WO2012081038A2

WO2012081038A2 - Anticancer compounds and targeting cancer with the same

Info

Publication number: WO2012081038A2
Application number: PCT/IN2011/000865
Authority: WO
Inventors: Martin Annette; Shruti Patil; Nilesh Shridhar Malik; Kailash Dattatraya Panghavane
Original assignee: Godavari Biorefineries Limited
Priority date: 2010-12-17
Filing date: 2011-12-16
Publication date: 2012-06-21
Also published as: WO2012081038A3

Abstract

The present invention provides compounds having the general formula I or pharmaceutically acceptable salt thereof, and pharmaceutically acceptable compositions having ability to inhibit proliferation of and/or eradicate cancer cells and/or cancer cells having significant self-renewal potential, such as cancer stem cells (CSCs). Such compounds have the general formula I. The invention also provides the use of a compound of formula I, or a pharmaceutically acceptable salt thereof, or pharmaceutically acceptable compositions thereof in inhibiting the proliferation of and/or eradicating cancer cells and/or cancer cells having significant self-renewal potential, such as cancer stem cells (CSCs).

Description

Title:

Anticancer compounds and targeting cancer with the same

Field of Invention The present invention relates to anticancer compounds. More particularly the present invention relates to the use of anticancer compounds in targeting cancer.

Background of the Invention Cancer refers collectively to a family of diseases that start mainly from the uncontrolled proliferation of cells, invading neighboring normal tissues or organs which establishes a new growth place therein that can eventually cause death.

The three most common types of cancer treatment chemotherapy, surgery and radiotherapy are aimed at removing the cancer cells or destroying them in the body by surgery, with medicines or other active agents.

Surgery cannot be an option for all types of cancers, it may not be possible if the cancer has spread to other areas of the body besides tumor or if the tumor cannot be removed without damaging vital organs, such as the liver or brain. Radiotherapy uses radiation to damage cancer cells so that they can't multiply. However, such radiations are known to be harmful and may not be always effective. Besides, radiotherapy may not be the only treatment needed.

A combination of surgery and radiotherapy may be used for localized tumors but is ineffective where cancer has spread. Also, surgery and chemotherapy have their own risks and side effects hence combination of radiotherapy with them is not an option for all suffering from cancer.

In chemotherapy, anticancer agents are not effective in the treatment of general epithelial-derived tumors, such as breast, colon and lung cancer. This is mainly due to the resistance of cancer cells to several anti-cancer agents, leading to very limited application of the anti-cancer agents.

In recent years, despite conspicuous advances the incidence of cancer and mortality keeps increasing.

Most primary tumors display a notable degree of cellular heterogeneity. Within the tumor there are cancer stem cells a very rare population of cells with the capacity for limitless self-renewal and to cause the heterogeneous lineages of cancer cells that comprise the tumor. CSCs may generate tumors through the stem cell processes of self-renewal and differentiation into multiple cell types. Such cells are proposed to persist in tumors as a distinct population and cause relapse and metastasis by giving rise to new tumors. Normal somatic stem cells are naturally resistant to chemotherapeutic agents. CSCs that have mutated from normal stem cells may also express proteins that would increase their resistance towards chemotherapeutic agents. These surviving CSCs then repopu!ate the tumor, causing relapse of a more drug-resistant cancer.

Although modern chemotherapies kill a majority of the cells in a tumor, evidence clearly indicates that cancer stems cells often remain. This concept may explain why it is possible to treat many cancers until the tumor can no longer be detected and yet the cancer returns.

Therefore, development of specific therapies targeted at CSCs holds hope for improvement of survival and quality of life of cancer patients, especially for sufferers of drug-resistant tumors or metastatic disease. Thus, there is a need in the art also for agents, the use of which can inhibit, reduce, and/or eliminate cancer stem cells, the root cause of cancer.

Summary of the Invention

Accordingly, compounds of this invention have been identified which show capability for inhibition of proliferation of and/or eradication of cancer cells and/or cancer cells having significant self-renewal potential, such as cancer stem cells (CSCs) thus offering a new opportunity for the treatment of cancers.

In some of the embodiments the present invention provides compounds having the general formula I or pharmaceutically acceptable salt thereof, and pharmaceutically acceptable compositions having ability to inhibit proliferation of and/or eradicate cancer cells and/or cancer cells having significant self- renewal potential, such as cancer stem cells (CSCs). Such compounds have the general formula I:

( R% I In some embodiments the invention provides the use of a compound of formula I, or a pharmaceutically acceptable salt thereof, to prepare a medicament useful in targeting cancer cells and/or cancer cells having significant self-renewal potential, such as cancer stem cells for treating a variety of diseases, disorders or condition. Such diseases, disorders, or conditions include those described herein.

In some embodiments the invention provides composition comprising a compound of formula I, or a pharmaceutically acceptable salt thereof, for inhibiting the proliferation of and/or eradicating cancer cells and/or cancer cells having significant self-renewal potential, such as cancer stem cells (CSCs). In some embodiments the invention provides the use of a compound of formula I, or a pharmaceutically acceptable salt thereof, or pharmaceutically acceptable compositions thereof in inhibiting the proliferation of and/or eradicating cancer cells and/or cancer cells having significant self-renewal potential, such as cancer stem cells (CSCs).

In some other embodiments the invention provides a compound of formula I, or a pharmaceutically acceptable salts thereof or pharmaceutically acceptable compositions thereof for the prophylactic or therapeutic treatment of cancer.

In some other embodiments the invention provides a method of inhibiting proliferation of or eradication of cancer cells and/or cancer cells having significant self-renewal potential, such as cancer stem cells in a patient comprising the step of administering to patient a compound of formula I, or a pharmaceutically acceptable salts thereof or pharmaceutically acceptable compositions thereof.

Description of the Invention

Accordingly, the present invention is directed towards compounds represented by Formula 1 and pharmaceutically acceptable compositions thereof. The present invention relates to the use of such anticancer compounds represented by Formula 1 in targeting cancer. The present invention also relates to the use of anticancer compounds represented by Formula 1 and pharmaceutically acceptable compositions thereof, for inhibition of proliferation of and/or eradication of cancer cells and/or cancer cells having significant self-renewal potential, such as cancer stem cells. Further, the present invention relates to the use of anticancer compounds represented by Formula 1 for prevention and/or treatment of cancer. In certain embodiments, the present invention provides compounds for targeting cancer by inhibition or proliferation and/or eradication of cancer cells and/or cancer cells having significant self-renewal potential, such as cancer stem cells.

