WO2012172449A1 - Lactams as beta secretase inhibitors - Google Patents

Abstract

Compound and pharmaceutically acceptable salts of the compound are disclosed, wherein the compound has the structure (I) as defined in the specification. Corresponding pharmaceutical compositions, methods of treatment, methods of synthesis, and intermediates are also disclosed. The compound of formula I is useful as beta secretase inhibitor for use in the treatment of Alzheimer's and other neurodegenerative and/or neurological disorders.

Description

LACTAMS AS BETA SECRETASE INHIBITORS

BACKGROUND OF THE INVENTION The present inventions relate to a small molecule inhibitor of β-site amyloid precursor protein (APP) Cleaving Enzyme 1 (BACE 1 ) and it's pharmaceutically acceptable salts. The invention also relates to processes for the preparation of, intermediates used in the preparation of, pharmaceutical compositions containing and the uses of the compound in the treating of Alzheimer's disease (AD) and other neurodegenerative and/or neurological disorders in mammals, including humans.

The present teachings also relate to inhibiting in mammals, including humans, the production of A-beta peptides that may contribute to the formation of neurological deposits of amyloid protein. Additionally, the present teachings relate to a spiro- piperidine compound useful in the treatment of neurodegenerative and/or neurological disorders, such as Alzheimer's disease and Down's Syndrome, related to A-beta peptide production.

The compound of the invention is, therefore, useful in the treatment of a wide range of disorders, particularly Alzheimer's disease (AD) and other neurodegenerative and/or neurological disorders (such as migraine; epilepsy; Alzheimer's disease;

Parkinson's disease; brain injury; stroke; cerebrovascular disease; cognitive disorder; sleep disorder). Other conditions that may be treated with the compound of the invention include: a psychiatric disorder (such as anxiety; factitious disorder; impulse control disorder; mood disorder; psychomotor disorder; psychotic disorder; drug dependence; eating disorder; and pediatric psychiatric disorder) in a mammal, including a human, comprising administering to said mammal a therapeutically effective amount of a compound of the invention or pharmaceutically acceptable salt thereof.

Numerous BACE inhibitors are currently undergoing human clinical evaluation such as SCH745966 (Merck/Scherring), JNJ-715754 (J&J), AMG-0683 (Amgen) and inhibiting ASP-1702 (CoMentis) to name but a few. There are no BACE compounds yet approved for the treatment of Alzheimer's disease. It is believed that the compound of the present invention has improved properties which are expected to differentiate the compound from those already known. Specifically, the compound of the invention possesses enhanced brain penetration and improved cardiovascular properties. The compound of the invention, further, has selectivity in vitro over other aspartyl proteases. Accordingly, there is a continuing need for new compounds that may be used to treat Alzheimer's disease (AD) and other neurodegenerative and/or neurological disorders in mammals, including humans.

SUMMARY OF THE INVENTION This present invention relates to the compound, 1 -(3-fluorophenyl)-8-(4-hydroxy-

3-(5-methyl-1 H-pyrazol-1 -yl)benzyl)-7-methyl-1 ,8-diazaspiro[4.5]dec-3-en-2-one having the structure:

or a pharmaceutically acceptable salt thereof.

As noted above, the compound of the invention may exist in the form of pharmaceutically acceptable salts such as, e.g., an acid addition salt of the compound of the invention. The phrase "pharmaceutically acceptable salt(s)", as used herein, unless otherwise indicated, includes salts of the compound of the invention which has basic functionality (e.g., piperdine nitrogen) and thus capable of forming a wide variety of salts with various inorganic and organic acids. The acids that may be used to prepare a pharmaceutically acceptable salt are those that form non-toxic acid addition salts, i.e., salts containing pharmacologically acceptable anions, such as the acetate, ascorbate, benzoate, bisulfate, bitartrate, citrate, acid citrate, formate, fumarate, gentisinate, gluconate, glucuronate, glutamate, hydrochloride, hydrobromide, hydroiodide, isonicotinate, lactate, maleate, nitrate, pantothenate, phosphate, acid phosphate, saccharate, salicylate, succinate, sulfate, tartrate, methanesulfonate, ethanesulfonate, benzenesulfonate, p-toluenesulfonate and pamoate [i.e., 1 , 1 '-methylene-bis-(2-hydroxy- 3-naphthoate)] salts. Examples of salts include, but are not limited to, acetate, acrylate,

benzenesulfonate, benzoate (such as chlorobenzoate, methylbenzoate, dinitrobenzoate, hydroxybenzoate, and methoxybenzoate), bicarbonate, bisulfate, bisulfite, bitartrate, borate, bromide, butyne-1 ,4-dioate, calcium edetate, camsylate, carbonate, chloride, caproate, caprylate, clavulanate, citrate, decanoate, dihydrochloride,

dihydrogenphosphate, edetate, edislyate, estolate, esylate, ethylsuccinate, formate, fumarate, gluceptate, gluconate, glutamate, glycollate, glycollylarsanilate, heptanoate, hexyne-1 ,6-dioate, hexylresorcinate, hydrabamine, hydrobromide, hydrochloride, γ- hydroxybutyrate, iodide, isobutyrate, isothionate, lactate, lactobionate, laurate, malate, maleate, malonate, mandelate, mesylate, metaphosphate, methane-sulfonate, methylsulfate, monohydrogenphosphate, mucate, napsylate, naphthalene-1 -sulfonate, naphthalene-2-sulfonate, nitrate, oleate, oxalate, pamoate (embonate), palmitate, pantothenate, phenylacetates, phenylbutyrate, phenylpropionate, phosphate, phthalate, phospate/diphosphate, polygalacturonate, propanesulfonate, propionate, propiolate, pyrophosphate, pyrosulfate, salicylate, stearate, subacetate, suberate, succinate, sulfate, sulfonate, sulfite, tannate, tartrate, teoclate, tosylate, triethiodode, and valerate salts.

For a review on suitable salts, see Handbook of Pharmaceutical Salts:

Properties, Selection, and Use by Stahl and Wermuth (Wiley-VCH, 2002). Methods for making pharmaceutically acceptable salts of the compound of the invention are known to one of skill in the art.

Salts of particular interest include acetate, citrate, phosphate, L(+) lactate, L(+) tartrate, succinate, benzenesulfonate, sulfonate, fumarate, hydrochloride, 4- toluenesulfonate and methylsulfate.

As used herein, the terms "the present invention," "compound of the invention" and "the present invention or pharmaceutically acceptable salts thereof" are defined to include all forms of the compound of the invention, including hydrates, solvates, isomers, crystalline and non-crystalline forms, isomorphs, polymorphs, metabolites, and prodrugs thereof.

The compounds of the invention may exist in a continuum of solid states ranging from fully amorphous to fully crystalline. The term 'amorphous' refers to a state in which the material lacks long range order at the molecular level and, depending upon temperature, may exhibit the physical properties of a solid or a liquid. Typically such materials do not give distinctive X-ray diffraction patterns and, while exhibiting the properties of a solid, are more formally described as a liquid. Upon heating, a change from solid to liquid properties occurs which is characterized by a change of state, typically second order ('glass transition'). The term 'crystalline' refers to a solid phase in which the material has a regular ordered internal structure at the molecular level and gives a distinctive X-ray diffraction pattern with defined peaks. Such materials when heated sufficiently will also exhibit the properties of a liquid, but the change from solid to liquid is characterized by a phase change, typically first order ('melting point').

The compound of Formula I may exist in unsolvated and solvated form. The term 'solvate' is used herein to describe a molecular complex comprising the compound of the invention and one or more pharmaceutically acceptable solvent molecules, for example, ethanol. The term 'hydrate' is employed when said solvent is water.

A currently accepted classification system for organic hydrates is one that defines isolated site, channel, or metal-ion coordinated hydrates - see Polymorphism in Pharmaceutical Solids by K. R. Morris (Ed. H. G. Brittain, Marcel Dekker, 1995). Isolated site hydrates are ones in which the water molecules are isolated from direct contact with each other by intervening organic molecules. In channel hydrates, the water molecules lie in lattice channels where they are next to other water molecules. In metal-ion coordinated hydrates, the water molecules are bonded to the metal ion.

When the solvent or water is tightly bound, the complex will have a well-defined stoichiometry independent of humidity. When, however, the solvent or water is weakly bound, as in channel solvates and hygroscopic compounds, the water/solvent content will be dependent on humidity and drying conditions. In such cases, non-stoichiometry will be the norm.

Also included within the scope of the invention are multi-component complexes (other than salts and solvates) wherein the drug and at least one other component are present in stoichiometric or non-stoichiometric amounts. Complexes of this type include clathrates (drug-host inclusion complexes) and co-crystals. The latter are typically defined as crystalline complexes of neutral molecular constituents which are bound together through non-covalent interactions, but could also be a complex of a neutral molecule with a salt. Co-crystals may be prepared by melt crystallization, by recrystallization from solvents, or by physically grinding the components together - see Chem Commun, 17, 1889-1896, by O. Almarsson and M. J. Zaworotko (2004). For a general review of multi-component complexes, see J Pharm Sci, 64 (8), 1269-1288, by Haleblian (August 1975).

Hereinafter all references to compounds of Formula I include references to the compound itself, and its salts, solvates, multi-component complexes and liquid crystals of salts thereof.

The compounds of the invention include compounds of Formula I as hereinbefore defined, including all polymorphs and crystal habits thereof, prodrugs and isomers thereof (including optical, geometric and tautomeric isomers) as hereinafter defined and isotopically-labeled compounds of Formula I.

The invention also relates to prodrugs of the compounds of Formula I. Thus certain derivatives of compounds of Formula I which may have little or no pharmacological activity themselves can, when administered into or onto the body, be converted into compounds of Formula I having the desired activity, for example, by hydrolytic cleavage. Such derivatives are referred to as "prodrugs". Further information on the use of prodrugs may be found in Pro-drugs as Novel Delivery Systems, Vol. 14, ACS Symposium Series (T. Higuchi and W. Stella) and Bioreversible Carriers in Drug Design, Pergamon Press, 1987 (Ed. E. B. Roche, American Pharmaceutical Association).

Prodrugs in accordance with the invention can, for example, be produced by replacing appropriate functionalities present in the compounds of Formula I with certain moieties known to those skilled in the art as 'pro-moieties' as described, for example, in Design of Prodrugs by H. Bundgaard (Elsevier, 1985).

Some non-limiting examples of prodrugs in accordance with the invention include the compound of Formula I which contains an alcohol functionality which is functionalized into a suitably metabolically labile group (ethers, esters, carbamates, acetals, ketals, etc.).

Further examples of replacement groups in accordance with the foregoing examples and examples of other prodrug types may be found in the aforementioned references.

Moreover, the compounds of Formula I may themselves act as prodrugs of other compounds of Formula I.

Also included within the scope of the invention are metabolites of compounds of Formula I, that is, compounds formed in vivo upon administration of the drug. The compound of the invention has asymmetric carbon atoms (see the compound of Formula la). The carbon-carbon bonds of the compound of the invention can be depicted herein using a solid line ( ), a solid wedge ( ""^- ), or a dotted wedge ( ¹¹¹ ). The use of a solid line to depict bonds to asymmetric carbon atoms is meant to indicate that all possible stereoisomers (e.g. specific enantiomers, racemic mixtures, etc.) at that carbon atom are included. The use of either a solid or dotted wedge to depict bonds to asymmetric carbon atoms is meant to indicate that only the stereoisomer shown is meant to be included. It is possible that the compound of the invention may contain more than one asymmetric carbon atom. In those compounds, the use of a solid line to depict bonds to asymmetric carbon atoms is meant to indicate that all possible stereoisomers are meant to be included. For example, unless stated otherwise, it is intended that the compound of the invention may exist as enantiomers and diastereomers or as racemates and mixtures thereof. The use of a solid line to depict bonds to one or more asymmetric carbon atoms in a compound of the invention and the use of a solid or dotted wedge to depict bonds to other asymmetric carbon atoms in the same compound is meant to indicate that a mixture of diastereomers is present.

Stereoisomers of the invention include cis and trans isomers, optical isomers such as R and S enantiomers, diastereomers, geometric isomers, rotational isomers, conformational isomers, and tautomers of the compound of the invention, including compounds exhibiting more than one type of isomerism; and mixtures thereof (such as racemates and diastereomeric pairs). Also included are acid additions or base addition salts wherein the counterion is optically active, for example, d-lactate or l-lysine, or racemic, for example, dl-tartrate or dl-arginine.

When any racemate crystallizes, crystals of two different types are possible. The first type is the racemic compound (true racemate) referred to above wherein one homogeneous form of crystal is produced containing both enantiomers in equimolar amounts. The second type is the racemic mixture or conglomerate wherein two forms of crystal are produced in equimolar amounts each comprising a single enantiomer.

The present invention also includes isotopically-labeled compounds, which are identical to that recited in the invention above, 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 may be incorporated into the compound of the invention include isotopes of hydrogen, carbon, nitrogen, oxygen, phosphorus, fluorine and chlorine, such as, but not limited to,

²H, ³H, ¹³C, ¹⁴C, ¹⁵N, ¹⁸0, ¹⁷0, ³¹ P, ³²P, ³⁵S, ¹⁸F, and ³⁶CI. Certain isotopically-labeled compounds of the invention, for example those into which radioactive isotopes such as ³H and ¹⁴C are incorporated, are useful in drug and/or substrate tissue distribution assays. Tritiated, i.e., ³H, and carbon-14, i.e., ¹⁴C, isotopes are particularly preferred for their ease of preparation and detect ability. Further, substitution with heavier isotopes such as deuterium, i.e., ²H, may afford certain therapeutic advantages resulting from greater metabolic stability, for example increased in vivo half-life or reduced dosage requirements and, hence, may be preferred in some circumstances. Isotopically-labeled compounds of the invention may generally be prepared by carrying out the procedures disclosed in the Schemes and/or in the Examples and Preparations below, by substituting an isotopically-labeled reagent for a non-isotopically-labeled reagent.

An embodiment of the invention is a compound of the Formula la:

la wherein the stereochemistry shown in Formula la is the absolute stereochemistry, or a pharmaceutically acceptable salt thereof.

Another embodiment of the invention is a compound of the Formula lb:

lb wherein the stereochemistry shown in Formula lb is the absolute stereochemistry, or a pharmaceutically acceptable salt thereof.

Another embodiment of the invention is a compound of the Formula Ic:

Ic wherein the stereochemistry shown in Formula Ic is the absolute stereochemistry, or a pharmaceutically acceptable salt thereof.

Another embodiment of the invention is a compound of the Formula Id:

Id wherein the stereochemistry shown in Formula Id is the absolute stereochemistry, or a pharmaceutically acceptable salt thereof.

In yet another embodiment of the invention is a hydrochloride salt of the compound of Formula I (or la, lb, Ic, or Id).

Another embodiment of the invention is a hydrochloride monohydrate salt of the compound of Formula I (or la, lb, Ic, or Id).

