Method for preparing drug linker complexes and intermediates thereof

Abstract

The present invention provides a method for preparing a drug linker complex. The present invention further provides a method for preparing an intermediate or a salt thereof to be used and the use of the intermediate or a salt thereof. The raw materials according to the preparation method described in the present invention are easy to obtain, simple to operate, have high product purity, and are suitable for large-scale synthesis.

Description

[Technical Field]

[0001] This application claims priority to Chinese patent application 2022106005234, filed on 30 May 2022, and Chinese patent application 2022110295935, filed on 25 August 2022. The full text of the aforementioned Chinese patent applications is incorporated herein by reference. This application belongs to the field of medicinal chemistry, and more specifically, it relates to a method for preparing drug linker complexes or salts thereof, and related intermediates or salts thereof. [Background technology]

[0002] Antibody-drug conjugates (ADCs) are complexes of antibodies and small molecule drugs, combining the tumor-targeting activity of antibodies with the activity of bioactive molecules to form a biological missile, offering highly promising therapeutic effects and safety advantages. The antibody induces the binding of the ADC to target cells / tissues, and then the small molecule drug is released into the cells / tissues by the action of specific enzymes, treating the disease. Among these, the drug linker complex (including the cytotoxic payload and linker) plays a crucial role in the preparation of ADCs. Therefore, the development of a simple, efficient, low-cost method for synthesizing drug linker complexes suitable for large-scale synthesis is of great significance for the development and application of ADC drugs.

[0003] Ds8201a is an already commercially available ADC molecule, and its toxin linker has a relatively specific azaacetal structure.

[0004] [ka]

[0005] ) contains and has a good therapeutic effect against breast cancer, which is highly expressed in Her2. However, there are limited methods for synthesizing the azaacetal structure contained in the ADC molecule. One method is to oxidize and rearrange the carboxylic acid with Pb(OAc)4 to obtain an acetate ester structure, and then obtain the target molecule with an acid catalyst. The Pb(OAc)4 used in this method has strict substrate restrictions and cannot contain an oxidizable group (e.g., amino group, substituted amino group) in the molecule; otherwise, the reaction yield is extremely low. Another method is to oxidize and rearrange with Pb(OAc)4 to obtain an acetate ester structure, react it with a halogenating agent (e.g., TMSCl, TMSBr) to obtain a halide, and then undergo a nucleophilic substitution reaction with the hydroxyl group of the substrate under basic conditions. This method uses Pb(OAc)4 and a base (e.g., potassium tert-butoxide) in the nucleophilic substitution reaction, but is not suitable for base-unstable substrates such as camptothecin compounds. At the same time, all of the above methods use Pb(OAc)4, and since Pb remains in the system, it causes poisoning of the corresponding metal catalyst when removing the amino protecting group by metal catalytic hydrogenation in a later reaction, significantly affecting the reaction yield. Therefore, there is a strong need to develop a new method for synthesizing azaacetals to overcome problems such as high substrate restrictions and low reaction yields, and to meet the demand for large-scale production.

[0006] WO2022170971 discloses an ADC molecule containing an azaacetal structure with good antitumor activity. The synthetic route of the drug linker conjugate used to prepare the ADC molecule is shown below:

[0007] [ka]

[0008] This pathway uses A1.9 as a starting material and yields the target compound through a three-step reaction. However, it has several drawbacks: 1) A1.9 is a cytotoxic compound and a highly active molecule, requiring the use of an isolator in the three-step reaction during large-scale production, making it difficult to operate; 2) B1.14-A is one of the key intermediates in this pathway and requires purification by column chromatography, resulting in high solvent usage and making large-scale production difficult; 3) B1.14 is the second key intermediate in this pathway, has relatively poor chemical stability, polymerizes rapidly, and makes quality control difficult during large-scale production; and 4) the overall yield of this pathway is <5% (calculated based on A1.9), resulting in high costs.

[0009] In summary, the above-mentioned pathway is not suitable for scaling up the process. How to reduce the reaction steps involving highly active molecules, avoid the appearance of unstable intermediates, simplify the purification method, and improve the yield directly affects whether scaling up the process can proceed smoothly. Therefore, there is an urgent need to develop new synthetic pathways that can meet the demand for scaling up production. [Overview of the project]

[0010] This application provides a method for preparing a compound of formula I as a drug linker complex, as well as a method for preparing an intermediate or a salt thereof used therein, and the use of the intermediate or a salt thereof. The preparation method described herein has broad substrate applicability, is simpler to operate, and is suitable for large-scale production.

[0011] In one embodiment, the present application provides a method for preparing a compound of formula I or a salt thereof.

[0012] [ka]

[0013] During the ceremony, D is a fragment of a bioactive molecule, preferably a fragment of a bioactive molecule of formula IA camptothecin.

[0014] [ka]

[0015] During the ceremony, R1 and R2 are independently selected from H, halogen, -OH, optionally substituted C1-6 alkyl groups, and optionally substituted C1-6 alkoxy groups, or, R1 and R2, together with the carbon atoms linked to them, form a 5-7 membered carbon ring or a 5-7 membered heterocycle, and the heterocycle contains one or more of O, S, N, a carbonyl group, a sulfoxide group, or a sulfone group, or any combination thereof. R3 is selected from H, halogens, -OH, -NH2, optionally substituted C1-6 alkyl groups, and optionally substituted C1-6 alkoxy groups, or R3 and X, together with the carbon atoms linked to them, form a 5-7 membered carbon ring or a 5-7 membered heterocycle, and the heterocycle contains one or more of O, S, N, a carbonyl group, a sulfoxide group, or a sulfone group, or any combination thereof, or R3 and R2, together with the carbon atoms linked to them, form a 5-7 membered carbon ring or a 5-7 membered heterocycle, and the heterocycle contains one or more of O, S, N, a carbonyl group, a sulfoxide group, or a sulfone group, or any combination thereof. W either does not exist or exists, and if W exists, W is

[0016] [ka]

[0017] Selected from, the 1st position is linked to X, and the 2nd position is linked to the oxygen atom, X is directly bonded, or optionally substituted -O-(CH2) n3 -, -N(R4)-(CH2) n3 -, -S-(CH2) n3 -, carbonyl-(CH2) n3 -SO2-(CH2)n3 -,

[0018] [Chemical formula]

[0019] -(CH2) n1 -, a C3-6 cycloalkyl group, a C6-10 aryl group, a 5-10 member heteroaryl group, and a 4-10 member heterocyclic group, wherein the 1-position is linked to the parent ring, the 2-position is linked to W or an oxygen atom, and the substituent is selected from one or more C1-4 alkyl groups, C3-6 cycloalkyl groups, or a plurality of C1-4 alkyl groups together with the carbon atom to which they are simultaneously linked form a C3-6 cycloalkyl group, Each M is independently selected from a direct bond and -CR 5a R 5b -, R4, R5, R 5a , R 5b , R6, R7 are each independently selected from H, an optionally substituted C1-4 alkyl group, an optionally substituted C1-4 alkoxy group, and an optionally substituted C3-6 cycloalkyl group, n, n’, n1, n2, n3 are each independently selected from any integer between 0 and 6, More preferably, Formula I-A is

[0020] [Chemical formula] [[ID=​​​​​​​​​​​​​​​​​​​​​​​​​Lg is a leaving group that reacts with antibodies, and Lg can be a halogen, a sulfone group, or a tertiary amine base (Me3N). + , Et3N + ), selected from diazonium bases, -OMs, MeSO2-, CF3SO3-, preferably Lg is selected from F, Cl, MeSO2-, more preferably Lg is MeSO2-, L 1 teeth

[0024] [ka]

[0025] If that is the case, Lg does not exist. L 2 teeth

[0026] [ka]

[0027] Selected from, the winner is L 1 L is linked to 2nd place. 3 Connect to, n4 is selected from any integer between 0 and 10. Y is selected from -CH2- and -OCH2CH2-. Z is CR m R n , NR m Selected from, R m , R n Each of these is independently selected from H, deuterium, C1-4 alkyl groups, C2-4 alkenyl groups, C2-4 alkynyl groups, C3-6 cycloalkyl groups, and 3-6 membered heterocyclic groups. Alternatively, R m and R n These, together with the carbon atoms linked to them, form a 3-6 membered carbon ring or a 3-6 membered heterocycle. L 3 The peptide is selected from short peptides consisting of 2 to 10 amino acid residues, and these amino acid residues may be natural amino acid residues, unnatural amino acid residues, or AA.1 Selected from the amino acid residues shown or their stereoisomers, AA 1 The structure of the amino acid residue shown is as follows:

[0028] [ka]

[0029] During the ceremony, R a , R b H and

[0030] [ka]

[0031] Selected from and R a , R b It is not H at the same time, Alternatively, R a and R b These, together with the carbon atoms linked to them, form a 4-10 membered heterocycle, and the above 4-10 membered heterocycle can optionally have one or more R 0 Replaced by, r, r 1 Each of these is independently selected from any integer between 0 and 20. R m1 , R n1 Each of these is independently selected from H, C1-6 alkyl groups, and C3-6 cycloalkyl groups. Alternatively, R m1 and R n1 These, together with the nitrogen atoms linked to them, form a 4- to 10-membered heterocycle, and the above 4- to 10-membered heterocycle can optionally have one or more R atoms. 0’ Replaced by, R 0 , R 0’ These are, independently, C1-6 alkyl groups, C3-6 cycloalkyl groups, and -NR groups. m2 R n2and optionally selected from 4-10 membered heterocyclic groups substituted with C1-6 alkyl groups, R m2 , R n2 Each of these is independently selected from H and C1-6 alkyl groups.

[0032] The above preparation method is: The process includes the step of reacting a compound of formula I-1 or a salt thereof with a compound of formula X-3 or a salt thereof to obtain a compound of formula I or a salt thereof.

[0033] [ka]

[0034] In the formula, R8 is hydrogen, C1-30 alkyl group, C3-7 cycloalkyl group, 3-20 member heterocyclic group, 5-10 member heteroaryl group, C6-10 aryl group, C1-6 alkyl-C3-6 cycloalkyl group, C1-6 alkyl-4-6 member heterocyclic group, C1-6 alkyl-5-10 member heteroaryl group, C1-6 alkyl-C6-10 aryl group,

[0035] [ka]

[0036] Selected from the above alkyl groups, cycloalkyl groups, heterocyclic groups, heteroaryl groups, and aryl groups, one or more R groups are optionally selected. x Replaced by, R x This includes hydrogen, deuterium, halogens, hydroxyl groups, C1-4 alkyl groups, C1-4 alkoxy groups, C2-4 alkenyl groups, C2-4 alkynyl groups, and -NR. m2 R n2 Selected from nitro group, cyano group, azide group, oxo group, ester group and carboxyl group, t 1 It is selected from any integer between 0 and 10. Lg, L 1 , L 2 , L 3 , D, Rm2 , R n2 The definition is as described in any one form of this application.

[0037] In another embodiment, the present application provides a method for preparing a compound of formula II or a salt thereof.

[0038] [ka]

[0039] The process includes step i) reacting a compound of formula III or a salt thereof with a compound of formula X-3 or a salt thereof to obtain a compound of formula II or a salt thereof,

[0040] [ka]

[0041] In the formula, Lg, L 1 , L 2 , L 3 The definition of R8 is as described in any one form of this application.

[0042] In some embodiments, in step i), the compound represented by formula X-3 or a salt thereof is,

[0043] [ka]

[0044] Selected from this structure, the compound of formula II above or its salt is,

[0045] [ka]

[0046] This structure was selected, That is, step i) relates to a reaction in which a compound of formula III or a salt thereof is reacted with a compound of formula X-3a or a salt thereof to obtain a compound of formula IIa or a salt thereof.

[0047] [ka]

[0048] In another embodiment, the present application provides a method for preparing a compound of formula X-3 or a salt thereof. Step m-1) involves obtaining the compound of formula X-3-1 or its salt from the reaction of the compound of formula IV-2 or its salt,

[0049] [ka]

[0050] The process includes step m-2) reacting a compound of formula X-3-1 or a salt thereof with a compound of formula X-1 to obtain a compound of formula X-3 or a salt thereof,

[0051] [ka]

[0052] In the formula, E is a hydroxyl group, halogen, activated hydroxyl group, for example, a hydroxyl group, chlorine, bromine,

[0053] [ka]

[0054] Selected from, PG2 is selected from amino protecting groups, Lg, L 1 , L 2 , L 3 The definition of R8 is as described in any one form of this application.

[0055] In some embodiments, in steps m-1) and m-2), the compound represented by the above formula IV-2 or a salt thereof is

[0056]

Chemical formula

[0057] selected from the structures of, and correspondingly, the compound represented by the above formula X-3-1 or a salt thereof is

[0058]

Chemical formula

[0059] selected from the structures of, and correspondingly, the compound represented by the above formula X-3 or a salt thereof is

[0060]

Chemical formula

[0061] selected from the structures of, That is, step m-1) relates to a reaction of removing the protecting group Cbz from the compound of formula IV-2-A or a salt thereof under a metal reagent-hydrogen system to obtain the compound of formula X-3-1-A or a salt thereof.

[0062]

Chemical formula

[0063] Step m-2) relates to a reaction of reacting the compound of formula X-3-1-A or a salt thereof with the compound of formula X-1-A under basic conditions to obtain the compound of formula X-3a or a salt thereof.

[0064]

Chemical formula

[0065] In another embodiment, the present application provides a method for preparing a compound of formula IV-2 or a salt thereof. If R8 is not H, Step k-1) to obtain a compound of formula IV-2-1 or a salt thereof from the reaction of a compound of formula IV-1 or a salt thereof,

[0066] [ka]

[0067] The process includes step k-2), in which a compound of formula IV-2-1 or a salt thereof is reacted with a compound of formula IV-2-2 or a salt thereof to obtain a compound of formula IV-2 or a salt thereof.

[0068] [ka]

[0069] In the formula, PG2-L 3 That is, PG2-L 3-2 -L 3-1 And, If R8 is H, then IV-2 is IV-2a, which includes either Method 1 or Method 2 below: Method 1 is, The process includes step k-3) obtaining a compound of formula IV-2a or a salt thereof from the reaction of a compound of formula IV-2-3 or a salt thereof,

[0070] [ka]

[0071] Method 2 is, Step k-4) to obtain the compound of formula IV-2-5 or its salt from the reaction of the compound of formula IV-2-4 or its salt,

[0072] [ka]

[0073] Step k-5) of reacting a compound of formula IV-2-5 or a salt thereof with a compound of formula IV-2-2 or a salt thereof to obtain a compound of formula IV-2-6 or a salt thereof,

[0074]

Chemical formula

[0075] including step k-6) of obtaining a compound of formula IV-2a or a salt thereof from the reaction of a compound of formula IV-2-6 or a salt thereof,

[0076]

Chemical formula

[0077] In Method 2, PG2-L 3 is, that is, PG2-L 3-2 -L 3-1 and wherein L 3-1 is selected from an amino acid residue or a short peptide consisting of 2 to 9 amino acid residues, and the above amino acid residue is selected from a natural amino acid residue, a non-natural amino acid residue, or an amino acid residue shown in AA 1 or a stereoisomer thereof, PG1 is selected from an amino protecting group, L 3-2 is selected from an amino acid residue or a short peptide consisting of 2 to 9 amino acid residues, and the above amino acid residue is selected from a natural amino acid residue, a non-natural amino acid residue, or an amino acid residue shown in AA 1 or a stereoisomer thereof, L 3 The definitions of PG2, R8, and E are as described in any one form of the present application, PG3 is a hydroxy protecting group such as a benzyl group, a substituted benzyl group, or an allyl group.

[0078] In some embodiments, in steps k-1) and k-2), the compound of formula IV-1 or a salt thereof

[0079] [ka]

[0080] Selected from this structure, the compound of formula IV-2-2 or its salt is,

[0081] [ka]

[0082] Selected from this structure, the compound of formula IV-2-1 or its salt is,

[0083] [ka]

[0084] Selected from this structure, the compound or salt thereof shown in formula IV-2 above is,

[0085] [ka]

[0086] This structure was selected, That is, step k-1) relates to a reaction in which the protecting group Cbz is removed from the compound of formula IV-1-A or a salt thereof under a metal reagent-hydrogen system to obtain the compound of formula IV-2-1-A or a salt thereof.

[0087] [ka]

[0088] Step k-2) relates to a reaction in which a compound of formula IV-2-1-A or a salt thereof is reacted with a compound of formula IV-2-2-B or a salt thereof under basic or neutral conditions under the action of a condensing agent and / or a racemization inhibitor to obtain a compound of formula IV-2-A or a salt thereof.

[0089] [ka]

[0090] In another embodiment, the present application provides two methods for preparing compounds of formula IV-1 or salts thereof, comprising the following methods 1 or 2: Method 1 includes step j) reacting a compound of formula IV-1-1 or a salt thereof with a compound of formula R8OH or a salt thereof to obtain a compound of formula IV-1 or a salt thereof,

[0091] [ka]

[0092] Method 2 is, Step j-1) to obtain a compound or salt of formula IV-1-3 from the reaction of a compound or salt of formula IV-1-2,

[0093] [ka]

[0094] The process includes step j-2) obtaining a compound of formula IV-1 or a salt thereof from the reaction of a compound of formula IV-1-3 or a salt thereof,

[0095] [ka]

[0096] In the formula, L 3-1 The definitions of PG1 and R8 are as described in any one form of this application.

[0097] In some embodiments, in steps j-1) and j-2), the compound of formula IV-1-2 or a salt thereof is,

[0098] [ka]

[0099] Selected from this structure, the compound of formula IV-1-3 or its salt is,

[0100] [ka]

[0101] Selected from this structure, the compound of formula IV-1 or its salt is,

[0102] [ka]

[0103] This structure was selected, That is, step j-1) relates to a reaction in which a compound of formula IV-1-A-2 or a salt thereof is reacted with formaldehyde in water and under basic conditions to obtain a compound of formula IV-1-A-3 or a salt thereof.

[0104] [ka]

[0105] Step j-2) relates to a reaction in which a compound of formula IV-1-A-3 or a salt thereof is reacted with CF3CH2OH under acidic conditions to obtain a compound of formula IV-1-A or a salt thereof.

[0106] [ka]

[0107] In some embodiments, L 1 teeth,

[0108] [ka]

[0109] The first-place winner is connected to Lg, and the second-place winner is connected to L2.

[0110] In some embodiments, L 1 teeth

[0111] [ka]

[0112] The 1st place is linked to Lg, and the 2nd place is L 2 Connect to it.

[0113] In some embodiments, L 1 teeth

[0114] [ka]

[0115] The selection was made from, and the second place was L 2 Connect to it.

[0116] In some embodiments, L 2 teeth,

[0117] [ka]

[0118] Selected from, the winner is L 1 L is linked to 2nd place. 3 Connect to it.

[0119] In some embodiments, L 2 teeth,

[0120] [ka]

[0121] Selected from, the winner is L 1 L is linked to 2nd place.3 is connected to

[0122] In some embodiments, L 2 is

[0123]

Chemical formula

[0124] and the first position is connected to L 1 and the second position is connected to L 3 is connected to.

[0125] In some embodiments, Y is -CH2-.

[0126] In some embodiments, n4 is selected from 0, 1, 2, 3.

[0127] In some embodiments, Z is selected from -CH2-, -C(CH3)2-, -N(CH3)- and -NH-.

[0128] In some embodiments, R m , R n are each independently selected from H, a C1-4 alkyl group, a C2-4 alkenyl group, a C2-4 alkynyl group, a C3-6 cycloalkyl group, and a 3-6 member heterocyclic group,

[0129] or R m and R n together with the carbon atom to which they are both attached form a 3-6 member carbocyclic ring or a 3-6 member heterocyclic ring.

[0130] In some embodiments, R m , R n are each independently selected from H, Me.

[0131] In some embodiments, L 1 -L 2 is

[0132] [ka]

[0133] If selected from, the 1st place is linked to Lg, and the 2nd place is L 3 Connect to it.

[0134] In some embodiments, L 1 -L 2 teeth

[0135] [ka]

[0136] The selection was made from, and the second place was L 3 Connect to it.

[0137] In some embodiments, L 1 -L 2 teeth,

[0138] [ka]

[0139] Selected from, the 1st place is linked to Lg, and the 2nd place is linked to L 3 Connect to, and further

[0140] [ka]

[0141] You may choose from these options, and 2nd place is L 3 Connect to it.

[0142] In some embodiments, L 1 -L 2 teeth,

[0143] [ka]

[0144] Selected from, the 1st place is linked to Lg, and the 2nd place is linked to L 3 Connect to, and further

[0145] [ka]

[0146] You may choose from these options, and 2nd place is L 3 Connect to it.

[0147] In some embodiments, L 1 -L 2 teeth

[0148] [ka]

[0149] The 1st place is linked to Lg, and the 2nd place is L 3 Connect them.

[0150] In some embodiments, L 3 The peptide is selected from short peptides consisting of 2 to 4 amino acid residues, such as dipeptides, tripeptides, or tetrapeptides, and the above amino acid residues may be natural amino acid residues, unnatural amino acid residues, or AA 1 Selected from the amino acid residues shown or their stereoisomers.

[0151] In some embodiments, L 3 Val-Ala, AA 1 -Val-Ala, Val-AA 1 -Gly, Ala-AA 1 -Gly, Gly-AA 1 -Gly, Val-AA 1 -Ala, Val-AA 1 -Val, Ala-AA 1 -Ala, Ala-AA 1 -Val, Gly-AA 1 -Ala, Gly-AA 1-Selected from Val, Ala-Ala-Ala, Ala-Ala-Asn, Gly-Gly-Phe-Gly, and Gly-Gly-Val-Ala.

[0152] In some embodiments, L 3 Val-AA 1 -Gly, Ala-AA 1 -Gly, Gly-AA 1 -Gly, Val-AA 1 -Ala, Val-AA 1 -Val, Ala-AA 1 -Ala, Ala-AA 1 -Val, Gly-AA 1 -Ala, Gly-AA 1 -Selected from Val, Ala-Ala-Ala, Ala-Ala-Asn, and Gly-Gly-Phe-Gly.

[0153] In some embodiments, L 3 is Ala-Ala-Ala, Ala-Ala-Asn, Val-AA 1 -Selected from Gly and Gly-Gly-Phe-Gly.

[0154] In some embodiments, L 3 Val-AA 1 -Gly

[0155] In some embodiments, L 3 teeth,

[0156] [ka]

[0157] [ka]

[0158] Selected from, the winner is L 2 It connects to the first position, and the second position connects to NH.

[0159] In some embodiments, L 3 teeth,

[0160] [ka]

[0161] Selected from, the winner is L 2 It connects to the first position, and the second position connects to NH.

[0162] In some embodiments, L 3 teeth

[0163] [ka]

[0164] And the first place goes to L 2 It connects to the first position, and the second position connects to NH.

[0165] In some embodiments, R a , R b One of them is H, and the other is

[0166] [ka]

[0167] That is the case.

[0168] In some embodiments, R a and R b Together with the carbon atoms bonded to them, R 0 It forms a 5-6 membered heterocycle with substitutions.

[0169] In some embodiments, R a and R b Together with the carbon atoms bonded to them, R 0 It forms a piperidine ring or piperazine ring substituted with [the specified compound].

[0170] In some embodiments, R a and R b Together with the carbon atoms bonded to them, R 0 It forms a piperidine ring substituted with [a specific compound].

[0171] In some embodiments, R a and R b Together with the carbon atoms bonded to them,

[0172] [ka]

[0173] It forms, and the first carbon atom is R a and R b It is a carbon atom that is bonded together with it.

[0174] In some embodiments, r, r 1 Each of these is independently selected from 0, 1, 2, 3, 4, and 5.

[0175] In some embodiments, r, r 1 These are each independently selected from 0 and 4.

[0176] In some embodiments, r is 0, and r 1 It is 4.

[0177] In some embodiments, R m1 , R n1 Each of these is independently selected from H and C1-6 alkyl groups.

[0178] In some embodiments, R m1 , R n1 Each of these is independently selected from H, a methyl group, an ethyl group, an n-propyl group, and an n-butyl group.

[0179] In some embodiments, R m1 and R n1Together with the nitrogen atoms bonded to them, R is optionally formed. 0’ It forms a 5-6 membered heterocycle with substitutions.

[0180] In some embodiments, R m1 and R n1 Together with the nitrogen atoms bonded to them, R is optionally formed. 0’ It forms a piperidine ring or piperazine ring substituted with [the specified compound].

[0181] In some embodiments, R m1 and R n1 Together with the nitrogen atoms bonded to them,

[0182] [ka]

[0183] It forms, and the first nitrogen atom is R m1 and R n1 It is a nitrogen atom that is linked together with it.

[0184] In some embodiments, R 0 , R 0’ These are, independently, C1-6 alkyl groups and -NR. m2 R n2 And optionally selected from 5-6 membered heterocyclic groups substituted with C1-6 alkyl groups.

[0185] In some embodiments, R 0 The group is selected from C1-6 alkyl groups and 5-6 membered heterocyclic groups substituted with C1-6 alkyl groups, and the above 5-6 membered heterocyclic group is selected from piperidinyl groups and piperazinyl groups.

[0186] In some embodiments, R 0 The group is selected from a methyl group, an ethyl group, and a 5-6 membered heterocyclic group substituted with a methyl group, and the above 5-6 membered heterocyclic group is a piperidinyl group.

[0187] In some embodiments, R 0 These are a methyl group, an ethyl group, and

[0188] [ka]

[0189] Selected from.

[0190] In some embodiments, R 0’ These are C1-6 alkyl groups and -NR m2 R n2 Selected from.

[0191] In some embodiments, R 0’ The methyl group and -NR m2 R n2 Selected from.

[0192] In some embodiments, R m2 , R n2 It is a methyl group.

[0193] In some embodiments, AA 1 The structure of the amino acid residue shown is as follows:

[0194] [ka]

[0195] During the ceremony, R a , R b One of them is H, and the other is

[0196] [ka]

[0197] And r 1 It is 4, Alternatively, R a and R bTogether with the carbon atoms bonded to them, R 0 It forms a 5-6 member heterocycle substituted with, R m1 , R n1 Each of these is independently selected from H, C1-6 alkyl groups, and C3-6 cycloalkyl groups. R 0 These include C1-6 alkyl groups, C3-6 cycloalkyl groups, and -NR. m2 R n2 , and optionally selected from 5-6 membered heterocyclic groups substituted with C1-6 alkyl groups, R m2 , R n2 Each of these is independently selected from H and C1-6 alkyl groups.

[0198] In some embodiments, AA 1 The amino acid residues shown are,

[0199] [ka]

[0200] Selected from.

[0201] In some embodiments, AA 1 The amino acid residues shown are,

[0202] [ka]

[0203] Selected from.

[0204] In some embodiments, AA 1 The amino acid residues shown are

[0205] [ka]

[0206] That is the case.

[0207] In some embodiments, L 3-1 is selected from amino acid residues, and the above amino acid residues are

[0208] [ka]

[0209] Selected from, the winner is L 3-2 It connects to the first position, and the second position connects to NH.

[0210] In some embodiments, L 3-1 is selected from amino acid residues, and the above amino acid residues are

[0211] [ka]

[0212] Selected from, the winner is L 3-2 It connects to the first position, and the second position connects to NH.

[0213] In some embodiments, L 3-1 It is Gly.

[0214] In some embodiments, L 3-2 The amino acid residue is selected from an amino acid residue or a short peptide consisting of 2-3 amino acid residues, and the amino acid residue may be a natural amino acid residue, a non-natural amino acid residue, or AA. 1 Selected from the amino acid residues shown or their stereoisomers.

[0215] In some embodiments, L 3-2 Val, Val-AA 1 Ala-AA 1 Gly-AA 1 , Ala-Ala, AA 1 -Selected from Val, Gly-Gly-Val, and Gly-Gly-Phe.

[0216] In some embodiments, L 3-2 Val-AA 1 Ala-AA 1 Gly-AA 1 The following are selected: Ala-Ala and Gly-Gly-Phe.

[0217] In some embodiments, L 3-2 Val-AA 1 The following are selected: Ala-Ala and Gly-Gly-Phe.

[0218] In some embodiments, L 3-2 Val-AA 1 That is the case.

[0219] In some embodiments, L 3-2 teeth,

[0220] [ka]

[0221] Selected from, the winner is L 2 L is linked to 2nd place. 3-1 Connect to it.

[0222] In some embodiments, L 3-2 teeth,

[0223] [ka]

[0224] Selected from, the winner is L 2 L is linked to 2nd place. 3-1 Connect to it.

[0225] In some embodiments, L 3-2 teeth

[0226] [ka]

[0227] And the first place goes to L 2 L is linked to 2nd place. 3-1 Connect to it.

[0228] In some embodiments, PG1 and PG2 are independently selected from a benzyloxycarbonyl group (Cbz), a tert-butoxycarbonyl group (Boc), a 9-fluorenylmethoxycarbonyl group (Fmoc), an allyloxycarbonyl group (Alloc), a trimethylsilylethoxycarbonyl group (Teoc), a methoxycarbonyl group, or an ethoxycarbonyl group.

[0229] In some embodiments, PG1 and PG2 are independently selected from a benzyloxycarbonyl group (Cbz), a 9-fluorenylmethoxycarbonyl group (Fmoc), and an allyloxycarbonyl group (Alloc).

[0230] In some embodiments, PG1 and PG2 are 9-fluorenylmethoxycarbonyl groups (Fmoc).

[0231] In some embodiments, PG1 and PG2 are benzyloxycarbonyl groups (Cbz).

[0232] In some embodiments, R8 is selected from hydrogen, C1-30 alkyl groups, C3-7 cycloalkyl groups, 3-20 membered heterocyclic groups, C1-6 alkyl-C3-6 cycloalkyl groups, C1-6 alkyl-4-6 membered heterocyclic groups, C1-6 alkyl-C5-10 heteroaryl groups, and C1-6 alkyl-C6-10 aryl groups, where the alkyl groups, cycloalkyl groups, heterocyclic groups, and aryl groups are optionally selected from one or more R8s. x It will be replaced by this.

[0233] In some embodiments, R8 is selected from hydrogen, C1-30 alkyl groups (e.g., C1-6 alkyl groups), and C1-6 alkyl-C6-10 aryl groups, where the alkyl and aryl groups are optionally one or more Rx It will be replaced by this.

