Methods of making targeted degrader ligands and linkers

Abstract

The present application relates to the preparation of targeted degrading ligands and linking groups, in particular to the preparation of compound 3 and compound 4, and their use as intermediates in the preparation of targeted protein degraders.

Description

Process for the preparation of targeted degrader ligands and linkers TECHNICAL FIELD

[0001] The present application relates to a process for the preparation of targeted degrader ligands and linkers, in particular to a process for the preparation of Compound 3 and Compound 4. BACKGROUND

[0002] The following background description is not an indication that it is prior art to the present application.

[0003] Treating diseases by degrading target pathogenic proteins is a new model in the field of drug research and development, among which the Proteolysis Targeting Chimera (PROTAC) technology is a representative technology for tumor targeted therapy. PRTOAC is a bifunctional molecule composed of 3 parts, including a ligand that binds to the target protein, a ligand that binds to the E3 ubiquitin protein ligase, and a linker connecting them.

[0004] International patent application PCT / CN2023 / 139101 provides a series of PROTAC chimeric compounds with HPK1 inhibition / degradation activity, and specifically provides a preparation method of compounds C195 and C196 in Examples 59 and 60. The preparation methods of the two compounds use basically the same reaction route, as shown below:

[0005] Synthetic route for preparing C195

[0006] Synthetic route for preparing C196

[0007] However, it has been found that these preparation methods have some shortcomings that need to be improved. Developing and using new preparation intermediates can be a way to improve. SUMMARY

[0008] In a first aspect, the present application provides a process for the preparation of Compound 3, i.e. tert-butyl 4-((1-(5-(4,4,5,5-tetramethyl-1,3,2-dioxaborinan-2-yl)pyridin-2-yl)piperidin-4-yl)methyl)piperidine-1- carboxylate, which is an intermediate for the degradation of proteins in the ubiquitin-proteasome system,

[0009] The process comprises Step A, Step B, Step C and Step D, wherein each of Step A, Step B, Step C and Step D is as shown in Reaction Scheme 1A below and as described hereinafter:

[0010] Reaction Scheme 1A

[0011] wherein,

[0012] - Step A comprises obtaining compound 3-A from compound 3-RM1 and compound 3-RM2;

[0013] - Step B comprises subjecting compound 3-A to a reduction reaction to obtain compound 3-B;

[0014] - Step C comprises reacting compound 3-B and compound 3-RM3 to obtain compound 3-C;

[0015] - Step D comprises reacting compound 3-C with bis(pinacolato)diboron (BDP) to obtain said compound 3.

[0016] In some embodiments, the present application provides a process as described hereinabove, wherein said Step A comprises subjecting compound 3-RM1, a tetrahydrofuran (THF) solution of 9-borabicyclo[3,3,1]-nonane (9-BBN) and compound 3-RM2 to a reaction catalyzed by a palladium catalyst in the presence of an aprotic polar solvent, water and an inorganic base to obtain compound 3-A.

[0017] In some embodiments, said Step A is carried out under an inert atmosphere, preferably under a nitrogen atmosphere.

[0018] In some embodiments, said Step A comprises:

[0019] (1) mixing said THF solution of 9-BBN and compound 3-RM1 under said inert atmosphere, followed by removing THF at temperature T1; and

[0020] (2) subjecting the mixture obtained from step (1) and compound 3-RM2 to a reaction catalyzed by said palladium catalyst in the presence of said aprotic polar solvent, said water and said inorganic base at temperature T2 to obtain compound 3-A.

[0021] In some embodiments, said Step A comprises:

[0022] (1) mixing a THF solution of compound 9-BBN and compound 3-RM1 under nitrogen protection, followed by removing THF by concentration (e.g. under reduced pressure) at temperature T1; and

[0023] (2) subjecting the mixture obtained from step (1) and said aprotic polar solvent, said water, said inorganic base, compound 3-RM2 and said palladium catalyst to a reaction at temperature T2 under a nitrogen atmosphere to obtain compound 3-A.

[0024] In some embodiments, the present application provides the method as described above, wherein the step B comprises subjecting compound 3-A to a reduction reaction in the presence of palladium on carbon under a hydrogen atmosphere to obtain compound 3-B.

[0025] In some embodiments, the step B comprises subjecting an acetic acid solution of compound 3-A to a reduction reaction in the presence of palladium on carbon under a hydrogen atmosphere to obtain compound 3-B.

[0026] In some embodiments, the reduction reaction is carried out at a temperature T3.

[0027] In some embodiments, the step B comprises subjecting an acetic acid solution of compound 3-A to a reduction reaction in the presence of palladium on carbon under a hydrogen atmosphere at a temperature T3 to obtain compound 3-B.

[0028] In some embodiments, the present application provides the method as described above, wherein the step C comprises reacting compound 3-B with compound 3-RM3 in the presence of a polar solvent and an inorganic base to obtain compound 3-C.

[0029] In some embodiments, the step C is carried out under an inert atmosphere, preferably under a nitrogen atmosphere.

[0030] In some embodiments, the reaction in the step C is carried out at a temperature T4.

[0031] In some embodiments, the step C comprises reacting compound 3-B with compound 3-RM3 in the presence of a polar solvent and an inorganic base under a nitrogen atmosphere at a temperature T4 to obtain compound 3-C.

[0032] In some embodiments, the present application provides the method as described above, wherein the step D comprises reacting compound 3-C with BDP in the presence of an alkali metal acetate and a palladium catalyst in toluene to obtain compound 3.

[0033] In some embodiments, the step D is carried out under an inert atmosphere, preferably under a nitrogen atmosphere.

[0034] In some embodiments, the alkali metal acetate in the step D is sodium acetate or potassium acetate. In some embodiments, the alkali metal acetate in the step D is potassium acetate.

[0035] In some embodiments, the reaction in the step D is carried out at a temperature T5.

[0036] In some embodiments, the step D comprises reacting compound 3-C with BDP in the presence of potassium acetate and a palladium catalyst in toluene under a nitrogen atmosphere at a temperature T5 to obtain compound 3.

