阅读说明：本技术 在主链和侧链具有单分散聚乙二醇的异双官能性化合物 (Heterobifunctional compounds having monodisperse polyethylene glycol in main and side chains ) 是由 义村耕平 粒崎拓真 羽村美华 松野佑纪 于 2019-03-11 设计创作，主要内容包括：一种如式(1)所示的异双官能性单分散聚乙二醇：<Image he="153" wi="700" file="DDA0002675609890000011.GIF" imgContent="drawing" imgFormat="GIF" orientation="portrait" inline="no"></Image>X<Sup>1</Sup>和Y<Sup>1</Sup>各自为包含能够在与生物功能分子中存在的官能团的反应中形成共价键的官能团的原子团,原子团X<Sup>1</Sup>包含的官能团与原子团Y<Sup>1</Sup>包含的官能团互不相同；R<Sup>1</Sup>是具有1至7个碳原子的烃基或氢原子；n是3至72的整数；l是2至72的整数；A<Sup>1</Sup>表示-L<Sup>1</Sup>-(CH<Sub>2</Sub>)<Sub>m1</Sub>-或-L<Sup>1</Sup>-(CH<Sub>2</Sub>)<Sub>m1</Sub>-L<Sup>2</Sup>-(CH<Sub>2</Sub>)<Sub>m2</Sub>-,L<Sup>1</Sup>表示特定的键或单键,L<Sup>2</Sup>表示特定的键,并且m1和m2各自独立地表示1至5的整数；B<Sup>1</Sup>表示-L<Sup>3</Sup>-(CH<Sub>2</Sub>)<Sub>m3</Sub>-、-L<Sup>3</Sup>-(CH<Sub>2</Sub>)<Sub>m3</Sub>-L<Sup>4</Sup>-(CH<Sub>2</Sub>)<Sub>m4</Sub>-或单键,L<Sup>3</Sup>表示酰胺键或单键,L<Sup>4</Sup>表示特定的键,并且m3和m4各自独立地表示1至5的整数；并且C<Sup>1</Sup>表示-L<Sup>5</Sup>-(CH<Sub>2</Sub>)<Sub>m5</Sub>-、-O-CH<Sub>2</Sub>-或单键,L<Sup>5</Sup>表示特定的键或单键,并且m5表示1至5的整数。(A hetero-bifunctional monodisperse polyethylene glycol of formula (1): X 1 and Y 1 Each being a radical comprising a functional group capable of forming a covalent bond in reaction with a functional group present in a biofunctional molecule, radical X 1 Containing functional groups and radicals Y 1 The functional groups contained are different from each other; r 1 Is a hydrocarbon group having 1 to 7 carbon atoms or a hydrogen atom; n is an integer from 3 to 72; l is an integer from 2 to 72; a. the 1 Is represented by-L 1 ‑(CH 2 ) m1 -or-L 1 ‑(CH 2 ) m1 ‑L 2 ‑(CH 2 ) m2 ‑，L 1 Represents a specific bond or single bond, L 2 Represents a specific bond, and m1 and m2 each independently represent an integer of 1 to 5; b is 1 Is represented by-L 3 ‑(CH 2 ) m3 ‑、‑L 3 ‑(CH 2 ) m3 ‑L 4 ‑(CH 2 ) m4 -or a single bond, L 3 Represents an amide bond or a single bond, L 4 Represents a specific bond, and m3 and m4 each independently represent an integer of 1 to 5; and C 1 Is represented by-L 5 ‑(CH 2 ) m5 ‑、‑O‑CH 2 -or a single bond, L 5 Represents a specific bond or single bond, and m5 represents an integer of 1 to 5.)