Another embodiment of the invention is a crystalline polymorph of a hydrochloride monohydrate salt of the compound of Formula la with X-ray diffraction 2- Theta reflections of about 8.3, 12.1 and 14.4. Another embodiment of the invention is a crystalline polymorph of a hydrochloride monohydrate salt of the compound of Formula la with additional X-ray diffraction 2-Theta reflections of about 8.3.

Another embodiment of the invention is a crystalline polymorph of a hydrochloride monohydrate salt of the compound of Formula la with additional X-ray diffraction 2-Theta reflections of about 12.1 .

Another embodiment of the invention is a crystalline polymorph of a hydrochloride monohydrate salt of the compound of Formula la with additional X-ray diffraction 2-Theta reflections of about 14.4.

Another embodiment of the invention is a fumarate salt of the compound of

Formula I (or la, lb, lc, or Id).

Another embodiment of the invention is an anhydrous fumarate salt of the compound of Formula I (or la, lb, lc, or Id).

Another embodiment of the invention is a crystalline polymorph of anhydrous fumarate salt of the compound of Formula la.

Another embodiment of the invention is a crystalline polymorph of anhydrous fumarate salt of the compound of Formula la with X-ray diffraction 2-Theta reflections of about 9.7, 10.9 and 15.9.

Another embodiment of the invention is a crystalline polymorph of anhydrous fumarate salt of the compound of Formula la with additional X-ray diffraction 2-Theta reflections of about 9.7.

Another embodiment of the invention is a crystalline polymorph of anhydrous fumarate salt of the compound of Formula la with additional X-ray diffraction 2-Theta reflections of about 10.9.

Another embodiment of the invention is a crystalline polymorph of anhydrous fumarate salt of the compound of Formula la with additional X-ray diffraction 2-Theta reflections of about 15.9.

In another embodiment, there is provided a method for the treatment of a disease or condition selected from the group consisting of neurological and psychiatric disorders comprising administering to the mammal an effective amount of the compound of Formula I or pharmaceutically acceptable salt thereof.

Another embodiment provides for a method for the treatment of a neurological disorder, wherein the neurological disorder is migraine, epilepsy, Alzheimer's disease, Parkinson's disease, brain injury, stroke, cerebrovascular diseases, cerebral arteriosclerosis, cerebral amyloid angiopathy, hereditary cerebral hemorrhage, brain hypoxia-ischemia, cognitive disorders, amnesia, senile dementia, HIV associated dementia, Alzheimer's disease, Huntington's disease, Lewy body dementia, vascular dementia, drug related dementia, tardive dyskinesia, myoclonus, dystonia, delirium, Pick's disease, Creutzfeldt-Jacob disease, HIV disease, Gilles de la Tourette's syndrome, epilepsy, muscular spasms and disorders associated with muscular spasticity or weakness, tremors, mild cognitive impairment); mental deficiency, spasticity, Down syndrome, fragile X syndrome, sleep disorders, hypersomnia, circadian rhythm sleep disorder, insomnia, parasomnia and sleep deprivation.

Another embodiment provides for a method for the treatment of psychiatric disorder, wherein the psychiatric disorder is anxiety, acute stress disorder, generalized anxiety disorder, social anxiety disorder, panic disorder, post-traumatic stress disorder, agoraphobia, obsessive-compulsive disorder, factitious disorder, acute hallucinatory mania, impulse control disorders, compulsive gambling, intermittent explosive disorder, mood disorders, bipolar I disorder, bipolar II disorder, mania, mixed affective state, major depression, chronic depression, seasonal depression, psychotic depression, seasonal depression, premenstrual syndrome (PMS) premenstrual dysphoric disorder (PDD), postpartum depression, psychomotor disorder, psychotic disorders, schizophrenia, schizoaffective disorder, schizophreniform, delusional disorder, drug dependence, narcotic dependence, alcoholism, amphetamine dependence, cocaine addiction, nicotine dependence, drug withdrawal syndrome, eating disorders, anorexia, bulimia, binge eating disorder, hyperphagia, obesity, compulsive eating disorders, pagophagia, sexual dysfunction disorders, urinary incontinence, neuronal damage disorders, ocular damage, retinopathy or macular degeneration of the eye, tinnitus, hearing impairment and loss, brain edema, pediatric psychiatric disorders, attention deficit disorder, attention deficit/hyperactive disorder, conduct disorder and autism.

In another embodiment, there is provided a pharmaceutical composition comprising a compound of the Formula I or a pharmaceutically acceptable salt thereof and a pharmaceutically acceptable carrier.

In another embodiment, there is provided an atypical antipsychotic, a

cholinesterase inhibitor, dimebon or NMDA receptor antagonist.

The compound of the invention and the pharmaceutically acceptable salts thereof are useful for the treatment of a variety of neurological and psychiatric disorders, including: acute neurological and psychiatric disorders such as cerebral deficits subsequent to cardiac bypass surgery and grafting, stroke, cerebral ischemia, spinal cord trauma, head trauma, perinatal hypoxia, cardiac arrest, hypoglycemic neuronal damage, dementia (including AIDS-induced dementia), Alzheimer's disease,

Huntington's Chorea, amyotrophic lateral sclerosis, ocular damage, retinopathy, cognitive disorders, idiopathic and drug- induced Parkinson's disease, muscular spasms and disorders associated with muscular spasticity including tremors, epilepsy, convulsions, migraine (including migraine headache), urinary incontinence, substance tolerance, substance withdrawal (including, substances such as opiates, nicotine, tobacco products, alcohol, benzodiazepines, cocaine, sedatives, hypnotics, etc.), psychosis, schizophrenia, anxiety (including generalized anxiety disorder, social anxiety disorder, panic disorder, post-traumatic stress disorder and obsessive compulsive disorder), mood disorders (including depression, mania, bipolar disorders), trigeminal neuralgia, hearing loss, tinnitus, macular degeneration of the eye, emesis, brain edema, pain (including acute and chronic pain states, severe pain, intractable pain, neuropathic pain, and post-traumatic pain), tardive dyskinesia, sleep disorders (including

narcolepsy), attention deficit/hyperactivity disorder, attention deficit disorder, and conduct disorder. Accordingly, in one embodiment, the invention provides a method for treating a condition in a mammal, such as a human, selected from the conditions above, comprising administering a therapeutically effective amount of a compound of the invention or a pharmaceutically acceptable salt thereof to the mammal. The mammal may be a mammal in need of such treatment or prevention.

As used herein, the phrase "therapeutically effective amount" refers to the amount of active compound or pharmaceutical agent that is effective to treat the condition of interest - i.e., the amount of active compound or pharmaceutical agent that is effective to elicit a biological or medicinal response in a tissue, system, animal, individual or human that is being sought by a researcher, veterinarian, medical doctor or other clinician, which includes one or more of the following:

(1 ) preventing the disease; for example, preventing a disease, condition or disorder in an individual that may be predisposed to the disease, condition or disorder but does not yet experience or display the pathology or symptomatology of the disease;

(2) inhibiting the disease; for example, inhibiting a disease, condition or disorder in an individual that is experiencing or displaying the pathology or symptomatology of the disease, condition or disorder (i.e., arresting or slowing further development of the pathology and/or symptomatology); and (3) ameliorating the disease; for example, ameliorating a disease, condition or disorder in an individual that is experiencing or displaying the pathology or symptomatology of the disease, condition or disorder (i.e., reversing the pathology and/or symptomatology).

The term "treating", as used herein, unless otherwise indicated, means reversing, alleviating, inhibiting the progress of, or preventing the disorder or condition to which such term applies, or one or more symptoms of such disorder or condition. The term "treatment", as used herein, unless otherwise indicated, refers to the act of treating a mammal. The term "treating" also includes adjuvant and neo-adjuvant treatment of a subject.

Administration of the compound of the invention may be effected by any method that enables delivery of the compound to the site of action. These methods include oral routes, intraduodenal routes, parenteral injection (including intravenous, subcutaneous, intramuscular, intravascular and infusion), topical, and rectal administration.

Dosage regimens may be adjusted to provide the optimum desired response. For example, a single bolus may be administered, several divided doses may be

administered over time or the dose may be proportionally reduced or increased as indicated by the exigencies of the therapeutic situation. It is especially advantageous to formulate parenteral compositions in dosage unit form for ease of administration and uniformity of dosage. Dosage unit form, as used herein, refers to physically discrete units suited as unitary dosages for the mammalian subjects to be treated; each unit containing a predetermined quantity of active compound calculated to produce the desired therapeutic effect in association with the required pharmaceutical carrier.

Thus, the skilled artisan would appreciate, based upon the disclosure provided herein, that the dose and dosing regimen is adjusted in accordance with methods well- known in the therapeutic arts. That is, the maximum tolerable dose can be readily established, and the effective amount providing a detectable therapeutic benefit to a patient may also be determined, as can the temporal requirements for administering each agent to provide a detectable therapeutic benefit to the patient. Accordingly, while certain dose and administration regimens are exemplified herein, these examples in no way limit the dose and administration regimen that may be provided to a patient in practicing the present invention.

It is to be noted that dosage values may vary with the type and severity of the condition to be alleviated, and may include single or multiple doses. It is to be further understood that for any particular subject, specific dosage regimens should be adjusted over time according to the individual need and the professional judgment of the person administering or supervising the administration of the compositions, and that dosage ranges set forth herein are exemplary only and are not intended to limit the scope or practice of the claimed composition. For example, doses may be adjusted based on pharmacokinetic or pharmacodynamic parameters, which may include clinical effects such as toxic effects and/or laboratory values. Thus, the present invention

encompasses intra-patient dose-escalation as determined by the skilled artisan.

Determining appropriate dosages and regimens for administration of the active agent are well-known in the relevant art and would be understood to be encompassed by the skilled artisan once provided the teachings disclosed herein.

The amount of the compound of the invention administered will be dependent on the subject being treated, the severity of the disorder or condition, the rate of administration, the disposition of the compound and the discretion of the prescribing physician. However, an effective dosage is in the range of about 0.001 to about 100 mg per kg body weight per day, preferably about 1 to about 35 mg/kg/day, in single or divided doses. For a 70 kg human, this would amount to about 25 mg/day to about 525 mg/day, preferably about 10 mg/day to about 250 mg/day. In some instances, dosage levels below the lower limit of the aforesaid range may be more than adequate, while in other cases still larger doses may be employed without causing any harmful side effect, provided that such larger doses are first divided into several small doses for

administration throughout the day.

As used herein, the term "combination therapy" refers to the administration of a compound of the invention together with an at least one additional pharmaceutical or medicinal agent, either sequentially or simultaneously.

Additionally, the present invention may include the use of a combination of a beta amyloid production inhibitor compound as provided in Formula (I) and one or more additional pharmaceutically active agent(s). If a combination of active agents is administered, then they may be administered sequentially or simultaneously, in separate dosage forms or combined in a single dosage form. Accordingly, the present invention also includes pharmaceutical compositions comprising an amount of: (a) a first agent comprising a compound of Formula (I) or a pharmaceutically acceptable salt of the compound; (b) a second pharmaceutically active agent; and (c) a pharmaceutically acceptable carrier, vehicle or diluent. Various pharmaceutically active agents may be selected for use in conjunction with the compound of the present invention, depending on the disease, disorder, or condition to be treated. Pharmaceutically active agents that may be used in combination with the compositions of the present invention include, without limitation:

(i) acetylcholinesterase inhibitors, such as donepezil hydrochloride (ARICEPT,

MEMAC), physostigmine salicylate (ANTILIRIUM), physostigmine sulfate (ESERINE), metrifonate, neostigmine, ganstigmine, pyridostigmine (MESTINON), ambenonium (MYTELASE), demarcarium, Debio 9902 (also known as ZT-1 ; Debiopharm), rivastigmine (EXELON), ladostigil, NP-0361 , galantamine hydrobromide (RAZADYNE, RIMINYL, NIVALIN), tacrine (COGNEX), tolserine, velnacrine maleate, memoquin, huperzine A (HUP-A; NeuroHitech), phenserine, edrophonium (ENLON, TENSILON), and INM-176;

(ii) amyloid-β (or fragments thereof), such as Αβ_1-15 conjugated to pan HLA DR- binding epitope (PADRE), ACC-001 (Elan/Wyeth), ACI-01 , ACI-24, AN-1792, Affitope AD-01 , CAD106, and V-950;

(iii) antibodies to amyloid-β (or fragments thereof), such as ponezumab, solanezumab, bapineuzumab (also known as AAB-001 ), AAB-002 (Wyeth/Elan), ACI-01 - Ab7, BAN-2401 , intravenous Ig (GAMMAGARD), LY2062430 (humanized m266; Lilly), R1450 (Roche), ACU-5A5, huC091 , and those disclosed in International Patent

Publication Nos WO04/032868, WO05/025616, WO06/036291 , WO06/069081 ,

WO06/1 18959, in US Patent Publication Nos US2003/0073655, US2004/0192898, US2005/0048049, US2005/0019328, in European Patent Publication Nos EP0994728 and 1257584, and in US Patent No 5,750,349;

(iv) amyloid-lowering or -inhibiting agents (including those that reduce amyloid production, accumulation and fibrillization) such as dimebon, davunetide, eprodisate, leuprolide, SK-PC-B70M, celecoxib, lovastatin, anapsos, oxiracetam, pramiracetam, varenicline, nicergoline, colostrinin, bisnorcymserine (also known as BNC), NIC5-15 (Humanetics), E-2012 (Eisai), pioglitazone, clioquinol (also known as PBT1 ), PBT2 (Prana Biotechnology), flurbiprofen (ANSAID, FROBEN) and its f?-enantiomer tarenflurbil (FLURIZAN), nitroflurbiprofen, fenoprofen (FENOPRON, NALFON), ibuprofen (ADVIL, MOTRIN, NUROFEN), ibuprofen lysinate, meclofenamic acid, meclofenamate sodium (MECLOMEN), indomethacin (INDOCIN), diclofenac sodium (VOLTAREN), diclofenac potassium, sulindac (CLINORIL), sulindac sulfide, diflunisal (DOLOBID), naproxen (NAPROSYN), naproxen sodium (ANAPROX, ALEVE), ARC031 (Archer Pharmaceuticals), CAD-106 (Cytos), LY450139 (Lilly), insulin-degrading enzyme (also known as insulysin), the gingko biloba extract EGb-761 (ROKAN, TEBONIN), tramiprosate (CEREBRIL, ALZHEMED), eprodisate (FIBRILLEX, KIACTA), compound W (3,5-bis(4-nitrophenoxy)benzoic acid), NGX-96992, neprilysin (also known as neutral endopeptidase (NEP)), scyllo-inositol (also known as scyllitol), atorvastatin (LIPITOR), simvastatin (ZOCOR), KLVFF-(EEX)3, SKF-74652, ibutamoren mesylate, BACE inhibitors such as ASP-1702, SCH-745966, JNJ-715754, AMG-0683, AZ-12304146, BMS-782450, GSK-188909, NB-533, E2609 and TTP-854; Gamma Secretase

