WO1995022323A1

WO1995022323A1 - Methods for controlling free radical generation by inflammatory cells

Info

Publication number: WO1995022323A1
Application number: PCT/US1995/002065
Authority: WO
Inventors: Walter Dorsch; Hildebert Wagner
Original assignee: Idun Pharmaceuticals
Priority date: 1994-02-16
Filing date: 1995-02-16
Publication date: 1995-08-24
Also published as: AU1846695A

Abstract

Methods, compositions and compounds for the treatment of chronic inflammatory diseases, such as inflammatory bowel disease, are described. The methods, compositions and compounds of the invention are effective to inhibit the oxidative burst pathway.

Description

METHODS FOR CONTROLLING FREE RADICAL GENERATION BY INFLAMMATORY CELLS

BACKGROUND OF THE INVENTION

The present invention relates to compositions and methods for treating inflammatory disorders. More specifically, the present invention concerns the control of the generation of free radicals in the immune response.

Inflammation, a common response of a host to an injury or infection, is identified by four classic symptoms: heat (calor) , redness (rubor) , swelling (tumor) and pain (dolor) . Acute inflammatory response, which is induced by antibodies or other agents, is characterized by a set of rapidly occurring events at the site of injury. Vessels located near the site of the injury dilate, thereby causing redness and heat, allowing an influx of plasma proteins and phagocytic cells into the tissue spaces, thereby causing swelling. Release and/or activation of other inflammation mediators, and increased tissue pressure, stimulate local nerve endings, causing pain.

In infectious situations, if the acute inflammatory response relieves the host of the infectious agent, repair and regeneration ensue. However, if the acute response is not effective in ridding the host of the infection, the continued influx of polymorphonuclear leukocytes and serum products can lead to formation of abscesses and granulomas. The abscess is a swelling which is bounded by fibrin from clotted blood and cells involved in phagocytosis and repair. The central cavity of the abscess contains both live and dead polymorphonuclear leukocytes, tissue debris, and the remaining injurious or infecting agent. The center of the abscess is commonly called pus. Continuing acute inflammatory responses may lead to chronic inflammatory response. These responses have the same four cardinal signs as described above but are composed of additional cellular and soluble mediators. Chronic inflammatory responses are characterized by an infiltration of lymphocytes and cells of monocyte- macrophage lineage in addition to polymorphonuclear cells.

Both acute and chronic inflammation comprise basically three phases. In the first phase, the material to be eliminated (antigen) is recognized as foreign by various mechanisms involving immunoglobulins. Following recognition the second phase of the immune response is initiated, wherein an amplification system involving complement, cytokines, kinins, coagulation, lipid mediators, and a large number of inflammatory cells is activated. This results in an alteration of blood flow, increased vascular permeability, augmented adherence of circulating leukocytes to the vascular endothelium, promotion of migration of leukocytes into tissue, and stimulation of leukocytes to destroy the inciting antigen. During the third phase, destruction of the antigen is mediated by several non-specific mechanisms including phagocytic cells (e.g. , neutrophils, eosinophils and mononuclear phagocytes) . Such phagocytic leukocytes migrate freely or are fixed in tissue sites as components of the mononuclear phagocyte system. Macrophages in related cells, e.g. , Kupffer cells, are central components of the fixed system.

Generally, immune processes are ongoing and usually lead to the elimination of antigens without producing any clinically detectable signs of inflammation. Obvious clinical symptoms often indicate that the immune system has encountered either an unusually large amount of antigen, antigen in an unusual location, or an antigen that is difficult to digest. In some diseases, such as rheumatoid arthritis and inflammatory bowel disease, the inciting antigen is unknown or the inflammatory attack could be against normal host protein. See, Paul, FUNDAMENTAL IMMUNOLOGY 2nd Ed. Raven Press, 1989. The first immune cells to arrive at the site of inflammation are neutrophils, generally within a few hours of tissue injury or infection. Neutrophils are produced in the bone marrow and take approximately two weeks to achieve maturity. The first seven days of neutrophil development are proliferative, and with successive cell division the cells evolve from myeloblasts to promyelocytes and then to myelocytes. During this period neutrophils acquire their characteristic granules. The first granules to appear during neutrophil maturation are called the primary or azurophil granules and comprise about 1/3 of all the granules in the mature cell. Primary granules function predominantly in the intercellular environment, in the phagolysosomal vacuole where they are involved in killing and degrading microorganisms.

When activated, neutrophils and mononuclear phagocytes initiate a process known as the "respiratory burst" or "oxidative burst". In this process, oxygen is reduced to form the superoxide anion (0₂ ^~*) , or its protonated form hydroperoxyl radical (H0₂ ^*) . The superoxide anion is able to pass through cell membranes through anion channels. While the superoxide anion may have some direct toxic effects, it also exerts its toxicity through its conversion to other toxic products known collectively as reactive oxygen species (ROS). Hydrogen peroxide (H₂0₂) is produced from 0₂ ^~* spontaneously, or through the action of superoxide dismutase. The hydrogen peroxide interacts with myeloperoxidase (MPO) to produce hypochlorous acid which is then metabolized to hypochlorite and chlorine. Alternatively, hydrogen peroxide can yield toxic hydroxyl radical as a product of an iron-catalyzed reaction known as the Fenton reaction. Hydroxyl radical and hypochlorite are products of oxygen metabolism which are generally thought to be important in cytotoxic reactions. The toxicity of hydroxyl radical is believed to result from its ability to serve as a powerful one electron oxidant capable of oxidizing a large variety of compounds, thereby forming new radicals. These radicals can proceed to oxidize other substances. The importance of the oxidative burst for microbicidal function is seen from the fact that patients who are congenitally deficient in superoxide production, such as, for example, in cases of chronic granulomatous disease, suffer from recurrent or persistent bacterial infections.

Macrophages perform a similar function to neutrophils as well as more diverse tasks. These ubiquitous and mobile cells continually sample their environment and respond to various stimuli. Macrophages have diverse surface receptors allowing them to respond to many different types of stimuli, e.g.. both exogenous and endogenous proteins, polysaccharides, and lipids. Macrophages are highly active in absorptive endoσytosis or pinocytosis — the uptake of a sample of extracellular fluid without its component molecules first binding to a surface component — and in receptor-mediated endocytosis. An example of endocytosis is the uptake of a range of microorganisms opsonized by antibodies and complement. When these particles are internalized, the above described respiratory burst is initiated, activating a specific membrane oxidase which requires nicotinamide adenine dinucleotide phosphate (NADPH) . This oxidase is often referred to as the "NADPH oxidase" or the "phagocyte oxidase". The active phagocyte oxidase produces large quantities of superoxide radical, which in turn generates the ROS, and which have potent antimicrobial and general cytocidal activity. Thus, the respiratory burst contributes to the killing of some infectious agents by phagocytes.