[0234] In some embodiments, R8 is selected from hydrogen, a methyl group, an ethyl group, an isopropyl group, a tert-butyl group, 2,2,2-trifluoroethyl, 2,2,3,3,3-pentafluoro-1-propyl, and a benzyl group.

[0235] In some embodiments, R8 is selected from hydrogen, isopropyl group, tert-butyl group, 2,2,2-trifluoroethyl, 2,2,3,3,3-pentafluoro-1-propyl, and benzyl group.

[0236] In some embodiments, R x The group is selected from hydrogen, deuterium, fluorine, chlorine, bromine, methyl group, methoxy group, amino group, dimethylamino group, nitro group, cyano group, and azide group.

[0237] In some embodiments, R x The group is selected from hydrogen, fluorine, methyl group, and methoxy group.

[0238] In some embodiments, PG3 is one or more R Y Selected from benzyl groups substituted with .

[0239] In some embodiments, PG3 is selected from a benzyl group and a p-methoxybenzyl group.

[0240] In some embodiments, R Y The group is selected from hydrogen, fluorine, chlorine, bromine, methyl group, methoxy group, dimethylamino group, and nitro group.

[0241] In some embodiments, in step i), the compound of formula III or a salt thereof is reacted with the compound of formula X-3 or a salt thereof after azeotropic dehydration to obtain the compound of formula II or a salt thereof.

[0242] In some embodiments, in step i), the azeotropic solvent is selected from toluene, xylene, chloroform, acetonitrile, ethyl acetate, and dichloroethane, and is preferably toluene or xylene.

[0243] In some embodiments, in step i), the compound of formula III or a salt thereof and the compound of formula X-3 or a salt thereof are converted under conditions without the addition of acid to obtain the compound of formula II or a salt thereof, and the reaction temperature is selected from 110 to 150°C, preferably 120 to 130°C.

[0244] In some embodiments, in step i), the compound of formula III or a salt thereof and the compound of formula X-3 or a salt thereof are obtained under acidic conditions to obtain the compound of formula II or a salt thereof.

[0245] In some embodiments, in step i), the compound of formula III or a salt thereof and the compound of formula X-3 or a salt thereof are converted under acidic conditions to obtain the compound of formula II or a salt thereof, and the reaction temperature is selected from 15 to 40°C, preferably 20 to 35°C.

[0246] In some embodiments, in step i), the acid is a protonic or aprotonic acid, such as hydrogen chloride, hydrobromic acid, sulfuric acid, boron trifluoride diethyl ether, p-toluenesulfonic acid, pyridinium salt of p-toluenesulfonate, zinc acetate, aluminum trichloride (AlCl3), ferric chloride (FeCl3), ytterbium trifluoromethanesulfonate (Yb(OTf)3) triethylamine hydrochloride, boron trifluoride acetonitrile, boron trifluoride tetrahydrofuran, pyridine hydrogen chloride, pyridine hydrogen bromide The din is preferably hydrogen chloride, hydrobromic acid, sulfuric acid, trifluoroacetic acid, p-toluenesulfonic acid, pyridinium salt of p-toluenesulfonate, zinc acetate, aluminum trichloride (AlCl3), ferric chloride (FeCl3), boron trifluoride diethyl ether (BF3·Et2O), and ytterbium trifluoromethanesulfonate (Yb(OTf)3), and also, for example, hydrogen chloride or boron trifluoride diethyl ether, more preferably hydrogen chloride, sulfuric acid, and most preferably boron trifluoride diethyl ether.

[0247] In some embodiments, in step i), the molar ratio of the compound of formula III or its salt to the acid selected for the reaction is selected from 1:0.2 to 1:6, preferably 1:2 to 1:5, for example 1:2.5, 1:3, or 1:5.

[0248] In some embodiments, in step i), the molar ratio of the compound of formula III or its salt to the compound of formula X-3 or its salt is selected from 1:1 to 1:5, and preferably 1:2 to 1:3.

[0249] In some embodiments, in step i), the reaction solvent is selected from one of ether-based solvents, nitrile-based solvents, amide-based solvents, sulfonate-based solvents, or water, or any combination thereof, preferably an amide-based or sulfonate-based solvent, more preferably N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), N-methylpyrrolidone (NMP), or dimethyl sulfoxide (DMSO), and even more preferably N,N-dimethylformamide.

[0250] In some embodiments, in step i), the mass-volume ratio (g / mL) of the compound of formula III or its salt to the selected solvent is selected from 1:2 to 1:10, and preferably 1:2.5 to 1:7.

[0251] In some embodiments, in step i), the reaction temperature is selected from 0 to 80°C, preferably 15 to 40°C, and more preferably 25 to 35°C.

[0252] In some embodiments, in step j), the compound of formula IV-1-1 or a salt thereof and the compound of formula R8OH or a salt thereof are obtained under acidic or basic conditions to obtain the compound of formula IV-1 or a salt thereof.

[0253] In some embodiments, in step j), the acid is a protonic or aprotonic acid, preferably hydrogen chloride, hydrobromic acid, sulfuric acid, trifluoroacetic acid, p-toluenesulfonic acid, pyridinium salt of p-toluenesulfonate, zinc acetate, aluminum trichloride (AlCl3), ferric chloride (FeCl3), boron trifluoride diethyl ether (BF3·Et2O), and ytterbium trifluoromethanesulfonate (Yb(OTf)3), and more preferably hydrogen chloride, sulfuric acid, zinc acetate, for example, hydrogen chloride.

[0254] In some embodiments, in step j), the base is an organic or inorganic base, preferably sodium hydroxide, potassium tert-butoxide, potassium carbonate, triethylamine (Et3N), N,N-diisopropylethylamine (DIPEA), and pyridine, and preferably potassium tert-butoxide.

[0255] In some embodiments, in step j), the molar ratio of the compound of formula IV-1-1 or its salt to the acid selected for the reaction is selected from 1:0.01 to 1:0.2, for example, 1:0.05.

[0256] In some embodiments, in step j), the molar ratio of the compound of formula IV-1-1 or its salt to the base selected for the reaction is selected from 1:0.9 to 1:5.

[0257] In some embodiments, in step j), the molar ratio of the compound of formula IV-1-1 or a salt thereof to the compound of formula R8OH or a salt thereof is selected from 1:1 to 1:20, and preferably 1:2 to 1:15.

[0258] In some embodiments, in step j), the reaction solvent is selected from alcoholic, etheric, haloalkaneic, aromatic hydrocarbon, nitrile, amide, or sulfoneic solvents, more preferably isopropanol, benzyl alcohol, tert-butanol, 2,2,2-trifluoroethanol, 2,2,3,3,3-pentafluoro-1-propanol, ethylene glycol diethyl ether, tetrahydrofuran, 1,4-dioxane, dichloromethane, 1,2-dichloroethane, toluene, acetonitrile, DMF, DMAc, NMP, or DMSO, and even more preferably isopropanol, benzyl alcohol, tert-butanol, 2,2,2-trifluoroethanol, 2,2,3,3,3-pentafluoro-1-propanol, toluene, tetrahydrofuran, acetonitrile, DMF, DMAc, NMP, for example, 2,2,2-trifluoroethanol, DMF.

[0259] In some embodiments, in step j), the mass-volume ratio (g / mL) of the compound of formula IV-1-1 or its salt to the selected solvent is selected from 1:2 to 1:10, and preferably 1:2.5 to 1:7.

[0260] In some embodiments, in step j), the reaction temperature is selected from 0 to 120°C, for example, 10 to 50°C.

[0261] In some embodiments, in step j-1), the compound of formula IV-1-2 or a salt thereof reacts with formaldehyde in water and under basic conditions to obtain the compound of formula IV-1-3 or a salt thereof.

[0262] In some embodiments, in step j-1), the base is selected from potassium carbonate, potassium bicarbonate, potassium phosphate, sodium carbonate, sodium bicarbonate, triethylamine, diisopropylethylamine, and the like, and is preferably potassium carbonate.

[0263] In some embodiments, in step j-1), the molar ratio of the compound of formula IV-1-2 or its salt to the base is 1:0.05 to 1:1, preferably 1:0.1 to 1:0.5.

[0264] In some embodiments, in step j-1), the molar ratio of the compound of formula IV-1-2 or its salt to formaldehyde is 1:0.5 to 1:2.5, preferably 1:1 to 1:2, for example 1:1.8.

[0265] In some embodiments, in step j-1), the mass-volume ratio (g / mL) of the compound of formula IV-1-2 or its salt to water is 1:3 to 1:50, preferably 1:5 to 1:20, for example 1:15.

[0266] In some embodiments, in step j-1), the reaction temperature is 0 to 80°C, preferably 10 to 50°C.

[0267] In some embodiments, in step j-2), the compound of formula IV-1-3 or a salt thereof reacts with the compound of formula R8OH or a salt thereof under acidic conditions to obtain the compound of formula IV-1 or a salt thereof.

[0268] In some embodiments, in step j-2), the acid is a protonic or aprotonic acid, preferably hydrogen chloride, hydrobromic acid, sulfuric acid, trifluoroacetic acid, p-toluenesulfonic acid, pyridinium salt of p-toluenesulfonate, zinc acetate, aluminum trichloride (AlCl3), ferric chloride (FeCl3), boron trifluoride diethyl ether (BF3·Et2O), and ytterbium trifluoromethanesulfonate (Yb(OTf)3), and more preferably hydrogen chloride, sulfuric acid, zinc acetate, for example, hydrogen chloride.

[0269] In some embodiments, in step j-2), the molar ratio of the compound of formula IV-1-3 or its salt to the acid selected for the reaction is selected from 1:0.01 to 1:0.2, for example, 1:0.05.

[0270] In some embodiments, in step j-2), the molar ratio of the compound of formula IV-1-3 or its salt to the compound of formula R8OH or its salt is selected from 1:1 to 1:50, and preferably 1:2 to 1:30.

[0271] In some embodiments, in step j-2), the reaction solvent is selected from alcoholic, etheric, haloalkaneic, aromatic hydrocarbon, nitrile, amide, or sulfoneic solvents, more preferably isopropanol, benzyl alcohol, tert-butanol, 2,2,2-trifluoroethanol, 2,2,3,3,3-pentafluoro-1-propanol, ethylene glycol diethyl ether, tetrahydrofuran, 1,4-dioxane, dichloromethane, 1,2-dichloroethane, toluene, acetonitrile, DMF, DMAc, NMP, or DMSO, and even more preferably isopropanol, benzyl alcohol, tert-butanol, 2,2,2-trifluoroethanol, 2,2,3,3,3-pentafluoro-1-propanol, toluene, tetrahydrofuran, acetonitrile, DMF, DMAc, NMP, for example, 2,2,2-trifluoroethanol, DMF.

[0272] In some embodiments, in step j-2), the mass-volume ratio (g / mL) of the compound of formula IV-1-3 or its salt to the selected solvent is selected from 1:2 to 1:10, and preferably 1:2.5 to 1:7.

[0273] In some embodiments, in step j-2), the reaction temperature is selected from 0 to 120°C, for example, 0 to 50°C.

[0274] In some embodiments, in step k-1), the protecting group PG1 on the amino group is removed from the compound of formula IV-1 or a salt thereof to obtain the compound of formula IV-2-1 or a salt thereof.

[0275] In some embodiments, the reaction in step k-1) to remove the protecting group PG1 on the amino group from the compound of formula IV-1 or a salt thereof can be carried out using conventional reaction conditions well known to those skilled in the art, for example, removal under acidic conditions, the acid including protic and aprotic acids; removal under basic conditions, the base including organic and inorganic bases; and removal under metallic reagent conditions, the metallic reagent preferably selected from palladium-based reagents or platinum-based reagents, and more preferably selected from palladium-carbon, platinum-carbon, platinum dioxide, and palladium hydroxide.

[0276] In some embodiments, if in step k-1) the PG1 is a 9-fluorenylmethoxycarbonyl group (Fmoc), the compound of formula IV-1 or a salt thereof removes the protecting group PG1 under basic conditions. The base is selected from organic or inorganic bases, preferably piperidine, diethylamine, morpholine, diisopropylamine, DBU, triethylamine, and N,N-diisopropylethylamine, more preferably piperidine, diethylamine, or morpholine, such as diethylamine or DBU.

[0277] In some embodiments, when PG1 is a 9-fluorenylmethoxycarbonyl group (Fmoc) in step k-1), the molar ratio of the compound of formula IV-1 or its salt to the selected base is selected from 1:0.2 to 1:40, for example, 1:0.2 to 1:2, preferably 1:1 to 1:10, for example, 1:0.4.

[0278] In some embodiments, when the PG1 in step k-1) is a 9-fluorenylmethoxycarbonyl group (Fmoc), the reaction solvent is selected from one of DMF, DMAc, NMP, dichloromethane, tetrahydrofuran, 1,4-dioxane, acetonitrile, or any combination thereof, for example, DMF or tetrahydrofuran.

[0279] In some embodiments, when PG1 is a 9-fluorenylmethoxycarbonyl group (Fmoc) in step k-1), the mass volume ratio (g / mL) of the compound of formula IV-1 or its salt to the selected reaction solvent is selected from 1:5 to 1:50, and preferably 1:6 to 1:20.

[0280] In some embodiments, when the PG1 in step k-1) is a 9-fluorenylmethoxycarbonyl group (Fmoc), the reaction temperature is selected from 0 to 50°C, preferably 15 to 30°C.

[0281] In some embodiments, if in step k-1) the PG1 is a benzyloxycarbonyl group (Cbz), the compound of formula IV-1 or a salt thereof removes the protecting group PG1 under a metal reagent-hydrogen system. The metal reagent is selected from palladium-based reagents or platinum-based reagents, preferably palladium carbon, platinum carbon, platinum dioxide, palladium hydroxide, for example, palladium carbon or palladium hydroxide.

[0282] In some embodiments, when PG1 is a benzyloxycarbonyl group (Cbz) in step k-1), the mass ratio of the compound of formula IV-1 to the metal reagent is 1:0.01 to 1, preferably 1:0.03 to 0.5, for example 1:0.05 or 1:0.1.

[0283] In some embodiments, when PG1 in step k-1) is a benzyloxycarbonyl group (Cbz), the hydrogen gas used is 1 atm to 50 atm.

[0284] In some embodiments, when the PG1 in step k-1) is a benzyloxycarbonyl group (Cbz), the reaction temperature is 0°C to 100°C, preferably 20°C to 70°C.

[0285] In some embodiments, when PG1 in step k-1) is a benzyloxycarbonyl group (Cbz), the reaction solvent is selected from any one of alcohols, ethers, esters, amides, or water, or a mixture of any proportion of the above substances, preferably methanol, ethanol, tetrahydrofuran, ethyl acetate, DMF, DMAc, NMP, or water, for example methanol or tetrahydrofuran.

[0286] In some embodiments, when PG1 is a benzyloxycarbonyl group (Cbz) in step k-1), the mass-volume ratio (g / mL) of the compound of formula IV-1 or its salt to the selected reaction solvent is selected from 1:3 to 1:20, and preferably 1:5 to 1:10.

[0287] In some embodiments, if in step k-1) the PG1 is an allyloxycarbonyl group (Alloc), the compound of formula IV-1 or a salt thereof removes the protecting group PG1 under the conditions of a metal reagent. The metal reagent is selected from palladium-based reagents, preferably tetrakistriphenylphosphine palladium or bistriphenylphosphine dichloropalladium.

[0288] In some embodiments, in step k-2), a compound of formula IV-2 is obtained by a condensation reaction between a compound of formula IV-2-1 or a salt thereof and a compound of formula IV-2-2 or a salt thereof.

[0289] In some embodiments, when E is a hydroxyl group in step k-2), the reaction proceeds under basic or neutral conditions under the action of a condensing agent and / or a racemization inhibitor, the condensing agent being a reagent well known to those skilled in the art, preferably DMTMM, HATU, HBTU, EDCI, COMU, N-ethynyl-N-methylmethanesulfonamide, EEDQ, and T3P, and more preferably DMTMM and HBTU.

[0290] In some embodiments, when E is a hydroxyl group in step k-2), the racemization inhibitor is selected from HOAt and HOBt.

[0291] In some embodiments, when E is a hydroxyl group in step k-2), the base is selected from DBU, triethylamine, N,N-diisopropylethylamine, and N-methylmorpholine.

[0292] In some embodiments, when E is a hydroxyl group in step k-2), the molar ratio of the compound of formula IV-2-2 or its salt to the condensing agent is selected from 1:1 to 1:5, preferably 1:1 to 1:1.5.

[0293] In some embodiments, when E is a hydroxyl group in step k-2), the molar ratio of the compound of formula IV-2-1 or its salt to the compound of formula IV-2-2 or its salt is selected from 1:0.8 to 1:3, and preferably 1:0.8 to 1:1.2.

[0294] In some embodiments, when E is a hydroxyl group in step k-2), the reaction solvent is selected from one of DMF, acetonitrile, tetrahydrofuran, methanol, dichloromethane, and water, or any combination thereof, preferably DMF or tetrahydrofuran.

[0295] In some embodiments, when E is a hydroxyl group in step k-2), the mass-volume ratio (g / mL) of the compound of formula IV-2-1 or its salt to the selected reaction solvent is selected from 1:5 to 1:20.

[0296] In some embodiments, when E is a hydroxyl group in step k-2), the reaction temperature is selected from -20 to 100°C, preferably -15 to 50°C, and most preferably lower than -15°C.

[0297] In some embodiments, when E is an activated hydroxyl group in step k-2), the compound of formula IV-2-1 or a salt thereof reacts with the compound of formula IV-2-2 or a salt thereof under basic or neutral conditions, the base being selected from organic or inorganic bases, preferably triethylamine, N,N-diisopropylethylamine, DBU, and N-methylmorpholine.

[0298] In some embodiments, when E is an activated hydroxyl group in step k-2), the reaction solvent is selected from one of DMF, tetrahydrofuran, and dichloromethane, or any combination thereof.

[0299] In some embodiments, when E is an activated hydroxyl group in step k-2), the molar ratio of the compound of formula IV-2-1 or its salt to the compound of formula IV-2-2 or its salt is selected from 1:0.8 to 1:1.2.

[0300] In some embodiments, in step k-3), the compound of formula IV-2-3 or a salt thereof is reacted with an aldehyde reagent under basic conditions to obtain the compound of formula IV-2a or a salt thereof.

[0301] In some embodiments, in step k-3), the aldehyde reagent is selected from aqueous formaldehyde, metaformaldehyde, and paraformaldehyde.

[0302] In some embodiments, in step k-3), the base is an inorganic base, preferably potassium carbonate, sodium carbonate, sodium bicarbonate, potassium bicarbonate, potassium tert-butoxide, potassium phosphate, dipotassium hydrogen phosphate, or dihydrogen dipotassium phosphate.

[0303] In some embodiments, in step k-3), the molar ratio of the compound of formula IV-2-3 or its salt to the aldehyde reagent is selected from 1:20 to 1:200, preferably 1:40 to 1:90.

[0304] In some embodiments, in step k-3), the reaction solvent is selected from one of alcohols, ethers, nitriles, amides, or water, or any combination thereof, preferably one of methanol, ethanol, tetrahydrofuran, 1,4-dioxane, acetonitrile, DMF, or any combination thereof.

[0305] In some embodiments, in step k-3), the reaction temperature is selected from 25 to 100°C, preferably 25 to 80°C.

[0306] In some embodiments, in step k-4), the protecting group PG1 on the amino group is removed from the compound of formula IV-2-4 or a salt thereof to obtain the compound of formula IV-2-5 or a salt thereof.

[0307] In some embodiments, the reaction in step k-4) to remove the protecting group PG1 on the amino group from the compound of formula IV-2-4 or a salt thereof can be carried out using conventional reaction conditions well known to those skilled in the art, for example, removal under acidic conditions, removal under basic conditions, or removal under metallic reagent conditions.

[0308] In some embodiments, if in step k-4) the PG1 is a 9-fluorenylmethoxycarbonyl group (Fmoc), the compound of formula IV-2-4 or a salt thereof removes the protecting group PG1 under basic conditions. The base is selected from organic or inorganic bases, preferably piperidine, diethylamine, morpholine, diisopropylamine, or DBU, and more preferably diethylamine.

[0309] In some embodiments, when PG1 is a 9-fluorenylmethoxycarbonyl group (Fmoc) in step k-4), the molar ratio of the compound of formula IV-2-4 or its salt to the selected base is selected from 1:0.2 to 1:40, and preferably 1:1 to 1:10.

[0310] In some embodiments, when the PG1 in step k-4) is a 9-fluorenylmethoxycarbonyl group (Fmoc), the reaction solvent is selected from DMF, DMAc, NMP, dichloromethane, tetrahydrofuran, 1,4-dioxane, and acetonitrile, and is preferably DMF.

[0311] In some embodiments, when PG1 is a 9-fluorenylmethoxycarbonyl group (Fmoc) in step k-4), the mass volume ratio (g / mL) of the compound of formula IV-2-4 or its salt to the selected reaction solvent is selected from 1:5 to 1:50, and preferably 1:6 to 1:20.

[0312] In some embodiments, when the PG1 in step k-4) is a 9-fluorenylmethoxycarbonyl group (Fmoc), the reaction temperature is selected from 0 to 50°C, preferably 15 to 30°C.

[0313] In some embodiments, in step k-4), if PG1 is a benzyloxycarbonyl group (Cbz), the compound of formula IV-2-4 or a salt thereof removes the protecting group PG1 under a metal reagent-hydrogen system. The metal reagent is selected from palladium-based reagents or platinum-based reagents, preferably palladium carbon, platinum carbon, platinum dioxide, or palladium hydroxide.

[0314] In some embodiments, in step k-4), if PG1 is an allyloxycarbonyl group (Alloc), the compound of formula IV-2-4 or a salt thereof removes the protecting group PG1 under palladium reagent conditions. The metal reagent is selected from palladium-based reagents, preferably tetrakistriphenylphosphine palladium or bistriphenylphosphine dichloropalladium.

[0315] In some embodiments, in step k-5), a compound of formula IV-2-6 is obtained by a condensation reaction between a compound of formula IV-2-5 or a salt thereof and a compound of formula IV-2-2 or a salt thereof.

[0316] In some embodiments, when E is a hydroxyl group in step k-5), the reaction proceeds under basic or neutral conditions under the action of a condensing agent and / or a racemization inhibitor, the condensing agent being a reagent well known to those skilled in the art, preferably DMTMM, HATU, HBTU, EDCI, COMU, N-ethynyl-N-methylmethanesulfonamide, EEDQ, and T3P, and more preferably DMTMM and HBTU.

[0317] In some embodiments, when E is a hydroxyl group in step k-5), the racemization inhibitor is selected from HOAt and HOBt.

[0318] In some embodiments, when E is a hydroxyl group in step k-5), the base is selected from triethylamine, N,N-diisopropylethylamine, and N-methylmorpholine.

[0319] In some embodiments, when E is a hydroxyl group in step k-5), the molar ratio of the compound of formula IV-2-2 or its salt to the condensing agent is selected from 1:1 to 1:5, preferably 1:1 to 1:1.5.

[0320] In some embodiments, when E is a hydroxyl group in step k-5), the molar ratio of the compound of formula IV-2-5 or its salt to the compound of formula IV-2-2 or its salt is selected from 1:0.8 to 1:1.2.

[0321] In some embodiments, when E is a hydroxyl group in step k-5), the reaction solvent is selected from one of DMF, acetonitrile, tetrahydrofuran, methanol, dichloromethane, and water, or any combination thereof, and is preferably DMF.

[0322] In some embodiments, when E is a hydroxyl group in step k-5), the mass-volume ratio (g / mL) of the compound of formula IV-2-5 or its salt to the selected reaction solvent is selected from 1:5 to 1:20.

[0323] In some embodiments, when E is a hydroxyl group in step k-5), the reaction temperature is selected from -20 to 100°C, preferably -15 to 50°C.

[0324] In some embodiments, when E is an activated hydroxyl group in step k-5), the compound of formula IV-2-5 or a salt thereof reacts with the compound of formula IV-2-2 or a salt thereof under basic or neutral conditions, the base being selected from organic or inorganic bases, preferably triethylamine, N,N-diisopropylethylamine, and N-methylmorpholine.

[0325] In some embodiments, when E is an activated hydroxyl group in step k-5), the reaction solvent is selected from one of DMF, acetonitrile, tetrahydrofuran, dichloromethane, and water, or any combination thereof.

[0326] In some embodiments, when E is an activated hydroxyl group in step k-5), the molar ratio of the compound of formula IV-2-5 or its salt to the compound of formula IV-2-2 or its salt is selected from 1:0.8 to 1:1.2.

[0327] In some embodiments, in step k-6), the compound of formula IV-2-6 or a salt thereof is subjected to a metal catalyst-hydrogen system under acidic conditions to remove the protecting group on the hydroxyl group and obtain the compound of formula IV-2a.

[0328] In some embodiments, in step k-6), the acid is a protic acid, preferably formic acid, acetic acid, trifluoroacetic acid, or hydrochloric acid.

[0329] In some embodiments, in step k-6), the molar ratio of the compound of formula IV-2-6 or its salt to the acid is 1:0.2 to 1:2.

[0330] In some embodiments, in step k-6), the metal catalyst is selected from palladium-carbon, platinum-carbon, platinum dioxide, and palladium hydroxide.

[0331] In some embodiments, in step k-6), the ratio of the compound of formula IV-2-6 or its salt to the metal catalyst is 0.5% to 20%.

[0332] In some embodiments, in step k-6), the hydrogen source is selected from hydrogen gas and formic acid.

[0333] In some embodiments, in step k-6), the hydrogen source pressure is selected from 1 to 5 atm.

[0334] In some embodiments, in step k-6), the reaction solvent is selected from one of DMF, acetonitrile, tetrahydrofuran, methanol, and ethyl acetate, or any combination thereof.

[0335] In some embodiments, in step m-1), the protecting group PG2 on the amino group is removed from the compound of formula IV-2 or a salt thereof to obtain the compound of formula X-3-1 or a salt thereof.

[0336] In some embodiments, the reaction in step m-1) to remove the protecting group PG2 on the amino group from the compound of formula IV-2 or a salt thereof can be carried out using conventional reaction conditions well known to those skilled in the art, for example, removal under acidic conditions, the acid including protic and aprotic acids; removal under basic conditions, the base including organic and inorganic bases; and removal under metallic reagent conditions, the metallic reagent preferably selected from palladium-based reagents or platinum-based reagents, and more preferably selected from palladium-carbon, platinum-carbon, platinum dioxide, and palladium hydroxide.

[0337] In some embodiments, if in step m-1) the PG2 is a 9-fluorenylmethoxycarbonyl group (Fmoc), the compound of formula IV-2 or a salt thereof removes the protecting group PG2 under basic conditions. The base is selected from piperidine, diethylamine, morpholine, and DBU, and is preferably diethylamine.

[0338] In some embodiments, when the PG2 in step m-1) is a 9-fluorenylmethoxycarbonyl group (Fmoc), the molar ratio of the compound of formula IV-2 or its salt to the selected base is selected from 1:0.2 to 1:40, and preferably 1:1 to 1:10.

[0339] In some embodiments, when the PG2 in step m-1) is a 9-fluorenylmethoxycarbonyl group (Fmoc), the reaction solvent is selected from DMF, dichloromethane, tetrahydrofuran, and 1,4-dioxane, and is preferably DMF.

[0340] In some embodiments, when the PG2 in step m-1) is a 9-fluorenylmethoxycarbonyl group (Fmoc), the mass volume ratio (g / mL) of the compound of formula IV-2 or its salt to the selected reaction solvent is selected from 1:5 to 1:50, and preferably 1:6 to 1:20.

[0341] In some embodiments, when the PG2 in step m-1) is a 9-fluorenylmethoxycarbonyl group (Fmoc), the reaction temperature is selected from 0 to 50°C, preferably 15 to 30°C.

[0342] In some embodiments, if in step m-1) the PG2 is a benzyloxycarbonyl group (Cbz), the compound of formula IV-2 or a salt thereof removes the protecting group PG2 under a metal reagent-hydrogen system. The metal reagent is a palladium-based reagent or a platinum-based reagent, preferably palladium carbon, platinum carbon, platinum dioxide, palladium hydroxide, for example, palladium carbon or palladium hydroxide.

[0343] In some embodiments, when the PG2 in step m-1) is a benzyloxycarbonyl group (Cbz), the mass ratio of the compound of formula IV-2 to the metal reagent is 1:0.01 to 1, preferably 1:0.03 to 0.5, for example 1:0.3.

[0344] In some embodiments, when the PG2 in step m-1) is a benzyloxycarbonyl group (Cbz), the hydrogen gas used is 1 atm to 50 atm, preferably 1 to 4 atm.

[0345] In some embodiments, when the PG2 in step m-1) is a benzyloxycarbonyl group (Cbz), the reaction temperature is 0°C to 100°C, preferably 20°C to 70°C.

[0346] In some embodiments, when the PG2 in step m-1) is a benzyloxycarbonyl group (Cbz), the reaction solvent is selected from any one of alcohols, ethers, esters, amides, or water, or a mixture of any proportion of the above substances, preferably methanol, ethanol, tetrahydrofuran, ethyl acetate, DMF, DMAc, NMP, or water, for example methanol or tetrahydrofuran.

[0347] In some embodiments, when PG2 is a benzyloxycarbonyl group (Cbz) in step m-1), the mass volume ratio (g / mL) of the compound of formula IV-2 or its salt to the selected reaction solvent is selected from 1:3 to 1:50, and preferably 1:10 to 1:30.

[0348] In some embodiments, if in step m-1) the PG2 is an allyloxycarbonyl group (Alloc), the compound of formula IV-2 or a salt thereof removes the protecting group PG2 under the conditions of a metal reagent. The metal reagent is a palladium-based reagent, preferably tetrakistriphenylphosphine palladium or bistriphenylphosphine dichloropalladium.

[0349] In some embodiments, in step m-2), a compound of formula X-3 or a salt thereof is obtained by a condensation reaction between a compound of formula X-3-1 or a salt thereof and a compound of formula X-1 or a salt thereof.

[0350] In some embodiments, when E is a hydroxyl group in step m-2), the reaction proceeds under basic or neutral conditions under the action of a coupling agent, the coupling agent being a reagent well known to those skilled in the art, preferably DMTMM, HATU, HBTU, COMU, N-ethynyl-N-methylmethanesulfonamide, and more preferably DMTMM, HBTU.