Modulators such as ELND-007; and RAGE (receptor for advanced glycation end- products) inhibitors, such as TTP488 (Transtech) and TTP4000 (Transtech), and those disclosed in US Patent No 7,285,293, including PTI-777;

(v) alpha-adrenergic receptor agonists, such as guanfacine (INTUNIV, TENEX), clonidine (CATAPRES), metaraminol (ARAMI NE), methyldopa (ALDOMET, DOPAMET, NOVOMEDOPA), tizanidine (ZANAFLEX), phenylephrine (also known as

neosynephrine), methoxamine, cirazoline, guanfacine (INTUNIV), lofexidine, xylazine, modafinil (PROVIGIL), adrafinil, and armodafinil (NUVIGIL);

(vi) beta-adrenergic receptor blocking agents (beta blockers), such as carteolol, esmolol (BREVIBLOC), labetalol (NORMODYNE, TRANDATE), oxprenolol (LARACOR, TRASACOR), pindolol (VISKEN), propanolol (INDERAL), sotalol (BETAPACE,

SOTALEX, SOTACOR), timolol (BLOCADREN, TIMOPTIC), acebutolol (SECTRAL,

PRENT), nadolol (CORGARD), metoprolol tartrate (LOPRESSOR), metoprolol succinate (TOPROL-XL), atenolol (TENORMIN), butoxamine, and SR 59230A (Sanofi);

(vii) anticholinergics, such as amitriptyline (ELAVIL, ENDEP), butriptyline, benztropine mesylate (COGENTIN), trihexyphenidyl (ARTANE), diphenhydramine (BENADRYL), orphenadrine (NORFLEX), hyoscyamine, atropine (ATROPEN), scopolamine (TRANSDERM-SCOP), scopolamine methylbromide (PARMINE), dicycloverine (BENTYL, BYCLOMINE, DIBENT, DILOMINE), tolterodine (DETROL), oxybutynin (DITROPAN, LYRINEL XL, OXYTROL), penthienate bromide, propantheline (PRO-BANTHINE), cyclizine, imipramine hydrochloride (TOFRANIL), imipramine maleate (SURMONTIL), lofepramine, desipramine (NORPRAMIN), doxepin

(SINEQUAN, ZONALON), trimipramine (SURMONTIL), and glycopyrrolate (ROBINUL);

(viii) anticonvulsants, such as carbamazepine (TEGRETOL, CARBATROL), oxcarbazepine (TRILEPTAL), phenytoin sodium (PHENYTEK), fosphenytoin

(CEREBYX, PRODILANTIN), divalproex sodium (DEPAKOTE), gabapentin (NEURONTIN), pregabalin (LYRICA), topirimate (TOPAMAX), valproic acid

(DEPAKENE), valproate sodium (DEPACON), 1 -benzyl-5-bromouracil, progabide, beclamide, zonisamide (TRERIEF, EXCEGRAN), CP-465022, retigabine, talampanel, and primidone (MYSOLINE);

(ix) antipsychotics, such as lurasidone (LATUDA, also known as SM-13496;

Dainippon Sumitomo), aripiprazole (ABILIFY), chlorpromazine (THORAZINE), haloperidol (HALDOL), iloperidone (FANAPTA), flupentixol decanoate (DEPIXOL, FLUANXOL), reserpine (SERPLAN), pimozide (ORAP), fluphenazine decanoate, fluphenazine hydrochloride, prochlorperazine (COMPRO), asenapine (SAPHRIS), loxapine (LOXITANE), molindone (MOBAN), perphenazine, thioridazine, thiothixine, trifluoperazine (STELAZINE), ramelteon, clozapine (CLOZARIL), norclozapine (ACP- 104), risperidone (RISPERDAL), paliperidone (INVEGA), melperone, olanzapine (ZYPREXA), quetiapine (SEROQUEL), talnetant, amisulpride, ziprasidone (GEODON), blonanserin (LONASEN), and ACP-103 (Acadia Pharmaceuticals);

(x) calcium channel blockers such as lomerizine, ziconotide, nilvadipine

(ESCOR, NIVADIL), diperdipine, amiodipine (NORVASC, ISTIN, AMLODIN), felodipine (PLENDIL), nicardipine (CARDENE), nifedipine (ADALAT, PROCARDIA), MEM 1003 and its parent compound nimodipine (NIMOTOP), nisoldipine (SULAR), nitrendipine, lacidipine (LACIPIL, MOTENS), lercanidipine (ZANIDIP), lifarizine, diltiazem

(CARDIZEM), verapamil (CALAN, VERELAN), AR-R 18565 (AstraZeneca), and enecadin;

(xi) catechol O-methyltransferase (COMT) inhibitors, such as nitecapone, tolcapone (TASMAR), entacapone (COMTAN), and tropolone;

(xii) central nervous system stimulants, such as atomoxetine, reboxetine, yohimbine, caffeine, phenmetrazine, phendimetrazine, pemoline, fencamfamine

(GLUCOENERGAN, REACTIVAN), fenethylline (CAPTAGON), pipradol (MERETRAN), deanol (also known as dimethylaminoethanol), methylphenidate (DAYTRANA), methylphenidate hydrochloride (RITALIN), dexmethylphenidate (FOCALIN), amphetamine (alone or in combination with other CNS stimulants, e.g. ADDERALL (amphetamine aspartate, amphetamine sulfate, dextroamphetamine saccharate, and dextroamphetamine sulfate)), dextroamphetamine sulfate (DEXEDRINE,

DEXTROSTAT), methamphetamine (DESOXYN), lisdexamfetamine (VYVANSE), and benzphetamine (DIDREX); (xiii) corticosteroids, such as prednisone (STERAPRED, DELTASONE), prednisolone (PRELONE), predisolone acetate (OMNIPRED, PRED MILD, PRED FORTE), prednisolone sodum phosphate (ORAPRED ODT), methylprednisolone (MEDROL); methylprednisolone acetate (DEPO-MEDROL), and methylprednisolone sodium succinate (A-METHAPRED, SOLU-MEDROL);

(xiv) dopamine receptor agonists, such as apomorphine (APOKYN),

bromocriptine (PARLODEL), cabergoline (DOSTINEX), dihydrexidine,

dihydroergocryptine, fenoldopam (CORLOPAM), lisuride (DOPERGIN), terguride spergolide (PERMAX), piribedil (TRIVASTAL, TRASTAL), pramipexole (MIRAPEX), quinpirole, ropinirole (REQUIP), rotigotine (NEUPRO), SKF-82958 (GlaxoSmithKline), cariprazine, pardoprunox and sarizotan;

(xv) dopamine receptor antagonists, such as chlorpromazine, fluphenazine, haloperidol, loxzpine, resperidone, thioridazine, thiothixene, trifluoperazine,

tetrabenazine (NITOMAN, XENAZINE), 7-hydroxyamoxapine, droperidol (INAPSINE, DRIDOL, DROPLETAN), domperidone (MOTILIUM), L-741742, L-745870, raclopride, SB-27701 1A, SCH-23390, ecopipam, SKF-83566, and metoclopramide (REGLAN);

(xvi) dopamine reuptake inhibitors such as bupropion, safinamide, nomifensine maleate (MERITAL), vanoxerine (also known as GBR-12909) and its decanoate ester DBL-583, and amineptine;

(xvii) gamma-amino-butyric acid (GABA) receptor agonists, such as baclofen

(LIORESAL, KEMSTRO), siclofen, pentobarbital (NEMBUTAL), progabide (GABRENE), and clomethiazole;

(xviii) histamine 3 (H3) antagonists such as ciproxifan, tiprolisant, S-38093, irdabisant, pitolisant, GSK-239512, GSK-207040, JNJ-5207852, JNJ-17216498, HPP- 404, SAR-1 10894, trans-3-fluoro-3-(3-fluoro-4-pyrrolidin-1-ylmethyl-phenyl)-cyclobutane carboxylic acid ethylamide and those disclosed in US Patent Publication Nos US2005- 0043354, US2005-0267095, US2005-0256135, US2008-0096955, US2007-1079175, and US2008-0176925; International Patent Publication Nos WO2006/136924,

WO2007/063385, WO2007/069053, WO2007/088450, WO2007/099423,

WO2007/105053, WO2007/138431 , and WO2007/088462; and US Patent No

7, 1 15,600);

(xix) immunomodulators such as glatiramer acetate (also known as copolymer-1 ; COPAXONE), MBP-8298 (synthetic myelin basic protein peptide), dimethyl fumarate, fingolimod (also known as FTY720), roquinimex (LINOMIDE), laquinimod (also known as ABR-215062 and SAIK-MS), ABT-874 (human anti-IL-12 antibody; Abbott), rituximab (RITUXAN), alemtuzumab (CAMPATH), daclizumab (ZENAPAX), and natalizumab (TYSABRI);

(xx) immunosuppressants such as methotrexate (TREXALL, RHEUMATREX), mitoxantrone (NOVANTRONE), mycophenolate mofetil (CELLCEPT), mycophenolate sodium (MYFORTIC), azathioprine (AZASAN, IMURAN), mercaptopurine (PURI- NETHOL), cyclophosphamide (NEOSAR, CYTOXAN), chlorambucil (LEUKERAN), cladribine (LEUSTATIN, MYLINAX), alpha-fetoprotein, etanercept (ENBREL), and 4- benzyloxy-5-((5-undecyl-2H-pyrrol-2-ylidene)methyl)-2,2'-bi-1 H-pyrrole (also known as PNU-156804);

(xxi) interferons, including interferon beta-1 a (AVONEX, REBIF) and interferon beta-1 b (BETASERON, BETAFERON);

(xxii) levodopa (or its methyl or ethyl ester), alone or in combination with a DOPA decarboxylase inhibitor (e.g. carbidopa (SINEMET, CARBILEV, PARCOPA), benserazide (MADOPAR), omethyldopa, monofluromethyldopa, difluoromethyldopa, brocresine, or m-hydroxybenzylhydrazine);

(xxiii) /V-methyl-D-aspartate (NMDA) receptor antagonists, such as memantine (NAMENDA, AXURA, EBIXA), amantadine (SYMMETREL), acamprosate (CAMPRAL), besonprodil, ketamine (KETALAR), delucemine, dexanabinol, dexefaroxan,

dextromethorphan, dextrorphan, traxoprodil, CP-283097, himantane, idantadol, ipenoxazone, L-701252 (Merck), lancicemine, levorphanol (DROMORAN), LY-233536 and LY-235959 (both Lilly), methadone, (DOLOPHINE), neramexane, perzinfotel, phencyclidine, tianeptine (STABLON), dizocilpine (also known as MK-801 ), EAB-318 (Wyeth), ibogaine, voacangine, tiletamine, riluzole (RILUTEK), aptiganel (CERESOTAT), gavestinel, and remacimide;

(xxiv) monoamine oxidase (MAO) inhibitors, such as selegiline (EMSAM), selegiline hydrochloride (l-deprenyl, ELDEPRYL, ZELAPAR), dimethylselegilene, brofaromine, phenelzine (NARDIL), tranylcypromine (PARNATE), moclobemide

(AURORIX, MANERIX), befloxatone, safinamide, isocarboxazid (MARPLAN), nialamide (NIAMID), rasagiline (AZILECT), iproniazide (MARSILID, IPROZID, IPRONID), CHF- 3381 (Chiesi Farmaceutici), iproclozide, toloxatone (HUMORYL, PERENUM), bifemelane, desoxypeganine, harmine (also known as telepathine or banasterine), harmaline, linezolid (ZYVOX, ZYVOXID), and pargyline (EUDATIN, SUPIRDYL); (xxv) muscarinic receptor (particularly M1 subtype) agonists, such as cevimeline, levetiracetam, bethanechol chloride (DUVOID, URECHOLINE), itameline, pilocarpine (SALAGEN), NGX267, arecoline, L-687306 (Merck), L-689660 (Merck), furtrethonium iodide (FURAMON, FURANOL), furtrethonium benzensulfonate, furtrethonium p- toluenesulfonate, McN-A-343, oxotremorine, sabcomeline, AC-90222 (Acadia

Pharmaceuticals), and carbachol (CARBASTAT, MIOSTAT, CARBOPTIC);

(xxvi) neuroprotective drugs such as bosutinib, condoliase, airmoclomol, lamotrigine, perampanel, aniracetam, minaprime, viluzole 2,3,4,9-tetrahydro-1 H- carbazol-3-one oxime, desmoteplase, anatibant, astaxanthin, neuropeptide NAP (e.g. AL-108 and AL-208; both Allon Therapeutics), neurostrol, perampenel, ispronicline, bis(4-3-D-glucopyranosyloxybenzyl)-2-3-D-glucopyranosyl-2-isobutyltartrate (also known as dactylorhin B or DHB), formobactin, xaliproden (XAPRILA), lactacystin, dimeboline hydrochloride (DIMEBON), disufenton (CEROVIVE), arundic acid (ONO-2506,

PROGLIA, CEREACT), citicoline (also known as cytidine 5'-diphosphocholine), edaravone (RADICUT), AEOL-101 13 and AEOL-10150 (both Aeolus Pharmaceuticals), AGY-94806 (also known as SA-450 and Msc-1 ), granulocyte-colony stimulating factor (also known as AX-200), BAY-38-7271 (also known as KN-387271 ; Bayer AG), ancrod (VIPRINEX, ARWIN), DP-b99 (D-Pharm Ltd), HF-0220 (17^-hydroxyepiandrosterone; Newron Pharmaceuticals), HF-0420 (also known as oligotropin), pyridoxal 5'-phosphate (also known as MC-1 ), microplasmin, S-18986, piclozotan, NP031 1 12, tacrolimus, L- seryl-L-methionyl-L-alanyl-L-lysyl-L-glutamyl-glycyl-L-valine, AC-184897 (Acadia

Pharmaceuticals), ADNF-14 (National Institutes of Health), stilbazulenyl nitrone, SUN- N8075 (Daiichi Suntory Biomedical Research), and zonampanel;

(xxvii) nicotinic receptor agonists, such as epibatidine, bupropion, CP-601927, varenicline, ABT-089 (Abbott), ABT-594, AZD-0328 (AstraZeneca), EVP-6124, R3487

(also known as MEM3454; Roche/Memory Pharmaceuticals), R4996 (also known as MEM63908; Roche/Memory Pharmaceuticals), TC-4959 and TC-5619 (both Targacept), and RJR-2403;

(xxviii) norepinephrine (noradrenaline) reuptake inhibitors, such as atomoxetine (STRATTERA), doxepin (APONAL, ADAPIN, SINEQUAN), nortriptyline (AVENTYL,

