the prodrugs thereof, and the pharmaceutically acceptable salts of the compounds and prodrugs, wherein R
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[0001] This application claims priority to U.S. Provisional Application Serial No. 60/458,500, filed Mar. 27, 2003.
[0002] The invention relates to substituted 4-amino[1,2,4]triazolo[4,3-a]quinoxalines which are inhibitors of glycogen synthase kinase-3 (GSK-3) and, as such, are useful in the treatment of, inter alia, conditions, diseases, and symptoms such as diabetes, dementia, Alzheimer's Disease, bipolar disorder, stroke, schizophrenia, depression, hair loss, cancer, and the like.
[0003] Glycogen synthase kinase-3 (GSK-3), a proline-directed, serine/threonine kinase for which two isoforms; GSK-3α and GSK-3β, have been identified, phosphorylates the rate-limiting enzyme of glycogen synthesis, glycogen synthase (GS). See, for example, Embi, et al., Eur. J. Biochem., 107, 519-527 (1980). GSK-3α and GSK-3β are both highly expressed in the body. See, for example, Woodgett, et al., EMBO, 9, 2431-2438 (1990) and Loy, et al., J. Peptide Res., 54, 85-91 (1999). Besides GS, a number of other GSK-3 substrates have been identified, including many metabolic, signaling, and structural proteins. Notable among the plurality of signaling proteins regulated by GSK-3 are many transcription factors, including activator protein-1; cyclic AMP response element binding protein (CREB); the nuclear factor (NF) of activated T-cells; heat shock factor-1; β-catenin; c-Jun; c-Myc; c-Myb; and NF-
[0004] The present invention provides compounds of formula (I)
[0005] the prodrugs thereof, and the pharmaceutically acceptable salts of the compounds and prodrugs, wherein R
[0006] The present invention relates to compounds of formula (I)
[0007] the prodrugs thereof, and the pharmaceutically acceptable salts of the compounds and prodrugs, wherein:
[0008] R
[0009] (i) hydrogen;
[0010] (ii) acetyl;
[0011] (iii) —(C
[0012] (a) halogen; (b) —NR
[0013] R
[0014] (j) hydrogen; (k) amidino; (l) aryl, optionally, and independently, substituted with from 1-3 of halogen; cyano; nitro; —(C
[0015] R
[0016] R
[0017] (iv) —(C
[0018] (v) —(C
[0019] R
[0020] R
[0021] provided that when R
[0022] A generally preferred subgroup of the compounds of formula (I) comprises those compounds wherein:
[0023] R
[0024] R
[0025] R
[0026] R
[0027] Another generally preferred subgroup of the compounds of formula (I) comprises those compounds wherein:
[0028] R
[0029] R
[0030] R
[0031] R
[0032] The compounds and intermediates of the present invention may be named according to either the IUPAC (International Union for Pure and Applied Chemistry) or CAS (Chemical Abstracts Service, Columbus, Ohio) nomenclature systems.
[0033] The carbon atom content of the varicus hydrocarbon-containing moieties may be indicated by a prefix designating the minimum and maximum number of carbon atoms in the moiety, i.e., the prefix —(C
[0034] The term “alkoxy” denotes straight or branched, monovalent, saturated aliphatic chains of carbon atoms bonded to an oxygen atom, wherein the alkoxy group optionally incorporates one or more double or-triple bonds, or a combination of double bonds and triple bonds. Examples of alkoxy groups include methoxy, ethoxy, propoxy, butoxy, iso-butoxy, tert-butoxy, and the like.
[0035] The term “alkyl” denotes straight, or branched, monovalent chains of carbon atoms, wherein the alkyl group optionally incorporates one or more double or triple bonds, or a combination of double bonds and triple bonds. Examples of alkyl groups include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, vinyl, allyl, 2-methylpropenyl, 2-butenyl, 1,3-butadienyl, ethynyl, propargyl, and the like.
[0036] The term “aryl” denotes a monocyclic, or polycyclic, aromatic hydrocarbon.
[0037] Examples of aryl groups include anthracenyl, fluorenyl, phenanthrenyl, phenyl, naphthyl, and the like.
[0038] The term “cycloalkyl” denotes a saturated monocyclic, or polycyclic, cycloalkyl group, optionally fused to an aryl group, wherein the cycloalkyl group optionally incorporates one or more double or triple bonds, or a combination of double bonds and triple bonds, but which is not aromatic. Examples of cycloalkyl groups include adamantanyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, decahydronaphthalinyl, norbornanyl, and the like.
[0039] The term “halogen” represents chloro, fluoro, bromo, and iodo.
[0040] The term “heteroaryl” denotes a monocyclic, or polycyclic, aromatic hydrocarbon group wherein one or more carbon atoms have been replaced with heteroatoms selected from the group consisting of nitrogen, oxygen, and sulfur. If the heteroaryl group contains more than one heteroatom, the heteroatoms may be the same or different. Examples of heteroaryl groups include acridinyl, benzofuranyl, benzothienyl, benzimidazolyl, benzoxazolyl, benzothiazolyl, chromenyl, cinnolinyl, furyl, imidazolyl, indazolyl, indolizinyl, indolyl, isobenzofuranyl, isoindolyl, isoquinolyl, isothiazolyl, isoxazolyl, naphthyridinyl, oxadiazolyl, oxazinyl, oxazolyl. phenazinyl, phthalaziriyl, pteridinyl, purinyl, pyranyl, pyrazinyl, pyrazolyl, pyridazinyl, pyrido[3,4-b]indolyl, pyridyl, pyrimidyl, pyrrolyl, quinolizinyl, quinolyl, quinoxalinyl, thiadiazolyl, thiatriazolyl, thiazolyl, thienyl, triazinyl, triazolyl, xanthenyl, and the like.
[0041] The term “heterocycloalkyl” denotes a saturated monocyclic, or polycyclic, cycloalkyl group, optionally fused to an aromatic or heteroaromatic hydrocarbon group, in which at least one of the carbon atoms has been replaced with a. heteroatom selected from the group consisting of nitrogen, oxygen, and sulfur.. If the heterocycloalkyl group contains more than one heteroatom, the heteroatoms may be the same or different. Examples of such heterocycloalkyl groups include azabicycloheptanyl, azetidinyl, benzazepinyl, 1,3-dihydroisoindolyl, dioxolanyl, dioxanyl, carbazolyl, dioxolanyl, dithianyl, indolinyl, imidazolidinyl, morpholinyl, quinuclidinyl, phenothiazinyl, phenoxazinyl, piperazinyl, piperidyl, pyrazolidinyl, pyrrolidinyl, tetrahydrofuryl, tetrahydroindolyl, tetrahydroisoquinolinyl, tetrahydropyranyl, tetrahydroquinolinyl, tetrahydroquinoxalinyl, tetrahydrothiopyranyl, tetrahydro-2H-1,4-thiazinyl, thiazolidinyl, thiomorpholinyl, thioxanthenyl, thioxanyl, trithianyl, and the like.
[0042] A cyclic group may be bonded to another group in more than one way. If no particular bonding arrangement is specified, then all possible arrangements are intended. For example, the term “pyridyl” includes 2-, 3-, or 4-pyridyl, and the term “thienyl” includes 2- or 3-thienyl.
[0043] The term “mammal” means animals including, for example, dogs, cats, cows, sheep, horses, and humans. Preferred mammals include humans of either gender.
