Substituted tetrahydroisoquinoline derivatives as d1 positive allosteric modulators

Abstract

The present application relates to compounds according to formula (I) which are positive allosteric modulators of D1 and accordingly beneficially used as a medicament for the treatment of diseases in which D1 receptors play a role.

Description

[0001] This invention relates to tetrahydroisoquinoline derivatives and their therapeutic applications. In particular, this invention relates to pharmacologically active substituted tetrahydroisoquinoline derivatives.

[0002] This compound functions as a D1 positive allosteric regulator and is therefore beneficially used as a pharmaceutical agent for treating diseases in which the D1 receptor plays a role.

[0003] Monoamine dopamine regulates motor function, reward mechanisms, cognitive processes, and other physiological functions through two families of GPCRs. Specifically, dopamine acts on neurons via D1 class (including dopamine D1 and D5) and D2 class (including D2, D3, and D4) receptors. D1 class receptors primarily interact with GPCRs. s G-proteins couple to and thereby stimulate cAMP production, while D2 receptors couple to Gi / qG proteins and reduce cAMP production. These receptors are widely expressed in different brain regions. In particular, D1 receptors are involved in many physiological functions and behavioral processes. For example, D1 receptors are involved in synaptic plasticity, cognitive function and goal-oriented motor function, as well as reward processes. Due to their roles in several physiological / neurological processes, D1 receptors have been involved in a variety of disorders, including cognitive and negative symptoms in schizophrenia, cognitive impairment involving neuroleptic treatment, mild cognitive impairment (MCI), impulsive behavior, attention deficit hyperactivity disorder (ADHD), Parkinson's disease and other motor disorders, dystonia, Parkinson's dementia, Huntington's disease, Lewy body dementia, Alzheimer's disease, substance addiction, sleep disorders, apathy, traumatic spinal cord injury, or neuropathic pain.

[0004] It has been established that developing orally bioavailable small molecules targeting the D1 receptor is challenging. Currently developed D1 agonists are generally characterized by a catechol moiety, thus limiting their clinical application to invasive treatments. Achieving sufficient selectivity has also been a challenge due to the high homology of ligand binding sites between dopamine receptor subtypes (e.g., dopamine D1 and D5). Furthermore, D1 agonists are associated with potential limiting side effects, including but not limited to movement disorders and hypotension.

[0005] Therefore, it is necessary to design new reagents that can regulate the D1 receptor.

[0006] Identifying allosteric modulators of GPCRs has been of great interest, serving as tools for understanding receptor mechanisms and as potential therapeutic agents. GPCRs represent the largest family of cell surface receptors, and many commercially available drugs directly activate or block signal transduction pathways mediated by these receptors. However, for some GPCRs (e.g., peptide receptors), it has proven challenging to develop small molecules or achieve sufficient selectivity due to the high homology of ligand binding sites between subtypes (e.g., dopamine D1 and D5 or D2 and D3). Accordingly, much drug research has shifted to identifying small molecules that target sites different from those of ortho-natural agonists. Ligands binding to these sites induce conformational changes in GPCRs, thereby allosterically modulating receptor function. Allosteric ligands possess a diverse range of activities, including the ability to enhance (positive allosteric modulators, PAM) or attenuate (negative allosteric modulators, NAM) the effects of endogenous ligands by influencing affinity and / or potency. From a drug discovery perspective, in addition to subtype selectivity, allosteric modulators may have other potential advantages, such as lack of direct effects or intrinsic potency; enhancing the effects of natural delivery agents only at the point and time of their release; reducing the tendency to induce desensitization due to constant exposure to agonists; and reducing the tendency to induce target-related side effects.

[0007] The compounds according to the invention enhance the effect of D1 agonists or endogenous ligands on D1 receptors through an allosteric mechanism and are therefore positive allosteric modulators of D1 (D1 PAM).

[0008] Therefore, the compounds according to the invention, as D1 PAMs, are beneficial for the treatment and / or prevention of diseases and disorders in which D1 receptors function. These diseases include cognitive and negative symptoms in schizophrenia, cognitive impairment requiring neuroleptic treatment, mild cognitive impairment (MCI), impulsive behavior, attention deficit hyperactivity disorder (ADHD), Parkinson's disease and other movement disorders, dystonia, Parkinson's dementia, Huntington's disease, Lewy body dementia, Alzheimer's disease, substance addiction, sleep disorders, apathy, traumatic spinal cord injury, or neuropathic pain.

[0009] International patent application WO 2014 / 193781 A1 discloses certain 3,4-dihydroisoquinoline-2(1H)-yl derivatives for the treatment of cognitive impairment associated with Parkinson's disease or schizophrenia.

[0010] International patent application WO 2017 / 178377 discloses certain substituted 3,4-dihydroisoquinoline-2(1H)-yl derivatives and their analogues as D1 positive allosteric modifiers.

[0011] International patent application n°PCT / EP2020 / 068183 (publication number WO2021 / 001288) discloses 2-(3,5-dichloro-1-methyl-indazol-4-yl)-1-[(1S,3R)-3-(hydroxymethyl)-5-(1-hydroxy-1-methyl-ethyl)-1-methyl-3,4-dihydro-1H-isoquinoline-2-yl] ethyl ketone.

[0012] However, there is still a need to develop alternative and effective D1 positive allosteric modifiers.

[0013] This invention provides 2-(3,5-dichloro-indazol-4-yl)-1-[(1S,3R)-3-(hydroxymethyl)-5-(1-hydroxy-1-methyl-ethyl)-1-methyl-3,4-dihydro-1H-isoquinoline-2-yl] ethyl ketone of formula (I).

[0014]

[0015] Or its pharmaceutically acceptable salt.

[0016] The present invention also provides compounds of formula (I) as defined above, or pharmaceutically acceptable salts thereof, for use in treatment.

[0017] Although some D1 PAM compounds, as mentioned above, have been disclosed in the prior art, the precise structures of the compounds described herein have not been disclosed in advance.

[0018] In another aspect, the present invention also provides compounds of formula (I) as defined above, or pharmaceutically acceptable salts thereof, for the treatment of diseases and / or disorders in which the D1 receptor functions.

[0019] In another aspect, the present invention provides compounds of formula (I) as defined above, or pharmaceutically acceptable salts thereof, for the treatment and / or prevention of cognitive and negative symptoms in schizophrenia, including cognitive impairment related to neuroleptic treatment, mild cognitive impairment (MCI), impulsive behavior, attention deficit hyperactivity disorder (ADHD), Parkinson's disease and other movement disorders, dystonia, Parkinson's dementia, Huntington's disease, Lewy body dementia, Alzheimer's disease, drug addiction, sleep disorders, apathy, traumatic spinal cord injury, or neuropathic pain.

[0020] In specific embodiments of this aspect, the present invention provides a compound of formula (I) as defined above, or a pharmaceutically acceptable salt thereof, for the treatment of cognitive and negative symptoms in Parkinson's disease and other movement disorders, Alzheimer's disease, or schizophrenia.

[0021] Therefore, in one particular aspect, the present invention provides compounds of formula (I) as defined above, or pharmaceutically acceptable salts thereof, for the treatment of Parkinson's disease and other movement disorders.

[0022] In another aspect, the present invention provides the use of a compound of formula (I) as defined above or a pharmaceutically acceptable salt thereof for the preparation of a medicament for the treatment and / or prevention of diseases and / or disorders in which the D1 receptor functions.

[0023] In another additional aspect, the present invention provides the use of a compound of formula (I) as defined above, or a pharmaceutically acceptable salt thereof, for the preparation of a medicament for the treatment and / or prevention of cognitive and negative symptoms in schizophrenia, cognitive impairment related to neuroleptic treatment, mild cognitive impairment (MCI), impulsive behavior, attention deficit hyperactivity disorder (ADHD), Parkinson's disease and other movement disorders, dystonia, Parkinson's dementia, Huntington's disease, Lewy body dementia, Alzheimer's disease, drug addiction, sleep disorders, apathy, traumatic spinal cord injury, or neuropathic pain.