[0037] In a second aspect, the present application provides a method of preparing compound 3, i.e., tert-butyl 4-((l-(5-(4,4,5,5-tetramethyl-l,3,2-dioxaborolan-2-yl)pyridin-2-yl)piperidin-4- yl)methyl)piperidine-l-carboxylate,

[0038] The method comprises steps A, B, C, and D, wherein steps A, B, C, and D are each as shown in Reaction Scheme 1 below and as described hereinafter:

[0039] Reaction Scheme 1

[0040] wherein,

[0041] - Step A comprises adding compound 3-RM1 to a THF solution of compound 9-BBN, adding compound 3-RM2, a polar solvent, and an inorganic base and catalyzing with a palladium catalyst to react to obtain compound 3-A;

[0042] - Step B comprises adding palladium on carbon to a solution of compound 3-A and reacting to obtain compound 3-B;

[0043] - Step C comprises adding a polar solvent, an inorganic base, and compound 3-RM3 to a solution of compound 3-B and reacting to obtain compound 3-C;

[0044] - Step D comprises adding compound 3-C, potassium acetate, BDP, a palladium catalyst, and toluene and reacting to obtain the compound 3.

[0045] The present application further provides embodiments of the method of preparation according to the first and second aspects above, as described hereinafter.

[0046] In some embodiments, the steps A, B, C, D optionally independently comprise a work-up selected from one or more of stirring, temperature control, concentration, distillation, extraction, filtration, washing, recrystallization, trituration, and drying.

[0047] In some embodiments, the step A comprises: adding compound 9-BBN (0.5M THF solution) into a reaction kettle under nitrogen protection; adding compound 3-RM1 into the reaction kettle; controlling the temperature of the reaction kettle at T1, stirring and concentrating under reduced pressure to remove THF; adding the aprotic polar solvent, the water, the inorganic base, compound 3-RM2, the palladium catalyst into the reaction kettle, controlling the temperature of the reaction kettle at T2, and stirring under nitrogen atmosphere; adding water and methyl tert-butyl ether (MTBE) into the reaction kettle, separating the layers, extracting the aqueous phase with MTBE, washing the combined organic phase, and concentrating the combined organic phase without distillate; adding glacial acetic acid into the reaction kettle, stirring to dissolve the clear solution to obtain compound 3-A.

[0048] In some embodiments, the step B comprises: adding an acetic acid solution of compound 3-A into a reaction kettle under nitrogen protection; adding palladium-carbon into the reaction kettle; introducing hydrogen into the reaction kettle at 1.5 MPa, controlling the temperature of the reaction kettle at T3, and stirring; after depressurizing, cooling to room temperature, filtering, washing the filter cake with glacial acetic acid to obtain compound 3-B.

[0049] In some embodiments, the step C comprises: adding an acetic acid solution of compound 3-B into a reaction kettle under nitrogen protection; concentrating to dryness, adding acetonitrile to distill twice; adding the polar solvent, the inorganic base, compound 3-RM3, controlling the temperature of the reaction kettle at T4, and stirring; adding water into the reaction kettle, filtering, washing the filter cake with water, slushing the filter cake with n-heptane, filtering, washing the filter cake with n-heptane, and vacuum drying the filter cake for 5-24 hours to obtain compound 3-C.

[0050] In some embodiments, the step D comprises: adding compound 3-C into a reaction kettle under nitrogen protection, adding the potassium acetate, the BDP, the palladium catalyst, and the toluene into the reaction kettle, controlling the temperature of the reaction kettle at T5, and stirring; adding water and ethyl acetate into the reaction kettle, separating the layers, extracting the aqueous phase with ethyl acetate, combining the organic phases, and concentrating; adding n-heptane into the reaction kettle, concentrating, adding n-heptane again, filtering, washing the filter cake with n-heptane, and vacuum drying the filter cake for 5-24 hours to obtain compound 3.

[0051] In some embodiments, the inorganic base in step A is sodium carbonate, potassium carbonate, cesium carbonate, disodium hydrogen phosphate, sodium phosphate, dipotassium hydrogen phosphate, potassium phosphate, or a mixture of any two or more thereof, preferably potassium carbonate.

[0052] In some embodiments, T1 in step A is 40-80°C.

[0053] In some embodiments, T2 in step A is 50-100°C.

[0054] In some embodiments, the palladium catalyst in Step A is Pd(dppf)Cl2, Pd(dppf)Cl2CH2Cl2, Pd(PPh3)4, PdCl2(PPh3)2, PdCl2(dppe), bis(tricyclohexylphosphine)palladium, bis(tricyclohexylphosphine)palladium(II) dichloride, bis(triethylphosphine)palladium(II) chloride, bis(triphenylphosphine)palladium(II) acetate, bis(tri-tert-butylphosphine)palladium, bis[1,2-bis(diphenylphosphino)ethane]palladium, or bis[tris(o-tolyl)phosphine]palladium(II) chloride, preferably Pd(dppf)Cl2or Pd(dppf)Cl2CH2Cl2.

[0055] In some embodiments, the aprotic polar solvent in Step A is dimethyl sulfoxide (DMSO), dimethylformamide (DMF), dimethylacetamide (DMA), or dichloromethane (DCM), preferably DMF.

[0056] In some embodiments, the feeding mass ratio of the compound 9-BBN (0.5M THF solution) to the compound 3-RM1 in Step A is 20:1-8:1.

[0057] In some embodiments, the feeding mass ratio of the compound 9-BBN (0.5M THF solution) to the aprotic polar solvent in Step A is 2:1-1:1.

[0058] In some embodiments, the feeding mass ratio of the compound 3-RM1 to the inorganic base in Step A is 1:1-1:3.

[0059] In some embodiments, the feeding mass ratio of the compound 3-RM1 to the compound 3-RM2 in Step A is 1:1-2:3.

[0060] In some embodiments, the feeding mass ratio of the compound 3-RM2 to the palladium catalyst in Step A is 50:1-30:1.

[0061] In some embodiments, the mass ratio of water to MTBE added in the layering process in Step A is 4:1-2:1.

[0062] In some embodiments, the T3 in Step B is 30-60°C.