In some embodiments, such compounds include those having formula I:

I

or a pharmaceutically acceptable salt thereof, wherein:

each of Ring B and Ring C is independently a 4-8 membered partially unsaturated, or aromatic ring having 0-3 heteroatoms independently selected from nitrogen, oxygen, or sulfur;

n is 0-4;

m is 0-3;

p is 0-2; each R³, R⁴ and R⁵ is independently halogen, -CN, -N02, -R, -OR, -SR, -N(R)₂, - N(R)C(0)R, C(0)RN(R)₂, -N(R)C(0)N(R)₂, -N(R)C(0)OR, -OC(0)N(R), -N(R)S0₂R, - S02RN(R)₂, C(0)R, -C(0)OR, -OC(0)R, -C(0)OR, -S(0)R, or -S0₂R;

each R is independently hydrogen or an alkyl, optionally substituted group selected from Cl-6 aliphatic, alkenyl, alkynyl, a 3-8 membered saturated or partially unsaturated monocyclic carbocyclic ring, aryl, phenyl, an 8-10 membered bicyclic aromatic carbocyclic ring; a 4-8 membered saturated or partially unsaturated monocyclic heterocyclic ring having 1-2 heteroatoms independently selected from nitrogen, oxygen, or sulfur, a 5-6 membered monocyclic heteroaromatic ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur, or an 8-10 membered bicyclic heteroaromatic ring having 1-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur;

each of R2 and R2' is independently hydrogen or an optionally substituted Cl-6 aliphatic, or:

R2 and R2' are taken together to form =0 or =S;

Q is -O-, -S-, or -N(R)-;

A is O or S;

R¹ is independently -OH, OR, -OC(0)R, or a protected hydroxyl group.

Compounds of this invention include those described generally above, and further described herein below.

In certain embodiments, Ring B is a 5-6 membered partially unsaturated, or aromatic ring having 0-3 heteroatoms independently selected from nitrogen, oxygen, or sulfur. In some embodiments, Ring B is a 5-6 membered aromatic ring having 1-3 heteroatoms independently selected from nitrogen, oxygen, or sulfur. In some embodiments, Ring B is pyrido or thiopheno. In some embodiments, Ring B is benzo. As defined generally above, Ring C is a 4-8 membered partially unsaturated or aromatic ring having 0-3 heteroatoms independently selected from nitrogen, oxygen, or sulfur.

In some embodiments, Ring C is a 5-6 membered partially unsaturated or aromatic ring having 1-2 heteroatoms independently selected from nitrogen or oxygen. In some embodiments, Ring C is a 5 membered partially unsaturated or aromatic ring having 2 heteroatoms selected from nitrogen, oxygen or sulfur. In some embodiments, Ring C is 1,3-dioxolano.

As defined generally above, n is 0-4. In certain embodiments, n is 1-3. In some embodiments, n is 2. In some embodiments, n is 0. As defined generally above, m is 0-3. In certain embodiments, m is 1-2. In some embodiments, m is 0.

As defined generally above, p is 0-2. In certain embodiments, p is 0. In some embodiments, p is 2.

As defined generally above, each R³, R⁴ and R⁵ is independently halogen, -CN, - N02, -R, -OR, -SR, -N(R)₂, -N(R)C(0)R, C(0)RN(R)₂, -N(R)C(0)N(R)₂, -N(R)C(0)OR, - OC(0)N(R), -N(R)S0₂R, -S02RN(R)₂, C(0)R, -C(0)OR, -OC(0)R, -C(0)OR, -S(0)R, or -S0₂R. In certain embodiments, each R³, R⁴ and R⁵ is independently halogen, CN, OR, SR, or OC(0)R. In some embodiments, each R³ is independently halogen, OR, or -OC(0)R. In some embodiments each R³ is -OR. In some embodiments, each R⁴ is independently halogen or -OR. In some embodiments, each R⁵ is independently halogen, C(0)OR, or -R. In some embodiments, each R⁵ is halogen. In some embodiments, each R⁵ is -R. In some embodiments, each R³, R⁴ and R⁵ is hydrogen.

In certain embodiments, each R is independently hydrogen or an optionally substituted group selected from Ci.6 aliphatic, phenyl, or a 5-6 membered monocyclic heteroaromatic ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur. In some embodiments, each R is independently hydrogen or an optionally substituted Ci-6 aliphatic group. In some embodiments, each R is independently hydrogen or an optionally substituted Ci.₂ aliphatic group. In some embodiments, each R is hydrogen. In some embodiments, each R is an optionally substituted Ci_-2 aliphatic group.

As defined generally above, each of R² and R² is independently hydrogen or an optionally substituted Ci_-6 aliphatic, or: R² and R² are taken together to form =0 or =S. As defined generally above, Q is -0-, -S-, or -N(R)-. In certain embodiments, Q is -0-, or-N(R)-. In some embodiments Q is -0-. In some embodiments, Q is -N(R)-. As defined generally above, A is 0 or S. In certain embodiments, A is 0. In some embodiments A is S.

As defined generally above, ¹ is-OH, -OR, -OC(0)R, or a protected hydroxyl group. In certain embodiments, R¹ is independently -OH, -OR, or -0C(0)R. In some embodiments, R¹ is -OH. In some embodiments, R¹ is OR. In some embodiments, R¹ is OC(0)R. In some embodiments, R¹ is a protected hydroxyl group. Hydroxyl protecting groups are well known in the art.

In certain embodiments, the compounds of the present invention are in the form pharmaceutically acceptable derivative including but not limited to any non-toxic salt, ester, salt of an ester or other derivative of a compound of this invention that, upon administration to a recipient, is capable of providing, either directly or indirectly, a compound of this invention or an inhibitorily active metabolite or residue thereof.

In certain embodiments, the compounds of the present invention are in the form of pharmaceutically acceptable salts. Such salts are acid or base salts.

Examples of pharmaceutically acceptable acid salts are organic acid addition salts formed with acids which form a physiological acceptable anion, for example, tosylate, methanesulfonate, acetate, citrate, malonate, tartrate, succinate, benzoate, ascorbate, α-ketoglutarate, and a- glycerophosphate. Suitable inorganic salts may also be formed, including hydrochloride, sulfate, nitrate, bicarbonate, and carbonate salts. Other pharmaceutically acceptable salts include adipate, alginate, aspartate, benzenesulfonate, bisulfate, borate, butyrate, camphorate, camphorsulfonate, citrate, cyclopentanepropionate, digluconate, dodecylsulfate, ethanesulfonate, formate, fumarate, glucoheptonate, gluconate, hemisulfate, heptanoate, hexanoate, hydroiodide, 2- hydroxy-ethanesulfonate, lactobionate, lactate, laurate, lauryl sulfate, malate, maleate, malonate, 2-naphthalenesulfonate, nicotinate, nitrate, oleate, oxalate, palmitate, pamoate, pectinate, persulfate, 3-phenylpropionate, phosphate, pivalate, propionate, stearate, succinate, sulfate, tartrate, thiocyanate, p- toluenesulfonate, undecanoate, valerate salts, and the like.

Salts derived from appropriate bases include alkali metal, alkaline earth metal, ammonium and

salts. Representative alkali or alkaline earth metal salts include sodium, lithium, potassium, calcium, magnesium, and the like. Further pharmaceutically acceptable salts include, when appropriate, nontoxic ammonium, quaternary ammonium, and amine cations formed using counterions such as halide, hydroxide, carboxylate, sulfate, phosphate, nitrate, loweralkyl sulfonate and aryl sulfonate.