[0351] In some embodiments, when E is a hydroxyl group in step m-2), the base is selected from organic or inorganic bases, preferably triethylamine, N,N-diisopropylethylamine, N-methylmorpholine, and preferably N,N-diisopropylethylamine.

[0352] In some embodiments, when E is a hydroxyl group in step m-2), the molar ratio of the compound of formula X-1 or its salt to the condensing agent is selected from 1:1 to 1:5, preferably 1:1 to 1:1.5.

[0353] In some embodiments, when E is a hydroxyl group in step m-2), the molar ratio of the compound of formula X-3-1 or its salt to the compound of formula X-1 or its salt is selected from 1:0.9 to 1:1.2.

[0354] In some embodiments, when E is a hydroxyl group in step m-2), the reaction solvent is selected from one of DMF, acetonitrile, tetrahydrofuran, methanol, dichloromethane, and water, or any combination thereof, and is preferably DMF.

[0355] In some embodiments, when E is a hydroxyl group in step m-2), the reaction temperature is selected from -20 to 100°C, for example -20 to 30°C, preferably 0 to 30°C.

[0356] In some embodiments, when E is selected from halogens (e.g., chlorine, fluorine, or bromine) in step m-2), the compound of formula X-3-1 or a salt thereof reacts with the compound of formula X-1 or a salt thereof under basic conditions. The base is selected from triethylamine, N,N-diisopropylethylamine, DBU, and N-methylmorpholine, and is preferably N,N-diisopropylethylamine.

[0357] In some embodiments, when E is selected from halogens (e.g., chlorine, fluorine, or bromine) in step m-2), the molar ratio of the compound of formula X-1 or its salt to the base described in the reaction is selected from 1:0.1 to 1:5, for example, 1:1 to 1:5, preferably 1:0.2 to 1:1.

[0358] In some embodiments, when E is a halogen (e.g., chlorine, fluorine, or bromine) in step m-2), the molar ratio of the compound of formula X-1 or its salt to the compound of formula X-3-1 or its salt is selected from 1:0.8 to 1:2.0, and preferably 1:0.9 to 1:1.2.

[0359] In some embodiments, when E is a halogen (e.g., chlorine, fluorine, or bromine) in step m-2), the reaction solvent is selected from one of DMF, tetrahydrofuran, dichloromethane, acetonitrile, or any combination thereof, and is preferably acetonitrile.

[0360] In some embodiments, when E is a halogen (e.g., chlorine, fluorine, or bromine) in step m-2), the mass-volume ratio (g / mL) of the compound of formula X-1 or its salt to the selected reaction solvent is selected from 1:2 to 1:50, and preferably 1:3 to 1:10.

[0361] In some embodiments, when E is a halogen (e.g., chlorine, fluorine, or bromine) in step m-2), the reaction temperature is selected from -20 to 100°C, preferably 0 to 30°C.

[0362] In some embodiments, when E is an activated hydroxyl group in step m-2), the molar ratio of the compound of formula X-3-1 or its salt to the compound of formula X-1 or its salt is selected from 1:0.9 to 1:1.2.

[0363] In some embodiments, when E is an activated hydroxyl group in step m-2), the reaction solvent is selected from one of DMF, acetonitrile, tetrahydrofuran, and dichloromethane, or any combination thereof.

[0364] In some embodiments, when E is an activated hydroxyl group in step m-2), the compound of formula X-3-1 or a salt thereof reacts with the compound of formula X-1 or a salt thereof under basic conditions. The base is selected from organic or inorganic bases, preferably pyridine, triethylamine, N,N-diisopropylethylamine, and N-methylmorpholine.

[0365] In another embodiment, the present application provides a method for preparing an IV-2-2 compound or a salt thereof.

[0366] q-1) From the reaction of the compound of formula IV-2-2-1 or a salt thereof with the compound of formula IV-2-2-2 or a salt thereof, the compound of formula IV-2-2-3 or a salt thereof is obtained.

[0367] [ka]

[0368] q-2) By removing the protecting group from the compound of formula IV-2-2-3 or its salt, the compound of formula IV-2-2-4 or its salt is obtained.

[0369] [ka]

[0370] q-3) From the compound of formula IV-2-2-4 or a salt thereof, the compound of formula IV-2-2 or a salt thereof can be obtained.

[0371] [ka]

[0372] During the ceremony, L 3-2-1 and L 3-2-2 Each is independently selected from an amino acid residue or a short peptide consisting of 2-3 amino acid residues, and the above amino acid residues are natural amino acid residues, unnatural amino acid residues, or AA 1 Selected from the amino acid residues shown or their stereoisomers, E1 is a hydroxyl group, halogen, activated hydroxyl group, for example, hydroxyl group, chlorine, bromine,

[0373] [ka]

[0374] Selected from, PG4 is selected from amino protecting groups, and is selected from benzyloxycarbonyl group (Cbz), tert-butoxycarbonyl group (Boc), 9-fluorenylmethoxycarbonyl group (Fmoc), allyloxycarbonyl group (Alloc), trimethylsilylethoxycarbonyl group (Teoc), methoxycarbonyl group or ethoxycarbonyl group, preferably PG4 is selected from tert-butoxycarbonyl group (Boc), 9-fluorenylmethoxycarbonyl group (Fmoc), or allyloxycarbonyl group (Alloc), more preferably PG4 is tert-butoxycarbonyl group (Boc), and PG4 differs from PG2. The definitions of PG2 and E are as described in any one form of this application.

[0375] In some embodiments, in step q-1), a compound of formula IV-2-2-3 or a salt thereof is obtained by a condensation reaction between a compound of formula IV-2-2-1 or a salt thereof and a compound of formula IV-2-2-2 or a salt thereof.

[0376] In some embodiments, when E is an activated hydroxyl group in step q-1), the molar ratio of the compound of formula IV-2-2-1 or its salt to the compound of formula IV-2-2-2 or its salt is selected from 1:0.9 to 1:1.2.

[0377] In some embodiments, if E is an activated hydroxyl group in step q-1), the compound of formula IV-2-2-1 or a salt thereof reacts with the compound of formula IV-2-2-2 or a salt thereof under basic conditions. The base is selected from organic or inorganic bases, preferably sodium bicarbonate, potassium bicarbonate, sodium carbonate, potassium carbonate, sodium hydroxide, potassium hydroxide, and more preferably sodium bicarbonate.

[0378] In some embodiments, when E is an activated hydroxyl group in step q-1), the molar ratio of the compound of formula IV-2-2-1 or its salt to the base is selected from 1:1 to 1:8, preferably from 1:1 to 1:4.

[0379] In some embodiments, when E is an activated hydroxyl group in step q-1), the reaction solvent may be selected from one of ketones, chloroalkanes, ethers, esters, nitriles, amides, and water, or any combination thereof, preferably selected from one of acetone, tetrahydrofuran, ethyl acetate, dichloromethane, methyl tert-butyl ether, and water, or any combination thereof, and more preferably a mixed solvent of acetone, tetrahydrofuran, dichloromethane, and water.

[0380] In some embodiments, when E is an activated hydroxyl group in step q-1), the reaction temperature is selected from 0 to 50°C, preferably from 15 to 30°C.

[0381] In some embodiments, when E is a hydroxyl group in step q-1), the reaction proceeds under basic or neutral conditions under the action of a coupling agent, the coupling agent being a reagent well known to those skilled in the art, preferably DMTMM, HATU, HBTU, COMU, or N-ethynyl-N-methylmethanesulfonamide.

[0382] In some embodiments, when E is a hydroxyl group in step q-1), the molar ratio of the compound of formula IV-2-2-1 or its salt to the condensing agent is selected from 1:1 to 1:5, and is preferably 1:1 to 1:1.5.

[0383] In some embodiments, when E is a hydroxyl group in step q-1), the base is selected from organic or inorganic bases, preferably triethylamine, N,N-diisopropylethylamine, or N-methylmorpholine.

[0384] In some embodiments, when E is a hydroxyl group in step q-1), the molar ratio of the compound of formula IV-2-2-1 or its salt to the compound of formula IV-2-2-2 or its salt is selected from 1:0.9 to 1:1.2.

[0385] In some embodiments, when E is a hydroxyl group in step q-1), the reaction solvent is selected from one of DMF, acetonitrile, tetrahydrofuran, methanol, dichloromethane, and water, or any combination thereof, and is preferably DMF.

[0386] In some embodiments, when E is a hydroxyl group in step q-1), the reaction temperature is selected from -20 to 100°C, preferably 0 to 30°C.

[0387] In some embodiments, in step q-2), the compound of formula IV-2-2-3 or a salt thereof is deprotected to obtain the compound of formula IV-2-2-4 or a salt thereof.

[0388] In some embodiments, in step q-2), if PG4 is Boc, the compound of formula IV-2-2-3 or a salt thereof removes the protecting group under acidic conditions, the acid being a protic acid selected from hydrochloric acid, trifluoroacetic acid, hydrobromic acid, sulfuric acid, hydrogen chloride / dioxane, and hydrogen chloride / ethyl acetate, preferably hydrochloric acid, hydrogen chloride / dioxane, and hydrogen chloride / ethyl acetate, and more preferably hydrochloric acid.

[0389] In some embodiments, when PG4 is Boc in step q-2), the molar ratio of the compound of formula IV-2-2-3 or its salt to the acid is selected from 1:1 to 1:50, preferably 1:1 to 1:30, for example 1:1 to 1:20, and more preferably 1:1 to 1:5.

[0390] In some embodiments, when PG4 is Boc in step q-2), the reaction solvent is one of ether-based solvents, ester-based solvents, alkyl halide-based solvents, and water, or any combination thereof, preferably selected from one of tetrahydrofuran, 1,4-dioxane, and water, or any combination thereof, for example, 1,4-dioxane or tetrahydrofuran, preferably a mixed solvent of tetrahydrofuran and water.

[0391] In some embodiments, when PG4 is Boc in step q-2), the reaction temperature is 0 to 120°C, preferably 25 to 80°C.

[0392] In some embodiments, in step q-3), the compound of formula IV-2-2-4 or a salt thereof is subjected to a reductive amination reaction with an aldehyde under acidic or neutral conditions under the action of a reducing agent to obtain the compound of formula IV-2-2 or a salt thereof.

[0393] In some embodiments, in step q-3), the reducing agent is selected from sodium borohydride, potassium borohydride, sodium cyanoborohydride, and sodium triacetoxyborohydride, preferably sodium cyanoborohydride and / or sodium triacetoxyborohydride.

[0394] In some embodiments, in step q-3), the acid is selected from acetic acid, formic acid, propionic acid, trifluoroacetic acid, and hydrochloric acid, and is preferably acetic acid or hydrochloric acid.

[0395] In some embodiments, in step q-3), the molar ratio of the compound of formula IV-2-2-4 or its salt to the selected reducing agent is selected from 1:2 to 1:10, and preferably 1:2 to 1:4.

[0396] In some embodiments, in step q-3), the molar ratio of the compound of formula IV-2-2-4 or its salt to the aldehyde is selected from 1:1 to 1:10, preferably 1:3 to 1:5.

[0397] In some embodiments, in step q-3), the molar ratio of the compound of formula IV-2-2-4 or its salt to the acid is selected from 1:1 to 1:10, preferably 1:1 to 1:5.

[0398] In some embodiments, in step q-3), the reaction solvent is selected from one or any combination of alcohols, ethers, and water, preferably from one or any combination of methanol, ethanol, tetrahydrofuran, and water, and preferably a mixed solvent of tetrahydrofuran and water.

[0399] In some embodiments, in step q-3), the reaction temperature is -10 to 50°C, preferably 0 to 30°C.

[0400] intermediate In one embodiment, the present application provides a compound of formula IV-1 or a salt thereof,

[0401] [ka]

[0402] In the formula, L 3-1 The definitions of PG1 and R8 are as described in any one form of this application.

[0403] In another embodiment, the present application provides a compound of formula IV-2-1 or a salt thereof,

[0404] [ka]

[0405] In the formula, L 3-1The definition of R8 is as described in any one form of this application.

[0406] In another embodiment, the present application provides a compound of formula IV-2 or a salt thereof,

[0407] [ka]

[0408] In the formula, L 3 The definitions of PG2 and R8 are as described in any one form of this application.

[0409] In another embodiment, the present application provides a compound of formula X-3-1 or a salt thereof,

[0410] [ka]

[0411] In the formula, L 3 The definition of R8 is as described in any one form of this application.

[0412] In another embodiment, the present application provides a compound of formula X-3 or a salt thereof,

[0413] [ka]

[0414] In the formula, Lg, L 1 , L 2 , L 3 The definition of R8 is as described in any one form of this application.

[0415] In another embodiment, the present application provides the use of a compound or salt of formula IV-1 in the preparation of a compound or salt of formula IV-2, a compound or salt of formula IV-2-1, a compound or salt of formula X-3-1, a compound or salt of formula X-3, a compound or salt of formula II, or a compound or salt of formula I.

[0416] [ka]

[0417] In the formula, L 3-1 The definitions of PG1 and R8 are as described in any one form of this application.

[0418] In another embodiment, the present application provides the use of a compound or salt of formula IV-2-1 in the preparation of a compound or salt of formula IV-2, a compound or salt of formula X-3-1, a compound or salt of formula X-3, a compound or salt of formula II, or a compound or salt of formula I.

[0419] [ka]

[0420] In the formula, L 3-1 The definition of R8 is as described in any one form of this application.

[0421] In another embodiment, the present application provides the use of a compound or salt of formula IV-2 in the preparation of a compound or salt of formula X-3, a compound or salt of formula X-3-1, a compound or salt of formula II, or a compound or salt of formula I.

[0422] [ka]

[0423] In the formula, L 3The definitions of PG2 and R8 are as described in any one form of this application.

[0424] In another aspect, the present application provides the use of a compound or salt of formula X-3-1 in the preparation of a compound or salt of formula X-3, a compound or salt of formula II, or a compound or salt of formula I.

[0425] [ka]

[0426] In the formula, L 3 The definition of R8 is as described in any one form of this application.

[0427] In another aspect, the present application provides the use of a compound of formula X-3 or a salt thereof in the preparation of a compound of formula II or a salt thereof, a compound of formula I or a salt thereof,

[0428] [ka]

[0429] In the formula, Lg, L 1 , L 2 , L 3 The definition of R8 is as described in any one form of this application.

[0430] In another embodiment, the present application provides the use of a compound of formula I or a salt thereof in the preparation of an ADC drug.

[0431] [ka]

[0432] In the formula, Lg, L 1 , L 2 , L 3 The definitions of and D are as described in any one form of this application.

[0433] In another embodiment, the present application provides the use of a compound of formula II or a salt thereof in the preparation of an ADC drug.

[0434] [ka]

[0435] In the formula, Lg, L 1 , L 2 and L 3 The definition is as described in any one form of this application.

[0436] In some embodiments of this application, the compound of formula IV-1 or a salt thereof has the following structure:

[0437] [ka]

[0438] [ka]

[0439] Selected from.

[0440] In some embodiments of this application, the compound of formula IV-2-1 or a salt thereof has the following structure:

[0441] [ka]

[0442] Selected from.

[0443] In some embodiments of this application, the compound of formula IV-2 or a salt thereof has the following structure:

[0444] [ka]

[0445] [ka]

[0446] [ka]

[0447] [ka]

[0448] Selected from.

[0449] In some embodiments of this application, the compound of formula X-3-1 or a salt thereof has the following structure:

[0450] [ka]

[0451] [ka]

[0452] [ka]

[0453] Selected from.

[0454] In some embodiments of this application, the compound of formula X-3 or a salt thereof has the following structure:

[0455] [ka]

[0456] [ka]

[0457] [ka]

[0458] [ka]

[0459] [ka]

[0460] [ka]

[0461] [ka]

[0462] [ka]

[0463] Selected from.

[0464] In some embodiments of the present application, the compound represented by formula II above or a salt thereof has the following structure:

[0465] [ka]

[0466] Selected from.

[0467] Definitions and Terms Unless otherwise specified, the terms and phrases used herein have the meanings listed below. Unless otherwise defined, any particular term or phrase should not be considered uncertain or ambiguous, but should be interpreted according to the meaning generally understood by those skilled in the art. Where trade names appear herein, they are intended to indicate the corresponding product or its active ingredient.

[0468] In this application, singular words include their plural forms unless otherwise specified or indicated by the context. Accordingly, singular terms and references to “the said” and “the said” generally include their plural forms. The terms “include” and “inclusive” should be interpreted comprehensively, not exclusively.

[0469] In this application, unless otherwise specified or indicated by the context, the term “its salt” as used herein refers to the salt form of a compound (e.g., the compound of Formula 1). A salt form of a compound has one or more internal salt forms and / or contains another molecule. The counterion of a salt form of a compound is usually an organic or inorganic moiety that stabilizes the charge on the parent compound. A salt form of a compound has one or more charged atoms in its structure. If multiple charged atoms are part of the salt form, there are multiple counterions and / or multiple charged counterions. Thus, a salt form of a compound usually has one or more charged atoms corresponding to the unsalted form of the compound and one or more counterions. In some embodiments, the unsalted form of a compound contains at least one amino group or other basic moiety, so that in the presence of an acid, an acid addition salt having a basic moiety is obtained. In other embodiments, the unsalted form of a compound contains at least one carboxylic acid group or other acidic moiety, so that in the presence of a base, a carboxylate salt or other anionic moiety is obtained.

[0470] In this application, unless otherwise specified, the scientific and technical terms used herein have meanings that are generally understood by those skilled in the art. Furthermore, the laboratory procedures for cell culture, molecular genetics, nucleic acid chemistry, and immunology used herein are all common procedures widely used in their respective fields. Simultaneously, to better understand this application, definitions and interpretations of relevant terms are provided below.

[0471] As used herein, the term “stereoisomer” means an isomer formed by at least one chiral center. Compounds having one or more (e.g., one, two, three, or four) chiral centers can produce racemic mixtures, single enantiomers, diastereomer mixtures, and single diastereomers. Certain individual molecules may exist as geometric isomers (cis / trans). Similarly, the compounds of the present invention may exist as mixtures of two or more structurally different forms in rapid equilibrium (commonly called tautomers). Typical examples of tautomers include keto-enol tautomers, phenol-keto tautomers, nitroso-oxime tautomers, imine-enamine tautomers, and the like. It is understood that the scope of this application encompasses all such isomers or mixtures thereof in any proportion (e.g., 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%).

[0472] Carbon-carbon bonds in the compounds of the present invention may be depicted in this application using solid lines (—), solid wedge shapes, or dashed wedge shapes. Using solid lines to depict bonds to a chiral carbon atom is intended to indicate the presence of all possible stereoisomers at that carbon atom (e.g., specific enantiomers, racemic mixtures, etc.). Using solid or dashed wedge shapes to depict bonds to a chiral carbon atom is intended to indicate the presence of the indicated stereoisomers. In the case of racemic mixtures, solid and dashed wedge shapes are used to define relative stereochemistry rather than absolute stereochemistry. Unless otherwise specified, the compounds of the present invention are intended to exist in the form of stereoisomers (including cis and trans isomers, optical isomers (e.g., R and S enantiomers), diastereomers, geometric isomers, rotational isomers, conformational isomers, atropisomers, and mixtures thereof). The compounds of the present invention may exhibit one or more types of isomerism and consist of mixtures thereof (e.g., racemic mixtures and diastereomer pairs).

[0473] In this application, the term "bioactive molecule" means a substance that inhibits or prevents the function of cells and / or a substance that causes cell death or destruction, and in some embodiments of this application, the bioactive molecule in the complex is a molecule having antitumor bioactivity. For example, radioactive isotopes such as At211 and Lu, metallic platinum complexes, metallic gold complexes, metal complexes such as oxaliplatin, glycopeptide antibiotics such as bleomycin and pinyanmycin, topoisomerase 1 inhibitors, camptothecin, hydroxycamptothecin, 9-aminocamptothecin, SN-38, irinotecan, topotecan, berothecan, rubitecan, topoisomerase II inhibitors, actinomycin D, adriamycin, doxorubicin, duocalmycin, daunorubicin, mitoxantrone, podophyllotoxin, etoposide and other DNA topoisomerase inhibitors, methotrexate, 5-fluorouracil, cytarabine, gemcitabine, mercaptopurine, pentostatin, fludarabine, clarified The present invention relates to interfering DNA synthesis agents such as dribin and nelarabine, tubulin inhibitors, vinca alkaloids, drugs that act on structural proteins such as vincristine, vinblastine, paclitaxel, docetaxel, and cabazitaxel, tumor signaling pathway inhibitors such as serine / threonine kinase inhibitors, tyrosine kinase inhibitors, aspartate kinase inhibitors, or histidine kinase inhibitors, and further includes proteasome inhibitors, histone deacetylase inhibitors, tumor angiogenesis inhibitors, cyclin inhibitors, meitansine derivatives, calichemycin derivatives, auristatin derivatives, PBD derivatives, melphalan, mitomycin C, or active substances, enzymes and their fragments that inhibit tumor cell growth and promote apoptosis and necrosis of tumor cells.

[0474] In this application, the term "drug" means a substance that inhibits or prevents the function of cells and / or a substance that causes cell death or destruction.

[0475] In this application, the term "linker" refers to a fragment that links a fragment of a biologically active compound (drug molecule) to an antibody portion.

[0476] In this application, the term “antibody” takes its broadest interpretation, including complete monoclonal antibodies, polyclonal antibodies, and multispecific antibodies (e.g., bispecific antibodies) formed from at least two complete antibodies, as long as they possess the desired biological activity. In this application, “antibody” and “immunoglobulin” can be used interchangeably.

[0477] In this application, the term "monoclonal antibody" refers to an antibody derived from a basically homogeneous population of antibodies, that is, the individual antibodies constituting the population are completely identical except for the possibility of small amounts of natural mutations. Monoclonal antibodies have high specificity for one determinant (epitope) of an antigen, while polyclonal antibodies, on the other hand, contain different antibodies for different determinants (epitopes). An advantage of monoclonal antibodies, in addition to their specificity, is that they are not contaminated by other antibodies during synthesis. Here, the modifier "monoclonal" means that the antibody is characterized by being derived from a basically homogeneous population of antibodies, but it should not be understood as requiring that it be produced by a specific method.

[0478] In this Application, unless otherwise explicitly indicated, the explanatory phrases "each of the ... is selected independently" and "... are each selected independently," which are used throughout this Application, are interchangeable and should both be understood in a broad sense, meaning that specific choices expressed between the same or different symbols do not affect each other under different conditions, or that specific choices expressed between the same or different symbols do not affect each other under the same conditions.

[0479] In this application, AA 1 Structure of amino acid residues shown

[0480] [ka]

[0481] In this case, if r is 0, AA 1 The structure of the amino acid residue shown is

[0482] [ka]

[0483] This can be understood by those skilled in the art. AA 1 Structure of amino acid residues shown

[0484] [ka]

[0485] In R a and R b These, together with the carbon atoms linked to them, form a 4-10 membered heterocycle, and the above 4-10 membered heterocycle can optionally have one or more R 0 This is replaced by, where, "the above 4- to 10-membered complex rings are optionally one or more R 0 The term "substituted by" means that the above 4- to 10-membered hetero rings do not necessarily have to be substituted, and one or more R 0 This means that it may be replaced by the above multiple R 0 In each R 0 The definitions may be the same or different. Other similar definitions can be understood by referring to the above.

[0486] In each part of this specification, substituents of the compounds of the Application are disclosed by type or range of groups. In particular, the Application includes each independent secondary combination of each member of these types and ranges of groups. For example, the term “C1-6 alkyl groups” refers to the methyl group, ethyl group, C3 alkyl group, C4 alkyl group, C5 alkyl group and C6 alkyl group, which are disclosed in particular independently.

[0487] The terms “including,” “incorporating,” “possessing,” “containing,” or “concerning,” and other variations thereof herein, are inclusive or open and do not exclude other elements or method steps not enumerated.

[0488] In this application, “parent ring” is

[0489] [ka]

[0490] That is the case.

[0491] In this application, the term "C1-30 alkyl group" refers to a linear or branched alkyl group containing 1 to 30 carbon atoms, including "C1-6 alkyl group," and the term "C1-6 alkyl group" refers to a linear or branched alkyl group containing 1 to 6 carbon atoms, including "C1-3 alkyl group" or "C1-4 alkyl group," methyl group, ethyl group, etc. Specific examples include, but are not limited to, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, and hexyl group.

[0492] In this application, the term "C2-6 alkenyl group" refers to a linear, branched, or cyclic alkenyl group having 2 to 6 carbon atoms and containing at least one double bond, including "C2-4 alkenyl group," etc. Examples include, but are not limited to, vinyl group, 1-propenyl group, 2-propenyl group, 1-butenyl group, 2-butenyl group, 1,3-butadienyl group, 1-pentenyl group, 2-pentenyl group, 3-pentenyl group, 1,3-pentadienyl group, 1,4-pentadienyl group, 1-hexenyl group, 2-hexenyl group, 3-hexenyl group, 1,4-hexadienyl group, cyclopentenyl group, 1,3-cyclopentadienyl group, cyclohexenyl group, and 1,4-cyclohexadienyl group.

[0493] In this application, the term "C2-6 alkynyl group" refers to a linear or branched alkynyl group having 2 to 6 carbon atoms and containing at least one triple bond, including "C2-4 alkynyl group," etc. Examples include, but are not limited to, ethynyl group, propynyl group, 2-butynyl group, 2-pentynyl group, 3-pentynyl group, 4-methyl-2-pentynyl group, 2-hexynyl group, 3-hexynyl group, and 5-methyl-2-hexynyl group.

[0494] In this application, the term "halogen" includes fluorine, chlorine, bromine, and iodine.

[0495] In this application, the term "C3-7 cycloalkyl group" refers to a saturated cyclic alkyl group containing 3 to 7 carbon atoms, and the term "C3-6 cycloalkyl group" refers to a saturated cyclic alkyl group containing 3 to 6 carbon atoms. Optionally, carbon atoms in the cyclic structure may be substituted with oxo groups. Examples include cyclopropane (i.e., cyclopropyl), cyclobutane (i.e., cyclobutyl), cyclopentane (i.e., cyclopentyl), and cyclohexyl groups.

[0496] In this application, the term "C1-6 alkoxy group" means the alkyl group defined above, which is linked to the parent molecule via an oxygen atom, including "C1-3 alkoxy group" or "C1-4 alkoxy group". Specific examples include, but are not limited to, methoxy group, ethoxy group, propoxy group, isopropoxy group, n-propoxy group, isopropoxy group, n-butoxy group, isobutoxy group, tert-butoxy group, pentyloxy group, and hexyloxy group.

[0497] In this application, the term "C1-6 haloalkyl group" refers to the alkyl group defined above, which is linked to the parent molecule via a halogen, including, for example, "C1-3 haloalkyl groups" or "C1-4 haloalkyl groups." Specific examples include, but are not limited to, chloromethyl groups, fluoroethyl groups, and bromopropyl groups.

[0498] In this application, the term "3-20 membered heterocyclic group" refers to a cyclic group containing 3 to 20 ring atoms (of which at least one ring atom is a heteroatom such as a nitrogen atom, oxygen atom, or sulfur atom). The term "4-10 membered heterocyclic group" refers to a cyclic group containing 4 to 10 ring atoms (of which at least one ring atom is a heteroatom such as a nitrogen atom, oxygen atom, or sulfur atom). The term "3-6 membered heterocyclic group" refers to a cyclic group containing 3 to 6 ring atoms (of which at least one ring atom is a heteroatom such as a nitrogen atom, oxygen atom, or sulfur atom). The term "5-6 membered heterocyclic group" refers to a cyclic group containing 5 to 6 ring atoms (of which at least one ring atom is a heteroatom such as a nitrogen atom, oxygen atom, or sulfur atom). Optionally, the ring atoms in the cyclic structure (e.g., carbon atoms, nitrogen atoms, or sulfur atoms) may be substituted with oxo groups. "4- to 8-membered heterocyclic groups" include, for example, "4- to 8-membered nitrogen-containing heterocyclic groups," "4- to 8-membered oxygen-containing heterocyclic groups," "4- to 7-membered heterocyclic groups," "4- to 7-membered oxygen-containing heterocyclic groups," "4- to 7-membered heterocyclic groups," "4- to 6-membered heterocyclic groups," "4- to 6-membered heterocyclic groups," "5- to 7-membered heterocyclic groups," and "5- to 6-membered nitrogen-containing heterocyclic groups." This includes, but is not limited to, oxetanyl groups, pyrrolidinyl groups, tetrahydrofuranyl groups, piperidinyl groups, piperazinyl groups, tetrahydropyranyl groups, homopiperazinyl groups, etc.

[0499] In this application, the term "4- to 10-membered heterocycle" refers to a ring containing 4 to 10 ring atoms (of which at least one ring atom is a heteroatom such as a nitrogen atom, an oxygen atom, or a sulfur atom). The term "3- to 6-membered heterocycle" refers to a ring containing 3 to 6 ring atoms (of which at least one ring atom is a heteroatom such as a nitrogen atom, an oxygen atom, or a sulfur atom). The term "5- to 6-membered heterocycle" refers to a ring containing 5 to 6 ring atoms (of which at least one ring atom is a heteroatom such as a nitrogen atom, an oxygen atom, or a sulfur atom). Optionally, the ring atoms in the cyclic structure (e.g., carbon atoms, nitrogen atoms, or sulfur atoms) may be substituted with oxo groups. Examples include, but are not limited to, rings such as pyrrolidine, tetrahydrofuran, piperidine, piperazine, and tetrahydropyran.

[0500] In this application, the term "aryl group" means an aromatic monocyclic or polycyclic hydrocarbon group, such as a 6-10 membered aryl group or a 5-8 membered aryl group. Specific examples include, but are not limited to, phenyl, naphthyl, anthracenyl, and phenanthryl groups. The above-mentioned "6-10 membered aryl group" means an aryl group containing 6-10 ring atoms. The above-mentioned "C6-10 aryl group" means an aryl group containing 6-10 carbon atoms.