Unfortunately, many pathologic conditions exist in which the destructive power of macrophages and neutrophils through the respiratory burst serves to destroy otherwise healthy host tissue. For example, severe tissue destruction can result from the binding of complement fixing antibodies to host tissue cells. This binding leads to the deposition of complement fragments on the surface of the cells, whereupon fixed or free phagocytes containing receptors for the complement fragments migrate to the area and release ROS which, together with complement-mediated tissue lysis lead to destruction of host tissues, e.g. , as in systemic lupus erythematosus. ROS are also thought to contribute to tissue damage to the gastrointestinal tract in inflammatory bowel diseases.

Thus, modulating the production and toxicity of ROS by neutrophils and macrophages would offer one method of treating inflammatory diseases such as inflammatory bowel disease. In recent years, three strategies have evolved based on this approach. One such effort has focused on the removal of oxygen radicals with scavenger enzymes such as superoxide dismutase, catalase or similar preparations. Unfortunately, a complicating factor arising in the treatment of chronic inflammatory diseases with these agents is establishing a continuous systemic supply of the scavenger enzymes, as these are rapidly degraded and removed from the body by mechanisms such as digestion by peptidases and the like. Attempts have also been made to identify non-protein mimics of superoxide dismutase.

A second approach has been the prevention of iron-dependent ROS formation by chelation of iron with compounds such as desferrioxa ine. A third approach has been to prevent the generation of radicals by NADPH oxidase through the use of compounds such as diphenylene iodonium. Unfortunately, various side effects complicate the clinical application of these drugs for the treatment of inflammatory diseases.

Thus, it would be advantageous to discover other substances which modulate or otherwise ameliorate the oxidative burst pathway of phagocytes and other types of immune cells for use in treatments for inflammatory diseases such as inflammatory bowel disorder.

SUMMARY OF THE INVENTION

In one aspect, the present invention includes a method effective for modulating oxidative burst in phagocytic cells. The method comprises administering to phagocytic cells an effective amount of a compound having the structure shown in Formula 1:

and its pharmaceutically acceptable salts, wherein R-, R₂, R₄ and R₅ are selected independently from the group consisting of hydrogen, lower alkyl, lower alkoxy, aryl, heteroaryl, arylalkyl, heteroarylalkyl, amino, hydroxy, halo, carboxyl, carbalkoyl, cyano, mercapto, alkylthio, arylthio and amido. R₃ is selected from the group consisting of hydrogen, lower alkyl, lower alkoxy, aryl, heteroaryl, arylalkyl, heteroarylalkyl, amino, hydroxy, halo, carboxyl, carbalkoyl, cyano, mercapto, alkylthio, arylthio, amido and glycosyloxy, and R₆ is selected from the group consisting of lower alkyl, aryl, arylalkyl and heteroarylalkyl. However R₃ is not /3-D-glycosyloxy or hydroxy when R_{l f} R₂ and R₅ are hydrogen, R₄ is methoxy and R₆ is methyl.

In one preferred embodiment, R₃ is glycosyloxy. In a another preferred embodiment, the invention includes compounds having the structure shown in Formula 2:

where n is 1 to 4, R₁₀ is selected from the group consisting of hydroxy, halo, lower alkoxy, mercapto, lower alkylthio, aryloxy and heteroaryloxy, and R_lλ is selected from the group consisting of lower alkyl, aryl, heteroaryl, arylalkyl and heteroarylalkyl.

An especially preferred embodiment is one wherein R₁₀ is hydroxy and R₁₂ is methyl, shown in Formula 3:

In another aspect, the present invention includes a method for treating free-radical-generating inflammatory conditions in an animal which comprises administering to such animal a therapeutically effective amount of a compound having the structure shown in Formula 1. A preferred embodiment of this aspect of the invention is one wherein the compound is that shown in Formula 2. An especially preferred embodiment is one wherein the compound is that shown in Formula 3.

In another aspect, the present invention includes a method for treating asthma in an animal which comprises administering to such animal an effective amount of a compound having the structure shown in Formula 1, but wherein R₃ is not α-L- or /3-D-glycosyloxy or hydroxy when R_ , R₂, R₄ and R₅ are hydrogen, halogen, or lower alkoxy and R₆ is lower alkyl.

In still another aspect, the present invention includes novel compounds having the structure shown in Formula 2. An especially preferred embodiment is one wherein the compound is that shown in Formula 3.

In yet another aspect, the present invention includes compositions and methods for the treatment of inflammatory conditions which comprise the compound shown in Formula 2 and a pharmaceutically acceptable carrier. An especially preferred embodiment is one which includes the compound shown in Formula 3.

A further understanding of the nature and advantages of the invention will become apparent by reference to the remaining portions of the specification and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 shows the relative abilities of several compounds to suppress the release of superoxide anion in neutrophils: androsin (1), apocynin (2), 3,5-dimethoxy-4- hydroxyacetophenone (3) , 4- ( 2-hydroxyethoxy) -3- methoxyacetphenone (4), 2,4-dihydroxy-3-methylacetophenone (5), and 2-hydroxy-4-methoxyaceto.phenone (6).

Figure 2 shows the relative dose-response characters of several compounds with respect to suppressing the release of superoxide anion: androsin (1), apocynin (2), 3,5-dimethoxy-4-hydroxyacetophenone (3), 4-(2- hydroxyethoxy)-3-methoxyacetphenone (4), 2,4-dihydroxy-3- methylacetophenone (5), and 2-hydroxy-4-methoxyacetophenone (6).

DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS

I. Definitions

The following definitions are set forth to illustrate and define the meaning and scope of the various terms used to describe the invention herein.

"Inflammatory condition" includes generally those conditions associated with tissue destruction caused by phagocytic action. Examples of such disorders include asthma, peptic ulcers, inflammatory bowel disorder, rheumatoid arthritis, reperfusion injury, inflammatory skin conditions, and the like.

"Halo" refers to fluorine, bromine, chlorine, and iodine atoms.

"Hydroxyl" refers to the group -OH. "Lower alkoxy" refers to the group -OR, where R is lower alkyl as defined below.

"Acyloxy" refers to the group -OR, where R is aryl, heteroaryl, arylalkyl, and heteroarylalkyl as defined below.

"Mercapto" or "Thio" refers to the group - SH.

"Lower alkylthio" refers to the group -SR, where R is lower alkyl as defined below. "Arylthio" refers to the group -SR, where R is where R is aryl, heteroaryl, arylalkyl, and heteroarylalkyl as defined below.

"Amino" refers to the group -NRR' where R and R' independently are hydrogen, lower alkyl, aryl, heteroaryl, arylalkyl, and heteroarylalkyl as defined below.

"Carboxyl" refers to the group -C0₂H.

"Carbalkoyl" refers to the group -C0₂R where R is hydrogen, lower alkyl, aryl, heteroaryl, arylalkyl, and heteroarylalkyl as defined below.

"Cyano" refers to the group -CN.

"Glycosyl" refers to a saccharide group bound at the 1-carbon of the saccharide ring. "Glycosyloxy" refers to the group -OR, wherein R is glycosyl.