[0063] In some embodiments, the inorganic base in Step C is sodium carbonate, potassium carbonate, cesium carbonate, disodium hydrogen phosphate, sodium phosphate, dipotassium hydrogen phosphate, potassium phosphate, or a mixture of any two or more thereof, preferably potassium carbonate.

[0064] In some embodiments, the polar solvent in step C is DMSO, DMF, DMA, or DCM, preferably DMSO.

[0065] In some embodiments, the mass ratio of the compound 3-RM3 to the inorganic base in step C is 1:1-1:3.

[0066] In some embodiments, the T4 in step C is 50-100°C.

[0067] In some embodiments, the palladium catalyst in step D is Pd(dppf)Cl2, Pd(dppf)Cl2CH2Cl2, Pd(PPh3)4, PdCl2(PPh3)2, or PdCl2(dppe), preferably Pd(dppf)Cl2.

[0068] In some embodiments, the mass ratio of the compound 3-C to the potassium acetate in step D is 2:1-1:1.

[0069] In some embodiments, the mass ratio of the compound 3-C to the BDP in step D is 2:1-1:1.

[0070] In some embodiments, the mass ratio of the compound 3-C to the palladium catalyst in step D is 20:1-10:1.

[0071] In some embodiments, the mass ratio of the compound 3-C to the toluene in step D is 1:2-1:5.

[0072] In some embodiments, the T5 in step D is 50-100°C.

[0073] In some embodiments, the mass ratio of the water to ethyl acetate added in the layering process in step D is 3:1-3:2.

[0074] In a third aspect, the present application provides a method for preparing compound 4, i.e. 4-chloro-3-(2,4-dioxotetrahydropyrimidin-1(2H)-yl)benzoic acid, which is an intermediate for use as a proteolytic agent in the ubiquitin-proteasome system,

[0075] The method comprises steps a, b and c, wherein the steps a, b and c are each as shown in Reaction Scheme 2 below and as described hereinafter:

[0076] Reaction Scheme 2

[0077] wherein,

[0078] - Step a: adding compound 4-RM1 and compound 4-RM, and reacting to obtain compound 4-A;

[0079] - Step b: adding compound 4-A and glacial acetic acid, and reacting to obtain compound 4-B;

[0080] - Step c: adding compound 4-B, 1,4-dioxane and concentrated hydrochloric acid, and reacting to obtain compound 4.

[0081] In some embodiments, the steps a, b, c optionally independently comprise post-treatment selected from one or more of stirring, temperature control, concentration, distillation, extraction, filtration, washing, recrystallization, trituration, and drying.

[0082] In some embodiments, the step a is performed under an inert atmosphere, preferably under nitrogen atmosphere. In some embodiments, the step a is performed at temperature t1.

[0083] In some embodiments, the step a comprises: under nitrogen protection, adding compound 4-RM1 and compound 4-RM2 into a reaction kettle, stirring at temperature t1 for 10-48 hours, then adding a mixed solution of MTBE and n-heptane into the reaction kettle; filtering, washing the filter cake with water, and trituration of the filter cake with n-heptane; filtering, washing the filter cake with a mixed solution of MTBE and n-heptane, and vacuum drying the filter cake for 10-24 hours to obtain compound 4-A.

[0084] In some embodiments, the step b is performed under an inert atmosphere, preferably under nitrogen atmosphere. In some embodiments, the step b comprises adjusting the temperature to temperature t3 after adding urea for reaction.

[0085] In some embodiments, the step b comprises: under nitrogen protection, adding compound 4-A and glacial acetic acid into a reaction kettle; warming to t2 and adding urea; after stirring at temperature t3 for 5-24 hours, cooling to t4, and adding water into the reaction kettle; filtering, washing the filter cake with MTBE, and vacuum drying the filter cake for 10-24 hours to obtain compound 4-B.

[0086] In some embodiments, the step c is performed under an inert atmosphere, preferably under nitrogen atmosphere. In some embodiments, the step c is performed at temperature t5.

[0087] In some embodiments, the step c comprises: adding compound 4-B, 1,4-dioxane and medium concentration hydrochloric acid into a reaction kettle under nitrogen protection; after stirring at t5 for 10-48 h, the reaction solution is concentrated to dryness, acetonitrile is added, and then concentrated to dryness again; acetonitrile, MTBE and low concentration hydrochloric acid are added into the reaction kettle, and the filter cake is filtered and washed with MTBE; the filter cake, sodium bicarbonate solution and dichloromethane are added into the reaction kettle; the layers are separated, dichloromethane is added into the aqueous phase and extracted twice; the layers are separated, acetonitrile is added into the aqueous phase; medium-low concentration hydrochloric acid is added into the reaction kettle; the filter cake is filtered and washed with MTBE; the filter cake is vacuum dried to a constant weight, re-added into the reaction kettle; dimethyl sulfoxide is added into the reaction kettle; the temperature is raised to t6, and acetonitrile is added; drinking water is added into the reaction kettle; the temperature is lowered, the filter cake is filtered and washed with MTBE, and the filter cake is vacuum dried to a constant weight to obtain compound 4.

[0088] In some embodiments, the mass ratio of the compound 4-RM1 and the compound 4-RM2 in step a is 1:1-1:3.

[0089] In some embodiments, the t1 in step a is 40-80°C.

[0090] In some embodiments, the residual content of compound 4-RM1 after stirring at t1 in step a is less than 5%.

[0091] In some embodiments, the mass ratio of the compound 4-A and the glacial acetic acid in step b is 1:10-1:15.

[0092] In some embodiments, the mass ratio of the compound 4-A and the urea in step b is 2:3-1:3.

[0093] In some embodiments, the t2 in step b is 90-120°C.

[0094] In some embodiments, the t3 in step b is 60-90°C.

[0095] In some embodiments, the t4 in step b is 15-37°C.

[0096] In some embodiments, the residual content of compound 4-A after stirring at t3 in step b is less than 50%.

[0097] In some embodiments, the mass ratio of the compound 4-B and the 1,4-dioxane in step c is 1:3-1:10.

[0098] In some embodiments, the mass ratio of the compound 4-B and the medium concentration hydrochloric acid in step c is 1:4-1:10.

[0099] In some embodiments, the concentration of the medium concentration hydrochloric acid in step c is 15-23%.

