WO2009064485A1

WO2009064485A1 - Antioxidant flavonoid derivatives

Info

Publication number: WO2009064485A1
Application number: PCT/US2008/012826
Authority: WO
Inventors: Koji Nakanishi; Emiko Yanase; Janet R. Sparrow
Original assignee: Trustees Of Columbia University In The City Of New York
Priority date: 2007-11-16
Filing date: 2008-11-14
Publication date: 2009-05-22

Abstract

The present invention relates to antioxidant flavonoids, compositions containing such antioxidant flavonoids, methods for using such antioxidant flavonoids to treat, e.g., AMD, and methods for making such antioxidant flavonoids. Also provided are methods for ameliorating A2E photooxidation, especially in cells and mammals, particularly, humans.

Description

ANTIOXIDANT FLAVONOID DERIVATIVES

FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

[0001] The invention was made with government support under grant number

NIH GM 36564 awarded by the National Institutes of Health. The government may have certain rights in the invention.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] The present application claims the benefit of U.S. provisional patent application no. 61/003,464, filed 16 November 2007, which is incorporated by reference as if recited in full herein.

FIELD OF THE INVENTION

[0003] The present invention relates to antioxidant flavonoids, compositions containing such compounds, and methods of using such compounds and compositions to prevent, treat or ameliorate macular degeneration and other diseases or conditions associated with oxidative damage. The present invention also relates to methods of making such antioxidant flavonoids. More particularly, the present invention relates to methods of making an antioxidant flavonoid by, e.g., reacting quercetin or a quercetin glycoside under conditions sufficient to link an antioxidant to the quercetin or quercetin glycoside. Methods for modulating photooxidation of A2E in cells (of, e.g., the eye, particularly retinal cells) and mammals, such as e.g., humans, are also provided. BACKGROUND OF THE INVENTION

[0004] The macula is located at the back of the eye in the center of the retina.

When the millions of cells in this light-sensitive, multilayer tissue deteriorate central vision is lost along with the ability to perform tasks such as reading, writing, driving, and seeing color. This "macular degeneration" principally affects the elderly and occurs in three out of ten people over the age of 75. In younger populations, macular degeneration is found in individuals with genetic disorders, such as Stargardt, Vitelliform or Best (VMD), Sorsby's Fundus Dystrophy and Malattia Leventinese (Doyne Honeycomb or Dominant Radial Drusen) (1 ). Stargardt Disease is the most common form of inherited juvenile macular degeneration, affecting about 1 in 10,000 children.

[0005] Age related macular degeneration (AMD) is the leading cause of blindness in the United States, leads to photoreceptor cell death and loss of vision. There are no therapies currently available for genetic or dry (non-neovascular) age related macular degeneration. Vitamin supplements and diet changes, such as low fat diets, have been shown to slow disease progression in some clinical studies. However, for the majority of patients, diagnosis is followed by the progressive loss of central vision.

[0006] The above listed macular dystrophies are all marked by the accumulation of lipofuscin, fluorescent deposits, in the retinal pigment epithelium (RPE) cell layer (2-5). Lipofuscin is a mixture of chromophores, including A2E, which is derived from two molecules of vitamin A aldehyde and one molecule of ethanolamine. A2E have been shown to cause RPE cell death, which is thought to lead to photoreceptor cell degeneration and vision loss (6, 7). [0007] Photooxidation of A2E is linked to RPE cell damage. RPE cells are particularly susceptible to damage by wavelengths within the blue region of the visible spectrum (8, 9). A2E also has a strong absorption in the blue region, and blue-light irradiation of A2E leads to the photooxidation of A2E such that oxygens are added to carbon-carbon double bonds along the side arms of the molecule (10, 11 ). Furthermore, A2E-loaded RPE cells have increased susceptibility to blue-light damage (12). Blue-light irradiation was also found to enhance A2E-mediated damage to mitochondria (13).

[0008] A2E is believed to mediate light damage via various mechanisms.

First, A2E can photochemically initiate free-radical reactions (14) and can produce superoxide and peroxyl radicals called reactive oxygen species (ROS) (15). In addition, blue light can chemically modify A2E molecules, and these chemically modified A2E molecules may subsequently be toxic in the dark, because photo- oxidized A2E molecules damage RPE cells in the dark (16).

[0009] Plant-derived anthocyanins may protect against A2E photo-oxidation in retinal pigment epithelial cells (17). Anthocyanins are present in fruits such as blueberries, which contain the common flower petal pigment and which are marketed as herbal remedies for AMD. However, anthocyanin-derived antioxidants are not commercially practical because, inter alia, the anthocyanins are difficult to secure in large quantities and are unstable, and hence not suitable as starting compounds for various chemical modification and derivatization reactions. [0010] In view of the foregoing, oxidation of A2E in RPE cells may contribute to a decline in cell function followed by vision loss. Accordingly, it would be advantageous to prevent or to provide treatments for AMD and other forms of macular degeneration. In particular, it would be advantageous to provide new chemically stable and readily synthesized compounds and compositions that may be used to alleviate the effects of diseases or conditions associated with oxidative damage, e.g., by treating, preventing or ameliorating the oxidation damage to A2E molecules in the RPE cells of the retina.

SUMMARY OF THE INVENTION

[0011] One embodiment of the present invention is a method for making an antioxidant flavonoid comprising reacting quercetin or a quercetin glycoside under conditions sufficient to link an antioxidant to the quercetin or quercetin glycoside. [0012] Another embodiment of the invention is a method for making an antioxidant flavonoid comprising:

(a) reacting a compound of formula (I):

(i)

wherein Ri is OH or a glycoside under conditions sufficient to link an antioxidant to the compound of formula (I).

[0013] A further embodiment of the present invention is a method for treating age-related macular degeneration (AMD) comprising administering to a patient in need thereof an amount of an antioxidant flavonoid made according to the any of the methods of the present invention.

[0014] Yet another embodiment of the invention is an antioxidant flavonoid of the formula Il or III: (II) (III)

wherein

R₂, R₃, R4, R₅, Rβ_> and R₇ are independently selected from H and an antioxidant, with the proviso that R2, R₃, R4, Rs, Re, and R₇ are not all H.

[0015] Yet another embodiment of the invention is a pharmaceutical composition comprising a carrier and an antioxidant flavonoid according to the present invention, including at least one compound of formula I, II, or III.

[0016] Yet another embodiment of the invention is a compound having a structure selected from the group consisting of:

or an enantiomer, optical isomer, diastereomer, N-oxide, crystalline form, hydrate, or pharmaceutically acceptable salt thereof.

[0017] Yet another embodiment of the invention is a pharmaceutical composition comprising a carrier and compound selected from the group consisting of:

[0018] A further embodiment of the invention is a method for treating age- related macular degeneration (AMD) comprising administering to a patient in need thereof an amount of a pharmaceutical composition according to the present invention, which amount is sufficient to reduce oxidation of A2E in the patient's retina.

[0019] Another embodiment of the invention is a method of modulating photooxidation of A2E. This method comprises providing a photooxidation reducing amount of a compound of formula I, II, or III to, e.g., a cell or a patient, which may be a mammal, preferably a human.

BRIEF DESCRIPTION OF THE DRAWINGS

[0020] FIG. 1 is a reaction scheme showing the synthesis of quercetin-3- curcumin (compound 8).

[0021] FIG. 2 is a reaction scheme showing the synthesis of quercetin-3- caffeic acid (compound 15).

[0022] FIG. 3 is a reaction scheme showing the synthesis of quercetin-3, 7-di- caffeic acid (compound 16).

[0023] FIG. 4 is a reaction scheme showing the synthesis of quercetin-7- caffeic acid (compound 17).

[0024] FIG. 5 is a reaction scheme showing the synthesis of quercetin- glucoside-caffeic acid (compound 22). [0025] FIG. 6 is a reaction scheme showing the synthesis of quercetin- xanthophyll (compound 19).

[0026] FIG. 7 is a bar graph showing the amount of A2E present in various samples treated with quercetin conjugates or curcumin I (control) after illumination at 430 nm (as measured by reverse phase HPLC) expressed as a percentage of A2E present in the sample before illumination at 430 nm.