[0044] The phrase “pharmaceutically acceptable” indicates that the designated carrier, vehicle, diluent, excipient(s), and/or salt must be chemically and/or physically compatible with the other ingredients comprising the formulation, and physiologically compatible with the recipient thereof.
[0045] The term “prodrug” refers to a compound that is a drug precursor which, following administration, releases the drug in vivo via a chemical or physiological process (e.g., upon being brought to physiological pH or through enzyme activity). A discussion of the preparation and use of prodrugs is provided by T. Higuchi and W. Stella, “Prodrugs as Novel Delivery Systems, Vol. 14 of the ACS Symposium Series, and in Bioreverible Carriers in Drug Design, ed. Edward B. Roche, American Pharmaceutical Association and Pergamon Press, 1987.
[0046] The term “radical” denotes a group of atoms that behaves as a single atom in a chemical reaction, e. g., an organic radical is a group of atoms that imparts characteristic properties to a compound containing it, or which remains unchanged during a series of reactions, or transformatiens.
[0047] The term “salts” refers to organic and inorganic salts of a compound of formula (I), or a prodrug thereof. These salts can be prepared in situ during the final isolation and purification of a compound, or by separately reacting a compound of formula (I), or a prodrug thereof, with a suitable organic or inorganic acid or base arid isolating the salt thus formed. Representative salts include the hydrobromide, hydrochloride, sulfate, bisulfate, nitrate, acetate, oxalate, besylate, palrnitate, stearate, laurate, borate, benzoate, lactate, phosphate, tosylate, citrate, maleate, fumarate, succinate, tartrate, naphthylate, mesylate, glucoheptonate, lactobionate, and laurylsulphonate salts, and the like. These may also include cations based on the alkali and alkaline earth metals, such as sodium, lithium, potassium, calcium, magnesium, and the like, as well as non-toxic ammonium, quaternary ammonium, and amine cations including, but not limited to, ammonium, tetramethylammonium, tetraethylammonium, methylamine, dimethylamine, trimethylamine, triethylamine, ethylamine, and the like. For additional examples see, for example, Berge, et al., J. Pharm. Sci., 66, 1-19 (1977).
[0048] The term “substituted” means that a hydrogen atom on a molecule has been replaced with a different atom or molecule. The atom or molecule replacing the hydrogen atom is denoted as a “substituent.”
[0049] The symbol “—” represents a covalent bond.
[0050] The phrase “reaction-inert solvent” or “inert solvent” refers to a solvent, or mixture of solvents, that does not interact with starting materials, reagents, intermediates, or products in a manner that adversely affects their desired properties.
[0051] The terms “treating”, “treated”, or “treatment” as employed herein includes preventative (e.g., prophylactic), palliative, or curative use or result.
[0052] The compounds of formula (I) may contain asymmetric or chiral centers and, therefore, exist in different stereoisomeric forms. It is intended that all stereoisomeric forms of the compounds and prodrugs of formula (I) as well as mixtures thereof, including racemic mixtures, form part of the present invention. In addition, the present invention embraces all geometric and positional isomers. For example, if a compound or prodrug of formula (I) incorporates a double bond, both the cis- and trans-forms, as well as mixtures thereof, are embraced within the scope of the invention.
[0053] Diastereomeric mixtures can be separated into their individual diastereomers on the basis of their physical chemical differences by methods well-known to those of ordinary skill in the art, such as by chromatography and/or fractional crystallization. Enantiomers can be separated by converting the enantiomeric mixture into a diasteriomeric mixture by reaction with an appropriate optically active compound (e.g., alcohol), separating the diasteriomers and converting (e.g., hydrolyzing) the individual diasteriomers to the corresponding pure enantiomers. Also, some of the compounds of formula (I) may be atropisomers (e.g., substituted biaryls) and are also considered as part of the invention.
[0054] The compounds and prodrugs of formula (I) may exist in unsolvated as well as solvated forms with pharmaceutically acceptable solvents, such as water, ethanol, and the like, and it is intended that the invention embrace both solvated and unsolvated forms.
[0055] It is also possible that the compounds and prodrugs of formula (I) may exist as tautomeric isomers in equilibrium, and all such forms are embraced within the scope of the invention.
[0056] The present invention also embraces isotopically-labeled compounds of formula (I), which are identical to those recited herein, but for the fact that one or more atoms are replaced by an atom having an atomic mass or mass number different from the atomic mass or mass number usually found in nature. Examples of isotopes that can be incorporated into compounds of formula (I) include isotopes of hydrogen, carbon, nitrogen, oxygen, phosphorus, fluorine, and chlorine, such as
[0057] Certain isotopically-labeled compounds of formula (I), for example those compounds into which radioactive isotopes such as
[0058] In another aspect, the invention provides methods of treating glycogen synthase kinase-3-mediated conditions, diseases, or symptoms in a mammal in need of such treatment which comprise administering to a mammal in need of such treatment a therapeutically effective amount of a compound of formula (I), a prodrug thereof, or a pharmaceutically acceptable salt of the compound or prodrJg; a pharmaceutical composition comprising a compound of formula (I), a prodrug thereof, or a pharmaceutically acceptable salt of the compound or prodrug, and a pharmaceutically acceptable carrier, vehicle, or diluent; or a combination of an amount of a compound of formula (I), a prodrug thereof, or a pharmaceutically acceptable salt of the compound or prodrug, and an amount of one or more of: (i) an anti-angiogenesis agent, (ii) a signal transduction inhibitor, (iii) an anti-proliferative agent, (iv) an NK-1 receptor antagonist, (v) a 5HT
[0059] Preferred conditions, diseases, and symptoms treatable according to the instant methods are those selected from the group consisting of Alzheimer's Disease, asthma, atherosclerosis, anxiety, bipolar disorder, cancer, diabetes, dementia, depression, frailty, hair loss, heart failure, essential hypertension, hyperglycemia, hyperlipidemia, hypoglycemia, inflammation, ischemia, male fertility and sperm motility, mood disorders, neuronal cell death, obesity, obsessive compulsive disorder, polycystic ovary disorder, schizophrenia, stroke, Syndrome X, and traumatic brain injury. An especially preferred disease treatable according to the instant methods is diabetes.
[0060] Frailty is characterized by the progressive and relentless loss of skeletal muscle mass resulting in a high risk of injury from fall, difficulty in recovery from illness, prolongation of hospitalization, and long-term disability requiring assistance in daily living. The reduction of muscle mass and physical strength typically leads to diminished quality of life, loss of independence, and mortality. Frailty is normally associated with aging, but may also result when muscle loss and reduced strength occur due to other factors, such as disease-induced cachexia, immobilization, or drug-induced sarcopenia. Another term that has been used to denote frailty is sarcopenia, which is a generic term for the loss of skeletal muscle mass, or quality. Examples of skeletal muscle properties that contribute to its overall quality include contractility, fiber size and type, fatiguability, hormone responsiveness, glucose uptake/metabolism, and capillary density.