[0501] In this application, the term “heteroaryl group” means an aromatic cyclic group in which at least one ring atom is a heteroatom such as a nitrogen atom, an oxygen atom, or a sulfur atom. Optionally, the ring atoms in the cyclic structure (e.g., carbon atoms, nitrogen atoms, or sulfur atoms) may be substituted with an oxo group. Specific examples include, but are not limited to, furyl, thienyl, pyrrolyl, thiazolyl, isothiazolyl, thiadiazolyl, oxazolyl, isoxazolyl, oxadiazolyl, imidazolyl, pyrazolyl, 1,2,3-triazolyl, 1,2,4-triazolyl, 1,2,3-oxadiazolyl, 1,2,4-oxadiazolyl, and 1,2,5-oxadi These include azolyl group, 1,3,4-oxadiazolyl group, pyridyl group, 2-pyridonyl group, 4-pyridonyl group, pyrimidinyl group, 1,4-dioxacyclohexadienyl group, 2H-1,2-oxazinyl group, 4H-1,2-oxazinyl group, 6H-1,2-oxazinyl group, 4H-1,3-oxazinyl group, 6H-1,3-oxazinyl group, 4H-1,4-oxazinyl group, pyridadinyl group, pyrazinyl group, 1,2,3-triazinyl group, 1,3,5-triazinyl group, 1,2,4,5-tetradinyl group, azacycloheptatrieyl group, 1,3-diazacycloheptatrieyl group, azacyclooctatetraenyl group, and others.

[0502] In this application, the bonds in structural formulas represented by the wavy lines "~~" mean that the structure represents a cis or trans isomer, or a mixture of cis and trans isomers in any proportion.

[0503] In this application, the term "room temperature" means 25±5℃.

[0504] In this application, the above-mentioned protecting groups and methods for linking or removing them can be realized using conventional methods of the art, which may be one-step or multi-step reactions, and can be achieved, for example, by referring to, but not limited to, Greene's Protective Groups in Organic Synthesis - 4th Edition by Wiley Press or Protective Groups Chemistry by Chemical Industry Press.

[0505] In this application, the term "amino protecting group" means a group that protects an amino group in a compound, and can be selected from amino protecting groups known in the art. The medium for the protection reaction described in this application is preferably selected from aprotic solvents, and is preferably dichloromethane. The upper protecting group reaction that protects the amino group can be carried out using conventional reaction conditions well known to those skilled in the art. The reaction that removes the protecting group from the amino group can be carried out using conventional reaction conditions well known to those skilled in the art. Preferably, the amino protecting group used in the present invention is selected from unsubstituted or substituted alkoxycarbonyl protecting groups, such as benzyloxycarbonyl group, tert-butoxycarbonyl group, fluorenylmethoxycarbonyl group, allyloxycarbonyl group, trimethylsilylethoxycarbonyl group, methoxycarbonyl group, or ethoxycarbonyl group.

[0506] In this application, the term "hydroxy protecting group" means a group that protects a hydroxyl group in a compound, and can be selected from hydroxy protecting groups known in the art. The upper protecting group reaction that protects a hydroxyl group can be carried out using conventional reaction conditions well known to those skilled in the art. The reaction that removes a protecting group from a hydroxyl group can be carried out using conventional reaction conditions well known to those skilled in the art. Preferably, the hydroxy protecting group used in the present invention is selected from unsubstituted or substituted benzyl groups, such as benzyl group, p-nitrobenzyl group, and p-methoxybenzyl group.

[0507] In this application, where the term "approximately" is used with a number or range of numbers, it refers to adjusting the number or range of numbers by extending the boundary of the number upward and / or downward. For example, the term "approximately" is intended to modify a number by 20% or less, more preferably 10% or less, above or below its value.

[0508] In this application, if a compound is given both a name and a structural formula at the same time, and the two do not match, the structure of the compound shall prevail unless the context indicates that the name is correct but the structure is inaccurate.

[0509] In this disclosure, compounds may exist in specific geometric or stereoisomeric forms. This application assumes that all compounds, including cis and trans isomers, (-)- and (+)-enantiomers, (R)- and (S)-enantiomers, diastereomers, (D)-isomers, (L)-isomers, and other mixtures such as racemic mixtures and mixtures with an enantiomer or diastereomer excess, are within the scope of this disclosure. Substituents such as alkyl groups may have other chiral carbon atoms. All of these isomers and mixtures thereof are within the scope of the present invention.

[0510] All reagents and raw materials used in this invention are commercially available.

[0511] The positive advancements of this invention are as follows: This disclosure, based on numerous studies, describes an azaacetal structure suitable for industrial production.

[0512] [ka]

[0513] We have developed a synthetic method for preparing drug linker complexes containing [the specified substance]. This preparation method has the following advantages: 1) Wide substrate applicability. It exhibits excellent applicability to molecules containing groups that are unstable in the presence of Pb(OAc)4 (e.g., amino groups, substituted amino groups). It also exhibits excellent applicability to substrates that are unstable under basic conditions (e.g., camptothecin compounds).

[0514] 2) The isolation and purification of the compound is easy to perform, yields high results (high yield of 95% in key steps), and is suitable for industrial production.

[0515] 3) The reaction conditions are mild, carried out at atmospheric pressure, and the reaction temperature is easy to control.

[0516] 4) These raw materials are readily available and inexpensive.

[0517] 5) Using A1.9 (i.e., compound III of the present application) as a starting material, the target molecule can be obtained through only a single reaction step, and the reaction steps involving highly active molecules (the original pathway has three steps) are significantly reduced.

[0518] 6) The reaction yield is greatly improved. Based on A1.9 (i.e., compound III of this application), the total yield of the original route is less than 5%, while the total yield of the new route is greater than 50%.

[0519] 7) All intermediates have simple purification methods and are easy to scale up.

[0520] 8) All intermediates are highly stable and do not form polymers.

[0521] 9) The entire process is environmentally friendly, does not use Class 1 or Class 2A metals, and does not have the effect of residual elemental impurities on the reaction and final product (for example, in conventional techniques, if Pb(OAc)4 is used, Pb remains, causing poisoning of the metal catalyst for subsequent removal of amino protecting groups by metal catalytic hydrogenation, resulting in low reaction yield).

[0522] 10) The overall process (especially when using Cbz protecting groups, which is more suitable for liquid-phase reactions) has better stability of the corresponding intermediates, the reaction conditions are more environmentally friendly, and the removal of toluene as a byproduct is easier. [Modes for carrying out the invention]

[0523] Sequence information The sequence information relating to this application is described in the table below.

[0524] [Table 1]

[0525] All features, or steps in any method or process disclosed herein, can be combined in any way except for features and / or steps that are mutually exclusive.

[0526] Any of the features disclosed herein may be replaced by other equivalent or similar features unless otherwise specified. That is, each feature is merely an example of a set of equivalent or similar features unless otherwise specified.

[0527] The operating conditions used in the examples can be further adjusted according to specific requirements, and operating conditions not noted are generally those used in typical experiments.

[0528] The chemical reagents used in the following examples are all commercially available chemical reagents.

[0529] In the conventional synthesis method, examples, and intermediate synthesis examples, the meaning of each abbreviation or English term is shown in the table below:

[0530] [Table 2]

[0531] In exemplary embodiments of the present invention, drug linker complex IIa is synthesized using the following pathway:

[0532] Route (1)

[0533] [ka]

[0534] Route (2)

[0535] [ka]

[0536] Route (3)

[0537] [ka]

[0538] Route (4)

[0539] [ka]

[0540] Route (5)

[0541] [ka]

[0542] Preparative HPLC chromatography conditions 1 Column: C18 preparative column (100 mm × 250 mm, 10 μm), Wavelength: 214 nm, Flow rate: 250 mL / min, Mobile phase A: 0.1% formic acid aqueous solution, Mobile phase B: Acetonitrile Gradient table:

[0543] [Table 3]

[0544] Preparative HPLC chromatography conditions 2 Step 1: Purification

[0545] [Table 4]

[0546] Step 2: Desalting and concentration

[0547] [Table 5]

[0548] HPLC chromatography conditions (Method 1)

[0549] [Table 6]

[0550] Chiral HPLC chromatography conditions

[0551] [Table 7]

[0552] Synthesis of drug linker complex IIa Example 1: Synthesis of Intermediate III Step 1: Preparation of 4-(6-nitrobenzo[d][1,3]dioxolan-5-yl)buta-3-in-1-ol(III-2)

[0553] [ka]

[0554] Compound III-1 (100 g, 408 mmol) and 3-buty-1-ol (11.4 g, 163 mmol) were dissolved in NMP (300 mL), triethylamine (102 g, 1.02 mol, 141 mL) was added, and the mixture was protected with nitrogen gas. CuI (3.88 g, 20.4 mmol) and Pd(PPh3)2Cl2 (2.9 g, 4.1 mmol) were then added in sequence, and the reaction was carried out at 50°C for 0.5 hours. 3-buty-1-ol (22.8 g, 326 mmol) was added dropwise, and after the addition was complete, the reaction was continued at 50°C for 4 hours. The reaction mixture was cooled to room temperature, water (4.5 L) containing aqueous ammonia (3.26 mol) was added, and the solid was precipitated. The mixture was stirred for 0.5 hours. The mixture was filtered by suction, and the filter cake was added to water (4.5 L) and stirred for 0.5 hours. The solution was filtered by suction, and the filtered cake was added to water (4.5 L) and stirred for 0.5 hours. The solution was filtered by suction, and the filtered cake was dried to obtain 85.0 g of the target product III-2, with a yield of 88%. LCMS (ESI) [M+H] + = 236.0 1 H NMR (400 MHz, DMSO-d6) δ 7.66 (s, 1H), 7.18 (s, 1H), 6.25 (s, 2H), 4.91 (t, J = 5.6 Hz, 1H), 3.59 (dd, J = 12.6, 6.7 Hz, 2H), 2.59 (t, J = 6.9 Hz, 2H). Step 2: Preparation of 1-(6-aminobenzo[d][1,3]dioxolan-5-yl)-4-hydroxybutan-1-one(III-3)

[0555] [ka]

[0556] Compound III-2 (8.42 g, 35.79 mmol) was dissolved in EtOH / H2O (v:v=9:1, 152 mL), Sn (8.46 g, 71.58 mmol) and Na2S·9H2O (2.58 g, 10.74 mmol) were added, and concentrated hydrochloric acid (30 mL, 358 mmol) was added. The mixture was stirred at 78°C for 1 hour. The reaction mixture was filtered by suction through diatomaceous earth while still hot, and the filtrate was concentrated to obtain the crude product. Ethyl acetate (20 mL) was added to form a slurry, which was filtered by suction. The filter cake was washed twice with ethyl acetate (5 mL) to obtain the crude product. Water (50 mL) was added to the crude product, and saturated sodium bicarbonate solution was added dropwise until the pH value reached 8.0. The mixture was stirred at room temperature for 1 hour. The mixture was filtered by suction, and the filtrate was extracted with ethyl acetate (50 mL x 2). After concentration, a solid was obtained. The obtained solid was combined with the filtration cake, dried, and 3.6 g of the target product III-3 was obtained. LCMS (ESI) [M-18+H] + =206.2 1 H NMR (400 MHz, CD3OD) δ 7.18 (s, 1H), 6.24 (s, 1H), 5.87 (s, 2H), 3.62 (t, J = 6.7 Hz, 2H), 2.95-2.84 (m, 2H), 1.95-1.82 (m, 2H). Step 3: Preparation of (S)-7-ethyl-7-hydroxy-14-(3-hydroxypropyl)-10,13-dihydro-11H-[1,3]dioxolo[4,5-g]pyrano[3',4':6,7]indolidino[1,2-b]quinoline-8,11(7H)-dione(III)

[0557] [ka]

[0558] Compounds III-3 (41.80 g, 0.19 mol), III-4 (110.00 g, 0.42 mol), and p-toluenesulfonic acid monohydrate (31.90 g, 0.17 mol) were added to a three-necked flask. 550 mL of NMP was weighed and added to the flask, and the mixture was protected with nitrogen gas. The mixture was heated and stirred at 110°C, and III-3 (31.35 g, 0.14 mol) was added to the reaction system three times at 0.5-hour intervals. After the additions were complete, stirring was continued for 1 hour. Isopropyl alcohol (110 mL) was added to the reaction mixture, followed by the dropwise addition of water (1.32 L). The mixture was cooled to 5°C and stirred for 1.0 hour. The mixture was filtered by suction, the filter cake was washed with water, and the mixture was slurryed with water (13.75 L) for 2 hours. The mixture was filtered by suction, and the filter cake was washed again with water. The filtered cake was added to the reaction flask, and DMF (165 mL) and methanol (1.32 L) were added in sequence. The mixture was stirred at 25°C for 12 hours, filtered by suction, washed with methanol, and vacuum-dried at 50°C for 48 hours to obtain 184.0 g of the target product III. LCMS (ESI) [M+H] + = 451.4 1 H NMR (400 MHz, DMSO-d6) δ 7.59 (s, 1H), 7.49 (s, 1H), 7.25 (s, 1H), 6.49 (s, 1H), 6.30 (s, 2H), 5.54 - 5.36 (m, 2H), 5.19 (s, 2H), 4.68 (t, J = 5.0 Hz, 1H), 3.51 (q, J = 5.6 Hz, 2H), 3.14 (t, J = 7.6 Hz, 2H), 1.99-1.73 (m, 4H), 0.92 (t, J = 7.3 Hz, 3H).

[0559] Example 2: Synthesis of intermediate IV-2-2 1. Synthesis of intermediate IV-2-2-A Step 1: N 2 -((9H-fluoren-9-yl)methoxy)carbonyl)-L-valine)-N 6 Preparation of -(tert-butoxycarbonyl)-L-lysine (IV-2-2-A-3)

[0560] [ka]

[0561] Compounds IV-2-2-A-1 (100 g, 0.229 mol) and IV-2-2-A-2 (56.4 g, 0.229 mol) were placed in a reaction flask, and acetone / water (1 L, v:v=1:1) was added under stirring conditions, followed by the addition of NaHCO3 (76.95 g, 0.916 mol). The mixture was stirred overnight at room temperature. Insoluble matter was removed by filtration, the filtrate was concentrated, hydrochloric acid (4N) was added to the concentrate to adjust the pH to 5, and the solution was extracted with ethyl acetate (0.75 L x 2). The organic phases were combined and washed with saturated brine (300 mL x 2), dried over anhydrous sodium sulfate, and the filtrate was concentrated under reduced pressure to obtain 117 g of the target compound IV-2-2-A-3, with a yield of 90%. LCMS (ESI) [M+H] + = 568.3 1 H NMR (400 MHz, DMSO-d6) δ 7.91 (d, J = 7.5 Hz, 2H), 7.82-7.73 (m, 2H), 7.64 (d, J = 6.9 Hz, 1H), 7.58 (d, J = 9.1 Hz, 1H), 7.44 (t, J = 7.4 Hz, 2H), 7.40-7.31 (m, 2H), 6.68 (brs, 1H), 4.38-4.21 (m, 3H), 3.99-3.91 (m, 1H), 3.87 (dd, J = 8.8, 6.8 Hz, 1H), 2.92-2.80 (m, 2H), 2.17-2.01 (m, 1H), 1.70-1.67 (m, 1H), 1.64-1.52 (m, 1H), 1.42-1.16 (m, 13H), 0.93-0.83 (m, 6H). Step 2: Preparation of (((9H-fluoren-9-yl)methoxy)carbonyl)-L-valine-L-lysine hydrochloride (IV-2-2-A-4)

[0562] [ka]

[0563] Compound IV-2-2-A-3 (117 g, 206.2 mmol) was mixed with dioxane (1.5 L) and stirred for 10 minutes. Then, HCl / dioxane (0.75 L, 4 mol / L) was added and the mixture was stirred at room temperature for 12 hours. Methyl tert-butyl ether (2 L) was added to the reaction mixture and stirred for 30 minutes. The mixture was filtered, and the filter cake was dried to obtain 94 g of the target compound IV-2-2-A-4, with a yield of 91%. LCMS (ESI) [M+H] + = 468.3 1 H NMR (400 MHz, DMSO-d6) δ 8.24 (d, J = 7.3 Hz, 1H), 8.07 (brs, 3H), 7.90 (d, J = 7.5 Hz, 2H), 7.77 (dd, J = 7.1, 3.4 Hz, 2H), 7.47-7.37 (m, 3H), 7.34 (td, J = 7.4, 1.7 Hz, 2H), 4.34-4.17 (m, 4H), 3.96 (dd, J = 8.6, 7.4 Hz, 1H), 2.83-2.65 (m, 2H), 2.04 (dd, J = 13.5, 6.7 Hz, 1H), 1.82-1.52 (m, 4H), 1.51-1.30 (m, 2H), 0.96-0.84 (m, 6H). Step 3 N 2 ((((9H-fluoren-9-yl)methoxy)carbonyl)-L-valine)-N 6 , N 6 Preparation of -dipropyl-L-lysine (IV-2-2-A)

[0564] [ka]

[0565] Compound IV-2-2-A-4 (55.0 g, 109.1 mmol) and acetic acid (10 mL) were dissolved in methanol (500 mL) solution. Under an ice bath, n-propionaldehyde (25.35 g, 436.4 mmol) was added to the reaction mixture and the reaction was carried out at room temperature with stirring for 30 minutes. Under an ice bath, sodium cyanoborohydride (27.43 g, 436.4 mmol) was added to the reaction mixture and the reaction was carried out at room temperature with stirring for 1 hour. LCMS showed that the starting materials had not reacted completely. n-propionaldehyde (12.67 g, 218.2 mmol) and sodium cyanoborohydride (13.72 g, 218.2 mmol) were added and the reaction was continued for 0.5 hours. The reaction mixture was filtered, the filtrate was concentrated, purified water (300 mL) was added to the concentrate, and extraction was performed using DCM (300 mL x 2). The organic phase was washed with saturated brine, dried over anhydrous Na2SO4, and then concentrated to obtain the crude product. The crude product was purified by column chromatography (elutes: MeOH and DCM) to obtain 39 g of compound IV-2-2-A, with a yield of 65%. LCMS (ESI) [M+H] + = 552.3 1 H NMR (400 MHz, DMSO-d6) δ 7.95-7.85 (m, 3H), 7.76 (t, J = 7.3 Hz, 2H), 7.51-7.40 (m, 3H), 7.35 (t, J = 7.4 Hz, 2H), 4.34-4.22 (m, 3H), 4.13 (dd, J = 12.6, 7.2 Hz, 1H), 3.91 (dd, J = 8.8, 7.1 Hz, 1H), 2.52 - 2.41 (m, 6H), 2.03 (dt, J = 13.5, 6.7 Hz, 1H), 1.79-1.67 (m, 1H), 1.66-1.56 (m, 1H), 1.42-1.36 (m, 6H), 1.36-1.21 (m, 2H), 0.90 (t, J = 6.9 Hz, 6H), 0.82 (t, J = 6.9 Hz, 6H).

[0566] II. Synthesis of intermediate IV-2-2-B Step 1: Synthesis of N-((benzyloxy)carbonyl)-L-valine)-N-(tert-butoxycarbonyl)-L-lysine (IV-2-2-B-3)

[0567] [ka]

[0568] Method 1: Compounds IV-2-2-B-1 (50.0 g, 143.53 mmol) and IV-2-2-A-2 (35.35 g, 143.53 mmol) were weighed, dissolved in acetone (250 mL) and water (250 mL), and then NaHCO3 (48.23 g, 574.12 mmol) was added. The mixture was stirred overnight at room temperature. The solution was filtered by suction, and the filtrate was concentrated until the acetone was gone. The pH was then adjusted to 5 with hydrochloric acid (4 mol / L) to precipitate a large amount of solid. The solution was filtered by suction, the filter cake was rinsed with water (100 mL), and the resulting filter cake was further slurryed in DCM (700 mL) for 30 minutes. After filtering by suction, the filter cake was dried at 50°C to obtain 65.0 g of the target product IV-2-2-B-3, with a yield of 94.5%.

[0569] Method 2: Compound IV-2-2-A-2 (35.35 g, 143.53 mmol) was weighed and added to a solution of NaHCO3 (24.12 g, 287.06 mmol) in 250 mL of water. A solution of IV-2-2-B-1 (50.0 g, 143.53 mmol) in 250 mL of DCM was then added dropwise under ice water. After the addition was complete, the reaction system was stirred at room temperature for 10 hours. The reaction system was adjusted to pH=5 with hydrochloric acid (4 mol / L), stirred for 1 hour, and then filtered by suction. The filtered cake was dried to obtain 65.0 g of the target product IV-2-2-B-3, with a yield of 94.5%.

[0570] Method 3: Compound IV-2-2-A-2 (35.35 g, 143.53 mmol) was weighed and added to a solution of NaHCO3 (24.12 g, 287.06 mmol) in water (250 mL). A solution of IV-2-2-B-1 (50.0 g, 143.53 mmol) in THF (250 mL) was added dropwise under an ice bath. After the addition was complete, the reaction system was stirred at room temperature for 4 hours. The reaction mixture was concentrated to remove the organic solvent, then the pH was adjusted to 5 with hydrochloric acid (4 mol / L). After stirring for 1 hour, the mixture was filtered by suction. The filtered cake was slurried in DCM (700 mL) for 30 minutes, filtered by suction, and the filtered cake was dried to obtain 65.0 g of the target product IV-2-2-B-3, with a yield of 94.5%. LCMS(ESI)[M+H-Boc] + =380.31 1 H NMR (400 MHz, DMSO-d6) δ 8.07 (d, J = 8.0 Hz, 1H), 7.36 - 7.30 (m, 5H), 7.23 (d, J = 8.0 Hz, 1H), 6.74 (t, J = 8 Hz, 1H), 5.04 (s, 2H), 4.18-4.12 (m, 1H), 3.94-3.90 (m, 1H), 2.91-2.87 (m, 2H), 1.97-1.85 (m, 1H), 1.74 - 1.64 (m, 1H), 1.62 - 1.52 (m, 1H), 1.42 - 1.23 (m, 13H), 0.90 - 0.83 (m, 6H). Step 2: Synthesis of ((benzyloxy)carbonyl)-L-valine-L-lysine hydrochloride (IV-2-2-B-4)

[0571] [ka]

[0572] Method 1: Compound IV-2-2-B-3 (65.0 g, 135.54 mmol) was mixed with dioxane (520 mL) and stirred for 10 minutes. Then, 260 mL of HCl (4 mol / L in Dioxane) was added, and the mixture was stirred overnight at room temperature. MTBE (1300 mL) was added to the reaction mixture and stirred for 30 minutes. The mixture was then filtered, and the filter cake was dried to obtain 52 g of the target compound IV-2-2-B-4, with a yield of 93%.

[0573] Method 2: Compound IV-2-2-B-3 (50.0 g, 104.26 mmol) was weighed and added to tetrahydrofuran (20 mL), then concentrated hydrochloric acid (17.2 mL, 206.40 mmol) was added, and the reaction was carried out while heating at 60°C for 1 hour. The reaction solution was then cooled to room temperature and used directly in the next reaction. LCMS(ESI)[M+H] + =380.42 1 H NMR (400 MHz, DMSO-d6) δ 12.59 (s, 1H), 8.19 (d, J = 8.0 Hz, 1H), 7.96 (s, 3H), 7.40 - 7.34 (m, 5H), 8.27 (d, J = 8.0 Hz, 1H), 5.06 (s, 2H), 4.22 - 4.17 (m, 1H), 3.96 - 3.92 (m, 1H), 2.80 - 2.77 (m, 2H), 2.04-2.00 (m, 1H), 1.63 - 1.57 (m, 4H), 1.41 - 1.39 (m, 2H), 0.93 - 0.87 (m, 6H).

[0574] Step 3: Synthesis of N-((benzyloxy)carbonyl)-L-propionyl)-N,N-dipropyl-L-lysine (IV-2-2-B)

[0575] [ka]

[0576] Method 1: Compound IV-2-2-B-4 (52 g, 125.03 mmol) obtained in Method 1 of Step 2 was dissolved in methanol (520 mL), stirred, and then sodium borohydride cyanohydride (15.71 g, 250.06 mmol) was added to the reaction mixture, followed by the addition of n-propionaldehyde (14.52 g, 250.06 mmol), and the mixture was reacted for 1 hour. Then n-propanal (14.52 g, 250.06 mmol) was added and the mixture was reacted for 1 hour. Water (45 mL, 2.5 mol) was added to the reaction mixture and stirred for 10 minutes, then concentrated. THF (200 mL) was added to the concentrate and concentrated, and the water was removed. The above procedure was repeated once. DCM (250 mL) was added to the residue to dissolve it, insoluble matter was filtered off, the filtrate was concentrated, and the resulting crude product of the target compound IV-2-2-B was used directly in the next reaction, and the yield was calculated based on 100%.

[0577] Method 2: To the solution obtained in Method 2 of Step 2, THF (300 mL) was added, sodium borohydride cyanohydride (19.7 g, 312.78 mmol) was added under an ice bath, and then n-propionaldehyde (24.3 g, 417.04 mmol) was added. The mixture was heated to room temperature and reacted with stirring for 1 hour. Hydrochloric acid was added to adjust the pH to 4-5, and the mixture was stirred for 30 minutes. The reaction system was concentrated to remove THF, water (200 mL) and DCM (200 mL) were added, and the organic phase was collected. 60.0 g of anhydrous sodium sulfate was added to the aqueous phase, and it was extracted again with DCM (100 mL). The organic phases were combined, dried over anhydrous sodium sulfate, insoluble matter was filtered off, and the mixture was concentrated to obtain 38.0 g of the target compound, with a 2-step yield of 78.6%. LCMS(ESI)[M+H] + =464.44 1H NMR (400 MHz, DMSO-d6) δ 7.93 (d, J = 8.0 Hz, 1H), 7.35 - 7.26 (m, 6H), 5.03 (s, 2H), 4.15 - 4.10 (m, 1H), 3.91 - 3.87 (m, 1H), 2.76 - 2.58 (m, 6H), 2.00 - 1.96 (m, 1H), 1.82 - 1.19 (m, 10H), 0.89 - 0.84(m, 12H).

[0578] Example 3: Synthesis of Intermediate IV-1 1. Synthesis of IV-1-A Route 1:

[0579] [ka]

[0580] Method 1: Compound IV-1-A-1 (5 g, 17.84 mmol) was added to trifluoroethanol (30 mL), protected with argon gas, and stirred at 40°C to dissolve. Then, HCl DMF solution (2.1 mL, 0.4 mol / L) was added, and the mixture was stirred at 40°C for 2.5 hours. After the reaction mixture was cooled to room temperature, it was diluted with 200 mL of ethyl acetate, and the organic phase was washed and extracted with a 2% sodium bicarbonate solution (200 mL) to collect the organic phase. The organic phase was washed with saturated sodium chloride aqueous solution (200 mL), dried over anhydrous sodium sulfate, filtered, and the filtrate was evaporated by rotation until dry to obtain 5.5 g of the target compound IV-1-A, with a yield of 96.3%.

[0581] Method 2: Compound IV-1-A-1 (5 g, 17.84 mmol) was added to trifluoroethanol (30 mL), protected with argon gas, and stirred at 40°C to dissolve. Then, HCl DMF solution (2.1 mL, 0.4 mol / L) was added, and the mixture was stirred at 40°C for 2.5 hours. After the reaction mixture was cooled to room temperature, it was added to 120 mL of aqueous sodium bicarbonate solution (1%, W / V), stirred, filtered by suction, and the filter cake was dried to obtain 5.3 g of the target compound IV-1-A, with a yield of 92.8%. 1 H NMR (400 MHz, DMSO-d6) δ 8.88 (t, J = 6.5 Hz, 1H), 7.54 (t, J = 6.0 Hz, 1H), 7.40-7.32 (m, 5H), 5.07 (s, 2H), 4.70 (d, J = 6.8 Hz, 2H), 4.03 (q, J = 9.4 Hz, 2H), 3.68 (d, J = 6.1 Hz, 2H).

[0582] Route 2:

[0583] [ka]

[0584] Step 1: Synthesis of (2-((hydroxymethyl)amino)-2-oxoethyl)benzyl carbamate (IV-1-A-3) Method 1: IV-1-A-2 (10.4 g, 50 mmol) was mixed with water (156 mL), aqueous formaldehyde solution (7.3 g, 90 mmol), and K2CO3 (0.69 g, 5 mmol), and the mixture was reacted at room temperature for 14 hours. The mixture was filtered, rinsed twice with water (50 mL), and vacuum-dried at 40°C for 4 hours to obtain 9.23 g of product. Yield: 77.5%.

[0585] Method 2: IV-1-A-2 (10.4 g, 50 mmol) was mixed with water (156 mL), aqueous formaldehyde solution (6.0 g, 75 mmol), and K2CO3 (0.69 g, 5 mmol), and the mixture was reacted at room temperature for 14 hours. The mixture was filtered, rinsed twice with water (50 mL), and vacuum-dried at 40°C to obtain 7.38 g of product. Yield: 62%. LCMS (ESI) [M+Na] + = 261.2 1 H NMR (400 MHz, DMSO-d6) :δ 8.48 (t, J = 6.1 Hz, 1H), 7.47 (t, J = 6.0 Hz, 1H), 7.44 - 7.25 (m, 5H), 5.60 (t, J = 6.6 Hz, 1H), 5.06 (s, 2H), 4.54 (t, J = 6.4 Hz, 2H), 3.62 (d, J = 6.1 Hz, 2H).

[0586] Step 2: Synthesis of (2-oxo-2-(((2,2,2-trifluoroethoxy)methyl)amino)ethyl)benzyl(IV-1-A) carbamate Method 1: Compound IV-1-A-3 (2.38 g, 10 mmol) was mixed with trifluoroethanol (14.4 mL, 6V) and HCl-DMF (1.25 mL, 0.5 mmol, 0.4 mol / L) and reacted at 40°C for 3 hours. The reaction system was cooled to 20°C, added dropwise to 2% NaHCO3 aqueous solution (58 mL), stirred for 0.5 hours, filtered, rinsed twice with water (12 mL), and vacuum-dried at 40°C for 2 hours to obtain 2.61 g of product. Yield: 81.5%. Purity: 98%.

[0587] Method 2: Compound IV-1-A-3 (10.0 g, 42 mmol) was mixed with trifluoroethanol (60 mL) and BF3-Et2O (0.3 g, 2.1 mmol, 48%), and the mixture was reacted at 40°C for 3 hours. The reaction system was cooled to 20°C, and the mixture was added dropwise to a 2% aqueous solution of NaHCO3 (245 mL). The mixture was stirred for 0.5 hours, filtered, rinsed twice with water (50 mL), and vacuum-dried at 40°C to obtain 10.6 g of the product. Yield: 78.8%. Purity: 97%.

