38 results about "Quercetin derivatives" patented technology

Methods and compositions are described that comprise pyrone analogs such as flavonoids and cyclodextrins including quercetin and quercetin derivatives and sulfoalkyl ether cyclodextrins. In some cases the compounds of the invention are administered with a therapeutic agent such as an analgesic. In some cases, treatment with the compositions of the invention can result in the modulation of central nervous system and/or fetal effects of substances. Methods and compositions are described for the modulation of efflux transporter activity to increase the efflux of drugs and other compositions out of a physiological compartment and into an external environment. In particular, the methods and compositions disclosed herein provide for the increase of efflux transporter activity at blood-brain, blood-CSF and placental-maternal barriers to increase the efflux of drugs and other compositions from physiological compartments, including central nervous system and fetal compartments.

The present invention is a hair treatment agent comprising a combination of dihydroquercetin and/or a dihydroquercetin derivative with at least one amino acid. A preferred hair treatment agent comprises a combination of dihydroquercetin (taxifolin) with a six-amino acid mixture consisting of taurine, proline, valine, arginine, lysine, and glycine. The inventive hair treatment agent positively influences the natural pigmentation process of skin and skin appendages, such as for example, stimulating melanogenesis and pigmentation of hair, preventing and reducing the graying of hair, and repigmenting gray hair.

The invention provides quercetin derivatives. The chemical structural general formulas of the quercetin derivative is as shown in the specification; and the synthetic method of the quercetin derivative comprises the following steps: (1) taking a carbonate and the like as the acid-binding agents and potassium iodide as the catalyst, and reacting the quercetin with a halogen substitute of fatty acid ethyl ester; (2) separating and purifying by silica gelcolumn chromatography, and collecting the same components to obtain three yellow powdery compounds: quercetin ester derivatives; and (3) taking the synthesized derivatives as the reactants, respectively, adding NaOH aqueous solution and taking polyethylene glycol as the phase transfer catalyst; separating and purifying by silica gelcolumn chromatography, and collecting the same components to obtain quercetin carboxylic acid derivatives, respectively. The synthetic method of the series quercetin derivatives provided by the invention is simple and easy to operate; the yield of each product is high; and the series quercetin derivatives are remarkably improved in both water solubility and lipid solubility compared with the quercetin.

The invention relates to hydroxyethylated meletin derivative with general formula (I), and the R1, R2, R3, R4, R5 are H or -CH2CH2OH, and at least one of R1, R2, R3, R4, R5 is -CH2CH2OH, but R1, R2 are not H, and R3, R4, R5 are -CH2CH2OH. The invention also relates to method for preparing said compound, comprising dissolving meletin in basic solution, adding epoxyethane or chlorethanol, stirring, neutralizing with acid to be neutral, getting coarse product; removing salt with one methodof normal chromatogram, chromatogram, hyperfiltration, ion exchange, electrodialysis and hyperfiltration; drying and getting yellow or amber-yellow powder hydroxyethylated meletin derivative. The product is widely used in preparing drug, cosmetics, health products and foodstuff.

The invention discloses a quercetin derivative and a preparation method thereof and belongs to the field of medicine synthesis. In order to solve the problems that quercetin is poor in water solubility, low in bioavailability and the like in the prior art, the quercetin derivative is provided, and the obtained quercetin derivative has the lipid solubility far better than quercetin, has greatly improved bioavailability and can be used for treating cardiovascular and cerebrovascular diseases and resisting and preventing cancer. The invention also aims to provide a method for synthesizing the quercetin derivative. The quercetin is used for protecting hydroxyl, a substitution reaction and a hydrogeneration reaction are performed for preparation of the quercetin derivative, and the high-purityquercetin derivative is prepared. The natural quercetin is chemically modified and subjected to a substitution reaction at a 5-OH hydroxyl site, thereby improving the water solubility and lipid solubility of the quercetin and improving the bioavailability. The method adopts a simple principle, the product yield is high and is 37%-57%, the purity reaches 96%-98%, and Rf ranges from 0.2 to 0.5.