[0061] Generally preferred anti-angiogenesis agents may comprise, for example, matrix metalloproteinase-2 (MMP-2) inhibitors, matrix metalloproteinase-9 (MMP-9) inhibitors, and cyclooxygenase-II (COX-II) inhibitors. Examples of useful MMP-2 and MMP-9 inhibitors are disclosed in, for example, PCT International Application Publication Nos. WO 98/34915 and WO 98/34918, and U.S. Pat. Nos. 5,240,958; 5,310,763; 5,455,258; 5,506,242; 5,530,161; 5,552,419; 5,672,615; 5,861,510; 5,863,949; 5,932,595; 5,994,351; 6,077,864; 6,087,392; 6,090,852; 6,110,964; 6,147,061; 6,147,074; 6,303,636; 6,380,219; and 6,387,931. Examples of COX-II inhibitors useful in the present combinations and methods comprise CELEBREX® (celecoxib, U.S. Pat. No. 5,466,823), valdecoxib (U.S. Pat. No. 5,633,272), and rofecoxib (U.S. Pat. No. 5,474,995). Generally preferred MMP-2 and MMP-9 inhibitors are those that exhibit little or no activity inhibiting MMP-1. Especially preferred MMP-2 and MMP-9 inhibitors are those that selectively inhibit MMP-2 and/or MMP-9 relative to other MMP inhibitors, i.e., MMP-1, MMP-3, MMP-4, MMP-5, MMP-6, MMP-7, MMP-8, MMP-10, MMP-11, MMP-12, and MMP-13. Specific examples of MMP inhibitors useful in the present combinations and methods comprise AG-3340, RO 32-3555, RS 13-0830, and the following compounds:
[0062] 3-[[4-(4-fluoro-phenoxy)-benzenesulfonyl]-(1-hydroxycarbamoy l-cyclopentyl)-amino]-propionic acid;
[0063] 3-exo-3-[4-(4-fluoro-phenoxy)-benzenesulfonyl-amino]-8-oxa-b icyclo[3.2.1]octane-3-carboxylic acid hydroxyamide;
[0064] (2R,3R) 1-[4-(2-chloro-4-fluoro-benzyloxy)-benzenesulfonyl]-3-hydrox y-3-methyl-piperidine-2-carboxylic acid hydroxyamide;
[0065] 4-[4-(4-fluoro-phenoxy)-benzenesulfonyl-amino]-tetrahydro-py ran-4-carboxlyic acid hydroxyamide;
[0066] 3-[[4-(4-fluoro-phenoxy)-benzenesulfonyl]-(1-hydroxycarbamoy l-cyciobutyl)-amino]-propionic acid;
[0067] 4-[4-(4-chloro-pherioxy)-benzenesulfonyl-amino]-tetrahydro-p yran-4-carboxlyic acid hydroxyamide;
[0068] (R)-3-[4-(4-chloro-phenoxy)-benzenesulfonyl-amino]-tetrahydr o-pyran-3-carboxlyic acid hydroxyamide;
[0069] (2R,3R) 1-[4-(4-fluoro-2-methyl-benzyloxy)-benzenesulfonyl]-3-hydrox y-3-methyl-piperidine-2-carboxylic acid hydroxyamide;
[0070] 3-[[4-(4-fluoro-phenoxy)-benzenesulfonyl]-(1-hydroxycarbamoy l-1 -methyl-ethyl)-amino]-propionic acid;
[0071] 3-[[4-(4-fluoro-phenoxy)-benzenesulfonyl]-(4-hydroxycarbamoy l-tetrahydro-pyran-4-yl)-amino[-propionic acid;
[0072] 3-exo-3-[4-(4-chloro-phenoxy)-benzenesulfonyl-amino]-8-oxa-b icyclo[3.2.1 ]octane-3-carboxylic acid hydroxyamide;
[0073] 3-endo-3-[4-(4-fluoro-phenoxy)-benzenesulfonyl-amino]-8-oxa- bicyclo[3.2.1]octane-3-carboxylic acid hydroxyamide; and
[0074] (R)-3-[4-(4-fluoro-phenoxy)-benzenesulfonyl-amino]-tetrahydr o-furan-3-carboxlyic acid hydroxyamide; and the pharmaceutically acceptable salts and solvates thereof.
[0075] Generally preferred signal transduction inhibitors may comprise, for example, epidermal growth factor receptor (EGFR) response inhibitors, such as EGFR antibodies, EGF antibodies, and molecules that are EGFR inhibitors; vascular endothelial growth factor (VEGF) inhibitors; and erbB2 receptor inhibitors, such as molecules or antibodies that bind to the erbB2 receptor, for example, HERCEPTIN® (Genentech Inc.; South San Francisco, Calif.). EGFR inhibitors are described in, for example, PCT International Application Publication No. WO 98/14451, and U.S. Pat. Nos. 5,679,683; 5,747,498; and 6,391,874. EGFR-inhibiting agents may comprise, for example, the monoclonal antibodies C225 and anti-EGFR 22Mab (Imclone Systems, Inc.), ZD-1839, BIBX-1382, MDX-103, VRCTC-310, and EGF fusion toxin (Seragen Inc.; Hopkinton, Mass.). VEGF inhibitors are disclosed in, for example, PCT International Application Publication No. WO 99/24440, and U.S. Pat. Nos. 5,792,783; 5,834,504; 5,851,999; 5,883,113; 5,886,020; 6,051,593; 6,114,371; 6,133,305; 6,162,804; 6,174,889; 6,207,669; 6,235,741; 6,291,455; 6,294,532; 6,310,238; 6,380,203; and 6,395,734. Specific VEGF inhibitors may comprise, for example, Su-5416, IM862, anti-VEGF monoclonal antibody (Cytran Inc.; Kirkland, Wash.), and angiozyme (Ribozyme; Boulder, Colo.). ErbB2 receptor inhibitors are disclosed in, for example, PCT International Application Publication Nos. WO 97/13760, WO 99/35132, and WO 99/35146, and U.S. Pat. Nos. 5,679,683; 5,587,458; 5,877,305; 6,207,669; and 6,391,874. Specific erbB2 receptor inhibitors may comprise, for example, GW-282974 (Glaxo Wellcome plc.), and the monoclonal antibody AR-209 (Aronex Pharmaceuticals Inc.; The Woodlands, Tex.).
[0076] Generally preferred anti-proliferative agents may comprise, for example, cytotoxic lymphocyte antigen 4 (CTLA4) antibodies, and other agents capable of blocking CTLA4; and farnesyl transferase inhibitors.
[0077] Examples of NK-1 receptor antagonists are disclosed in, for example, U.S. Pat. Nos. 5,122,525; 5,162,339; 5,232,929; 5,332,817; 5,703,240; 5,716,965; 5,719,147; 5,744,480; 5,763,699; 5,773,450; 5,807,867; 5,843,966; 5,852,038; 5,886,009; and 5,939,433.
[0078] Examples of 5HT
[0079] Examples of SSRI's useful in the present combinations and methods may comprise, for example, fluoxetine (U.S. Pat. No. 4,314,081), paroxetine (U.S. Pat. No. 4,007,196), sertraline (U.S. Pat. No. 4,536,518), fluvoxamine (U.S. Pat. No. 4,085,225), venlafaxine hydrochloride (EFFEXOR®, U.S. Pat. No. 4,535,186), nefazodone hydrochloride (SERZONE®, U.S. Pat. No. 4,338,317), and bupropion hydrochloride (WELLBUTRIN®, U.S. Pat. Nos. 3,819,706 and 3,885,046).
[0080] Generally preferred anti-psychotic agents useful in the present combinations and methods may comprise, for example, ziprasidone (GEODON®, U.S. Pat. No. 5,312,925), olanzapine (U.S. Pat. No. 5,229,382), risperidone (U.S. Pat. No. 4,804,663), L-745,870, sonepiprazole, RP-62203 (fananserin), NGD-941, balaperidone, flesinoxan (U.S. Pat. No. 4,833,142), and gepirone (U.S. Pat. No. 4,423,049).