PAMELOR, NORTRILEN), amoxapine (ASENDIN, DEMOLOX, MOXIDIL), reboxetine (EDRONAX, VESTRA), viloxazine (VIVALAN), maprotiline (DEPRILEPT, LUDIOMIL, PSYMION), bupropion (WELLBUTRIN), and radaxafine; (xxix) phosphodiesterase (PDE) inhibitors, including (a) PDE1 inhibitors (e.g. vinpocetine (CAVINTON, CERACTIN, INTELECTOL) and those disclosed in US Patent No 6,235,742, (b) PDE2 inhibitors (e.g. erythro-9-(2-hydroxy-3-nonyl)adenine (EHNA), BAY 60-7550, and those described in US Patent No. 6, 174,884), (c) PDE3 inhibitors (e.g. anagrelide, cilostazol, milrinone, olprinone, parogrelil, and pimobendan), (d) PDE4 inhibitors (e.g. apremilast, ibudilastroflumilast, rolipram, Ro 20-1724, ibudilast (KETAS), piclamilast (also known as RP73401 ), CDP840, cilomilast (ARIFLO), roflumilast, tofimilast, oglemilast (also known as GRC 3886), tetomilast (also known as OPC-6535), lirimifast, theophylline (UNIPHYL, THEOLAIR), arofylline (also known as LAS-31025), doxofylline, RPR-122818, or mesembrine), and (e) PDE5 inhibitors (e.g. sildenafil (VIAGRA, REVATIO), tadalafil (CIALIS), vardenafil (LEVITRA, VIVANZA), udenafil, avanafil, dipyridamole (PERSANTINE), E-4010, E-4021 , E-8010, zaprinast, iodenafil, mirodenafil, DA-8159, and those disclosed in International Patent Applications

WO2002/020521 , WO2005/049616, WO2006/120552, WO2006/126081 ,

WO2006/126082, WO2006/126083, and WO2007/122466), (f) PDE9 inhibitors (e.g. BAY 73-6691 (Bayer AG) and those disclosed in US Patent Publication Nos

US2003/0195205, US2004/0220186, US2006/01 1 1372, US2006/0106035, and USSN 12/1 18,062 (filed May 9, 2008)), and (g) PDE10 inhibitor such as 2-[4-(1 -Methyl-4- pyridin-4-yl-1 H-pyrazol-3-yl)phenoxymethyl]quinoline, and SCH-1518291 ;

(xxx) quinolines, such as quinine (including its hydrochloride, dihydrochloride, sulfate, bisulfate and gluconate salts), chloroquine, sontoquine, hydroxychloroquine (PLAQUENIL), mefloquine (LARIAM), and amodiaquine (CAMOQUIN, FLAVOQUINE);

(xxxi) β-secretase inhibitors, such as ASP-1702, SCH-745966, JNJ-715754, AMG-0683, AZ-12304146, BMS-782450, GSK-188909, NB-533, LY-2886721 , E-2609, HPP-854, (+)-phenserine tartrate (POSIPHEN), LSN-2434074 (also known as LY- 2434074), KMI-574, SCH-745966, Ac-rER (N²-acetyl-D-arginyl-L-arginine), loxistatin (also known as E64d), and CA074Me;

(xxxii) γ-secretase inhibitors and modulators, such as BMS-708163 (Avagacest), WO20060430064 (Merck), DSP8658 (Dainippon), ITI-009, L-685458 (Merck), ELAN-G, ELAN-Z, 4-chloro-/V-[2-ethyl-1 (S)-(hydroxymethyl)butyl]benzenesulfonamide;

(xxxiii) serotonin (5-hydroxytryptamine) 1A (5-HT_1A) receptor antagonists, such as spiperone, /ei/o-pindolol, BMY 7378, NAD-299, S(-)-UH-301 , NAN 190, lecozotan;

(xxxiv) serotonin (5-hydroxytryptamine) 2C (5-HT2c) receptor agonists, such as vabicaserin, and zicronapine; (xxxv) serotonin (5-hydroxytryptamine) 4 (5-HT₄) receptor agonists, such as PRX-03140 (Epix);

(xxxvi) serotonin (5-hydroxytryptamine) 6 (5-HT₆) receptor antagonists, such as A-964324, AVI-101 , AVN-21 1 , mianserin (TORVOL, BOLVIDON, NORVAL),

methiothepin (also known as metitepine), ritanserin, ALX-1 161 , ALX-1 175, MS-245, LY- 483518 (also known as SGS518; Lilly), MS-245, Ro 04-6790, Ro 43-68544, Ro 63-0563, Ro 65-7199, Ro 65-7674, SB-399885, SB-2141 1 1 , SB-258510, SB-271046, SB-357134, SB-699929, SB-271046, SB-742457 (GlaxoSmithKline), Lu AE58054 (Lundbeck A/S), and PRX-07034 (Epix);

(xxxvii) serotonin (5-HT) reuptake inhibitors such as alaproclate, citalopram

(CELEXA, CIPRAMIL), escitalopram (LEXAPRO, CIPRALEX), clomipramine

(ANAFRANIL), duloxetine (CYMBALTA), femoxetine (MALEXIL), fenfluramine

(PONDIMIN), norfenfluramine, fluoxetine (PROZAC), fluvoxamine (LUVOX), indalpine, milnacipran (IXEL), paroxetine (PAXIL, SEROXAT), sertraline (ZOLOFT, LUSTRAL), trazodone (DESYREL, MOLIPAXIN), venlafaxine (EFFEXOR), zimelidine (NORMUD, ZELMID), bicifadine, desvenlafaxine (PRISTIQ), brasofensine, vilazodone, cariprazine, neuralstem and tesofensine;

(xxxviii) trophic factors, such as nerve growth factor (NGF), basic fibroblast growth factor (bFGF; ERSOFERMIN), neurotrophin-3 (NT-3), cardiotrophin-1 , brain- derived neurotrophic factor (BDNF), neublastin, meteorin, and glial-derived neurotrophic factor (GDNF), and agents that stimulate production of trophic factors, such as propentofylline, idebenone, PYM50028 (COGANE; Phytopharm), and AIT-082

(NEOTROFIN);

(xxxix) Glycine transporter-1 inhibitors such as paliflutine, ORG-25935, JNJ- 17305600, and ORG-26041 ;

(xl) AMPA-type glutamate receptor modulators such as perampanel, mibampator, selurampanel, GSK-729327, and N-((3S, 4S)-4-(4-(5-cyanothiophen-2-yl)phenoxy)

tetrahydrofuran-3-yl)propane-2-sulfonamide; and the like.

The compound of the invention can be given alone or as pharmaceutical compositions comprising a compound of the invention or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable carrier.

As an example, the invention provides a method for treating a condition selected from migraine, anxiety disorders, schizophrenia, and epilepsy. Exemplary anxiety disorders are generalized anxiety disorder, social anxiety disorder, panic disorder, post- traumatic stress disorder and obsessive-compulsive disorder. As another example, the invention provides a method for treating depression selected from Major Depression, Chronic Depression (Dysthymia), Seasonal Depression (Seasonal Affective Disorder), Psychotic Depression, and Postpartum Depression. As another example, the invention provides a method for treating a sleep disorder selected from insomnia and sleep deprivation.

In another embodiment, the invention comprises methods of treating a condition in a mammal, such as a human, by administering an effective amount of a compound of the invention or a pharmaceutically acceptable salt thereof, wherein the condition is selected from the group consisting of atherosclerotic cardiovascular diseases, cerebrovascular diseases and peripheral arterial diseases, to the mammal. The mammal is preferably a mammal in need of such treatment or prevention. Other conditions that may be treated in accordance with the present invention include hypertension and angiogenesis.

In another embodiment, the present invention provides methods of treating neurological and psychiatric disorders associated with glutamate dysfunction, comprising administering to a mammal, preferably a mammal in need thereof, an amount of a compound of the invention or a pharmaceutically acceptable salt thereof effective in treating such disorders.

It will be understood that the intermediate compounds of the invention depicted above are not limited to the particular enantiomer shown, but also include all stereoisomers and mixtures thereof.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 , is the observed X-ray powder diffraction pattern of (5R,7S)-1-(3- fluorophenyl)-8-[4-hydroxy-3-(5-methyl-1 H-pyrazol-1-yl)benzyl]-7-methyl-1 ,8- diazaspiro[4.5]dec-3-en-2-one, hydrochloride monohydrate salt.

Figure 2, is the observed X-ray powder diffraction pattern of (5R,7S)-1-(3- fluorophenyl)-8-[4-hydroxy-3-(5-methyl-1 H-pyrazol-1-yl)benzyl]-7-methyl-1 ,8- diazaspiro[4.5]dec-3-en-2-one, fumarate salt. DETAILED DESCRIPTION

Experiments were generally carried out under inert atmosphere (nitrogen or argon), particularly in cases where oxygen- or moisture-sensitive reagents or intermediates were employed. Commercial solvents and reagents were generally used without further purification, including anhydrous solvents where appropriate. Products were generally dried under vacuum before being carried on to further reactions or submitted for biological testing. Mass spectrometry data is reported from either liquid chromatography-mass spectrometry (LCMS) or gas chromatography-mass spectrometry (GCMS) instrumentation. Chemical shifts for nuclear magnetic resonance (NMR) data are expressed in parts per million (ppm, δ) referenced to residual peaks from the deuterated solvents employed.

Preparation 1

Synthesis of (5 7SV1 -(3-fluorophenyl)-7-methyl-1 ,8-diazaspiror4.51dec-3-en-2- one, hydrochloride salt (P1 )

Step 1. Synthesis of benzyl 2-methyl-4-oxo-3,4-dihvdropyridine-1 (2/-/)- carboxylate (CD. Triethylamine (92.6 g, 0.915 mol) was added to a solution of 4- methoxypyridine (1 .00 kg, 9.16 mol) in tetrahydrofuran (12 L), and the solution was cooled to minus 50 °C. Benzyl chloroformate (1.58 kg, 9.26 mol) was added to the reaction mixture at minus 50 °C. A white precipitate formed; additional tetrahydrofuran (4 L) was added to the reaction mixture to assist in stirring. The reaction mixture was kept at minus 50 °C to minus 10 °C for 1 hour and cooled to minus 78 °C. A solution of methylmagnesium bromide in diethyl ether (3.0 M, 3.67 L, 1 1 mol) was added over 1 hour, while maintaining the reaction temperature at minus 78 °C. The reaction mixture was then allowed to warm to room temperature and stirred for 2 hours. At this point, it was cooled to minus 10 °C and quenched with aqueous hydrochloric acid (2 N, 10 L). Ethyl acetate (15 L) was added, and the layers were separated. The organic layer was washed with aqueous sodium chloride solution (10 L), dried over sodium sulfate, filtered and concentrated to afford the crude product, which was used in the next step without purification. Yield: 1.90 kg, 7.75 mol, 85%. ¹ H NMR (400 MHz, CDCI₃) δ 7.75 (br d, J=7 Hz, 1 H), 7.30-7.45 (m, 5H), 5.34 (br d, J=8 Hz, 1 H), 5.28 (AB quartet, J_AB=12.0 Hz, Δγ_ΑΒ=10.8 Hz, 2H), 4.69-4.70 (br m, 1 H), 2.86 (dd, J=16.5, 6.7 Hz, 1 H), 2.33 (br d, J=16.4 Hz, 1 H), 1.27 (d, J=6.8 Hz, 3H).

Step 2. Synthesis of benzyl 2-methyl-4-oxopiperidine-1 -carboxylate (C2). A solution of benzyl 2-methyl-4-oxo-3,4-dihydropyridine-1 (2H)-carboxylate (C1 ) (1 .40 kg, 5.71 mol) in acetic acid (7 L) was heated to 60 °C. Zinc dust (1.5 kg, 22.9 mol) was added portion-wise over 1 hour, and the reaction was maintained at 60 °C for an additional 2 hours. The reaction mixture was filtered through Celite® using ethyl acetate, and the filtrate was concentrated to an oil. This oil was partitioned between ethyl acetate (10 L) and water (5 L). The organic layer was washed with saturated aqueous sodium bicarbonate solution (3 x 5 L), dried over sodium sulfate, filtered and concentrated. Purification via silica gel chromatography (Eluant: 20% ethyl acetate in petroleum ether) provided the product as a yellow liquid. Yield: 860 g, 3.48 mol, 61 %. ¹H NMR (400 MHz, CDCIs) δ 7.31 -7.43 (m, 5H), 5.18 (s, 2H), 4.75-4.87 (br m, 1 H), 4.28-4.38 (br m, 1 H), 3.40 (ddd, J=13.9, 1 1.2, 3.9 Hz, 1 H), 2.70 (dd, J=14.5, 6.7 Hz, 1 H), 2.51 (ddd, J=15.3, 1 1 .3, 6.9 Hz, 1 H), 2.33-2.41 (m, 1 H), 2.28 (ddd, J=14.6, 2.6, 1.8 Hz, 1 H), 1.22 (d, J=6.8 Hz, 3H).

Step 3. Isolation of benzyl (2S)-2-methyl-4-oxopiperidine-1 -carboxylate (C3). Racemic benzyl 2-methyl-4-oxopiperidine-1-carboxylate (C2) (4.01 kg, 16.2 mol) was dissolved in methanol (80 L) and separated into its enantiomers via chromatography (six Chiralpak AD columns, each 5 cm x 10 cm, 20 μηη, 40 °C; Eluant: methanol; Feed rate 7.2 mL/minute; Eluant rate: 225 mL/minute). The first-eluting enantiomer was the desired (2S) enantiomer, obtained as an amber oil. Yield of benzyl (2S)-2-methyl-4- oxopiperidine-1 -carboxylate (C3): 1 .932 kg, 7.813 mol, 96% with respect to available desired enantiomer. Chiral purity via HPLC analysis: 99.5:0.5 (Column: Chiralpak AD-H, 4.6 mm x 150 mm, 5 μηη; Eluant: 0.1 % trifluoroacetic acid in methanol). {Note: in a similar chiral separation carried out on a different batch of racemic material, conversion to the dimethyl ketal benzyl 4,4-dimethoxy-2-methylpiperidine-1 -carboxylate was observed. This was attributed to slight acidity in the starting material and column packing. A different chiral separation was therefore developed to avoid the presence of alcohol (Column: Chiralpak IA, 20 μηη; Eluant: 60/40 heptane/propan-2-yl acetate). Using six 1 cm x 10 cm columns, a sample of benzyl 2-methyl-4-oxopiperidine-1 -carboxylate (C2) (2.96 g) provided benzyl (2S)-2-methyl-4-oxopiperidine-1-carboxylate (C3) in a 99.5:0.5 ratio with its enantiomer (Chiral purity was assessed via HPLC analysis;

Column: Chiralpak IA, 4.6 mm x 250 mm, 5 μηη; Eluant: 60/40 heptane/propan-2-yl acetate). The desired (2S) enantiomer was the first-eluting enantiomer.}