DETAILED DESCRIPTION OF THE INVENTION

[0027] One embodiment of the present invention is a method of making an antioxidant flavonoid. In one aspect of this embodiment, the method includes reacting quercetin (compound 1 ) or a quercetin glycoside (e.g., compound 21 ) under conditions sufficient to link an antioxidant to the quercetin or quercetin glycoside. In the present invention, "link" or "linking" preferably means covalently bonded. [0028] In this embodiment, the reacting step includes: (a) contacting quercetin (1 ) with Ph₂CCI₂ under conditions sufficient to form compound 2:

; (b) contacting compound 2 with N- (benzyloxycarbonyl)-3-bromopropylamine under conditions sufficient to form compound 3:

; (c) contacting compound 3 with acetone and TFA

under conditions sufficient to form compound 4:

(d) contacting curcumin I with ethyl 4-bromobutyrate under conditions sufficient to form compound 6:

; (e) contacting compound 6 with acetic anhydride followed by N-hydroxysuccinimide hydrochloride under conditions sufficient to form compound 7:

; (f) contacting compound 4 with compound 7 under conditions sufficient to form compound 8a:

; and (g) hydrolyzing compound 8a under conditions sufficient to form compound 8:

Preferably, compound 8 is purified from the reaction mixture. [0029] In another aspect of this method, the reacting step comprises:

(a) contacting 3',4',7-tribenzylquercetin (compound 23) with 4-(Boc- amino)butyl bromide and potassium carbonate under conditions sufficient to form compound 24:

(b) hydrogenating compound 24 over 10% Pd-C under an atmospheric pressure of hydrogen under conditions sufficient to form compound 25:

(c) contacting caffeic acid (compound 9) in pyridine with acetic anhydride under conditions sufficient to form compound 13:

(d) contacting compound 13 in DMF with N-hydroxy-succinimide hydrochloride and N-Ethyl-N'-(3-dimethyl-aminopropyl)-carbodiimide hydrochloride (WSC) under conditions sufficient to form compound 14:

¹⁴ ; and

(e) contacting compound 25 sequentially with HBr/AcOH followed by

< triethylamine and compound 14 followed by a solution of NH₄OAc under conditions sufficient to form compound 26:

[0030] In a further aspect of this method, the reacting step comprises: (a) contacting curcumin I sequentially with potassium carbonate and ethyl 4-bromobutyrate followed by NaOH and dioxane, followed by AC₂O and pyrimidine under conditions sufficient to form compound 6:

(b) contacting compound 6 with N-hydroxy-succinimide hydrochloride and N-Ethyl-N'-(3-dimethyl-aminopropyl)-carbodiimide hydrochloride (WSC) under conditions sufficient to form compound 7:

(c) contacting compound 25 sequentially with HBr/AcOH followed by triethylamine and compound 7 followed by a solution of NH₄OAc under conditions sufficient to form compound 27:

[0031] In both of the foregoing aspects, compounds 26 and 27 may be further purified by known methods in the art or as described further in the examples below. [0032] In another embodiment of the invention, a method is provided for making an antioxidant flavonoid. This method includes reacting a compound of formula (I):

(I)

wherein R₁ is OH or a glycoside under conditions sufficient to link an antioxidant to the compound of formula (I), particularly, e.g., at the moiety pendant at Ri. [0033] In the present invention, the antioxidant may be any antioxidant, currently known or to be discovered, that is effective to provide protection to a subject in need thereof from oxidation, e.g., diseases and conditions associated with oxidation. Representative non-limiting examples of antioxidants according to the invention include curcumin I, caffeic acid, carotenoids, and derivatives thereof. In the present invention, carotenoids include both xanthophylls and carotenes. [0034] Other non-limiting examples of antioxidants according to the present invention include amino acids and derivatives thereof, imidazoles and derivatives thereof, urocanic acid, D.L-carnosine, D-carnosine, L-carnosine, anserine, alpha- carotene, beta-carotene, lycopene, chlorogenic acid and derivatives thereof, lipoic acid and derivatives thereof, dihydrolipoic acid, aurothioglucose, thiols and salts thereof, propylthiouracil, thioredoxin, glutathione, cysteine, cystine, cystamine, glycosyl, N-acetyl, methyl, ethyl, propyl, amyl, butyl and lauryl, palmitoyl, oleyl, gamma-linoleyl, cholesteryl and glyceryl esters of cystamine, dilauryl thiodipropionate, distearyl thiodipropionate, thiodipropionic acid and derivatives thereof, sulfoximine compounds, buthionine sulfoximines, homocysteine sulfoximine, buthionine sulfones, penta-, hexa-, and heptathionine sulfoximines, chelating agents, alpha-hydroxy fatty acids, palmitic acid, phytic acid, lactoferrin, alpha-hydroxy acids, citric acid, lactic acid, malic acid, humic acid, bile acid, bile extracts, bilirubin, biliverdin, EDTA, EGTA and derivatives thereof, unsaturated fatty acids and derivatives thereof, gamma-linolenic acid, linoleic acid, oleic acid, folic acid and derivatives thereof, ubiquinone, ubiquinol and derivatives thereof, vitamin C and derivatives thereof, ascorbyl palmitate, Mg ascorbyl phosphate, ascorbyl acetate, tocopherols and derivatives thereof, vitamin E acetate, vitamin A and derivatives thereof, vitamin A palmitate, coniferyl benzoate of benzoin, rutinic acid and derivatives thereof, alpha-glycosylrutin, ferulic acid, furfurylideneglucitol, carnosine, butylhydroxytoluene, butylhydroxyanisole, nordihydroguaiacic acid, nordihydroguaiaretic acid, trihydroxybutyrophenone, uric acid and derivatives thereof, mannose and derivatives thereof, zinc and derivatives thereof, ZnO, ZnSO4, selenium and derivatives thereof, selenomethionine, stilbenes and derivatives thereof, stilbene oxide, trans-stilbene oxide, and combinations thereof. [0035] Preferably, the antioxidant flavonoid formed by this method is purified.

The purification step or steps may be any conventionally know purification step, including those set forth in the examples.

[0036] In the present invention, the glycone (sugar) portion of the glycoside may be any physiologically acceptable sugar molecule that can be incorporated with an aglycone to form a glycoside and participate in the reactions described herein to form the antioxidant flavonoids of the present invention. For example, the glycone (sugar) portion of the glycoside may be selected from aldopentose, aldohexose, aldotetrose, ketopentose and ketohexose. Preferably, the glycone (sugar) portion of the glycoside is selected from ribose, arabinose, xylose, lyose; allose, altrose, glucose, mannose, gulose, idose, galactose, talose, fucose, rhamnose, ribulose, xylulose, erythrose, threose, psicose, fructose, sorbose, and tagatose. [0037] Preferably, in this embodiment, the antioxidant flavonoid is:

[0038] In another embodiment of the invention, there is provided a method for treating age-related macular degeneration (AMD). This method includes administering to a patient in need thereof an amount of an antioxidant flavonoid made according to any of the methods of the present invention. In this method, the antioxidant flavonoid is as previously defined.

[0039] In another embodiment of the invention, there is provided an antioxidant flavonoid of the formula Il or III:

(») (III)

wherein R₂, Rβ, R₄, R₅. Rβ. and R₇ are independently selected from H and an antioxidant, with the proviso that R₂, R₃, R₄, R₅, Re. and R₇ are not all H.

[0040] In this embodiment, the antioxidant is preferably selected from curcumin I, caffeic acid, carotenoids, and derivatives thereof. The carotenoid may be any carotenoid, such as for example, a xanthophyll or a carotene. [0041] Other antioxidants may also be used in this embodiment. Such other antioxidants may be selected from the group consisting of amino acids and derivatives thereof, imidazoles and derivatives thereof, urocanic acid, D,L-carnosine, D-carnosine, L-carnosine, anserine, alpha-carotene, beta-carotene, lycopene, chlorogenic acid and derivatives thereof, lipoic acid and derivatives thereof, dihydrolipoic acid, aurothioglucose, thiols and salts thereof, propylthiouracil, thioredoxin, glutathione, cysteine, cystine, cystamine, glycosyl, N-acetyl, methyl, ethyl, propyl, amyl, butyl and lauryl, palmitoyl, oleyl, gamma-linoleyl, cholesteryl and glyceryl esters of cystamine, dilauryl thiodipropionate, distearyl thiodipropionate, thiodipropionic acid and derivatives thereof, sulfoximine compounds, buthionine sulfoximines, homocysteine sulfoximine, buthionine sulfones, penta-, hexa-, and heptathionine sulfoximines, chelating agents, alpha-hydroxy fatty acids, palmitic acid, phytic acid, lactoferrin, alpha-hydroxy acids, citric acid, lactic acid, malic acid, humic acid, bile acid, bile extracts, bilirubin, biliverdin, EDTA, EGTA and derivatives thereof, unsaturated fatty acids and derivatives thereof, gamma-linolenic acid, linoleic acid, oleic acid, folic acid and derivatives thereof, ubiquinone, ubiquinol and derivatives thereof, vitamin C and derivatives thereof, ascorbyl palmitate, Mg ascorbyl phosphate, ascorbyl acetate, tocopherols and derivatives thereof, vitamin E acetate, vitamin A and derivatives thereof, vitamin A palmitate, coniferyl benzoate of benzoin, rutinic acid and derivatives thereof, alpha-glycosylrutin, ferulic acid, furfurylideneglucitol, carnosine, butylhydroxytoluene, butylhydroxyanisole, nordihydroguaiacic acid, nordihydroguaiaretic acid, trihydroxybutyrophenone, uric acid and derivatives thereof, mannose and derivatives thereof, zinc and derivatives thereof, ZnO, ZnSO₄, selenium and derivatives thereof, selenomethionine, stilbenes and derivatives thereof, stilbene oxide, trans-stilbene oxide, and combinations thereof.

[0042] In another aspect of this embodiment, the antioxidant flavonoid is selected from the group consisting of:

[0043] Preferably, the antioxidant flavonoid is administered as part of a pharmaceutical or a nutraceutical composition. Preferably, the antioxidant flavonoid derivative is administered as a unit dosage form.

[0044] Another embodiment of the present invention is a pharmaceutical composition that includes a carrier and one or more antioxidant flavonoids according to the present invention.

[0045] In another embodiment of the invention, there is provided a compound having a structure selected from:

or an enantiomer, optical isomer, diastereomer, N-oxide, crystalline form, hydrate, or pharmaceutically acceptable salt thereof. Another embodiment of this invention is a pharmaceutical composition that includes a carrier and one or more of the compounds of the present invention.