[0588] Method 3: Compound IV-1-A-3 (10.0 g, 42 mmol) was mixed with trifluoroethanol (60 mL) and HCl-DMF (63 mL, 25.2 mmol, 0.4 mol / L) and reacted at 40°C for 3 hours. The reaction system was cooled to 20°C, and the mixture was added dropwise to 2% NaHCO3 aqueous solution (245 mL). The mixture was stirred for 0.5 hours, filtered, rinsed twice with water (50 mL), and vacuum-dried at 40°C to obtain 9.5 g of the product. Yield: 70.6%. Purity: 88%. LCMS (ESI) [M+Na] + = 343.2 1H NMR (400 MHz, DMSO-d6):δ 8.91 (t, J = 6.8 Hz, 1H), 7.57 (t, J = 6.1 Hz, 1H), 7.46 - 7.27 (m, 5H), 5.07 (s, 2H), 4.71 (d, J = 6.8 Hz, 2H), 4.04 (q, J = 9.4 Hz, 2H), 3.70 (d, J = 6.1 Hz, 2H).

[0589] II. Synthesis of IV-1-B

[0590] [ka]

[0591] IV-1-A-3 (20.0 g, 84 mmol) was mixed with methanol (120 mL) and HCl-DMF solution (10.5 mL, 0.4 mol / L), and the mixture was reacted at 40°C for 4 hours. The reaction mixture was then added dropwise to aqueous sodium bicarbonate solution (720 mL, 2% wt), concentrated under reduced pressure in a 40°C water bath to remove MeOH, extracted twice with EA (200 mL), combined the organic phases, washed once with saturated aqueous sodium chloride solution (100 mL), dried over anhydrous sodium sulfate for 0.5 hours, concentrated under reduced pressure until dry, and the resulting product was vacuum dried to obtain 19.4 g of IV-1-B. Yield: 91.5%. LCMS (ESI) [M+Na] + = 275.19 1 H NMR (400 MHz, DMSO-d6):δ 8.67 (s, 1H), 7.53 (s, 1H), 7.46-7.25 (m, 5H), 5.07 (s, 2H), 4.50 (s, 2H), 3.67 (s, 2H), 3.19 (s, 3H).

[0592] III. Synthesis of IV-1-C Step 1: Preparation of (9H-fluoren-9-yl)methyl(2-oxo-2-(((2,2,2-trifluoroethoxy)methyl)amino)ethyl)carbamate(IV-1-C)

[0593] [ka]

[0594] Compound IV-1-C-1 (10.00 g, 27.15 mmol) was added to 2,2,2-trifluoroethanol (60 mL), and the mixture was stirred at 40°C to dissolve it. Then, HCl / DMF (3.4 mL, 0.4 M) was added to the reaction mixture, and the mixture was stirred at 40°C for 2.0 hours. Ethyl acetate (200 mL) was added to the reaction mixture, and the mixture was diluted by stirring. The mixture was washed with 2% sodium bicarbonate solution (200 mL) and saturated brine solution (200 mL) for extraction, and the organic phase was separated. The organic phase was dried over anhydrous sodium sulfate, filtered, and concentrated to obtain 10.51 g of the target product (IV-1-C), with a yield of 94.8%. 1H NMR (400 MHz, DMSO-d6) δ 8.87 (t, J = 6.8 Hz, 1H), 7.92 (d, J = 7.5 Hz, 2H), 7.74 (d, J = 7.5 Hz, 2H), 7.62 (t, J = 6.3 Hz, 1H), 7.45 (t, J = 7.4 Hz, 2H), 7.36 (td, J = 7.4, 1.2 Hz, 2H), 4.70 (d, J = 6.8 Hz, 2H), 4.33 (d, J = 6.9 Hz, 2H), 4.29-4.22 (m, 1H), 4.03 (q, J = 9.4 Hz, 2H), 3.68 (t, J = 3.1 Hz, 2H). 4. Synthesis of IV-1-D Step 1: Synthesis of (9H-fluoren-9-yl)methyl(2-(((benzyloxy)methyl)amino)-2-oxoethyl)carbamate (IV-1-D)

[0595] [ka]

[0596] Compound IV-1-C-1 (50.0 g, 0.135 mol) was weighed and dissolved in DMF (300 mL), and benzyl alcohol (17.6 g, 0.163 mol) was added. While stirring at 25°C, HCl / EA (4 mol / L, 20.36 mL) was added all at once, and the reaction was continued with stirring for 4 hours. Ethyl acetate (1.5 L) was added to the reaction mixture, and the mixture was washed with 2% sodium bicarbonate (1 L), water (1 L x 2), and saline solution (1 L). The mixture was dried over anhydrous sodium sulfate and concentrated to dryness to obtain the crude product. The crude product was purified by silica gel column chromatography (eluent: EA / PE = 4 / 6), dried, and 40.0 g of the target product IV-1-D was obtained, with a yield of 71%. LCMS (ESI) [M+H] + =417.2

[0597] 5. Synthesis of IV-1-E Step 1: Synthesis of (9H-fluoren-9-yl)methyl(2-((isopropoxymethyl)amino)-2-oxoethyl)carbamate(IV-1-E)

[0598] [ka]

[0599] Compound IV-1-C-1 (10.00 g, 27.15 mmol) was added to isopropanol (60 mL), stirred at 40°C to dissolve, then HCl / DMF (3.4 mL, 0.4 M) was added to the reaction mixture, and the mixture was stirred at 40°C for 2.0 hours. Ethyl acetate (200 mL) was added to the reaction mixture, stirred to dilute, and the mixture was washed with 2% sodium bicarbonate solution (200 mL) and saturated brine solution (200 mL) for extraction. The organic phase was separated, dried over anhydrous sodium sulfate, filtered, and concentrated to obtain 9.50 g of the target product, with a yield of 95.0%. 1 H NMR (400 MHz, DMSO-d6) δ 8.56 (t, J = 6.6 Hz, 1H), 7.92 (d, J = 7.5 Hz, 2H), 7.75 (d, J = 7.4 Hz, 2H), 7.56 (t, J = 6.2 Hz, 1H), 7.45 (t, J = 7.4 Hz, 2H), 7.36 (t, J = 7.4 Hz, 2H), 4.57 (d, J = 6.5 Hz, 2H), 4.37-4.21 (m, 3H), 3.77-3.60 (m, 3H), 1.09 (dd, J =6.2,1.9 Hz, 6H).

[0600] 5. Synthesis of IV-1-F Step 1: Synthesis of (9H-fluoren-9-yl)methyl(2-oxo-2-(((2,2,3,3,3-pentafluoropropoxy)methyl)amino)ethyl)carbamate(IV-1-F)

[0601] [ka]

[0602] Compound IV-1-C-1 (10.00 g, 27.15 mmol) was added to 2,2,3,3,3-pentafluoro-1-propanol (40 mL), and the mixture was stirred at 40°C to dissolve it. Then, HCl / DMF (3.4 mL, 0.4 M) was added to the reaction mixture, and the mixture was stirred at 40°C for 2.0 hours. Ethyl acetate (200 mL) was added to the reaction mixture, and the mixture was diluted by stirring. The mixture was washed with 2% sodium bicarbonate solution (200 mL) and saturated brine solution (200 mL) for extraction, and the organic phase was separated. The organic phase was dried over anhydrous sodium sulfate, filtered, and concentrated to obtain 8.75 g of the target product, with a yield of 70.3%. 1 H NMR (400 MHz, DMSO-d6) δ 8.86 (t, J = 8.0 Hz, 1H), 7.90 (d, J = 8.0 Hz, 2H), 7.73-7.71 (d, J = 8.0, 2H), 7.60 (t, J = 8.0, 2H), 7.44-7.40 (m, 2H), 7.35-7.30(m, 2H), 4.70-4.68 (m, 2H), 4.31-4.20 (m, 2H), 4.25-4.22 (m, 1H), 4.13-4.06 (m, 2H), 3.67-3.65 (m, 2H).

[0603] Example 4: Synthesis of intermediate IV-2-1 1. Synthesis of intermediate IV-2-1-A Route 1: Synthesis of 2-amino-N-((2,2,2-trifluoroethoxy)methyl)acetamide (IV-2-1-A)

[0604] [ka]

[0605] Method 1: Compound IV-1-A (1.00 g, 3.29 mmol) was dissolved in THF (10 mL), and 10% Pd(OH)2 / C (100 mg) was added. After purging with hydrogen gas, the mixture was reacted at room temperature for 3 hours. DMF (10 mL) was added to the reaction mixture, filtered, and concentrated to remove THF, yielding a DMF solution of the target compound IV-2-1-A, which was used directly in the next reaction. Yields were calculated based on 100%.

[0606] Method 2: Compound IV-1-A (1.00 g, 3.29 mmol) was dissolved in THF (5 mL), and 5% Pd / C (50 mg) was added. After purging with hydrogen gas, the mixture was reacted at room temperature for 3 hours. DMF (5 mL) was added to the reaction mixture, filtered, and concentrated to remove THF, yielding a DMF solution of the target compound IV-2-1-A, which was used directly in the next reaction. Yields were calculated based on 100%.

[0607] Method 3: Compound IV-1-A (15.0 g, 49.35 mmol) was dissolved in THF (75 mL), and 5% Pd / C (750 mg) was added. After purging with hydrogen gas, the mixture was reacted at room temperature for 3 hours. DMF (75 mL) was added to the reaction mixture, filtered, and concentrated to remove THF, yielding a DMF solution of the target compound IV-2-1-A, which was used directly in the next reaction. Yields were calculated based on 100%. The nuclear magnetic hydrogen spectrum of the HOBt salt of compound Ia-A-3 is: 1 H NMR(400MHz,DMSOd6δ9.18(br,1H),7.79-7.71(m,1H),7.49-7.41(m,1H),7.2 5-7.18(m,2H),4.74(d,J=4.9Hz,2H),4.06(q,J=9.4Hz,2H),3.47(s,2H).

[0608] Route 2: Preparation of 2-amino-N-((2,2,2-trifluoroethoxy)methyl)acetamide (IV-2-1-A)

[0609] [ka]

[0610] IV-1-C (57.0 g, 139.57 mmol) was dissolved in a solution of DMF (350 mL) and diethylamine (17.5 mL). The mixture was stirred at 25±5°C for 1 hour and then concentrated under reduced pressure at 35°C for 30 minutes. A DMF solution of 2-amino-N-((2,2,2-trifluoroethoxy)methyl)acetamide (IV-2-1-A) was obtained and used directly in the next reaction. The conversion rate was calculated based on 100%.

[0611] 2. Synthesis of intermediate IV-2-1-B Synthesis of 2-amino-N-(methoxymethyl)acetamide (IV-2-1-B)

[0612] [ka]

[0613] Compound IV-1-B (11.0 g, 43.6 mmol) was mixed with THF (40 mL), MeOH (40 mL), and Pd / C (550 mg, 10%, 55% water) and reacted at 30°C for 7 hours under a hydrogen gas atmosphere. After the reaction was complete, DMF (55 mL) was added, and the mixture was concentrated under reduced pressure to remove THF and MeOH. The mixture was then directly added to the next step without purification. The yield was calculated based on 100%. LCMS (ESI) [M+H] + = 119.21

[0614] 3. Synthesis of intermediate IV-2-1-D Synthesis of 2-amino-N-((benzyloxy)methyl)acetamide (IV-2-1-D)

[0615] [ka]

[0616] Compound IV-1-D (38.0 g, 0.091 mol) was dissolved in a solution of DMF (240 mL) and diethylamine (12 mL). The mixture was stirred at 25°C for 1 hour, and the reaction mixture was concentrated under reduced pressure at 35°C for 30 minutes. The resulting DMF solution of IV-2-1-D was used directly in the next reaction. The conversion rate was calculated based on 100%.

[0617] 4. Synthesis of intermediate IV-2-1-E Synthesis of 2-amino-N-((isopropoxy)methyl)acetamide (IV-2-1-E)

[0618] [ka]

[0619] Compound IV-1-E (22.0 g, 59.83 mmol) was dissolved in a solution of DMF (150 mL) and diethylamine (7.5 mL). The mixture was stirred at 25°C for 1 hour. After the reaction was complete, the reaction solution was concentrated under reduced pressure at 35°C for 30 minutes to obtain a DMF solution of IV-2-1-E, which was used directly in the next reaction (conversion rate was calculated based on 100%).

[0620] 5. Synthesis of intermediate IV-2-1-F Synthesis of 2-amino-N-((2,2,3,3,3-pentafluoropropoxy)methyl)acetamide (IV-2-1-F)

[0621] [ka]

[0622] Compound IV-1-F (466.0 mg, 1.00 mmol) was dissolved in a solution of DMF (10 mL) and diethylamine (0.5 mL). The mixture was stirred at 25°C for 1 hour, and the reaction solution was concentrated under reduced pressure at 35°C for 30 minutes to obtain a DMF solution of 2-amino-N-((2,2,3,3,3-pentafluoropropoxy)methyl)acetamide (IV-2-1-F), which was used directly in the next reaction (conversion rate was calculated based on 100%).

[0623] Example 5: Synthesis of Intermediate IV-2 1. Synthesis of IV-2-A Synthesis of ((10S,13S)-10-(4-(dipropylamino)butyl)-1,1,1-trifluoro-14-methyl-6,9,12-trioxo-3-oxa-5,8,11-triazapentadecane-13-yl)benzyl(IV-2-A)carbamate

[0624] [ka]

[0625] Method 1: Compound IV-2-2-B (1.52 g, 3.29 mmol) was added to the DMF solution of compound IV-2-1-A (3.29 mmol) obtained in the previous step. The temperature was controlled to -10°C, DMTMM (1.16 g, 3.98 mmol) was added, and the mixture was reacted for 1.5 hours. EA (50 mL) was added to the reaction system, and the mixture was washed sequentially with saturated NaHCO3 aqueous solution (15 mL x 3) and saturated saline solution (15 mL). The organic phase was dried over anhydrous sodium sulfate, filtered by suction, and the filtrate was concentrated to dryness. The resulting residue was dissolved in EA (3 mL), added to n-heptane (30 mL), stirred to precipitate a solid, filtered by suction, and the filtration cake was 1.55 g of the target compound, with a yield of 74.9%.

[0626] Method 2: Compound IV-2-2-A (33.4 g, 72.3 mmol) was added to the DMF solution of compound IV-2-1-A (139.57 mmol) obtained in the previous step. The temperature was controlled to -15°C, DMTMM (23.2 g, 79.6 mmol) was added, and the mixture was reacted for 1.5 hours. EA (1000 mL) was added to the reaction system, and the mixture was washed sequentially with saturated NaHCO3 aqueous solution (300 mL x 3) and saturated brine (300 mL). The organic phase was dried over anhydrous sodium sulfate, filtered by suction, and the filtrate was concentrated to dryness. The resulting residue was dissolved in MTBE (60 mL), added to n-heptane (600 mL), stirred to precipitate a solid, filtered by suction, and the filtration cake was 31.2 g of the target compound, with a yield of 75.4%. LCMS (ESI) [M+H] += 632.3. 1 H NMR (400 MHz, DMSO-d6) δ 8.85 - 8.73 (m, 1H), 8.37 - 8.26 (m, 1H), 8.03 (d, J = 7.0 Hz, 1H), 7.40-7.32 (m, 6H), 5.10 - 5.01 (m, 2H), 4.73-4.66 (m, 2H), 4.29 - 4.20 (m, 1H), 4.02 (q, J = 9.4 Hz, 2H), 3.93 (dd, J = 13.8, 6.6 Hz, 1H), 3.85 - 3.67 (m, 2H), 2.38-2.32 (m, 6H), 2.02-1.96 (m, 1H), 1.75 - 1.51 (m, 2H), 1.46 - 1.23 (m, 8H), 0.90-0.82(m, 12H).

[0627] 2. Synthesis of IV-2-B Synthesis of ((9S,12S)-9-(4-(dipropylamino)butyl)-13-methyl-5,8,11-trioxo-2-oxa-4,7,10-triazatetradecane-12-yl)benzyl(IV-2-B)carbamate

[0628] [ka]

[0629] IV-2-2-B (23.6 g, 45.8 mmol, 90% wt) was added to the DMF solution of IV-2-1-B (43.6 mmol) from the previous step, the temperature was cooled to -15°C, and the temperature was controlled to -15 to -10°C. DMTMM monohydrate (12.9 g, 43.6 mmol) was added and the mixture was reacted for 3 hours. NaHCO3 aqueous solution (500 mL, 5% wt) was added to the reaction mixture, and the mixture was extracted with EA (200 mL x 4). The organic phases were combined, washed once with saturated sodium chloride aqueous solution (200 mL), dried over anhydrous sodium sulfate, and concentrated under reduced pressure to obtain the crude product. The crude product was purified by column chromatography (MeOH / DCM = 1%~10%) to obtain 17.5 g of IV-2-B. Yield: 71.2%. LCMS (ESI) [M+H] + = 564.46 Formate: 1 H NMR(400MHz,DMSO-d6)δ 8.57(t,J=6.6Hz,1H),8.33-8.21(m,2H),8.05(d,J=7.3Hz,1H),7.50-7.15(m,6H),5.11-4.98(m,2H),4.54-4.37(m,2H),4 .31-4.14(m,1H),3.96-3.83(m,1H),3.81-3.57(m,2H),3.15(s,3H),2.49(s,6H),2.05-1.10(m,11H),0.93-0.75(m,12H).

[0630] 3. Synthesis of IV-2-C Synthesis of (9H-fluoren-9-yl)methyl((10S,13S)-10-(4-(dipropylamino)butyl)-1,1,1-trifluoro-14-methyl-6,9,12-trioxo-3-oxo-5,8,11-triazapentadecane-13-yl)carbamate(IV-2-C)

[0631] [ka]

[0632] IV-2-2-A (70.0 g, 126.88 mmol) and DMF (350 mL) were added to a DMF solution of IV-2-1-A (139.57 mmol). The reaction mixture was cooled to -15°C, DMTMM (42.13 g, 152.26 mmol) was added, and the mixture was stirred at -10°C for 2 hours. The reaction mixture was poured into DCM (2000 mL), and the organic phase was washed with 2% NaHCO3 aqueous solution (1000 mL x 3), water (1000 mL), and saturated NaCl aqueous solution (500 mL). The organic phase was dried over anhydrous sodium sulfate, insoluble matter was filtered off, and the mixture was concentrated to obtain the crude product. This was purified by silica gel column chromatography (eluent: 0-7% MeOH / DCM) to obtain 70 g of (9H-fluoren-9-yl)methyl((10S,13S)-10-(4-(dipropylamino)butyl-1,1,1-trifluoro-14-methyl-6,9,12-trioxo-3-oxo-5,8,11-triazapentadecane-13-yl)carbamate (IV-2-C) in a yield of 81%. LCMS (ESI) [M+H] + =720.5 1 H NMR (400 MHz,DMSO-d6) δ 8.78 (t, J = 8.0 Hz, 1H), 8.28 (t, J = 8.0 Hz, 1H), 8.02 (d, J = 4.0 Hz, 1H), 7.90-7.88 (m, 2H), 7.72 (t, J = 8.0 Hz, 2H), 7.46-7.39 (m, 3H), 7.34-7.30(m, 2H), 4.71-4.62 (m, 2H), 4.30-4.24 (m, 4H), 4.03-3.96 (m, 2H), 3.90-3.86 (m, 1H), 3.80-3.66 (m, 2H), 2.35-2.15 (m, 6H), 1.99-1.94 (m, 1H), 1.66-1.63 (m, 1H), 1.56-1.53 ​​(m, 1H), 1.36-1.26 (m, 8H), 0.89-0.77 (m, 12H).

[0633] 4. Synthesis of IV-2-D Synthesis of (9H-fluoren-9-yl)methyl((9S,12S)-9-(4-(dipropylamino)butyl)-13-methyl-5,8,11-trioxo-1-phenyl-2-oxo-4,7,10-triazatetradecane-12-yl)carbamate (IV-2-D)

[0634] [ka]

[0635] IV-2-2-A (49.3 g, 0.089 mmol) was added to a DMF solution of IV-2-1-D (0.091 mol), the reaction mixture was cooled to -15°C, DMTMM (26.9 g, 0.091 mol) was added, and the mixture was stirred at -15°C for 2 hours. The reaction mixture was poured into DCM (720 mL) and washed sequentially with 2% NaHCO3 aqueous solution (500 mL x 2) and saturated NaCl aqueous solution (500 mL). The organic phase was concentrated, and the crude product was purified by silica gel column chromatography (eluent: 0-7% MeOH / DCM) to obtain 55 g of (9H-fluoren-9-yl)methyl((9S,12S)-9-(4-(dipropylamino)butyl)-13-methyl-5,8,11-trioxo-1-phenyl-2-oxo-4,7,10-triazatetradecane-12-yl)carbamate (IV-2-D) in 85% yield. LCMS (ESI) [M+H] + =728.6 1H NMR (400 MHz, DMSO-d6) δ 8.69 (t, J = 6.8 Hz, 1H), 8.27(t, J = 5.8 Hz, 1H), 8.03 (d, J = 7.2 Hz, 1H), 7.93-7.87 (m, 2H), 7.75 (t, J = 7.0 Hz, 2H), 7.48-7.30 (m, 10H), 4.71-4.56 (m, 2H), 4.47 (s, 2H), 4.30-4.25 (m, 4H), 3.93-3.69(m, 3H), 2.32-2.27 (m, 6H), 2.03-1.98 (m, 1H), 1.71-1.55 (m, 2H), 1.40-1.30 (m, 8H), 0.92-0.80(m, 12H).

[0636] 5. Synthesis of IV-2-E Synthesis of (9H-fluoren-9-yl)methyl((10S,13S)-10-(4-(dipropylamino)butyl)-2,14-dimethyl-6,9,12-trioxo-3-oxo-5,8,11-triazapentadecane-13-yl)carbamate(IV-2-E)

[0637] [ka]

[0638] IV-2-2-A (30.0 g, 54.38 mol) was added to a DMF solution of IV-2-1-E (59.83 mmol). The reaction mixture was cooled to -15°C, DMTMM (18.0 g, 65.26 mmol) was added, and the mixture was stirred at -10°C for 2 hours. The reaction mixture was poured into DCM (1 L). The organic phase was washed sequentially with 2% NaHCO3 aqueous solution (500 mL x 3), water (500 mL), and saturated NaCl aqueous solution (500 mL). The organic phase was concentrated, and the crude product was subjected to silica gel column chromatography (eluent: 0-7% MeOH / DCM) to obtain 30.0 g of the target product IV-2-E, with a yield of 81%. LCMS (ESI) [M+H] + = 680.5 1H NMR (400 MHz, DMSO-d6) δ 8.54 (t, J = 8.0 Hz, 1H), 8.27 (t, J = 8.0 Hz, 1H), 8.08 (d, J = 8.0 Hz, 1H), 7.90-7.88 (m, 2H), 7.75-7.73 (m, 2H), 7.46-7.40 (m, 3H), 7.34-7.30(m, 2H), 4.56-4.52 (m, 2H), 4.34-4.19 (m, 4H), 3.91-3.87 (m, 1H), 3.71-3.63 (m, 3H), 3.00-2.75 (m, 6H), 2.02-1.97 (m, 1H), 1.75-1.54 (m, 8H), 1.37-1.24 (m, 2H), 1.06-1.04 (m, 6H), 0.93-0.77 (m, 12H).

[0639] 6. Synthesis of IV-2-F Synthesis of (9H-fluoren-9-yl)methyl((11S,14S)-11-(4-(dipropylamino)butyl)-1,1,1,2,2-pentafluoro-15-methyl-7,10,13-trioxo-4-oxa-6,9,12-triazahexadecane-14-yl)carbamate (IV-2-F)

[0640] [ka]

[0641] IV-2-2-A (500.0 mg, 0.91 mmol) was added to a solution of IV-2-1-F (1.00 mmol). The reaction mixture was cooled to -15°C, DMTMM (300.0 mg, 1.09 mmol) was added, and the mixture was stirred at -10°C for 2 hours. The reaction mixture was poured into DCM (50 mL). The organic phase was washed sequentially with 2% NaHCO3 aqueous solution (20 mL x 3), water (10 mL), and saturated NaCl aqueous solution (10 mL). The organic phase was concentrated, and the crude product was subjected to silica gel column chromatography (eluent: 0-7% MeOH / DCM) to obtain 440.0 mg of the target product (IV-2-F), with a yield of 67%. LCMS (ESI) [M+H] + = 770.48 1 H NMR (400 MHz, DMSO-d6) δ 8.79 (t, J = 8.0 Hz, 1H), 8.27 (t, J = 4.0 Hz, 1H), 8.00 (d, J = 8.0 Hz, 1H), 7.90-7.88 (m, 2H), 7.73-7.70 (m, 2H), 7.45-7.39 (m, 3H), 7.33-7.30(m, 2H), 4.71-4.63 (m, 2H), 4.33-4.22 (m, 4H), 4.11-4.04 (m, 2H), 3.90-3.86 (m, 1H), 3.79-3.67 (m, 2H), 2.30-2.20 (m, 6H), 2.01-1.94 (m, 1H), 1.66-1.52 (m, 2H), 1.35-1.23 (m, 8H), 0.86-0.76 (m, 12H).

[0642] 7. Synthesis of IV-2-G Synthesis of (9H-fluoren-9-yl)methyl((S)-1-((S)-6-(dipropylamino)-1-((2-((hydroxymethyl)amino)-2-oxoethyl)amino)-1-oxohexane-2-yl)amino)-3-methyl-1-oxobutan-2-yl)carbamate (IV-2-G)

[0643] [ka]

[0644] IV-2-D (73 mg, 0.10 mmol) was dissolved in tetrahydrofuran (1.4 mL), and 10% palladium carbon (28 mg) and HCl / EA (4 mol / L, 25 μL) were added sequentially. The mixture was purged three times with hydrogen gas and stirred at 25°C for 12 hours under a hydrogen gas atmosphere. Insoluble matter was removed by filtration, the filtrate was concentrated, and purified by prep-HPLC (chromatographic conditions: acetonitrile / 0.05% FA aqueous solution: 5%~40%) to obtain 345 mg of IV-3-G formate in a yield of 54%. LCMS (ESI) [M+H] + =638.4 1 H NMR (400 MHz, DMSO-d6) δ 9.09(s, 1H), 8.47-8.46 (m, 1H), 8.24-8.23 (m, 1H), 8.12-8.08 (m, 1H), 7.95-7.72 (m, 2H), 7.78-7.75 (m, 2H), 7.52-7.33 (m, 5H), 4.58-4.50 (m,3H), 4.36-4.31 (m, 2H), 4.27-4.21(m, 2H), 3.92-3.89 (m, 1H), 3.72-3.71 (m, 2H), 2.99-2.96 (m, 6H), 2.03-1.98(m, 1H), 1.74-1.72 (m, 1H), 1.60-1.58 (m, 7H), 1.33 (s, 2H), 0.89-0.90 (m, 12H).

[0645] Example 6: Synthesis of X-3-1 1. Synthesis of X-3-1-A Route 1: Synthesis of (S)-2-((S)-2-amino-3-methylbutanamide)-6-(dipropylamino)-N-(2-oxo-2-(((2,2,2-trifluoroethoxy)methyl)amino)ethyl)hexanamide (X-3-1-A)

[0646] [ka]

[0647] Method 1: Compound IV-2-A (3.4 g, 5.4 mmol) was dissolved in 34 mL of MeOH, 680 mg of 10% Pd(OH)2 / C was added, and the mixture was purged with hydrogen gas and reacted overnight. 680 mg of 10% Pd(OH)2 / C as a catalyst was added and the reaction was continued for 24 hours. After filtering the reaction mixture, the filtrate was concentrated under reduced pressure to obtain 2.5 g of the target compound X-3-1-A, with a yield of 93.5%.

[0648] Method 2: Compound IV-2-A (4 g, 6.3 mmol) was dissolved in 100 mL of methanol. Using a fully automated microreaction hydrogenation apparatus, palladium hydroxide supported on aluminum oxide was used as a catalyst. The program was set to: temperature 50°C, pressure 2.5 MPa, liquid flow rate 0.3 mL / min, and hydrogen gas flow rate 30 mL / min. The effluent was concentrated under reduced pressure to obtain 3.0 g of the target compound X-3-1-A, with a yield of 95.1%. LCMS (ESI) [M+H] + = 498.3. 1 H NMR (400 MHz, DMSO-d6) δ 8.89 - 8.77 (m, 1H), 8.42 - 8.30 (m, 1H), 8.14 (s, 1H), 4.70 (p, J = 10.3 Hz, 2H), 4.28 (s, 1H), 4.02 (q, J = 9.4 Hz, 2H), 3.80 (dd, J = 15.7, 4.9 Hz, 1H), 3.75 - 3.67 (m, 1H), 3.20 (brs, 2H), 3.11 (d, J = 4.8 Hz, 1H), 2.35 (dd, J = 14.4, 7.3 Hz, 6H), 2.04 - 1.90 (m, 1H), 1.76 - 1.51 (m, 2H), 1.45 - 1.20 (m, 8H), 0.95 - 0.77 (m, 12H).

[0649] Route 2: Synthesis of (S)-2-((S)-2-amino-3-methylbutanamide)-6-(dipropylamino)-N-(2-oxo-2-(((2,2,2-trifluoroethoxy)methyl)amino)ethyl)hexanamide (X-3-1-A)

[0650] [ka]

[0651] Compound IV-2-C (1.7 g, 2.4 mmol) was dissolved in DMF (10 mL), DEA (0.5 mL) was added, and the reaction mixture was stirred at 25°C for 1 hour. Tetrahydrofuran (15 mL) was added to the reaction mixture, and the mixture was concentrated under reduced pressure. This procedure was repeated three times to obtain a DMF solution of the target compound X-3-1-A, which was used directly in the next reaction (conversion rate was calculated based on 100%). LCMS (ESI) [M+H] + = 498.3

[0652] 2. Synthesis of X-3-1-B Synthesis of (S)-2-((S)-2-amino-3-methylbutanamide)-6-(dipropylamino)-N-(2-((2-methoxymethyl)amino)-2-oxoethyl)hexanamide (X-3-1-B)

[0653] [ka]

[0654] Compound IV-2-B (7.0 g, 12.4 mmol) was mixed with MeOH (70 mL) and Pd / C (2.1 g, 10%, 55% water) and reacted at 30°C for 48 hours, with the reaction monitored by LC-MS. After the reaction was complete, the mixture was concentrated to remove the MeOH, 63 mL of ACN was added, and the mixture was used directly for the next step without purification (calculated based on 100% yield). LCMS (ESI) [M+H] + = 430.51 1H NMR (400 MHz, DMSO-d6) δ 8.59 (t, J = 6.6 Hz, 1H), 8.33 (t, J = 5.9 Hz, 1H), 8.21 (d, J = 7.1 Hz, 1H), 4.52-4.36 (m, 2H), 4.32-4.13 (m, 1H), 3.80-3.57 (m, 2H), 3.18-3.03 (m, 4H), 2.44-2.23 (m, 6H), 2.06-1.91 (m, 1H), 1.76-1.47 (m, 2H), 1.45-1.13 (m, 8H), 0.96-0.71 (m, 12H).