Step 4. Synthesis of benzyl (2S,4S)-4-hydroxy-2-methyl-4- (trichloromethyl)piperidine-l-carboxylate (C5). Tetrahydrofuran (3.57 L), chloroform (0.86 L, 1 1 mol) and trimethylsilyl chloride (0.94 L, 7.4 mol) were combined in a reactor and the resulting solution was cooled to minus 65 °C. A solution of lithium

bis(trimethylsilyl)amide (1 M in tetrahydrofuran, 6.99 L, 6.99 mol) was added at a slow controlled rate while maintaining the temperature at minus 60 °C to minus 70 °C. The solution was held at minus 65 °C for 30 minutes and was then warmed to minus 20 °C. A solution of benzyl (2S)-2-methyl-4-oxopiperidine-1-carboxylate (C3) (950 g, 3.84 mol) in Λ/JV-dimethylformamide (3.0 L) was slowly added, while maintaining the internal temperature below 5 °C, and then a solution of tetrabutylammonium acetate (0.1 1 kg, 0.36 mol ) in /V,/V-dimethylformamide (0.76 L) was added. The resulting solution was held at minus 5 °C to 5 °C for 12 hours. Water (2.00 L) was charged at a slow controlled rate while maintaining the internal temperature below 30 °C. After addition of tert-butyl methyl ether (2.65 L), the layers were separated, and the organic layer was washed with water (2.70 L), with aqueous hydrochloric acid (1 N, 2.6 L, 2.6 mol) and again with water (2 x 2.65 L). The organic layer was concentrated via vacuum distillation, diluted with 2- methyltetrahydrofuran (1 1 .6 L), and further vacuum distilled to remove tetrahydrofuran. Acetic acid (0.23 L, 4.0 mol) and a solution of tetrabutylammonium fluoride (1 M in tetrahydrofuran, 3.84 L, 3.84 mol) were added to the crude benzyl (2S,4S)-2-methyl-4- (trichloromethyl)-4-[(trimethylsilyl)oxy]piperidine-1-carboxylate in 2-methyltetrahydrofuran (roughly 6 L), and the reaction mixture was held at room temperature for 30 minutes. A solution of potassium carbonate (0.62 kg, 4.5 mol) in water (3.78 L) was added and then the layers were separated. The organic layer was washed three times with water (3 x 3.78 L), then concentrated via vacuum distillation. After addition of dichloromethane (7.56 L), atmospheric distillation was continued until a volume of approximately 4 L was obtained. Additional dichloromethane (7.56 L) was added; the solution was filtered through Florisil® (1 kg) and then concentrated. tert-Butyl methyl ether (5.29 L) was added and atmospheric distillation was continued, to remove dichloromethane. The resulting slurry (approximately 4 L) was cooled to 5 °C and held for 12 hours; the solids were filtered and washed with a mixture of 1 :1 tert-butyl methyl ether/heptane (2 L) to afford the product as a solid. Yield: 0.971 kg, 2.65 mol, 69%. LCMS m/z 368.0 (M+1 ). ¹H NMR (400 MHz, CDCI₃), 1 :1 mixture of rotamers, tabulated as a mixture: δ 7.31 -7.41 (m, 10H), 5.16 (s, 2H) and 5.12-5.22 (m, 2H), 4.65-4.74 (m, 1 H) and 4.56-4.65 (m, 1 H), 4.19-4.27 (m, 1 H) and 4.08-4.16 (m, 1 H), 3.23-3.38 (m, 2H), 2.36 (s, 2H), 2.31 -2.42 (m, 2H), 2.07-2.22 (m, 2H), 1.88-2.05 (m, 4H), 1 .36-1.41 (2 overlapping d, J=7 Hz, 6H).

Step 5. Synthesis of 1 -benzyl 4-methyl (2S,4ffl-4-r(3-ethoxy-3-oxopropanoyl)(3- fluorophenyl)aminol-2-methylpiperidine-1 ,4-dicarboxylate (C7). Methanol (6.48 L) and benzyl (2S,4S)-4-hydroxy-2-methyl-4-(trichloromethyl)piperidine-1 -carboxylate (C5) (1 .30 kg, 3.54 mol) were combined in a reactor and the resulting slurry was cooled to zero °C. 3-Fluoroaniline (1.18 kg, 10.6 mol) was charged and then 1 ,8- diazabicyclo[5.4.0]undec-7-ene (1.97 L, 13.1 mol) was added at a slow controlled rate while maintaining the temperature at minus 5 °C to 5 °C. The solution was warmed to room temperature and then held at 20 °C for 12 hours, at which point the reaction was deemed complete by HPLC analysis. Methanol was removed in vacuo until the reaction volume was approximately 4-5 L; after dilution with tert-butyl methyl ether (10.8 L), the solution was washed three times with 1 M aqueous hydrochloric acid and once with aqueous sodium chloride solution. The terf-butyl methyl ether layer was exchanged with 2-methyltetrahydrofuran and then 2,6-lutidine (826 mL, 7.09 mol) was charged. The resulting solution of crude 1 -benzyl 4-methyl (2S,4f?)-4-[(3-fluorophenyl)amino]-2- methylpiperidine-1 ,4-dicarboxylate was cooled to zero °C and then ethyl 3-chloro-3- oxopropanoate (383 mL, 3.00 mol) was added at a slow controlled rate while maintaining the reaction temperature at minus 5 °C to 5 °C. The reaction mixture was held at zero °C until the reaction was deemed complete by HPLC analysis; this required periodic charging of additional ethyl 3-chloro-3-oxopropanoate (275 g total, 1 .83 mol). 1 M Aqueous hydrochloric acid (6 L) was charged at a slow controlled rate while maintaining the internal temperature below 5 °C. The layers were separated and then the organic layer was washed with 1 M aqueous hydrochloric acid and with aqueous sodium chloride solution. The organic layer was concentrated via vacuum distillation and then 2- methyltetrahydrofuran was added and vacuum distillation was continued to remove residual water. The concentrated solution was diluted with 2-methyltetrahydrofuran to an approximate volume of 1 1 L; this solution was used directly in the following reaction.

Step 6. Synthesis of benzyl (5R7SV1 -(3-fluorophenylV7-methyl-2.4-dioxo-1.8- diazaspiror4.51decane-8-carboxylate (C9). The solution of 1 -benzyl 4-methyl (2S,4f?)-4- [(3-ethoxy-3-oxopropanoyl)(3-fluorophenyl)amino]-2-methylpiperidine-1 ,4-dicarboxylate (C7) in 2-methyltetrahydrofuran from the previous step was divided into two equal portions, and each was carried on as follows. The solution was charged into a reactor and diluted with additional 2-methyltetrahydrofuran (5.5 L); a solution of sodium ethoxide in ethanol (20%, 0.76 L, 2.0 mol) was added at a slow controlled rate while maintaining the temperature at 15 °C to 25 °C. The solution was held at 20 °C for 4 hours. A solution of citric acid (0.42 kg, 2.0 mol) in water (2.5 L) was added, followed by addition of 1 M aqueous hydrogen chloride (2.0 L, 2.0 mol) and then the aqueous layer was removed. Water (3.5 L) was added to the solution of crude 8-benzyl 3-ethyl (5f?,7S)-1-(3- fluorophenyl)-7-methyl-2,4-dioxo-1 ,8-diazaspiro[4.5]decane-3,8-dicarboxylate and the reaction mixture was slowly heated (over 1 hour) to reflux and maintained at that temperature until the reaction was judged to be complete by HPLC analysis. The reaction mixture was cooled to room temperature and the phases were separated. The organic layer was washed with water (5.9 L) and with aqueous sodium chloride solution and was then concentrated via vacuum distillation. 2-methyltetrahydrofuran (5.9 L) was added and vacuum distillation was continued to remove residual water. The resulting solution (3.25 kg) was divided into two equal portions for purification of the product, and each was processed as follows. The solution was concentrated to a residue of approximately 900 g, dissolved in 1 :1 ethyl acetate/heptane (2 L), and pumped through a column of silica gel (330 g) using 1 :1 ethyl acetate/heptane (6 L) as eluant. Mixed fractions were evaporated under reduced pressure to yield a dark residue (777 g), which was dissolved in 2-methyltetrahydrofuran (3.1 L) and treated with heptane in 500 ml_ portions. After addition of 2 L of heptane and seeding, the solution became cloudy; after an additional hour of stirring, copious solid was present. Additional heptane (1 L) was added, and the mixture was stirred for 18 hours at room temperature. Clean product fractions from the column were evaporated to roughly 100 g of residue, which was dissolved in 2-methyltetrahydrofuran (200 mL), and treated slowly with 50 mL portions of heptane. After addition of 135 mL of heptane, the solution became cloudy; stirring for an additional hour produced massive crystallization. terf-Butyl methyl ether (200 mL) was added, and the slurry was held without agitation for 18 hours. The two crystallizations were filtered together, and the resulting solid was washed with 1 :1 heptane/tert-butyl methyl ether to provide the product (236 g). The other half of the reaction product was similarly treated to provide 257.6 g of material. Repetitive processing of the filtrates provided additional product. Combined yield: 573.2 g, 1.397 mol. Total yield over steps 5 and 6: 39%. LCMS m/z 41 1 .1 (M+1 ). ¹ H N MR (400 MHz, CDCI₃) δ 7.44 (ddd, J=8.2, 8.1 , 6.2 Hz, 1 H), 7.27-7.37 (m, 5H), 7.17 (br ddd, J=8, 8, 2 Hz, 1 H), 6.93 (ddd, J=7.9, 1 .8, 0.8 Hz, 1 H), 6.88 (ddd, J=9.0, 2.3, 2.2 Hz, 1 H), 4.99-5.10 (m, 2H), 4.33-4.46 (br s, 1 H), 4.07 (br d, J=13 Hz, 1 H), 3.53 (br dd, J=13, 13 Hz, 1 H), 3.31 (AB quartet, J_AB=21 .9 Hz, Δγ_ΑΒ=61.5 Hz, 2H), 1.95-2.06 (m, 2H), 1 .85 (ddd, J=14.2, 2.6, 1.7 Hz, 1 H), 1.67-1 .79 (br m, 1 H), 1.26 (d, J=7.1 Hz, 3H).

Step 7. Synthesis of (5R7S)-1 -(3-fluorophenyl)-7-methyl-1 ,8-diazaspiror4.5ldec- 3-en-2-one, hydrochloride salt (PP. 2-Methyltetrahydrofuran (4.04) and ethanol (4.04 L) were charged into a reactor, followed by benzyl (5f?,7S)-1-(3-fluorophenyl)-7-methyl-2,4- dioxo-1 ,8-diazaspiro[4.5]decane-8-carboxylate (C9) (0.50 kg, 1.23 mol). Sodium borohydride (40 g, 1.1 mol) was added at a slow controlled rate while maintaining the temperature at 15 °C to 25 °C. The solution was held at 20 °C ± 5 °C until the reaction was deemed complete by HPLC analysis. Acetone (0.50 L) was added and the reaction mixture was held for 30 minutes and then concentrated via vacuum distillation to a final volume of approximately 3 L. Toluene (5.05 L) was added and the mixture was washed with aqueous hydrochloric acid (1 M, 2 x 2 L) and with aqueous sodium chloride solution. The organic layer was concentrated via vacuum distillation to a final volume of approximately 3 L. Toluene (5.05 L) was added and vacuum distillation was continued to remove residual water and provide a concentrated solution of benzyl (5f?,7S)-1 -(3- fluorophenyl)-4-hydroxy-7-methyl-2-oxo-1 ,8-diazaspiro[4.5]decane-8-carboxylate. After addition of dichloromethane (10.0 L, plus 5.0 L to rinse reactor and filter), the mixture was filtered through Florisil (0.50 kg) and then concentrated to an approximate volume of 10.0 L. Triethylamine (0.31 L, 2.2 mol) was charged into the reactor and the solution was cooled to 10 °C ± 3 °C. Methanesulfonyl chloride (0.17 L, 2.2 mol) was added at a slow controlled rate while maintaining the temperature at 10 °C ± 3 °C, and the reaction mixture was then held at 10 °C ± 3 °C for 20 minutes, at which time the reaction was deemed complete by HPLC analysis. 1 ,8-Diazabicyclo[5.4.0]undec-7-ene (0.67 L, 4.4 mol) was charged and the reaction mixture was held at 10 °C ± 3 °C for 20 minutes, at which time the reaction was deemed complete by HPLC analysis. The reaction mixture was washed with aqueous hydrochloric acid (1 M, 2 x 4 L) and with aqueous sodium chloride solution. The organic layer was subjected to vacuum distillation to provide a concentrated solution of benzyl (5f?,7S)-1 -(3-fluorophenyl)-7-methyl-2-oxo-1 ,8- diazaspiro[4.5]dec-3-ene-8-carboxylate. Solvent was displaced with methanol, and the mixture was finally concentrated to a volume of approximately 2 L. Water (1 .4 L) and concentrated aqueous hydrochloric acid (37%, 1.4 L) was charged and the reaction mixture was heated to reflux until the reaction was deemed complete by HPLC analysis. Dichloromethane (2.5 L) was charged and layers were separated; this was repeated for a total of three washes. The product-rich aqueous layer was basified with aqueous sodium hydroxide (50%, 1.9 kg, 24 mol), and the product was extracted into

dichloromethane (3 x 2.5 L). The product-rich organic layer was concentrated via vacuum distillation and then ethyl acetate was added and vacuum distillation was continued to remove dichloromethane, to a final volume of approximately 4 L. In a separate reactor, a solution of hydrogen chloride in ethyl acetate was prepared by adding acetyl chloride (0.14 L, 2.0 mol) to a mixture of ethyl acetate (1.0 L) and methanol (0.10 L, 2.5 mol). This hydrogen chloride solution in ethyl acetate was added at a slow controlled rate to the product solution in ethyl acetate; the reaction mixture was held at room temperature for 2 hours and then heated to 50 °C for 1 hour. The product slurry was cooled to room temperature and filtered. The wet cake was washed with ethyl acetate (2.0 L) and dried in a tray dryer under vacuum, to afford (5f?,7S)-1 -(3- fluorophenyl)-7-methyl-1 ,8-diazaspiro[4.5]dec-3-en-2-one, hydrochloride salt (P1 ) as a solid. Yield: 0.245 kg, 0.826 mol, 67%. LCMS m/z 261 .2 (M+1 ). ¹H NMR (400 MHz, DMSO-cf₆ δ 8.65-9.03 (2 overlapping br s, 2H), 7.49-7.58 (m, 2H), 7.31 -7.37 (m, 2H), 7.20 (ddd, J=7.8, 1.8, 0.9 Hz, 1 H), 6.28 (d, J=6.0 Hz, 1 H), 3.22-3.31 (br m, 1 H), 3.02- 3.13 (br m, 1 H), 2.60-2.70 (br m, 1 H), 2.07-2.21 (m, 3H), 1 .91 -2.00 (m, 1 H), 1 .24 (d, J=6.6 Hz, 3H).