[0100] In some embodiments, the concentration of the low concentration hydrochloric acid in step c is 1-5%.

[0101] In some embodiments, the concentration of the medium concentration hydrochloric acid in step c is 8-12%.

[0102] In some embodiments, the t5 in step c is 50-100°C.

[0103] In some embodiments, the residual content of compound 4-B after stirring at temperature t5 in step c is less than 10%.

[0104] In some embodiments, the mass ratio of acetonitrile, MTBE and low concentration hydrochloric acid added in the reactor in step c is 3:2:5-2:2:3.

[0105] In some embodiments, the t6 in step c is 50-100°C.

[0106] In another aspect, the present application provides a method for preparing a compound of formula (Y-2) or a salt thereof, comprising: reacting a compound of formula (Y-1) or a salt thereof with the compound 3, wherein R is C 1-2 alkyl (preferably ethyl) or Cl-substituted C 1-2 alkyl (preferably ethyl), and X 3 is Cl or Br.

[0107] In some embodiments, the reaction is carried out in a mixed solvent of an aprotic polar solvent and water in the presence of an inorganic base and a palladium catalyst under an inert atmosphere and at a temperature of about 60-90°C.

[0108] In some embodiments, the inert atmosphere is a nitrogen atmosphere.

[0109] In some embodiments, the temperature is about 60-88°C, about 65-82°C, or 68-80°C. In some preferred embodiments, the temperature is about 68-78°C.

[0110] In some embodiments, the inorganic base is sodium carbonate, potassium carbonate, cesium carbonate, disodium hydrogen phosphate, sodium phosphate, dipotassium hydrogen phosphate, potassium phosphate, or a mixture of any two or more thereof, preferably potassium phosphate.

[0111] In some embodiments, the palladium catalyst is Pd(dppf)Cl2, Pd(dppf)Cl2CH2Cl2, Pd(PPh3)4, PdCl2(PPh3)2, PdCl2(dppe), bis(tricyclohexylphosphine)palladium, bis(tricyclohexylphosphine)palladium(II) dichloride, bis(triethylphosphine)palladium(II) chloride, bis(triphenylphosphine)palladium(II) acetate, bis(tri-tert-butylphosphine)palladium, bis[l,2-bis(diphenylphosphino)ethane]palladium, bis[tris(o-tolyl)phosphine]palladium(II) chloride. In some preferred embodiments, the second palladium catalyst is Pd(PPh3)4.

[0112] In some embodiments, the aprotic polar solvent is 1,4-dioxane, THF, 2- methyltetrahydrofuran (2-MeTHF), or acetonitrile (ACN), preferably 1,4-dioxane or 2-MeTHF.

[0113] In some preferred embodiments, the method comprises:

[0114] In some preferred embodiments, the method comprises:

[0115] In another aspect, the present application provides the use of tert-butyl 4-((l-(5-(4,4,5,5-tetramethyl-l,3,2-dioxaborolan-2-yl)pyridin-2-yl)piperidin-4- yl)methyl)piperidine-l-carboxylate as an intermediate in the preparation of a targeted protein degrader for the ubiquitin-proteasome system, preferably as a targeted protein degrader intermediate. In some embodiments, the targeted protein degrader is compound C195 and / or C196:

[0116] In another aspect, the present application provides the use of tert-butyl 4-((l-(5-(4,4,5,5-tetramethyl-l,3,2-dioxaborolan-2-yl)pyridin-2-yl)piperidin-4- yl)methyl)piperidine-l-carboxylate as an intermediate in the preparation of a medicament for preventing or treating a CRBN-related disease or disorder. In some embodiments, the medicament is compound C195 and / or C196, as described above.

[0117] In another aspect, the present application provides the use of compound 3 as an intermediate in the preparation of compound Y-2:

[0118] wherein R is a C 1-2 alkyl (preferably ethyl) or Cl substituted C 1-2alkyl (preferably ethyl).

[0119] In another aspect, the present application provides use of the compound 3 for providing a linker between a target protein binding ligand and an E3 ubiquitin ligase ligand in a protein degradation targeting chimera (PROTAC) compound, wherein the linker comprises partially, or consists of.

[0120] In another aspect, the present application provides use of the compound 3 as an intermediate in the preparation of the above-mentioned compounds C195 or C196.

[0121] In another aspect, the present application provides use of tert-butyl 4-((1-(5-(4,4,5,5-tetramethyl-1,3,2-dioxaboran-2-yl)pyridin-2-yl)piperidin-4-yl)methyl)piperidine-1-carboxylate as an intermediate in the preparation of a medicament for preventing or treating a HPK1 related disease or disorder. In some embodiments, the medicament is compound C195 and / or C196, as described above.

[0122] As an example, but not limited thereto, tert-butyl 4-((1-(5-(4,4,5,5-tetramethyl-1,3,2-dioxaboran-2-yl)pyridin-2-yl)piperidin-4-yl)methyl)piperidine-1-carboxylate can be used in the synthetic route of C195 and C196 in International Patent Application PCT / CN2023 / 139101 to replace compound C195-f and / or C196-f.

[0123] As an example, but not limited thereto, 4-chloro-3-(2,4-dioxotetrahydropyrimidin-1(2H)-yl)benzoic acid can be used in the synthetic route of C195 and C196 in International Patent Application PCT / CN2023 / 139101 (i.e., compound 291j). Advantages

[0124] The preparation method of the present application has low raw material cost, good process stability, controllable product quality, and is suitable for industrial production of kilograms or more. The preparation process uses continuous feeding, and does not need separate purification after each reaction, which is simple to operate and can reduce product loss and improve yield. BRIEF DESCRIPTION OF DRAWINGS

[0125] Figure 1: HPLC spectrum of compound 3 prepared in Example 4.

[0126] Figure 2: HPLC spectrum of compound 4 prepared in Example 7. DETAILED DESCRIPTION

[0127] The application will be further described in conjunction with specific examples. The following examples are only used to understand the method and core idea of the application, and are not intended to limit the scope of the application. Any possible changes or replacements made by those skilled in the art without departing from the concept of the application shall fall within the protection scope of the application.