[0655] Example 7: Synthesis of X-3 1. Synthesis of X-3a Synthesis of N-((10S,13S)-10-(4-(dipropylamino)butyl)-1,1,1-trifluoro-14-methyl-6,9,12-trioxo-3-oxa-5,8,11-triazapentadecan-13-yl)-6-(2-(methylsulfonyl)pyrimidine-5-yl)hexa-5-inylamide (X-3a)

[0656] [ka]

[0657] Method 1: Under argon gas protection, X-1-B (2.95 g, 11.0 mmol), DCM (20 mL), and thionyl chloride (3.93 g, 33.0 mmol) were sequentially added to the reaction flask and stirred at room temperature for 3 hours. The solvent was removed under reduced pressure to obtain X-1-A, which was used directly in the next reaction (conversion rate was calculated based on 100%). Compound X-3-1-A (5.0 g, 10.0 mmol) was dissolved in 35 mL of acetonitrile, cooled to 10°C, DIPEA (0.26 g, 2.0 mmol) was added, and a solution of compound X-1-A (11.0 mmol) in acetonitrile (15 mL) was added dropwise. The reaction was allowed to proceed for 1 hour, methyl tert-butyl ether (500 mL) was added to the reaction mixture to precipitate the solid, which was then filtered by suction. The filtered cake was dried to obtain 7.13 g of the hydrochloride salt of the target compound, with a yield of 91.0%.

[0658] Method 2: Under argon gas protection, X-1-B (32.2 g, 120 mmol), DCM (220 mL), and thionyl chloride (42.9 g, 360 mmol) were sequentially added to the reaction flask and stirred at room temperature for 3 hours. The solvent was removed under reduced pressure to obtain X-1-A, which was used directly in the next reaction (conversion rate was calculated based on 100%). Compound X-3-1-A (50.0 g, 100 mmol) was dissolved in 350 mL of acetonitrile, cooled to 10°C, and DIPEA (3.25 g, 25 mmol) was added. A solution of compound X-1-A (prepared from acid and thionyl chloride and used immediately) (120 mmol) in acetonitrile (150 mL) was added dropwise. The mixture was allowed to react for 1 hour, and 2-methyltetrahydrofuran (2.1 L) was added to the reaction mixture to precipitate the solid. The mixture was filtered by suction, and the filter cake was dried to obtain 71.8 g of the hydrochloride salt of the target compound, with a yield of 91.6%. LCMS (ESI) [M+H] + = 748.4 1H NMR (400 MHz, DMSO-d6) δ 9.15 (s, 2H), 8.78 (t, J = 6.8 Hz, 1H), 8.24 (t, J = 5.8 Hz, 1H), 8.05 (d, J = 7.3 Hz, 1H), 7.95 (d, J = 8.6 Hz, 1H), 4.75-4.66 (m, 2H), 4.24-4.19 (m, 2H), 4.03 (q, J = 9.4 Hz, 2H), 3.78-3.76 (m, 2H), 3.44 (s, 3H), 2.58 (t, J = 7.1 Hz, 2H), 2.46-2.29 (m, 8H), 2.03-1.95 (m, 1H), 1.89-1.81 (m, 2H), 1.73-1.66 (m, 1H), 1.62-1.56 (m, 1H), 1.41-1.36 (m, 6H), 1.31-1.25 (m, 2H), 0.89-0.83 (m, 12H).

[0659] 2. Synthesis of X-3b Synthesis of N-((9S,12S)-9-(4-(dipropylamino)butyl)-13-methyl-5,8,11-trioxo-2-oxa-4,7,10-triazatetradecane-12-yl)-6-(2-(methylsulfonyl)pyrimidine-5-yl)hexa-5-inylamide (X-3b)

[0660] [ka]

[0661] A solution of compound X-3-1-B (12.4 mmol) in ACN was prepared for use by adding DIPEA (321 mg, 2.48 mmol). Compound X-1-B (3.66 g, 13.6 mmol) was added to dichloromethane (40 mL), thionyl chloride (4.85 g, 40.8 mmol) was added, and the mixture was reacted at 30°C with stirring for 3.0 hours. The mixture was concentrated to dryness under reduced pressure in a 40°C water bath, dissolved in ACN (7 mL), and the temperature was controlled to 10-15°C. The mixture was then added dropwise to the prepared ACN solution of compound X-3-1-B. After reacting for 2 hours, MTBE (490 mL) was added, the mixture was filtered, dried, and compound (5.40 g, 7.5 mmol) was obtained. Yield: 60.5%. LCMS (ESI) [M+H] + =680.42 1 H NMR (400 MHz, DMSO-d6) δ 9.12 (s, 2H), 8.51 (t, J = 6.6 Hz, 1H), 8.27 (s, 1H), 8.19 (t, J = 5.9 Hz, 1H), 8.04 (d, J = 7.3 Hz, 1H), 7.95 (d, J = 8.6 Hz, 1H), 4.57-4.35 (m, 2H), 4.25-4.04 (m, 2H), 3.82-3.62 (m, 2H), 3.41 (s, 3H), 3.14 (s, 3H), 2.54 (t, J = 7.1 Hz, 2H), 2.43-2.18 (m, 8H), 2.02-1.88 (m, 1H), 1.87-1.73 (m, 2H), 1.72-1.45 (m, 2H), 1.43-1.16 (m, 8H), 0.92-0.73 (m, 12H).

[0662] III. Synthesis of X-3a Synthesis of N-((10S,13S)-10-(4-(dipropylamino)butyl)-1,1,1-trifluoro-14-methyl-6,9,12-trioxo-3-oxa-5,8,11-triazapentadecan-13-yl)-6-(2-(methylsulfonyl)pyrimidine-5-yl)hexa-5-inylamide (X-3a)

[0663] [ka]

[0664] At 25°C, X-1-B (772 mg, 2.9 mmol) and DMTMM (849 mg, 2.9 mmol) were sequentially added to the DMF solution of X-3-1-A obtained in Step 1, and the mixture was stirred and reacted for 1 hour. The reaction mixture was purified by prep-HPLC and lyophilized to obtain 1.3 g of N-((10S,13S)-10-(4-(dipropylamino)butyl)-1,1,1-trifluoro-14-methyl-6,9,12-trioxo-3-oxa-5,8,11-triazapentadecane-13-yl)-6-(2-(methylsulfonyl)pyrimidine-5-yl)hexa-5-inylamide (X-3a) in a yield of 76.5%. LCMS (ESI) [M+H] + = 748.4 1 H NMR (400 MHz, DMSO-d6) δ 9.15 (s, 2H), 8.78 (t, J = 6.8 Hz, 1H), 8.24 (t, J = 5.8 Hz, 1H), 8.05 (d, J = 7.3 Hz, 1H), 7.95 (d, J = 8.6 Hz, 1H), 4.75-4.66 (m, 2H), 4.24-4.19 (m, 2H), 4.03 (q, J = 9.4 Hz, 2H), 3.78-3.76 (m, 2H), 3.44 (s, 3H), 2.58 (t, J = 7.1 Hz, 2H), 2.46-2.29 (m, 8H), 2.03-1.95 (m, 1H), 1.89-1.81 (m, 2H), 1.73-1.66 (m, 1H), 1.62-1.56 (m, 1H), 1.41-1.36 (m, 6H), 1.31-1.25 (m, 2H), 0.89-0.83 (m, 12H).

[0665] Example 8: Synthesis of IIa Route 1: Synthesis of N-((11S,14S)-11-(4-(dipropylamino)butyl)-1-((S)-7-ethyl-7-hydroxy-8,11-dioxo-7,8,11,13-tetrahydro-10H-[1,3]dioxolo[4,5-g]pyrano[3',4':6,7]indolidino[1,2-b]quinoline-14-yl)-15-methyl-7,10,13-trioxo-4-oxa-6,9,12-triazahexadecane-14-yl)-6-(2-(methylsulfonyl)pyrimidine-5-yl)hexa-5-inylamide (IIa)

[0666] [ka]

[0667] Method 1: At room temperature, compound III (2.0 g, 4.4 mmol) was dissolved in dry DMF (10 mL), and HCl solution in DMF (3.3 mL, 4.02 mol / L) was added and stirred until dissolved. Hydrochloride salt of X-3a obtained in Step 8 (6.97 g, 8.8 mmol) was added, and the reaction was stirred at room temperature for 3 hours under nitrogen gas protection. DCM (72 mL) was added to the reaction mixture, and acetonitrile / water mixture (72 mL, v:v=30:70) was added, and the liquid-liquid was separated to collect the aqueous and organic phases separately. The organic phase was washed with 2% aqueous sodium bicarbonate solution (72 mL), the two aqueous phases were combined, and extracted twice with DCM (72 mL × 2). The three organic phases were combined, washed sequentially with pure water (72 mL) and saturated saline solution (72 mL), the organic phase was dried over anhydrous sodium sulfate, and filtered. The filtrate was allowed to stand at -20°C for 12 hours, insoluble matter was removed by filtration, and the filtrate was concentrated to obtain the crude product. The crude product was separated and purified by preparative HPLC to obtain 2.5 g of the formate of the target product IIa, with a yield of 51.2%. LCMS (ESI) [M+H] + = 1098.7 1H NMR (400 MHz, DMSO-d6) δ 9.10 (s, 2H), 8.59 (t, J = 6.6 Hz, 1H), 8.25 - 8.14 (m, 2H), 8.02 (d, J = 7.4 Hz, 1H), 7.93 (d, J = 8.5 Hz, 1H), 7.58 (s, 1H), 7.50 (s, 1H), 7.24 (s, 1H), 6.28 (s, 2H), 5.42 (d, J = 2.2 Hz, 2H), 5.23 (s, 2H), 4.66 - 4.52 (m, 2H), 4.26 - 4.11 (m, 2H), 3.80 - 3.64 (m, 2H), 3.49 (t, J = 6.0 Hz, 2H), 3.40 (s, 3H), 3.15-3.06 (m, 2H), 2.54 (d, J = 7.3 Hz, 2H), 2.44 - 2.25 (m, 8H), 1.99 - 1.77 (m, 7H), 1.73 - 1.45 (m, 2H), 1.39 - 1.20 (m, 8H), 0.89 - 0.77 (m, 15H).

[0668] Method 2: To the solids of compound III (10.0 g, 22.2 mmol) and the hydrochloride salt of X-3a (35.0 g, 44.4 mmol), 200 mL of toluene was added, and the mixture was stirred under reflux at 110°C for 2.0 hours using a water splitter to remove the water. Toluene was then removed by rotary evaporation, 60 mL of DMF was added, and then diethyl boron trifluoride ether (9.5 g, 66.6 mmol) was added. The mixture was stirred at 30°C and reacted for 16 hours. 360 mL of DCM was added to the reaction mixture, stirred to dilute, and washed with 300 mL x 2 of (2% sodium bicarbonate:saturated saline = 7:3) and 300 mL of (water:saturated saline = 7:3). The organic phase was dried, filtered, and concentrated until dry to obtain the crude product. The crude product was separated and purified by prep-HPLC to obtain 16.7 g of the formate salt of the target product IIa, with a yield of 68.3%. LCMS (ESI) [M+H] + = 1098.7 1H NMR (400 MHz, DMSO-d6) δ 9.09 (s, 2H), 8.57 (t, J = 6.6 Hz, 1H), 8.22-8.12 (m, 2H), 7.99 (d, J = 7.4 Hz, 1H), 7.91 (d, J = 8.6 Hz, 1H), 7.57 (s, 1H), 7.49 (s, 1H), 7.24 (s, 1H), 6.45 (s, 1H), 6.28 (s, 2H), 5.42 (d, J = 3.1 Hz, 2H), 5.23 (s, 2H), 4.58 (q, J = 10.2, 8.3 Hz, 2H), 4.26-4.11 (m, 2H), 3.81-3.64 (m, 2H), 3.50 (t, J = 6.1 Hz, 2H), 3.40 (s, 3H), 3.10 (t, J = 8.1 Hz, 2H), 2.54 (d, J = 7.1 Hz, 2H), 2.42-2.25 (m, 8H), 2.00-1.74 (m, 7H), 1.70-1.48 (m, 2H), 1.40-1.22 (m, 8H), 0.91 -0.74 (m, 15H).

[0669] Method 3: Add 200 mL of toluene to the solids of compound III (10.0 g, 22.2 mmol) and the hydrochloride salt of X-3a (35.0 g, 44.4 mmol), and remove the water by stirring under reflux at 110°C for 2.0 hours using a water splitter. Remove the toluene by rotary evaporation, add 60 mL of NMP, and stir at 120°C for 5 hours. Cool the reaction mixture to room temperature, add it dropwise to 360 mL of EA, stir for 1 hour, filter by suction, and purify the filtration cake by column chromatography (MeOH / DCM = 1%~20%) to obtain 16.4 g of the hydrochloride salt I of the target product I, with a yield of 67.2%. LCMS (ESI) [M+H] + = 1098.7 1H NMR (400 MHz, DMSO-d6) δ 9.81 (s, 1H), 9.11 (s, 2H), 8.65 (t, J = 6.6 Hz, 1H), 8.23 ​​(t, J = 5.8 Hz, 1H), 8.10 (d, J = 7.4 Hz, 1H), 7.97 (d, J = 8.5 Hz, 1H), 7.58 (s, 1H), 7.50 (s, 1H), 7.24 (s, 1H), 6.49 (s, 1H), 6.28 (d, J = 1.8 Hz, 2H), 5.42 (s, 2H), 5.22 (s, 2H), 4.65 - 4.52 (m, 2H), 4.25 (q, J = 7.3 Hz, 1H), 4.15 (dd, J = 8.5, 6.8 Hz, 1H), 3.74 (d, J = 5.9 Hz, 2H), 3.49 (t, J = 6.1 Hz, 2H), 3.40 (s, 3H), 3.13 - 3.03 (m, 2H), 2.95 (dt, J = 11.5, 5.0 Hz, 6H), 2.54 (t, J = 7.0 Hz, 2H), 2.36 (dq, J = 24.7, 7.4 Hz, 2H), 2.04 - 1.54 (m, 15H), 1.37 - 1.25 (m, 2H), 0.94 - 0.72 (m, 15H).

[0670] Route 2: Synthesis of (N-((11S,14S)-11-(4-(dipropylamino)butyl)-1-((S)-7-ethyl-7-hydroxy-8,11-dioxo-7,8,11,13-tetrahydro-10H-[1,3]dioxolo[4,5-g]pyrano[3',4':6,7]indolidino[1,2-b]quinoline-14-yl)-15-methyl-7,10,13-trioxo-4-oxa-6,9,12-triazahexadecane-14-yl)-6-(2-(methylsulfonyl)pyrimidine-5-yl)hexa-5-inylamide (IIa)

[0671] [ka]

[0672] X-3b (816 mg, 1.2 mmol) was mixed with DMF (1.35 mL), III (300 mg, 90% purity, 0.6 mmol), and HCl-DMF (4 mol / L, 0.45 mL) were added, and the mixture was reacted at 30°C for 3 hours. DCM (12 mL) was added to the reaction mixture, and acetonitrile / water mixture (12 mL, v:v=30:70) was added. The mixture was separated, and the aqueous and organic phases were collected separately. The organic phase was washed with 2% sodium bicarbonate aqueous solution (12 mL), and the two aqueous phases were combined and extracted twice with DCM (12 mL x 2). The three organic phases were combined and washed sequentially with pure water (12 mL) and saturated saline solution (12 mL). The organic phase was dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated to obtain the crude product. The crude product was separated and purified by preparative HPLC to obtain 347 mg of the target product IIa formate, with a yield of 50.6%. LCMS (ESI) [M+H] + = 1098.7 1 H NMR (400 MHz, DMSO-d6) δ 9.09 (s, 2H), 8.57 (t, J = 6.6 Hz, 1H), 8.22-8.12 (m, 2H), 7.99 (d, J = 7.4 Hz, 1H), 7.91 (d, J = 8.6 Hz, 1H), 7.57 (s, 1H), 7.49 (s, 1H), 7.24 (s, 1H), 6.45 (s, 1H), 6.28 (s, 2H), 5.42 (d, J = 3.1 Hz, 2H), 5.23 (s, 2H), 4.58 (q, J = 10.2, 8.3 Hz, 2H), 4.26-4.11 (m, 2H), 3.81-3.64 (m, 2H), 3.50 (t, J = 6.1 Hz, 2H), 3.40 (s, 3H), 3.10 (t, J = 8.1 Hz, 2H), 2.54 (d, J = 7.1 Hz, 2H), 2.42-2.25 (m, 8H), 2.00-1.74 (m, 7H), 1.70-1.48 (m, 2H), 1.40-1.22 (m, 8H), 0.91-0.74 (m, 15H).

[0673] Synthesis of other Linkers and drug linker complexes Example 1: Synthesis of (S)-1-ethyl-4-(3-methyl-2-(6-(2-(methylsulfonyl)pyrimidine-5-yl)hexa-5-inylamide)butanamide)-N-(2-oxo-2-(((2,2,2-trifluoroethoxy)methyl)amino)ethyl)piperidine-4-carboxamide (L1)

[0674] [ka]

[0675] Step 1: A 3 mL solution of IV-2-1-A (495.85 mg, 2.66 mmol) in DMF was taken, and L1-1 (900 mg, 2.22 mmol) was added to it. The reaction mixture was cooled to -15°C, DMTMM (785.19 mg, 2.66 mmol) was added, and the mixture was stirred at -10°C for 2 hours. The reaction mixture was placed in DCM (200 mL), and the organic phase was washed sequentially with 2% NaHCO3 aqueous solution (100 mL x 3), water (100 mL), and saturated NaCl aqueous solution (50 mL). The organic phase was dried over anhydrous Na2SO4, filtered, and the filtrate was concentrated to obtain the crude product. The crude product was purified by silica gel column chromatography (eluent: 0-7% MeOH / DCM) to obtain the target compound L1-2 (900 mg). LCMS (ESI) [M+H] + =574.6.

[0676] Step 2: Compound L1-2 (900 mg, 1.57 mmol) was dissolved in MeOH (10 mL), Pd(OH)2 / C (270 mg) was added, and the mixture was stirred at 25°C under a hydrogen gas atmosphere and allowed to react overnight. The mixture was filtered, and the filtrate was concentrated to obtain the target compound L1-3 (620 mg). LCMS (ESI) [M+H] + = 440.2.

[0677] Step 3: At 25°C, L1-3 (200 mg, 0.45 mmol) was dissolved in DMF (2 mL), then 6-(2-(methylsulfonyl)pyrimidine-5-yl)hexa-5-ic acid (121 mg, 0.45 mmol) and DMTMM (133 mg, 0.45 mmol) were added in sequence, and the mixture was stirred and allowed to react for 1 hour. The reaction mixture was purified by preparative HPLC to obtain the target compound L1 (180 mg). LCMS (ESI) [M+H] + = 690.4. 1 H NMR (400 MHz, DMSO-d6) δ 9.11 (s, 2H), 8.43 (s, 1H), 8.37 (t, J = 6.8 Hz, 1H), 8.18-8.16 (m, 2H), 8.01 (t, J = 6.0 Hz, 1H), 4.71 (dd, J = 10.3, 7.1 Hz, 1H), 4.60 (dd, J = 10.3, 6.4 Hz, 1H), 4.07-4.11 (m, 1H), 4.03-3.95 (m, 2H), 3.76-3.57 (m, 1H), 3.41 (s, 3H), 2.77-2.67 (m, 2H), 2.58-2.50 (m, 2H), 2.41-2.26 (m, 5H), 2.19-2.03 (m, 3H), 1.99-1.89 (m, 1H), 1.90-1.70 (m, 4H), 0.99 (t, J = 7.1 Hz, 3H), 0.96-0.90 (m, 6H).

[0678] Example 2: Synthesis of (S)-2-((S)-2-(6-(2,5-dioxo-2,5-dihydro-1H-pyrrole-1-yl)hexaneamide)-3-methylbutanamide)-6-(dipropylamino)-N-(2-oxo-2-(((2,2,2-trifluoroethoxy)methyl)amino)ethyl)hexaneamide (L2)

[0679] [ka]

[0680] L2-1 (300 mg, 0.97 mmol) and X-3-1-A (531 mg, 1.07 mmol) were placed in a reaction flask, and DMF (5 mL) was added to dissolve them. DIPEA (151 mg, 1.16 mmol) was added to the mixture at room temperature, and the reaction was continued at room temperature for 3 hours. Water (50 mL) and DCM (20 mL) were added to the reaction mixture and extracted twice, and the organic phases were combined. After drying the organic phases over anhydrous Na2SO4, the mixture was filtered, and the filtrate was concentrated to 5 mL. The filtrate was purified by silica gel column chromatography (MeOH:DCM = 0-15%) to obtain the target compound L2 (300 mg). LCMS (ESI) [M+H] + =691.6; 1 H NMR (400 MHz, DMSO-d6) δ 8.82 (t, J = 6.8 Hz, 1H), 8.25 (t, J = 5.8 Hz, 1H), 8.06 (t, J = 9.9 Hz, 1H), 7.80 (t, J = 10.7 Hz, 1H), 7.03 (s, 2H), 4.75-4.65 (m, 2H), 4.31-4.22 (m, 1H), 4.13 (dd, J = 15.4, 7.3 Hz, 1H), 4.02 (q, J = 9.4 Hz, 2H), 3.82-3.71 (m, 2H), 3.40 (t, J = 7.1Hz, 2H), 3.06-2.98 (m, 6H), 2.26-2.06 (m, 2H), 2.03-1.90 (m, 1H), 1.68-1.60 (m, 8H), 1.53-1.48 (m, 3H), 1.37-1.26 (m, 3H), 1.24-1.18 (m, 2H), 0.93 (t, J = 7.3 Hz, 6H), 0.85 (t, J = 7.0 Hz, 6H).

[0681] Example 3: Synthesis of (S)-4-(2-(6-(2,5-dioxo-2,5-dihydro-1H-pyrrole-1-yl)hexaneamide)-3-methylbutanamide)-1-ethyl-N-(2-oxo-2-(((2,2,2trifluoroethoxy)methyl)amino)ethyl)piperidine-4-carboxamide (L3).

[0682] [ka]

[0683] At 25°C, L1-3 (200 mg, 0.46 mmol) was dissolved in DMF (2 mL), then L2-1 (170 mg, 0.55 mmol) and DIPEA (71 mg, 0.55 mmol) were added in sequence. After the addition was complete, the mixture was stirred at room temperature for 1 hour to allow the reaction to proceed. The reaction was monitored by LC-MS, and the reaction solution was purified by preparative high-performance liquid chromatography (acetonitrile: 0.05% FA-containing H2O = 5%~50%) to obtain the target compound INT4 (200 mg). LCMS (ESI) [M+H] + = 633.45. 1 H NMR (400 MHz, DMSO-d6) δ 8.42 (s, 1H), 8.35 (t, J = 6.8 Hz, 1H), 8.22 (s, 1H), 8.13-8.02 (m, 2H), 7.03 (s, 2H), 4.73 (dd, J = 10.3, 7.1 Hz, 1H), 4.62 (dd, J = 10.3, 6.4 Hz, 1H), 4.10-3.98 (m, 3H), 3.76-3.70 (m, 2H), 3.63-3.58 (m, 1H), 3.41-3.37 (m, 2H), 2.74- 2.71 (m, 2H), 2.36 (q, J = 7.2 Hz, 2H), 2.30-2.04 (m, 6H), 1.98-1.93 (m, 1H), 1.86-1.84 (m, 1H), 1.53-1.43 (m, 4H), 1.25-1.14 (m, 2H), 1.02 (t, J = 7.1 Hz, 3H), 0.95-0.92 (m, 6H).

[0684] Example 4: Synthesis of (S)-6-(dimethylamino)-2-((S)-3-methyl-2-(6-(4-(2-(methylsulfonyl)pyrimidine-5-yl)-1H-1,2,3-triazole-1-yl)hexanamide)butanamide)-N-(2-oxo-2-(((2,2,2-trifluoroethoxy)methyl)amino)ethyl)hexanamide (L4)

[0685] [ka]

[0686] Step 1: Compound IV-2-2-B-4 (20 g, 48.09 mmol) was dissolved in tetrahydrofuran (200 mL), and the mixture was cooled to 5°C while stirring. Sodium borohydride cyanohydride (9.07 g, 144.27 mmol) was added to the solution, and the temperature was raised to 10°C. Then, aqueous formaldehyde solution (15.61 g, 192.36 mmol) was added, and the reaction mixture was brought to room temperature and stirred for 2 hours. The reaction was monitored by HPLC, and concentrated hydrochloric acid (12 mL) and water (20 mL) were added to the reaction mixture to quench it. The mixture was then stirred overnight at 30°C. The reaction mixture was concentrated under reduced pressure until no more droplets fell, water (200 mL), dichloromethane (200 mL), and anhydrous sodium sulfate (60 g) were added, and the mixture was stirred at 40°C to dissolve. After standing, the mixture was separated, and the aqueous phase was extracted with dichloromethane (200 mL). The pH of the aqueous phase was adjusted to 7, and dichloromethane (200 mL), saturated sodium chloride aqueous solution (100 mL), and anhydrous sodium sulfate (90 g) were added in order to dissolve completely. After standing, the mixture was separated, and dichloromethane (200 mL) was added to the aqueous phase for extraction. The organic phase was combined, dried over anhydrous sodium sulfate, filtered, and the organic phase was concentrated under reduced pressure to obtain the target compound L4-2 (16 g). LCMS (ESI) [M+H] + =408.54.

[0687] Step 2: Compound L4-2 (16 g, 28.67 mmol) was dissolved in the reaction system of compound IV-2-1-A (4.85 g, 26.06 mmol), the temperature was lowered to -12°C, DMTMM (7.21 g, 26.06 mmol) was added, and the reaction was maintained at -12°C for 2 hours. The reaction was monitored by HPLC, EA (425 mL) was added to the reaction mixture, filtered, and the filtrate was washed with 2% sodium bicarbonate aqueous solution (200 mL x 2). The organic phase was concentrated under reduced pressure until no more droplets fell, and acetonitrile (30 mL) was added to the crude product. The mixture was dissolved by adding [a certain substance], then added dropwise to an aqueous solution of citric acid (12.5g, 65.15 mmol) (300mL) at 5-10°C, stirred for 30 minutes, filtered, the pH of the filtrate was adjusted to 10 with sodium carbonate, and DCM (300mL) was added for extraction. The organic phase was concentrated under reduced pressure until no more droplets were added, methyl tert-butyl ether (45mL) was added to dissolve it, and then added dropwise to n-heptane (900mL) to precipitate a large amount of solid. The mixture was filtered, and the filtered cake was dried to obtain the target compound L4-3 (4.3g). LCMS (ESI) [M+H] + = 576.38.

[0688] Step 3: Compound L4-3 (800 mg, 1.04 mmol) was dissolved in methanol (8 mL), and under nitrogen gas protection, palladium hydroxide (0.15 g, 1.04 mmol) was added. The mixture was purged three times with hydrogen gas, and the mixture was stirred overnight at room temperature under a hydrogen gas atmosphere. The reaction was monitored by LC-MS, and the reaction mixture was filtered directly. The filtrate was concentrated under reduced pressure to obtain the target compound L4-4 (460 mg). LCMS (ESI) [M+H] + =442.5.

[0689] Step 4: Compound L4-4 (460 mg, 1.05 mmol) was dissolved in DMF (5 mL), compound L4-5 (0.36 g, 1.05 mmol) was added, and the mixture was cooled to 5°C while stirring. DMTMM (0.29 g, 1.05 mmol) was added all at once, and the mixture was kept at -12°C for 2 hours. The reaction was monitored by LC-MS, and the reaction solution was directly purified by preparative high-performance liquid chromatography (acetonitrile: 0.05% FA-containing H2O = 5%~50%) to obtain the target compound L4 (400 mg). LCMS (ESI) [M+H] + =763.53. 1 H NMR (400 MHz, DMSO-d6) δ 9.48 (s, 2H), 8.94 (s, 1H), 8.76 (t, J = 6.8 Hz, 1H), 8.29-8.15 (m, 2H), 8.00 (d, J = 7.3 Hz, 1H), 7.82 (d, J = 8.7 Hz, 1H), 4.74-4.57 (m, 2H), 4.47 (t, J = 7.0 Hz, 2H), 4.24-4.09 (m, 2H), 3.99 (q, J = 9.4 Hz, 2H), 3.82-3.63 (m, 2H), 3.44 (s, 3H), 2.27-2.08 (m, 10H), 1.92 (m, 2H), 1.73-1.47 (m, 4H), 1.43-1.19 (m, 6H), 0.80 (t, J = 7.3 Hz, 6H).

[0690] Example 5: Synthesis of (S)-2-((S)-2-(2,2-dimethyl-4-(4-(2-(methylsulfonyl)pyrimidine-5-yl)-1H-1,2,3-triazole-1-yl)butanamide)-3-methylbutanamide)-6-(dimethylamino)-N-(2-oxo-2-(((2,2,2-trifluoroethoxy)methyl)amino)ethyl)hexanamide (L5)

[0691] [ka]

[0692] Compound L4-4 (300 mg, 0.68 mmol) was dissolved in DMF (5 mL), compound L5-1 (0.23 g, 0.68 mmol) was added, the temperature was lowered to -12°C, DMTMM (0.19 g, 0.68 mmol) was added, and the mixture was kept at -12°C for 1 hour. The reaction was monitored by LC-MS. The reaction solution was directly purified by preparative high-performance liquid chromatography (acetonitrile: 0.05% FA-containing H2O = 5%~50%) to obtain the target compound L5 (170 mg). LCMS (ESI) [M+H] + =763.55. 1 H NMR (400 MHz, DMSO-d6) δ 9.51 (s, 2H), 8.97 (s, 1H), 8.81 (t, J = 6.9 Hz, 1H), 8.32 (t, J = 5.9 Hz, 1H), 8.24 (s, 1H), 8.05 (d, J = 7.3 Hz, 1H), 7.45 (d, J = 8.5 Hz, 1H), 4.68 (m, 2H), 4.51 - 4.38 (m, 2H), 4.29 (q, J = 7.2 Hz, 1H), 4.17 (t, J = 8.2 Hz, 1H), 4.01 (q, J = 9.4 Hz, 2H), 3.75 (t, J = 5.0 Hz, 2H), 3.47 (s, 3H), 2.29-2.01 (m, 10H), 1.78-1.51 (m, 2H), 1.46-1.18 (m, 10H), 0.90 (t, J = 6.7 Hz, 6H).