Preparation 2 Synthesis of 4-hydroxy-3-(5-methyl-1 H-pyrazol-l -vDbenzaldehvde (P2)

C13

C12

Step 1. Synthesis of 1 -(5-bromo-2-methoxyphenyl)-5-methyl-1 H-pyrazole (C14). Boron trifluoride-tetrahydrofuran complex (777 g, 5.55 mol) was slowly added to a solution of 5-bromo-2-methoxyaniline (799.8 g, 3.96 mol) in 2-methyltetrahydrofuran (5.3 L), and the mixture was filtered through Celite®. The filtrate was brought to a volume of 9 L with additional 2-methyltetrahydrofuran. In a separate container, tert-butyl nitrite (433 g, 4.20 mol) was dissolved in 2-methyltetrahydrofuran (8.0 L); the volume was then adjusted to 9 L by addition of 2-methyltetrahydrofuran. The two solutions were pumped by two Ismatec syringe pumps, both of which had been calibrated to deliver 15 mL/minute of 2-methyltetrahydrofuran, into a T-mixer connected to a 240 ml_ polytetrafluoroethylene (PTFE) coil for diazonium salt formation. At a combined flow rate of 30 mL/minute, the reaction mixture had a total residence time of 8 minutes in the coil to facilitate complete diazonium salt formation. The syringe pumps were started simultaneously, and the material was passed through the coil into a two-stage continuous flow stirred-tank reactor, where the 5-bromo-2-methoxybenzenediazonium tetrafluoroborate product (C12) was continuously extracted into water, using a water pump with a flow rate of 20 to 22.5 mL/minute. The aqueous layer was continuously separated in a stand pipe decanter, and then quenched into a jacketed 20 L reactor containing a mixture of tin(ll) chloride dihydrate (2.28 kg, 12.0 mol), 2- methyltetrahydrofuran (4 L) and water (4 L) at zero °C. When the reduction had provided complete conversion to (5-bromo-2-methoxyphenyl)hydrazine (C13), as monitored by HPLC analysis, a solution of (3E)-4-(dimethylamino)but-3-en-2-one (454 g, 4.01 mol) in 2-methyltetrahydrofuran (3.0 L) was charged, and the jacket temperature was adjusted to 20 °C. After 14 hours, analysis of the organic layer indicated that hydrazine C13 had been consumed. The layers were separated, and the organic layer was washed with aqueous sodium hydroxide solution (6 N, 2 x 5 L). Silica gel (1 .0 kg) was added to the organic phase, and the mixture was concentrated to dryness and dried at 35 °C and 100 mbar vacuum on a rotary evaporator until a free-flowing powder was obtained. This powder was loaded onto a pad of silica gel (100 g), and elution was carried out with 2- methyltetrahydrofuran (6 L); the eluant was concentrated in vacuo to provide the product as a thick dark red oil. ¹H NMR data indicated that this material was comprised of a roughly 9:1 ratio of the title product and the regioisomeric pyrazole. Yield: 573 g, 2.15 mol, 67% (corrected for 80% purity of starting 5-bromo-2-methoxyaniline). GCMS m/z 266, 268 (M⁺). ¹H NMR (400 MHz, CDCI₃) title product peaks only: δ 7.60 (d, J=1 .8 Hz, 1 H), 7.52 (dd, half of ABX pattern, J=8.7, 2.4 Hz, 1 H), 7.49 (d, half of AB pattern, J=2.4 Hz, 1 H), 6.92 (d, J=8.7 Hz, 1 H), 6.16-6.18 (m, 1 H), 3.79 (s, 3H), 2.16 (br s, 3H).

Step 2. Synthesis of 4-bromo-2-(5-methyl-1 /-/-pyrazol-1 -yl)phenol (C15).

Dichlorophenylborane (0.51 kg, 3.2 mol) was added at a slow controlled rate to a solution of 1 -(5-bromo-2-methoxyphenyl)-5-methyl-1 H-pyrazole (C14) (0.57 kg, 2.13 mol) in toluene (5.73 L), while maintaining the temperature at 20 °C ± 10 °C. The reaction mixture was heated to 95 °C ± 5 °C and held at this temperature for 3 hours, at which time the reaction was deemed complete by HPLC analysis. Aqueous sodium hydroxide solution (1 N, 9.4 L, 9.4 mol) was added at a slow controlled rate while maintaining the temperature at 20 °C ± 10 °C, and the reaction mixture was stirred for 30 minutes. The organic layer was extracted with 1 N aqueous sodium hydroxide (2.6 L, 2.6 mol). Concentrated aqueous hydrogen chloride (37%) was added to the combined aqueous layers at a slow controlled rate, while maintaining the temperature at 20 °C ± 5 °C, until a pH of 9-10 was achieved. The resulting solid was collected by filtration, washed with water (2.86 L) and dried under a stream of nitrogen. The wet cake was mixed with isopropyl alcohol (4.58 L) and the slurry was heated to 50 °C ± 5 °C for 1 hour, at which point all solids had dissolved. The solution was cooled to 20 °C ± 5 °C and then water (4.58 L) was added slowly over 1 hour. This slurry was held at 20 °C ± 5 °C for 2 hours, then filtered, washed with water (2.86 L) and dried in a tray dryer under vacuum to afford the title product. The minor pyrazole regioisomer was no longer present, by ¹ H NMR analysis. Yield: 352 g, 1 .39 mol, 65% LCMS m/z 253.0, 255.0

(M+1 ). ¹H NMR (400 MHz, DMSO-cf₆) δ 10.40 (s, 1 H), 7.50 (apparent br dd, J=1.8, 0.5 H; likely a broadened dq, J=1 .8, 0.5 Hz; 1 H), 7.47 (dd, J=8.8, 2.5 Hz, 1 H), 7.37 (d, J=2.5 Hz, 1 H), 7.00 (d, J=8.8 Hz, 1 H), 6.17-6.19 (m, 1 H), 2.12-2.13 (m, 3H).

Step 3. Synthesis of 4-hydroxy-3-(5-methyl-1 /- -pyrazol-1 -yl)benzaldehyde (P2). 4-Bromo-2-(5-methyl-1 H-pyrazol-1 -yl)phenol (C15) (1 17.7 g, 464.9 mmol) was dissolved in tetrahydrofuran (1.18 L) and cooled in a dry ice/acetone bath. The resulting slurry was treated drop-wise with methyllithium (3.0 M in 1 ,2-dimethoxyethane, 232.5 ml_, 697.4 mmol) over 35 minutes, while maintaining the reaction temperature below minus 55 °C. After 1 .75 hours, sec-butyllithium (1 .4 M in cyclohexane, 498.2 ml_, 697.4 mmol) was added drop-wise over an hour, while the reaction temperature was maintained below minus 55 °C. The reaction was stirred for 15 minutes, and then morpholine-4- carbaldehyde (66.1 ml_, 658 mmol), in an equal volume of tetrahydrofuran, was added drop-wise over 20 minutes, while the reaction temperature was held below minus 55 °C. After 5 minutes, the reaction was allowed to slowly warm to minus 8 °C, at which time chilled aqueous hydrochloric acid (2 N, 465.0 ml_, 929.9 mmol) was rapidly added; the temperature was maintained below 30 °C during this addition. The organic phase was extracted with water (3 L), and the combined aqueous layers were treated drop-wise with aqueous hydrochloric acid (6 N, 77.49 ml_, 465.0 mmol) over 6 minutes. To the resulting slurry was added additional aqueous hydrochloric acid (6 N, 52.7 ml_, 316.2 mmol) over 7 minutes, and the resulting mixture was allowed to granulate under nitrogen for 18 hours. Filtration provided a solid, which was washed with water (940 ml.) and dried at 40 °C under vacuum to provide the title product as a light orange granular solid. Yield: 80.96 g, 400.4 mmol, 86%. LCMS m/z 203.1 (M+1 ). ¹H NMR (400 MHz, CDCI₃) δ 9.90 (s, 1 H), 7.86 (d, J=1 .8 Hz, 1 H), 7.76 (dd, J=8.4, 2.0 Hz, 1 H), 7.68 (br d, J=2.0 Hz, 1 H), 7.24 (d, J=8.3 Hz, 1 H), 6.31 -6.33 (m, 1 H), 2.54 (s, 3H). Example 1

Synthesis of (5R7S)-1 -(3-fluorophenyl)-8-r4-hvdroxy-3-(5-methyl-1 /-/-pyrazol-1 - yl)benzyll-7-methyl-1 ,8-diazaspiror4.5ldec-3-en-2-one, hydrochloride salt (1 )

(5f?,7S)-1-(3-Fluorophenyl)-7-methyl-1 ,8-diazaspiro[4.5]dec-3-en-2-one, hydrochloride salt (P1 ) (91.70 g, 309.0 mmol) and 4-hydroxy-3-(5-methyl-1 H-pyrazol-1- yl)benzaldehyde (P2) (69.40 g, 343.2 mmol) were combined in tetrahydrofuran (1.76 L). Triethylamine (57.60 ml_, 413.3 mmol) was added to the slurry, and the mixture was stirred for 30 minutes. Sodium triacetoxyborohydride (91 .2 g, 430 mmol) was added in one portion, and the reaction mixture was allowed to stir for 18 hours. At this point, aqueous hydrochloric acid (1 M, 800 ml_, 800 mmol) was added, providing a solution of pH approximately 4. The pH was adjusted to approximately 8 using aqueous sodium hydroxide solution (1 M, then a 50% solution). The aqueous layer was extracted with ethyl acetate (2 x 800 ml_), and the combined organic layers were washed with water (2 x 800 ml_), then with saturated aqueous sodium chloride solution (300 ml_). Removal of solvent in vacuo provided a light yellow residue, which was purified via silica gel chromatography (Eluant: ethyl acetate) to afford the neutral form of the title product as a slightly yellow hard foam. Yield: 108 g, 242 mmol, 78%. ¹H NMR (400 MHz, CDCI₃) δ 9.42 (s, 1 H), 7.65 (d, J=1 .6 Hz, 1 H), 7.39-7.45 (m, 2H), 7.1 1-7.17 (m, 2H), 7.08 (dd, half of ABX pattern, J=8.4, 2.0 Hz, 1 H), 7.01 (d, half of AB pattern, J=8.4 Hz, 1 H), 6.94 (ddd, J=7.8, 1.8, 1.0 Hz, 1 H), 6.88 (ddd, J=9.4, 2, 2 Hz, 1 H), 6.25-6.27 (m, 1 H), 6.24 (d, J=6.0 Hz, 1 H), 3.51 (AB quartet, J_AB=13.5 Hz, Δγ_ΑΒ=61 .2 Hz, 2H), 2.98-3.07 (m, 1 H), 2.66 (ddd, J=12.5, 10.0, 3.0 Hz, 1 H), 2.43 (ddd, J=12.5, 5.3, 4.4 Hz, 1 H), 2.35 (s, 3H), 2.1 1 (dd, J=13.3, 5.1 Hz, 1 H), 1.97 (ddd, J=13.0, 10.0, 4.2 Hz, 1 H), 1.68-1 .76 (m, 1 H), 1 .55- 1.63 (m, 1 H), 1.16 (d, J=6.6 Hz, 3H).

(5R,7S)-1-(3-Fluorophenyl)-8-[4-hydroxy-3-(5-methyl-1 H-pyrazol-1-yl)benzyl]-7- methyl-1 ,8-diazaspiro[4.5]dec-3-en-2-one (1 14.7 g, 256.9 mmol) was dissolved in dichloromethane (100 mL) and diethyl ether (4 L). A solution of hydrogen chloride in diethyl ether (2 M, 122 mL, 244 mmol) was added over less than 5 minutes, and the resulting mixture was stirred for one hour. The solid was filtered and washed with diethyl ether (1 .0 L), then dried using a nitrogen press to provide the title product as an off-white amorphous solid. Yield: 108 g, 224 mmol, 92%. LCMS m/z 447.2 (M+1 ). ¹H NMR (400 MHz, DMSO-c e), roughly 60:40 mixture of rotamers: δ 1 1.09-1 1.19 and 9.92-10.05 (2 br s, total 1 H), 10.52 and 10.53 (appears as 2 overlapping singlets, total 1 H), 7.88 (d, J=6.2 Hz, 0.6H), [7.01 -7.16, 7.19-7.26, 7.28-7.38 and 7.44-7.57 (4 m, total 8H)], 6.99 (d, J=8.4 Hz, 0.4H), 6.36 (d, J=6.2 Hz, 0.6H), 6.17-6.23 (overlapping d, J=5.9 Hz, at 6.22 and ddd, J=10.2, 1 .7, 0.8 Hz, at 6.19; total 1.4H), 4.10-4.25 (m, 2H), [2.72-2.83 (br m), 3.09-3.19 (br d, J=12 Hz), 3.25-3.33 (br d, J=12 Hz), 3.37-3.52 (br m, presumed; obscured by water peak) and 3.67-3.77 (br s), total 3H], 2.13 (s, 1 .2H), 2.12 (s, 1 .8H), [1.82-1.97 (br m) and 2.12-2.48 (m), total 4H], 1.43-1 .50 (2 overlapping d, J= 6 Hz, 3H).

A sample of the neutral form of the title compound (32 mg, 0.072 mmol) was dissolved in tetrahydrofuran (0.30 mL) and mixed with a solution of concentrated aqueous hydrochloric acid (12 M, 5.7 μΙ_, 0.069 mmol) in methanol (10 μΙ_). After vigorous shaking, the mixture was allowed to sit uncovered for 2 hours, and covered for 18 hours. The resulting solid was isolated by filtration, then slurried in ethyl acetate; after sitting uncovered for 66 hours, crystals of (5f?,7S)-1-(3-fluorophenyl)-8-[4-hydroxy-3-(5- methyl-1 H-pyrazol-1-yl)benzyl]-7-methyl-1 ,8-diazaspiro[4.5]dec-3-en-2-one,

hydrochloride salt had formed that were appropriate for Single Crystal X-ray Diffraction analysis. The absolute configuration of the title product was established via X-ray crystallography.

Single Crystal X-ray Structure Determination

(5R,7S)-1-(3-Fluorophenyl)-8-[4-hydroxy-3-(5-methyl-1 H-pyrazol-1-yl)benzyl]-7- methyl-1 ,8-diazaspiro[4.5]dec-3-en-2-one, hydrochloride salt (1 ) was subjected to single crystal X-ray structure determination to elucidate its absolute stereochemistry. Crystallographic data is provided below in Table I.

Experimental Details

Data collection was performed on a Bruker AXS SMART-APEX II diffractometer at room temperature with graphite-monochromated MoK_a-radiation. The diffractometer is equipped with a CCD area detector and controlled using APEX II software (see Apex 2 v 2008 4.0 control software, Bruker AXS Inc., Madison, Wl 2007). A small crystal, 0.23 x 0.20 x 0.08 mm in size, was used in the data collection. Intensities were integrated (see Bruker SAINT v7.56A integration software, Bruker AXS Inc., Madison, Wl 2007) from three series of exposures, in which each exposure covered 0.3° in ω over 30 seconds. A full-sphere of data was collected and the raw data was subsequently corrected for absorption using the multiscans method (see SADABS, Program for scaling and correction of area detector data, G. M. Sheldrick, University of Gottingen, Germany, 1997, based on the method of R. H. Blessing, Acta Cryst. 1995, A51, 33-38).