[0128] The experimental methods not specified in the examples are usually conventional conditions, or according to the conditions suggested by the raw material or commercial manufacturer; the reagents not specified by the source are usually conventional reagents available through commercial channels or can be prepared by conventional methods from known reagents.

[0129] Examples

[0130] Example 1: Preparation of compound 3-A (step A)

[0131] Under nitrogen protection, 547.8 kg of compound 9-BBN (0.5 M THF solution) was added to the reaction kettle; 49.8 kg of compound 3-RM1 was added to the reaction kettle; the temperature of the reaction kettle was controlled at 62°C, and stirred for 2 hours, and then THF was removed by reduced pressure concentration; 472.1 kg of DMF was added to the reaction kettle; 49.8 kg of drinking water was added to the reaction kettle; 104.6 kg of potassium carbonate was added to the reaction kettle; 53.8 kg of compound 3-RM2 was added to the reaction kettle; 1.49 kg of Pd(dppf)Cl2 was added to the reaction kettle; the temperature of the reaction kettle was controlled at 70°C, and stirred for 16 hours under nitrogen atmosphere; 747 kg of drinking water was added to the reaction kettle; 249 kg of MTBE was added to the reaction kettle; the layers were separated, and the aqueous phase was extracted with 249 kg of MTBE; the organic phases were combined and washed with 199.2 kg of drinking water; the organic phases were combined and concentrated without fractionation; 149.4 kg of glacial acetic acid was added to the reaction kettle, and the resulting solution containing compound 3-A was directly used for the next step of production.

[0132] Example 2: Preparation of compound 3-B (step B)

[0133] Under nitrogen protection, 93.5 kg of compound 3-A in acetic acid solution (containing 23.3 kg of compound 3-A) was added to the reaction kettle; 3.15 kg of palladium on carbon was added to the reaction kettle; hydrogen was introduced into the reaction kettle at 1.5 MPa, and the temperature of the reaction kettle was controlled at 48°C, and stirred for 40 hours; after depressurization, the temperature was lowered to room temperature, and filtered; the filter cake was washed with 69.9 kg of glacial acetic acid, and the solution containing compound 3-B was directly used for the next step of production.

[0134] Example 3: Preparation of 3-C (step C)

[0135] Under nitrogen protection, 176 kg of compound 3-B acetic acid solution (containing 23.8 kg of compound 3-B) was concentrated to dryness, and 238 kg of acetonitrile was added twice for distillation; 209.4 kg of DMSO was added; 52.4 kg of potassium carbonate was added; 16.7 kg of compound 3-RM3 was added; the temperature of the reaction kettle was controlled at 80°C, and stirring was carried out for 8 hours; 511.7 kg of drinking water was added to the reaction kettle; filtration was carried out, and the filter cake was washed with 119 kg of drinking water; the filter cake was slurried with 114.2 kg of n-heptane; filtration was carried out, and the filter cake was washed with 30.9 kg of n-heptane; the filter cake was vacuum dried for 12 hours to obtain compound 3-C, and the yield was 20.06 kg. The yield was 54.3%.

[0136] Example 4: Preparation of compound 3 (step D)

[0137] Under nitrogen protection, 20 kg of compound 3-C was added to the reaction kettle; 13.4 kg of potassium acetate was added to the reaction kettle;

[0138] 14.5 kg of BDP was added to the reaction kettle; 1.6 kg of Pd(dppf)Cl2 was added to the reaction kettle; 80 kg of toluene was added to the reaction kettle; the temperature of the reaction kettle was controlled at 80°C, and stirring was carried out for 8 hours; 200 kg of drinking water was added to the reaction kettle; 100 kg of ethyl acetate was added to the reaction kettle; the layers were separated, and the aqueous phase was extracted with 80 kg of ethyl acetate; the organic phases were combined and concentrated to 100 L; 100 kg of n-heptane was added to the reaction kettle; the concentration was carried out to 100 L, 100 kg of n-heptane was added to the reaction kettle; filtration was carried out, and the filter cake was washed with 30 kg of n-heptane; the filter cake was vacuum dried for 10 hours to obtain compound 3, which was a brown solid, and the yield was 16.12 kg. The yield was 72.93%.

[0139] 1 H NMR (400 MHz, CDCl3) δ 8.53 (s, 1H), 7.78 (d, J = 8.5 Hz, 1H), 6.59 (d, J = 8.7 Hz, 1H), 4.37 (d, J = 13.1 Hz, 2H), 4.08 (s, 2H), 2.83 (td, J = 12.9, 2.0 Hz, 2H), 2.68 (t, J = 11.9 Hz, 2H), 1.73 (d, J = 12.6 Hz, 2H), 1.63 (d, J = 6.6 Hz, 3H), 1.52 (s, 1H), 1.46 (s, 9H), 1.31 (s, 12H), 1.22 - 1.14 (m, 4H), 1.07 (ddd, J = 16.3, 12.6, 4.4 Hz, 2H).

[0140] Example 5: Preparation of compound 4-A (step a)

[0141] Under the protection of nitrogen, 19.5 kg of compound 4-RM1 was added into the reaction kettle; 30.2 kg of compound 4-RM2 was added into the reaction kettle; temperature was controlled at 60 ℃, and the reaction was stirred for 26 h; sampling was sent to HPLC for control, and the residual compound 4-RM1 was ≤4.0%; 55.4 kg of MTBE and n-heptane mixed solution was added into the reaction kettle; filtration was carried out, and the filter cake was washed with 119 kg of drinking water; the filter cake was slurried with 114.2 kg of n-heptane; filtration was carried out, and the filter cake was washed with 27.7 kg of MTBE and n-heptane mixed solution; the filter cake was vacuum dried for 12 h to obtain 23.35 kg of compound 4-A, and the yield was 86.26%.

[0142] Example 6: Preparation of compound 4-B (step b)

[0143] Under the protection of nitrogen, 23.3 kg of compound 4-A was added into the reaction kettle; 244.7 kg of glacial acetic acid was added into the reaction kettle; the temperature was increased to 110 ℃, and 55.9 kg of urea was added; the temperature of the reaction kettle was controlled at 80 ℃, and the reaction was stirred for 8 h; sampling was sent to HPLC for control, and the residual compound 4-A was ≤40%; the temperature was decreased to 25 ℃, 233 kg of drinking water was added into the reaction kettle; filtration was carried out, and the filter cake was washed with 34.5 kg of MTBE; the filter cake was vacuum dried for 12 h to obtain 15.51 kg of compound 4-B, and the yield was 61.07%.