1. A hetero-bifunctional monodisperse polyethylene glycol of formula (1):

wherein, in the formula (1),

X¹and Y¹Each being a radical comprising at least one functional group capable of forming a covalent bond in reaction with a functional group present in a biofunctional molecule, the radical X¹Containing functional groups and radicals Y¹The functional groups contained are different from each other;

R¹is a hydrocarbon group having 1 to 7 carbon atoms or a hydrogen atom;

n is an integer from 3 to 72;

l is an integer from 2 to 72;

A¹is represented by-L¹-(CH₂)_m1-or-L¹-(CH₂)_m1-L²-(CH₂)_m2-，L¹Represents an ether bond, an amide bond, a urethane bond, a secondary amino group or a single bond, L²Represents an amide bond or a urethane bond, and m1 and m2 each independently represent an integer of 1 to 5;

B¹is represented by-L³-(CH₂)_m3-、-L³-(CH₂)_m3-L⁴-(CH₂)_m4-or a single bond, L³Represents an amide bond or a single bond, L⁴Represents an ether bond, an amide bond or a urethane bond, and m3 and m4 each independently represent an integer of 1 to 5; and is

C¹Is represented by-L⁵-(CH₂)_m5-、-O-CH₂-or a single bond, L⁵Represents an amide bond, a urethane bond, a secondary amino group or a single bond, and m5 represents an integer of 1 to 5.

2. According to claim1, wherein, in the formula (1), A is¹represents-NHC (O) - (CH)₂)_m1-or-NHC (O) - (CH)₂)_m1-L²-(CH₂)_m2-，B¹Is represented by- (CH)₂)_m3-or- (CH)₂)_m3-L⁴-(CH₂)_m4-, and C¹Is represented by-L⁵-(CH₂)_m5-、-O-CH₂-or a single bond.

3. The hetero-bifunctional monodisperse polyethylene glycol of claim 1, wherein in formula (1), A is¹represents-CH₂-or-CH₂-L²-(CH₂)_m2-，B¹represents-CH₂-or-CH₂-L⁴-(CH₂)_m4-, and C¹Is represented by-L⁵-(CH₂)_m5-、-O-CH₂-or a single bond.

4. The hetero-bifunctional monodisperse polyethylene glycol of claim 1, wherein in formula (1), A is¹represents-O- (CH)₂)_m1-or-O- (CH)₂)_m1-L²-(CH₂)_m2-，B¹represents-CH₂-or-CH₂-L⁴-(CH₂)_m4-, and C¹Is represented by-L⁵-(CH₂)_m5-、-O-CH₂-or a single bond.

5. The hetero-bifunctional monodisperse polyethylene glycol of claim 1, wherein in formula (1), A is¹represents-C (O) NH- (CH)₂)_m1-or-C (O) NH- (CH)₂)_m1-L²-(CH₂)_m2-，B¹represents-CH₂-or-CH₂-L⁴-(CH₂)_m4-, and C¹Is represented by-L⁵-(CH₂)_m5-、-O-CH₂-or a single bond.

6. The hetero-bifunctional monodisperse polyethylene glycol of claim 1, wherein in formula (1), A is¹represents-C (O) NH- (CH)₂)_m1-or-C (O) NH- (CH)₂)_m1-L²-(CH₂)_m2-，B¹represents-C (O) NH- (CH)₂)_m3-or-C (O) NH- (CH)₂)_m3-L⁴-(CH₂)_m4-, and C¹Is represented by-L⁵-(CH₂)_m5-、-O-CH₂-or a single bond.

7. The hetero-bifunctional monodisperse polyethylene glycol of any one of claims 1-6, wherein in formula (1), X is¹And Y¹Each independently selected from the group consisting of formula (a), formula (b1), formula (b2), formula (c), formula (d), formula (e), formula (f), formula (g), formula (h), formula (i), formula (j), formula (k), formula (l), formula (m), formula (n), and formula (o):

wherein, in the formula (d), R²Is a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms; in the formula (e), R³Is a halogen atom selected from a chlorine atom, a bromine atom and an iodine atom; and in said formula (l), R⁴Is a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms.