[0046] In a further embodiment of the present invention, there is provided a method for treating age-related macular degeneration (AMD). This method includes administering to a patient in need thereof an amount of a pharmaceutical composition according to the present invention, which amount sufficient to reduce oxidation of A2E in the patient's retina.

[0047] Another embodiment of the invention is a method for modulating photooxidation of A2E. This method comprises providing a photooxidation reducing amount of a compound of formula I, II, or III to, e.g., a cell or a mammal in need thereof. In the present invention, a "photooxidation reducing amount of a compound" is that amount of the compound which is sufficient to prevent or reduce or stabilize photooxidation of A2E in a cell or in a mammal, particularly a human suffering from, e.g., a macular dystrophy, such as AMD. Such amount may be determined by one skilled in the art, particularly with reference to Example 9 and FIG. 7.

[0048] In this embodiment, the compound is selected from the group consisting of:

[0049] In this embodiment, the providing step may include administering one or more of the compounds to a cell, particularly a cell of the eye, e.g., a retinal cell, in vivo or in vitro. In another aspect of this embodiment, the providing step may include administering one or more of the compounds of the present invention, in a pharmaceutical composition, to a patient.

[0050] Preferably, in this embodiment of the invention, "ameliorating" means a reduction of photooxidation of A2E.

[0051] As noted above, the compounds and compositions of the present invention may be used to treat, prevent, or ameliorate diseases and/or conditions associated with oxidation. Non-limiting examples of such diseases/conditions associated with oxidation include injury to the brain, such as a stroke; neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis; cancer; heart disease; prostasis; inflammation; allergies; respiratory diseases such as bronchitis and asthma; and environmental damage caused by, e.g., sun or UV irradiation. Preferably, the disease and/or condition associated with oxidation is a macular dystrophy, including for example, AMD, Stargardt, Vitelliform or Best (VMD), Sorsby's Fundus Dystrophy and Malattia Leventinese (Doyne Honeycomb or Dominant Radial Drusen). [0052] The compounds employed in the methods of the present invention may exist in prodrug form. As used herein, "prodrug" is intended to include any covalently bonded carriers which release the active parent drug, for example, as according to Formula I, II, or III, or other formulas or compounds employed in the methods of the present invention in vivo when such prodrug is administered to a mammalian subject. Because prodrugs are known to enhance numerous desirable qualities of pharmaceuticals (e.g., solubility, bioavailability, manufacturing, etc.), the compounds employed in the present methods may, if desired, be delivered in prodrug form. Thus, the present invention contemplates methods of delivering prodrugs. Prodrugs of the compounds employed in the present invention, for example Formula I, II, or III, may be prepared by modifying functional groups present in the compound in such a way that the modifications are cleaved, either in routine manipulation or in vivo, to the parent compound.

[0053] Accordingly, prodrugs include, for example, compounds described herein in which a hydroxy, amino, or carboxy group is bonded to any group that, when the prodrug is administered to a mammalian subject, cleaves to form a free hydroxyl, free amino, or carboxylic acid, respectively. Examples include, but are not limited to, acetate, formate and benzoate derivatives of alcohol and amine functional groups; and alkyl, carbocyclic, aryl, and alkylaryl esters such as methyl, ethyl, propyl, iso-propyl, butyl, isobutyl, sec-butyl, tert-butyl, cyclopropyl, phenyl, benzyl, or phenethyl esters.

[0054] Examples of prodrugs of the compounds of the present invention further include, but are not limited to, an amide derivative, thioamide derivative, carbamate derivative, thiocarbamate derivative, imide derivative, sulphonamide derivative, imine derivative, protonated imine derivative, isocyanate derivative, or isothiocyanate derivative of a compound of formula I, II, or III. [0055] As noted above, the compositions of the present invention may be administered in a unit dosage form, such as for example, as part of a vitamin supplement or a pharmaceutical formulation. Effective dosage forms, modes of administration, and dosage amounts may be determined empirically, and making such determinations is within the skill of the art. It is understood by those skilled in the art that the dosage amount will vary with the route of administration, the rate of excretion, the duration of the treatment, the identity of any other drugs being administered, the age, size, and species of animal, and like factors well known in the arts of medicine and veterinary medicine. In general, a suitable dose of a compound according to the invention will be that amount of the compound, which is the lowest dose effective to produce the desired effect. The effective dose of a compound maybe administered as two, three, four, five, six or more sub-doses, administered separately at appropriate intervals throughout the day.

[0056] By way of example only, in the case of eye drops, a compound or composition of the present invention may be administered to a patient, for example, from about 0.01 mg, about 0.1 mg, or about 1 mg, to about 25 mg, to about 50 mg, or to about 90 mg per single dose. Eye drops may be administered one or more times per day, as needed. In the case of injections, suitable doses may be, for example, about 0.0001 mg, about 0.001 mg, about 0.01 mg, or about 0.1 mg to about 10 mg, to about 25 mg, to about 50 mg, or to about 90 mg of a compound of formula I, II, or III or a derivative thereof, one to four times per week. In other embodiments, about 1.0 to about 30 mg of a compound or composition according to the present invention may be administered one to three times per week. [0057] Oral doses can typically range from about 1.0 to about 1000 mg, one to four times, or more, per day. An exemplary dosing range for oral administration is from about 10 to about 250 mg one to three times per day.

[0058] A compound of the present invention may be administered in any desired and effective manner: as a pharmaceutical composition for oral ingestion, or for parenteral or other administration in any appropriate manner such as intraperitoneal, subcutaneous, topical, intradermal, inhalation, intrapulmonary, rectal, vaginal, sublingual, intramuscular, intravenous, intraarterial, intrathecal, or intralymphatic. Further, a compound of the present invention may be administered in conjunction with other treatments. A compound or composition of the present invention maybe encapsulated or otherwise protected against gastric or other secretions, if desired.

[0059] While it is possible for a compound of the invention to be administered alone, it is preferable to administer the compound as a pharmaceutical formulation (composition) or a vitamin supplement. The pharmaceutically acceptable compositions of the invention comprise one or more compounds as an active ingredient in admixture with one or more pharmaceutically-acceptable carriers and, optionally, one or more other compounds, drugs, ingredients and/or materials. Regardless of the route of administration selected, the compounds of the present invention are formulated into pharmaceutically-acceptable dosage forms by conventional methods known to those of skill in the art. See, e.g., Remington's Pharmaceutical Sciences (Mack Publishing Co., Easton, Pa.). [0060] Pharmaceutically acceptable carriers are well known in the art (see, e.g., Remington's Pharmaceutical Sciences (Mack Publishing Co., Easton, Pa.) and The National Formulary (American Pharmaceutical Association, Washington, D. C)) and include sugars (e.g., lactose, sucrose, mannitol, and sorbitol), starches, cellulose preparations, calcium phosphates (e.g., dicalcium phosphate, tricalcium phosphate and calcium hydrogen phosphate), sodium citrate, water, aqueous solutions (e.g., saline, sodium chloride injection, Ringer's injection, dextrose injection, dextrose and sodium chloride injection, lactated Ringer's injection), alcohols (e.g., ethyl alcohol, propyl alcohol, and benzyl alcohol), polyols (e.g., glycerol, propylene glycol, and polyethylene glycol), organic esters (e.g., ethyl oleate and triglycerides), biodegradable polymers (e.g., polylactide-polyglycolide, poly(orthoesters), and poly(anhydrides)), elastomeric matrices, liposomes, microspheres, oils (e.g., corn, germ, olive, castor, sesame, cottonseed, and groundnut), cocoa butter, waxes (e.g., suppository waxes), paraffins, silicones, talc, silicylate, etc. Each pharmaceutically acceptable carrier used in a pharmaceutical composition of the invention must be "acceptable" in the sense of being compatible with the other ingredients of the formulation and not injurious to the subject. Carriers suitable for a selected dosage form and intended route of administration are well known in the art, and acceptable carriers for a chosen dosage form and method of administration can be determined using ordinary skill in the art. [0061] The pharmaceutical compositions or vitamin supplements of the invention may, optionally, contain additional ingredients and/or materials commonly used in such pharmaceutical compositions or vitamin supplements. These ingredients and materials are well known in the art and include (1 ) fillers or extenders, such as starches, lactose, sucrose, glucose, mannitol, and silicic acid; (2) binders, such as carboxymethylcellulose, alginates, gelatin, polyvinyl pyrrolidone, hydroxypropylmethyl cellulose, sucrose and acacia; (3) humectants, such as glycerol; (4) disintegrating agents, such as agar-agar, calcium carbonate, potato or tapioca starch, alginic acid, certain silicates, sodium starch glycolate, cross-linked sodium carboxymethyl cellulose and sodium carbonate; (5) solution retarding agents, such as paraffin; (6) absorption accelerators, such as quaternary ammonium compounds; (7) wetting agents, such as cetyl alcohol and glycerol monosterate; (8) absorbents, such as kaolin and bentonite clay; (9) lubricants, such as talc, calcium stearate, magnesium stearate, solid polyethylene glycols, and sodium lauryl sulfate; (10) suspending agents, such as ethoxylated isostearyl alcohols, polyoxyethylene sorbitol and sorbitan esters, microcrystalline cellulose, aluminum metahydroxide, bentonite, agar-agar and tragacanth; (11 ) buffering agents; (12) excipients, such as lactose, milk sugars, polyethylene glycols, animal and vegetable fats, oils, waxes, paraffins, cocoa butter, starches, tragacanth, cellulose derivatives, polyethylene glycol, silicones, bentonites, silicic acid, talc, salicylate, zinc oxide, aluminum hydroxide, calcium silicates, and polyamide powder; (13) inert diluents, such as water or other solvents; (14) preservatives; (15) surface-active agents; (16) dispersing agents; (17) control-release or absorption-delaying agents, such as hydroxypropylmethyl cellulose, other polymer matrices, biodegradable polymers, liposomes, microspheres, aluminum monosterate, gelatin, and waxes; (18) opacifying agents; (19) adjuvants; (20) wetting agents; (21 ) emulsifying and suspending agents; (22), solubilizing agents and emulsifiers, such as ethyl alcohol, isopropyl alcohol, ethyl carbonate, ethyl acetate, benzyl alcohol, benzyl benzoate, propylene glycol, 1 ,3-butylene glycol, oils (in particular, cottonseed, groundnut, corn, germ, olive, castor and sesame oils), glycerol, tetrahydrofuryl alcohol, polyethylene glycols and fatty acid esters of sorbitan; (23) propellants, such as chlorofluorohydrocarbons and volatile unsubstituted hydrocarbons, such as butane and propane; (24) antioxidants; (25) agents which render the formulation isotonic with the blood of the intended recipient, such as sugars and sodium chloride; (26) thickening agents; (27) coating materials, such as lecithin; and (28) sweetening, flavoring, coloring, perfuming and preservative agents. Each such ingredient or material must be "acceptable" in the sense of being compatible with the other ingredients of the formulation and not injurious to the subject. Ingredients and materials suitable for a selected dosage form and intended route of administration are well known in the art, and acceptable ingredients and materials for a chosen dosage form and method of administration may be determined using ordinary skill in the art.