Structure Solution and Refinement

The structure was solved by direct methods using SHELXS97 (see SHELXS-97, Program for crystal structure solution, G. M. Sheldrick, University of Gottingen,

Germany, 1997, release 97-2) in the monoclinic space group P2. The structure was subsequently refined by full-matrix least-squares method using SHELXL97 (see

SHELXL-97, Program for crystal structure refinement, G. M. Sheldrick, University of Gottingen, Germany, 1997, release 97-2) based on 1 1716 unique reflections. It was found that the asymmetric unit contained two ion pairs of (5f?,7S)-1 -(3-fluorophenyl)-8- [4-hydroxy-3-(5-methyl-1 /-/-pyrazol-1-yl)benzyl]-7-methyl-1 ,8-diazaspiro[4.5]dec-3-en-2- one, hydrochloride salt (1 ). At this stage it was found that there was some small amount of residual electron density in the structure. This was refined as two water molecules with full occupancy. This structure therefore represents the monohydrate of (5f?,7S)-1- (3-fluorophenyl)-8-[4-hydroxy-3-(5-methyl-1 H-pyrazol-1 -yl)benzyl]-7-methyl-1 ,8- diazaspiro[4.5]dec-3-en-2-one, hydrochloride salt (1 ). All non-hydrogen atoms were found and refined using anisotropic displacement parameters.

The hydrogen atoms on nitrogen and oxygen were initially found from a Fourier difference map. The O-H bond lengths in the water molecules were restrained to 0.9 A, while the other O/N-H bonds were subsequently refined freely. All remaining hydrogen atoms on carbon were fixed geometrically. The final refinement included isotropic displacement parameters for all H atoms.

Assignment of Stereochemistry

From the crystal structure it was possible to assign the absolute configuration directly from the X-ray diffraction data, provided that the assumption was made that the crystal was enantiopure (see H. D. Flack, Acta Cryst. 1983, A39, 876-881 ). The structure was refined as the enantiomer depicted above [(5f?,7S)] with a Flack X parameter of -0.0208(0.0454). The stereochemistry of both molecules was the same. Pertinent crystal, data collection and structure refinement details are summarized Table 1.

Table 1 . Crystal data and structure refinement

Data / restraints / 1 1716 / 5 / 657

parameters

2

Goodness-of-fit on F 0.998

Final R indices [l>2sigma(l)] R¹ = 0.0480, wR² = 0.0902

R indices (all data) R¹ = 0.0926, wR² = 0.1064

Absolute structure -0.02(5)

parameter

Largest diff. peak and hole 0.198 and -0.203 e.A^"3

The physical properties of the monohydrate of (5f?,7S)-1 -(3-fluorophenyl)-8-[4- hydroxy-3-(5-methyl-1 H-pyrazol-1 -yl)benzyl]-7-methyl-1 ,8-diazaspiro[4.5]dec-3-en-2- one, hydrochloride salt (1 ) were evaluated using Powder X-Ray Diffraction (PXRD) (Figure 1 ).

The calculated powder pattern was generated from the single crystal data using Mercury version 2.3 software (Cambridge Crystallographic Data Centre). A copper wavelength of 1.5406 A (Cu K_a), a step size of 0.02 and a full width at half max peak shape of 0.1 was used to generate the x-ray pattern. Generally, preliminary peak assignments on the PXRD pattern calculated from the crystal structure were conducted using a Threshold value of 0.25 and a Width value of 0.3. The output of automated assignments was visually checked to ensure validity and adjustments manually made if necessary. Additionally, peaks were manually assigned within spectra if appropriate (see Table 2).

Table 2. Peak list for monohydrate form of (5f?,7S)-1 -(3-Fluorophenyl)-8-[4- hvdroxy-3-(5-methyl-1 /-/-pyrazol-1-yl)benzyll-7-methyl-1 ,8-diazaspiro[4.5ldec-3-en-2- one, hydrochloride salt^*

10.2 17

1 1.8 48

12.1 66

12.5 16

12.8 24

13.3 34

13.7 30

14.4 54

15.1 53

15.5 74

15.5 67

16.3 16

16.6 31

17.1 31

17.7 74

18.0 56

18.7 59

19.1 25

19.8 59

20.2 58

20.5 43

20.7 49

21.3 100

22.9 62

23.7 62

23.9 62

24.3 77

24.9 42

25.4 31

25.7 27

26.2 29

26.6 30

26.8 24 27.7 13

28.1 17

28.5 25

28.8 39

29.1 33

29.3 34

29.9 42

30.0 40

30.1 36

30.5 28

30.9 29

31.3 23

31.5 25

32.0 19

32.3 19

32.7 27

33.4 27

33.5 22

33.7 19

34.6 22

34.9 27

35.8 16

36.0 16

36.8 25

37.2 26

37.4 20

37.6 27

37.8 26

38.4 15

39.0 20

39.3 15

39.5 13

39.9 15

^*Standard Deviation of 2-Theta ° is ± 0.2 Example 2

Synthesis of (5R,7S)-1 -(3-fluorophenyl)-8-r4-hvdroxy-3-(5-methyl-1 H-pyrazol-1 - yl)benzyll-7-methyl-1 ,8-diazaspiror4.51dec-3-en-2-one, fumarate salt

A sample of the neutral form of the title compound (91 mg, 0.204 mmol) was dissolved in tetrahydrofuran (0.5 ml.) and mixed with a solution of fumaric acid (23.7 mg, 0.204 mmol) in methanol (50 μΙ_). After vigorous shaking, the mixture was allowed to sit uncovered for 2 hours, and then covered for 18 hours. The resulting solid was isolated by filtration, then slurried in ethyl acetate; after sitting uncovered for 24 hours, crystals of (5R,7S)-1-(3-fluorophenyl)-8-[4-hydroxy-3-(5-methyl-1 H-pyrazol-1-yl)benzyl]-7-methyl- 1 ,8-diazaspiro[4.5]dec-3-en-2-one, fumarate salt (2) had formed. ¹H NMR (400 MHz, METHANOL-d₄) δ 7.61 (d, J = 6.06 Hz, 1 H), 7.53 (d, J = 1 .76 Hz, 1 H), 7.46 (d, J = 6.46 Hz, 1 H), 7.13 - 7.28 (m, 3H), 6.99 - 7.07 (m, 2H), 6.95 (d, J = 8.41 Hz, 1 H), 6.67 (s, 2H), 6.24 (d, J = 6.06 Hz, 1 H), 6.20 (dd, J = 0.78, 1.96 Hz, 1 H), 3.89 - 4.00 (m, 1 H), 3.80 - 3.90 (m, 1 H), 3.17 - 3.26 (m, 1 H), 3.07 - 3.16 (m, 1 H), 2.67 - 2.79 (m, 1 H), 2.21 - 2.31 (m, 1 H), 2.16 (s, 3H), 2.08 - 2.14 (m, 1 H), 1.88 - 1.97 (m, 1 H), 1.38 (dd, J = 1 .57, 6.65 Hz, 3H). Anal calcd for C₂₆H27FN₄0₂.C₄H₄0₄: C, 64.05; H, 5.55; N, 9.96. Found: C, 63.89; H, 5.27; N, 9.82.

The physical properties of (5f?,7S)-1 -(3-Fluorophenyl)-8-[4-hydroxy-3-(5-methyl- 1 H-pyrazol-1-yl)benzyl]-7-methyl-1 ,8-diazaspiro[4.5]dec-3-en-2-one, fumarate salt (2) were evaluated using Powder X-Ray Diffraction (PXRD) (Figure 2).

The Powder Diffraction analysis was conducted using a Bruker D8 diffractometer equipped with a Cu radiation source, fixed slits (divergence^ .0 mm, anti-scatter=0.6 mm, and receiving=0.6 mm) and a scintillation counter detector. Data was collected in the Theta-Theta goniometer at the Cu wavelength Και =1.54056 A from 3.0 to 40.0 degrees 2-Theta using a step size of 0.040 degrees and a step time of 2.0 second. X- ray tube voltage and amperage were set at 40 kV and 40 mA respectively. Samples were prepared by placement in a Nickel Disk (Gasser & Sons, Inc. Commack, NY). Data were collected and analyzed using Bruker DIFFRAC Plus software (Version 2.6). PXRD data files (.raw) were not processed prior to peak searching. Generally, a Threshold value of 1 and a Width value of 0.3 were used to make preliminary peak assignments. The output of automated assignments was visually checked to ensure validity and adjustments manually made if necessary. Additionally, peaks were manually assigned within spectra if appropriate (see Table 3).

Table 3. Peak list for (5R7SV1 -(3-Fluorophenyl>8-r4-hvdroxy-3-(5-methyl-1 H-

PVrazol-1-yl)benzyll-7-methyl-1 ,8-diazaspiro[4.5ldec-3-en-2-one, fumarate salt^*

24.6 40

25.5 24

27.0 18

27.7 21

28.5 46

29.4 22

30.6 17

34.1 20

35.8 17

36.2 14

38.4 15

^*Standard Deviation of 2-Theta ° is ± 0.2

The compound described herein may be formulated in any form suitable for the desired route of delivery using a pharmaceutically effective amount of the compound. For example, the compositions disclosed herein may be delivered by a route such as oral, dermal, transdermal, intrabronchial, intranasal, intravenous, intramuscular, subcutaneous, parenteral, intraperitoneal, intranasal, vaginal, rectal, or by sustained release.

A pharmaceutically effective amount of the compound(s) may vary depending on the specific compound(s), mode of delivery, severity of the condition being treated, and any other active ingredients used in the formulation or the selected regimen. The dosing regimen may be adjusted to provide the optimal therapeutic response. Several divided doses may be delivered daily or a single daily dose may be delivered.

However, the dosage to be used in the treatment or prevention of a specific cognitive deficit or other condition may be subjectively determined by the attending physician. The variables involved include the specific cognitive deficit and the size, age and response pattern of the patient. For example, based upon the activity profile and potency of the compound of the invention, a starting dose of about 25 mg per day with gradual increase in the daily dose to about 525 mg per day may provide the desired dosage level in the human. The dose may however, be proportionally reduced or increased as indicated by the exigencies of the therapeutic situation.

The compound may be administered to a subject by any desirable route, taking into consideration the specific condition for which it has been selected. By subject is meant any suitable mammal, including humans, domestic animals (e.g., canines and felines), and livestock, which have been recognized as having or at risk of having one or more of the conditions for which modulation of beta amyloid levels is desirable. Thus, the compound of the invention is useful for treatment and/or prevention of a number of human and veterinary conditions. As used herein, "prevention" encompasses prevention of symptoms in a subject who has been identified as at risk for the condition, but has not yet been diagnosed with same and/or who has not yet presented any symptoms thereof.

The compound of the invention may be delivered or administered by any suitable route of delivery, e.g., orally, intravenous, subcutaneous, intramuscular, sublingual, intracranial, epidural, intratracheal, rectal, vaginal, among others. The compound may be delivered orally or by a suitable parenteral. The compound may be formulated in combination with conventional pharmaceutical carriers that are physiologically compatible. Optionally, the compound of the invention may be mixed with other active agents.

Suitable physiologically compatible carriers may be readily selected by one of skill in the art. For example, suitable solid carriers include, among others, one or more substances which may also act as lubricants, solubilizers, suspending agents, fillers, glidants, compression aids, binders or tablet-disintegrating agents or an encapsulating material. In powders, the carrier is a finely divided solid, which is in admixture with the finely divided active ingredient. In tablets, the active ingredient is mixed with a carrier having the necessary compression properties in suitable proportions and compacted in the shape and size desired. The powders and tablets may contain up to 99% of the active ingredient. Suitable solid carriers include, for example, starch, sugars (including, e.g., lactose and sucrose), calcium phosphate, cellulose (including, e.g., microcrystalline cellulose, methyl cellulose, sodium carboxymethyl cellulose), kaolin, magnesium stearate, talc, dextrin, gelatin, polyvinylpyrrolidine, low melting waxes, and ion exchange resins.

Liquid carriers may be used in preparing solutions, suspensions, emulsions, syrups and elixirs. The active ingredient may be dissolved or suspended in a

pharmaceutically acceptable liquid carrier such as water, an organic solvent, a mixture of both or pharmaceutically acceptable oils or fat. The liquid carrier may contain other suitable pharmaceutical additives such as solubilizers, emulsifiers, buffers,

preservatives, sweeteners, flavoring agents, suspending agents, thickening agents, colors, viscosity regulators, stabilizers or osmo-regulators. Suitable examples of liquid carriers for oral and parenteral administration include water (particularly containing additives as above e.g. cellulose derivatives, such as, sodium carboxymethyl cellulose solution), alcohols (including monohydric alcohols and polyhydric alcohols e.g. glycols) and their derivatives, and oils (e.g. fractionated coconut oil and arachis oil). For parenteral administration the carrier may also be an oily ester such as ethyl oleate and isopropyl myristate. Sterile liquid carriers are used in sterile liquid form compositions for parenteral administration.

Optionally, additives customarily employed in the preparation of pharmaceutical compositions, such as, for example, sweeteners or other flavoring agents, coloring agents, preservatives, and antioxidants, e.g., vitamin E, ascorbic acid, BHT and BHA.

Liquid pharmaceutical compositions, which are sterile solutions or suspensions, may be utilized by, for example, intramuscular, intraperitoneal or subcutaneous injection. Sterile solutions may also be administered intravenously. Oral administration may be either liquid or solid composition form.

The pharmaceutical composition may be in unit dosage form, e.g. as tablets or capsules. In such form, the composition is sub-divided in unit dose containing appropriate quantities of the active ingredient; the unit dosage forms may be packaged compositions, for example, packeted powders, vials, ampoules, prefilled syringes or sachets containing liquids. The unit dosage form may be, for example, a capsule or tablet itself, or it may be the appropriate number of any such compositions in package form.

Alternatively, the use of sustained delivery devices may be desirable, in order to avoid the necessity for the patient to take medications on a daily basis. "Sustained delivery" is defined as delaying the release of an active agent, i.e., a claimed compound, until after placement in a delivery environment, followed by a sustained release of the agent at a later time. Those of skill in the art know suitable sustained delivery devices. Examples of suitable sustained delivery devices include, e.g., hydrogels (see, e.g., US Patent Nos. 5,266,325; 4,959,217; 5,292,515), an osmotic pump, such as described by Alza (US Patent No. 4,295,987 and US Patent No. 5,273,752) or Merck (European Patent No. 314,206), among others; hydrophobic membrane materials, such as ethylenemethacrylate (EMA) and ethylenevinylacetate (EVA); bioresorbable polymer systems (see, e.g., International Patent Publication No. WO 98/44964, Bioxide and Cellomeda; US Patent No. 5,756, 127 and US Patent No. 5,854,388); other

bioresorbable implant devices have been described as being composed of, for example, polyesters, polyanhydrides, or lactic acid/glycolic acid copolymers (see, e.g., US Patent No. 5,817,343 (Alkermes Inc.)). For use in such sustained delivery devices, the compound of the invention may be formulated as described herein.