Pharmaceutically acceptable salts may be obtained using standard procedures well known in the art, for example by reacting sufficiently basic compound such as an amine with a suitable acid affording a physiologically acceptable anion. Alkali metal (for example, sodium, potassium or lithium) or alkaline earth metal (for example calcium) salts of carboxylic acids can also be made.

It will be appreciated by those skilled in the art that compounds as represented by Formula 1 exhibit polymorphism. It is to be understood that the present invention encompasses, polymorphic forms, of a compounds represented by Formula 1, which possess the useful properties described herein.

Unless otherwise stated, structures depicted herein are also meant to include all isomeric (e.g., enantiomeric, diastereomeric, and geometric (or conformational)) forms of the structure; for example, the R and S configurations for each asymmetric center, Z and E double bond isomers, and Z and E conformational isomers. Therefore, single stereochemical isomers as well as enantiomeric, diastereomeric, and geometric (or conformational) mixtures of the present compounds are within the scope of the invention. Unless otherwise stated, all tautomeric forms of the compounds of the invention are within the scope of the invention. Additionally, unless otherwise stated, structures depicted herein are also meant to include compounds that differ only in the presence of one or more isotopically enriched atoms. For example, compounds having the present structures including the replacement of hydrogen by deuterium or tritium, or the replacement of a carbon by a ¹³C- or ¹⁴C-enriched carbon are within the scope of this invention. Such compounds are useful, for example, as analytical tools, as probes in biological assays, or as therapeutic agents in accordance with the present invention. In certain embodiments, a warhead moiety, R¹, of a provided compound comprises one or more deuterium atoms. In certain embodiments, the present invention provides a compound of formula II:

II

or a pharmaceutically acceptable salt thereof, wherein each variable is defined above and in classes and subclasses described above and herein for compounds of formula I.

In certain embodiments, the present invention provides a compound of formula

III:

III or a pharmaceutically acceptable salt thereof, wherein each variable is defined above and in classes and subclasses described above and herein for compounds of formula I.

In certain embodiments, the present invention provides a compound of formula IV:

IV

or a pharmaceutically acceptable salt thereof, wherein each variable is defined above except R³ which is the same as R³ and in classes and subclasses described above and herein for compounds of formula I. Exemplary compounds of present invention are set forth herein, below:

Exemplary Compounds of Formula I

1-1 1-2

1-3

1-5 1-6

In certain embodiments, the present invention provides any compound selected from those depicted above, or a pharmaceutically acceptable salt.

In certain other embodiments the invention provides the use of a compound of formula I, or a pharmaceutically acceptable salt thereof, to prepare a medicament useful for inhibiting proliferation and/or eradication of cancer cells and/or cancer cells having significant self-renewal potential, such as cancer stem cells for treating cancer in an animal. The present invention further provides pharmaceutical compositions comprising the compounds represented by the Formula 1 for inhibition and/or eradication of cancer cells and/or cancer cells having significant self-renewal potential, such as cancer stem cells for prevention and/or treatment of cancer. According to certain embodiment, the invention provides a composition comprising a compound of this invention or a pharmaceutically acceptable derivative thereof and a pharmaceutically acceptable carrier, adjuvant, or vehicle.

In certain embodiments, the amount of compound in compositions of this invention is such that is effective to inhibit cancer cells and/or cancer cells having - significant self-renewal potential, such as cancer stem cells in a biological sample or in a patient. The exact amount required will vary from subject to subject, depending on the species, age, and general condition of the subject, the severity of the infection, the particular agent, its mode of administration, and the like. The compounds of the invention or a pharmaceutically acceptable salt or pharmaceutical compositions thereof, can be formulated in a variety of forms adapted to the chosen route of administration and uniformity of dosage for administration to a subject in the need thereof for example human or animal. For example the type of formulations into which the compounds of the invention or a pharmaceutically acceptable salt or pharmaceutical compositions thereof, can be formulated include oral, rectal, parenteral, intracisternal, intravaginal, intraperitoneal, topical, bucal, nasal or any other type of formulation depending on the severity of the infection being treated. In certain embodiments, formulation is an oral formulationin the form of solid dosage forms selected from but not limiting to capsules, tablets, pills, powders, and granules. In such solid dosage forms, the active compound is mixed with at least one inert, pharmaceutically acceptable excipient or carrier such as fillers or extenders, binders, humectants, disintegrating agents, retarding agents, absorption accelerators, wetting agents, absorbents, lubricants, buffering agents, electrolytes, sweetening agent, flavoring agent or other suitable agent to render the appropriate properties to the desired dosage forms. Exemplary inert, pharmaceutically acceptable excipient or carrier or vehicles or adjuvants include sodium citrate or dicalcium phosphate, starches, lactose, sucrose, glucose, mannitol, and silicic acid, cellulose-based substances, carboxymethylcellulose, alginates, gelatin, polyvinylpyrrolidinone, sucrose, acacia gum, zinc salts, colloidal silica, magnesium trisilicate, polyethylene glycol, sodium carboxymethylcellulose, polyacrylates, waxes, polyethylene-polyoxypropylene-block polymers, wool fat, paraffin, glycerol agar-agar, calcium carbonate, alginic acid, sodium carbonate, quaternary ammonium compounds, cetyl alcohol, glycerol monostearate, kaolin, bentonite clay, talc, calcium stearate, magnesium stearate, sodium lauryl sulfate, ion exchangers, alumina, aluminum stearate, lecithin, serum proteins such as human serum albumin, phosphates, glycine, sorbic acid, potassium sorbate, partial glyceride mixtures of saturated vegetable fatty acids, salts, protamine sulfate, disodium hydrogen phosphate, potassium hydrogen phosphate, sodium chloride, peppermint, oil of wintergreen, or cherry or other flavoring agent, water, and/or mixtures thereof. Various other materials may be present as coatings or to otherwise modify the physical form of the solid unit dosage form. For instance, tablets, pills, or capsules may be coated with gelatin, wax, shellac or sugar and the like. The formulation can be also be formulated to release the active ingredient(s) only, or preferentially, in a certain part of the intestinal tract, optionally, in a delayed manner. Liquid dosage forms for oral administration include, but are not limited to, pharmaceutically acceptable emulsions, microemulsions, solutions, suspensions, syrups and elixirs. In addition to the active compounds, the liquid dosage forms may contain inert diluents commonly used in the art such as, for example, water or other solvents, solubilizing agents and emulsifiers such as ethyl alcohol, isopropyl alcohol, ethyl carbonate, ethyl acetate, benzyl alcohol, benzyl benzoate, propylene glycol, 1,3-butylene glycol, dimethylformamide, oils (in particular, cottonseed, groundnut, corn, germ, olive, castor, and sesame oils), glycerol, tetrahydrofurfuryl alcohol, polyethylene glycols and fatty acid esters of sorbitan, and mixtures thereof. Besides inert diluents, the oral compositions can also include adjuvants such as wetting agents, suspending agents, sweetening, flavoring or perfuming agents and/or preservatives.