[0062] Pharmaceutical compositions or vitamin supplements suitable for oral administration may be in the form of capsules, cachets, pills, tablets, powders, granules, a solution or a suspension in an aqueous or non-aqueous liquid, an oil-in- water or water-in-oil liquid emulsion, an elixir or syrup, a pastille, a bolus, an electuary or a paste. These formulations may be prepared by methods known in the art, e.g., by means of conventional pan-coating, mixing, granulation or lyophilization processes.

[0063] Solid dosage forms for oral administration (capsules, tablets, pills, dragees, powders, granules and the like) may be prepared by mixing the active ingredient(s) with one or more pharmaceutically-acceptable carriers and, optionally, one or more fillers, extenders, binders, humectants, disintegrating agents, solution retarding agents, absorption accelerators, wetting agents, absorbents, lubricants, and/or coloring agents. Solid compositions of a similar type maybe employed as fillers in soft and hard-filled gelatin capsules using a suitable excipient. A tablet may be made by compression or molding, optionally with one or more accessory ingredients. Compressed tablets may be prepared using a suitable binder, lubricant, inert diluent, preservative, disintegrant, surface-active or dispersing agent. Molded tablets may be made by molding in a suitable machine. The tablets, and other solid dosage forms, such as dragees, capsules, pills and granules, may optionally be scored or prepared with coatings and shells, such as enteric coatings and other coatings well known in the pharmaceutical-formulating art. They may also be formulated so as to provide slow or controlled release of the active ingredient therein. They may be sterilized by, for example, filtration through a bacteria-retaining filter. These compositions may also optionally contain opacifying agents and may be of a composition such that they release the active ingredient only, or preferentially, in a certain portion of the gastrointestinal tract, optionally, in a delayed manner. The active ingredient can also be in microencapsulated form.

[0064] Liquid dosage forms for oral administration include pharmaceutically- acceptable emulsions, microemulsions, solutions, suspensions, syrups and elixirs. The liquid dosage forms may contain suitable inert diluents commonly used in the art. Besides inert diluents, the oral compositions may also include adjuvants, such as wetting agents, emulsifying and suspending agents, sweetening, flavoring, coloring, perfuming and preservative agents. Suspensions may contain suspending agents. [0065] Pharmaceutical compositions for rectal or vaginal administration may be presented as a suppository, which maybe prepared by mixing one or more active ingredient(s) with one or more suitable nonirritating carriers which are solid at room temperature, but liquid at body temperature and, therefore, will melt in the rectum or vaginal cavity and release the active compound. Pharmaceutical compositions which are suitable for vaginal administration also include pessaries, tampons, creams, gels, pastes, foams or spray formulations containing such pharmaceutically-acceptable carriers as are known in the art to be appropriate.

[0066] Dosage forms for the topical or transdermal administration include powders, sprays, ointments, pastes, creams, lotions, gels, solutions, patches, drops and inhalants. In a further aspect the compounds and compositions of the present invention may be locally administered to the eye, such as, e.g., by eye drops, intraocular injection or periocular injection. Periocular injection typically involves injection of a compound or composition of the present invention into the conjunctiva or to the tennon (the fibrous tissue overlying the eye). Intraocular injection typically involves injection of a compound or composition of the present invention into the vitreous. In certain embodiments, administration of a compound or composition of the present invention is non-invasive, such as by eye drops or oral dosage form. [0067] The active compound may be mixed under sterile conditions with a suitable pharmaceutically-acceptable carrier. The ointments, pastes, creams and gels may contain excipients. Powders and sprays may contain excipients and propellants.

[0068] Pharmaceutical compositions suitable for parenteral administration comprise one or more compound(s) in combination with one or more pharmaceutically-acceptable sterile isotonic aqueous or non-aqueous solutions, dispersions, suspensions or emulsions, or sterile powders which may be reconstituted into sterile injectable solutions or dispersions just prior to use, which may contain suitable antioxidants, buffers, solutes which render the formulation isotonic with the blood of the intended recipient, or suspending or thickening agents. Proper fluidity can be maintained, for example, by the use of coating materials, by the maintenance of the required particle size in the case of dispersions, and by the use of surfactants. These compositions may also contain suitable adjuvants, such as wetting agents, emulsifying agents and dispersing agents. It may also be desirable to include isotonic agents. In addition, prolonged absorption of the injectable pharmaceutical form may be brought about by the inclusion of agents which delay absorption.

[0069] In some cases, in order to prolong the effect of a drug (e.g., pharmaceutical formulation or vitamin supplement), it is desirable to slow its absorption from subcutaneous or intramuscular injection. This may be accomplished by the use of a liquid suspension of crystalline or amorphous material having poor water solubility.

[0070] The rate of absorption of the drug then depends upon its rate of dissolution which, in turn, may depend upon crystal size and crystalline form. Alternatively, delayed absorption of a parenterally-administered drug may be accomplished by dissolving or suspending the drug in an oil vehicle. Injectable depot forms may be made by forming microencapsule matrices of the active ingredient in biodegradable polymers. Depending on the ratio of the active ingredient to polymer, and the nature of the particular polymer employed, the rate of active ingredient release can be controlled. Depot injectable formulations are also prepared by entrapping the drug in liposomes or microemulsions which are compatible with body tissue. The injectable materials can be sterilized for example, by filtration through a bacterial-retaining filter.

[0071] The formulations may be presented in unit-dose or multi-dose sealed containers, for example, ampules and vials, and may be stored in a lyophilized condition requiring only the addition of the sterile liquid carrier, for example water for injection, immediately prior to use. Extemporaneous injection solutions and suspensions may be prepared from sterile powders, granules and tablets of the type described above.

[0072] The following examples are provided to further illustrate the methods of the present invention. These examples are illustrative only and are not intended to limit the scope of the invention in any way. EXAMPLES

EXAMPLE 1 Synthesis Of Quercetin-3-Curcumin (Compound 8)

Preparation of diphenyl ketal aminoαuercetin (compound 3)

[0073] Quercetin (compound 1 ) was reacted with Ph₂CCI₂ to form diphenylketalquercetin (compound 2). Diphenylketalquercetin (210 mg, 0.45 mmol) was then dissolved in Dimethylformamide (DMF), treated with 135 mg (0.5 mmol) N- (benzyloxycarbonyl)-3-bromopropylmine and 62 mg (0.45 mmol) potassium carbonate. These components were stirred overnight under argon. Ethyl acetate was added to the reaction mixture, washed with 1 M HCI, and the ethyl acetate layer was concentrated in vacuo. The residue was purified by silica gel chromatography, with acetone and hexane at a ratio of 1 :3. The yield for this step was 60%.

Preparation of aminoquercetin (compound 4)

[0074] Diphenylketal aminoquercetin (compound 3) (51 mg, 0.08 mmol) was dissolved in 0.6 ml acetone, treated with 1 ml TFA, reacted for 1 hour under argon at 40° C, and submitted to silica gel chromatography, with ethyl acetate and hexane at a ratio of 1 :1. The yield for this step was 95%.

Preparation of 4'-(3-carboxy - propoxy) curcumin (compound 6) [0075] To curcumin I (220 mg, 0.6 mmol) in 2 ml DMF was added 100 mg

(0.72 mmol) potassium carbonate, and ethyl 4-bromobutyrate (0.1 mmol). These components were stirred for 12 hours under argon. After addition of ethyl acetate, the mixture was washed with 1 M HCI, and the ethyl acetate layer was evaporated in vacuo. The reaction mixture was then dissolved in dioxane, and the ethyl ester of compound 6 was hydrolyzed by treating for 1 hour at room temperature with 5% NaOH. Ethyl acetate was added to the reaction mixture, followed by washing with 1 M HCI. The ethyl acetate was evaporated in vacuo, and the residue was chromatographed through silica gel, with ethyl acetate and hexane at a ratio of 1 :1.