The invention discloses an extract of an active anti-fatigue part of okra, and a preparation method and application thereof. The extract of the active anti-fatigue part of okra uses total polyphenols as a main active anti-fatigue component, wherein the total polyphenols account for 11.79 to 23.34% of the total mass of the extract of active anti-fatigue part and mainly comprise catechin derivatives and quercetin derivatives, and the quercetin derivatives are mainly composed of quercetin-3-O-gentiobioside, quercetin-3-O-glucose-xyloside, isoquercitrin, quercetin-3-O-malonyl-glucoside, rutin and quercetin. The extract of the active anti-fatigue part of okra provided by the invention can substantially prolong the load swimming time of mice, eliminate lactic acid accumulation after sports, reduce the content of serum urea nitrogen, increase hepatic glycogen and improve the antioxidation capability of mice in a stress state, and has substantial anti-fatigue effect.

The invention discloses a quercetin derivative and a preparation method and application thereof. The preparation method comprises the following steps: firstly using dichlorodiphenylmethane to protect quercetin o-diphenol hydroxyl, combining a benzyl protection group to obtain the selectively protected quercetin derivative, and then independently reacting with dimethyl sulfate, diethyl sulfate, allyl bromide, paratoluensulfonyl chloride and acetic anhydride respectively to generate corresponding quercetin derivatives. All of the prepared derivative compounds have NRK-49F proliferation activity inhibition superior to that of quercetin. The quercetin derivatives 20a-1, 14a-1 and 23d-1 compositely replaced by methyl and p-tosyl have higher inhibition NRK-49F proliferation activity, and the inhibition ratio respectively reaches 86.33%, 78.04% and 75.91%. Thus, the currently obtained quercetin derivative compounds have obvious inhibition effect on kidney fibroblast NRK-49F proliferation.

The invention discloses a quercetin derivative and a preparation method and application thereof. The preparation method comprises the following steps of firstly, mixing quercetin, formaldehyde and ammonia to prepare Mannich alkaline of the quercein; reacting with 2-oxazolidine (thio)one and SOCl2; protecting phenolic hydroxyl of the quercetin, oxidizing by NaNO2, and removing protecting groups, so as to obtain the quercetin derivative. The prepared quercetin derivative can be used for inhibiting brain tumors and central nervous system tumors via blood brain barrier.

The invention discloses application of a compound (QB) shown in a formula I in preparation of medicines for prevention and/or treatment. The MTT experiment displays that the proliferation inhibition effects of the compound QB on the four tumor cells, such as human esophageal squamous carcinoma cell EC109, the human esophageal squamous carcinoma cell EC9706, the human gastric carcinoma cell SGC7901 and mouse melanoma cell B16-F10, are obviously superior to those of quercetin. The inhibition effect of (IC50=5.201mu g/mL) on the EC109 cells is equivalent to that of fluorouracil 5-FU(IC50=5.426mu g/mL), the toxic or side effect is relatively small, and the compound is a potential antitumor candidate compound.

The invention relates to arylethanolamine quercetin derivatives or pharmaceutically acceptable salts thereof. The derivatives comprise stereoisomers or tautomers thereof. The method for preparing the derivatives comprises the following steps: preparing Mannich base of quercetin from quercetin, formaldehyde and ammonia, and reacting with aryl ethylene oxide, thereby obtaining the arylethanolamine quercetin derivative. The arylethanolamine quercetin derivatives have the effects of treating asthma.

The invention relates to a nitrogen mustard quercetin derivative comprising a stereisomer or a tautomer, a preparation method of the nitrogen mustard quercetin derivative, a medicinal composition taking the derivative as an active component, and application of the medicine to cancer treatment. The preparation method of the derivative comprises the following steps: preparing Mannich alkali of quercetin from the quercetin, formaldehyde and chlorethamin, and performing reaction on the Mannich alkali and substituted phosphoramidic dichloride to prepare the nitrogen mustard quercetin derivative. The nitrogen mustard quercetin derivative has an anti-tumor effect.

This invention relates to quercetin derivative, its preparation, and a pharmaceutical combination, as well as their medical uses for the prevention or treatment of diseases related to 5HT_1A receptor or neuron cell damages, including Alzeheimer's disease, drug or alcohol dependence, sleep disorders or panic state; and for delaying senility, improving learning and memory, preventing and treatment of neuron cell damages caused by various kinds of cerebral damages.