"Lower alkyl" refers to a cyclic, branched or straight chain alkyl group of one to six carbon atoms. This term is further exemplified by such groups as methyl, ethyl, n-propyl, i-propyl, n-butyl, t-butyl, i-butyl (or 2-methylpropyl) , cyclopropylmethyl, i-amyl, n-amyl, and hexyl.

"Aryl" or "Ar" refers to an aromatic carbocyclic group having a single ring (e.g. , phenyl) or multiple condensed rings in which at least one ring is aromatic, (e.g. , 1,2,3, -tetrahydronaphthyl, naphthyl, anthryl, or phenanthryl) , which can optionally be unsubstituted or substituted with, e.g. , halogen, lower alkyl, lower alkoxy, lower alkylthio, trifluoromethyl, lower acyloxy, and hydroxy.

"Heterocycle" refers to a saturated, unsaturated, or aromatic carbocyclic group having a single ring (e.g. , morpholino, pyridyl or furyl) or multiple condensed rings (e.g.. naphthyridinyl, quinoxalyl, quinolinyl, indolizinyl or benzo[b]thienyl) and having at least one hetero atom, such as N, 0 or S, within the ring, which can optionally be unsubstituted or substituted with, e.g. , halo, lower alkyl, lower alkoxy, lower alkylthio, trifluoromethyl, lower acyloxy, and hydroxy. The term "heteroaryl" or "HetAr" refers to a heterocycle in which at least one heterocyclic ring is aromatic.

"Arylalkyl" or "aralkyl" refers to the group -R-Ar where Ar is an aryl group and R is straight-chain or branched-chain aliphatic group. Arylalkyl groups can optionally be unsubstituted or substituted with, e.g.. halo, lower alkyl, lower alkoxy, lower alkylthio, trifluoromethyl, lower acyloxy, and hydroxy.

"Heteroarylalkyl" refers to the group -R-HetAr where HetAr is an heteroaryl group and R is straight-chain or branched-chain aliphatic group. Heteroarylalkyl groups can optionally be unsubstituted or substituted with, e.g. , halo, lower alkyl, lower alkoxy, lower alkylthio, trifluoromethyl, lower acyloxy, and hydroxy.

"Pharmaceutically acceptable salt" refers to those salts which retain the biological effectiveness and properties of the parent compound and which are not biologically or otherwise undesirable.

"Pharmaceutically or therapeutically acceptable carrier" refers to a carrier medium which does not interfere with the effectiveness of the biological activity of the active ingredients and which is not toxic to the host or patient.

"Stereoisomer" refers to a chemical compound having the same molecular weight, chemical composition, and connectivity as first compound, but with the ability to rotate the plane of polarized light differently from the first compound. The compounds of the instant invention may have one or more asymmetrical carbon atoms and are defined herein to include all of their various stereoisomers.

"Treatment" or "treating" refers to any administration of a compound of the invention in vitro or in vivo and includes:

(i) inhibiting the symptoms of the disease;

(ii) lessening or inhibiting the long term effects of the disease.

II. Methods and Compositions of the Invention

In one aspect, the present invention includes methods effective for modulating oxidative burst in phagocytic cells, comprising administering to such cells an effective amount of a compound having the structure shown in Formula 1:

and its pharmaceutically acceptable salts, wherein R_lf R₂, R₄ and R₅ are selected independently from the group consisting of hydrogen, lower alkyl, lower alkoxy, aryl, heteroaryl, arylalkyl, heteroarylalkyl, amino, hydroxy, halo, carboxyl, carbalkoyl, cyano, mercapto, alkylthio, arylthio and amido; R₃ is selected from the group consisting of hydrogen, lower alkyl, lower alkoxy, aryl, heteroaryl, arylalkyl, heteroarylalkyl, amino, hydroxy, halo, carboxyl, carbalkoyl, cyano, mercapto, alkylthio, arylthio, amido and glycosyloxy; and R₆ is selected from the group consisting of lower alkyl, aryl, arylalkyl and heteroarylalkyl. Provided, however, that R₃ is not /3-D-glycosyloxy or hydroxy when R-, R₂ and R₅ are hydrogen, R₄ is methoxy and R₆ is methyl.

In one preferred embodiment, R₃ is glycosyloxy. In another preferred embodiment, the invention includes compounds having the general structure shown in Formula 4:

wherein R₇ is selected from the group consisting of hydrogen, lower alkyl, lower alkoxy, aryl, heteroaryl, arylalkyl, heteroarylalkyl, amino, hydroxy, halo, carboxyl, carbalkoyl, cyano, mercapto, alkylthio, arylthio, amido and glycosyloxy; R₈ is selected independently from the group consisting of hydrogen, lower alkyl, lower alkoxy, aryl, heteroaryl, arylalkyl, heteroarylalkyl, amino, hydroxy, halo, carboxyl, carbalkoyl, cyano, mercapto, alkylthio, arylthio and amido; and R₉ is selected from the group consisting of lower alkyl, aryl, arylalkyl and heteroarylalkyl lower alkyl. A preferred embodiment of the structure shown in Formula 4 is one wherein R₉ is methyl.

An especially preferred embodiment of the invention includes a compound having the structure shown in Formula 2:

wherein n is 1 to 4; R₁₀ is selected from the group consisting of hydroxy, halo, lower alkoxy, mercapto, lower alkylthio, aryloxy and heteroaryloxy; and R_ια is selected from the group consisting of lower alkyl, aryl, heteroaryl, arylalkyl and heteroarylalkyl. An especially preferred embodiment includes the compound shown in Formula 3:

In another aspect, the method of modulating oxidative burst may include a compound having the structure shown in Formula 5:

wherein R₁₂ is selected from the group consisting of hydrogen, lower alkyl, lower alkoxy, aryl, heteroaryl, arylalkyl, heteroarylalkyl, amino, hydroxy, halo, carboxyl, carbalkoyl, cyano, mercapto, alkylthio, arylthio, amido and glycosyloxy; R₁₃ and R₁₄ are selected independently from the group consisting of hydrogen, lower alkyl, lower alkoxy, aryl, heteroaryl, arylalkyl, heteroarylalkyl, amino, hydroxy, halo, carboxyl, carbalkoyl, cyano, mercapto, alkylthio, arylthio and amido; and R₁₅ is selected from the group consisting of lower alkyl, aryl, arylalkyl and heteroarylalkyl. Provided, however, that R₁₂ is not /3-D- glycosyloxy or hydroxy when R₁₄ is hydrogen, R₁₃ is methoxy and R₁₅ is methyl.

A preferred embodiment is one wherein R₁₅ is methyl. Another preferred embodiment is one wherein R₁₂ and R₁₄ are hydroxy, and R₁₃ and R₁₅ are methyl, as shown in Formula 6 below:

Formula 6

In another embodiment, the present invention includes compounds having the structure shown in Formula 7:

wherein R₁₆ ,R₁₈ and R₁₉ are selected independently from the group consisting of hydrogen, lower alkyl, lower alkoxy. aryl, heteroaryl, arylalkyl, heteroarylalkyl, amino, hydroxy, halo, carboxyl, carbalkoyl, cyano, mercapto, alkylthio, arylthio and amido; R₁₇ is selected from the group consisting of hydrogen, lower alkyl, lower alkoxy, aryl, heteroaryl, arylalkyl, heteroarylalkyl, amino, hydroxy, halo, carboxyl, carbalkoyl, cyano, mercapto, alkylthio, arylthio, amido and glycosyloxy; and R₂₀ is selected from the group consisting of lower alkyl, aryl, arylalkyl and heteroarylalkyl. Provided, however, that R₁₇ is not /3-D-glycosyloxy or hydroxy when R₁₆ and R₁₉ are hydrogen, R_1S is methoxy and R₂₀ is methyl, In a preferred embodiment, R₂₀ is methyl.