[0024] In specific embodiments of this aspect, the present invention provides the use of a compound of formula (I) as defined above or a pharmaceutically acceptable salt thereof for the preparation of a medicament for the treatment of cognitive and negative symptoms in Parkinson's disease and other movement disorders, Alzheimer's disease or schizophrenia.

[0025] In one particular aspect, the present invention provides the use of a compound of formula (I) as defined above, or a pharmaceutically acceptable salt thereof, for the preparation of a medicament for the treatment of Parkinson's disease and other movement disorders.

[0026] The present invention also provides a method for treating and / or preventing obstacles to the administration of a D1 positive allosteric modulator, comprising administering to a patient requiring treatment an effective amount of a compound of formula (I) as defined above or a pharmaceutically acceptable salt thereof.

[0027] In another aspect, the present invention provides a method for treating and / or preventing cognitive and negative symptoms in schizophrenia, cognitive impairment involving neuroleptic treatment, mild cognitive impairment (MCI), impulsive behavior, attention deficit hyperactivity disorder (ADHD), Parkinson's disease and other movement disorders, dystonia, Parkinson's dementia, Huntington's disease, Lewy body dementia, Alzheimer's disease, drug addiction, sleep disorders, apathy, traumatic spinal cord injury, or neuropathic pain, comprising administering to a patient in need of treatment an effective amount of a compound of formula (I) as defined above or a pharmaceutically acceptable salt thereof.

[0028] In a specific embodiment of this invention, the present invention provides a method for treating cognitive and negative symptoms in Parkinson's disease and other movement disorders, Alzheimer's disease or schizophrenia, comprising administering to a patient in need of treatment an effective amount of a compound of formula (I) as defined above or a pharmaceutically acceptable salt thereof.

[0029] In one particular aspect, the present invention provides a method for treating Parkinson's disease and other movement disorders, comprising administering to a patient in need of treatment an effective amount of a compound of formula (I) as defined above or a pharmaceutically acceptable salt thereof.

[0030] For use in pharmaceuticals, salts of compounds of formula (I) shall be pharmaceutically acceptable salts. However, other salts may be used to prepare compounds of formula (I) or their pharmaceutically acceptable salts. The basic standard principles for selecting and preparing pharmaceutically acceptable salts are described, for example, in Handbook of Pharmaceutical Salts: Properties, Selection and Use, ed. P.Stahl & C.G. Wermuth, Wiley-VCH, 2002. Suitable pharmaceutically acceptable salts of compounds of formula (I) include acid addition salts, which may be formed, for example, by mixing a solution of a compound of formula (I) with a solution of a pharmaceutically acceptable acid.

[0031] It should be understood that each individual atom present in formula (I) or in the formula described below can, in fact, exist in any of its naturally occurring isotopes, with the most abundant isotope being preferred. Thus, by way of example, each individual hydrogen atom present in formula (I) or in the formula described below can be as… 1 H, 2 H (deuterium) or 3 The presence of H (tritium) atoms is preferred. 1 H. Similarly, as an example, each individual carbon atom present in equation (I) or in the equation described below can be considered as 12 C 13 C or 14 The presence of C atoms is preferred. 12 C.

[0032] This invention includes solvates of compounds of formula (I) above within its scope. The solvates can be formed using common organic solvents or water.

[0033] This invention also includes, within its scope, cocrystals of compounds of formula (I) above. The technical term "cocrystal" is used to describe a situation in which neutral molecular components are present in a crystalline compound in a defined stoichiometric ratio. The preparation of pharmaceutical cocrystals allows for alteration of the crystal form of the active pharmaceutical ingredient, which in turn alters its physicochemical properties without impairing its desired biological activity (see Pharmaceutical Salts and Cocrystals, eds. J. Wouters and L. Quere, RSC Publishing, 2012).

[0034] The compounds according to the invention can exist in different polymorphic forms. Although not explicitly stated in the above formula, such forms are intended to be included within the scope of the invention.

[0035] In a particular aspect of the invention, the compound of formula (I) is isolated as a monohydrate as further described in the examples.

[0036] The scope of this invention also includes the prodrug forms of compounds of formula (I) and their various subscopes and subclasses.

[0037] Activity in any of the aforementioned therapeutic indications or disorders can, of course, be determined by conducting appropriate clinical trials in a manner known to a person skilled in the art in relation to that particular indication and / or in general clinical trial design.

[0038] For the purpose of treating disease, compounds of formula (I) or pharmaceutically acceptable salts thereof may be used at an effective daily dose and administered in the form of a pharmaceutical composition.

[0039] Therefore, the present invention also provides pharmaceutical compositions comprising a compound of formula (I) above or a pharmaceutically acceptable salt thereof, and one or more pharmaceutically acceptable carriers in combination therewith.

[0040] In order to prepare the pharmaceutical composition according to the invention, one or more compounds of formula (I) or pharmaceutically acceptable salts thereof are closely mixed with a pharmaceutical diluent or carrier according to conventional pharmaceutical mixing techniques known to those skilled in the art.

[0041] Suitable diluents and carriers can be in a variety of forms, depending on the desired route of administration, such as oral, rectal, parenteral, or intranasal.

[0042] The pharmaceutical compositions according to the invention can be administered, for example, orally, parenterally (i.e., intravenously, intramuscularly, or subcutaneously), intrathecally, by inhalation, or intranasally.

[0043] Pharmaceutical compositions suitable for oral administration can be solid or liquid and can be in the form of, for example, tablets, pills, lozenges, gelatin capsules, solutions, syrups, chewing gum, etc.

[0044] For this purpose, the active ingredient can be mixed with an inert diluent or a non-toxic, pharmaceutically acceptable carrier such as starch or lactose. Optionally, these pharmaceutical compositions may also contain binders such as microcrystalline cellulose, tragacanth gum or gelatin, disintegrants such as alginate, lubricants such as magnesium stearate, glidants such as colloidal silica, sweeteners such as sucrose or saccharin, or colorants or flavorings such as peppermint or methyl salicylate.

[0045] The present invention also contemplates compositions capable of releasing active substances in a controlled manner. Pharmaceutical compositions suitable for parenteral administration are in conventional forms such as aqueous or oily solutions or suspensions, typically contained in ampoules, disposable syringes, glass or plastic vials, or infusion containers.

[0046] In addition to the active ingredients, these solutions or suspensions may optionally contain sterile diluents such as water for injection, physiological saline solutions, oils, polyethylene glycol, glycerin, propylene glycol or other synthetic solvents, antimicrobial agents such as benzyl alcohol, antioxidants such as ascorbic acid or sodium bisulfite, chelating agents such as ethylenediaminetetraacetic acid, buffers such as acetates, citrates or phosphates, and molar osmolarity regulators such as sodium chloride or dextrose.

[0047] These drug forms are prepared using methods routinely employed by pharmacists.

[0048] The amount of compounds used in this invention required to prevent or treat a specific condition will vary depending on the compound chosen and the condition of the patient to be treated. However, the daily dose can typically range from 0.05 to 3000 mg, and for parenteral compositions, it is generally from 0.5 mg to 1000 mg.

[0049] The compounds of the invention or pharmaceutically acceptable salts thereof may be administered alone (monotherapy) or in combination with L-DOPA (combination therapy). The compounds of formula (I) of the invention or pharmaceutically acceptable salts thereof may be used to treat movement disorders associated with L-DOPA administration, alone or in combination with L-DOPA dose fractions required to improve a patient's motor impairment. For example, if the compounds of formula (I) of the invention are used together with or alone as a substitute for L-DOPA in a patient's L-DOPA dose fraction, it is believed that the compounds of formula (I) of the invention will effectively combat motor impairment without inducing troublesome movement disorders. Therefore, the compounds of the invention are believed to be used to treat motor deficits and levodopa-induced movement disorders (LID).

[0050] Therefore, in a particular aspect, the present invention also provides a compound of formula (I) for treating levodopa-induced dyskinesia (LID).