The intravenous or intraperitoneal formulations include injection or infusion. The pharmaceutical dosage forms suitable for injection or infusion can include sterile aqueous solutions or dispersions or sterile powders comprising the active ingredient which are adapted for the extemporaneous preparation of sterile injectable or infusible solutions or dispersions, optionally encapsulated in liposomes. In all cases, the ultimate dosage form should be sterile, fluid and stable under the conditions of manufacture and storage. The liquid carrier or vehicle can be a solvent or liquid dispersion medium comprising, for example, water, ethanol, a polyol (for example, glycerol, propylene glycol, liquid polyethylene glycols, and the like), vegetable oils, nontoxic glyceryl esters, and suitable mixtures thereof. The proper fluidity can be maintained, for example by the formation of liposomes, by the maintenance of the required particle size in the case of dispersions or by the use of surfactants. The prevention of the action of microorganisms can be brought about by various antibacterial and antifungal agents, for example, parabens, chlorobutanol, phenol, sorbic acid, thimerosal, and the like. In many cases, it will be preferable to include isotonic agents, for example, sugars, buffers or sodium chloride. Sterile injectable solutions are prepared by incorporating the compounds represented by the Formula 1 in the required amount in the appropriate solvent with various of the other ingredients enumerated above, as required, followed by filter sterilization. In the case of sterile powders for the preparation of sterile injectable solutions, the preferred methods of preparation are vacuum drying and the freeze drying techniques, which yield a powder of the active ingredient plus any additional desired ingredient present in the previously sterile-filtered solutions.

Injectable compositions can also include agents delaying absorption, for example, aluminum monostearate and gelatin. Alternatively, delayed absorption of a parenterally administered compound form is accomplished by dissolving or suspending the compound in an oil vehicle. Injectable depot forms are made by forming microencapsule matrices of the compound in biodegradable polymers such as polylactide-polyglycolide, poly(orthoesters) or poly(anhydrides). Depot injectable formulations are also prepared by entrapping the compound in , liposomes or microemulsions that are compatible with body tissues.

For topical administration, the compounds represented by the Formula 1 may be applied in pure form, i.e., when they are liquids. Alternately, topical formulation may also be prepared comprising the compounds of the invention or pharmaceutical acceptable salt thereof, in combination with a dermatologically acceptable carrier, which may be a solid or a liquid. Useful solid carriers include finely divided solids such as talc, clay, microcrystalline cellulose, silica, alumina and the like. Useful liquid carriers include water, alcohols or glycols or water- alcohol/glycol blends, in which the present compounds can be dissolved or dispersed at effective levels, optionally with the aid of non-toxic surfactants. Adjuvants such as fragrances and additional antimicrobial agents can be added to optimize the properties for a given use. The resultant liquid compositions can be applied from absorbent pads, used to impregnate bandages and other dressings, or sprayed onto the affected area using pump-type or aerosol sprayers. Thickeners such as synthetic polymers, fatty acids, fatty acid salts and esters, fatty alcohols, modified celluloses or modified mineral materials can also be employed with liquid carriers to form spreadable pastes, gels, ointments, soaps, and the like, for application directly to the skin of the user. Dosage forms for topical or transdermal administration of a compound of this invention include ointments, pastes, creams, lotions, gels, powders, solutions, sprays, inhalants or patches. The active component is admixed under sterile conditions with a pharmaceutically acceptable carrier and any needed preservatives or buffers as may be required.

Ophthalmic formulation, ear drops, and eye drops are also contemplated as being within the scope of this invention. Ophthalmic formulations may be formulated as micronized suspensions in isotonic, pH adjusted sterile saline, or, preferably, as solutions in isotonic, pH adjusted sterile saline, either with or without a preservative such as benzylalkonium chloride. Alternatively, for ophthalmic uses, the pharmaceutically acceptable compositions may be formulated in an ointment such as petrolatum. Additionally, the present invention contemplates the use of transdermal patches, which have the added advantage of providing controlled delivery of a compound to the body. Such dosage forms can be made by dissolving or dispensing the compound in the proper medium. Absorption enhancers can also be used to increase the flux of the compound across the skin. The rate can be controlled by either providing a rate controlling membrane or by dispersing the compound in a polymer matrix or gel.

Formulation for rectal or vaginal administration are preferably suppositories which can be prepared by mixing the compounds of this invention with suitable non-irritating excipients or carriers such as cocoa butter, polyethylene glycol or a suppository wax which are solid at ambient temperature but liquid at body temperature and therefore melt in the rectum or vaginal cavity and release the active compound. Pharmaceutically acceptable compositions of this invention may also be formulated for nasal administration through aerosol or inhalation. Such compositions are prepared according to techniques well-known in the art of pharmaceutical formulation and may be prepared as solutions in saline, employing benzyl alcohol or other suitable preservatives, absorption promoters to enhance bioavailability, fluorocarbons, and/or other conventional solubilizing or dispersing agents.

Most preferably, pharmaceutically acceptable compositions of this invention are formulated for oral administration. Such formulations may be administered with or without food.

The amount of compounds of the present invention that may be combined with the carrier materials to produce a composition in a single dosage form will vary depending upon the host treated, the particular mode of administration.

It should also be understood that a specific dosage and treatment regimen for any particular patient will depend upon a variety of factors, including the activity of the specific compound employed, the age, body weight, general health, sex, diet, time of administration, rate of excretion, drug combination, and the judgment of the treating physician and the severity of the particular disease being treated. The amount of a compound of the present invention in the composition will also depend upon the particular compound in the composition.

Compounds and compositions described herein are generally useful for the inhibition of proliferation and/or eradication of cancer cells and/or cancer cells having significant self-renewal potential, such as cancer stem cells. Thus, provided compounds are useful for prevention and/or treatment of cancers, including, but not limited to hematological cancers and solid tumors.

The invention in one embodiment relates to the use of compounds represented by the Formula 1 for inhibition of proliferation of and/or eradication of cancer cells and/or cancer cells having significant self-renewal potential, such as cancer stem cells.

The use of compounds represented by the Formula 1 for inhibition and/or eradication of cancer cells and/or cancer cells having significant self-renewal potential, such as cancer stem cells include such cells within tumors or leukemic cells.

Another embodiment of the present invention relates to a method of inhibiting cancer cells and/or cancer cells having significant self-renewal potential, such as cancer stem cells in a patient comprising the step of administering to said patient a compound of the present invention, or a composition comprising said compound.