[0144] Example 7: Preparation of compound 4 (step c)

[0145] Into a reaction kettle, add 15.5 kg of compound 4-B; into the reaction kettle, add 77.5 kg of 1,4-dioxane; into the reaction kettle, add 93 kg of 18% hydrochloric acid; control the temperature of the reaction kettle at 80 °C, stir for 24 hours; take samples for HPLC control, the residual compound 4-B is ≤7%; concentrate the reaction liquid to dryness, add 61.2 kg of acetonitrile; concentrate to dryness again; into the reaction kettle, add 24.5 kg of acetonitrile; into the reaction kettle, add 22.9 kg of MTBE; into the reaction kettle, add 31 kg of 3% hydrochloric acid; filter, wash the filter cake with 22.9 kg of MTBE; into the reaction kettle, add the filter cake, add 310 kg of 5% sodium bicarbonate solution into the reaction kettle, add 204 kg of dichloromethane; separate the layers, add 102 kg of dichloromethane to the aqueous phase and extract twice; separate the layers, add 61.2 kg of acetonitrile to the aqueous phase; into the reaction kettle, add 87.4 kg of 9% hydrochloric acid; filter, wash the filter cake with 22.9 kg of MTBE; vacuum dry the filter cake to constant weight, re-put into the reaction kettle; into the reaction kettle, add 27.9 kg of dimethyl sulfoxide; warm up to 85 °C, add 80.3 kg of acetonitrile; into the reaction kettle, add 25.4 kg of drinking water; cool down to 0 °C, filter, wash the filter cake with 18.8 kg of MTBE; vacuum dry the filter cake to constant weight to obtain compound 4, yield 15.51 kg. Yield 61.07%.

[0146] 1 H NMR (400 MHz, DMSO) δ 13.36 (bs, 1H), 10.53 (s, 1H), 8.05 (d, J = 2.0 Hz, 1H), 7.91 (dd, J = 8.4, 2.1 Hz, 1H), 7.71 (d, J = 8.4 Hz, 1H), 3.79 (ddd, J = 13.8, 8.5, 5.7 Hz, 1H), 3.62 (dt, J = 12.2, 6.2 Hz, 1H), 2.87 - 2.65 (m, 2H).

[0147] Example 8: Synthesis of tert-butyl 4-((l-(5-(5-(benzenesulfonyl)-7-(l-(2,2,2- trifluoroethyl)-lH-pyrazol-4-yl)-5H-pyrrolo[2,3-b]pyrazin-2-yl)pyridin-2-yl)piperidin-4- yl)methyl)piperidine-l-carboxylate (C196g)

[0148] This example provides a compound of Formula (Y-2) wherein R is -CH2-CF3 (i.e., synthesis of C196g).

[0149] Compound C196g was prepared according to the procedure including the operations described below using the reaction conditions listed in the table below:

[0150] 1. Add C196e (compound of formula (Y-1) wherein R is -CH2-CF3 and X is Br), compound 3, inorganic base, aprotic polar solvent and purified water to a reaction vessel and stir, sparge with nitrogen three times. 3 1 Stir, sparge with nitrogen three times.

[0151] 2. Add Pd(PPh3)4 to a reaction vessel and stir, sparge with nitrogen three times.

[0152] 3. Heat under nitrogen and react for 16-20 hours.

[0153] 4. Adjust the temperature in the reaction vessel to 20-30°C, add purified water and stir, then filter the reaction mixture and collect the filtrate.

[0154] 5. Add the aprotic polar solvent used in procedure 1 to a reaction vessel, wash the lines and filter cake, and combine with the filtrate from procedure 4.

[0155] 6. Allow the combined filtrate to separate into layers, separate, retain organic phase 1, and discard aqueous phase 1.

[0156] 7. Wash organic phase 1 with 5% sodium chloride solution (5.00 w / w), separate, retain organic phase 2, and discard aqueous phase 2.

[0157] 8. Repeat procedure 7 to obtain organic phase 3.

[0158] 9. Concentrate organic phase 3 under reduced pressure.

[0159] 10. Crystallization: adjust the internal temperature to 45-55°C, add MTBE dropwise and stir for 1-3 hours, then cool to 0-10°C and stir at that temperature for 4-6 hours.

[0160] 11. Centrifuge the material, then wash the lines and filter cake.

[0161] 12. Slurry: add the filter cake to a reaction vessel, then add 2-MeTHF and stir at a temperature of 45-55°C for 1-3 hours, then add MTBE dropwise and continue stirring at 45-55°C for 1-3 hours; then cool to 0-10°C and stir at that temperature for 4-6 hours.

[0162] 13. Centrifuge the material, then wash the lines and filter cake.

[0163] 14. Vacuum dry the filter cake to obtain the target product C196g.

[0164] 1H NMR (400 MHz, CDC13) δ 8.89 (d, J = 2.4 Hz, 1H), 8.75 (s, 1H), 8.39 (s, 1H), 8.23 - 8.16 (m, 2H), 8.16 - 8.07 (m, 3H), 7.61 (t, J = 7.4 Hz, 1H), 7.52 (t, J = 7.7 Hz, 2H), 6.77 (d, J = 9.0 Hz, 1H), 4.80 (q, J = 8.3 Hz, 2H), 4.41 (d, J = 13.2 Hz, 2H), 4.09 (s, 2H), 2.92 (dd, J = 12.4, 10.7 Hz, 2H), 2.70 (t, J = 11.9 Hz, 2H), 1.79 (d, J = 12.5 Hz, 2H), 1.73 - 1.59 (m, 2H), 1.58 - 1.39 (m, 10H), 1.34 - 1.15 (m, 5H), 1.09 (ddd, J = 16.3, 12.6, 4.3 Hz, 2H).