8. An antibody-drug conjugate comprising a heterobifunctional monodisperse polyethylene glycol represented by formula (2):

wherein, in the formula (2),

X²and Y²One is an antibody and the other is a drug;

R¹is a hydrocarbon group having 1 to 7 carbon atoms or a hydrogen atom;

n is an integer from 3 to 72;

l is an integer from 2 to 72;

A¹is represented by-L¹-(CH₂)_m1-or-L¹-(CH₂)_m1-L²-(CH₂)_m2-，L¹Represents an ether bond, an amide bond, a urethane bond, a secondary amino group or a single bond, L²Represents an amide bond or a urethane bond, and m1 and m2 each independently represent an integer of 1 to 5;

B²is represented by-L³-(CH₂)_m3-L⁶、-L³-(CH₂)_m3-L⁴-(CH₂)_m4-L⁶or-L⁶-，L³Represents an amide bond or a single bond, L⁴Represents an ether bond, an amide bond or a urethane bond, m3 and m4 each independently represent an integer of 1 to 5, and L⁶Is an amide bond, a carbamate bond, a thioether bond, a disulfide bond, a carbonate bond, an ester bond, an ether bond, a 1H-1,2, 3-triazole-1, 4-diyl structure, a secondary amino group, a hydrazide group, an oxoamide group, or a hydrocarbon group containing any of the above; and is

C²Is represented by-L⁵-(CH₂)_m5-L⁷-、-O-CH₂-L⁷-or-L⁷-，L⁵Represents an amide bond, a urethane bond, a secondary amino group or a single bond, m5 represents an integer of 1 to 5, and L⁷An amide bond, a carbamate bond, a thioether bond, a disulfide bond, a carbonate bond, an ester bond, an ether bond, a 1H-1,2, 3-triazole-1, 4-diyl structure, a secondary amino group, a hydrazide group, an oxoamide group, or a hydrocarbon group containing any of the above.

Technical Field

The invention relates to heterobifunctional compounds having monodisperse polyethylene glycols in the main chain and side chains and having two different chemically reactive functional groups. More particularly, the present invention relates to hetero-bifunctional compounds having monodisperse polyethylene glycol in the main chain and side chains and having two different chemically reactive functional groups, which are used for modifying biofunctional molecules such as physiologically active proteins, peptides, antibodies, nucleic acids or low molecular weight drugs, drug carriers in drug delivery systems, diagnostic materials or medical devices, etc., and which are particularly useful for modifying antibody drugs.

Background

An Antibody-Drug Conjugate (ADC) is an Antibody Drug in which the Drug binds to the Antibody and is targeted to actively transport the Drug to the site of disease through the antigen specificity of the Antibody. In recent years, it is one of the fastest growing technologies in the field of cancer treatment. ADCs are made up of various portions of an antibody, a drug, and a linker for linking the antibody and the drug.

Many of the drugs used for ADCs are hydrophobic, and when a plurality of such hydrophobic drugs are bound to antibodies to prepare ADCs, there are problems in that aggregation occurs due to the hydrophobicity of the drugs or the stability of the antibodies in blood is decreased. Therefore, the number of drugs that can be carried per antibody is limited, and as a result, the pharmaceutical effect of ADC cannot be sufficiently obtained in some cases.

One of the solutions studied for this problem is the use of hydrophilic linkers. As the hydrophilic linker, polyethylene glycol, a hydrophilic peptide, a sugar chain, and the like are used. In particular, polyethylene glycol is used in a plurality of ADCs in clinical trials and pre-clinical trial stages because of its low antigenicity and high biocompatibility.

In the field of ADCs, compounds containing more than 90% of components with specific ethylene glycol chain lengths are used for the purpose of ensuring the homogeneity of the ADC and simplifying its purification, analysis and pharmaceutical approval processes. Such compounds are known as monodisperse polyethylene glycols.