According to certain embodiments, the invention relates to a method of inhibiting cancer cells and/or cancer cells having significant self-renewal potential, such as cancer stem cells in a patient, leading to remission of the cancer, comprising the step of administering to said patient a compound of the present invention, or a composition comprising said compound. In some embodiments the present invention provides a method for treating a disorder mediated by cancer cells and/or cancer cells having significant self- renewal potential, such as cancer stem cells, in a patient in need thereof, comprising the step of administering to said patient a compound according to the present invention or pharmaceutically acceptable composition thereof. Such disorders are described in detail herein.

According to another embodiment, the invention relates to a method of inhibiting proliferation of cancer cells and/or cancer cells having significant self- renewal potential, such as cancer stem cells, in a biological sample comprising the step of contacting said biological sample with a compound of this invention, or a composition comprising said compound. In certain embodiments, the invention relates to a method of killing cancer cells and/or cancer cells having significant self-renewal potential, such as cancer stem cells in a biological sample comprising the step of contacting said biological sample with a compound of this invention, or a composition comprising said compound.

Inhibition of cancer cells and/or cancer cells having significant self-renewal potential, such as cancer stem cells in a biological sample is useful for a variety of purposes that are known to one of skill in the art. Examples of such purposes include, but are not limited to biological assays, gene expression studies, and biological target identification.

Examples of tissues containing cancerous cells whose proliferation is inhibited by the compounds and compositions described herein or against which the methods described herein are useful or types of cancer for the treatment of which compounds and compositions of the present invention may be used include but are not limited to ovary, breast, prostate, brain, blood, bone marrow, liver, pancreas, skin, kidney, colon, lung, testicle, penis, thyroid, parathyroid, pituitary, thymus, retina, uvea, conjunctiva, spleen, head, neck, trachea, gall bladder, rectum, salivary gland, adrenal gland, throat, esophagus, lymph nodes, sweat glands, sebaceous glands, muscle, heart, and stomach.

Examples of cancer cell lines that are inhibited by the compounds and compositions described herein and against which the methods described herein are useful include, breast, prostrate and ovarian cell lines. Some of the breast, prostrate and ovarian cell lines selected include but not limited to DU145, PC3, LNCaP, MDA MB 231, MCF7, T47D, MCF10A, HeLa, or L929.

Examples of cancer cell lines that are subject to the cytotoxic effects of the compounds and compositions described herein or exhibit apoptotic effects following treatment with the compounds and compositions described herein or against which the methods described herein are useful include breast, prostrate and ovarian cell lines. Some of the breast, prostrate and ovarian cell lines selected include but are not limited to DU145, PC3, LNCaP, MDA MB 231, MCF7, T47D, MCF10A, HeLa, or L929.

The activity of a compound utilized in this invention as an inhibitor of cancer cells and/or cancer cells having significant self-renewal potential, such as cancer stem cells, may be assayed in vitro or in vivo. An in vivo assessment of the inhibitory or cytotoxic activity of the compounds of the invention may be made using an animal model of cancer, e.g., a rodent or primate model. Cell-based assays may be performed using, e.g., a cell line isolated from a tumor or blood-borne cancer. Cell-based assays for activity against a specific protein or nucleic acid component of a cancer cell line, e.g., an enzyme, structural protein, DNA or RNA, may also be performed. Additionally, biochemical or mechanism-based assays, e.g., transcription assays using a purified protein, Northern blot, RT-PCR, etc., may be performed. In vitro assays include assays that determine cell morphology, viability, cell count, or growth inhibition, and/or the cytotoxicity, enzyme inhibitory activity, and/or the subsequent functional consequences of treatment of cancer cells with compounds of the invention. Alternate in vitro assays quantitate the ability of the inhibitor to bind to protein or nucleic acid molecules within the cell. Inhibitor binding may be measured by radiolabelling the inhibitor prior to binding, isolating the inhibitor/target molecule complex and determining the amount of radiolabel bound. Alternatively, inhibitor binding may be determined by running a competition experiment where new inhibitors are incubated with purified proteins or nucleic acids bound to known radioligands. Detailed conditions for assaying a compound utilized in this invention as an inhibitor of cancer cells or CSCs, are set forth in the Examples below. The aforementioned assays are exemplary and not intended to limit the scope of the invention. The skilled practitioner can appreciate that modifications can be made to conventional assays to develop equivalent assays that obtain the same result.