[0081] Generally preferred acetylcholinesterase inhibitors useful in the present combinations and methods may comprise, for example, donepezil (ARICEPT®, U.S. Pat. No. 4,895,841), rivastigmine (EXELON®, U.S. Pat. No. 4,948,807), metrifonate (U.S. Pat. No. 2,701,225), galanthamine, physostigmine, tacrine, huperzine, and. icopezil (U.S. Pat. No. 5,538,984).
[0082] Generally preferred neuroprotectants useful in the instant combinations and methods may comprise, for example, NMDA receptor antagonists. Specific NMDA receptor antagonists comprise, for example, (1S,2S)-1-(4-hydroxyphenyl)-2-(4-hydroxy-4-phenylpiperidin-1 -yl)-1-propanol (U.S. Pat. No. 5,272,160); eliprodil (U.S. Pat. No. 4,690,931); and gavestenel (U.S. Pat. No. 5,373,018). Examples of additional NMDA antagonists are disclosed in, for example, U.S. Pat. Nos. 4,690,931; 5,185,343; 5,272,160; 5,356,905; 5,373,018; 5,744,483; 5,962,472; 6,046,213; 6,124,317; 6,124,323; 6,130,234; 6,218,404; 6,333,036; and 6,448,270; and in PCT International Application Publication Nos. WO 97/23202 and WO 98/18793.
[0083] A generally preferred potassium channel modulator comprises, for example, BMS-204352 (flindokaliner, U.S. Pat. No. 5,602,169).
[0084] The disclosures of all of the above U.S. patents are incorporated herein in their entirety by reference.
[0085] In another aspect, the invention provides methods for inhibiting glycogen synthase kinase-3 activity in a mammal in need of such inhibition which comprise administering a glycogen synthase kinase-3 inhibiting amount of a compound of formula (I), a prodrug thereof, or a pharmaceutically acceptable salt of the compound or prodrug; or a pharmaceutical composition comprising a compound of formula (I), a prodrug thereof, or a pharmaceutically acceptable salt of the compound or prodrug, and a pharmaceutically acceptable carrier, vehicle, or diluent.
[0086] The compounds of formula (I), the prodrugs thereof, and the pharmaceutically acceptable salts of the compounds and prodrugs, may be administered to a mammal at dosage levels in the range of from about 0.0001 mg to about 1,000 mg per day. For a normal adult human having a body mass of about 70 kg, a dosage in the range of from about 0.01 mg to about 500 mg per kg body mass is typically sufficient. However, some variability in the general dosage range may be required depending upon the age and mass of the subject being treated, the intended route of administration, the particular compound being administered, and the like. The determination of dosage ranges and optimal dosages for a particular mammalian subject is within the ability of one of ordinary skill in the art having benefit of the instant disclosure.
[0087] According to the methods of the present invention, the compounds of formula (I), the prodrugs thereof, and the pharmaceutically acceptable salts of the compounds and prodrugs, or the aforementioned combinations thereof with the amounts of one or more of: (i) an anti-angiogenesis agent, (ii) a signal transduction inhibitor, (iii) an anti-proliferative agent, (iv) an NK-1 receptor antagonist, (v) a 5HT
[0088] Pharmaceutical compositions suitable for parenteral injection may comprise pharmaceutically acceptable sterile aqueous or nonaqueous solutions, dispersions, suspensions, or emulsions, and sterile powders for extemporaneous reconstitution into sterile injectable solutions or dispersions. Examples of suitable aqueous and nonaqueous carriers, vehicles, and diluents include water, ethanol, polyols (such as propylene glycol, polyethylene glycol, glycerol, and the like), suitable mixtures thereof, vegetable oils (such as olive oil), and injectable organic esters such as ethyl oleate. Proper fluidity can be maintained, for example, by the use of a coating such as lecithin, by the maintenance of the required particle size in the case of dispersions, and by the use of surfactants.
[0089] The pharmaceutical compositions of the invention may further comprise adjuvants, such as preserving, wetting, emulsifying, and dispersing agents. Prevention of microorganism contamination of the instant compositions can be accomplished with various antibacterial and antifungal agents, for example, parabens, chlorobutanol, phenol, sorbic acid, and the like. It may also be desirable to include isotonic agents, for example, sugars, sodium chloride, and the like. Prolonged absorption of injectable pharmaceutical compositions may be effected by the use of agents capable of delaying absorption, for example, aluminum monostearate and gelatin.
[0090] Solid dosage forms for oral administration include capsules, tablets, powders, and granules. In such solid dosage forms, the active compound is admixed with at least one inert conventional pharmaceutical excipient (or carrier) such as sodium citrate or dicalcium phosphate, or (a) fillers or extenders, as for example, starches, lactose, sucrose, mannitol, and silicic acid; (b) binders, as for example, carboxymethylcellulose, alginates, gelatin, polyvinylpyrrolidone, sucrose, and acacia; (c) humectants, as for example, glycerol; (d) disintegrating agents, as for example, agar-agar, calcium carbonate, potato or tapioca starch, alginic acid certain complex silicates, and sodium carbonate; (e) solution retarders, as for example, paraffin; (f) absorption accelerators, as for example, quaternary ammonium compounds; (g) wetting agents, as for example, cetyl alcohol and glycerol monostearate; (h) adsorbents, as for example, kaolin and bentonite; and/or (i) lubricants, as for example, talc, calcium stearate, magnesium stearate, solid polyethylene glycols, sodium lauryl sulfate, or mixtures thereof. In the case of capsules and tablets, the dosage forms may further comprise buffering agents.
[0091] Solid compositions of a similar type may also be employed as fillers in soft or hard filled gelatin capsules using such excipients as lactose or milk sugar, as well as high molecular weight polyethylene glycols, and the like.
[0092] Solid dosage forms such as tablets, dragees, capsules, and granules can be prepared with coatings and shells, such as enteric coatings and others well-known to one of ordinary skill in the art. They may also comprise opacifying agents, and can also be of such composition that they release the active compound(s) in a delayed, sustained, or controlled manner. Examples of embedding compositions that can be employed are polymeric substances and waxes. The active compound(s) can also be in micro-encapsulated form, if appropriate, with one or more of the above-mentioned excipients.
[0093] Liquid dosage forms for oral administration include pharmaceutically acceptable emulsions, solutions, suspensions, syrups, and elixirs. In addition to the active compounds, the liquid dosage form may contain inert diluents commonly used in the art, such as water or other solvents, solubilizing agents and emulsifiers, as for example, ethyl alcohol, isopropyl alcohol, ethyl carbonate, ethyl acetate, benzyl alcohol, benzyl benzoate, propylene glycol, 1,3-butylene glycol, dimethylformamide, oils, in particular, cottonseed oil, groundnut oil, corn germ oil, olive oil, castor oil, and. sesame seed oil, glycerol, tetrahydrofurfuryl alcohol, polyethylene glycols and fatty acid esters of sorbitan, or mixtures of these substances, and the like.
[0094] Besides such inert diluents, the pharmaceutical composition can also include adjuvants, such as wetting agents, emulsifying and suspending agents, sweetening, flavoring, and perfuming agents.
[0095] Suspensions, in addition to the active compound(s), may further comprise suspending agents, as for example, ethoxylated isostearyl alcohols, polyoxyethylene sorbitol and sorbitan esters, microcrystalline cellulose, aluminum metahydroxide, bentonite, agar-agar, and tragacanth, or mixtures of the aforementioned substances, and the like.