Other preferred compounds are those where R₁₆ and R₁₈ are methoxy and R₁₇ is hydroxy, and those where R₁₆ and R₁₈ are hydrogen, R₁₇ is methoxy, and R₁₉ is hydroxy, as shown in Formulas 8 and 9 respectively:

In still another aspect, the present invention includes compounds having the chemical structure shown in Formula 2. A preferred embodiment in one wherein R₁₀ is hydroxy and R_1X is methyl as shown in Formula 3.

III. Formulations

According to one aspect of the invention, a therapeutically or pharmaceutically effective amount of one or more of the compounds described above is administered to an animal suffering from a free-radical-generating inflammatory condition, such as, but not limited to, inflammatory bowel disease, rheumatoid arthritis, burn injury, inflammatory side effects resulting from radiation and/or chemotherapy, secondary tissue damage following immunologic inflammation or infectious disease, osteomyelitis, granulomatous disease, hepatitis, pancreatitis, lupus erythematosus, autoimmune dermatitis, or reperfusion injury following heart attack or stroke. The compounds of the invention are also useful in the treatment of asthma. In using the compositions of the present invention in a treatment of such conditions, the compounds may be administered prophylactically prior to exposure to a precipitating factor, during exposure or after such exposure. The compounds of the instant invention are particularly useful in ameliorating the tissue destruction seen in free-radical-generating inflammatory disorders and the like.

The compositions containing the compounds described above can be administered f r prophylactic and/or therapeutic treatments. In therapeutic applications, compositions are administered to a patient already suffering from a condition, as described above, in an amount sufficient to cure or at least partially arrest the symptoms of the condition and its complications. An amount adequate to accomplish this cure or arrest is defined as "therapeutically effective amount or dose." Amounts effective for this use will depend on the severity and course of the disease, previous therapy, the patient's health status and response to the drugs.

Once improvement of the patient's conditions has occurred, a maintenance dose is administered if necessary. Subsequently, the dosage or the frequency of administration, or both, can be reduced, as a function of the symptoms, to a level at which the improved condition is retained. When the symptoms have been alleviated to the desired level, treatment can cease. Patients can, however, require intermittent treatment on a long-term basis upon any recurrence of the disease symptoms.

In general, a suitable effective dose will be in the range of 0.1 to 1000 milligram (mg) per recipient per day, preferably in the range of 1 to 100 mg per day. The desired dosage is preferably presented in one, two, three, four or more subdoses administered at appropriate intervals throughout the day. These subdoses can be administered as unit dosage forms, for example, containing 5 to 1000 mg, preferably 10 to 100 mg of active ingredient per unit dosage form.

The composition used in these therapies can be in a variety of forms. These include, for example, solid, semi-solid and liquid dosage forms, such as tablets, pills, powders, liquid solutions or suspensions, emulsions, liposomes, injectable and infusible solutions. The preferred form depends on the intended mode of administration and therapeutic application.

While it is possible to administer the active ingredient of this invention alone, it is preferable to present it as part of a pharmaceutical formulation. The formulations of the present invention comprise at least one compound or modulator of oxidative burst described herein in a therapeutically or pharmaceutically effective dose together with one or more pharmaceutically or therapeutically acceptable carriers and optionally other therapeutic ingredients. Various considerations for making such formulations are described, e.g. , in Gilman, et al. (eds) (1990) GOODMAN AND GILMAN's: THE PHARMACOLOGICAL BASES OF THERAPEUTICS, 8th Ed., Pergamon Press; and REMINGTON'S PHARMACEUTICAL SCIENCES 18th Ed., Mack Publishing Company (1990). Methods for administration are discussed therein, e.g. , for oral, intravenous, intraperitoneal, intracolo ic or intramuscular administration, and others. Pharmaceutically acceptable carriers will include water, saline, buffers, and other compounds described, e.g. , in the MERCK INDEX, 11th Ed. Merck & Co., Rahway, NJ (1991).

It should, of course, be understood that the methods of this invention can be -sed in combination with other agents for the treatment of immunomediated inflammatory conditions, and particularly inflammatory bowel disease and asthma. /3-Adrenergic agonists are especially useful in these combinations, because they provide symptomatic relief of the initial asthmatic response, whereas the compounds of the present invention provide relief for the late asthmatic response. Preferred 3-adrenergic agonists in these solutions include any of the usual /3-agonists employed for the relief of asthma, such as, but not limited to, albuterol, terbutaline, formoterol, fanoterol, or prenaline.

Other agents useful in combination with the compounds of the instant invention include anticholinergics, such as ipratropium bromide, and antiinflammatory corticosteroids (adrenocortical steroids) such as, but not limited to, beclomethasone, triamcinolone, flurisolide, or dexamethasone.

The compounds of the invention can also be used in the treatment of immunomediated inflammatory skin conditions, such as urticaria and angioedema, eczematous dermatitis, and hyperproliferative skin disease, e.g. , psoriasis, in mammals. As a result of the topical administration of a compound of the invention, a remission of the symptoms can be expected. Thus, one affected by an immunomediated inflammatory skin condition can expect a decrease in scaling, erythema, size of the plaques, pruritus, and other symptoms associated with the skin condition. The dosage of medicament and the length of time required for successfully treating each individual patient may vary, but those skilled in the art will be able to recognize these variations and adjust the course of therapy accordingly.

Also included within the invention are preparations for topical application to the skin comprising a compound of the invention, typically in concentrations in the range of from about 0.001% to 10%, together with a non- toxic, pharmaceutically acceptable topical carrier. These topical preparations can be prepared by combining an active ingredient according to this invention with conventional pharmaceutical diluents and carriers commonly used in topical dry, liquid, cream and aerosol formulations. Ointment and creams may, for example, be formulated with an aqueous or oily base with the addition of suitable thickening and/or gelling agents. Such bases may include water and/or an oil such as liquid paraffin or a vegetable oil such as peanut oil or castor oil. Thickening agents which may be used according to the nature of the base include soft paraffin, aluminum stearate, cetostearyl alcohol, propylene glycol, polyethylene glycols, woolfat, hydrogenated lanolin, beeswax, and the like.

Lotions may be formulated with an aqueous or oily base and will, in general, also include one or more of the following: stabilizing agents, emulsifying agents, dispersing agents, suspending agents, thickening agents, coloring agents, perfumes, and the like.