The invention provides a prunus mume leaf extract, a preparation method and application thereof. The prunus mume leaf extract is prepared from, by weight, 0.5-10.0% of quercetin, 0.5-5.0% of isorhamnetin, 50.0-70.0% of plant glucoside, 5-10% of quercetin derivative and isorhamnetin derivative and inevitable impurities. Prunus mume leaves are extracted through the method combining ethanol extraction and ultrasonic extraction, ethanol at 40-65 DEG C is used for extraction so that solubility of quercetin and isorhamnetin can be improved, the dissolving-out speed increased due to ultrasonic extraction, and accordingly dissolution is more thorough. The prunus mume leaf extract is a pure natural component and has the functions of reducing ultraviolet radiation, preventing oxidation and the like, and accordingly skin cells are protected. The extract can also have the function of preventing skin acne generation, reduces pigmentation, inhibits stain generation, and makes skin white and bright.

The invention relates to bola type quercetin derivatives and a preparation method thereof. A bola type amphiphilic molecule is formed by connecting two polar head groups by using a hydrophobic chain; and unique natures such as better stability and compatibility in a plasma membrane are given to the bola type amphiphilic molecule through the special structure. The bola type quercetin derivatives shown as general formulas I-V are developed by utilizing bola type characteristics to increase the water solubility and the bioavailability of the derivatives; meanwhile, proved by research results, compared with non-bola type quercetin lipid derivatives, the bola type quercetin derivatives are capable of better inhibiting the growth activity of tumor cells; the bola type quercetin derivatives are transformed into nanometer drugs through micromolecule self-assembly on the basis of the structure to improve the physicochemical property of compounds; the ability of targeting focal tissues is enhanced and the damage of the drugs to normal tissues and cells is reduced; and R and n in the general formulas are defined as the claim.

The invention discloses an application of 3-O-methyl quercetin to resisting oxidation or reducing blood sugar, and belongs to the technical field of pharmaceuticals. The invention aims to provide a quercetin derivative-3-O-methyl quercetin having activity of resisting oxidation and reducing blood sugar, and an application of the quercetin derivative-3-O-methyl quercetin as an alpha-glucosidase inhibitor and an antioxidant to preparation of medicines and/or health-care products for treating diabetes. The 3-O-methyl quercetin disclosed by the invention has favorable alpha-glucosidase restrainingactivity, and besides, has the activity of resisting oxidation. The in vitro alpha-glucosidase restraining experiment proves that the 3-O-methyl quercetin disclosed by the invention has significant restraining activity on the alpha-glucosidase, and the IC50 value for restraining the alpha-glucosidase is 1.38+/-0.01 [mu]g/mL which is significantly better than that of quercetin.

The invention discloses a composition for inhibiting alpha-glucosidase and application of the composition and belongs to the technical field of natural active compounds. The composition disclosed by the invention comprises daidzein and a quercetin derivative, wherein the quercetin derivative is dihydroquercetin or 3-O-methyl quercetin; wherein the mass ratio of the daidzein to the dihydroquercetin is (8: 25)-(10: 25); and the mass ratio of the daidzein to the 3-O-methyl quercetin is (8: 2)-(8: 4). The composition disclosed by the invention has an obvious synergistic effect of inhibiting alpha-glucosidase, the effect of the composition is superior to that of single use of a flavone compound, the dosage of medicines can be reduced, and the occurrence of drug resistance is reduced.

The present invention provides novel Quercetin derivatives of formula (I) and pharmaceutically acceptable salts, hydrates, and solvates thereof,

wherein R₁ is hydrogen, benzyl or substituted benzyl; R₂ is hydrogen, benzyl or substituted benzyl, linear or branched (C₁-C₆) alkyl, substituted alkyl, aryl, substituted aryl, heterocycle and substituted heterocycle, useful for treatment of various disorders including cancer, multi-drug resistant cancers, viral infections etc. The invention also provides a process for the preparation of compounds of formula (I) and pharmaceutical compositions comprising the same.