[0096] Compositions for rectal or vaginal administration preferably comprise suppositories, which can be prepared by mixing an active compound(s) with suitable non-irritating excipients or carriers such as cocoa butter, polyethylene glycol or a suppository wax, which are solid at ordinary room temperature, but liquid at body temperature, and therefore, melt in the rectum or vaginal cavity thereby releasing the active component.
[0097] Dosage forms for topical administration may comprise ointments, powders, sprays and inhalants. The active agent(s) are admixed under sterile condition with a pharmaceutically acceptable carrier, vehicle, or diluent, and any preservatives, buffers, or propellants that may be required.
[0098] The compounds of formula (I), the prodrugs thereof, and the pharmaceutically acceptable salts of the compounds and prodrugs, may be prepared according to the exemplary synthetic routes disclosed in the Schemes and Examples hereinbelow, as well as by other conventional organic preparative methods known, or apparent in light of the instant disclosure, to one of ordinary skill in the relevant art. It is to be understood that the methods disclosed in the instant Schemes are intended for purposes of exemplifying the instant invention, and are not to be construed in any manner as limitations thereon.
[0099] A generalized method for preparing the compounds of formula (I) is depicted in Scheme 1 hereinbelow. Alternative synthetic routes for the preparation of compounds of formula (I) wherein R
[0100] In Scheme 1, an appropriately-substituted 1,2-diaminophenyl derivative (1) is cyclocondensed with diethyl oxalate and the resulting quinoxaline-2,3-dione is heated in the presence of neat phosphorus oxychloride, or thionyl chloride and a catalytic amount of dimethylformamide (DMF), to afford the substituted 2,3-dichloroquinoxaline (2). Typically, the cyclocondensation is effected at elevated temperature, preferably at, or about, 180° C. Treatment of quinoxaline (2) with hydrazine in a protic solvent, preferably ethanol, followed by heating with tetramethyl orthocarbonate in a reaction-inert solvent, such as toluene, affords the substituted 4-chloro-1-methoxy[1,2,4]triazolo[4,3-a]quinoxaline derivative (3). Displacement of the chlorine atom of (3) with an appropriately-substituted amine R
[0101] Alternatively, the compounds of formula (I) wherein R
[0102] In Scheme 2, a mono-protected (preferably tert-butoxycarbonyl; t-BOC) alkylenediamine, is first reacted with a 4-chloro-1-methoxyquinoxaline derivative (3) to afford a protected diaminoquinoxaline derivative. Typically, the reaction is effected in the presence of an organic base, such as triethylamine, in a reaction-inert solvent, such as acetonitrile, at above ambient temperature. Subsequent exposure of this product to HBr/AcOH at elevated temperature removes both the imidate ether and the protecting group to provide diaminoquinoxaline (4). Reaction of (4) with R
[0103] Alternatively, the compounds of formula (I) wherein R
[0104] In Scheme 3 hereinabove, an 8-bromo-4-amino-1-methoxyquinoxaline derivative (5) is converted into the corresponding 8-carbomethoxy derivative under Heck Reaction conditions. Generally, a solution of (5) containing an organic base, such as triethylamine, a Pd source, preferably Pd(II)acetate and a soluble ligand, such as bis-diphenylphosphinopropane (dppp), and the alcohol precursor to the desired ester product in a polar solvent, preferably DMSO (dimethylsulfoxide), is heated under an atmosphere of carbon monoxide gas at elevated temperature, normally 45 psi. These conditions are typically sufficient to cleave the methyl ether and generate the corresponding carbonyl group in the desired product. Saponification of the resulting ester with an inorganic base, such as sodium hydroxide, in a polar, protic solvent mixture, preferably tetrahydrofuran (THF)/methanol, provides the corresponding carboxylic acid, which is converted into amide (Ib) with an appropriately-substituted amine R
[0105] Alternatively, the compounds of formula (I) wherein R
[0106] In Scheme 4, a 4-amino-7-carboxymethyl-1-methoxyquinoxaline derivative (6) is saponified, typically with base, for example, sodium hydroxide, to provide the corresponding sodium salt (7). The saponification is conveniently effected in a methano/THF mixture. Treatment of the carboxylate salt with aqueous acid generates the free acid, and hydrolyzes the imidate functionality to afford a triazolone carboxylic acid. The acid may then be converted into the corresponding amide (Id), and/or amine (Ie) according to the methods described hereinabove in Scheme 3. Alternatively, the reduction of amide (Id) may be effected with sodium borohydride and a Lewis Acid additive, preferably boron trifluoride etherate, in a reaction-inert solvent, such as THF.
[0107] Alternatively, (7) may be converted into the corresponding N-methyl-N-methoxyamide with a coupling reagent, preferably EDC in the presence of HOBT in a polar, aprotic solvent, such as DMF. The resulting adduct is then treated with a hydride reducing agent, preferably LAH, in a reaction-inert solvent, typically THF, at below ambient temperature, generally at −78° C., to form aldehyde (8). Subsequently, the amine functionality may be appended by reductive amination whereby aldehyde (8) is admixed with an appropriately-substituted amine R
[0108] Alternatively, the compounds of formula (Ib) depicted in Scheme 4, may also be conveniently prepared according to the exemplary method shown in Scheme 5.
[0109] In Scheme 5, the quinoxaline sodium salt (7) is treated with an appropriately-substituted amine R
[0110] Unless otherwise noted, all reagents employed were obtained commercially. Unless otherwise noted, the following experimental abbreviations have the meanings indicated:
[0111] AcOH—acetic acid
[0112] DMF—dimethylformamide
[0113] DMSO—dimethylsulfoxide
[0114] EDC 1-[3-(dimethy/amino)propyl]-3-ethylcarbodiimide hydrochloride
[0115] equiv.—equivalent(s)
[0116] EtOAc—ethyl acetate
[0117] EtOH—ethanol
[0118] HPLC—high performance liquid chromatography
[0119] HOBT—1-hydroxybenzotriazole
[0120] hr(s).—hour(s)
[0121] MeOH—methanol
[0122] min(s).—minute(s)
[0123] IPE—diisopropyl ether
[0124] IPA—isopropanol
[0125] LAH—lithium aluminum hydride
[0126] mL—milliliter(s)
[0127] mmol—millimole(s)
[0128] MS—mass spectrometry
[0129] NMR—nuclear magnetic resonance
[0130] THF—tetrahydrofuran
[0131] TLC—thin layer chromatography
[0132] TF—trifluoroacetic acid
[0133] The amine starting materials of formula R
[0134] The various 4-chloro-1-methoxy-[1,2,4]triazolol4,3-a]quinoxaline starting materials were prepared according to the method of R. Sarges, et al., J. Med. Chem., 33, 2240(1990).
[0135] Preparation 1
[0136] A mixture of 120 mg of 4-chloro-7-trifluoromethylquinoline and 250 mg of tert-butyl-N-(2-aminoethyl)carbamate was heated to 125° C. for two hrs. The mixture was cooled to room temperature and partitioned between 10% IPA/chloroform and saturated sodium bicarbonate. The aqueous layer was back extracted with 10% IPA/chloroform and the organic layers were dried over sodium sulfate, filtered and concentrated. The residue was dissolved in EtOAc and washed with water, and the organic layer was dried over sodium sulfate, filtered, and concentrated. The product was dissolved in MeOH (0.5 mL) and stirred with five equiv. of 4.0 M HCl in dioxane for 18 hrs. The reaction mixture was concentrated and the residue was recrystallized from MeOH to afford the title compound. MS (M+H)
[0137] The following 1,2- and 1,3-diamines were prepared in a manner analogous to that described in Preparation 1 using appropriate starting materials.