Preparation of activated ester (Compound 7)

[0076] Compound 6, 4'-(3-carboxy-propoxy) curcumin, (130 mg, 0.29 mmol) in pyridine (11) was treated with acetic anhydride (12), reacted at room temperature for 1 hour, and concentrated to dryness. The residue in DMF was treated with N- hydroxysuccinimide hydrochloride (WSC) 118 mg (0.58 mmol), stirred overnight, extracted with ethyl acetate and 1 M HCI and purified by silica gel chromatography, with ethyl acetate and hexane at a ratio of 1 :1. The yield for these two steps was 65%.

Preparation of antioxidant flavonoid (Compound 8)

[0077] Aminoquercetin (compound 4) (36 mgm 0.07 mmol) in 3 ml MeOH was stirred for 1 hour at room temperature, with 10% PdC. The reaction mixture was filtered and the filtrate evaporated to dryness. The residue in 3.5 ml DMF was treated with 42.3 mg (0.07 mmol) curcumin activated ester (compound 7), stirred for 1 day at room temperature, purified through silica gel chromatography with acetone and chloroform at a ratio of anywhere from 0:1 to 2:3, to give compound 8a. The yield for these 2 steps was 35%. [0078] The acetate (compound 8a), 5.3 mg, in dioxane is hydrolyzed with 5% sodium bicarbonate and extracted with ethyl acetate and 1 M HCI to form compound 8. The organic layer is evaporated to dryness. The residue is purified by reverse phase High Performance Liquid Chromatography (HPLC).

Example 2 Synthesis Of Quercetin-3-Caffeic Acid (Compound 15)

Preparation of diphenyl ketal aminoquercetin (compound 3)

[0079] Quercetin (compound 1 ) is reacted with Ph₂CCI₂ to form diphenylketalquercetin (compound 2). Diphenylketalquercetin (210 mg, 0.45 mmol) is then dissolved in dimethylformamide (DMF) and treated with 135 mg (0.5 mmol) N-(benzyloxycarbonyl)-3-bromopropylmine and 62 mg (0.45 mmol) potassium carbonate. The reaction mixture is stirred overnight under argon. Ethyl acetate is added to the reaction mixture, washed with 1 M HCI, and the ethyl acetate layer is concentrated in vacuo, and the residue is purified by silica gel chromatography, with acetone and hexane at a ratio of 1 :3. The yield for this step is about 60%.

Preparation of aminoquercetin (compound 4)

[0080] Diphenylketal aminoquercetin (compound 3) (51 mg, 0.08 mmol) is dissolved in 0.6 ml acetone, treated with 1 ml TFA, reacted for 1 hour under argon at 40° C, and submitted to silica gel chromatography, with ethyl acetate and hexane at a ratio of 1 :1. The yield for this step is about 95%.

Preparation of caffeic acid activated ester (compound 14) [0081] Caffeic acid (compound 9) in pyridine (compound 11) is treated with acetic anhydride (compound 12). The resulting compound (compound 13) is then treated with N-hydroxysuccinimide hydrochloride (WSC) to yield compound 14.

Preparation of Quercetin-3-Caffeic Acid (compound 15)

[0082] Aminoquercetin (compound 4) is stirred with 10% PdC. The reaction mixture is filtered and the filtrate evaporated to dryness. The residue in DMF is treated with caffeic activated ester (compound 14) purified through silica gel chromatography to yield compound 15Ac. Compound 15Ac in dioxane is hydrolyzed with 5% sodium bicarbonate and extracted with ethyl acetate and 1 M HCI to form compound 15. The organic layer is evaporated to dryness. The residue is purified by reverse phase High Performance Liquid Chromatography (HPLC).

Example 3 Synthesis Of Quercetin-3,7-di-Caffeic Acid (Compound 16)

Preparation of an aminoquercetin analog (compound 4a)

[0083] Quercetin (compound 1) is reacted with Ph₂CCI₂ to form diphenylketalquercetin (compound 2). Diphenylketalquercetin is then dissolved in dimethylformamide (DMF), treated with 2 equivalents of N-(benzyloxycarbonyl)-3- bromopropylmine. The resulting compound (compound 3a) is then dissolved in acetone and treated with TFA to yield compound 4a.

Preparation of Quercetin-3.7-di-Caffeic Acid (Compound 16) [0084] Caffeic acid activated ester (compound 14) is prepared as described in

Example 2.

[0085] Aminoquercetin analog (compound 4a) is stirred with 10% PdC. The reaction mixture is filtered and the filtrate evaporated to dryness. The residue in DMF is treated with 2 equivalents of caffeic activated ester (compound 14) purified through silica gel chromatography to yield compound 16Ac. Compound 16Ac in dioxane is hydrolyzed with 5% sodium bicarbonate and extracted with ethyl acetate and 1 M HCI to form compound 16. The organic layer is evaporated to dryness. The residue is purified by reverse phase High Performance Liquid Chromatography (HPLC).

Example 4 Synthesis Of Quercetin-7-Caffeic Acid (Compound 17)

Preparation of an aminoquercetin analog (compound 4b)

[0086] Quercetin (compound 1 ) is reacted with Ph₂CCI₂ to form diphenylketalquercetin (compound 2). Diphenylketalquercetin is then treated with benzyl bromide and potassium carbonate in dimethylformamide (DMF). Thereafter, the reaction mixture is treated with about 1 equivalent of N-(benzyloxycarbonyl)-3- bromopropylmine and potassium carbonate in DMF. The resulting compound (3b) is then dissolved in acetone and treated with TFA to yield compound 4b.

Preparation of caffeic acid activated ester (compound 14)

[0087] Caffeic acid (compound 9) in pyridine (11) is treated with acetic anhydride (12). The resulting compound (13) is then treated with N- hydroxysuccinimide hydrochloride (WSC) to yield compound 14. Preparation of Quercetin-7-Caffeic Acid (Compound 17)

[0088] Aminoquercetin (compound 4b) is stirred with 10% PdC. The reaction mixture is filtered and the filtrate evaporated to dryness. The residue in DMF is treated with caffeic activated ester (compound 14) purified through silica gel chromatography to yield compound 17Ac. Compound 17Ac in dioxane is hydrolyzed with 5% sodium bicarbonate and extracted with ethyl acetate and 1 M HCI to form compound 17. The organic layer is evaporated to dryness. The residue is purified by reverse phase High Performance Liquid Chromatography (HPLC).

Example 5 Synthesis Of Quercetin-Glucoside-Caffeic Acid (Compound 22)

Preparation of qlucoside caffeic acid activated ester (compound 21 )

[0089] A glucoside (compound 20) is reacted under conditions sufficient to form a glucoside caffeic acid activated ester (compound 21 ).

Preparation of quercetin-αlucoside-caffeic acid (compound 22) [0090] Quercetin (compound 1 ) is reacted with Ph₂CCI₂ to form diphenylketalquercetin (compound 2). The resulting compound is treated with glucoside caffeic acid activated ester (compound 21 ) and potassium carbonate in DMF. Thereafter, the reaction mixture is treated with TFA to yield a quercetin- glucoside-caffeic acid (compound 22). Example 6 Synthesis Of Quercetin-Xanthophyll (Compound 19)

Preparation of diphenyl ketal aminoquercetin (compound 3)

[0091] Quercetin (compound 1 ) is reacted with Ph₂CCI₂ to form diphenylketalquercetin (compound 2). Diphenylketalquercetin (210 mg, 0.45 mmol) is then dissolved in Dimethylformamide (DMF), treated with 135 mg (0.5 mmol) N- (benzyloxycarbonyl)-3-bromopropylmine and 62 mg (0.45 mmol) potassium carbonate. These components are stirred overnight under argon. Ethyl acetate is added to the reaction mixture, washed with 1 M HCI, and the ethyl acetate layer is concentrated in vacuo. The residue is purified by silica gel chromatography, with acetone and hexane at a ratio of 1 :3. The yield for this step is about 60%.

Preparation of aminoquercetin (compound 4)

[0092] Diphenylketal aminoquercetin (compound 3) (51 mg, 0.08 mmol) is dissolved in 0.6 ml acetone, treated with 1 ml TFA, reacted for 1 hour under argon at 40° C₁ and submitted to silica gel chromatography, with ethyl acetate and hexane at a ratio of 1 :1. The yield for this step is about 95%.

Preparation of Xanthophyll activated ester (compound 18)

[0093] A xanthophyll (compound 10) in pyridine (11) is first treated with ethyl

4-bromobutyrate and sodium hydride in DMF. 1 M sodium hydroxide and dioxane is added and is followed by treatment with acetic anhydride (12), and finally with hydroxysuccinimide hydrochloride (WSC) to yield compound 18. Preparation of Quercetin-Xanthophyll (Compound 19)

[0094] Aminoquercetin (compound 4) is stirred with 10% PdC. The reaction mixture is filtered and the filtrate evaporated to dryness. The residue in DMF is treated with the xanthophyll activated ester (compound 18) and purified through silica gel chromatography to yield compound 19Ac. Compound 19Ac in dioxane is hydrolyzed with 5% sodium bicarbonate and extracted with ethyl acetate and 1 M HCI to form compound 19. The organic layer is evaporated to dryness. The residue is purified by reverse phase High Performance Liquid Chromatography (HPLC).