Powders may be formed with the aid of any suitable powder base, e.g. , talc, lactose, starch, and the like. Drops may be formulated with an aqueous base or non- aqueous base also comprising one or more dispersing agents, suspending agents, solubilizing agents, and the like.

The topical pharmaceutical compositions according to this invention may also include one or more preservatives or bacteriostatic agents, e.g. , methyl hydroxybenzoate, propyl hydroxybenzoate, chlorocresol, benzalkonium chlorides, and the like. The topical pharmaceutical compositions also can contain other active ingredients such as antimicrobial agents, particularly antibiotics, anesthetics, analgesics, and antipruritic agents.

The pharmaceutical compositions can be administered by parenteral, inhalation, suppository or oral administration for prophylactic and/or therapeutic treatment. The pharmaceutical compositions can be administered in a variety of unit dosage forms depending upon the method of administration. For example, unit dosage forms suitable for oral administration include powder, tablets, pills, capsules and dragees.

The pharmaceutical compositions can be administered intravenously. Thus, this invention provides compositions for intravenous administration which comprise a solution of the compound dissolved or suspended in an acceptable carrier, preferably an aqueous carrier. A variety of aqueous carriers can be used, e.g. , water, buffered water, 0.4% saline, and the like. These compositions will sometimes be sterilized by conventional, well known sterilization techniques, or can be sterile filtered. The resulting aqueous solutions can be packaged for use as is, or lyophilized, the lyophilized preparation being combined with a sterile aqueous solution prior to administration. The compositions can contain pharmaceutically acceptable auxiliary substances as required to approximate physiological conditions, such as pH adjusting and buffering agents, tonicity adjusting agents, wetting agents and the like, for example, sodium acetate, sodium lactate, sodium chloride, potassium chloride, calcium chloride, sorbitan monolaurate, triethanolamine oleate, and the like.

For solid compositions, conventional nontoxic solid carriers can be used which include, for example, pharmaceutical grades of mannitol, lactose, starch, magnesium stearate, sodium saccharin, talcum, cellulose, glucose, sucrose, magnesium carbonate, and the like. For oral administration, a pharmaceutically acceptable nontoxic composition is formed by incorporating any of the normally employed excipients, such as those carriers previously listed, and generally 0.1-95% of active ingredient, preferably about 20%.

EXAMPLES The following examples are provided solely for the purposes of illustrating the invention and are not meant to limit the scope of the invention in any way.

A. Synthesis

The compounds described above may be synthesized using techniques known in the art for making substituted acetophenones, by analogy to the Examples illustrated below and published syntheses. See, e.g. , March, ADVANCED ORGANIC CHEMISTRY 4th Ed., Wiley 1991; and U.S. Patent Nos. 4,661,505 and 4,777,299 both to Marshall, et al., ("Marshall"), all of which are incorporated herein by reference. Some of the compounds of the invention are available commercially from suppliers such as Aldrich (Milwaukee, WI) and Sigma (St. Louis, MO).

Specifically, compounds such as those shown in Formulas 2, 3 and 4 may be synthesized from commercially-available starting materials by analogy to the techniques described in Marshall or in Example III below. Some of these compounds may also be purchased commercially. For example, the compound of Formula 3 (or its trimethylsilyl derivative) may be formed by combining equimolar amounts of 3-methoxyacetophenone with 2- chloroethanol or 2-choiorethxoytrimethylsilane (available from Aldrich) in an inert ketone solvent such as acetone containing a small amount of a base such as potassium carbonate. It will be appreciated that if trimethylsilyl derivative is made, deprotection to form the final product may be performed using well-known procedures for removing the trimethylsilyl protecting groups, such as those described in Green and Wuts, PROTECTIVE GROUPS IN ORGANIC SYNTHESIS (Wiley 1991), incorporated herein by reference.

The glycosyloxy derivatives of the invention may be made by analogy to the syntheses of /3-D-glycoside derivatives which are described in detail below.

EXAMPLE I General procedures for the synthesis of 3-D-glvcosyloxy derivatives

-acetobromoglucose acβtonθ/2.5% KOH

IN NaOCH₃ CH3OH

Scheme I

With reference to Scheme I (R represents any substituent) , aqueous potassium hydroxide solution (18 mmol, 2.5%) was added at room temperature (r.t.) to a solution of substituted phenol 1 (10 mmol) in acetone (10-15 ml). A solution of α-acetobromoglucose (14-16 mmol) in acetone (20-30 ml) was next added dropwise while stirring and the stirring was continued for 24-40 h. The mixture was neutralized with 10% hydrochloric acid and cooled to 0°C. The crude product was either filtered off, or, if it did not precipitate on cooling, extracted with ethyl acetate followed by evaporation in vacuo. On crystallization from methanol the acetylglycosyltetraacetates 2 were achieved in yields of 20-45%.

The glycosidic acetates were removed using the following procedure. To a methanol solution of the tetraacetylglycosides (2 mmol) sodium methoxide (9 mmol) was added and stirred for 2-3 h. The mixture was neutralized with ion-exchange resin (1R-120) and the solvent evaporated at r.t. i-n vacuo. Crystallization from hot water provided the desired phenylglycosides 3 in yields of 70-80%.

EXAMPLE II General Procedure For the Synthesis of Aceto- and Propio- phenone Derivatives

Referring now to Scheme II, a solution of benzaldehyde derivative 4 (10 mmol, R' = CH₃, CH₂CH₃) in dimethylformamide (10 ml) was refluxed with benzylchloride (10.5 mmol) in the presence of K₂C0₃ for 30 min. After cooling it was poured into water (300 ml) and the precipitated crude material filtered off. On crystallization from methanol the white crystalline product 5 were obtained.

To an suspension of Mg in ether, a solution of methyl- or ethyl bromide was added to form the corresponding Grignard reagent R"MgX (R" = CH₃, CH₂CH₃, X = Br) . An ether solution of the equimolar quantity of benzylbenzaldehyde 5 was added dropwise. The solution was maintained in a gentle reflux and stirred for an additional 30 minutes. On cooling a saturated aqueous solution of NH₄C1 was added and the solvent layer decanted. The slurry was stirred with ether and extracted twice more to isolate all of the alcohol 6 produced. The alcohol could be submitted without purification to the oxidation process.

Alcohol 6 (12 mmol) was solvated in dry dichloromethane and while stirring a great excess of activated Mn0₂ was added and stirring continued for 14-60 h, followed by TLC. The inorganic component was filtered off, the solvent evaporated in vacuo and the crude product was crystallized from ethanol to provide the protected aceto- or propiophenones 7.

