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81 results about "1,4-Naphthoquinone" patented technology

1,4-Naphthoquinone or para-naphthoquinone is an organic compound derived from naphthalene. It forms volatile yellow triclinic crystals and has a sharp odor similar to benzoquinone. It is almost insoluble in cold water, slightly soluble in petroleum ether, and more soluble in polar organic solvents. In alkaline solutions it produces a reddish-brown color. Vitamin K is a derivative of 1,4-naphthoquinone. It is a planar molecule with one aromatic ring fused to a quinone subunit. It is an isomer of 1,2-naphthoquinone.

Cyanide-free silver plating solution additive

The invention relates to a cyanide-free silver plating solution additive which comprises the following components by ratio: 0.1-10g/ l of brightener, 5-10g/ l of leveling agent, 100-600g/ l of complexing agent and the balance of plasma water, wherein the brightener is one or mixture of more in nitrogen-containing compound, triazole, benzotriazole, 2-hydroxypyridine, pyridine, 22 dipyridyl, 1, 10-phenanthroline, triethylene tetramine and diethylene triamine according to any ratio; the leveling agent is one or mixture of more in aromatic hydrocarbon compounds, naphthalene, 1-methylnaphthalene, 1, 4-naphthoquinone and 1-naphthol according to any ratio; the complexing agent is one or mixture of more in disodium ethylenediamine tetraacetate, niacin, aminosulfonic acid and potassium pyrophosphate according to any ratio. The cyanide-free silver plating solution additive has the beneficial effects that the plating solution is stable, low in toxicity and good in dispersing ability; the obtained plating layer is bright and fine as well as good in binding force; the technology adopts the environment-friendly organic additive which does not contain heavy metal and sulfide; the plating layer is good in corrosion resistance. Furthermore, the cyanide-free silver plating solution additive can be directly used for parts such as brass, copper, chemical nickel and the like, preplating is not needed, and the binding force is also guaranteed.
Owner:HANGZHOU WIN WIN TECH CO LTD

Bi-component coating unsaturated polyester resin and preparation method thereof

The invention relates to a preparation method of a bi-component coating unsaturated polyester resin. The preparation method comprises the following steps of putting reactants and a first polymerization inhibitor accounting for 250 ppm-320 ppm of a total mass of the resin into a container to carry out polycondensation and dehydration reaction, wherein the reactants comprise a dihydric alcohol, allyl ether and unsaturated dicarboxylic acid or anhydride; cooling to a temperature of 120 DEG C-140 DEG C; adding the first polymerization inhibitor accounting for 40 ppm-80 ppm of the total mass of the resin; diluting by adding styrene; cooling to the temperature of 40-60 DEG C; and adding a second polymerization inhibitor accounting for 40 ppm-80 ppm of the total mass of the resin, wherein the second polymerization inhibitor is one or two of 1,4-naphthoquinone and p-benzoquinone. The bi-component coating unsaturated polyester resin prepared by the preparation method has a long resin activation period after an initiator is added; a drying time after the resin added with an accelerant and a resin added with the initiator are mixed is relatively short; and film-forming quality is high.
Owner:CHANGZHOU HUARI NEW MATERIAL

Preparation method of thiamine 1,4-naphthoquinone compound

The invention uses naphthoquinone, amine and mercaptan as raw materials, and provides a preparation method of a thiamine 1,4-naphthoquinone compound. The synthesis method has mild reaction conditions,oxygen is used as an oxidant under the condition of copper catalysis, and multiple thiamine 1,4-naphthoquinone compounds can be synthesized through a one-step reaction, and thus the method provides an efficient and practical synthesis method which is simple, convenient and efficient, cheap and easily-available in raw materials and catalysts, wide in adaptability, and has good application value and market prospect.
Owner:ZHENGZHOU UNIV