Depending upon the particular condition, or disease, to be treated, additional therapeutic agents, which are normally administered to treat that condition, may be administered in combination with compounds and compositions of this invention. The compounds represented by the Formula 1 may optionally be used in combination with one or more other anticancer or chemotherapeutic agents or another inhibitor of cancer cells or CSCs or compositions. In certain embodiments, a provided compound, or composition thereof, is administered in combination with such chemotherapeutic agents include, but are not limited to agents such as kinase inhibitors, alkylating agents, anti-metabolites, tubulin stabilizers, tubulin assembly inhibitors, DNA replication inhibitors, cell cycle inhibitors, topoisomerase inhibitors, cytotoxic antibiotics or nanoparticle or protein conjugates of any of the aforementioned agents. In certain embodiments, the chemotherapeutic agents used in combination with compounds or compositions of the invention include, but are not limited to imatinib, nilotinib, gefitinib, sunitinib, carfilzomib, salinosporamide A, retinoic acid, cisplatin, carboplatin, oxaliplatin, mechlorethamine, cyclophosphamide, chlorambucil, ifosfamide, azathioprine, mercaptopurine, doxifluridine, fluorouracil, gemcitabine, methotrexate, tioguanine, vincristine, vinblastine, vinorelbine, vindesine, podophyllotoxin, etoposide, teniposide, tafluposide, paclitaxel, docetaxel, irinotecan, topotecan, amsacrine, actinomycin, doxorubicin, daunorubicin, valrubicin, idarubicin, epirubicin, plicamycin, mitomycin, mitoxantrone, melphalan, busulfan, capecitabine, pemetrexed, epothilones, 13-cis-Retinoic Acid, 2-CdA, 2-Chlorodeoxyadenosine, 5-Azacitidine, 5-Fluorouracil, 5-FU, 6-Mercaptopurine, 6-MP, 6-TG, 6-Thioguanine, Abraxane, Accutane^®, Actinomycin-D, Adriamycin^®, Adrucil^®, Afinitor^®, Agrylin^®, Ala-Cort^®, Aldesleukin, Alemtuzumab, ALIMTA, Alitretinoin, Alkaban-AQ^®, Alkeran^®, All- transretinoic Acid, Alpha interferon, Altretamine, Amethopterin, Amifostine, Aminoglutethimide, Anagrelide, Anandron^®, Anastrozole, Arabinosylcytosine, Ara-C, Aranesp^®, Aredia^®, Arimidex^®, Aromasin^®, Arranon^®, Arsenic Trioxide, Arzerra™, Asparaginase, ATRA, Avastin^®, Azacitidine, BCG, BCNU, Bendamustine, Bevacizumab, Bexarotene, BEXXAR^®, Bicalutamide, BiCNU, Blenoxane^®, Bleomycin, Bortezomib, Busulfan, Busulfex^®, C225, Calcium Leucovorin, Campath^®, Camptosar^®, Camptothecin-11, Capecitabine, Carac™, Carboplatin, Carmustine, Carmustine Wafer, Casodex^® CC-5013, CCI-779, CCNU, CDDP, CeeNU, Cerubidine^® Cetuximab, Chlorambucil, Citrovorum Factor, Cladribine, Cortisone, Cosmegen^® CPT-11, Cytadren^® Cytosar-U^® Cytoxan^® Dacarbazine, Dacogen, Dactinomycin, Darbepoetin Alfa, Dasatinib, Daunomycin, Daunorubicin Hydrochloride, Daunorubicin Liposomal, DaunoXome^® Decadron, Decitabine, Delta-Cortef^® Deltasone^® Denileukin, Diftitox, DepoCyt™, Dexamethasone, Dexamethasone Acetate, Dexamethasone Sodium Phosphate, Dexasone, Dexrazoxane, DHAD, DIC, Diodex, Docetaxel, Doxil^® Doxorubicin, Doxorubicin Liposomal, Droxia™, DTIC, DTIC-Dome^® Duralone^® Efudex^® Eligard™, Ellence™, Eloxatin™, Elspar^® Emcyt^® Epirubicin, Epoetin Alfa, Erbitux, Erlotinib, Erwinia L- asparaginase, Estramustine, Ethyol, Etopophos^®, Etoposide, Etoposide Phosphate, Eulexin^® Evero!imus, Evista^® Exemestane, Fareston^® Faslodex^® Femara^® Filgrastim, Floxuridine, Fludara^® F|udarabine, Fluoroplex^® Fluorouracil, Fluorouracil (cream), Fluoxymesterone, Flutamide, Folinic Acid, FUDR^® Fulvestrant, G-CSF, Gefitinib, Gemcitabine, Gemtuzumab, ozogamicin, ,Gemzar Gleevec™, Gliadel^® Wafer, GM-CSF, Goserelin, Granulocyte - Colony Stimulating Factor, Granulocyte Macrophage Colony Stimulating Factor, Halotestin^® Herceptin® Hexadrol, Hexalen^® Hexamethylmelamine, HMM, Hycamtin^® Hydrea® Hydrocort Acetate^® Hydrocortisone, Hydrocortisone Sodium Phosphate, Hydrocortisone Sodium Succinate, Hydrocortone Phosphate, Hydroxyurea, ibritumomab, Ibritumomab, Tiuxetan, Idamycin^® Idarubicin Ifex^® IFN-alpha, ifosfamide, IL-11, IL-2, Imatinib mesylate, Imidazole Carboxamide, Interferon alfa, Interferon Alfa-2b (PEG Conjugate), lnterleukin-2, lnterleukin-11, Intron A^® (interferon alfa-2b), Iressa^® Irinotecan, Isotretinoin, Ixabepilone, Ixempra™, Kidrolase^®, Lanacort^® Lapatinib, L-asparaginase, LCR, Lenalidomide, Letrozole, Leucovorin, Leukeran, Leukine™, Leuprolide, Leurocristine, Leustatin™, Liposomal Ara-C, Liquid Pred^® Lomustine, L-PAM, L-Sarcolysin, Lupron^® Lupron Depot^® Matulane^® Maxidex, Mechlorethamine, Mechlorethamine Hydrochloride, Medralone^® Medrol^® Megace^® Megestrol, Megestrol Acetate, Melpnalan, Mercaptopurine, Mesna, Mesnex™, Methotrexate, Methotrexate Sodium, Methylprednisolone, Meticorten^® Mitomycin, Mitomycin-C, Mitoxantrone, M- Prednisol^® MTC, MTX, Mustargen^® Mustine, Mutamycin^® Myleran^® Mylocel™, Mylotarg^®, Navelbine^®, Nelarabine, Neosar^®, Neulasta™, Neumega^® Neupogen^® Nexavar^® Nilandron^® Nilotinib, Nilutamide, Nipent^® Nitrogen Mustard, Novaldex® Novantrone^® Nplate, Octreotide, Octreotide acetate, Ofatumumab, Oncospar^® Oncovin^® Ontak^® Onxal™, Oprelvekin, Orapred^® Qrasone^® Oxaliplatin, Paclitaxel, Paclitaxel Protein-bound, Pamidronate, Panitumumab, Panretin^® Paraplatin^® Pazopanib, Pediapred^® PEG Interferon, Pegaspargase, Pegfilgrastim, PEG-INTRON™, PEG-L-asparaginase, PEMETREXED, Pentostatin, Phenylalanine Mustard, Platinol^® Platinol-AQ^® Prednisolone, Prednisone, Prelone^® Procarbazine, PROCRIT^® Proleukin^® Prolifeprospan 20 with Carmustine Implant, Purinethol^® Raloxifene, Revlimid® Rheumatrex^® Rituxan^® Rituximab, Roferon-A® (Interferon Alfa-2a), Romiplostim, Rubex^® Rubidomycin hydrochloride, Sandostatin^® Sandostatin LAR^® Sargramostim, Solu-Cortef^® Solu-Me*drol^® Sorafenib, SPRYCEL™, STI-571, Streptozocin, SU11248, Sunitinib, Sutent^® Tamoxifen, Tarceva^® Targretin^® Tasigna^® Taxol^® Taxotere^® Temodar^® Temozolomide, Temsirolimus, Teniposide, TESPA, Thalidomide, Thalomid^® TheraCys^® Thioguanine, Thioguanine Tabloid^® Thiophosphoamide, Thioplex^® Thiotepa, TICE^® Toposar^® Topotecan, Toremifene, Torisel^® Tositumomab, Trastuzumab, Treanda^® Tretinoin, Trexall™, Trisenox^® TSPA, TYKERB^® VCR, Vectibix™, Velban^® Velcade^® VePesid^® Vesanoid^® Viadur™, Vidaza^® Vinblastine, Vinblastine Sulfate, Vincasar Pfs^® Vincristine, Vinorelbine, Vinorelbine tartrate, VLB, VM-26, Vorinostat, Votrient, VP-16, Vumon^® Xetoda^® Zanosar^® Zevalin™, Zinecard^® Zoiadex^® Zoledronic acid, Zolinza, Zometa^® or combinations of any of the above. In certain embodiments, a combination of 2 or more chemotherapeutic agents may be administered together with compounds of the invention. In certain embodiments, a combination of 3 or more chemotherapeutic agents may be administered with compounds of the invention.