Example 7 Synthesis Of A Quercetin-Caffeic Acid Conjugate (Compound 25)

13 14

Yield 76% (2 steps)

(3 steps)

Synthesis of Compound 25

[0095] 3',4',7-tribenzylquercetin 23 (198mg (0.35mmol)) was dissolved in

DMF, treated with 114mg (0.45mmol) 4-(Boc-amino)butyl bromide and 64mg (0.46mmol) potassium carbonate and stirred for 3 hours under argon. EtOAc was added to the reaction mixture, washed with 1 M HCI, and the EtOAc layer was concentrated in vacuo, and the residue was purified by silica gel chromatography, 50% EtOAc in hexane.

[0096] A solution of 24 in MeOH-CH₂CI₂ (1 :1 , v/v) was hydrogenated over

10% Pd-C under an atmospheric pressure of hydrogen for over night. After removal of the catalyst by filtration, the filtrate was concentrated in vacuo, and the residue (25) was purified by silica gel chromatography, 5% MeOH in CH₂CI₂, yield 74% (2 steps). Compound 25 was analyzed as set forth below:

[0097] NMR δ_H (CD₃OD, 600MHz); 1.43(9H, s, t-Bu), 1.58(2H, qu, J=6.87, H-

3"), 1.73(2H, qu, J=6.19 & 6.87, H-2"), 3.05(2H, t, J=6.87, H-4"), 3.91(2H, t, J=6.19, H-1"), 6.18(1 H, d, J=2.06, H-6 or 8), 6.36(1 H, d, J=2.06, H-6 or 8), 6.89(1 H, d, J=8.76, H-3'), 7.49(1 H, dd, J=2.06 & 8.76, H-2¹), 7.57(1 H, d, J=2.06, H-6'). NMR δ_c (CD₃OD, 150MHz); 26.04(C-2"), 26.95(C-3"), 27.49(3Me), 39.70(C-4"), 72.19(C-1"), 78.57(C-8"), 93.36(C-6), 98.38(C-8), 104.61(07), 114.97(C-3'), 115.35(C-6'), 121.18(C-2'), 121.79(01 '), 137.27(C-3), 144.99(05'), 148.47(04'), 156.97(03), 157.08(05), 157.25(06"), 161.78(C-8b), 164.45(O4a), 178.77(04).

Synthesis of compound 14

[0098] 3,4-diacethylcaffeic acid 13 (97mg (0.37mmol)) was synthesized, as shown, from compound 9. Compound 13 in DMF was then treated with N-hydroxy- succinimide hydrochloride 86mg (0.74mmol) and N-Ethyl-N'-(3-dimethyl- aminopropyl)-carbodiimide hydrochloride (WSC) 146mg (0.76mmol), stirred overnight, extracted with EtOAc/1 M HCI and purified by silica gel chromatography, 50% EtOAc in hexane. Yield for 2 steps 74 %. Synthesis of flavonoid 26

[0099] Compound 25. (55mg, 0.12mmol) was dissolved in 1.5 ml MeOH, treated with 25%HBr/AcOH 0.3 ml, and reacted for 2 hours under argon at 40⁰C. The reaction mixture was evaporated to dryness. The residue in 1.5 ml DMF was treated with 75μl triethylamine and 48.3mg(0.13mmol) compound 14 and stirred for 3 hours at room temperature. EtOAc was added to the reaction mixture, washed with 1 M HCI, and the EtOAc layer was concentrated in vacuo. The reaction mixture was then dissolved in 10ml NH₄OAc solution (62mg/ml MeOH:H₂O=4:1 ), stirred for 4 hours at room temperature, extracted with EtOAc/1 M HCI, and the organic layer was evaporated to dryness. The residue (26) was purified by reverse phase HPLC. Yield for 3 steps 67 %. Compound 26 was analyzed as set forth below: [0100] ESI-MS, m/z 558 [M+Na]⁺. NMR δ_H (CD₃OD, 600MHz); 1.67(2H, qu,

J=6.87, H-2"), 1.80(2H, qu, J=6.19, H-3"), 3.31(2H, m, H-1"), 3.93(2H, t, J=6.19, H- 4"), 6.18(1 H, d, J=2.06, H-8), 6.36(1 H, brs, H-6), 6.37(1 H, d, J=15.1 , H-7"), 6.76(1 H, d, J=8.25, H-10"), 6.90(2H, m, H-2" & 11"), 7.01(1 H, brd, J=2.06, H-14"), 7.38(1 H, d, J=15.1 , H-8"), 7.49(1 H, dd, J=2.06 & 8.25, H-3'), 7.59(1 H, d, =2.06, H-6'). NMR δ_c (CD₃OD, 150MHz); 25.70(C-2"), 27.11(C-3"), 38.92(C-4"), 72.11(C-1"), 93.41 (C-6), 98.47(C-8), 104.60(C-14"), 113.79(C-2'), 115.00(C-10"), 115.13(C-6'), 117.11(C-7"), 120.79(C-11"), 121.16(C-3'), 127.00(C-9"), 137.27(C-3), 140.86(C-8"), 144.99(C-2), 145.34(C-12"), 147.37(C-13"), 148.51 (C-4), 157.00(C-5 or 5'), 157.08(C-5 or 5'), 161.75(C-8b), 164.55(C-4a), 168.03(C-6"), 178.74(C-4). Example 8 Synthesis Of A Quercetin-Curcumin I Conjugate (Compound 27)

S: Curcumin I

Synthesis of Compound 6

[0101] To curcumin I (220 mg, 0.6 mmol) in 4 ml DMF was added 100 mg

(0.72 mmol) potassium carbonate and ethyl 4-bromobutyτate 0.1 ml (0.72 mmol). The mixture was stirred for 12 hours under argon. After addition of ethyl acetate, the mixture was washed with 1 M HCI and the ethyl acetate layer was evaporated in vacuo. The reaction mixture was then dissolved in dioxane, and the ethyl ester was hydrolyzed by treating for 1 hour at room temperature with 5 % NaOH. Ethyl acetate was added to the reaction mixture, washed with 1 M HCI, the ethyl acetate was evaporated in vacuo, and the residue was chromatographed through silica gel with ethyl acetate/hexane (1/1 ). This compound in pyridine (11) was a treated with acetic anhydride (12), reacted at room temperature for 1 hour, and concentrated to dryness. The residue (6) was purified by silica gel chromatography, 2% MeOH in CH₂CI₂. Yield for 3 steps 44%. Compound 6 was analyzed as set forth below: [0102] NMR δ_H (de-DMSO, 600MHz);1.99 (2H, qu, J=6.87, H-3'), 2.42 (2H₁ t,

J=6.87, H-2'), 4.04 (2H₁ t, J=6.87, H-4'), 6.10 (1 H, br.s, H-10), 6.74 (1 H, s, J=15.1 , H-8 or 2), 6.79 (1 H, d, J=16.5, H-8 or 12), 6.86 (1 H, d, J=8.25, H-5), 6.99 (1 H, d, J=8.25, H-18), 7.16 (1H, brd, J=7.56, H-6), 7.22 (1H, br.d, J=7.56, H-19), 7.29 (1 H, br.s, H-2 or 15), 7.31 (1 H, br.s, H-2 or 15), 7.56 (2H, d, J=15.8, H-7 & H-13). NMR δ_c (d₆-DMSO, 150MHz);24.64 (C-3¹), 30.54 (C-2¹), 56.13 (OMe x 2), 67.82 (C-4¹), 101.66 (C-10), 111.01 (C-2 or 15), 111.56 (C-2 or 15), 113.21 (C-18), 116.17 (C-5), 121.53 (C-12), 122.45 (C-8), 123.28 (C-6 or 19), 123.61 (C-6 or 19), 126.82 (C-14), 128.14 (C-1 ), 140.62 (C-7), 141.39 (C-13), 148.47 (C-16), 149.63 (C-3), 149.76 (C- 17), 150.55 (C-4), 174.86 (C-1'), 183.17 (C-9 or 11), 184.13 (C-9 or 11).

Synthesis of activated ester 7

[0103] Compound 6 (81 mg, 0.17 mmol) in DMF was treated with N-hydroxy- succinimide hydrochloride 39mg (0.34mmol) and N-Ethyl-N'-(3-dimethyl- aminopropyl)-carbodiimide hydrochloride (WSC) 109mg (0.5 mmol), stirred overnight, and extracted with EtOAc/1 M HCI. The ethyl acetate was evaporated in vacuo, and purified by silica gel chromatography with 50% EtOAc in hexane to yield compound 7. Yield 73 %.