Method for preparing vitamin K3

The invention provides a method for preparing vitamin K3, and relates to vitamin K3. The method for preparing vitamin K3 with the chemical name of 2-methyl-1,4-naphthoquinone includes the following steps: dissolving 2-methylnaphthalene into a hydrocarbon solvent; adding sodium dodecyl sulfate and chromium ion oxidation liquid for an oxidation reaction; after completion of the reaction, purifying the reaction solution to obtain vitamin K3 with the chemical name of 2-methyl-1,4-naphthoquinone. The method for preparing vitamin K3 with the chemical name of 2-methyl-1,4-naphthoquinone sodium bisulfate includes the following steps: dissolving 2-methyl-1,4-naphthoquinone into a mixed solvent of water and ethyl alcohol; then adding sodium bisulfite for a sulfonation reaction; after completion of the reaction, purifying the reaction solution to obtain vitamin K3 with the chemical name of 2-methyl-1,4-naphthoquinone sodium bisulfate. According to the invention, the method is high in reaction selectivity, mild in reaction conditions, short in operation steps, green and environment-friendly, and stable in process; the product purity is 97% or above, and the total yield is 79% or above.
Owner:COMPREHENSIVE TECH SERVICE CENT OF QUANZHOU ENTRY EXIT INSPECTION & QUARANTINE BUREAU OF P R C

Novel crystalline forms of atovaquone

The present invention relates to two novel and stable crystalline forms of atovaquone, to processes for their preparation and to pharmaceutical compositions comprising them. The present invention also provides crystalline particles of atovaquone having a specific surface area of from about 0.7 m2 / g to about 4 m2 / g, methods for the manufacture of said crystalline particles and pharmaceutical compositions comprising said crystalline particles. The present invention further provides an improved and commercially viable process for preparation of atovaquone substantially free of its undesired isomeric impurity, namely cis-2-[4-(4-chlorophenyl)cyclohexyl]-3-hydroxy-1,4-naphthoquinone.
Owner:HETERO DRUGS LTD

Synthesis method of compounds of 5-benzoyl-1, 4-naphthaquinone with similar gossypol effect

The invention discloses a practical synthesis method of compounds of 5-benzoyl-1, 4-naphthaquinone with a similar gossypol effect. The practical synthesis method comprises the steps that: a) malonic acid and acrolein take condensation reaction to obtain a compound of pentadienoic acid shown in the formula I; b) the compound shown in the formula I takes reaction with p-benzoquinone to obtain a compound of cis-5, 8-diketone-1,4,6,7,9,10-hexahydronaphthalene-beta-carboxylic acid shown in the formula II; c) the compound shown in the formula II is subjected to methylation to obtain a compound of 5,8-dimethoxy-1,4-dihydronaphthalene-1-carboxylic acid-methyl ester shown in the formula III; d) the compound shown in the formula III takes dehydro-aromatization reaction to obtain a compound of 5,8-dimethoxy naphthoate shown in the formula IV; e) the compound shown in the formula IV is hydrolyzed to obtain a compound of 5,8-dimethoxy naphthoyl naphthoic acid shown in the formula V; f) the compound shown in the formula V is subjected to chlorination to obtain a compound of 5,8-dimethoxy naphthoyl chloride shown in the formula VI; g) the compound shown in the formula VI and benzene are subjected to Friedel-Crafts acidylation to obtain a compound of 5-benzoyl-1,4-dimethoxy naphthalene shown in the formula VII; and h) the compound shown in the formula VII is oxidized to obtain a compound of 5-benzoyl-1,4-naphthoquinone shown in the formula VIII.
Owner:SOUTHEAST UNIV

Anti-allergic agent

ActiveUS20090281187A1Potent degranulation-inhibiting effectBiocideKetone active ingredientsVitamin K3BULK ACTIVE INGREDIENT
The inventors have found that vitamin K3 and vitamin K5 which may be used in pharmaceuticals and foods or ACNQ, DHNA, or the like which can stimulate the growth of bifidobacteria can inhibit degranulation of basophil-like cells, exhibit a potent degranulation-inhibiting effect, and are useful anti-allergic agents or foods. The present invention provides an anti-allergic agent containing, as an active ingredient, one or more species selected from among 2-amino-3-carboxy-1,4-naphthoquinone, 1,4-dihydroxy-2-naphthoic acid, 1,4-naphthoquinone, 4-amino-2-methyl-1-naphthol, 2-methyl-1,4-naphthoquinone, 2-amino-3-chloro-1,4-naphthoquinone, and a salt thereof.
Owner:MEIJI CO LTD
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