MS Prep'n. Name (M + H) 2 N 205.1 ethane-1,2-diamine 3 N 176.1 4 N 194.1 5 N 220.1 propane-1,3-diamine 6 N 220.2 propane-1,3-diamine 7 N 254.1 ethane-1,2-diamine 8 N 254.1 ethane-1,2-diamine 9 N 254.1 ethane-1,2-diamine 10 N 226.0 1,2-diamine 11 N 222.1 1,2-diamine 12 2-(2-amino-ethylamino)-isonicotinic acid 180.2
[0138] Preparation 13
[0139] A solution of 100 mg of N-methylethylenediamine, 245 mg of 2-chloro-5-trifluoromethylpyridine and 261 mg of diisopropylethylamine in toluene was heated at 110° C. for 18 hrs. The reaction mixture was concentrated, poured into water, and extracted with 10% PA/chloroform. The organic extracts were dried over sodium sulfate, filtered, and concentrated to provide the desired title compound contaminated with <3% of the bis-substituted dimer. MS (M+H)
[0140] The following 1,2-diamines were prepared in a manner analogous to that described in Preparation 13 using appropriate starting materials.
MS Prep'n. Name (M + H) 14 N 177.2 2-diamine 15 N 206.4 ethane-1,2-diamine 16 N 138.1 17 N 206.4 18 N 137.9 19 N 139.1
[0141] Preparation 20
[0142] A mixture of 1.32 g of ethylenediamine, 250 mg of 3-chloropyridine, and 740 mg of potassium tert-butoxide was heated at 118° C. in a sealed tube for 18 hrs. The reaction was cooled to room temperature, diluted with water and extracted with chloroform. The organic extracts were dried over sodium sulfate, filtered, and concentrated to give the title product as a red oil. MS (M+H)
[0143] Preparation 21
[0144] Step A
[0145] A solution of 434 mg of tert-butyl-N-(2-aminoethyl)carbamate and 576 mg of sodium carbonate in DMF (9.0 mL) at 0° C. was stirred as a solution of 500 mg of cyanuric chloride in DMF (2.0 mL) was added. The reaction mixture was stirred at 0° C. for two hrs., at room temperature for three hrs., and then poured into water to form a white suspension. The solid was collected and the filtrate was extracted with EtOAc and concentrated to provide a crude sample. The solids were combined and separated by silica gel chromatography to give the mono-ethylamine adduct.
[0146] Step B
[0147] The product from Step A was dissolved in absolute EtOH (7.6 mL) and 50 mg of 10% Pd/C was added, followed by 480 mg of ammonium formate. The mixture was heated at reflux for one hr., the solids were removed by filtration through diatomaceous earth, and washed with hot EtOH. The filtrate was concentrated to give a white solid.
[0148] Step C
[0149] The product of Step B was dissolved in MeOH (1.9 mL) and stirred together with 5 equiv. of 4.0 M HCI in dioxane for two hrs. The white solid that formed was collected and dried to give the title compound as the hydrochloride salt. MS (M+H)
[0150] Preparation 22
[0151] Step A
[0152] To a solution of 220 mg of N-methyl-4-piperidone and 283 mg of tert-butyl-(2-amino-ethyl)carbamate in methylene chloride (6.0 mL) was added 563 mg of sodium triacetoxyborohydride and 212 mg of acetic acid. This mixture was stirred at room temperature for 12 days and quenched by the addition of 1 N sodium hydroxide, followed by extraction with methylene chloride (4×). The extracts were dried over sodium sulfate, filtered, and concentrated to give a yellow, oily product.
[0153] Step B
[0154] The product of Step A was dissolved in MeOH (3.0 mL) and stirred with 5 equivalents of 4.0 M HCl in dioxane (3.0 mL) for 18 hrs. The reaction mixture was concentrated to give the title compound as a light yellow solid. MS (M+H)
[0155] Preparation 23
[0156] A solution of 50 mg of 3-aminopropionitrile and 596 mg of 2-aminothiophenol in EtOH (15 mL) was heated at reflux for six hrs. After cooling the solution to room temperature, the reaction was concentrated and the residue was purified by silica gel chromatography to afford the title compound as a red oil. MS (M+H)
[0157] Preparation 24
[0158] Step A
[0159] A solution of 250 mg of 2-chloro-5,6,7,8-tetrahydro-[1,6]naphthyridine (U.S. Pat. No. 6,169,093) in methylene chloride (6.1 mL) was treated with 0.148 mL of a 37% formalin solution, followed by 0.388 g of sodium triacetoxyborohydride. The reaction mixture was stirred at room temperature for 60 hrs. and quenched by the addition of 2N sodium hydroxide (6 mL). After stirring for 1 hr., the mixture was diluted with water and extracted with methylene chloride (2×). The organic layers were dried over sodium sulfate, filtered, and concentrated. Purification of the residue using silica gel chromatography provided N-methylchloronaphthyridine.
[0160] Step B
[0161] The product from Step A was dissolved in 10 equiv. of ethylenediamine and heated at 138° C. in a sealed tube for 18 hrs. The excess ethylenediamine was removed by distillation to provide the title compound as a brown oil. MS (M+H)
[0162] Preparation 25
[0163] A mixture of 500 mg of 2-aminoethanol and 328 mg of 60% sodium hydride-mineral oil dispersion in dioxane (27 mL) was heated to reflux for 30 min. After cooling to room temperature, 930 mg of 2-chloropyridine was added and the mixture was warmed to reflux and maintained at this temperature for 18 hrs. The reaction mixture was concentrated, diluted with water, and extracted with chloroform (3×). The organic extracts were washed with saturated brine, dried over sodium sulfate, filtered, concentrated, and the residue was purified by silica gel chromatography to give the title product as a yellow oily material. MS (M+H)
[0164] Preparation 26
[0165] Step A
[0166] A solution of 90 mg of 2-chloro-5,6,7,8-tetrahydro-[1,6]naphthyridine hydrochloride (U.S. Pat. No. 6,169,093), 0.134 g of N-carbobenzyloxyglycine, 0.130 g of triethylamine, and 0.087 g of 1-hydroxy-7-azabenzotriazole in DMF (2.7 mL) at 0° C. was stirred as 0.123 g (0.640 mmol) of EDC was added. After two hrs., the reaction mixture was poured into 4% magnesium sulfate solution, and the resulting solution was extracted with EtOAc and then methylene chloride. The organic extracts were dried over sodium sulfate, filtered, and concentrated to give an oil that solidified upon standing. Trituration with MeOH and collection of the solids provided the desired amide intermediate.
[0167] Step B
[0168] To a solution of 93 mg (0.260 mmol) of the product from Step A in a 3:2 THF/MeOH mixture (5 mL) was added 100 mg of 10% Pd/C and 300 mg of cyclohexene. This mixture was heated to reflux for 16 hrs., cooled to room temperature, and filtered through a short pad of diatomaceous earth. The solids were washed with methylene chloride, and the filtrate was concentrated to provide the title compound. MS (M+H)
[0169] Preparation 27
[0170] Step A
[0171] A solution of 0.90 g of 4-methylpiperazine, 0.830 g of chlorcacetonitrile, and 6.0 g of potassium carbonate in acetonitrile (9 mL) was stirred for 72 hrs. The reaction mixture was filtered and the filtrate was concentrated to provide a yellow solid.