In the case of using monodisperse polyethylene glycol as a linker of ADC, since it is necessary to separately bind an antibody and a drug, a heterobifunctional monodisperse polyethylene glycol having two different chemically reactive functional groups is used. In general, ADCs are prepared using compounds having chemically reactive functional groups different from each other at both ends of a monodisperse polyethylene glycol chain.

However, in recent years, an ADC has been reported which does not use monodisperse polyethylene glycol as a linker backbone for linking an antibody and a drug, and introduces monodisperse polyethylene glycol as a side chain of a branched linker for linking the antibody and the drug.

In non-patent document 1, the pharmacokinetics and therapeutic effects of ADCs using monodisperse polyethylene glycol as a linker backbone linking an antibody and a drug and ADCs using monodisperse polyethylene glycol as a side chain linking a branched linker of an antibody and a drug are compared, and it is reported that the latter ADCs have a high masking effect on the hydrophobicity of a drug and exhibit excellent pharmacokinetics and therapeutic effects.

In addition, patent document 2 and patent document 3 disclose various types of ADCs having monodisperse polyethylene glycol as a side chain of a branched linker, and intermediates for producing these ADCs.

Incidentally, patent document 1 discloses a polyethylene glycol derivative having a pentaerythritol skeleton and having four polyethylene glycol chains and two types of functional groups at the ends of the polyethylene glycol chains.

Disclosure of Invention

Problems to be solved by the invention

Patent document 1 discloses only a compound having four polyethylene glycol chains on a pentaerythritol skeleton and two types of functional groups at the ends of the polyethylene glycol chains. This is because in the functionalization reaction, the terminal hydroxyl group of the four-chain polyethylene glycol derivative having pentaerythritol as a backbone is derivatized to other functional groups, and then a mono-or di-derivatized product is obtained by column purification.

In the case of preparing an ADC using a polyethylene glycol derivative disclosed in patent document 1, the ADC to be prepared is an ADC in which an antibody and a drug are bound to the terminal of the polyethylene glycol derivative, that is, an ADC in which polyethylene glycol is used as a linker backbone for linking the antibody and the drug.

In ADCs having monodisperse polyethylene glycol as a side chain of a branched linker described in non-patent document 1, patent document 2, or patent document 3, an amino acid having an asymmetric carbon is used in a branched portion of a linker to which monodisperse polyethylene glycol is bound.

In the case where a linker having a desired chemical structure is constructed through various chemical conversion processes using a compound having such a chiral center, partial stereoreversal or racemization of the undesired chiral center occurs in, for example, acidic or basic reaction conditions, a reaction in the presence of an organic or inorganic catalyst, or a reaction in the presence of a condensing agent, which are involved in the chemical conversion processes, and thus there is a possibility that a mixture of stereoisomers is formed. It is very difficult to separate a compound having a desired three-dimensional structure from a mixture of stereoisomers. The use of such a mixture of stereoisomers as a linker to link the antibody and drug is not preferred due to the formation of heterogeneous ADCs.

Patent document 2 or patent document 3 also discloses ADCs having two or more monodisperse polyethylene glycols in the side chain of the branched linker. However, the binding sites of the respective monodisperse polyethylene glycol side chains are separated, and since the "umbrella-like structure" (Biomaterials 2001,22(5), 405-.

The object of the present invention is to provide: a heterobifunctional monodisperse polyethylene glycol having monodisperse polyethylene glycol in the main chain, having two adjacent monodisperse polyethylene glycol side chains and having no chiral center in the molecular structure; and an antibody-drug conjugate in which an antibody and a drug are linked using the heterobifunctional monodisperse polyethylene glycol.

Means for solving the problems

As a result of extensive research to solve the above problems, the inventors developed: a hetero-bifunctional monodisperse polyethylene glycol as a hetero-bifunctional compound, wherein a monodisperse polyethylene glycol is present in a main chain and two adjacent monodisperse polyethylene glycol side chains are adjacently bonded to each other and do not have a chiral center in a molecular structure; and an antibody-drug conjugate in which the antibody and the drug are linked using the heterobifunctional monodisperse polyethylene glycol.