Deprotection by removal of the benzyl group was carried out by boiling the benzyl ether (6 mmol) in a mixture of acetic acid:hydrochloric acid (3:1 = 60 ml) for 30 min. To the cooled solution water (300 ml) was added and this was extracted with chloroform three times. The combined organic solution was first washed with a 2% NaHC0₂ solution, then with water, and dried on MgS0₄. The solvents were evaporated in vacuo. The desired phenol 8 was obtained as a solid and was purified on a silica gel column using toluene-ethyl acetate. EXAMPLE III

Preparation of the -salt of the 4-carboxymethyl

Acetovanillin and of the 4-hydroxyethyl Acetovanillin

11

Scheme III

As shown above in Scheme III , vanillin 9 (10 mmol) was dissolved in acetone (10 ml). A large excess of ethyl chloroacetate (20 mmol) was added, and the mixture was stirred under reflux in the presence of 3 g of K₂C0₃ and 0.1 g of KI for 4h. The salts were filtered off, the solution evaporated at r.t. in vacuo, water was added and the solid filtered off. Crystallization from methanol provided the ethoxycarboxyl derivative 10 having a m.p. of 67-69°C.

To a stirred suspension of lithium aluminum hydride (200 mg) in ethyl ether (20 ml) a solution of 10 (2 mmol) in ether (42 ml) was added dropwise. The reaction time, as followed by thin-layer chromatography (TLC), was about lh. After workup (decomposition of the excess hydride with ethyl acetate and addition of saturated aq. NH₄C1 solution) the ether layer was decanted, the slurry twice more stirred with ethyl acetate and the combined organic solution washed with water, dried on MgS0₄ and. evaporated in vacuo. The crude diol formed was submitted without purification to the oxidation process.

To oxidize the diol to the desired product, the diol obtained was dissolved in dry dichloromethane and active Mn0₂ (1.5 g) was added to the solution while stirring. An additional Ig of Mn0₂ was added after 2Oh and the reaction quenched after 7Oh. On workup the Mn salt was boiled with a mixture of methanol- ethyl acetate to produce the desired product 11 (m.p. 93- 96°). This is the compound shown above in Formula 3.

Alternatively, saponification of ester 10 to form carboxylate salt 12 was achieved by boiling 10 (2 mmol) in an ethanol solution of potassium hydroxide (21 ml, 560 mg KOH/100 ml EtOH) for 6 h to provide, after evaporation of the solvent, the potassium salt 12. This product decomposed on melting.

EXAMPLE IV 5-Halogen-Substituted Acetovanillins

X = Br 14 X = CI 15

Scheme IV Scheme IV illustrates the general synthetic procedures for forming 5-haloacetovanillins. It will be appreciated that halogen substitutions at other ring positions may be made by analogy to the examples described below.

5-iodoacetovanillin

Acetovanillin 9 (10 mmol) was dissolved in water (75 ml) containing sodium acetate (1.5 g) , potassium fluoride (KF, 0.5g). Iodine (10 mmol) was added, and the mixture was stirred at 90°C for 3h. On cooling the solution was extracted with chloroform, washed with aq. Na₂S₂0₃, followed by water. The solution was dried over MgS0₄ and the solvent evaporated in vacuo. The desired product 13 was crystallized from acetic acid to furnish crystals of the desired product having a m.p. 174-176°C.

5-bromoacetovanillin

Acetovanillin 9 (10 mmol) was solvated in a mixture of methanol (80 ml) and water (10 ml) containing sodium acetate (1.5g). Potassium bromide (0.5 g) was added and the mixture stirred and cooled to -60°C. At this temperature 0.7 ml bromine was added dropwise to the solution. The workup was the same as described above, affording crystals of the desired brominated product 14, having a m.p. 155-157°C.

5-chloroacetovanillin

Acetovanillin 9 (10 mmol) was dissolved in methanol (80 ml). Sodium acetate (3g) was added to the solution and the mixture was stirred at -60°C. Sodium hypochlorite solution (35 ml, 35% was added dropwise to the mixture over a period of 1.5 h. The workup was the same as above, resulting in crystals of the desired product 14 which had a m.p. 124-126°C. B. Suppression of Oxidative Burst

Human neutrophils were obtained by the following procedure. From the peripheral blood of healthy volunteers anticoagulated with ethylenediaminetetraacetic acid (EDTA, Sigma) , polymorphonucleocytes (PMN) were obtained after discontinuous density gradient centrifugation of whole blood on Percoll (Pharmacia) or from buffy coat residues (mixed with normal saline in a ratio of 3:1) by dextran sedimentation and centrifugation through a layer of

Ficol-Hypaque (Pharmacia) , followed by hypotonic lysis of contaminating erythrocytes using distilled water. The cell preparations (ca. 95% neutrophils by morphology in Giemsa stains, > 99% viable by trypan dye exclusion) were resuspended in hepes buffered saline solution (HBSS) for respiratory burst activity assays. The assays were performed in medium which contained the test substances or their appropriate vehicles.

Measurement of the production of 0₂ ^~ was based on the reduction of ferricytochrome-c by 0₂". The specificity of reduction was controlled by the inhibition of superoxide dismutase (SOD) . Immediately after preparation of PMN, with or without exposure to test substances, 100 μl/well of 2 x 10⁶ PMN cells/ml were immersed in a 160 μM solution of ferricytochrome-c in phenol red-free HBSS containing 10 μM N- formylmethionylleucylphenylalanine (FMLP) at two different concentrations or vehicle alone were added to the wells. To one vertical row cytochrome-c containing 300 U/ml SOD was added to serve as a blank. The plates were covered with lids and placed in a 37 ec humidified incubator with 95% air/5% C0₂ atmosphere. At indicated time intervals, the plates were transferred to an ELISA reader and the absorbances were measured at 550 nm. The absorbance values were converted to nanomoles of 0₂" based on the extinction coefficient (reduced minus oxidized) cytochrome-c according to the form_xia: OD_550rm = 21 x 10³ M^cm^-1. Since the vertical light path passing through 100 ml cytochrome-c was 3 mm, the calculated concentration of 0₂" (nmol/well) was determined using the following relation: [0₂~] = absorbance x 15.87.

The results are illustrated in Figure 1 for androsin (1), apocynin (2), 3,5-dimethoxy-4- hydroxyacetophenone (3), 4-(2-hydroxyethoxy)-3- methoxyacetphenone (4), 2,4-dihydroxy-3- methylacetophenone (5), and 2-hydroxy-4- methoxyacetophenone (6) . Each of these compounds was tested at a concentration of 100 μM. Each of these compounds was found to suppress the production of superoxide ion relative to control.

C. Dose-Response Characteristics

The same procedures described above were also applied to compounds (1) through (6) to determine the dose-response characters of each compound. Concentrations of 1, 10 and 100 μM were studied. The results are shown in Figure 2. As the figure illustrates, only the compound shown in Formula 3 exhibited an ability to suppress superoxide anion below 50% of the control at a concentration of 10 μM, showing superior dose-response characteristics compared to the other compounds studied.

D. Asthma

The compounds of the invention have also been demonstrated in vitro to possess anti-asthma properties. These properties have been illustrated using two different challenges, the results of which are shown in Table 1 below. Male Pirbright white guinea pigs were sensitized to ovalbumin as described in Dorsch, et al. , Pflϋgers Arch 391:236-241 (1981). Inhalation challenge experiments were performed 4-6 weeks following sensitization. Breathing animals were placed in a two- chambered body plethysmograph, both chambers being separated by a water filled rubber cuff around the head of the animal. Volume changes in both chambers were measured by pressure transducers. The degree of bronchial obstruction was estimated by determining the amount of "compressed air". This technique was shown to be about 10 times more sensitive than other invasive methods (Dorsch 1981). Groups of animals were divided into two subgroups and treated either with the test material or control solutions. 3 or 4 days later the tests were repeated in which those animals receiving test compounds were treated with control solution and those animals previously treated with control solutions received test compounds.