[0051] Compound (I) can be prepared by a two-step method involving the reaction of intermediate (II) with intermediate (III), wherein P1 and P2 are protecting groups such as tert-butyldimethylsilyl and trimethylsilyl, respectively, followed by a deprotection step.

[0052]

[0053] In a suitable solvent containing an excess base, such as N,N-diisopropylethylamine, such as dimethylformamide, intermediate (III) can be readily reacted with intermediate (II) in the presence of (1-cyano-2-ethoxy-2-oxoethoxyaminooxy)dimethylamino-morpholino-carbocationic hexafluorophosphate (COMU) or another coupling agent known to those skilled in the art. The resulting intermediate can be directly deprotected in THF using a fluoride-based reagent such as tetrabutylammonium fluoride (TBAF) or according to any method known to those skilled in the art.

[0054] Intermediate (III) can be prepared by a reaction involving intermediate (IV).

[0055]

[0056] in

[0057] Z represents halogen or 1-hydroxy-1-methylethyl;

[0058] R a Represents tert-butyldimethylsilyl; and

[0059] R c It represents hydrogen or tert-butyloxycarbonyl.

[0060] In the first step, Z represents bromine and R c The intermediate of formula (IV) representing hydrogen (hereinafter referred to as intermediate (IVa)) can be protected with a suitable protecting group according to methods known to those skilled in the art, wherein Z represents bromine and R c Compound of formula (IV) representing tert-butyloxycarbonyl (hereinafter referred to as intermediate (IVb)).

[0061] In the second step, the metal-halogen exchange reaction can be carried out according to the method described in the appended examples, for example in the presence of n-BuLi, in a suitable solvent such as tetrahydrofuran, at low temperature, and in the presence of anhydrous acetone in a continuous flow, to provide the corresponding intermediate (IV) described above, wherein Z represents 1-hydroxy-1-methylethyl, hereinafter referred to as intermediate (IVc).

[0062] Then, according to methods known to those skilled in the art or as further described in the appended examples, the protected tert-butyloxycarbonyl (Boc) group (R) is first deprotected. c ), providing intermediate (III).

[0063] The intermediate of formula (IVa) can be prepared by a reaction involving the intermediate of formula (V), where Y is a halogen such as bromine, and R... a The intermediate of formula (IV) is defined as above.

[0064]

[0065] The reaction is conveniently carried out in the presence of methylmagnesium chloride, in a suitable solvent such as tetrahydrofuran, and at low temperature.

[0066] Intermediate (V) can be prepared by a two-step method involving the reaction of intermediate (VI).

[0067]

[0068] Where Y is defined as the intermediate of equation (V) above and R a It represents hydrogen or tert-butyl-dimethylsilyl.

[0069] In the first step, R is placed in the presence of a suitable base, such as 4-dimethylamino-pyridine, at room temperature. a The intermediate (VI), representing hydrogen, reacts with tert-butyldimethylsilyl chloride to provide intermediate (VI), wherein R a It represents tert-butyl-dimethylsilyl.

[0070] In the second step, R is placed in a suitable solvent, such as THF. a The intermediate (VI), representing tert-butyl-dimethylsilyl, reacts with N-chlorosuccinimide (NCS) to provide intermediate (V).

[0071] Where R a The intermediate (VI) representing hydrogen can be prepared by the method involving intermediate (VII), where Y is as defined above for intermediate (V).

[0072]

[0073] The reaction is conveniently carried out at high temperature in the presence of a strong base, such as sodium hydroxide, in a suitable solvent, such as a mixture of ethanol and water.

[0074] The intermediate of formula (VII) can be prepared by a reaction involving intermediate (VIII).

[0075]

[0076] Y is defined above for the intermediate of equation (V).

[0077] The reaction is conveniently carried out in the presence of trimethylsilyl trifluoromethanesulfonate and oligooxymethane in a suitable solvent such as dichloromethane.

[0078] Intermediate (VIII) can be prepared by a two-step method involving a commercially available intermediate (IX).

[0079]

[0080] Y is defined as in the previous section on intermediate (V).

[0081] The reaction can be conveniently performed according to the methods described in the appended embodiments or according to methods known to those skilled in the art.

[0082] Intermediate of formula (II) can be prepared by chlorination of intermediate of formula (X).

[0083]

[0084] The reaction can be conveniently carried out in a polar solvent mixture such as DMF at room temperature with a chlorinating agent such as N-chlorosuccinimide, or according to any method known to those skilled in the art.

[0085] In the case of obtaining a mixture of products from any of the methods described above for the preparation of compounds according to the invention, the desired product can be separated from it at an appropriate stage by conventional methods, such as preparative HPLC; or column chromatography using, for example, silica and / or alumina in combination with a suitable solvent system.

[0086] In cases where the above-described method for preparing compounds according to the invention produces a mixture of stereoisomers, these isomers can be separated using conventional techniques. Specifically, when a particular enantiomer of the compound of formula (I) is desired, this can be achieved from the corresponding enantiomer mixture using any suitable conventional procedure for resolving enantiomers. Thus, for example, by reacting a mixture of enantiomers of formula (I) (e.g., a racemic mixture) with a suitable chiral compound (e.g., a chiral base), diastereomeric derivatives (e.g., salts) can be obtained. The diastereomeric derivatives can then be separated by any convenient means (e.g., by crystallization), and the desired enantiomer can be recovered, for example, by treatment with acid if the diastereomeric derivative is a salt. In another resolution method, the racemic mixture of formula (I) can be separated using chiral HPLC. Furthermore, if desired, a particular enantiomer can be obtained using a suitable chiral intermediate in one of the above methods. Alternatively, specific enantiomers can be obtained by performing enantiomer-specific enzymatic biotransformation, such as ester hydrolysis using an esterase, followed by purification of only the enantiomerically pure hydrolyzed acid from the unreacted ester enantiomer. When it is desired to obtain specific geometrical isomers of the invention, chromatography, recrystallization, and other conventional separation procedures can also be used with intermediates or end products. Alternatively, undesirable enantiomers can be racemicized to form desired enantiomers in the presence of an acid or base, according to methods known to those skilled in the art or described in the appended examples.

[0087] In any of the above synthetic sequences, it may be necessary and / or necessary to protect sensitive or reactive groups on any molecule involved. This can be achieved using conventional protecting groups, such as those described in the following literature: Protective Groups in Organic Chemistry, ed. J.F.W. McOmie, Plenum Press, 1973; and T.W. Greene and P.G. W. M. Uts, Protective Groups in Organic Synthesis, John Wiley & Sons, 3rd ed., 1999. Protecting groups can be removed at any convenient subsequent stage using methods known in the art.

[0088] The compound of formula (I) according to the invention does not directly activate the dopamine D1 receptor, but enhances the effect of the D1 agonist or the endogenous ligand dopamine of the D1 receptor through an allosteric mechanism, and is therefore a positive allosteric modulator of D1 (D1 PAM).

[0089] Dopamine and other D1 agonists directly activate dopamine D1 receptors.

[0090] Tests have been designed to measure the effects of the compounds according to the invention in the absence of dopamine ("activation test") and in the presence of dopamine ("enhancement test").

[0091] In homogeneous time-resolved fluorescence (HTRF) assays, activation assays measure the stimulation produced by cyclic adenosine monophosphate (cAMP), where the maximum increase in cAMP resulting from increasing the concentration of the endogenous agonist dopamine is defined as 100% activation.

[0092] During testing, the compound of formula (I) according to the invention lacked significant direct agonist effects because it produced less than 20% activation (compared to the maximum response of dopamine) when present at a concentration of 10 μM.

[0093] The enhancement assay measures the ability of a compound to increase cAMP levels produced by low-threshold concentrations of dopamine. The dopamine concentration used ([EC20]) was designed to produce a 20% increase in stimulation compared to the maximum response (100%) observed with increased dopamine concentration. To measure this enhancement, an increased concentration of the compound was incubated with dopamine [EC20], and the enhancement was measured by the increase in cAMP production, with the concentration of the compound producing a 50% increase in cAMP levels being measured.