Synthesis of Compound 27

[0104] Compound 25 (40mg, 0.086mmol) was dissolved in 1 ml MeOH, treated with 25%HBr/AcOH 0.2 ml, reacted for 1 hour under argon at 40⁰C. The reaction mixture was evaporated to dryness. The residue in 1.5 ml DMF was treated with 75μl triethylamine and compound 7 56mg(0.094mmol), and stirred for 3 hours at room temperature. EtOAc was added to the reaction mixture, washed with 1 M HCI, and the EtOAc layer was concentrated in vacuo. The reaction mixture was then dissolved in 2ml NH₄OAc solution (62mg/ml MeOH:H₂O=4:1 ), stirred for 4 hours at room temperature, extracted with EtOAc/1 M HCI and the organic layer was evaporated to dryness. The residue (27) was purified by reverse phase HPLC. Yield for 3 steps 73 %. Compound 27 was analyzed as set forth below: [0105] ESI-MS, m/z 832 [M+Naf. NMR δ_H (deAcetone, 600MHz);1.69 (2H₁ qu, J=6.87, H-2"), 1.78(2H, qu, J=6.87, H-3"), 2.13 (2H, br.qu, J=6.19, H-8"), 2.47 (2H₁ br.t, J-6.87, H-3"), 2.13 (2H, br.qu, J=6.19, H-8"), 2.47 (2H, br.t, J=6.87, H-7"), 3.32 (2H₁ br.t, J=6.87, H-42), 3.85 (3H, s, OMe), 3.91 (3H, s, OMe), 4.02 (2H, br.t, J=6.19, H-1"), 4.06 (2H₁ br.t, J=6.19, H-9"), 5.87 (1 H, br.s, H-IOc), 6.26 (1 H₁ br.s, H- 6 or 8), 6.48 (1 H, br.s, H-6 or 8), 6.64 (1 H, d, J=16.5, H-8c), 6.68 (1 H, d, J-16.5, H- 12c), 6.89 (1 H, d, J=8.94, H-18c), 6.91 (1 H, d, J=8.94, H-5c), 7.00 (1 H, d, J-6.87, H- 3"), 7.11 (1 H, d, J=7.56, H-6c), 7.16 (1 H, d, J=8.25, H-19c), 7.23 (1 H, br.s, H-2c), 7.30 (1 H, br.s, H-15c), 7.51 (1 H, d, J-6.87, H-2'), 7.54 (1 H, d, J=15.81 , H-7c), 7.58 (1 H, d, J=15.81 , H-13c), 7.80 (1 H, br.s, H-6¹). NMR δ_c (deAcetone, 150MHz); 25.32(C-8"), 26.00 (C-2"), 27.09 (C-3"), 32.39 (C-7"), 38.74 (C-4"), 55.46 (OMe), 55.54 (OMe), 68.04 (C-9"), 71.77 (C-1"), 93.74 (C-6 or 8), 98.60 (C-6 or 8), 101.10 (C-IOc), 104.95 (C-7), 110.76 (C-15c), 110.90 (C-2c), 112.98 (C-5c), 115.40 (C-3' and 18c), 115.84 (C-6¹), 121.07 (C-2¹), 121.52 (C-12c), 122.13 (C-8c), 122.53 (C- 6c), 123.03 (C-19c), 127.35 (C-14c), 128.22 (C-1c), 137.50 (C-3), 140.16 (C-7c), 140.63 (C-13c), 144.94 (C-2), 147.92 (C-16c), 148.41 (C-T), 149.80 (C-3c), 150.76 (C-4c), 156.12 (C-4¹), 157.00 (C-5 and 5'), 162.03 (C-8b), 164.16 (C-4a), 176.17 (C- 6"), 178.64 (C-4), 182.80 (C-11c), 183.45 (C-9c). Example 9 Quercetin Conjugates Reduce A2E Photooxidation

[0106] To photooxidize samples of A2E, 200 μM A2E (synthesized, e.g., using the procedure of (18)) in 0.1 mL dimethyl sulfoxide (DMSO) was added to 0.2 ml. of D-PBS with and without compounds of interest at 50, 100, and 200 μM concentrations. Each mixture was subsequently illuminated at 430 nm (for 7 min). A2E was quantitated by reverse-phase HPLC (C18 column, 150X 4.6 mm; Waters). The area under the peak was normalized to an external standard of A2E. [0107] As shown in FIG. 7, photooxidation of A2E is reflected in the reduced content of A2E in a sample after 430 nm illumination. The loss of A2E was diminished in the presence of antioxidants as shown.

CITED DOCUMENTS

[0108] The following documents, which have been cited above, are incorporated by reference as if recited in full herein:

1. Rattner, A.; Nathans, J. Macular degeneration: recent advances and therapeutic opportunities. Nat. Rev. Neurosci. 2006, 7, 860-872.

2. Jarc-Vidmar, M.; Kraut, A.; Hawlina, M. Fundus autofluorescence imaging in Best's vitelliform dystrophy. Klinische Monatsblatter Fur Augenheilkunde 2003, 220, 861-867.

3. Capon, M.; Marshall, J.; Krafft, J.; Alexander, R.; Hiscott, P.; Bird, A. Sorsby's fundus dystrophy: a light and electron microscopic study. Ophthalmology 1989, 95, 1969-1977. 4. Chong, N.; Alexander, R.; Gin, T.; Bird, A.; Luthert, P. TIMP-3 collagen, and elastin immunohistochemistry and histopathology of Sorsby's fundus dystrophy Invest Ophthamol Vis Sci 2000, 41, 898-902.

5. Alikmets, R.; Singh, N.; Sun, H.; Shroyer, N. F.; Hutchinson, A.; Chidambaram, A.; Gerrard, B.; Baird, L.; Stauffer, D.; Peiffer, A.; Rattner, A.; Smallwood, P.; Li, Y.; Anderson, K.L.; Lewis, R.A.; Nathans, J.; Leppert, M.; Dean, M.; R., L.J. A Photoreceptor cell-specific ATP-binding transporter gene (ABCR) is mutated in recessive Stargardt macular dystrophy. Nat. Genet. 1997, 15, 236- 246.

6. Sparrow, J. S.; Nakanishi, K.; Parish, CA. The lipofuscin fluorophore A2E mediates blue light-induced damage to retinal pigmented epithelial cells. Invest. Ophthamol. Vis. Sci. 2000, 41, 1981-1989.

7. Suter, M.; Reme, CE. ; Christian Grimm; Wenzel, A.; Jaattela, M.; Esser, P.; Kociok, N.; Leist, M.; Richter, C. Age-related Macular Degeneration: The lipofuscin component n-retinyl-n-retinylidene ethanolamine detaches proapoptotic proteins from mitochondria and induces apoptosis in mammalian retinal pigment epithelial cells. J. Bio. Chem. 2000, 275, 39625-39630.

8. Ham, W. T.; J. J. Ruffolo; H. A. Mueller; A. M. Clarke and M. E. Moon Histologic analysis of photochemical lesions produced in rhesus retina by short-wavelength light. Invest. Ophthalmol. Vis. Sci. 1978, 17, 1029-1035.

9. Ham, W. T.; H. A. Mueller; J. J. Ruffolo; J. E. Millen; S. F. Cleary; R. K. Guerry; and Guerry, D. Basic mechanisms underlying the production of photochemical lesions in the mammalian retina. Curr. Eye Res. 1984, 3, 165- 174. 10. Sparrow, J. R.; Zhou, J.; Ben-Shabat, S.; Vollmer, H.; Itagaki, Y.; Nakanishi, K. Invest. Ophthalmol. Visual Sci. 2002, 43:, 1222-1227.

11. Ben-Shabat, S.; Itagaki, Y.; Jockusch, S.; Sparrow, J. R.; Turro, N. J.; Nakanishi, K. Angew. Chem. Int. Ed. 2002, 41:, 814-817.

12. Sparrow, J. R.; K. Nakanishi; Parish C. A. The lipofuscin fluorophore A2E mediates blue light-induced damage to retinal pigmented epithelial cells. Invest. Ophthalmol. Vis. Sci. 2000, 41, 1981-1989.

13. Suter, M.; C. Reme; C. Grimm; A. Wenzel; M. Jaattela; P. Esser; N. Kociok; M. Leist; Richter C. Age-related macular degeneration. The lipofuscin component N-retinyl-N-retinylidene ethanolamine detaches proapoptotic proteins from mitochondria and induces apoptosis in mammalian retinal pigment epithelial cells. J. Biol. Chem. 2000, 275, 39625-39630.

14. Ragauskaite, L.; R. C. Heckathorn; Gaillard E. R. Environmental effects on the photochemistry of A2E, a component of human retinal lipofuscin. Photochem. Photobiol. 2001, 74, 483-488.

15. Reszka, K.; Eldred, G. E.; Wang, R. H.; Chignell, C; Dillon, J. The photochemistry of human retinal lipofuscin as studied by EPR. Photochem. Photobiol. 1995, 62, 1005-1008.

16. Sparrow, J. R.; Vollmer-Snarr, H. R.; Zhou, J.; Jang, Y. P.; Jockush, S.; Itahaki, Y.; Nakanishi, K. A2E-epoxides damage DNA in retinal pigment epithelial cells. J. Biol. Chem. 2003, 278, 18207-18213.

17. Jang, Y.P.; Zhou, J.; Nakanishi, K.; Sparrow, J. R. Anthocyanins protect against A2E photooxidation and membrane permeabilization in retinal pigment epithelial cells. Photochem Photobiol. 2005, 81, 529-36. 18. Parish, C.A.; Hashimoto, M.; Nakanishi, K.; Dillon, J., and Sparrow, J. Isolation and one-step preparation of A2E and iso-A2E, fluorophores from human retinal pigment epithelium. Proc. Natl. Acad. Sci. USA. 1998, 95, 14609-14613.

[0109] The scope of the present invention is not limited by the description, examples, and suggested uses herein and modifications can be made without departing from the spirit of the invention. Thus, it is intended that the present invention cover modifications and variations of this invention provided that they come within the scope of the appended claims and their equivalents.

