-2-ethylhexyl, 2.2-3 parts of diacetone alcohol, 14-15 parts of graphite and 60-62 parts of distilled water or deionized water. According to the invention, the coating graphite protective lubricant doesn't fall off, can't be oxidized, and has a good lubricating property and rejection capability.

The invention provides a new Vilanterol intermediate compound 2. According to the invention, primary amino is introduced into a compound 5 through Delepine reaction, then di-tert-butyl dicarbonate is employed for amino protection, and the strategy greatly improves the yield and atom utilization rate. On the other hand, cheap and easily available urotropin is adopted in the invention to lower the cost, thus being easy for industrial large-scale production. Compared with the prior art, the yield of the method involved in the invention is increased to 65% by three-step reaction, also use of expensive di-tert-butyl iminodicarboxylate and cesium carbonate is avoided, the cost is reduced, the operation is simple, and the conditions are mild. Therefore, the method is suitable for industrial preparation of Vilanterol and its key intermediate (5R)-5-(2, 2-dimethyl-4H-1, 3-benzodioxin-6-yl)-1, 3 oxazolidine-2-one. (formula of compound 2).

A catalyst curing system or hardener for resorcinolic resins, such as resorcinol-formaldehyde or phenol-resorcinol-formaldehyde resins including methylolurea. The methylolurea may be used in combination with oxazolidine in ratios ranging from 5:95 to 95:, by molar basis. The hardener crosslinks the resins which permits reduction or "fuming" of formaldehyde as well as control of gel times of the resulting adhesive. The hardener of the present invention if of particular utility in adhesives for use in the forest products industry.

The invention relates to an agricultural chemical compound herbicide for once preventing and killing weeds in paddy fields. The agricultural chemical compound herbicide is prepared by compounding fenoxaprop-p-ethyl and bensulfuron methyl, adding a compound safener of mefenpyr-diethyl and 3-benzenesulfonyl-oxazolidine-2-ketone and relative additives, not only expands a weed spectrum and once prevents and kills the weeds in the paddy fields, but also solves the hazard problem of the fenoxaprop-p-ethyl applied to the paddy fields and has wider prospects of market promotion and application.

The invention relates to a method for removing protective groups and preparing a dimethoxy taxane compound. The invention belongs to the technical field of medicines used for treating prostate cancer. According to the invention, an acid is dissolved in methanol; silica gel with a specification of 100-800 meshes is added to the solution, and the solution is sufficiently stirred under room temperature; the solution is dried by rotary evaporation, such that acid-activated silica gel is obtained; the acid-activated silica gel is dissolved in an organic solvent; a compound 3-Boc-2-p-methoxy phenyl-4-phenyl-(2R,4S,5R)-1,3-oxazolidine-5-carboxylate 4alpha-acetoxy-2alpha-benzoyloxy-5beta,20-epoxy-1beta-hydroxyl-9-oxygen-7beta,10beta-dimethoxy-11-taxadiene-13alpha ester is added to the solution; the mixture is continuously stirred, and is subject to a reaction; an obtained reaction liquid is processed through pump filtration; an obtained filtrate is dried by condensation, and is processed through silica gel column chromatography, such that the product dimethoxy taxane compound is obtained. According to the invention, the protective groups are removed in an acidic environment, such that the dimethoxy taxane compound is prepared. The method is advantaged in simple operation, suitability for industrialized productions, no by-product during the reaction process, improved reaction yield, and improved product purity.

The invention relates to linear polystyrene-supported (4S)-oxazolidine-2-benzimine which has the following structural formula, wherein m:n=1:1-4, and Mw=8300-14000. In the invention, (4S)-oxazolidine-2-benzimine is supported on linear polystyrene to prepare the linear polystyrene-supported (4S)-oxazolidine-2-benzimine as a chiral auxiliary reagent to induce asymmetric reaction into homogeneous reaction, and the reaction is rapid and convenient for on-line detection. The chiral auxiliary reagent not only reserves the high yield and the high stereoselectivity of the asymmetric reaction induced by the oxazolidine-2-benzimine as the chiral auxiliary reagent to obtain a chiral compound with high optical purity, bus also realize the recycling of the (4S)-oxazolidine-2-benzimine. The synthesized chiral compound with high optical purity is used as the precursor, the intermediate and the final product of medicines, agricultural chemicals, spices and functional materials.

The invention discloses a carbon dioxide one-pot method for directly preparing oxazolidine-2-one compounds. The method comprises the following steps: adding a catalytic amount of ionic liquid into epoxy compounds, carrying out reactions under a primary pressure of CO2, then adding aniline or aniline derivatives, and making the reactions going on so as to prepare the oxazolidine-2-one compounds. The carbon dioxide one-pot method has the advantages of no need to separate intermediate products, little using amount of catalyst, safe reaction operation, mild reaction conditions, no addition of any organic solvent in the reaction process, and environment-friendliness.

A preparation method for bisexual tanning agent takes 4,4' dihydroxy sulfobenzide, phenol sulfuric acid and methanol as the raw material to prepare a methanol condensate, takes diethanolamine and methanol as the raw material to prepare 3-ethoxyl oxazolidine, then to condensate the methanol condensate and 3-ethoxyl oxazolidine to prepare a bisexual tanning agent.

The invention relates to a high-molecular composite membrane, in particular to an antibacterial oxidation-resistant composite reverse osmosis membrane for water treatment. The antibacterial oxidation-resistant composite reverse osmosis membrane comprises a non-woven fabric layer, a porous supporting layer and a polyamide polymer desalination layer on the porous supporting layer, and is characterized by being prepared by the following steps of: (1) soaking the polyamide polymer desalination layer in a formaldehyde solution, taking out the polyamide polymer desalination layer and washing with purified water; (2) soaking the polyamide polymer desalination layer in a solution containing hydroxymethyl hydantoin or hydroxymethyl ethyleneurea or hydroxymethyl oxazolidine, and then drying; and (3) soaking the treated polyamide polymer desalination layer in a solution containing active chlorine, taking out and then washing with the purified water to obtain the antibacterial oxidation-resistant composite reverse osmosis membrane. The antibacterial oxidation-resistant composite reverse osmosis membrane disclosed by the invention further has the characteristics of easy preparation, high desalination rate and large water flux, and also has wide application.