Other examples of agents the inhibitors of this invention may also be combined with include, without limitation: vitamins and nutritional supplements, cancer vaccines, treatments for neutropenia (e.g. G-CSF, filgrastim, lenograstim), treatments for thrombocytopenia (e.g. blood transfusion, erythropoietin), antiemetics (e.g. 5-HT₃ receptor antagonists, dopamine antagonists, NK1 receptor antagonists, histamine receptor antagonists, cannabinoids, benzodiazepines, or anticholinergics), treatments for Alzheimer's Disease such as Aricept* and Excelon^®; treatments for Parkinson's Disease such as L- DOPA/carbidopa, entacapone, ropinrole, pramipexole, bromocriptine, pergolide, trihexephendyl, and amantadine; agents for treating Multiple Sclerosis (MS) such as beta interferon (e.g., Avonex^® and Rebif^®), Copaxone^®, and mitoxantrone; treatments for asthma such as albuterol and Singulair"; agents for treating schizophrenia such as zyprexa, risperdal, seroquel, and haloperidol; antiinflammatory agents such as corticosteroids, TNF blockers, IL-1 RA, azathioprine, cyclophosphamide, and sulfasalazine; immunomodulatory and immunosuppressive agents such as cyclosporin, tacrolimus, rapamycin, mycophenolate mofetil, interferons, corticosteroids, cyclophophamide, azathioprine, and sulfasalazine; neurotrophic factors such as acetylcholinesterase inhibitors, MAO inhibitors, interferons, anti-convulsants, ion channel blockers, riluzole, and anti-Parkinsonian agents; agents for treating cardiovascular disease such as beta-blockers, ACE inhibitors, diuretics, nitrates, calcium channel blockers, and statins; agents for treating liver disease such as corticosteroids, cholestyramine, interferons, and anti-viral agents; agents for treating blood disorders such as corticosteroids, anti-leukemic agents, and growth factors; and agents for treating immunodeficiency disorders such as gamma globulin.

In certain embodiments, compounds of the present invention, or a pharmaceutically acceptable composition thereof, are administered in combination with antisense agents, a monoclonal or polyclonal antibody or an siRNA therapeutic.

The compounds may also be used in combination with other drugs that are used in the treatment/prevention/suppression or amelioration of the diseases or conditions for which compounds as represent by Formula 1 are useful. Such other drugs may be administered, by a route and in an amount commonly used therefor, contemporaneously or sequentially with a compound of the present invention. Those additional agents may be administered separately from an inventive compound-containing composition, as part of a multiple dosage regimen. If administered as part of a multiple dosage regime, the two active agents may be submitted simultaneously, sequentially or within a period of time from one another, normally within five hours from one another. When a compound as per the present invention is used contemporaneously with one or more other drugs, a pharmaceutical composition containing such other drugs in addition to the compound of the present invention is preferred. Accordingly, the pharmaceutical compositions of the present invention include those that also contain one or more other active ingredients, in addition to a compound of the present invention.

The compounds represented by the Formula 1 either alone or in combination with other active or supplementary agents may be used for inhibition of proliferation and/or eradication of cancer cells and/or cancer cells having significant self-renewal potential, such as cancer stem cells for targeting cancer as a standalone therapy or may be used either before or after or in conjunction with other therapies such as radiation, surgery or any other method for prevention and/or treatment of cancer.

The amount of a composition administered will be dependent on the subject being treated, the severity of the affliction, the manner of administration, the judgment of the prescribing physician, etc. The amount of both, an inventive compound and additional therapeutic agent (in those compositions which comprise an additional therapeutic agent as described above) that may be combined with the carrier materials to produce a single dosage form will vary depending upon the host treated and the particular mode of administration. Dosage amount of the compounds represented by the Formula 1, other active agents and interval may be adjusted individually to provide plasma levels of the active species. HPLC assays or bioassays can be used to determine plasma concentrations.

The therapeutically effective dose of molecules is an amount sufficient to cause cell death or inhibit proliferation and cause differentiation of stem cells in solid tumors or leukemias.

The desired dose may conveniently be presented in a single dose or as divided doses administered at appropriate intervals. Preferably, compositions of this invention should be formulated so that a dosage of between 0.01 - 100 mg/kg body weight/day of an inventive can be administered to a patient receiving these compositions. In certain embodiments, the compounds of the invention for oral or parenteral administration may be at dosage levels of about 0.01 mg/kg to about 50 mg/kg and preferably from about 1 mg/kg to about 25 mg/kg, of subject body weight per day, one or more times a day, to obtain the desired therapeutic effect.

In those compositions which comprise an additional therapeutic agent, that additional therapeutic agent and the compound of this invention may act synergistically. Therefore, the amount of additional therapeutic agent in such compositions will be less than that required in a monotherapy utilizing only that therapeutic agent. In such compositions a dosage of between 0.01 - 100 g/kg body weight/day of the additional therapeutic agent can be administered. Resistance to chemotherapeutic drugs is a major factor limiting the efficacy of therapies against many cancers and other proliferative disorders. The rapid division rate of cancer cells allows for the development of mutations or upregulation of pumps such as MDR that afford resistance to current first line chemotherapy drugs. The problem of relapse of cancers in a more drug-resistant form is a critical hurdle faced in effective treatment of cancer patients.

The compounds represented by the Formula 1 or compositions comprising the same for inhibition and/or eradication of cancer cells and/or cancer cells having significant self-renewal potential, such as cancer stem cells provide newer cancer treatment and would reduce the likelihood of clinical relapse after treatment. EXEMPLES

Synthesis: As depicted in the Example below, in certain exemplary embodiments, compounds are prepared according to the following general procedures. It will be appreciated that, although the general methods depict the synthesis of certain compounds of the present invention, the following general methods, and other methods known to one of ordinary skill in the art, can be applied to all compounds and subclasses and species of each of these compounds, as described herein.

Example 1: In certain embodiments, compounds of formula I where ¾ and A are oxygen are prepared according to the procedure outlined in Scheme 1.

Scheme I

In certain embodiments, compounds and synthetic intermediates thereof of the present invention may be prepared according to methods known to one of ordinary skill in the art. Assays:

In certain embodiments, compounds of the present invention are assayed as inhibitors of cancer cells and/or cancer cells having significant self-renewal potential, such as cancer stem cells using methods known in the art including an in vitro cell death assay, an in vitro soft agar growth inhibition assay, an in vitro 3D sphere forming stem cell assay, and in vivo toxicity assays in animals'. Compounds of the present invention were evaluated in a colorimetric in vitro cell death assay as described by Carmichael, J, DeGraff, WG, Gazdar, AF, Minna, JD, and Mitchell, JB. Evaluation of a tetrazolium-based semiautomatic colorimetric assay: assessment of chemosensitivity testing. Cancer Res 1987; 47: 936-942.