[0094] When tested in cAMP HTRF assays, the compound of formula (I) according to the invention has shown a pEC50 value greater than about 7.5, indicating that it is a D1 positive allosteric modulator.

[0095] Given GABA A Receptor inhibition is closely associated with epileptic seizures and epilepsy. Therefore, it is desirable to develop compounds that act as positive allosteric modulators of D1 while minimizing these effects.

[0096] When tested in the GABA-A receptor inhibition assay as described herein, it is therefore desirable that, when measuring a 10 μM concentration of compound (I), compound (I) shows less than about 5% GABA. A Percentage of receptor inhibition.

[0097] cAMP HTRF test

[0098] The specific conditions for testing the compounds are described below.

[0099] a. D1 cell culture method

[0100] Cells were cultured at 37°C in a humid atmosphere of 5% CO2. They were cultured in DMEM-F12+GlutaMAX. TM -I medium ( Cells were grown in a medium containing 10% fetal bovine serum (Invitrogen, Merelbeke, Belgium). Lonza, Verviers (Belgium), 400 μg / mL Genomycin 100 IU / mL penicillin and 100 IU / mL streptomycin (Pen-Strep solution) ) LMtk (Ltk-) mouse fibroblasts expressing the dopamine D1 receptor (BioSignal Inc, Montreal, Canada, now Perkin Elmer) were used because they have been shown to bind efficiently and provide robust functional responses (Watts et al, 1995).

[0101] b.cAMP test

[0102] Measurements of intracellular cyclic adenosine monophosphate (cAMP) changes were determined using the CisBio (Codolet, France) HTRF cAMP kinetic assay kit. Using homogeneous time-resolved fluorescence, the assay was based on competition between naturally produced cAMP and cAMP labeled with dye d2. Tracer binding was confirmed by using an anti-cAMP antibody labeled with the cryptic compound. The individual effects (agonists) of the compound were determined by testing in the absence of dopamine, while simultaneously measuring changes in EC2 levels. 20The effect of the compound as a positive allosteric modulator (PAM) was determined in the presence of dopamine at varying concentrations. Cells (20,000 per well) were incubated for 1 hour at room temperature in the presence and absence of dopamine (final 1.1 nM) in 20 μL of HBSS (Lonza, containing 20 mM calcium, magnesium, and HEPES buffer, pH 7.4) in 384 plates containing: isobutylmethylxanthine (Sigma, final 0.1 mM), and varying concentrations of the test compound (typically 10). -9.5 M to 10 -4.5 M). The reaction was then terminated and cells were lysed by adding the d2 detection reagent in lysis buffer (10 μL) and the cavitation compound reagent in lysis buffer (10 μL), according to the manufacturer's instructions. Cells were then incubated at room temperature for 60 minutes and changes in HTRF fluorescence emissivity were determined according to the manufacturer's instructions using an Envision plate reader (Perkin Elmer, Zaventem, Belgium) with laser excitation. All incubations were repeated, and the results were compared with dopamine using a concentration-effect curve. (10) -11 M to 10 -6 M).

[0103] c. Data Analysis

[0104] Data was analyzed using Excel and PRISM (GraphPad software) to obtain pEC using the 4-parameter logarithmic formula (DeLean et al., 1978). 50 Erel, where Erel is the fitted maximum response of the test compound minus the substrate, expressed as a percentage relative to the response obtained with dopamine (defined as 100%).

[0105] pEC of the compound 50 It is the -log10 value of the compound concentration that produces a 50% increase in cAMP levels.

[0106] Erel is a measure of relative potency, defined as the maximum percentage enhancement produced by a compound compared to the maximum response produced by increasing dopamine concentration (Erel = 1 = maximum dopamine response).

[0107] When tested in the above tests, the compound of formula (I) exhibited a pEC50 value of approximately 8.2 and an Erel value of approximately 62%.

[0108] GABA A Automated patch-clamp study of recipient cells

[0109] Using CHO-K1 cells, which stably express human GABA AReceptor α1, β2, and γ2 subunits. Cells were harvested with trypsin and maintained in serum-free medium at room temperature. Cells were washed and resuspended in extracellular solution before testing.

[0110] Patch clamp research

[0111] Automated patch clamp testing (IonFlux) TM HT) to conduct GABA on humans A Experiments on (α1β2γ2) channels. Compounds were tested at three concentrations (0.1, 1, and 10 μM) in three to four cells. Used to record GABA. A The external solution for the current was composed of: 137 mM sodium chloride, 4 mM potassium chloride, 1.8 mM calcium chloride, 1 mM magnesium chloride, 10 mM HEPES, and 10 mM glucose. Both the external and internal solutions were titrated with NaOH or KOH to obtain pH values ​​of 7.35 or 7.3, respectively. The internal pipette solution contained 70 mM potassium fluoride, 60 mM potassium chloride, 70 mM sodium chloride, 5 mM HEPES, 5 mM EGTA, and 4 mM magnesium ATP. The final concentration of the medium used to dilute the compounds was 0.33% DMSO per well. Paeonolide (0.032 to 100 μM) was used as a positive control inhibitor. GABA (15 μM) was used as an agonist. All records were obtained from a holding potential of -60 mV.

[0112] The order of compound addition is as follows: add EC once. 80 GABA concentrations were used to establish a baseline response. Each compound concentration was applied for 30 seconds, followed by the addition of 15 μM GABA for 2 seconds in the presence of the compound. This process was repeated with the next increasing concentration of the compound. The peak inward current in response to the addition of GABA was measured in the presence of a single compound concentration. All compound data were normalized relative to the baseline peak current induced by the addition of 15 μM GABA for 2 seconds.

[0113] In the tests described above, the compound represented by formula (I) exhibited less than approximately 0.1% GABA at a concentration of 10 μM. A The percentage of receptor inhibition was measured at a concentration of 10 μM of compound of formula (I).

[0114] The following examples illustrate the preparation of compounds of formula (I) according to the present invention. Example

[0115] Abbreviations / Common Reagents

[0116] ACN: Acetonitrile

[0117] Salt water: saturated sodium chloride aqueous solution

[0118] nBu: n-Butyl

[0119] tBu: tert-butyl

[0120] COMU: (1-Cyano-2-ethoxy-2-oxoethoxyamino)dimethylamino-morpholino-carbocationic hexafluorophosphate

[0121] DCM: Dichloromethane

[0122] DMAP: 4-Dimethylaminopyridine

[0123] DMF: N,N-dimethylformamide

[0124] DMSO: Dimethyl sulfoxide

[0125] EC 20 / 50 Concentrations that produce a 20% / 50% maximum response

[0126] Erel: Relative effectiveness

[0127] ES + Electrospray positive ionization

[0128] Et: Ethyl

[0129] EtOH: Ethanol

[0130] Et2O: Diethyl ether

[0131] EtOAc: Ethyl acetate

[0132] h: hours

[0133] HPLC: High-performance liquid chromatography

[0134] HTRF: Homogeneous time-resolved fluorescence

[0135] LCMS: Liquid Chromatography-Mass Spectrometry

[0136] MeOH: Methanol

[0137] min.: minutes

[0138] NCS: N-chlorosuccinimide

[0139] NMR: Nuclear Magnetic Resonance

[0140] iPrOH: Isopropanol

[0141] rt: room temperature

[0142] SFC: Supercritical Fluid Chromatography

[0143] TEA: Triethylamine

[0144] THF: Tetrahydrofuran

[0145] TLC: Thin-layer chromatography

[0146] cAMP: Cyclic adenosine monophosphate

[0147] Generate IUPAC names using Biovia Draw version 19.1 (2019) or 20.1 (2020).

[0148] Analytical methods

[0149] All reactions involving air- or moisture-sensitive reagents are carried out under a nitrogen or argon atmosphere using dry solvents and glassware. Commercially available solvents and reagents are generally used without further purification, including anhydrous solvents where appropriate (typically Aldrich Chemical Company's Sure-Seal). TM Products or AcroSeal from ACROS Organics TM Typically, the reaction is tracked by thin-layer chromatography, HPLC, or mass spectrometry.