[0172] Step B
[0173] The product from Step A was dissolved in a 1:1 mixture of ether/THF and was added to a suspension of 330 mg of LAH in ether (10 mL) at 0° C. The reaction was stirred at room temperature for 24 hrs., cooled to 0° C., and 5 mL of a solution of 6.0 N sodium hydroxide was added with stirring for 20 min. The solids were removed by filtration, and the filtrate was concentrated, dissolved in ether, dried over sodium sulfate, filtered, and concentrated to give the title compound as a light yellow oil. MS (M+H)
[0174] Preparation 28
[0175] Step A
[0176] A solution of 273 mg of methanesulfonic acid 2-benzyloxycarbonylamino-ethyl ester, 133 mg of 1,2,3,4-tetrahydroisoquinoline and 212 mg of sodium carbonate in DMF (3.0 mL) was heated to 90° C. for six hrs. The reaction mixture was cooled to room temperature, diluted with EtOAc, washed with water and saturated brine, dried over sodium sulfate, filtered, and concentrated. The residue was purified by silica gel chromatography to afford a yellow, oily product.
[0177] Step B
[0178] To a solution of 255 mg of the product from Step A in MeOH (3.0 mL) was added 99 mg of acetic acid, 102 mg of 10% Pd/C and 518 mg of ammonium formate. The mixture was refluxed for two hrs., cooled to room temperature, and filtered through a pad of diatomaceous earth. The filtrate was concentrated to give the title compound as a yellow oil. MS (M+H)
[0179] The following 1,2-diamines were prepared in a manner analogous to that described in Preparation 28 using appropriate starting materials.
MS Prep'n. Name (M + H) 29 N 164.9 diamine 30 2-(6,7-dimethoxy-3,4-dihydro-1H-isoquinolin- 237.2 2-yl)-ethylamine
[0180] Preparation 31
[0181] Step A
[0182] A solution of 315 mg of 2-chloroisonicotinic acid and 209 mg of morpholine in EtOAc (4.0 mL) was stirred as 1.27 g of a 50% solution of 1-propanephosphonic acid cyclic anhydride was added. This mixture was stirred at room temperature for six hrs. and another 1.27 g of the anhydride was added followed by stirring for another 18 hrs. The reaction was poured into saturated sodium bicarbonate solution and extracted with EtOAc (3×). The organic layers were dried over sodium sulfate, filtered, and concentrated to provide the morpholine amide.
[0183] Step B
[0184] A mixture of 220 mg of the product from Step A was heated with 467 mg of tert-butyl-N-(2-aminoethyl)carbamate at 125° C. for 18 hrs. Diisopropylethylamine (371 mg) was added and heating was continued for 48 hrs. The reaction mixture was cooled to room temperature and purified by silica gel chromatography to provide the desired intermediate.
[0185] Step C
[0186] A solution of 155 mg of the product from Step B in THF (1.5 mL) and 0.66 mL of a 1.0 M solution of LAH in THF was heated at reflux for five hrs. The reaction was cooled to 0° C. and quenched by the sequential addition of 25 μL of water, 25 μL of 3.0 N sodium hydroxide, 75 μL of water, and solid sodium sulfate. The solids were removed by filtration and the filtrate was concentrated to leave a residue that was purified by silica gel chromatography to provide an oily product.
[0187] Step D
[0188] A solution of 50 mg of the product from Step C was dissolved in 10 equiv. of a 4.0 M solution of HCl in dioxane. This mixture was stirred for 90 min. and then concentrated to give the title compound as the hydrochloride salt. MS (M+H)
[0189] The following 1,2-diamine was prepared in a manner analogous to that described in Preparation 31 using appropriate starting materials.
MS Prep'n. Name (M + H) 32 N 250.3 pyridin-2-yl]-ethane-1,2-diamine
[0190] Exemplary procedures for preparing the compounds of formula (I) according to Schemes 1-5 hereinabove are set forth in the following Examples.
[0191] To a solution of 0.10 g of 4-chloro-8-fluoro-1-methoxy-[1,2,4]triazolo[4,3-a]quinoxalin
e in DMF (1.3 mL) was added 0.144 g of 2-phenylethylamine. This solution was stirred at room temperature for 72 hrs., and then poured into cold water. The solid was dissolved in methylene chloride and washed with saturated brine, dried over sodium sulfate, filtered, and concentrated to provide 0.102 g of a light yellow solid. The solid was dissolved in a 1:1.5 mixture of 48% HBr/AcOH and was refluxed for two hrs. The reaction was concentrated and the residue was recrystallized from MeOH to provide the hydrobromide salt of the title compound as a yellow solid. MS (M+H)
[0192] The following compounds of formula (I) were prepared in a manner analogous to that described in Example 1 using appropriate starting materials.