Example 2

In- vitro colorimetric cell death assay An exemplary procedure for the in vitro colorimetric cell death assay follows. Cancer cells were plated in a 96 well plate as per predetermined plating efficiency, the plate was incubated for 24 hours in a 5% C0₂ atmosphere at 37 degrees Celsius, a range of concentrations of the compound of the present invention was added to the wells, the plates were incubated further for 48 hours in a 5% C0₂ atmosphere, the plate was centrifuged twice at 3000 rpm for 3 minutes, the supernatant fluid was discarded, 100 uL of 0.5mg/mL MTT solution was added, the plate was incubated for 4 hours in a 5% C0₂ atmosphere at 37 degrees Celsius, the plate was centrifuged twice at 3000 rpm for 3 minutes, supernatant was aspirated very carefully, 200 uL DMSO was added to each well to solubilize MTT crystals and mixed well by shaking the plate, the plate was incubated for 10 minutes in a 5% C02 atmosphere at 37 degrees Celsius, the plate placed on the shaker of an ELISA plate reader and the absorbance at 570 nm was measured, then the percentage of viable cells remaining was calculated by first subtracting the background absorbance then comparing to the absorbance of a non-drug-treated cell sample, and the results were plotted on a graph to determine the IC50 for the compound. The results of the in vitro colorimetric cell death assay are set forth in Table 1.

Table 1. Results of in vitro colorimetric cell death assay.

Example 3

In Vitro 3D Sphere Forming Stem Cell Assay Compounds of the present invention were evaluated in an in vitro 3D sphere forming stem cell assay as described by Rajasekhar, VK, Analytical Methods for Cancer Stem Cells. Methods in Molecular Biology, 2007, Volume 407, 83-95.

An exemplary procedure for the in vitro 3D sphere forming stem cell assay follows. Preparation of Drugs stock and dilutions: Considering the molecular weight of 330.28 g/mol of the compound of formula I- 1, 33 mg was dissolved in ΙΟΟμί. ethyl acetate (tissue culture grade) to attain a final concentration of 1M. To obtain range of concentrations for the experimental study, dilutions were carried out as follows: · 0.01M (10^"2M): 50μί of 10^"1 M solution of compound of formula 1-1 was added to 450μί of ethyl acetate

• 0.001M (10^'3M): 50μί of 10^"2M solution of compound of formula 1-1 was added to 450μΙ. of ethyl acetate

• 0.0001M (10^" M): 50μί. of 10^"3M solution of compound of formula 1-1 was added to 450μί of ethyl acetate

• 0.00001M (10^"5M): 50μΙ. of 10^"4M solution of compound of formula 1-1 was added to 450μί of ethyl acetate

• 0.000001M (10^"6M): 50μί of 10^"5M solution of compound of formula 1-1 was added to 450μί of ethyl acetate Cells were grown in two dimensions on a plastic substrate, harvested in suspension in serum-free media, then the cells in the sample were trypsinized and a single cell suspension was formed by passing through a cell strainer. The cells were diluted according to the predetermined plating efficiency for the cell line being studied by suspending the cells in stem cell culture medium. 100 uL of this suspension was added into each well of a 96 well suspension plate, and the plate was incubated at 37 degrees Celsius in 5% C0₂ atmosphere for 24 hours, then 2 uL of appropriate concentrations of the drug were added into each respective well along with 100 uL of stem cell culture medium, and the plates incubated at 37 degrees Celsius under 5% C0₂ atmosphere for 72 hours. After incubation, 2.5 uL of the appropriate drug concentration was then added to each respective well along with 50 uL of stem cell culture medium, then the plates incubated at 37 degrees Celsius under 5% C0₂ atmosphere for further 72 hours. 3 uL of the appropriate drug concentration was added to each respective well along with 50 uL of stem cell culture medium, then incubated at 37 degrees Celsius under 5% C0₂ atmosphere for further 72 hours, then the spheres formed were observed under a microscope then counted and scored by size. Results of the in vitro 3D sphere forming stem cell assay for compound of formula 1-1 are set forth in Table 2. The number in each box is the total number of spheres formed in the presence of compound of formula 1-1 at each drug concentration. GC refers to a growth control performed in the absence of drug. GCEA refers to a growth control performed in the absence of drug or solvent ethyl acetate.

Table 2

Compound of formula 1-1 showed significant sphere reduction, it was found to be the most effective on breast, prostrate and ovarian cancer cells lines.

Claims

Claims:

I

or a pharmaceutically acceptable salt thereof, wherein:

n is 0-4;

m is 0-3;

p is 0-2;

each R³, R⁴ and R⁵ is independently halogen, -CN, -N02, -R, -OR, -SR, -N(R)₂, - N(R)C(0)R, C(0)RN(R)₂, -N(R)C(0)N(R)₂, -N(R)C(0)OR, -OC(0)N(R), -N(R)S0₂R, - S02RN(R)₂, C(0)R, -C(0)OR, -OC(0)R, -C(0)OR, -S(0)R, or -S0₂R;

R2 and R2' are taken together to form =0 or =S;

Q is -O-, -S-, or -N(R)-;

A is O or S;

R¹ is -OH, OR, -OC(0)R, or a protected hydroxyl group.

2. The compound of claim 1 wherein Ring B is a 4-8 membered partially unsaturated, or aromatic ring having 0-3 heteroatoms independently selected from nitrogen, oxygen, or sulfur.

3. The compound of claim 1 wherein Ring C is a 4-8 membered partially unsaturated or aromatic ring having 0-3 heteroatoms independently selected from nitrogen, oxygen, or sulfur.

4. The compound of claim 1 which is compound of formula II, III or IV or or a pharmaceutically acceptable salt thereof, wherein each variable is as per claim 1:

5. The compound of claim 1 in which compound is compound of formula I- 1, 1-2, 1-3, 1-4, 1-5 or 1-6 or a pharmaceutically acceptable salt thereof,

6. A use of a compound of formula I as described in claim 1, or a pharmaceutically acceptable salt thereof, to prepare a medicament useful for treating cancer in an animal.

7. A pharmaceutical composition comprising a compound of formula I as described in claim 1 or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable carrier.

8. A use of a compound of formula I as described in claim 1 or a pharmaceutically acceptable salt thereof or composition of claim 7 for inhibiting the proliferation or of or eradication of cancer cells and/or cancer cells having significant self-renewal potential, such as cancer stem cells in a patient.

9. A method of inhibiting proliferation of or eradication of cancer cells and/or cancer cells having significant self-renewal potential, such as cancer stem cells in a patient comprising the step of administering to said patient a compound of formula I of claim 1 or composition of claim 7.

10. The method according to claim 9, wherein said cancer cells and/or cancer cells having significant self-renewal potential, such as cancer stem cells are from the cell lines selected from but not limiting to breast, prostrate and ovarian cell lines.

11. The method according to claim 10, wherein said cell lines are selected from but not limiting to DU145, PC3, LNCaP, MDA MB 231, MCF7, T47D, MCF10A, HeLa, or L929.

12. The method according to claim 9, wherein said cancer is selected from breast, prostate, ovary, brain, blood, bone marrow, liver, pancreas, skin, kidney, colon, lung, testicle, penis, thyroid, parathyroid, pituitary, thymus, retina, uvea, conjunctiva, spleen, head, neck, trachea, gall bladder, rectum, salivary gland, adrenal gland, throat, esophagus, lymph nodes, sweat glands, sebaceous glands, muscle, heart, or stomach.

13. The method according to claim 9, wherein said compound is administered in combination with an additional at least one chemotherapeutic agent.