Claims

What is claimed is:

1. A method for making an antioxidant flavonoid comprising reacting quercetin or a quercetin glycoside under conditions sufficient to link an antioxidant to the quercetin or quercetin glycoside.

2. The method according to claim 1 , wherein the reacting step comprises:

(a) contacting quercetin with

under conditions sufficient to form compound 2:

(2)

(b) contacting compound 2 with N-(benzyloxycarbonyl)-3- bromopropylamine under conditions sufficient to form compound 3:

(c) contacting compound 3 with acetone and TFA under conditions sufficient to form compound 4:

(e) contacting compound 6 with acetic anhydride followed by N- hydroxysuccinimide hydrochloride under conditions sufficient to form compound 7:

(f) contacting compound 4 with compound 7 under conditions sufficient to form compound 8a:

(g) hydrolyzing compound 8a under conditions sufficient to form compound

8:

3. The method according to claim 2, wherein compound 8 is purified.

4. The method according to claim 1 , wherein the reacting step comprises:

(a) contacting 3', 4', 7 -Tribenzylquercetin with 4-(Boc-amino)butyl bromide and potassium carbonate under conditions sufficient to form compound 24:

¹⁴ ; and

(e) contacting compound 25 sequentially with HBr/AcOH followed by triethylamine and compound 14 followed by a solution of NH₄OAc under conditions sufficient to form compound 26:

5. The method according to claim 4, wherein compound 26 is purified.

6. The method according to claim 1 , wherein the reacting step comprises:

(a) contacting curcumin I sequentially with potassium carbonate and ethyl 4-bromobutyrate followed by NaOH and dioxane, followed by Ac₂O and pyrimidine under conditions sufficient to form compound 6:

27

7. The method according to claim 6, wherein compound 27 is purified.

8. A method for making an antioxidant flavonoid comprising: (a) reacting a compound of formula (I):

(I)

9. The method according to claim 8, wherein the antioxidant is selected from the group consisting of curcumin I, caffeic acid, carotenoids, and derivatives thereof.

10. The method according to claim 9, wherein the antioxidant is curcumin I.

11. The method according to claim 9, wherein the antioxidant is caffeic acid.

12. The method according to claim 9, wherein the antioxidant is a carotenoid.

13. The method according to claim 12, wherein the carotenoid is a xanthophyll or a carotene.

14. The method according to claim 8, wherein the antioxidant is selected from the group consisting of amino acids and derivatives thereof, imidazoles and derivatives thereof, urocanic acid, D,L-camosine, D-carnosine, L-carnosine, anserine, alpha- carotene, beta-carotene, lycopene, chlorogenic acid and derivatives thereof, lipoic acid and derivatives thereof, dihydrolipoic acid, aurothioglucose, thiols and salts thereof, propylthiouracil, thioredoxin, glutathione, cysteine, cystine, cystamine, glycosyl, N-acetyl, methyl, ethyl, propyl, amyl, butyl and lauryl, palmitoyl, oleyl, gamma-linoleyl, cholesteryl and glyceryl esters of cystamine, dilauryl thiodipropionate, distearyl thiodipropionate, thiodipropionic acid and derivatives thereof, sulfoximine compounds, buthionine sulfoximines, homocysteine sulfoximine, buthionine sulfones, penta-, hexa-, and heptathionine sulfoximines, chelating agents, alpha-hydroxy fatty acids, palmitic acid, phytic acid, lactoferrin, alpha-hydroxy acids, citric acid, lactic acid, malic acid, humic acid, bile acid, bile extracts, bilirubin, biliverdin, EDTA, EGTA and derivatives thereof, unsaturated fatty acids and derivatives thereof, gamma-linolenic acid, linoleic acid, oleic acid, folic acid and derivatives thereof, ubiquinone, ubiquinol and derivatives thereof, vitamin C and derivatives thereof, ascorbyl palmitate, Mg ascorbyl phosphate, ascorbyl acetate, tocopherols and derivatives thereof, vitamin E acetate, vitamin A and derivatives thereof, vitamin A palmitate, coniferyl benzoate of benzoin, rutinic acid and derivatives thereof, alpha-glycosylrutin, ferulic acid, furfurylideneglucitol, carnosine, butylhydroxytoluene, butylhydroxyanisole, nordihydroguaiacic acid, nordihydroguaiaretic acid, trihydroxybutyrophenone, uric acid and derivatives thereof, mannose and derivatives thereof, zinc and derivatives thereof, ZnO, ZnSO-J, selenium and derivatives thereof, selenomethionine, stilbenes and derivatives thereof, stilbene oxide, trans-stilbene oxide, and combinations thereof.

15. The method according to claim 8 further comprising purifying the antioxidant flavonoid.

16. The method according to claim 8, wherein the glycone portion of the glycoside is selected from the group consisting of aldopentose, aldohexose, aldotetrose, ketopentose and ketohexose.

17. The method according to claim 8, wherein the glycone portion of the glycoside is selected from the group consisting of ribose, arabinose, xylose, lyose; allose, altrose, glucose, mannose, gulose, idose, galactose, talose, fucose, rhamnose, ribulose, xylulose, erythrose, threose, psicose, fructose, sorbose, and tagatose.

18. The method according to claim 9, wherein the antioxidant flavonoid is:

19. A method for treating age-related macular degeneration (AMD) comprising administering to a patient in need thereof an amount of an antioxidant flavonoid made according to the method of any one of claims 1 or 4.

20. An antioxidant flavonoid of the formula Il or

(H) (Hi)

wherein

R2, R3, R4, R5, R₆, and R₇ are independently selected from H and an antioxidant, with the proviso that R₂, R₃, R4, R5, Re, and R₇ are not all H.

21. The antioxidant flavonoid according to claim 20, wherein the antioxidant is selected from the group consisting of curcumin I, caffeic acid, carotenoids, and derivatives thereof.

22. The antioxidant flavonoid according to claim 21 , wherein the antioxidant is curcumin I.

23. The antioxidant flavonoid according to claim 21 , wherein the antioxidant is caffeic acid.

24. The antioxidant flavonoid according to claim 21 , wherein the antioxidant is a carotenoid.

25. The antioxidant flavonoid according to claim 24, wherein the carotenoid is a xanthophyll or a carotene.

26. The method according to claim 20, wherein the antioxidant is selected from the group consisting of amino acids and derivatives thereof, imidazoles and derivatives thereof, urocanic acid, D,L-carnosine, D-carnosine, L-carnosine, anserine, alpha-carotene, beta-carotene, lycopene, chlorogenic acid and derivatives thereof, lipoic acid and derivatives thereof, dihydrolipoic acid, aurothioglucose, thiols and salts thereof, propylthiouracil, thioredoxin, glutathione, cysteine, cystine, cystamine, glycosyl, N-acetyl, methyl, ethyl, propyl, amyl, butyl and lauryl, palmitoyl, oleyl, gamma-linoleyl, cholesteryl and glyceryl esters of cystamine, dilauryl thiodipropionate, distearyl thiodipropionate, thiodipropionic acid and derivatives thereof, sulfoximine compounds, buthionine sulfoximines, homocysteine sulfoximine, buthionine sulfones, penta-, hexa-, and heptathionine sulfoximines, chelating agents, alpha-hydroxy fatty acids, palmitic acid, phytic acid, lactoferrin, alpha-hydroxy acids, citric acid, lactic acid, malic acid, humic acid, bile acid, bile extracts, bilirubin, biliverdin, EDTA, EGTA and derivatives thereof, unsaturated fatty acids and derivatives thereof, gamma-linolenic acid, linoleic acid, oleic acid, folic acid and derivatives thereof, ubiquinone, ubiquinol and derivatives thereof, vitamin C and derivatives thereof, ascorbyl palmitate, Mg ascorbyl phosphate, ascorbyl acetate, tocopherols and derivatives thereof, vitamin E acetate, vitamin A and derivatives thereof, vitamin A palmitate, coniferyl benzoate of benzoin, rutinic acid and derivatives thereof, alpha-glycosylrutin, ferulic acid, furfurylideneglucitol, carnosine, butylhydroxytoluene, butylhydroxyanisole, nordihydroguaiacic acid, nordihydroguaiaretic acid, trihydroxybutyrophenone, uric acid and derivatives thereof, mannose and derivatives thereof, zinc and derivatives thereof, ZnO, ZnSO₄, selenium and derivatives thereof, selenomethionine, stilbenes and derivatives thereof, stilbene oxide, trans-stilbene oxide, and combinations thereof.

27. The antioxidant flavonoid according to claim 20, which is selected from the group consisting of:

28. A pharmaceutical composition comprising a carrier and an antioxidant flavonoid according to claim 20.

29. A compound having a structure selected from the group consisting of:

30. A pharmaceutical composition comprising a carrier and compound selected from the group consisting of:

31. A method for treating age-related macular degeneration (AMD) comprising administering to a patient in need thereof an amount of a pharmaceutical composition according to claim 30, which amount is sufficient to reduce oxidation of A2E in the patient's retina.

32. A method for modulating photooxidation of A2E comprising providing a photooxidation reducing amount of a compound of formula I, II, or III.

33. The method according to claim 32, wherein the compound is selected from the group consisting of:

34. The method according to claim 32, wherein the providing step comprises administering one or more of the compounds to a cell.

35. The method according to claim 32, wherein the providing step comprises administering one or more of the compounds in a pharmaceutical composition to a patient.

36. The method according to claim 32, wherein the ameliorating is a reduction of photooxidation of A2E.