[0165] Example 9: Synthesis of 1-(2-chloro-5-(4-((1-(5-(7-(1-(2,2,2-trifluoroethyl)-1H- pyrazol-4-yl)-5H-pyrrolo[2,3-b]pyrazin-2-yl)pyridin-2-yl)piperidin-4-yl)methyl)piperidine-1- carbonyl)phenyl)dihydropyrimidine-2,4(1H,3H)-dione (C196)

[0166] In this example, C196 was synthesized using compound C196 i and compound 4:

[0167] Compound C196 was prepared according to the procedure including the operations described below using the reaction conditions listed in the table below:

[0168] 1. Into a reaction kettle was added C196 i, an aprotic polar solvent, an organic base, and compound 4, followed by a condensing agent, and reacted at 20-30 °C for 12-18 hours.

[0169] 2. Into the reaction kettle was added dichloromethane and methanol in sequence, followed by 2% aqueous sodium bicarbonate solution to terminate the reaction, stirred at 20-30 °C for 20-40 minutes, and then left to stand at temperature to separate into layers, the organic phase was taken, and the aqueous phase was discarded.

[0170] 3. The organic phase was subjected to post-treatment to obtain the final product C196.

[0171] 1H NMR (500 MHz, DMSO-d6) δ 12.05 (s, 1H), 10.52 (s, 1H), 9.00 (d, J = 2.4 Hz, 1H), 8.81 (s, 1H), 8.55 (s, 1H), 8.33 (dd, J = 9.0, 2.5 Hz, 1H), 8.18 (d, J = 2.5 Hz, 2H), 7.64 (d, J = 8.2 Hz, 1H), 7.56 (d, J = 2.0 Hz, 1H), 7.39 (dd, J = 8.2, 1.9 Hz, 1H), 6.96 (d, J = 9.1 Hz, 1H), 5.26 (q, J = 9.1 Hz, 2H), 4.43 (dd, J = 24.4, 11.2 Hz, 3H), 3.80 - 3.73 (m, 1H), 3.66 - 3.54 (m, 2H), 3.12 - 3.01 (m, 1H), 2.89 (s, 2H), 2.75 (q, J = 7.4, 6.6 Hz, 2H), 1.80 - 1.60 (m, 6H), 1.26 - 1.04 (m, 7H).

[0172] In addition to those described herein, various modifications and alterations of the present application are also intended to fall within the scope of the appended claims. Each reference cited in this application, including all patents, patent applications, journal articles, books and any other publications, are hereby incorporated by reference in their entireties.

Claims

1. A process for the preparation of compound 3, Scheme 1A characterized in that said process comprising the following steps: - Step A comprising obtaining compound 3-A from compound 3-RM1 and compound 3-RM2; - Step B comprising subjecting compound 3-A to a reduction reaction to obtain compound 3-B; - Step C comprising reacting compound 3-B and compound 3-RM3 to obtain compound 3-C; - Step D comprising reacting compound 3-C with bis(pinacolato)diboron (BDP) to obtain compound 3.

2. The process according to claim 1, wherein said Step A comprises subjecting compound 3-RM1, a THF solution of 9-borabicyclo[3,3,1]-nonane (9-BBN) and compound 3-RM2 to a reaction catalyzed by a palladium catalyst in the presence of an aprotic polar solvent, water and an inorganic base to obtain compound 3-A; Preferably, said Step A is carried out under an inert atmosphere, preferably under a nitrogen atmosphere; More preferably, said Step A comprises: (1) mixing said THF solution of 9-BBN and compound 3-RM1 under said inert atmosphere, followed by removing THF at a temperature T1; and (2) subjecting the mixture obtained from step (1) and compound 3-RM2 to a reaction catalyzed by said palladium catalyst in the presence of said aprotic polar solvent, said water and said inorganic base at a temperature T2 to obtain compound 3-A; and / or Further more preferably, said Step A comprises: (1) mixing a THF solution of compound 9-BBN and compound 3-RM1 under nitrogen protection, followed by removing THF by concentration (e.g. under reduced pressure) at a temperature T1; and (2) subjecting the mixture obtained from step (1) and said aprotic polar solvent, said water, said inorganic base, compound 3-RM2 and said palladium catalyst to a reaction at a temperature T2 under a nitrogen atmosphere to obtain compound 3-A.

3. The process according to claim 1 or 2, wherein said Step B comprises subjecting compound 3-A to a reduction reaction catalyzed by palladium on carbon in a hydrogen atmosphere to obtain compound 3-B; Preferably, said Step B comprises subjecting an acetic acid solution of compound 3-A to a reduction reaction catalyzed by palladium on carbon in a hydrogen atmosphere to obtain compound 3-B; More preferably, said reduction reaction is carried out at a temperature T3; and / or Further more preferably, said Step B comprises subjecting an acetic acid solution of compound 3-A to a reduction reaction catalyzed by palladium on carbon in a hydrogen atmosphere at a temperature T3 to obtain compound 3-B.

4. The process according to any one of claims 1-3, wherein said Step C comprises reacting compound 3-B with compound 3-RM3 in the presence of a polar solvent and an inorganic base to obtain compound 3-C; Preferably, said Step C is carried out under an inert atmosphere, preferably under a nitrogen atmosphere; and / or the reaction in said Step C is carried out at a temperature T4; More preferably, said step C comprises reacting compound 3-B in the presence of a polar solvent and an inorganic base and compound 3-RM3 under a nitrogen atmosphere at a temperature T4, to give compound 3-C.

5. The method according to any one of claims 1-4, wherein said step D comprises reacting compound 3-C in the presence of a palladium catalyst and a base metal acetate in toluene with BDP, to give compound 3. Preferably, said step D is carried out under an inert atmosphere, preferably a nitrogen atmosphere; and / or, the base metal acetate in said step D is sodium acetate or potassium acetate, preferably potassium acetate; and / or, the reaction in said step D is carried out at a temperature T5. More preferably, said step D comprises reacting compound 3-C in the presence of a palladium catalyst and potassium acetate in toluene with BDP under a nitrogen atmosphere at a temperature T5, to give compound 3.