[0150] LCMS mass spectrometry measurements are performed using the following different methods and equipment:

[0151] - Alkaline LCMS Method 1:

[0152] A QDA Waters simple quadrupole mass spectrometer was used for LCMS analysis. This spectrometer was equipped with an ESI source and a UPLC Acquity Classic with a diode array detector (210 to 400 nm). Data were acquired using full MS scans in positive / negative mode at m / z 70 to 800, with basic elution. For basic elution, reversed-phase separation was performed at 45 °C on a Waters Acquity UPLC BEH C18 1.7 μm (2.1 x 50 mm) column. Gradient elution was performed using H₂O / ACN / ammonium formate (95 / 5 / 63 mg / L) + 100 μL / L NH₄OH (solvent A) and ACN / H₂O / ammonium formate (95 / 5 / 63 mg / L) + 100 μL / L NH₄OH (solvent B). Injection volume: 1 μL. MS complete flow.

[0153] Time (min) A(％) B(％) Flow rate (mL / min) 0 99 1 0.8 0.15 99 1 0.8 1.6 5 95 0.8 1.65 5 95 0.8 2 5 95 0.8 2.05 99 1 0.8 2.75 99 1 0.8

[0154] -Acid LCMS Method 1:

[0155] A QDA Waters simple quadrupole mass spectrometer was used for LCMS analysis. This mass spectrometer was equipped with an ESI source and a UPLC Acquity with a diode array detector (200 to 400 nm). Data were acquired using full MS scans in positive / negative mode at m / z 70 to 800, with acid elution. For acid elution, reversed-phase separation was performed at 45 °C on a Waters Acquity UPLC HSS T3 1.8 μm (2.1 x 50 mm) column. Gradient elution was performed using H₂O / ACN / TFA (95 / 5 / 0.05%) (solvent A) and ACN (solvent B).

[0156] Time (min) A(％) B(％) Flow rate (mL / min) 0 99 1 0.8 0.15 99 1 0.8 1.60 5 95 0.8 1.65 5 95 0.8 2 5 95 0.8 2.05 99 1 0.8 2.75 99 1 0.8

[0157] Some reaction mixtures can be used Separator phase columns (from Biotage), acid columns, or capture and release SPE (solid phase extraction) columns are used for processing. Crude substances can be purified by normal phase chromatography, preparative TLC, (acid or basic) reversed phase chromatography, chiral separation, tritiation, or recrystallization.

[0158] Use a silica gel column (100:200 mesh silica gel or a column used in normal phase column chromatography systems, such as...) Isolera TM Four or Teledyne Isco CombiNormal Normal phase chromatography was performed.

[0159] The product is typically dried under reduced pressure, followed by final analysis and biological testing.

[0160] NMR spectra were recorded on a BRUKER AVANCE III 400MHz-Ultrashield NMR spectrometer, equipped with a Windows 7 professional workstation running Topspin 3.2 software and a 5mm dual resonance broadband probe (PABBI). 1 H / 19 F-BB Z-GRD Z82021 / 0075) or 1mm triple resonance probe (PATXI) 1 H / D- 13 C / 15 N Z-GRD Z868301 / 004).

[0161] Chemical shifts are signals generated by residual protons in deuterated solvents (DMSO-d6, MeOH-d4, or CDCl3). Chemical shifts are provided in parts per million (ppm) and coupling constants (J) in Hertz (Hz). Spin multiplicity is provided as broad (br), singlet (s), doublet (d), triplet (t), quartet (q), and multiplicity (m).

[0162] All final products were analyzed by LCMS in both basic and acid modes as follows:

[0163] - Alkaline LCMS Method 2:

[0164] A QDA Waters simple quadrupole mass spectrometer was used for LCMS analysis. This spectrometer was equipped with an ESI source and a UPLC Acquity Classic with a diode array detector (210 to 400 nm). Data were acquired using full MS scans in positive / negative mode at m / z 70 to 800, with basic elution. For basic elution, reversed-phase separation was performed at 45 °C on a Waters Acquity UPLC BEH C18 1.7 μm (2.1 x 100 mm) column. Gradient elution was performed using H₂O / ACN / ammonium formate (95 / 5 / 63 mg / L) + 100 μL / L NH₄OH (solvent A) and ACN / H₂O / ammonium formate (95 / 5 / 63 mg / L) + 100 μL / L NH₄OH (solvent B). Injection volume: 1 μL. MS complete flow.

[0165] Time (min) A(％) B(％) Flow rate (mL / min) 0 99 1 0.4 0.8 99 1 0.4 5.30 0 100 0.4 5.35 0 100 0.5 7.30 0 100 0.5 7.35 99 1 0.4 9 90 1 0.4

[0166] -Acid LCMS Method 2:

[0167] A QDA Waters simple quadrupole mass spectrometer was used for LCMS analysis. This mass spectrometer was equipped with an ESI source and a UPLC Acquity Hclass with a diode array detector (210 to 400 nm). Data were acquired using full MS scans in positive / negative mode at m / z 70 to 800, with acid elution. For acid elution, reversed-phase separation was performed at 45 °C on a Waters Acquity UPLC HSS T3 1.8 μm (2.1 x 100 mm) column. Gradient elution was performed using H₂O / ACN / TFA (95 / 5 / 0.05%) (solvent A) and ACN (solvent B).

[0168] Time (min) A(％) B(％) Flow rate (mL / min) 0 99 1 0.4 0.8 99 1 0.4 5.3 5 95 0.4 5.35 5 95 0.5 7.3 5 95 0.5 7.35 99 1 0.4 9 99 1 0.4

[0169] 1. Preparation of intermediate (II)-2-(3,5-dichloro-1H-indazol-4-yl)acetic acid

[0170]

[0171] At room temperature, NCS (1.5 g, 11 mmol) was added fractionally to a DMF (10 mL) solution of 2-(5-chloro-1H-indazole-4-yl)acetic acid X (CAS: 1904662-08-3, WO2016055479, 2.1 g, 10 mmol) and the mixture was stirred overnight. The reaction mixture was quenched dropwise by adding 100 mL of water. The product precipitated after stirring over 1 h. The solid was filtered and washed twice with the mother liquor phase and twice with water (50 mL). The solid was then dried under reduced pressure at 45 °C overnight, providing 2-(3,5-dichloro-1H-indazole-4-yl)acetic acid (2.0 g, 7.62 mmol, 93% purity, 76% yield), which was used in subsequent steps without further purification.

[0172] Acid LCMS Method 2 (ES) + ): 245 / 247 / 249 (M+H) +

[0173] 1 H NMR (400MHz, DMSO-d6): δ13.52 (s, 1H), 7.52 (d, J=8.9Hz, 1H), 7.47 (d, J=8.9Hz, 1H), 4.21 (s, 2H)

[0174] 2. Preparation of compound (I)

[0175] 2-(3,5-Dichloro-1-methyl-indazol-4-yl)-1-[(1S,3R)-3-(hydroxymethyl)-5-(1-hydroxy-1-methyl-ethyl)-1-methyl-3,4-dihydro-1H-isoquinoline-2-yl] ethyl ketone

[0176]

[0177] 2.1. Preparation of intermediate (IX).

[0178] (2R)-2-amino-3-(2-bromophenyl)prop-1-ol-a6

[0179] (2R)-2-amino-3-(2-bromophenyl)propionic acid a5 (34.0 kg, 139 mol) and THF (238 L) were added to the reactor. Sodium borohydride (15.6 kg, 413 mol) was slowly added at 20–30 °C. Iodine (35.3 kg, 139 mol) in anhydrous THF (20.0 L) solution was slowly added at 0–10 °C, and the reaction mixture was stirred at 70 °C for 12 h. The reaction was quenched at 0 °C with methanol (70.0 L) and heated to 80 °C for 30 min. The mixture was cooled, concentrated under reduced pressure, and the residue was suspended in NaOH (30.0 L, 2N) and then filtered. The filter cake was dried under reduced pressure, providing (2R)-2-amino-3-(2-bromophenyl)prop-1-ol a6 as a white solid (31.0 kg, 135 mol, 96.7% yield), which was used in subsequent steps without further purification.