MS (M + H) or Example Name (M − H) 2 8-fluoro-4-(2-naphthalen-1-yl-ethylamino)-2H- 372.0 (−) [1,2,4]triazolo[4,3-a]quinoxalin-1-one 3 8-fluoro-4-cyclohexylamino-2H-[1,2,4] 300.1 (−) triazolo[4,3-a]quinoxalin-1-one 4 4-[2-(4-chloro-phenyl)-ethylamino]-8-fluoro- 356.0 (−) 2H-[1,2,4]triazolo[4,3-a]quinoxalin-1-one 5 4-[2-(4-fluoro-phenyl)-ethylamino]-8-fluoro- 340.0 (−) 2H-[1,2,4]triazolo[4,3-a]quinoxalin-1-one 6 4-[2-(4-methyl-phenyl)-ethylamino]-8-fluoro- 336.0 (−) 2H-[1,2,4]triazolo[4,3-a]quinoxalin-1-one 7 8-fluoro-4-(2-pyridin-4-yl-ethylamino)-2H- 323.0 (−) [1,2,4]triazolo[4,3-a]quinoxalin-1-one 8 8-fluoro-4-(2-morpholin-4-yl-ethylamino)-2H- 331.1 (−) [1,2,4]triazolo[4,3-a]quinoxalin-1-one 9 8-fluoro-4-(4-phenyl-butylamino)-2H- 350.0 (−) [1,2,4]triazolo[4,3-a]quinoxalin-1-one 10 8-fluoro-4-(4-phenyl-propylamino)-2H- 336.0 (−) [1,2,4]triazolo[4,3-a]quinoxalin-1-one 11 8-fluoro-4-(2-pyridin-2-yl-ethylamino)-2H- 323.0 (−) [1,2,4]triazolo[4,3-a]quinoxalin-1-one 12 8-fluoro-4-[2-(1H-indol-3-yl)-ethylamino]-2H-[ 361.0 (−) 1,2,4]triazolo[4,3-a]quinoxalin-1-one 13 4-[2-(1H-benzoimidazol-2-yl)-ethylamino]-8- 362.0(−) fluoro-2H-[1,2,4]triazolo[4,3-a] quinoxalin-1-one 14 4-[2-(1H-benzoimidazol-2-yl)-propylamino]-8- 376.0 (−) fluoro-2H-[1,2,4]triazolo[4,3-a] quinoxalin-1-one 15 4-[2-(1H-benzoimidazol-2-yl)-methylamino]-8- 347.8 (−) fluoro-2H-[1,2,4]triazolo[4,3-a] quinoxalin-1-one 16 8-fluoro-4-{methyl-[2-(5-trifluoromethyl- 419.9 (−) pyridin-2-ylamino)-ethyl]-amino}-2H- [1,2,4]triazolo[4,3-a]quinoxalin-1-one 17 4-[2-(1H-benzoimidazol-2-yl)-butylamino]- 390.0 (−) 8-fluoro-2H-[1,2,4]triazolo[4,3-a] quinoxalin-1-one 18 8-fluoro-4-[2-(7-trifluoromethyl- 455.8 (−) quinolin-4-ylamino)-ethylamino]-2H- [1,2,4]triazolo[4,3-a]quinoxalin-1-one 19 4-[2-(1H-benzoimidazol-2-ylamino)- 377.0 (−) ethylamino]-8-fluoro-2H-[1,2,4] triazolo[4,3-a]quinoxalin-1-one 20 4-[2-(benzooxazol-2-ylamino)-ethylamino]-8- 377.9 (−) fluoro-2H-[1,2,4]triazolo[4,3-a] quinoxalin-1-one 21 4-[2-(1H-benzothiazol-2-ylamino)- 393.9 (−) ethylamino]-8-fluoro-2H-[1,2,4] triazolo[4,3-a]quinoxalin-1-one 22 8-fluoro-4-[2-(4-trifluoromethyl- 408.9 (+) pyrimidin-2-ylamino)-ethylamino]-2H- [1,2,4]triazolo[4,3-a]quinoxalin-1-one 23 N-[2-(8-fluoro-1-oxo-1,2,-dihydro[1,2,4] 303.0 (+) triazolo[4,3-a]quinoxalin-4-ylamino)-ethyl]- guanidine 24 8-fluoro-4-[2-(5-trifluoromethyl- 429.9 (−) 1H-benzoimidazol-2-yl)-ethylamino]- 2H-[1,2,4]triazolo[4,3-a]quinoxalin-1-one 25 8-fluoro-4-[2-(5-trifluoromethyl- 457.9 (−) 1H-benzoimidazol-2-yl)-butylamino]-2H- [1,2,4]triazolo[4,3-a]quinoxalin-1-one 26 8-fluoro-4-[2-(4-trifluoromethyl-pyridin-2- 421.9 (+) ylamino)-propylamino]-2H-[1,2,4]triazolo[ 4,3-a]quinoxalin-1-one 27 8-fluoro-4-[2-(4-methyl-piperazin-1-yl)- 344.0 (+) ethylamino]-2H-[1,2,4]triazolo [4,3-a]quinoxalin-1-one 28 8-fluoro-4-[2-(8-trifluoromethyl- 457.4 (+) quinolin-4-ylamino)-ethylamino]-2H- [1,2,4]triazolo[4,3-a]quinoxalin-1-one 29 8-fluoro-4-[2-(6-trifluoromethyl- 455.8 (−) quinolin-4-ylamino)-ethylamino]-2H- [1,2,4]triazolo[4,3-a]quinoxalin-1-one 30 8-fluoro-4-[2-(2-trifluoromethyl- 457.9 (+) quinolin-4-ylamino)-ethylamino]-2H- [1,2,4]triazolo[4,3-a]quinoxalin-1-one 31 4-[2-(6-chloro-benzothiazol-2-ylamino)- 427.8 (−) ethylamino]-8-fluoro-2H-[1,2,4] triazolo[4,3-a]quinoxalin-1-one 32 4-[2-(6-methoxy-benzothiazol-2-ylamino)- 423.9 (−) ethylamino]-8-fluoro-2H-[1,2,4] triazolo[4,3-a]quinoxalin-1-one 33 8-fluoro-4-[2-(1-methyl-piperidin-4- 358.3 (−) ylamino)-ethylamino]-2H-[1,2,4] triazolo[4,3-a]quinoxalin-1-one 34 8-fluoro-4-[2-(pyridin-2-ylamino)- 338.0 (−) ethylamino]-2H-[1,2,4]triazolo [4,3-a]quinoxalin-1-one 35 8-fluoro-4-[2-(quinolin-2-ylamino)- 387.9 (−) ethylamino]-2H-[1,2,4]triazolo [4,3-a]quinoxalin-1-one 36 4-(2-benzothiazol-2-yl-ethylamino)-8-fluoro-2H- 379.2 (−) [1,2,4]triazolo[4,3-a]quinoxalin-1-one 37 8-fluoro-4-[2-(pyridin-4-ylamino)-ethylamino]- 338.3 (−) 2H-[1,2,4]triazolo[4,3-a]quinoxalin-1-one 38 4-[2-(3,4-dihydro-1H-isoquinolin-2-yl)- 377.3 (−) ethylamino]-8-fluoro-2H-[1,2,4] triazolo[4,3-a]quinoxalin-1-one 39 4-[2-(7,8-dihydro-5H-[1,6]naphthyridin-6-yl)- 392.1 (−) 2-oxo-ethylamino]-8-fluoro-2H-[1,2,4]triazolo [4,3-a]quinoxalin-1-one 40 8-fluoro-4-[2-(6-methyl-5,6,7,8- 407.3 (−) tetrahydro-[1,6]naphthyridin-2-ylamino)- ethylamino]-2H-[1,2,4]triazolo [4,3-a]quinoxalin-1-one 41 8-fluoro-4-[2-(4-morpholin-4-ylmethyl-pyridin-2- 437.2 (−) ylamino)-ethylamino]-2H-[1,2,4]triazolo [4,3-a]quinoxalin-1-one 42 2-[2-(8-fluoro-1-oxo-1,2-dihydro[1,2,4] 384.3 (+) triazolo[4,3-a]quinoxalin-4-ylamino- ethylamino]-isonicotinic acid 43 4-[2-(6,7-dimethoxy-3,4-dihydro-1H-isoquinolin- 437.3 (−) 2-yl)-ethylamino]-8-fluoro-2H-[1,2,4 ]triazolo[4,3-a]quinoxalin-1-one 44 8-fluoro-4-[2-(methyl-pyridin-4-ylmethyl- 366.3 (−) amino)-ethylamino]-2H-[1,2,4] triazolo[4,3-a]quinoxalin-1-one 45 8-fluoro-4-(piperidin-4-ylamino)-2H- 301.0 (−) [1,2,4]triazolo[4,3-a]quinoxalin-1-one 46 8-bromo-4-isopropylamino-2H-[1,2,4] 324.2 (+) triazolo[4,3-a]quinoxalin-1-one 47 4-[2-(benzothiazol-2-ylamino)- 456.0 (+) ethylamino]-8-bromo-2H-[1,2,4] triazolo[4,3-a]quinoxalin-1-one 48 8-chloro-4-isopropylamino-2H-[1,2,4] 278.0 (+) triazolo[4,3-a]quinoxaline-1-one
[0193] To a solution of 500 mg of 4-chloro-8-fluoro-1-methoxy-[1,2,4]triazolo[4,3-a]quinoxalin
e in DMF (6.0 mL) was added 637 mg of benzylamine. This solution was stirred at room temperature for 18 hrs. and then diluted with EtOAc and washed with water and saturated lithium chloride. The extracts were dried over sodium sulfate, filtered, and concentrated and the residue was separated by silica gel chromatography to give a yellow solid. This material was dissolved in a 1:1.5 mixture of 48% HBr/AcOH, and refluxed for 12 hrs. The reaction mixture was concentrated and the residue was recrystallized from MeOH to afford the title compound as a yellow solid. MS (M+H)
[0194] To a solution of 50 mg of 4-chloro-8-bromo-1 -methoxy-[1,2,4]triazolo[4,3-a]quinoxaline in DMF (1.0 mL) was added 51 mg of tryptamine. This solution was stirred at room temperature for 18 hrs., and then diluted with EtOAc and washed with water and saturated brine. The extracts were dried over sodi