[0693] Example 6: Synthesis of (S)-N-(10-benzyl-1,1,1-trifluoro-6,9,12,15-tetraoxo-3-oxa-5,8,11,14-tetraazahexadecane-16-yl)-6-(2,5-dioxo-2,5-dihydro-1H-pyrrole-1-yl)hexanamide (L6)

[0694] [ka]

[0695] Step 1: Compound L6-1 (225.22 mg, 1.21 mmol) was weighed and added to a necked flask. Anhydrous DMF (5 mL) was added, and the mixture was stirred at room temperature for 5 minutes. After clarification, compound IV-2-1-A (500 mg, 1.21 mmol) was added, and the mixture was stirred at room temperature for 5 minutes. Then, the temperature was lowered to -10°C and stirred for 5 minutes. DMTMM (392.25 mg, 1.33 mmol) was added to the reaction mixture, and the reaction was continued at -10°C for 1 hour. The reaction was monitored by LC-MS. Add DCM (30 mL) to the reaction mixture and dissolve it. Add saturated NaHCO3 (30 mL) aqueous solution and stir for 5 minutes. Allow to stand and separate the liquid and aqueous phases. Re-extract the aqueous phase with DCM (20 mL), combine with the organic phase, wash the organic phase with water (50 mL), concentrate under reduced pressure to 10 mL, and then purify directly by wet column chromatography (MeOH:DCM = 0-10%) to obtain the target compound L6-2 (300 mg). LCMS (ESI) [M+Na] + =604.28.

[0696] Step 2: Compound L6-2 (300 mg, 0.52 mmol) was dissolved in methanol (10 mL), and Pd / C (73.02 mg, 0.052 mmol) was added under nitrogen gas protection. After three purgings with hydrogen gas, the mixture was reacted overnight under a hydrogen gas atmosphere, and the reaction was monitored by LC-MS. The reaction mixture was filtered, and the filtrate was concentrated under reduced pressure to obtain the target compound L6-3 (210 mg). LCMS (ESI) [M+H] + =448.28.

[0697] Step 3: Compound L6-3 (210 mg, 0.47 mmol) and DIPEA (72.89 mg, 0.56 mmol) were dissolved in DMF (2 mL), L2-1 (144.9 mg, 0.47 mmol) was added, and the mixture was stirred at room temperature for 3 hours. The reaction was monitored by LC-MS. The reaction solution was directly purified by preparative high-performance liquid chromatography (acetonitrile: 0.05% FA-containing H2O = 5%~50%) to obtain the target compound L6 (200 mg). LCMS (ESI) [M+Na] + =663.41. 1 H NMR (400 MHz, DMSO-d6) δ 8.71 (t, J = 6.7 Hz, 1H), 8.33 (t, J = 5.8 Hz, 1H), 8.14 (d, J = 8.0 Hz, 1H), 8.08 (t, J = 5.5 Hz, 1H), 8.01 (t, J = 5.5 Hz, 1H), 7.31-7.18 (m, 5H), 7.02 (s, 2H), 4.71 (d, J = 6.8 Hz, 2H), 4.56-4.50 (m, 1H), 4.04 (q, J = 9.4 Hz, 2H), 3.83-3.59 (m, 6H), 3.40 (t, J = 7.1 Hz, 2H), 3.12-3.06 (m, 1H), 2.88-2.80 (m, 1H), 2.14 (t, J = 7.4 Hz, 2H), 1.57-1.45 (m, 4H), 1.28-1.18 (m, 2H).

[0698] Example 7: Synthesis of (S)-2-((S)-2-(6-(2,5-dioxo-2,5-dihydro-1H-pyrrole-1-yl)hexaneamide)-3-methylbutanamide)-6-(dipropylamino)-N-(2-(((3-((S)-7-ethyl-7-hydroxy-8,11-dioxo-7,8,11,13-tetrahydro-10H-[1,3]dioxolo[4,5-g]pyrano[3',4':6,7]indolidino[1,2-b]quinoline-14-yl)propoxy)methyl)amino)-2-oxoethyl)hexaneamide (IIb)

[0699] [ka]

[0700] Compound L2 (10 mg, 0.022 mmol) and Compound III (30 mg, 0.044 mmol) were dissolved in DMF (0.2 mL), and HCl / DMF (1 N, 0.11 mL) was added. The reaction mixture was stirred at room temperature and allowed to react for 3 hours. The reaction mixture was directly purified by preparative high-performance liquid chromatography to obtain the target compound IIb (8 mg). LCMS (ESI) [M / 2+H] + =521.7; 1 H NMR (400 MHz, DMSO-d6) δ 8.59 (t, J = 6.4 Hz, 1H), 8.23 ​​(s, 1H), 8.17 (t, J = 5.7 Hz, 1H), 7.95 (t, J = 8.0 Hz, 1H), 7.81 (d, J = 8.5 Hz, 1H), 7.61 (s, 1H), 7.53 (s, 1H), 7.27 (s, 1H), 7.01 (s, 2H), 6.50 (s, 1H), 6.31 (s, 2H), 5.50 - 5.40 (m, 2H), 5.26 (s, 2H), 4.66-4.60 (m, 2H), 4.22 (dd, J = 13.4, 7.5 Hz, 1H), 4.14 (t, J = 7.8 Hz, 1H), 3.80-3.70 (m, 3H), 3.54- 3.51 (m, 2H), 3.16 - 3.11 (m, 2H), 2.38 - 2.32 (m, 6H), 2.22 - 2.06 (m, 2H), 1.98 - 1.85 (m, 5H), 1.72- 1.65 (m, 1H), 1.55- 1.52 (m, 1H), 1.51-1.45 (m, 4H), 1.40 - 1.35 (m, 7H), 1.29 - 1.17 (m, 4H), 0.90 (t, J = 7.3 Hz, 3H), 0.84- 0.80 (m, 12H).

[0701] ADC preparation Example 1: Preparation of ADC-01 After codon optimization and gene synthesis (Shanghai Biotechnology Co., Ltd.) of the heavy chain amino acid sequence (SEQ ID NO: 1) of 2E3-02, it was constructed in a PTT5 vector and named PPT5-02-CH. After codon optimization and gene synthesis (Shanghai Biotechnology Co., Ltd.) of the light chain amino acid sequence (SEQ ID NO: 2) of 2E3-02, it was constructed in a PTT5 vector and named PTT5-02-CL. The anti-B7H3 antibody expression plasmids PTT5-02-CH / PTT5-02-CL were simultaneously transfected into HEK293F cells (ATCC) using PEI max reagent, and expressed in a 5% CO2 shaker at 37°C for 7 days. The supernatant was collected and purified using ProA magnetic beads to obtain the anti-B7H3 antibody 2E3-02 (whose heavy chain sequence is SEQ ID NO: 1 and light chain sequence is SEQ ID NO: 2).

[0702] 25 mL of 2E3-02 antibody (anti-B7H3, concentration 28.5 mg / mL, 20 mM acetate buffer) was taken, diluted with 25 mL of 20 mM acetate buffer, then 1 mL of aqueous solution containing 0.25 M EDTA was added and mixed uniformly. The pH of the sample was adjusted to 7.6 with 0.5 M disodium hydrogen phosphate aqueous solution, then 4.5 equivalents of 20 mM TCEP (tris(2-carboxyethyl)phosphine hydrochloride) solution were added and mixed uniformly, and the reaction was allowed to proceed at room temperature for 90 minutes. Finally, 10 equivalents of IIa dissolved in DMSO were added and mixed uniformly, and the reaction was continued at room temperature for 2 hours. After the reaction was complete, the sample was replaced with 10 mM histidine buffer at pH 5.5 using a 30 kDa ultrafiltration tube to remove low molecular weight substances. Finally, the sample was concentrated to obtain a solution containing the anti-B7H3 antibody ADC composition (ADC-01), and the DAR value was measured to be 7.98 by mass spectrometry.

[0703] [ka]

[0704] In the formula, Ab is the B7H3 antibody 2E3-02.

[0705] The method for measuring the DAR value is as follows: Chromatography conditions: Column: PLRP-S, 2.1 × 50 mm, 5 μm, Mobile phase A: 0.1% FA / H2O, Mobile phase B: 0.1% FA / ACN Column temperature: 30°C, Sample chamber temperature: 8°C, Flow rate: 0.6 mL / min, Injection volume: 2 μL

[0706] [Table 8]

[0707] Sample preparation: 50 μg of ADC-01 sample was taken, 2 μL of 1 M DTT was added, and ultrapure water was added up to 50 μL to dilute to a concentration of approximately 1.0 mg / mL. The mixture was homogenized and reduced at room temperature for 30 minutes. LC / MS model: Agilent 1290-6545XT Q-TOF. Mass spectrometry conditions: Gas temp: 320℃, Drying Gas: Nebulizer: 35psi, Sheath Gas Temp: 350℃, Sheath Gas Flow: 11L / min, m / z500~3000. The detection results are shown below.

[0708] [Table 9]

[0709] In the table, mAb represents an uncoupled antibody, LC represents the antibody light chain, HC represents the antibody heavy chain, DAR1 represents a complex containing a light or heavy chain coupled with one toxin molecule, DAR2 represents a complex containing a light or heavy chain coupled with two toxin molecules, and DAR3 represents a complex containing a light or heavy chain coupled with three toxin molecules. Of these, the theoretical molecular weight of monoclonal antibodies is calculated using the G0F glycan form. The explanations of mAb, LC, HC, DAR1, DAR2, and DAR3 below are as described above.

[0710] Measurements revealed that the light chain of the 2E3-02 antibody coupled with 0-1 toxin molecules (LC and DAR1 ratios were 1.0% and 99.0%, respectively), while the heavy chain coupled with 0-3 toxin molecules (mAb, DAR1, DAR2, and DAR3 ratios were 0%, 0%, 0%, and 100%, respectively). Based on these results, the antibody-drug binding ratio (DAR value) of ADC-01 was calculated as 7.98.

[0711] ADC Bioactivity Test Example 1: Efficacy study of ADC against NCI-HT29 transplanted tumors 1. Experimental materials Test compound: ADC-01 Experimental cells: NCI-HT29 cells purchased from ATCC. Laboratory animals: Balb / c nu nude mice, female, 5-6 weeks old, purchased from Victoria Laboratory Animals Co., Ltd.

[0712] 2. Experimental Design 2.1. Cell Processing NCI-HT29 cells were cultured in 1640 medium containing 10% FBS in a 15cm diameter culture dish. After reaching approximately 80-90% fusion, they were digested with trypsin-EDTA, washed twice with PBS, centrifuged, resuspended in pre-cooled PBS, counted using a cell counter, and diluted with PBS to a cell concentration of 5 × 10⁶. 7 The value was set to / mL.

[0713] 2.2 Tumor cell transplantation Balb / c nu mice were acclimated to the laboratory environment for 2-5 days, and NCI-HT29 cells were administered in 5 × 10⁶ cells. 6 The cell inoculation dose was 0.2 mL (containing 50% Matrigel) per animal, administered subcutaneously to the right rib, and the tumor was 250 mm. 3 The experiment was conducted when the plants had grown to a certain extent.

[0714] 2.3. Animal Administration and Detection The tumor-bearing nude mice in the group were administered according to the following plan:

[0715] [Table 10]

[0716] After the completion of the administration cycle, observation was continued for 1-2 weeks. After the final tumor volume measurement, the tumor was isolated, its weight was accurately measured, and photographs were taken for recording.

[0717] 2.4. Measurement of tumor volume and body weight: Tumor volume and body weight were measured twice a week, and the TGI% was calculated. Tumor volume (V) calculation formula: V = 1 / 2 × L 長 ×L 短 2 .

[0718] 3. Experimental Results Table 1. NCI-HT29 transplanted tumor model data (tumor volume mm) 3 )

[0719] [Table 11]

[0720] Conclusion: As shown in Table 1, the ADC of this application has an extremely strong tumor inhibitory effect. During administration, there was no significant weight loss or significant drug toxicity in any of the animal groups.

[0721] The present invention is not limited to the specific embodiments described herein. The present invention extends to any new features or combinations disclosed herein, as well as any new methods or process steps or combinations disclosed herein. (Note) The inventions disclosed herein include the following embodiments. <Item 1> A method for preparing a compound of formula II or a salt thereof, comprising step i) reacting a compound of formula III or a salt thereof with a compound of formula X-3 or a salt thereof to obtain a compound of formula II or a salt thereof, [ka] In the formula, L 1 teeth,

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Claims

1. A method for preparing a compound of formula II or a salt thereof, comprising step i) reacting a compound of formula III or a salt thereof with a compound of formula X-3 or a salt thereof to obtain a compound of formula II or a salt thereof, 【Chemistry 1】 In the ceremony, L １ teeth, 【Chemistry 2】 Selected from, the 1st place is linked to Lg, and the 2nd place is L ２ Connect to, Lg is MeSO ２ - and L ２ teeth 【Transformation 3】 The winner was selected from the group, and the first place went to L. １ L is linked to 2nd place. ３ Connect to, n4 is selected from any integer between 0 and 10. Y is -CH ２ -, -OCH ２ CH ２ - and is selected from Z is CR ｍ R ｎ , NR ｍ Selected from, R ｍ , R ｎ Each of these is independently selected from H, deuterium, C1-4 alkyl groups, C2-4 alkenyl groups, C2-4 alkynyl groups, C3-6 cycloalkyl groups, and 3-6 membered heterocyclic groups. Or, R ｍ and R ｎ These, together with the carbon atoms linked to them, form a 3-6 membered carbon ring or a 3-6 membered heterocycle. L ３ は、Val-Ala、AA １ -Val-Ala、Oal-AA １ -Gly、Ala-AA １ -Gly、Gly-AA １ -Gly、Val-AA １ -Ala、Oal-AA １ -Val、Ala-AA １ -Ala、Ala-AA １ -Val、Gly-AA １ -Ala、Gly-AA １ - Selected from AA １ The structure of the amino acid residue shown is as follows: 【Chemistry 4】 During the ceremony, R ａ , R ｂ H and 【Transformation 5】 Selected from and R ａ , R ｂ It is not H at the same time, Or, R ａ and R ｂ These, together with the carbon atoms linked to them, form a 4- to 10-membered heterocycle, and the 4- to 10-membered heterocycle can optionally have one or more R ０ Replaced by, r is 0, and r １ It is 4, R ｍ１ , R ｎ１ Each of these is independently selected from H, C1-6 alkyl groups, and C3-6 cycloalkyl groups. Or, R ｍ１ and R ｎ１ These, together with the nitrogen atoms linked to them, form a 4- to 10-membered heterocycle, and the 4- to 10-membered heterocycle can optionally have one or more R atoms. ０’ Replaced by, R ０ , R ０’ These are, independently, C1-6 alkyl groups, C3-6 cycloalkyl groups, and -NR ｍ２ R ｎ２ and optionally selected from 4-10 membered heterocyclic groups substituted with C1-6 alkyl groups, R ｍ２ , R ｎ２ Each is independently selected from H and C1-6 alkyl groups, R ８ R is selected from hydrogen, C1-30 alkyl groups, C3-7 cycloalkyl groups, 3-20 membered heterocyclic groups, C1-6 alkyl groups-C3-6 cycloalkyl groups, C1-6 alkyl groups-4-6 membered heterocyclic groups, C1-6 alkyl groups-C5-10 heteroaryl groups, and C1-6 alkyl groups-C6-10 aryl groups, and the alkyl groups, cycloalkyl groups, heterocyclic groups, and aryl groups are optionally selected as one or more R groups. ｘ Replaced by, R ｘ A method for preparing a compound of formula II or a salt thereof, characterized in that the group is selected from hydrogen, deuterium, fluorine, chlorine, bromine, methyl group, methoxy group, amino group, dimethylamino group, nitro group, cyano group, and azide group.

2. (1) L １ teeth, 【Transformation 6】 Selected from, the 1st place is linked to Lg, and the 2nd place is L ２ Connect to, (2) Y is -CH ２ - and (3) n4 is selected from 0, 1, 2, 3, (4) Z is -CH ２ -, -C(CH ３ ) ２ -, -N(CH ３ ) - and -NH- are selected, (5) Note ｍ , R ｎ Each of these is independently selected from H, C1-4 alkyl groups, C2-4 alkenyl groups, C2-4 alkynyl groups, C3-6 cycloalkyl groups, and 3-6 membered heterocyclic groups, or R ｍ and R ｎ These, together with the carbon atoms linked to them, form a 3-6 membered carbon ring or a 3-6 membered heterocycle. (6) L ３ Val-AA １ -Gly, Ala-AA １ -Gly, Gly-AA １ -Gly, Val-AA １ -Ala, Val-AA １ -Val, Ala-AA １ -Ala,Ala-AA １ -Val, Gly-AA １ -Ala, Gly-AA １ - Selected from Val, Ala-Ala-Ala, Ala-Ala-Asn, and Gly-Gly-Phe-Gly, (7) R ａ , R ｂ One of them is H, and the other is 【Transformation 7】 And, or, R ａ and R ｂ Together with the carbon atoms bonded to them, R ０ It forms a 5-6 member heterocycle substituted with, (8) R ｍ１ , R ｎ１ Each is independently selected from H and C1-6 alkyl groups, or R ｍ１ and R ｎ１ These, together with the nitrogen atoms bonded to them, optionally form R ０’ It forms a 5-6 member heterocycle substituted with, (9) Caution ０ , R ０’ These are, independently, C1-6 alkyl groups and -NR ｍ２ R ｎ２ and optionally selected from 5-6 membered heterocyclic groups substituted with C1-6 alkyl groups, (10) R ｍ２ , R ｎ２ It is a methyl group, (11) R ８ is selected from hydrogen, a C1-30 alkyl group, and a C1-6 alkyl group-C6-10 aryl group, and the alkyl group and aryl group are optionally substituted with one or more Rs ｘ and R ｘ is selected from hydrogen, fluorine, a methyl group, and a methoxy group A feature that satisfies one or more of the following conditions: A method for preparing the compound of formula II or a salt thereof as described in claim 1.

3. (1) L1 is 【Transformation 8】 The first place is linked to Lg, and the second place is linked to L2. (2) R m and R n are each independently selected from H and Me, (3) L3 is Val-AA1-Gly, (4) Either Ra a or R b is H, and the other is 【Chemistry 9】 And, or, Ra and Rb together with the carbon atoms bonded to them, 【Chemistry 10】 It forms, and the first carbon atom is a carbon atom that is bonded together with Ra and Rb. (5) R m1 and R n1 are each independently selected from H, a methyl group, an ethyl group, an n-propyl group, and an n-butyl group, or R m1 and R n1 together with the nitrogen atom linked to them, 【Chemistry 11】 It forms a structure, and the first nitrogen atom is a nitrogen atom that is bonded to both R m1 and R n1. (6) R0 is a methyl group, an ethyl group, and 【Chemistry 12】 Selected from, R 0' is selected from a methyl group and -NR m2 R n2, (7) R 8 is selected from hydrogen, methyl group, ethyl group, isopropyl group, tert-butyl group, 2,2,2-trifluoroethyl, 2,2,3,3,3-pentafluoro-1-propyl, and benzyl group. A feature that satisfies one or more of the following conditions: A method for preparing the compound of formula II or a salt thereof as described in claim 2.

4. (1) L １ -L ２ but 【Chemistry 13】 If selected from, the 1st place is linked to Lg, and the 2nd place is linked to L ３ Connect to, (2) L ３ teeth, 【Chemistry 14】 The winner was selected from the group, and the first place went to L. ２ It connects to NH, and the second place connects to NH. A feature that satisfies one or more of the following conditions: A method for preparing the compound of formula II or a salt thereof as described in claim 1.

5. (1) L1 - L2 is 【Chemistry 15】 Selected from, the 1st place is linked to Lg, the 2nd place is linked to L3, (2) L3 is, 【Chemistry 16】 The first place is linked to L2, and the second place is linked to NH. A feature that satisfies one or more of the following conditions: A method for preparing the compound of formula II or a salt thereof as described in claim 4.

6. (1) In step i), the compound of formula III or a salt thereof is reacted with the compound of formula X-3 or a salt thereof after azeotropic dehydration to obtain the compound of formula II or a salt thereof. (2) In step i), the compound of formula III or a salt thereof is reacted with the compound of formula X-3 or a salt thereof under conditions without the addition of acid to obtain the compound of formula II or a salt thereof, and the reaction temperature is selected from 110 to 150°C. (3) In step i), the compound of formula III or a salt thereof is reacted with the compound of formula X-3 or a salt thereof under acidic conditions to obtain the compound of formula II or a salt thereof, and the reaction temperature is selected from 0 to 80°C. (4) In step i), the acid under the acidic conditions is a protonic acid or an aprotonic acid, and in step i), the molar ratio of the compound of formula III or its salt to the compound of formula X-3 or its salt is selected from 1:1 to 1:

5. (5) In step i), the reaction solvent is selected from one of the following: ether solvents, nitrile solvents, amide solvents, sulfone solvents, or water, or any combination thereof. A feature that satisfies one of the conditions, A method for preparing the compound of formula II or a salt thereof as described in claim 1.

7. (1) In step i), the azeotropic solvent is selected from toluene, xylene, chloroform, acetonitrile, ethyl acetate, and dichloroethane. (2) In step i), the compound of formula III or a salt thereof is reacted with the compound of formula X-3 or a salt thereof under conditions without the addition of acid to obtain the compound of formula II or a salt thereof, and the reaction temperature is selected from 120 to 130°C. (3) In step i), the compound of formula III or a salt thereof is reacted with the compound of formula X-3 or a salt thereof under acidic conditions to obtain the compound of formula II or a salt thereof, and the reaction temperature is selected from 20 to 35°C. (4) In step i), the compound of formula III or a salt thereof is reacted with the compound of formula X-3 or a salt thereof under acidic conditions to obtain the compound of formula II or a salt thereof. The acid under the acidic conditions is selected from hydrogen chloride, hydrobromic acid, sulfuric acid, boron trifluoride diethyl ether, p-toluenesulfonic acid, pyridinium salt of p-toluenesulfonate, zinc acetate, aluminum trichloride (AlCl3), ferric chloride (FeCl3), ytterbium trifluoromethanesulfonate (Yb(OTf)3), triethylamine hydrochloride, boron trifluoride acetonitrile, boron trifluoride tetrahydrofuran, pyridine hydrogen chloride, and pyridine hydrogen bromide. (5) In step i), the compound of formula III or a salt thereof is reacted with the compound of formula X-3 or a salt thereof under acidic conditions to obtain the compound of formula II or a salt thereof, and the molar ratio of the compound of formula III or a salt thereof to the acid selected for the reaction under acidic conditions is selected from 1:0.2 to 1:

6. (6) In step i), the molar ratio of the compound of formula III or its salt to the compound of formula X-3 or its salt is selected from 1:2 to 1:

3. (7) In step i), the reaction solvent is N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), N-methylpyrrolidone (NMP), or dimethyl sulfoxide (DMSO), and the mass volume ratio (g / mL) of the compound of formula III or its salt to the selected solvent is selected from 1:2 to 1:

10. A feature that satisfies one of the conditions, A method for preparing the compound of formula II or a salt thereof as described in claim 6.

8. A method for preparing the compound of formula II or a salt thereof is: Protecting group PG on amino group from compound of formula IV-2 or its salt ２ Step m-1) removes the compound of formula X-3-1 or a salt thereof, 【Chemistry 17】 A method for preparing a compound of formula X-3 or a salt thereof further comprises step m-2) a condensation reaction between a compound of formula X-3-1 or a salt thereof and a compound of formula X-1, wherein the condensation reaction of the compound of formula X-3-1 or a salt thereof is obtained to obtain a compound of formula X-3 or a salt thereof. [Chemistry 18] In the formula, E is selected from a hydroxyl group, a halogen, or an activated hydroxyl group. PG ２ is selected from amino protecting groups, Lg, L １ , L ２ , L ３ , R ８ The definition is as described in claim 1, A method for preparing the compound of formula II or a salt thereof as described in claim 1.

9. (1) E is a hydroxyl group, chlorine, bromine, 【Chemistry 19】 Selected from, (2) PG2 is selected from benzyloxycarbonyl group (Cbz), tert-butoxycarbonyl group (Boc), 9-fluorenylmethoxycarbonyl group (Fmoc), allyloxycarbonyl group (Alloc), trimethylsilylethoxycarbonyl group (Teoc), methoxycarbonyl group and ethoxycarbonyl group. A feature that satisfies one or more of the following conditions: A method for preparing the compound of formula II or a salt thereof as described in claim 8.

10. (1) In step m-1), removal is performed under acidic conditions, wherein the acid under acidic conditions includes protic acids and aprotic acids; or removal is performed under basic conditions, wherein the base under basic conditions includes organic bases and inorganic bases; or removal is performed under metallic reagent conditions, wherein the metallic reagent is selected from palladium-based reagents or platinum-based reagents. (2) In step m-1), the PG ２ When is a 9-fluorenylmethoxycarbonyl group (Fmoc), the reaction solvent is selected from DMF, dichloromethane, tetrahydrofuran, and 1,4-dioxane, and the mass-volume ratio (g / mL) of the compound of formula IV-2 or its salt to the selected reaction solvent is selected from 1:5 to 1:

50. (3) In step m-1), the PG ２ When is a 9-fluorenylmethoxycarbonyl group (Fmoc), the reaction temperature is selected from 0 to 50°C. (4) In step m-1), the PG ２ When is a benzyloxycarbonyl group (Cbz), the reaction temperature is 0°C to 100°C. (5) In step m-1), the PG ２ When is a benzyloxycarbonyl group (Cbz), the reaction solvent is selected from any one of alcohols, ethers, esters, amides, or water, or a mixture of them in any proportion, and the mass-volume ratio (g / mL) of the compound of formula IV-2 or its salt to the selected reaction solvent is selected from 1:3 to 1:

50. (6) In step m-2), a compound of formula X-3 or a salt thereof is obtained by a condensation reaction between the compound of formula X-3-1 or a salt thereof, (7) In step m-2), if E is a hydroxyl group, the reaction occurs under the action of a condensing agent, under basic or neutral conditions. The condensing agent is selected from DMTMM, HATU, HBTU, COMU, and N-ethynyl-N-methylmethanesulfonamide. The base in the aforementioned basic conditions is selected from organic bases or inorganic bases. The molar ratio of the compound of formula X-1 or its salt to the condensing agent is selected from 1:1 to 1:

5. (8) In step m-2), if E is a hydroxyl group, the molar ratio of the compound of formula X-3-1 or its salt to the compound of formula X-1 or its salt is selected from 1:0.9 to 1:1.

2. (9) In step m-2), if E is a hydroxyl group, the reaction solvent is selected from one of DMF, acetonitrile, tetrahydrofuran, methanol, dichloromethane, and water, or any combination thereof. (10) In step m-2), if E is a hydroxyl group, the reaction temperature is selected from -20 to 100°C. (11) In step m-2), if E is selected from halogens, the compound of formula X-3-1 or a salt thereof and the compound of formula X-1 or a salt thereof react under basic conditions. (12) In step m-2), if E is a halogen, the molar ratio of the compound of formula X-1 or its salt to the compound of formula X-3-1 or its salt is selected from 1:0.8 to 1:2.

0. (13) In step m-2), if E is a halogen, the reaction solvent is selected from one or any combination of DMF, tetrahydrofuran, dichloromethane, and acetonitrile, and the mass-volume ratio (g / mL) of the compound of formula X-1 or its salt to the selected reaction solvent is selected from 1:2 to 1:

50. (14) In step m-2), if E is a halogen, the reaction temperature is selected from -20 to 100°C. A feature that satisfies one or more of the following conditions: A method for preparing the compound of formula II or a salt thereof as described in claim 8.

11. (1) In step m-1), if PG2 is a 9-fluorenylmethoxycarbonyl group (Fmoc), the protecting group PG2 is removed from the compound of formula IV-2 or its salt under basic conditions, the base under basic conditions is selected from piperidine, diethylamine, morpholine, and DBU, and the molar ratio of the compound of formula IV-2 or its salt to the selected base is selected from 1:0.2 to 1:

40. (2) In step m-1), if PG2 is a benzyloxycarbonyl group (Cbz), the protecting group PG2 is removed from the compound of formula IV-2 or its salt under a metal reagent-hydrogen system, the metal reagent being selected from palladium carbon, platinum carbon, platinum dioxide, and palladium hydroxide, the mass ratio of the compound of formula IV-2 to the metal reagent being selected from 1:0.01 to 1, and the hydrogen gas used being 1 atm to 50 atm. (3) In step m-1), if PG2 is a 9-fluorenylmethoxycarbonyl group (Fmoc), the mass volume ratio (g / mL) of the compound of formula IV-2 or its salt to the selected reaction solvent is selected from 1:6 to 1:

20. (4) In step m-1), if the PG2 is a 9-fluorenylmethoxycarbonyl group (Fmoc), the reaction temperature is selected from 15 to 30°C. (5) In step m-1), if the PG2 is a benzyloxycarbonyl group (Cbz), the reaction temperature is selected from 20°C to 70°C. (6) In step m-1), if PG2 is a benzyloxycarbonyl group (Cbz), the reaction solvent is selected from methanol, ethanol, tetrahydrofuran, ethyl acetate, DMF, DMAc, NMP, or water, and the mass volume ratio (g / mL) of the compound of formula IV-2 or its salt to the selected reaction solvent is selected from 1:10 to 1:

30. (7) In step m-2), if E is a hydroxyl group, the reaction occurs under the action of a condensing agent, under basic or neutral conditions. The base in the above basic conditions is selected from triethylamine, N,N-diisopropylethylamine, and N-methylmorpholine. The molar ratio of the compound of formula X-1 or its salt to the condensing agent is selected from 1:1 to 1:1.