[0180] 1 H NMR (400MHz, CDCl3) δ7.57 (d, J=7.7Hz, 1H), 7.21-7.29 (m, 2H), 7.07-7.15 (m, 1H), 3.66 (dd, J=10.5, 3.6Hz, 1H), 3.41 (d d, J=10.5, 7.2Hz, 1H), 3.18-3.29 (m, 1H), 2.95 (dd, J=13.5, 5.5Hz, 1H), 2.70 (dd, J=13.5, 8.2Hz, 1H), 1.51-1.91 (m, 3H).

[0181] 2.2. Preparation of formula (VIII) intermediate.

[0182] (4R)-4-[(2-bromophenyl)methyl]oxazolidin-2-one-a7

[0183] (2R)-2-amino-3-(2-bromophenyl)prop-1-ol a6 (31.0 kg, 135 mol) and dichloromethane (220 L) were added to the reactor. Triphosgene (13.9 kg, 47.1 mol) was added at room temperature, followed by the slow addition of N,N-diisopropylethylamine (39.1 kg, 303 mol) at 0–10 °C. The reaction mixture was stirred at 0–10 °C for 1 h, then washed twice with water (50.0 L), dried with anhydrous sodium sulfate, and filtered to provide (4R)-4-[(2-bromophenyl)methyl]oxazolidin-2-one a7, a solution in dichloromethane, which was used directly in subsequent steps.

[0184] 2.3. Preparation of intermediates (VII).

[0185] (10aR)-9-bromo-1,5,10,10a-tetrahydrooxazolo[3,4-b]isoquinoline-3-one a8

[0186] A solution of (4R)-4-[(2-bromophenyl)methyl]oxazolidin-2-one a7 (135 mol) in dichloromethane (220 L) was added to the reactor and cooled to 0–5 °C. Trimethylsilyl trifluoromethanesulfonate (35.9 kg, 162 mol) and polyoxymethylene (13.3 kg, 148 mol) were added at 0–5 °C, followed by stirring at 15–20 °C for 2 h. Water (170 L) was added to the mixture, which was then extracted twice with dichloromethane (50.0 L). The organic layer was dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. A mixture of petroleum ether:ethyl acetate (1:1, 45.0 L) was added, and the mixture was stirred at room temperature for 6 h and filtered. The solid was dried to give (10aR)-9-bromo-1,5,10,10a-tetrahydrooxazolo[3,4-b]isoquinoline-3-one a8, which was a creamy white solid (29.0 kg, 80.2% yield).

[0187] 1 H NMR (400MHz, CDCl3) δ7.45-7.52 (m, 1H), 7.08-7.14 (m, 2H), 4.83 (d, J=17.0Hz, 1H), 4.62 (t, J=8.4Hz, 1H), 4.36 (d, J=17 .0Hz, 1H), 4.21 (dd, J=8.6, 4.9Hz, 1H), 3.91-3.99 (m, 1H), 3.25 (dd, J=16.3, 4.2Hz, 1H), 2.67 (dd, J=16.1, 11.0Hz, 1H).

[0188] 2.4. Preparation of intermediates (VI)

[0189] 2.4.1. [(3R)-5-bromo-1,2,3,4-tetrahydroisoquinoline-3-yl]methanol a9

[0190] Ethanol (120 L) and water (60.0 L) were mixed and added to the reactor. (10aR)-9-bromo-1,5,10,10a-tetrahydrooxazolo[3,4-b]isoquinoline-3-one a8 (29.7 kg, 111 mol) was added, followed by slow addition of sodium hydroxide (13.3 kg, 332 mol) at 15–20 °C. The reaction mixture was stirred at 90 °C for 2 h and then cooled to room temperature. Water (300 L) was added to the mixture, which was then centrifuged. The centrifuged cake was dried in a circulating oven, yielding [(3R)-5-bromo-1,2,3,4-tetrahydroisoquinoline-3-yl]methanol a9, a white solid (23.7 kg, 88.3% yield), which was used in subsequent steps without further purification.

[0191] 1H NMR (400MHz, CDCl3) δ7.37-7.47 (m, 1H), 6.95-7.08 (m, 2H), 4.00-4.10 (m, 2H), 3.85 (dd, J=10.9, 3.7Hz, 1H), 3.57 (dd, J=10. 9, 7.9Hz, 1H), 3.06 (ddt, J=11.3, 7.6, 4.1, 4.1Hz, 1H), 2.79 (dd, J=17.1, 4.4Hz, 1H), 2.40 (dd, J=17.1, 10.9Hz, 1H), 1.93 (br s, 2H).

[0192] 2.4.2. [(3R)-5-bromo-1,2,3,4-tetrahydroisoquinoline-3-yl]methoxy-tert-butyl-dimethyl-silane a10

[0193] [(3R)-5-bromo-1,2,3,4-tetrahydroisoquinoline-3-yl]methanol a9 (23.7 kg, 97.8 mol) and dichloromethane (240 L) were added to the reactor. DMAP (120 g, 0.98 mol) and imidazole (13.3 kg, 196 mol) were added. Tert-butyldimethylsilyl chloride (TBSCl) (17.7 kg, 117 mol) was slowly added at 15-20 °C, and the mixture was stirred for 12 h. Ammonium chloride (100 L) was then added to the mixture. The organic phase was separated, washed with water (50.0 L), dried with anhydrous sodium sulfate, filtered, and concentrated under reduced pressure to provide [(3R)-5-bromo-1,2,3,4-tetrahydroisoquinoline-3-yl]methoxy-tert-butyl-dimethyl-silane a10, a yellow oil (37.6 kg, 86% purity, 93% yield), which was used in subsequent steps without further purification.

[0194] 1 H NMR (400MHz, CDCl3) δ7.36-7.45 (m, 1H), 7.01 (d, J=4.6Hz, 1H), 4.01-4.13 (m, 2H), 3.84 (dd, J=9.9, 3.7Hz, 1H), 3.64 (dd, J=9.8, 7.2Hz, 1H) , 2.96-3.08 (m, 1H), 2.75 (dd, J=17.0, 4.2Hz, 1H), 2.44 (dd, J=17.0, 10.8Hz, 1H), 1.76-2.20 (m, 2H), 0.89-0.97 (m, 9H), 0.08-0.14 (m, 6H).

[0195] 2.5. Preparation of intermediate (V).

[0196] [(3R)-5-bromo-1,2,3,4-dihydroisoquinoline-3-yl]methoxy-tert-butyl-dimethyl-silane a11: [(3R)-5-bromo-1,2,3,4-tetrahydroisoquinoline-3-yl]methoxy-tert-butyl-dimethyl-silane a10 (3.42 kg, 8.31 mol) and THF (30.0 L) were added to the reactor. N-chlorosuccinimide (NCS) (1.17 kg, 8.73 mol) was slowly added at room temperature, and the mixture was stirred at 25 °C for 30 min. A solution of KOH (1.52 kg, 27.1 mol) in anhydrous methanol (7.00 L) was slowly added at room temperature, and the reaction was stirred at 25 °C for 1 h. The reaction was quenched with water (10.0 L) and extracted with petroleum ether:ethyl acetate (1:2, 5.00 L). The organic layer was separated, washed with brine (10.0 L), dried over anhydrous sodium sulfate, and filtered. The overall procedure was performed in parallel on 10 batches of the same size, and the 10 reaction filtrates were combined and concentrated under reduced pressure to provide [(3R)-5-bromo-3,4-dihydroisoquinoline-3-yl]methoxy-tert-butyl-dimethyl-silane a11, a brown oil (28.0 kg, crude), which was used in subsequent steps without further purification.