6. A process for the preparation of compound 3, characterized in that The method comprises the following steps: - step A comprising adding compound 3-RM1 to a THF solution of compound 9-BBN, adding compound 3-RM2, a polar solvent and an inorganic base and catalyzing the reaction with a palladium catalyst, to give compound 3-A; - step B comprising adding palladium on carbon to a solution of compound 3-A, to give compound 3-B; - step C comprising adding a polar solvent, an inorganic base and compound 3-RM3 to a solution of compound 3-B, to give compound 3-C; - step D comprising adding compound 3-C, potassium acetate, BDP, a palladium catalyst, toluene, to give compound 3.

7. The method according to any one of claims 1-6, wherein said steps A, B, C, D optionally independently comprise a work-up selected from one or more of stirring, temperature control, concentration, distillation, extraction, filtration, washing, recrystallization, trituration, drying.

8. The method of any one of claims 1-7, wherein; the mass ratio of the compound 3-RM1 to the compound 3-RM2 in step A is 1:1 to 2:3; and / or, the inorganic base in step A is sodium carbonate, potassium carbonate, cesium carbonate, disodium hydrogen phosphate, sodium phosphate, dipotassium hydrogen phosphate, potassium phosphate, or a mixture of any two or more thereof, preferably potassium carbonate; and / or, the palladium catalyst in step A is Pd(dppf)Cl2, Pd(dppf)Cl2-CH2Cl2, Pd(PPh3)4, PdCl2(PPh3)2, PdCl2(dppe), bis(tricyclohexylphosphine)palladium, bis(tricyclohexylphosphine)palladium(II) chloride, bis(triethylphosphine)palladium(II) chloride, bis(triphenylphosphine)palladium(II) acetate, bis(tri-tert-butylphosphine)palladium, bis[l,2-bis(diphenylphosphino)ethane]palladium, bis[tris(o-tolyl)phosphine]palladium(II) chloride, preferably Pd(dppf)Cl2or Pd(dppf)Cl2-CH2Cl2; and / or, the polar solvent in step A is DMSO, DMF, DMA, DCM, preferably DMF; and / or, the mass ratio of compound 9-BBN (0.5M THF solution) to compound 3-RM1 in step A is 20:1 to 8:1; and / or, the mass ratio of compound 3-RM2 to the palladium catalyst in step A is 50:1 to 30:1; and / or, the reaction temperature in step B is 30-60°C.

9. The method of any one of claims 1-8, wherein: the inorganic base in step C is sodium carbonate, potassium carbonate, cesium carbonate, disodium hydrogen phosphate, sodium phosphate, dipotassium hydrogen phosphate, potassium phosphate, or a mixture of any two or more thereof, preferably potassium carbonate; and / or, the polar solvent in step C is DMSO, DMF, DMA, DCM, preferably DMSO; and / or, the mass ratio of compound 3-RM3 to the inorganic base in step C is 1:1 to 1:3; and / or, the mass ratio of compound 3-C to the potassium acetate in step D is 2:1 to 1:1; and / or, the mass ratio of compound 3-C to the BDP in step D is 2:1 to 1:1; and / or, the mass ratio of compound 3-C to the palladium catalyst in step D is 20:1 to 10:

1.

10. A process for the preparation of compound 4, characterized in that The method comprises the following steps: - step a: adding compound 4-RM1 and compound 4-RM, and reacting to obtain compound 4-A; - step b: adding compound 4-A and glacial acetic acid, heating to t2, and adding urea and stirring, and reacting to obtain compound 4-B; - step c: adding compound 4-B, 1,4-dioxane, and concentrated hydrochloric acid, and reacting to obtain compound 4.

11. The method of claim 10, wherein the steps a, b, c optionally independently comprise post-treatment selected from one or more of stirring, temperature control, concentration, distillation, extraction, filtration, washing, recrystallization, trituration, and drying.

12. The preparation method according to claim 10 or 11, wherein: said step a is carried out under an inert atmosphere, preferably under a nitrogen atmosphere; and / or, said step a is carried out at a temperature t1; and / or, said step b is carried out under an inert atmosphere, preferably under a nitrogen atmosphere; and / or, said step b comprises adjusting the temperature to a temperature t3 after adding urea to carry out the reaction; and / or, said step c is carried out under an inert atmosphere, preferably under a nitrogen atmosphere; and / or, said step c is carried out at a temperature t5.

13. The method of any one of claims 10-12, wherein: the feeding mass ratio of said compound 4-RM1 and said compound 4-RM2 in step a is 1:1-1:3; and / or, the reaction temperature t1 of step a is 40-80°C; and / or, the feeding mass ratio of said compound 4-A and said glacial acetic acid in step b is 1:10-1:15; and / or, the feeding mass ratio of said compound 4-A and said urea in step b is 2:3-1:3; and / or, said t2 in step b is 90-120°C; and / or, the feeding mass ratio of said compound 4-B and said 1,4-dioxane in step c is 1:3-1:

10.

14. Use of compound 3 obtained according to the process of any one of claims 1-9, for the manufacture of a target protein degrader of the ubiquitin-proteasome system, preferably as an intermediate of a target protein degrader, wherein the target protein degrader is preferably compound C195 and / or C196: ###0002### C195 C196 ​ 15. Use of compound 3 obtained according to the process of any one of claims 1-9 as an intermediate in the preparation of a medicament for the prevention or treatment of a CRBN-related disease or disorder, wherein the medicament is preferably compound C195 and / or C196:

16. A method of using compound 3 as claimed in claim 1 for the preparation of a compound of formula (Y-2) or a salt thereof: The method comprises reacting a compound of formula (Y-1) or a salt thereof with the compound 3, wherein: R is F-substituted C 1-2 alkyl or Cl-substituted C 1-2 alkyl, and X 3 is Cl or Br.

17. Use of the compound 3 according to claim 1 as an intermediate for the preparation of compound Y-2: wherein R is F substituted C 1-2 alkyl or Cl substituted C 1-2 alkyl.

18. Use of Compound 3 as claimed in claim 1 for providing a linker between a target protein binding ligand and an E3 ubiquitin ligase ligand in a protein degradation targeted chimera (PROTAC) compound, wherein the linker comprises Part, or consists of:

19. The compound of claim 1, 3:

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