Respiratory hyperreactivity in the test animals was induced by exposing the animals to aerosolized ovalbumin and platelet activating factor (PAF) (see, W. Dorsch et aJL. , Int. Arch Allergy Appl. Immunol. (1991) 95:128-133 and W. Dorsch et al., Ibid, (1992) !£:493-495) • The ovalbumin administered to the animals was in the form of a saline solution, 1:99 w/v. Platelet activating factor (PAF) was delivered as a solution formed by dissolving PAF first in ethanol and then in saline containing 0.25% bovine serum albumin yielding a final concentration of Iμg PAF per ml.

The solutions of ovalbumin and PAF were delivered to the test animals as aerosols. Compounds were tested for their ability to block the effects of ovalbumin or PAF challenge. The compounds were administered, either orally or by inhalation, at 30 min, 1 hour, 6 hours and 12 hours prior to challenge. The ovalbumin was administred as a pair of challenges, separated by 15-minutes. All data is presented as mean values with standard deviation. The statistical significance of differences was estimated using the Student's t test for unpaired data. The degree of percent inhibition was calculated for each test separately and is shown as mean ± standard deviation. The statistical significance of percent inhibition was estimated by the Student's t test and Wilcoxon's test for paired data.

Table 1 shows the results of the studies. There, the compound of the invention, 4-(2- hydroxyethoxy)-3-methoxyacetophenone was shown to have significant ability to inhibit asthmatic responses in challenged animals.

This compound inhibited first and second ovalbumin challenges by 51% and 57% respectively when administered by inhalation, and produced 70% inhibition in PAF-induced hyperreactivity.

Table I

Tabulated activities of acetophenones in the "compressed-air-model"

Time prior to OA 1st Chall. OA 2nd Chall. PAF Chall.

Compound Route mg/kg challenge % Inhibition % Inhibition % Inhibition

4-(2-hydroxyethoxy)-3- inhal 0.5 0.5h 51 +56 57 +61 70 +44 methoxy)-3- ethoxyacetophenone

Thus it is seen that the invention provides methods, compositions and compounds which provide a treatment for chronic inflammatory disorders such as inflammatory bowel disease and asthma.

The disclosures in this application of all articles and references, including patents and patent applications, are incorporated herein by reference.

Although the foregoing invention has been described in some detail by way of illustration and example, for purposes of clarity of understanding, it will be obvious that certain changes and modifications may be practiced within the scope of the appended claims.

Claims

WHAT IS CLAIMED IS:

1. A method of modulating oxidative burst in phagocytic cells, comprising administering to such cells an effective amount of a compound having the structure:

and its pharmaceutically acceptable salts, wherein R₁₇ R_2/ R₄ and R₅ are selected independently from the group consisting of hydrogen, lower alkyl, lower alkoxy, aryl, heteroaryl, arylalkyl, heteroarylalkyl, amino, hydroxy, halo, carboxyl, carbalkoyl, cyano, mercapto, alkylthio, arylthio and amido; R₃ is selected from the group consisting of hydrogen, lower alkyl, lower alkoxy, aryl, heteroaryl, arylalkyl, heteroarylalkyl, amino, hydroxy, halo, carboxyl, carbalkoyl, cyano, mercapto, alkylthio, arylthio, amido and glycosyloxy; and R₆ is selected from the group consisting of lower alkyl, aryl, arylalkyl and heteroarylalkyl; provided that R₃ is not /3-D-glycosyloxy or hydroxy when R-, R₂ and R₅ are hydrogen, R₄ is methoxy and R₆ is methyl.

2. The method of claim 1, wherein R₃ is glycosyloxy.

3. The method of claim 1, wherein said compound has the structure:

wherein R₇ is selected from the group consisting of hydrogen, lower alkyl, lower alkoxy, aryl, heteroaryl, arylalkyl, heteroarylalkyl, amino, hydroxy, halo, carboxyl, carbalkoyl, cyano, mercapto, alkylthio, arylthio, amido and glycosyloxy; R₈ is selected independently from the group consisting of hydrogen, lower alkyl, lower alkoxy, aryl, heteroaryl, arylalkyl, heteroarylalkyl, amino, hydroxy, halo, carboxyl, carbalkoyl, cyano, mercapto, alkylthio, arylthio and amido; and R₉ is selected from the group consisting of lower alkyl, aryl, arylalkyl and heteroarylalkyl lower alkyl.

4. The method of claim 3, wherein R₉ is methyl.

5. The method of claim 4, wherein said compound has the structure:

wherein n is 1 to 4; R₁₀ is selected from the group consisting of hydroxy, halo, lower alkoxy, mercapto, lower alkylthio, aryloxy and heteroaryloxy; and R is selected from the group consisting of lower alkyl, aryl, heteroaryl, arylalkyl and heteroarylalkyl.

6. The method of claim 5, wherein said compound has the structure:

7. The method of claim 1, wherein said compound has the structure:

wherein R₁₂ is selected from the group consisting of hydrogen, lower alkyl, lower alkoxy, aryl, heteroaryl, arylalkyl, heteroarylalkyl, amino, hydroxy, halo, carboxyl, carbalkoyl, cyano, mercapto, alkylthio, arylthio, amido and glycosyloxy; R₁₃ and R₁₄ are selected independently from the group consisting of hydrogen, lower alkyl, lower alkoxy, aryl, heteroaryl, arylalkyl, heteroarylalkyl, amino, hydroxy, halo, carboxyl, carbalkoyl, cyano, mercapto, alkylthio, arylthio and amido; and R₁₅ is selected from the group consisting of lower alkyl, aryl, arylalkyl and heteroarylalkyl; provided, however, that R₁₂ is not /3-D-glycosyloxy or hydroxy when R₁₄ is hydrogen, R_α3 is methoxy and R₁₅ is methyl.

8. The method of claim 7, wherein R₁₅ is methyl.

9. The method of claim 8, wherein said compound has the structure:

10. The method of claim 1, wherein said compound has the structure:

wherein R₁₆, R₁₈ and R₁₉ are selected independently from the group consisting of hydrogen, lower alkyl, lower alkoxy, aryl, heteroaryl, arylalkyl, heteroarylalkyl, amino, hydroxy, halo, carboxyl, carbalkoyl, cyano, mercapto, alkylthio, arylthio and amido; R₁₇ is selected from the group consisting of hydrogen, lower alkyl, lower alkoxy, aryl, heteroaryl, arylalkyl, heteroarylalkyl, amino, hydroxy, halo, carboxyl, carbalkoyl, cyano, mercapto, alkylthio, arylthio, amido and glycosyloxy; and R₂₀ is selected from the group consisting of lower alkyl, aryl, arylalkyl and heteroarylalkyl; provided, however, that R₁₇ is not /3-D-glycosyloxy or hydroxy when R_α6 and R₁₉ are hydrogen, R₁₈ is methoxy and R₂₀ is methyl.