[0197] 1 H NMR (400MHz, CDCl3) δ8.24 (d, J=2.6Hz, 1H), 7.58 (dd, J=7.8, 1.2Hz, 1H), 7.12-7.25 (m, 2H), 4.03 (dd, J=9.5, 4.0Hz, 1H), 3.67-3.77 (m, 2H), 3.07 (dd, J=17.0, 6.2Hz, 1H), 2.68 (dd, J=17.1, 10.9Hz, 1H), 0.88-0.91 (m, 9H), 0.07 (d, J=1.5Hz, 6H).

[0198] 2.6. Preparative (IV) Intermediates

[0199] 2.6.1. [(1S,3R)-5-bromo-1-methyl-1,2,3,4-tetrahydroisoquinoline-3-yl]methoxy-tert-butyl-dimethyl-silane (IVa)

[0200] [(3R)-5-bromo-3,4-dihydroisoquinoline-3-yl]methoxy-tert-butyl-dimethylsilane a11 (3.10 kg, 8.75 mol) and THF (20.0 L) were added to the reactor. The mixture was cooled to 0 °C and methyl magnesium chloride (3 M, 11.6 L) was added. The mixture was stirred at 20 °C for 12 h. The reaction was quenched with a saturated ammonium chloride solution. The phase separation and aqueous layer were extracted twice with petroleum ether:ethyl acetate (3:1, 5.00 L). The combined organic phases were washed with brine (10.0 L), dried over anhydrous sodium sulfate, and filtered. This overall procedure was performed in parallel on nine batches of the same scale, and the nine reaction filtrates were combined and concentrated under reduced pressure. The crude mixture was purified by silica gel chromatography with petroleum ether:ethyl acetate (10:1) to provide [(1S,3R)-5-bromo-1-methyl-1,2,3,4-tetrahydroisoquinoline-3-yl]methoxy-tert-butyl-dimethyl-silane (IVa), a brown oil (4.60 kg, 99.7% purity, 15.7% yield).

[0201] 1 H NMR (400MHz, DMSO-d6) δ7.41 (dd, J=7.7, 0.9Hz, 1H), 7.12-7.18 (m, 1H), 7.03-7.11 (m, 1H), 4.12 (q, J=6.8H z, 1H), 3.62 (d, J=5.7Hz, 2H), 3.07-3.17 (m, 1H), 2.67-2.76 (m, 1H), 2.26 (dd, J=16.9, 10.0Hz, 1H), 2.12 (br s, 1H), 1.32 (d, J=6.8Hz, 3H), 0.84-0.93 (m, 9H), 0.07 (d, J=0.9Hz, 6H).

[0202] 2.6.2. (1S,3R)-5-bromo-3-[[tert-butyl(dimethyl)silyl]oxymethyl]-1-methyl-3,4-dihydro-1H-isoquinoline-2-carboxylic acid tert-butyl ester (IVb)

[0203] [(1S,3R)-5-bromo-1-methyl-1,2,3,4-tetrahydroisoquinoline-3-yl]methoxy-tert-butyl-dimethylsilane (IVa) (1.85 kg, 4.99 mol) and dichloromethane (13.0 L) were added to the reactor. N,N-diisopropylethylamine (1.94 kg, 14.9 mol) and ditert-butyl dicarbonate (1.14 kg, 5.24 mol) were added at room temperature, and the mixture was stirred for 12 h. The reaction mixture was washed twice with saturated ammonium chloride solution (10.0 L), and the organic layer was dried over anhydrous sodium sulfate and filtered. This overall procedure was performed in parallel for two batches of the same scale, and the two reaction filtrates were combined and concentrated under reduced pressure. The crude mixture was purified by silica gel chromatography with petroleum ether:ethyl acetate (30:1) to provide (1S,3R)-5-bromo-3-[[tert-butyl(dimethyl)silyl]oxymethyl]-1-methyl-3,4-dihydro-1H-isoquinoline-2-carboxylic acid tert-butyl ester (IVb), a yellow oil (4.00 kg, 99.5% purity, 85.2% yield).

[0204] 1 H NMR (400MHz, DMSO-d6) δ7.50 (d, J=7.9Hz, 1H), 7.22 (br d, J=6.7Hz, 1H), 7.06-7.18 (m, 1H), 4.84 (br s, 1H), 4.12 (br s, 1H), 3.46 (br d, J=15.4Hz, 2H), 2.94 (brdd, J=15.8, 5.2Hz, 1H), 2.71 (br t, J=9.5Hz, 1H), 1.45 (s, 9H), 1.28 (br s, 3H), 0.81 (s, 9H), -0.08 (s, 6H).

[0205] 2.6.3. (1S,3R)-3-[[tert-butyl(dimethyl)silyl]oxymethyl]-5-(1-hydroxy-1-methyl-ethyl)-1-methyl-3,4-dihydro-1H-isoquinoline-2-carboxylic acid tert-butyl ester (IVc)

[0206] Anhydrous THF solution (0.5 M) of (1S,3R)-5-bromo-3-[[tert-butyl(dimethyl)silyl]oxymethyl]-1-methyl-3,4-dihydro-1H-isoquinoline-2-carboxylic acid tert-butyl ester (IVb) (42.5 g, 90.3 mmol) and a commercially available n-butyllithium solution in hexane (1.6 M) were pumped at 6.0 mL / min (1.0 equivalent) and 2.46 mL / min (1.3 equivalent), respectively, and mixed in a glass microchip cooled at -40 °C. The mixture was then pumped through reaction zone 1 of the microchip (0.3 mL) and combined with anhydrous acetone solution (13.5 M) pumped at 6.0 mL / min (27 equivalent). The resulting stream was then passed through reaction zone 2 of the microchip (0.7 mL) at -40 °C. Finally, the entire stream exiting the reactor was collected and quenched in a saturated aqueous ammonium chloride solution at room temperature. When all the feed solution was consumed, a bilayer reaction mixture was obtained. The aqueous layer was separated from the organic layer and then extracted twice with ethyl acetate. The combined organic layers were washed with brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. A yellow oil (46.5 g) was obtained and purified by SFC chromatography on a GreenSep Nitro column (10 μm, 5 x 22.3 μm, eluent 98% CO2 / 2% EtOH). The solvent was removed under reduced pressure to give a white solid, (1S,3R)-3-[[tert-butyl(dimethyl)silyl]oxymethyl]-5-(1-hydroxy-1-methyl-ethyl)-1-methyl-3,4-dihydro-1H-isoquinoline-2-carboxylic acid tert-butyl ester (IVc) (25 g, 56 mmol, 62% yield).

[0207] UPLC-MS alkalinity: 1 peak @ 3.83 min (ES+): 350 (M-Boc+H) + ,332(M-Boc-H2O+H) + 100% purity.

[0208] 1H NMR (400MHz, DMSO-d6) δ7.44 (d, J=7.9Hz, 1H), 7.19 (dt, J=8.1, 5.2Hz, 1H), 7.09 (t, J=9.0Hz, 1H) , 4.99 (s, 1H), 4.87 (dq, J=13.4, 6.4Hz, 1H), 4.11 (s, 1H), 3.96 (t, J=14.9Hz, 1H), 3.48 (dd, J=9.4 , 4.1Hz, 1H), 2.98 (dd, J=16.5, 5.0Hz, 1H), 2.89 (t, J=9.6Hz, 1H), 1.65 (s, 3H), 1.58 (s, 3H), 1.55 (d, J=2.5Hz, 9H), 1.34 (dd, J=20.5, 6.6Hz, 3H), 0.90 (s, 9H), 0.08 (d, J=7.2Hz, 3H), -0.00 (s, 3H).