5. (8) In step m-2), if E is a hydroxyl group, the reaction temperature is selected from -20 to 30°C. (9) In step m-2), if E is selected from chlorine, fluorine, and bromine, the compound of formula X-3-1 or its salt and the compound of formula X-1 or its salt react under basic conditions. The base in the above basic conditions is selected from triethylamine, N,N-diisopropylethylamine, DBU, and N-methylmorpholine. The molar ratio of the compound of formula X-1 or its salt to the base used in the reaction is selected from 1:0.1 to 1:

5. (10) In step m-2), if E is selected from chlorine, fluorine, and bromine, the molar ratio of the compound of formula X-1 or its salt to the compound of formula X-3-1 or its salt is selected from 1:0.9 to 1:1.

2. (11) In step m-2), if E is selected from chlorine, fluorine, and bromine, the reaction solvent is acetonitrile, and the mass volume ratio (g / mL) of the compound of formula X-1 or its salt to the selected reaction solvent is selected from 1:3 to 1:

10. (12) In step m-2), if E is selected from chlorine, fluorine, and bromine, the reaction temperature is selected from 0 to 30°C. A feature that satisfies one or more of the following conditions: A method for preparing the compound of formula II or a salt thereof as described in claim 10.

12. The method for preparing the compound of formula X-3 or its salt is as follows: R ８ If it is not H, Protecting group PG on amino group from compound of formula IV-1 or its salt １ Step k-1) removes the compound of formula IV-2-1 or a salt thereof, 【Chemistry 20】 A method for preparing a compound of formula IV-2 or a salt thereof, further comprising step k-2) a condensation reaction between a compound of formula IV-2-1 or a salt thereof and a compound of formula IV-2-2 or a salt thereof, 【Chemistry 21】 PG ２ -L ３ That is, PG2-L ３－２ -L ３－１ And, During the ceremony, L ３－１ is selected from amino acid residues, and the amino acid residues are 【Chemistry 22】 The winner was selected from the group, and the first place went to L. ３－２ It was linked to , and in second place it was linked to NH, PG １ It is selected from amino protecting groups, L ３－２ is Val, Val-AA １ Ala-AA １ Gly-AA １ ,Ala-Ala,AA １ - Selected from Val, Gly-Gly-Val and Gly-Gly-Phe, L ３ , R ８ , E and PG ２ The definition is as described in claim 8, A method for preparing the compound of formula II or a salt thereof as described in claim 8.

13. (1) L3-1 is selected from amino acid residues, and the amino acid residues are 【Chemistry 23】 Selected from, the 1st place team is linked to L 3-2, the 2nd place team is linked to NH, (2) PG 1 is selected from benzyloxycarbonyl group (Cbz), tert-butoxycarbonyl group (Boc), 9-fluorenylmethoxycarbonyl group (Fmoc), allyloxycarbonyl group (Alloc), trimethylsilylethoxycarbonyl group (Teoc), methoxycarbonyl group or ethoxycarbonyl group, (3) L 3-2 is, 【Chemistry 24】 Selected from the options, the 1st place winner connects to L2, and the 2nd place winner connects to L3-1. A feature that satisfies one or more of the following conditions: A method for preparing the compound of formula II or a salt thereof as described in claim 12.

14. (1) In step k-1), removal is performed under acidic conditions, wherein the acid under acidic conditions includes protic acids and aprotic acids; or removal is performed under basic conditions, wherein the base under basic conditions includes organic bases and inorganic bases; or removal is performed under metallic reagent conditions, wherein the metallic reagent is selected from palladium-based reagents or platinum-based reagents. (2) In step k-1), the PG １ When is a 9-fluorenylmethoxycarbonyl group (Fmoc), the reaction solvent is selected from one of DMF, DMAc, NMP, dichloromethane, tetrahydrofuran, 1,4-dioxane, and acetonitrile, or any combination thereof, and the mass-volume ratio (g / mL) of the compound of formula IV-1 or its salt to the selected reaction solvent is selected from 1:5 to 1:

50. (3) In step k-1), the PG １ When is a 9-fluorenylmethoxycarbonyl group (Fmoc), the reaction temperature is selected from 0 to 50°C. (4) In step k-1), the PG １ When is a benzyloxycarbonyl group (Cbz), the reaction temperature is selected from 0°C to 100°C. (5) In step k-1), the PG １ When is a benzyloxycarbonyl group (Cbz), the reaction solvent is selected from any one of alcohols, ethers, esters, amides, or water, or a mixture of them in any proportion, and the mass-volume ratio (g / mL) of the compound of formula IV-1 or its salt to the selected reaction solvent is selected from 1:3 to 1:

20. (6) In step k-2), if E is a hydroxyl group, the reaction proceeds under basic or neutral conditions under the action of a condensing agent and / or a racemization inhibitor. The aforementioned condensing agents are DMTMM, HATU, HBTU, EDCI, COMU, N-ethynyl-N-methylmethanesulfonamide, EEDQ, and T ３ Selected from P, The racemization inhibitor is selected from HOAt and HOBt. The base in the above basic conditions is selected from DBU, triethylamine, N,N-diisopropylethylamine, and N-methylmorpholine. The molar ratio of the compound of formula IV-2-2 or its salt to the condensing agent is selected from 1:1 to 1:

5. (7) In step k-2), if E is a hydroxyl group, the molar ratio of the compound of formula IV-2-1 or its salt to the compound of formula IV-2-2 or its salt is selected from 1:0.8 to 1:

3. (8) In step k-2), if E is a hydroxyl group, the reaction solvent is selected from one of DMF, acetonitrile, tetrahydrofuran, methanol, dichloromethane, and water, or any combination thereof, and the mass volume ratio (g / mL) of the compound of formula IV-2-1 or its salt to the selected reaction solvent is selected from 1:5 to 1:

20. (9) In step k-2), if E is a hydroxyl group, the reaction temperature is selected from -20 to 100°C. A feature that satisfies one or more of the following conditions: A method for preparing the compound of formula II or a salt thereof as described in claim 12.

15. (1) In step k-1), if PG 1 is a 9-fluorenylmethoxycarbonyl group (Fmoc), the protecting group PG 1 is removed from the compound of formula IV-1 or a salt thereof under basic conditions, the base under basic conditions is selected from piperidine, diethylamine, morpholine, diisopropylamine, DBU, triethylamine and N,N-diisopropylethylamine, and the molar ratio of the compound of formula IV-1 or a salt thereof to the selected base is selected from 1:0.2 to 1:

40. (2) In step k-1), if PG 1 is a benzyloxycarbonyl group (Cbz), the protecting group PG 1 is removed from the compound of formula IV-1 or its salt under a metal reagent-hydrogen system, the metal reagent is selected from palladium carbon, platinum carbon, platinum dioxide and palladium hydroxide, the mass ratio of the compound of formula IV-1 to the metal reagent is selected from 1:0.01 to 1, and the hydrogen gas used is 1 atm to 50 atm. (3) In step k-1), if PG 1 is a 9-fluorenylmethoxycarbonyl group (Fmoc), the reaction solvent is selected from DMF or tetrahydrofuran, and the mass volume ratio (g / mL) of the compound of formula IV-1 or its salt to the selected reaction solvent is selected from 1:6 to 1:

20. (4) In step k-1), if PG 1 is a 9-fluorenylmethoxycarbonyl group (Fmoc), the reaction temperature is selected from 15 to 30°C. (5) In step k-1), if PG 1 is a benzyloxycarbonyl group (Cbz), the reaction temperature is selected from 20°C to 70°C. (6) In step k-1), if PG 1 is a benzyloxycarbonyl group (Cbz), the reaction solvent is selected from methanol, ethanol, tetrahydrofuran, ethyl acetate, DMF, DMAc, NMP, or water, and the mass volume ratio (g / mL) of the compound of formula IV-1 or its salt to the selected reaction solvent is selected from 1:5 to 1:

10. (7) In step k-2), if E is a hydroxyl group, the reaction proceeds under neutral conditions under the action of the condensing agent. The condensing agent is selected from DMTMM or HBTU. The molar ratio of the compound of formula IV-2-2 or its salt to the condensing agent is selected from 1:1 to 1:1.

5. (8) In step k-2), if E is a hydroxyl group, the molar ratio of the compound of formula IV-2-1 or its salt to the compound of formula IV-2-2 or its salt is selected from 1:0.8 to 1:1.

2. (9) In step k-2), if E is a hydroxyl group, the reaction temperature is selected from -15 to 50°C. A feature that satisfies one or more of the following conditions: A method for preparing the compound of formula II or a salt thereof as described in claim 14.

16. The method for preparing the compound of formula IV-2 or its salt is as follows: The compound of formula IV-1-1 or its salt is subjected to acidic or basic conditions under the conditions of formula R ８ Method 1 includes step j) reacting with an OH compound or a salt thereof to obtain a compound of formula IV-1 or a salt thereof, 【Chemistry 25】 The following steps: Step j-1) involves reacting a compound of formula IV-1-2 or a salt thereof with formaldehyde in water under basic conditions to obtain a compound of formula IV-1-3 or a salt thereof. 【Chemistry 26】 The compound of formula IV-1-3 or its salt is subjected to acidic conditions, ８ Method 2 includes step j-2) reacting with an OH compound or a salt thereof to obtain a compound of formula IV-1 or a salt thereof, The present invention further includes a method for preparing a compound of formula IV-1 or a salt thereof, 【Chemistry 27】 In the formula, L ３－１ PG １ , R ８ The definition is as described in any one form of claim 12, A method for preparing the compound of formula II or a salt thereof as described in claim 12.

17. (1) In step j), the acid under the acidic conditions is a protonic acid or a non-protonic acid. (2) In step j), the base in the basic conditions is an organic base or an inorganic base, (3) In step j), the compound of formula IV-1-1 or a salt thereof and formula R ８ The molar ratio of the OH compound or its salt is selected from 1:1 to 1:

20. (4) In step j), the reaction solvent is selected from alcohol-based, ether-based, haloalkane-based, aromatic hydrocarbon-based, nitrile-based, amide-based, or sulfone-based solvents, and the mass volume ratio (g / mL) of the compound of formula IV-1-1 or its salt to the selected solvent is selected from 1:2 to 1:

10. (5) In step j), the reaction temperature is selected from 0 to 120°C. (6) In step j-1), the base in the basic conditions is selected from potassium carbonate, potassium bicarbonate, potassium phosphate, sodium carbonate, sodium bicarbonate, triethylamine, and diisopropylethylamine. (7) In step j-1), the molar ratio of the compound of formula IV-1-2 or its salt to the base under the basic conditions is selected from 1:0.05 to 1:

1. (8) In step j-1), the molar ratio of the compound of formula IV-1-2 or its salt to formaldehyde is selected from 1:0.5 to 1:2.

5. (9) In step j-1), the mass-volume ratio (g / mL) of the compound of formula IV-1-2 or its salt to water is selected from 1:3 to 1:

50. (10) In step j-1), the reaction temperature is selected from 0 to 80°C. (11) In step j-2), the acid under the acidic conditions is a protonic acid or a non-protonic acid. (12) In step j-2), the compound of formula IV-1-3 or a salt thereof and formula R ８ The molar ratio of the OH compound or its salt is selected from 1:1 to 1:

50. (13) In step j-2), the reaction solvent is selected from alcohol-based, ether-based, haloalkane-based, aromatic hydrocarbon-based, nitrile-based, amide-based, or sulfone-based solvents, and the mass volume ratio (g / mL) of the compound of formula IV-1-3 or its salt to the selected solvent is selected from 1:2 to 1:

10. (14) In step j-2), the reaction temperature is selected from 0 to 120°C. A feature that satisfies one or more of the following conditions: A method for preparing the compound of formula II or a salt thereof as described in claim 16.

18. (1) In step j), the acid under the acidic conditions is selected from hydrogen chloride, hydrobromic acid, sulfuric acid, trifluoroacetic acid, p-toluenesulfonic acid, pyridinium salt of p-toluenesulfonate, zinc acetate, aluminum trichloride (AlCl3), ferric chloride (FeCl3), boron trifluoride diethyl ether (BF3・Et2O), and ytterbium trifluoromethanesulfonate (Yb(OTf)3), and the molar ratio of the compound of formula IV-1-1 or its salt to the acid selected for reaction is selected from 1:0.01 to 1:0.

2. (2) In step j), the base in the basic conditions is selected from sodium hydroxide, potassium tert-butoxide, potassium carbonate, triethylamine (Et3N), N,N-diisopropylethylamine (DIPEA), and pyridine, and the molar ratio of the compound of formula IV-1-1 or its salt to the base selected for the reaction is selected from 1:0.9 to 1:

5. (3) In step j), the molar ratio of the compound of formula IV-1-1 or its salt to the compound of formula R 8 OH or its salt is selected from 1:2 to 1:

15. (4) In step j), the reaction solvent is selected from isopropanol, benzyl alcohol, tert-butanol, 2,2,2-trifluoroethanol, 2,2,3,3,3-pentafluoro-1-propanol, ethylene glycol diethyl ether, tetrahydrofuran, 1,4-dioxane, dichloromethane, 1,2-dichloroethane, toluene, acetonitrile, DMF, DMAc, NMP, or DMSO, and the mass-volume ratio (g / mL) of the compound of formula IV-1-1 or its salt to the selected solvent is selected from 1:2.5 to 1:

7. (5) In step j), the reaction temperature is selected from 10 to 50°C. (6) In step j-1), the base is potassium carbonate, (7) In step j-1), the molar ratio of the compound of formula IV-1-2 or its salt to the base is selected from 1:0.1 to 1:0.

5. (8) In step j-1), the molar ratio of the compound of formula IV-1-2 or its salt to formaldehyde is selected from 1:1 to 1:

2. (9) In step j-1), the mass-volume ratio (g / mL) of the compound of formula IV-1-2 or its salt to water is selected from 1:5 to 1:

20. (10) In step j-1), the reaction temperature is selected from 10 to 50°C. (11) In step j-2), the acid under the acidic conditions is selected from hydrogen chloride, hydrobromic acid, sulfuric acid, trifluoroacetic acid, p-toluenesulfonic acid, pyridinium salt of p-toluenesulfonic acid, zinc acetate, aluminum trichloride (AlCl3), ferric chloride (FeCl3), boron trifluoride diethyl ether (BF3·Et2O), and ytterbium trifluoromethanesulfonate (Yb(OTf)3), and the molar ratio of the compound of formula IV-1-3 or its salt to the acid selected for reaction is selected from 1:0.01 to 1:0.

2. (12) In step j-2), the molar ratio of the compound of formula IV-1-3 or its salt to the compound of formula R 8 OH or its salt is selected from 1:2 to 1:

30. (13) In step j-2), the reaction solvent is selected from isopropanol, benzyl alcohol, tert-butanol, 2,2,2-trifluoroethanol, 2,2,3,3,3-pentafluoro-1-propanol, ethylene glycol diethyl ether, tetrahydrofuran, 1,4-dioxane, dichloromethane, 1,2-dichloroethane, toluene, acetonitrile, DMF, DMAc, NMP, or DMSO, and the mass-volume ratio (g / mL) of the compound of formula IV-1-3 or its salt to the selected solvent is selected from 1:2.5 to 1:

7. (14) In step j-2), the reaction temperature is selected from 0 to 50°C. A feature that satisfies one or more of the following conditions: A method for preparing the compound of formula II or a salt thereof as described in claim 17.

19. The method for preparing the compound of formula II or its salt includes a method for preparing the compound of formula IIa or its salt, in which the compound of formula III or its salt is reacted with the compound of formula X-3a or its salt after azeotropic dehydration to obtain the compound of formula IIa or its salt. 【Chemistry 28】 A method for preparing the compound of formula II or a salt thereof according to claim 1, characterized in that

20. A method for preparing a compound of formula IIa or a salt thereof is: Step m-1) removes the protecting group Cbz from the compound of formula IV-2-A or a salt thereof under a metal reagent-hydrogen system to obtain the compound of formula X-3-1-A or a salt thereof, 【Chemistry 29】 A method for preparing a compound of formula X-3a or a salt thereof further includes step m-2) reacting a compound of formula X-3-1-A or a salt thereof with a compound of formula X-1-A under basic conditions to obtain a compound of formula X-3a or a salt thereof, 【Transformation 30】 A method for preparing a compound of formula II or a salt thereof according to claim 19, characterized in that

21. A method for preparing a compound of formula IIa or a salt thereof is: Step k-1) removes the protecting group Cbz from the compound of formula IV-1-A or a salt thereof under a metal reagent-hydrogen system to obtain the compound of formula IV-2-1-A or a salt thereof, 【Chemistry 31】 A method for preparing a compound of formula IV-2-A or a salt thereof further comprises step k-2), which involves reacting a compound of formula IV-2-1-A or a salt thereof with a compound of formula IV-2-2-B or a salt thereof under basic or neutral conditions under the action of a condensing agent and / or a racemization inhibitor to obtain a compound of formula IV-2-A or a salt thereof. 【Chemistry 32】 A method for preparing the compound of formula II or a salt thereof according to claim 20, characterized in that

22. A method for preparing a compound of formula IIa or a salt thereof is: Step j-1) involves reacting a compound of formula IV-1-A-2 or a salt thereof with formaldehyde in water under basic conditions to obtain a compound of formula IV-1-A-3 or a salt thereof, 【Transformation 33】 The compound of formula IV-1-A-3 or its salt is subjected to CF under acidic conditions. ３ CH ２ The method for preparing a compound of formula IV-1-A or a salt thereof further comprises step j-2) reacting with OH to obtain a compound of formula IV-1-A or a salt thereof, 【Transformation 34】 A method for preparing the compound of formula II or a salt thereof according to claim 21, characterized in that

23. A method for preparing a compound of formula X-3 or a salt thereof, Protecting group PG on amino group from compound of formula IV-2 or its salt ２ Step m-1) removes the compound of formula X-3-1 or a salt thereof, 【Chemistry 35】 The process includes step m-2) obtaining a compound of formula X-3 or a salt thereof by a condensation reaction between a compound of formula X-3-1 or a salt thereof and a compound of formula X-1, 【Transformation 36】 During the ceremony, E is selected from a hydroxyl group, halogen, or activated hydroxyl group. PG ２ It is selected from amino protecting groups, Lg is MeSO₂-, L1 is, 【Chemistry 37】 Selected from, the 1st place is linked to Lg, the 2nd place is linked to L2, L2 is 【Transformation 38】 Selected from, the 1st place is connected to L1, the 2nd place is connected to L3, n4 is selected from any integer between 0 and 10. Y is selected from -CH2- and -OCH2CH2-. Z is selected from CR m R n, NR m, R m and R n are each independently selected from H, deuterium, C1-4 alkyl groups, C2-4 alkenyl groups, C2-4 alkynyl groups, C3-6 cycloalkyl groups, and 3-6 membered heterocyclic groups. Alternatively, R m and R n, together with the carbon atoms linked to them, form a 3-6 membered carbon ring or a 3-6 membered heterocycle. L 3 is Val-Ala, AA 1 -Val-Ala, Val-AA 1 -Gly, Ala-AA 1 -Gly, Gly-AA 1 -Gly, Val-AA 1 -Ala, Val-AA 1 -Val, Ala-AA 1 -Ala, Ala-AA 1 -Val, Gly-AA 1 -Ala, Gly-AA 1 -Val, Ala-Ala-Ala, Ala-Ala-Asn, Gly-Gly-Phe-Gly, and Gly-Gly-Val-Ala, The structure of the amino acid residue shown in AA1 is shown as follows: 【Chemistry 39】 During the ceremony, Ra and Rb are each independently of H and 【Chemistry 40】 Selected from, and Ra a and R b are not H at the same time, Alternatively, Ra and Rb, together with the carbon atoms linked to them, form a 4- to 10-membered heterocycle, and the 4- to 10-membered heterocycle is optionally substituted with one or more R0s. r is 0, and r1 is 4. R m1 and R n1 are each independently selected from H, C1-6 alkyl groups, and C3-6 cycloalkyl groups. Alternatively, R m1 and R n1, together with the nitrogen atom linked to them, form a 4- to 10-membered heterocycle, and the 4- to 10-membered heterocycle is optionally substituted with one or more R 0' atoms. R0 and R0' are each independently selected from C1-6 alkyl groups, C3-6 cycloalkyl groups, -NR m2 R n2, and optionally substituted 4-10 membered heterocyclic groups with C1-6 alkyl groups. R m2 and R n2 are each independently selected from H and C1-6 alkyl groups. R8 is selected from hydrogen, C1-30 alkyl groups, C3-7 cycloalkyl groups, 3-20 membered heterocyclic groups, C1-6 alkyl groups-C3-6 cycloalkyl groups, C1-6 alkyl groups-4-6 membered heterocyclic groups, C1-6 alkyl groups-C5-10 heteroaryl groups, and C1-6 alkyl groups-C6-10 aryl groups, and the alkyl groups, cycloalkyl groups, heterocyclic groups, and aryl groups are optionally substituted with one or more Rx. R x is selected from hydrogen, deuterium, fluorine, chlorine, bromine, methyl group, methoxy group, amino group, dimethylamino group, nitro group, cyano group, and azide group. Characterized by, A method for preparing the compound of formula X-3 or a salt thereof.

24. A method for preparing a compound of formula IV-2 or a salt thereof, wherein R ８ If it is not H, Protecting group PG on amino group from compound of formula IV-1 or its salt １ Step k-1) removes the compound of formula IV-2-1 or a salt thereof, 【Chemistry 41】 The process includes step k-2), which involves a condensation reaction between a compound of formula IV-2-1 or a salt thereof and a compound of formula IV-2-2 or a salt thereof to obtain a compound of formula IV-2 or a salt thereof. 【Chemistry 42】 In the formula, P.G. ２ -L ３ That is, PG ２ -L ３－２ -L ３－１ And, During the ceremony, L3-1 is selected from amino acid residues, and the amino acid residues are 【Chemistry 43】 Selected from, the 1st place team is linked to PG 1 or H, the 2nd place team is linked to NH, PG 1 is selected from amino protecting groups, L3-2 is selected from Val, Val-AA1, Ala-AA1, Gly-AA1, Ala-Ala, AA1-Val, Gly-Gly-Val and Gly-Gly-Phe. L 3 is Val-Ala, AA 1 -Val-Ala, Val-AA 1 -Gly, Ala-AA 1 -Gly, Gly-AA 1 -Gly, Val-AA 1 -Ala, Val-AA 1 -Val, Ala-AA 1 -Ala, Ala-AA 1 -Val, Gly-AA 1 -Ala, Gly-AA 1 -Val, Ala-Ala-Ala, Ala-Ala-Asn, Gly-Gly-Phe-Gly, and Gly-Gly-Val-Ala, The structure of the amino acid residue shown in AA1 is shown as follows: 【Chemistry 44】 During the ceremony, Ra and Rb are each independently of H and 【Chemistry 45】 Selected from, and Ra a and R b are not H at the same time, Alternatively, Ra and Rb, together with the carbon atoms linked to them, form a 4- to 10-membered heterocycle, and the 4- to 10-membered heterocycle is optionally substituted with one or more R0s. r is 0, and r1 is 4. R m1 and R n1 are each independently selected from H, C1-6 alkyl groups, and C3-6 cycloalkyl groups. Alternatively, R m1 and R n1, together with the nitrogen atom linked to them, form a 4- to 10-membered heterocycle, and the 4- to 10-membered heterocycle is optionally substituted with one or more R 0' atoms. R0 and R0' are each independently selected from C1-6 alkyl groups, C3-6 cycloalkyl groups, -NR m2 R n2, and optionally substituted 4-10 membered heterocyclic groups with C1-6 alkyl groups. R m2 and R n2 are each independently selected from H and C1-6 alkyl groups. R8 is selected from hydrogen, C1-30 alkyl groups, C3-7 cycloalkyl groups, 3-20 membered heterocyclic groups, C1-6 alkyl groups-C3-6 cycloalkyl groups, C1-6 alkyl groups-4-6 membered heterocyclic groups, C1-6 alkyl groups-C5-10 heteroaryl groups, and C1-6 alkyl groups-C6-10 aryl groups, and the alkyl groups, cycloalkyl groups, heterocyclic groups, and aryl groups are optionally substituted with one or more Rx. Rx is selected from hydrogen, deuterium, fluorine, chlorine, bromine, methyl group, methoxy group, amino group, dimethylamino group, nitro group, cyano group, and azide group. E is selected from a hydroxyl group, halogen, or activated hydroxyl group. PG2 is selected from amino protecting groups. Characterized by, A method for preparing a compound of formula IV-2 or a salt thereof.

25. A method for preparing a compound of formula IV-1 or a salt thereof, The compound of formula IV-1-1 or its salt is subjected to acidic or basic conditions under the conditions of formula R ８ Method 1 includes step j) reacting with an OH compound or a salt thereof to obtain a compound of formula IV-1 or a salt thereof, 【Chemistry 46】 The following steps: Step j-1) involves reacting a compound of formula IV-1-2 or a salt thereof with formaldehyde in water under basic conditions to obtain a compound of formula IV-1-3 or a salt thereof. 【Chemistry 47】 The compound of formula IV-1-3 or its salt is subjected to acidic conditions, ８ Method 2 includes step j-2) reacting with an OH compound or a salt thereof to obtain a compound of formula IV-1 or a salt thereof, 【Chemistry 48】 During the ceremony, L3-1 is selected from amino acid residues, and the amino acid residues are 【Chemistry 49】 Selected from, the 1st place team is linked to PG 1, the 2nd place team is linked to NH, PG 1 is selected from amino protecting groups, R8 is selected from hydrogen, C1-30 alkyl groups, C3-7 cycloalkyl groups, 3-20 membered heterocyclic groups, C1-6 alkyl groups-C3-6 cycloalkyl groups, C1-6 alkyl groups-4-6 membered heterocyclic groups, C1-6 alkyl groups-C5-10 heteroaryl groups, and C1-6 alkyl groups-C6-10 aryl groups, and the alkyl groups, cycloalkyl groups, heterocyclic groups, and aryl groups are optionally substituted with one or more Rx. R x is selected from hydrogen, deuterium, fluorine, chlorine, bromine, methyl group, methoxy group, amino group, dimethylamino group, nitro group, cyano group, and azide group. Characterized by, A method for preparing a compound of formula IV-1 or a salt thereof.

26. A compound of formula IV-1 or a salt thereof, a compound of formula IV-2-1 or a salt thereof, a compound of formula IV-2 or a salt thereof, a compound of formula X-3-1 or a salt thereof, a compound of formula X-3 or a salt thereof, [Transformation 50] Lg is MeSO₂-, L1 is, 【Chemistry 51】 Selected from, the 1st place is linked to Lg, the 2nd place is linked to L2, L2 is 【Chemistry 52】 Selected from, the 1st place is connected to L1, the 2nd place is connected to L3, n4 is selected from any integer between 0 and 10. Y is selected from -CH2- and -OCH2CH2-. Z is selected from CR m R n, NR m, R m and R n are each independently selected from H, deuterium, C1-4 alkyl groups, C2-4 alkenyl groups, C2-4 alkynyl groups, C3-6 cycloalkyl groups, and 3-6 membered heterocyclic groups. Alternatively, R m and R n, together with the carbon atoms linked to them, form a 3-6 membered carbon ring or a 3-6 membered heterocycle. L 3 is Val-Ala, AA 1 -Val-Ala, Val-AA 1 -Gly, Ala-AA 1 -Gly, Gly-AA 1 -Gly, Val-AA 1 -Ala, Val-AA 1 -Val, Ala-AA 1 -Ala, Ala-AA 1 -Val, Gly-AA 1 -Ala, Gly-AA 1 -Val, Ala-Ala-Ala, Ala-Ala-Asn, Gly-Gly-Phe-Gly, and Gly-Gly-Val-Ala, The structure of the amino acid residue shown in AA1 is shown as follows: 【Chemistry 53】 During the ceremony, Ra and Rb are each independently of H and 【Chemistry 54】 Selected from, and Ra a and R b are not H at the same time, Alternatively, Ra and Rb, together with the carbon atoms linked to them, form a 4- to 10-membered heterocycle, and the 4- to 10-membered heterocycle is optionally substituted with one or more R0s. r is 0, and r1 is 4. R m1 and R n1 are each independently selected from H, C1-6 alkyl groups, and C3-6 cycloalkyl groups. Alternatively, R m1 and R n1, together with the nitrogen atom linked to them, form a 4- to 10-membered heterocycle, and the 4- to 10-membered heterocycle is optionally substituted with one or more R 0' atoms. R0 and R0' are each independently selected from C1-6 alkyl groups, C3-6 cycloalkyl groups, -NR m2 R n2, and optionally substituted 4-10 membered heterocyclic groups with C1-6 alkyl groups. R m2 and R n2 are each independently selected from H and C1-6 alkyl groups. R8 is selected from hydrogen, C1-30 alkyl groups, C3-7 cycloalkyl groups, 3-20 membered heterocyclic groups, C1-6 alkyl groups-C3-6 cycloalkyl groups, C1-6 alkyl groups-4-6 membered heterocyclic groups, C1-6 alkyl groups-C5-10 heteroaryl groups, and C1-6 alkyl groups-C6-10 aryl groups, and the alkyl groups, cycloalkyl groups, heterocyclic groups, and aryl groups are optionally substituted with one or more Rx. Rx is selected from hydrogen, deuterium, fluorine, chlorine, bromine, methyl group, methoxy group, amino group, dimethylamino group, nitro group, cyano group, and azide group. PG2 is selected from amino protecting groups, L3-1 is selected from amino acid residues, and the amino acid residues are 【Transformation 55】 Selected from, the 1st place team is linked to PG 1 or H, the 2nd place team is linked to NH, PG 1 is selected from amino protecting groups, The compound of formula IV-1 is not selected from the following structures. 【Transformation 56】

27. ​​The compound of formula IV-1 or a salt thereof has the following structure: 【Chemistry 57】 Selected from, The compound of formula IV-2-1 or its salt has the following structure: 【Transformation 58】 Selected from, The compound of formula IV-2 or its salt has the following structure: 【Chemistry 59】 Selected from, The compound of formula X-3-1 or its salt has the following structure: 【Transformation 60】 Selected from, The compound of formula X-3 or its salt has the following structure: 【Chemistry 61】 【Transformation 62】 A compound or salt thereof of formula IV-1, a compound or salt thereof of formula IV-2-1, a compound or salt thereof of formula IV-2, a compound or salt thereof of formula X-3-1, or a compound or salt thereof of formula X-3, selected from the above, according to claim 26.

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