As has been mentioned previously, elevated beta amyloid levels in brain correlate with cognitive decline. The claimed compound has utility for the prevention and treatment of AD by virtue of their ability to reduce beta amyloid production. Cellular, cell- free and in vivo screening methods to detect inhibitors of beta amyloid production are known in the art (for example International Patent Publication No. WO 98/22493, European Patent No. 0 652 009, US Patent No. 5,703,129 and US Patent No.

5,593,846). Additionally, the claimed compound has utility for the prevention and/or treatment of disorders involving beta amyloid production including cerebrovascular diseases. The compound of the invention has also been shown to inhibit beta amyloid production employing the cellular assays described below.

The compound of the invention is an inhibitor of beta amyloid production. In preliminary studies using protease specific assays, the compound of the invention has been shown to exhibit specific inhibition with respect to protease activity. Thus, the claimed compounds are useful for treatment and prevention of a variety of conditions in which modulation of beta amyloid levels provides a therapeutic benefit. Such conditions include, for example, amyloid angiopathy, cerebral amyloid angiopathy, systemic amyloidosis, Alzheimer's Disease (AD), hereditary cerebral hemorrhage with

amyloidosis of the Dutch type, inclusion body myositis, Down's syndrome, among others.

In addition, the compound of the invention may be utilized in generating reagents useful in diagnosis of conditions associated with abnormal levels of beta amyloid. For example, the compound of the invention may be used to generate antibodies which would be useful in a variety of diagnostic assays. Methods for generating monoclonal, polyclonal, recombinant, and synthetic antibodies or fragments thereof are well known to those of skill in the art. See, e.g., E. Mark and Padlin, "Humanization of Monoclonal Antibodies", Chapter 4, The Handbook of Experimental Pharmacology, Vol. 1 13, The Pharmacology of Monoclonal Antibodies, Springer-Verlag (June, 1994); Kohler and

Milstein and the many known modifications thereof; International Patent Application No. PCT/GB85/00392; British Patent Application Publication No. GB2188638A; Amit et al., Science, 233:747-753 (1986); Queen et al., Proc. Natl Acad. Sci. USA, 86:10029-10033 (1989); International Patent Publication No. WO90/07861 ; and Riechmann et al., Nature, 332:323-327 (1988); Huse et al, Science, 246:1275-1281 (1988). Alternatively, the compound of the invention may themselves be used in such diagnostic assays.

Regardless of the reagent selected (e.g., antibody or compound of Formula (I)), suitable diagnostic formats including, e.g., radioimmunoassays and enzyme-linked

immunosorbent assays (ELISAs), are well known to those of skill in the art.

Biological Assays and Data

Fluorescent Polarization (FP) Assay

Beta-Secretase (BACE) is one of the enzymes involved in the generation of the Amyloid Beta peptide found in the Amyloid plaques of Alzheimer's patients. This assay measures the inhibition of the beta-Secretase enzyme as it cleaves a non-native peptide substrate.

The fluorescent tagged synthetic substrate, Biotin-GLTNIKTEEISEISY^AEVEFR- C[oregon green]KK-OH can be efficiently cleaved by the beta-Secretase enzyme and is therefore useful to assay beta-secretase activity in the presence or absence of inhibitory compounds. The histidine tagged BACE1 enzyme was affinity purified material from conditioned media of CHO-K1 cells that had been transfected to express soluble, truncated BACE enzyme (BACE1 deltaTM96His). Compounds were incubated in a ½ log dose response (from a top concentration of 100uM) with BACE1 enzyme (0.1 nM final) and the biotinylated fluorescent peptide substrate (150nM final) in assay buffer containing 100mM Sodium Acetate, pH4.5 (brought to pH with Acetic Acid), and 0.001 % Tween-20. Total reaction volumes of 30 μΙ_ were carried out in 384-well black plates (Thermo Scientific #4318). Plates were covered and incubated for 3hr at 37°C. The reactions were then stopped by addition of 30ul of 1 .5uM Streptavidin (Pierce, #21 125). After 10 minutes incubation at room temperature, plates were read on a PerkinElmer Envision for fluorescence polarization (Ex485 nm/ Em530 nm). The activity of the beta- secretase enzyme is detected by changes in the fluorescence polarization (Δ mP) that occur when the substrate is cleaved by the enzyme. Incubation in the presence of compound inhibitor demonstrates specific inhibition of beta-Secretase enzymatic cleavage of the peptide substrate. Results for the compound of the invention are provided in Table 1 .

ELISA Assay The following assay measures BACE inhibition as a decrease in soluble Amyloid Precursor Protein (sAPP). H4 cells were stably transfected with wild type APP which is the substrate for BACE. Cleavage of APP by BACE results in the secretion of sAPP into the media. Inhibition of BACE enzyme prevents the formation and secretion of sAPP.

The neuroglioma cell line H4 cells are grown in Dulbecco's Modified Eagle

Medium (DMEM) with 10% FBS, 200mM L-Glutamine, and 50mg/ml Geneticin. Cells are plated over night in tissue culture treated 384 well plates from Falcon at a cell density of 4,500 cells/well in 50uL of media. The next day media is removed, cells are washed once with phosphate buffered saline after which 25uL media is placed in all wells. 2.5uL of a 10x compound dose response curve is added to the cells. The final compound top dose is at 30uM with 1 % DMSO and compounds are diluted by half log 1 1 times. Compounds are allowed to incubate with cells overnight in a 37°C incubator. Concurrently, 384 well clear Nunc Maxisorp plates are incubated overnight at 4°C with 10ul of 4ug/ml antibody from clone mAbP2-1 which was generated to recognize the soluble form of APP and available from Pierce (OMA1 -03132).

The next day the coated plates are blocked with 1 % BSA in PBS/TWEEN 20 (0.05%) for an hour and then washed 3 times with PBS/Tween. Firstly, 10uL of media from the treated cells is transferred to the washed plates and incubated at ambient temperature for an hour and then washed again. Secondly, a 10ul aliquot of a 1 :1000 dilution of antibody 192 from Elan Pharmaceuticals which recognizes the BACE cleavage site of sAPP is added and incubated for an hour. Thirdly, the plates are washed and then incubated with 10ul of a 1 :1000 dilution of anti-rabbit, HRP tagged antibody from Pierce. Plates are washed one last time and developed with 10ul SureBlue TMB from Kirkegaard & Perry Laboratories (KPL). Once the plate has developed to a blue color, 10uL of 0.09M Sulfuric Acid is added to stop the color reaction. Plates are then read at an absorbance of 450 nm on an Envision plate reader. Results for the compound of the invention are provided ion Table 1 .

Table 1

Comparison Studies

An analysis was done comparing IC₅₀ and HLM Intrinsic Clearance of the claimed compound, (5R,7S)-1-(3-fluorophenyl)-8-(4-hydroxy-3-(5-methyl-1 H-pyrazol-1 - yl)benzyl)-7-methyl-1 ,8-diazaspiro[4.5]dec-3-en-2-one, with (5R,7S)-8-(3-(1 H-pyrazol-1- yl)benzyl)-1 -(3-fluorophenyl)-7-methyl-1 ,8-diazaspiro[4.5]dec-3-en-2-one, a compound, Example 64, from International Patent Publication W010/058333 published May 27, 2010. Results can be seen in Table 2 below.

TABLE 2

HLM Intrinsic Clearance

Metabolic Incubations. Human liver microsomal incubations were conducted in triplicate. General conditions are described as follows with details specific to each drug listed in Table 1. Incubation mixtures consisted of liver microsomes (0.3-10 mg microsomal protein/ml), substrates (1 .0 μΜ), MgCI₂ (3.3 mM), and NADPH (1.3 mM) in a total volume of 0.5 ml potassium phosphate buffer (25 mM, pH 7.5). Reactions were commenced with the addition of NADPH and shaken in a water bath open to the air at 37°C. At T 5 0 and at five time points ranging to 40 min, aliquots (50 ml) were removed and added to termination mixtures containing internal standards as listed in Table 1. The samples were processed by extraction into methyl t-butyl ether (3 ml), the aqueous layer was frozen in a dry ice-acetone bath, and the organic solvent was decanted and evaporated under N2 at 30°C. The residue was reconstituted in 50 ml HPLC mobile phase A (see below). For methoxsalen samples, the work-up procedure consisted of precipitation of protein with acetonitrile (100 ml), removal of precipitated materials by centrifugation, and analysis of the supernatant by HPLC-mass spectrometry (MS).

The preceding analyses indicates (5R,7S)-1-(3-fluorophenyl)-8-(4-hydroxy-3-(5- methyl-1 H-pyrazol-1-yl)benzyl)-7-methyl-1 ,8-diazaspiro[4.5]dec-3-en-2-one has improved IC₅₀ and Intrinsic Clearance when compared against a literature compound, Example 64, from International Patent Publication W010/058333 published May 27, 2010.

Cellular, cell-free and in vivo screening methods to detect inhibitors of beta amyloid production are known in the art. Such assays may include radioimmunoassays and enzyme-linked immunosorbent assay (ELISA), among others. See, e.g., P.D.

Mehta, et al., Techniques in Diagnostic Pathology, vol. 2, eds., Bullock et al, Academic Press, Boston, pages 99-1 12 (1991 ), International Patent Publication No. WO 98/22493, European Patent No. 0 652 009, US Patent No. 5,703,129 and US Patent No.

5,593,846. Additionally, the use of in vitro drug metabolism data in the understanding of in vivo pharmacokinetic data has recently become an area of scientific interest in the prediction of human clearance (see e.g., R. Scott Obach, Prediction of Human

Clearance of Twenty-Nine Drugs from Hepatic Microsomal Intrinsic Clearance Data: An Examination of In Vitro Half-Life Approach and Nonspecific Binding to Microsomes, Drug Metabolism and Disposition, Vol. 27, No. 1 1 , May 17, 201 1 ; and Thomas A. Lanz, et al., Pharmacodynamics and Pharmacokinetics of the γ-Secretase Inhibitor, The Journal of Pharmacology and Experimental Therapeutics, Vol. 334, No. 1 , May 1 1 , 201 1 ). Any references cited herein are incorporated by reference it their entirety.

Claims

We Claim:

1. A compound having the structure of Formula I:

or a pharmaceutically acceptable salt thereof.

A compound having the structure of Formula I

wherein the stereochemistry shown in Formula la is the absolute stereochemistry,

or a pharmaceutically acceptable salt thereof.

3. A compound of Claim 2, wherein said compound is the hydrochloride salt.

4. A compound of Claim 2, wherein said compound is the hydrochloride

monohydrate salt.

5. A compound of Claim 4, wherein said compound is the crystalline polymorph of a hydrochloride monohydrate salt of the compound of Formula la with X-ray diffraction 2- Theta reflections wherein at least one of the reflections is about 8.3, 12.1 or 14.4.

6. A compound of Claims 4-5, wherein said compound is the crystalline polymorph of a hydrochloride monohydrate salt of the compound of Formula la with X-ray diffraction 2-Theta reflections wherein at least two of the reflections are about 8.3, 12.1 or 14.4.

7. A compound of Claims 4-6, wherein said compound is the crystalline polymorph of a hydrochloride monohydrate salt of the compound of Formula la with X-ray diffraction

2-Theta reflections are about 8.3, 12.1 or 14.4.

8. A compound of Claim 2, wherein said compound is the fumarate salt.

9. A compound of Claim 2, wherein said compound is the anhydrous fumarate salt.

10. A compound of Claim 9, wherein said compound is the crystalline polymorph of anhydrous fumarate salt.

1 1 . A compound of Claim 10, wherein said compound is the crystalline polymorph of anhydrous fumarate salt with X-ray diffraction 2-Theta reflections wherein at least one of the reflections is about 9.7, 10.9 or 15.9.

12. A compound of Claims 10-1 1 , wherein said compound is the crystalline polymorph of anhydrous fumarate salt with additional X-ray diffraction 2-Theta reflections wherein at least two of the reflections are about 9.7, 10.9 or 15.9.

13. A compound of Claim 10-12, wherein said compound is the crystalline polymorph of anhydrous fumarate salt with additional X-ray diffraction 2-Theta reflections wherein the reflection are about 9.7, 10.9 or 15.9.

14. A method for the treatment of a disease or condition selected from the group consisting of neurological and psychiatric disorders comprising administering to the mammal an effective amount of compound of claims 1 or 2, or pharmaceutically acceptable salt thereof.

15 A method according to Claim 14, wherein the neurological disorder is selected from the group consisting of migraine; epilepsy; Alzheimer's disease; Parkinson's disease; brain injury; stroke; cerebrovascular diseases, cerebral arteriosclerosis, cerebral amyloid angiopathy, hereditary cerebral hemorrhage, brain hypoxia-ischemia, cognitive disorders, amnesia, senile dementia, HIV associated dementia, Alzheimer's disease, Huntington's disease, Lewy body dementia, vascular dementia, drug related dementia, tardive dyskinesia, myoclonus, dystonia, delirium, Pick's disease, Creutzfeldt- Jacob disease, HIV disease, Gilles de la Tourette's syndrome, epilepsy, muscular spasms and disorders associated with muscular spasticity or weakness, tremors, mild cognitive impairment); mental deficiency, spasticity, Down syndrome, fragile X syndrome, sleep disorders, hypersomnia, circadian rhythm sleep disorder, insomnia, parasomnia and sleep deprivation.

16. A method according to Claim 15, wherein the psychiatric disorder is selected from the group consisting of anxiety, acute stress disorder, generalized anxiety disorder, social anxiety disorder, panic disorder, post-traumatic stress disorder, agoraphobia, obsessive-compulsive disorder, factitious disorder, acute hallucinatory mania, impulse control disorders, compulsive gambling, intermittent explosive disorder, mood disorders, bipolar I disorder, bipolar II disorder, mania, mixed affective state, major depression, chronic depression, seasonal depression, psychotic depression, seasonal depression, premenstrual syndrome (PMS) premenstrual dysphoric disorder (PDD), postpartum depression, psychomotor disorder, psychotic disorders, schizophrenia, schizoaffective disorder, schizophreniform, delusional disorder, drug dependence, narcotic dependence, alcoholism, amphetamine dependence, cocaine addiction, nicotine dependence, drug withdrawal syndrome, eating disorders, anorexia, bulimia, binge eating disorder, hyperphagia, obesity, compulsive eating disorders, pagophagia, sexual dysfunction disorders, urinary incontinence, neuronal damage disorders, ocular damage, retinopathy or macular degeneration of the eye, tinnitus, hearing impairment and loss, brain edema, pediatric psychiatric disorders, attention deficit disorder, attention deficit/hyperactive disorder, conduct disorder and autism.

17. A pharmaceutical composition comprising a compound of claims 1 or 2, or a pharmaceutically acceptable salt thereof and a pharmaceutically acceptable carrier.

18. The composition of Claim 17, further comprising an atypical antipsychotic, a cholinesterase inhibitor, or a NMDA receptor antagonist.