[0209] 2.7. Preparation of intermediate (III) tert-butyl-dimethyl-[[(1S,3R)-1-methyl-5-(1-methyl-1-trimethylsilyloxy-ethyl)-1,2,3,4-tetrahydroisoquinoline-3-yl]methoxy]silane

[0210] (1S,3R)-3-[[tert-butyl(dimethyl)silyl]oxymethyl]-5-(1-hydroxy-1-methyl-ethyl)-1-methyl-3,4-dihydro-1H-isoquinoline-2-carboxylic acid tert-butyl ester (IVc) (148 g, 87% purity, 287 mmol) was dissolved in 1000 mL of dichloromethane and transferred to a 2 L double-walled reactor. 2,6-Lutidine (100 mL, 860 mmol) was added, and the sleeve temperature was set to -2 °C. Trimethylsilyl trifluoromethanesulfonate (154 g, 129 mL, 692 mmol) was added via a feeding funnel over 40 minutes. Two hours after the start of the addition, the reaction was quenched by adding 650 mL of citric acid aqueous solution (1 M) to bring the mixture temperature back to 20 °C. One hour after the start of quenching, the layers were separated. The organic layer was washed twice with 350 mL of citric acid aqueous solution (1 M). The organic layer was stirred with 750 mL of sodium carbonate aqueous solution (10% w / w) for 10 minutes, and then the layers were separated. The organic layer was dried on anhydrous sodium sulfate. The organic layer was then filtered, and the filtrate was concentrated under reduced pressure at 40 °C to provide a yellow oil (128 g), which was tert-butyl-dimethyl-[[(1S,3R)-1-methyl-5-(1-methyl-1-trimethylsilyloxy-ethyl)-1,2,3,4-tetrahydroisoquinoline-3-yl]methoxy]silane (III), which was used in subsequent steps without further purification.

[0211] 1H NMR (400MHz, CDCl3) δ7.19 (d, J=7.7Hz, 1H), 7.07 (t, J=7.7Hz, 1H), 7.00 (d, J=7.6Hz, 1H), 4.24 (q, J= 6.8Hz, 1H), 3.75 (dd, J=9.7, 4.4Hz, 1H), 3.60 (dd, J=9.7, 7.0Hz, 1H), 3.54 (dd, J=16.3, 3.5Hz, 1H), 3. 15 (ddt, J=10.9, 7.4, 4.0Hz, 1H), 2.52 (ddt, J=16.3, 10.9Hz, 1H), 1.66 (d, J=14.6Hz, 6H), 1.52-1.43 (m , 3H), 0.92 (q, J=1.2Hz, 9H), 0.14 (q, J=1.2Hz, 2H), 0.09 (d, J=1.1Hz, 6H), 0.00 (q, J=1.2, 0.8Hz, 9H).

[0212] 2.8. Preparation of compound (I) 2-(3,5-dichloro-1H-indazol-4-yl)-1-[(1S,3R)-3-(hydroxymethyl)-5-(1-hydroxy-1-methyl-ethyl)-1-methyl-3,4-dihydro-1H-isoquinoline-2-yl] ethyl ketone

[0213] To a solution of 2-(3,5-dichloro-1H-indazol-4-yl)acetic acid (II) (200 mg, 0.82 mmol) in DMF (2.00 mL), tert-butyl-dimethyl-[[(1S,3R)-1-methyl-5-(1-methyl-1-trimethylsilyloxy-ethyl)-1,2,3,4-tetrahydroisoquinoline-3-yl]methoxy]silane (413 mg, 0.98 mmol), DIPEA (405 μL, 2.44 mmol), and COMU (398 mg, 0.90 mmol) were added to rt. The resulting reaction mixture was stirred for 1 hour. The reaction mixture was diluted with EtOAc and water, and the layers were separated. The aqueous layer was extracted with EtOAc (3x). The combined organic layers were washed with water (3x), saturated NaHCO3 aqueous solution, and brine, dried on Na2SO4, filtered, and concentrated to provide a brown residue. The crude residue was filtered through silica (25 g) SFAR silica gel column, 100:0 to 0:100 heptane:EtOAc gradient), providing 1-[(1S,3R)-3-[[tert-butyl(dimethyl)silyl]oxymethyl]-1-methyl-5-(1-methyl-1-trimethylsilyloxy-ethyl)-3,4-dihydro-1H-isoquinolin-2-yl]-2-(3,5-dichloro-1H-indazol-4-yl)acetone and 1-[(1S,3R)-3- A (1:1) mixture of [[tert-butyl(dimethyl)silyl]oxymethyl]-5-(1-hydroxy-1-methyl-ethyl)-1-methyl-3,4-dihydro-1H-isoquinolin-2-yl]-2-(3,5-dichloro-1H-indazol-4-yl)acetone, a yellow oil (320 mg), was dissolved directly in THF (3 mL) at room temperature, followed by the addition of TBAF (1.02 mL, 1.02 mmol). The resulting reaction mixture was stirred at room temperature for 1 hour. The reaction mixture was diluted with EtOAc and water, the layers were separated, the organic layer was washed with water (3x), dried on Na2SO4, filtered, and concentrated to provide a colorless oil. The crude product was purified by reversed-phase rapid chromatography (Biotage Isolera Four) under basic conditions (partially 1.0 g, C18 SNAP 60 g gel column, gradient of 20% to 100% water / NH4OH in CH3CN) to provide 2-(3,5-dichloro-1H-indazol-4-yl)-1-[(1S,3R)-3-(hydroxymethyl)-5-(1-hydroxy-1-methyl-ethyl)-1-methyl-3,4-dihydro-1H-isoquinoline-2-yl]acetone (I) (37.0 mg, 0.08 mmol, 10% yield), as a white solid. Basic LCMS Method 2: 1 peak @ 3.72 min (ES). + ): 462[M+H] + 98% purity. Acid LCMS method 2: 1 peak @ 4.14 min (ES)+ ): 462 [M+H] + , 98% purity.

[0214] 1 H NMR (400 MHz, DMSO-d6) δ 7.54 - 7.49 (m, 1H), 7.49 - 7.43 (m, 1H), 7.40 (dd, J = 7.5, 1.8 Hz, 0.3H), 7.35 (dd, J = 7.9, 1.3 Hz, 0.7H), 7.23 - 7.04 (m, 2H), 5.31 (q, J = 6.6 Hz, 0.3H), 5.14 (s, 0.3H), 5.12 (s, 0.7H), <5.05 (q, J = 6.4 Hz, 0.7H)>, 4.96 (t, J = 5.5 Hz, 0.7H), 4.64 - 4.30 (m, 3H), 4.17 (q, J = 5.4 Hz, 0.3H), 4.10 - 3.98 (m, 1H), 3.30 (tt, J = 9.8, 5.0 Hz, 1H), 3.05 (dd, J = 16.1, 4.4 Hz, 1H), 2.97 (p, J = 7.8, 6.3 Hz, 1H), 1.57 (d, J = 9.6 Hz, 6H), 1.53 (s, 1H), 1.24 (d, J = 6.5 Hz, 2H). Note: There seems to be a formatting issue in the original text for the part "5.05(q, J = 6.4 Hz, 0.7H)" which was missing an opening angle bracket "<" in the original. It has been added in the translation for better readability and to follow the NMR chemical shift format. If this is not an error in the original, please correct the translation accordingly.

Claims

1. 2-(3,5-dichloro-indazol-4-yl)-1-[(1S,3R)-3-(hydroxymethyl)-5-(1-hydroxy-1-methyl-ethyl)-1-methyl-3,4-dihydro-1H-isoquinolin-2-yl] ethyl ketone of formula (I), or a pharmaceutically acceptable salt thereof.

2. Use of a compound of formula (I) according to claim 1 or a pharmaceutically acceptable salt thereof for the preparation of a medicament for the treatment and / or prevention of diseases and / or disorders in which the D1 receptor functions.

3. Use of a compound of formula (I) according to claim 1 or a pharmaceutically acceptable salt thereof for the preparation of a medicament for the treatment and / or prevention of cognitive and negative symptoms in schizophrenia, cognitive impairment related to neuroleptic treatment, mild cognitive impairment (MCI), impulsive behavior, attention deficit hyperactivity disorder (ADHD), Parkinson's disease and other movement disorders, dystonia, Parkinson's dementia, Huntington's disease, Lewy body dementia, Alzheimer's disease, drug addiction, sleep disorders, apathy, traumatic spinal cord injury or neuropathic pain.

4. A pharmaceutical composition comprising a compound of formula (I) as defined in claim 1 or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable carrier thereof in combination therewith.

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