11. The method of claim 10, wherein R₂₀ is methyl.

12. The method of claim 11, wherein said compound has the structure:

13. The method of claim 10, wherein said compound has the structure:

14. A method of treating free-radical- generating inflammatory conditions in an animal, comprising administering to such animal an effective amount of a compound having the structure:

and its pharmaceutically acceptable salts, wherein R-, R₂, R₄ and R₅ are selected independently from the group consisting of hydrogen, lower alkyl, lower alkoxy, aryl. heteroaryl, arylalkyl, heteroarylalkyl, amino, hydroxy, halo, carboxyl, carbalkoyl, cyano, mercapto, alkylthio, arylthio and amido; R₃ is selected from the group consisting of hydrogen, lower alkyl, lower alkoxy, aryl, heteroaryl, arylalkyl, heteroarylalkyl, amino, hydroxy, halo, carboxyl, carbalkoyl, cyano, mercapto, alkylthio, arylthio, amido and glycosyloxy; and R₆ is selected from the group consisting of lower alkyl, aryl, arylalkyl and heteroarylalkyl; provided that R₃ is not /3-D-glycosyloxy or hydroxy when R_1; R₂ and R_s are hydrogen, R₄ is methoxy and R₆ is methyl.

15. The method of claim 14, wherein R₃ is glycosyloxy.

16. The method of claim 14, wherein said compound has the structure:

wherein R₇ is selected independently from the group consisting of hydrogen, lower alkyl, lower alkoxy, aryl, heteroaryl, arylalkyl, heteroarylalkyl, amino, hydroxy, halo, carboxyl, carbalkoyl, cyano, mercapto, alkylthio, arylthio, amido and glycosyloxy; R₈ is selected from the group consisting of hydrogen, lower alkyl, lower alkoxy, aryl, heteroaryl, arylalkyl, heteroarylalkyl, amino, hydroxy, halo, carboxyl, carbalkoyl, cyano, mercapto, alkylthio, arylthio and amido; and R₉ is selected from the group consisting of lower alkyl, aryl, arylalkyl and heteroarylalkyl.

17. The method of claim 16, wherein R₉ is methyl.

18. The method of claim 17, wherein said compound has the structure:

19. The method of claim 18, wherein said compound has the structure:

20. The method of claim 15, wherein said compound has the structure:

wherein R₁₂ is selected from the group consisting of hydrogen, lower alkyl, lower alkoxy, aryl, heteroaryl, arylalkyl, heteroarylalkyl, amino, hydroxy, halo, carboxyl, carbalkoyl, cyano, mercapto, alkylthio, arylthio, amido and glycosyloxy; R₁₃ and R₁₄ are selected independently from the group consisting of hydrogen, lower alkyl, lower alkoxy, aryl, heteroaryl, arylalkyl, heteroarylalkyl, amino, hydroxy, halo, carboxyl, carbalkoyl, cyano, mercapto, alkylthio, arylthio and amido; and R₁₅ is selected from the group consisting of lower alkyl, aryl, arylalkyl and heteroarylalkyl; provided, however, that R₁₂ is not /3-D-glycosyloxy or hydroxy when R₁₄ is hydrogen, R₁₃ is methoxy and R₁₅ is methyl.

21. The method of claim 20, wherein R₁₅ is methyl,

22. The method of claim 21, wherein said compound has the structure:

23. The method of claim 14, wherein said compound has the structure:

wherein R_ιe, R₁₈ and R₁₉ are selected independently from the group consisting of hydrogen, lower alkyl, lower alkoxy, aryl, heteroaryl, arylalkyl, heteroarylalkyl, amino, hydroxy, halo, carboxyl, carbalkoyl, cyano, mercapto, alkylthio, arylthio and amido; R₁₇ is selected from the group consisting of hydrogen, lower alkyl, lower alkoxy, aryl, heteroaryl, arylalkyl, heteroarylalkyl, amino, hydroxy, halo, carboxyl, carbalkoyl, cyano, mercapto, alkylthio, arylthio, amido and glycosyloxy; and R₂₀ is selected from the group consisting of lower alkyl, aryl, arylalkyl and heteroarylalkyl; provided, however, that R₁₇ is not /3-D-glycosyloxy or hydroxy when R₁₆ and R₁₉ are hydrogen, R₁₈ is methoxy and R₂₀ is methyl.

24. The method of claim ^*23, wherein R₂₀ is methyl.

25. The method of claim 24, wherein said compound has the structure:

26. The method of claim 24, wherein said compound has the structure:

27. The method of claim 14, wherein said condition is selected from the group consisting of inflammatory bowel disease, rheumatoid arthritis, burn injury, inflammatory side effects of irradiation, inflammatory side effects of chemotherapy, osteomyelitis, granulomatous disease, hepatitis, pancreatitis, lupus erythematosus, reperfusion injury from heart attack or stroke and autoimmune dermatitis.

28. The method of claim 27, wherein said condition is rheumatoid arthritis.

29. The method of claim 27, wherein said condition is reperfusion injury from heart attack or stroke.

30. The method of claim 27, wherein said condition is inflammatory bowel disease.

31. A method for treating asthma in an animal, comprising administering to such animal an effective amount of a compound having the structure:

and its pharmaceutically acceptable salts, wherein R_lf R₂, R₄ and R₅ are selected independently from the group consisting of hydrogen, lower alkyl, lower alkoxy, aryl, heteroaryl, arylalkyl, heteroarylalkyl, amino, hydroxy, halo, carboxyl, carbalkoyl, cyano, mercapto, alkylthio, arylthio and amido; R₃ is selected from the group consisting of hydrogen, lower alkyl, lower alkoxy, aryl, heteroaryl, arylalkyl, heteroarylalkyl, amino, hydroxy, halo, carboxyl, carbalkoyl, cyano, mercapto, alkylthio, arylthio, amido and glycosyloxy; and R₆ is selected from the group consisting of lower alkyl, aryl, arylalkyl and heteroarylalkyl; provided that R₃ is not α-L- or /3-D- glycosyloxy or hydroxy when R-, R₂, R₄ and R₅ are hydrogen, halogen, or lower alkoxy and R₆ is lower alkyl.

32. A compound, comprising the structure!

wherein R₁₀ is selected from the group consisting of hydroxy, halo, lower alkoxy, mercapto, lower alkylthio, aryloxy and heteroaryloxy; and R₁₁ is selected from the group consisting of lower alkyl, aryl, heteroaryl, arylalkyl and heteroarylalkyl.

33. The compound of claim 32, having the structure:

34. A composition for the treatment of chronic inflammatory conditions, comprising the compound of claim 1 in a pharmaceutically acceptable carrier.

35. The composition of claim 34, wherein said compound is the compound of claim 32

36. The composition of claim 34, wherein said compound is the compound of claim 33.