The present disclosure provides a preparation method of dihydroquercetin, belonging to the field of synthesis of drugs. The method includes steps of: adjusting reaction solvent water to be alkaline with an alkalizing reagent, to obtain an alkaline aqueous solution; dissolving quercetin dihydrate in the alkaline aqueous solution, and adding a sulfite binary combined reducing agent to carry out reduction reaction, to obtain an endpoint reduction reaction solution; diluting the endpoint reduction reaction solution with water, and then acidizing, aging, and filtering the resultant to obtain a filtrate and a filter cake; subjecting the filtrate to extraction, washing, drying, and vacuum concentration to obtain a concentrated crude product; and repeatedly crystallizing the concentrated crude product to obtain dihydroquercetin. The preparation method of the present disclosure has readily available raw materials, a simple process, and low production costs, and is particularly suitable for industrial production.

The present disclosure provides a preparation method of dihydroquercetin, belonging to the field of synthesis of drugs. The method includes steps of: adjusting reaction solvent water to be alkaline with an alkalizing reagent, to obtain an alkaline aqueous solution; dissolving quercetin dihydrate in the alkaline aqueous solution, and adding a sulfite binary combined reducing agent to carry out reduction reaction, to obtain an endpoint reduction reaction solution; diluting the endpoint reduction reaction solution with water, and then acidizing, aging, and filtering the resultant to obtain a filtrate and a filter cake; subjecting the filtrate to extraction, washing, drying, and vacuum concentration to obtain a concentrated crude product; and repeatedly crystallizing the concentrated crude product to obtain dihydroquercetin. The preparation method of the present disclosure has readily available raw materials, a simple process, and low production costs, and is particularly suitable for industrial production.

The present invention provides a sirtuin activator with an active component composed of black ginger or a black ginger extract, which is easily obtainable, extremely safe, and eaten from old. The present invention further provides a sirtuin activator with an active component of polyalkoxyflavonoid compound represented by general formula (I) and having a sirtuin activation effect that is 10 folds that of resveratrol or higher: ##STR00001## wherein, R.sub.1 to R.sub.7 are each independently a hydrogen atom, a hydroxyl group, or a C1 to C6 lower alkoxy group.

The present invention provides a sirtuin activator with an active component composed of black ginger or a black ginger extract, which is easily obtainable, extremely safe, and eaten from old. The present invention further provides a sirtuin activator with an active component of polyalkoxyflavonoid compound represented by general formula (I) and having a sirtuin activation effect that is 10 folds that of resveratrol or higher: ##STR00001## wherein, R.sub.1 to R.sub.7 are each independently a hydrogen atom, a hydroxyl group, or a C1 to C6 lower alkoxy group.

This invention relates to a flavonoid composition that includes eriocitrin. The flavonoid may be included in a complex with other bioflavonoids. The composition may also include neoeriocitrin. This invention also relates to methods of using the composition, including for reducing IL-6 or MCP-1 treating inflammation, and treating symptoms of metabolic syndrome.

This invention relates to a flavonoid composition that includes eriocitrin. The flavonoid may be included in a complex with other bioflavonoids. The composition may also include neoeriocitrin. This invention also relates to methods of using the composition, including for reducing IL-6 or MCP-1 treating inflammation, and treating symptoms of metabolic syndrome.

The present application describes process for preparing an ortho-allylated hydroxy aryl compounds such as compounds of Formula (I) by reacting an allylic alcohol with a hydroxy aryl compound in the presence of aluminum compound selected from alumina and aluminum alkoxides and in a non-protic solvent wherein at least one carbon atom ortho to the hydroxy group in the hydroxy aryl compound is unsubstituted. The present application also includes compounds of Formula (I).

##STR00001##

The present application describes process for preparing an ortho-allylated hydroxy aryl compounds such as compounds of Formula (I) by reacting an allylic alcohol with a hydroxy aryl compound in the presence of aluminum compound selected from alumina and aluminum alkoxides and in a non-protic solvent wherein at least one carbon atom ortho to the hydroxy group in the hydroxy aryl compound is unsubstituted. The present application also includes compounds of Formula (I).

##STR00001##

The present disclosure provides a preparation method of dihydroquercetin, belonging to the field of synthesis of drugs. The method includes steps of: adjusting reaction solvent water to be alkaline with an alkalizing reagent, to obtain an alkaline aqueous solution; dissolving quercetin dihydrate in the alkaline aqueous solution, and adding a sulfite binary combined reducing agent to carry out reduction reaction, to obtain an endpoint reduction reaction solution; diluting the endpoint reduction reaction solution with water, and then acidizing, aging, and filtering the resultant to obtain a filtrate and a filter cake; subjecting the filtrate to extraction, washing, drying, and vacuum concentration to obtain a concentrated crude product; and repeatedly crystallizing the concentrated crude product to obtain dihydroquercetin. The preparation method of the present disclosure has readily available raw materials, a simple process, and low production costs, and is particularly suitable for industrial production.

The present disclosure provides a preparation method of dihydroquercetin, belonging to the field of synthesis of drugs. The method includes steps of: adjusting reaction solvent water to be alkaline with an alkalizing reagent, to obtain an alkaline aqueous solution; dissolving quercetin dihydrate in the alkaline aqueous solution, and adding a sulfite binary combined reducing agent to carry out reduction reaction, to obtain an endpoint reduction reaction solution; diluting the endpoint reduction reaction solution with water, and then acidizing, aging, and filtering the resultant to obtain a filtrate and a filter cake; subjecting the filtrate to extraction, washing, drying, and vacuum concentration to obtain a concentrated crude product; and repeatedly crystallizing the concentrated crude product to obtain dihydroquercetin. The preparation method of the present disclosure has readily available raw materials, a simple process, and low production costs, and is particularly suitable for industrial production.