In addition, in the hetero bifunctional monodisperse polyethylene glycol of the present invention, since two monodisperse polyethylene glycol side chains are bonded to the quaternary carbon atom of the branched moiety through a stable ether bond, it has a characteristic that it is difficult to decompose into single chain monodisperse polyethylene glycol during the chemical conversion of the structure of the hetero bifunctional monodisperse polyethylene glycol.

In addition, since the hetero-bifunctional monodisperse polyethylene glycol of the present invention has a monodisperse polyethylene glycol backbone capable of adjusting chain length, it has a feature that it is possible to avoid a decrease in reactivity due to steric hindrance between an antibody and a drug and not to impair hydrophilicity of ADC by increasing the chain length of the monodisperse polyethylene glycol in the binding of an antibody-linker compound and a drug or the binding of a drug-linker compound and an antibody.

Namely, the present invention is as follows:

[1] a hetero-bifunctional monodisperse polyethylene glycol represented by the formula (1):

(in the formula (1), X¹And Y¹Each being a radical comprising at least one functional group capable of forming a covalent bond in reaction with a functional group present in a biofunctional molecule, the radical X¹Containing functional groups and radicals Y¹The functional groups contained are different from each other; r¹Is a hydrocarbon group having 1 to 7 carbon atoms or a hydrogen atom; n is an integer from 3 to 72; l is an integer from 2 to 72; a. the¹Is represented by-L¹-(CH₂)_m1-or-L¹-(CH₂)_m1-L²-(CH₂)_m2-，L¹Represents an ether bond, an amide bond, a urethane bond, a secondary amino group or a single bond, L²Represents an amide bond or a urethane bond, and m1 and m2 each independently represent an integer of 1 to 5; b is¹Is represented by-L³-(CH₂)_m3-、-L³-(CH₂)_m3-L⁴-(CH₂)_m4-or a single bond, L³Represents an amide bond or a single bond, L⁴Represents an ether bond, an amide bond or a urethane bond, and m3 and m4 each independently represent an integer of 1 to 5; and C¹Is represented by-L⁵-(CH₂)_m5-、-O-CH₂-or a single bond, L⁵Represents an amide bond, a urethane bond, a secondary amino group or a single bond, and m5 represents an integer of 1 to 5. )

[2]According to [1]The hetero-bifunctional monodisperse polyethylene glycol wherein, in the formula (1), A is¹represents-NHC (O) - (CH)₂)_m1-or-NHC (O) - (CH)₂)_m1-L²-(CH₂)_m2-，B¹Is represented by- (CH)₂)_m3-or- (CH)₂)_m3-L⁴-(CH₂)_m4-, and C¹Is represented by-L⁵-(CH₂)_m5-、-O-CH₂-or a single bond.

[3]According to [1]The hetero-bifunctional monodisperse polyethylene glycol wherein, in the formula (1), A is¹represents-CH₂-or-CH₂-L²-(CH₂)_m2-，B¹represents-CH₂-or-CH₂-L⁴-(CH₂)_m4-, and C¹Is represented by-L⁵-(CH₂)_m5-、-O-CH₂-or a single bond.

[4]According to [1]The hetero-bifunctional monodisperse polyethylene glycol wherein, in the formula (1), A is¹represents-O- (CH)₂)_m1-or-O- (CH)₂)_m1-L²-(CH₂)_m2-，B¹represents-CH₂-or-CH₂-L⁴-(CH₂)_m4-, and C¹To represent-L⁵-(CH₂)_m5-、-O-CH₂-or a single bond.

[5]According to [1]The hetero-bifunctional monodisperse polyethylene glycol wherein, in the formula (1), A is¹represents-C (O) NH- (CH)₂)_m1-or-C (O) NH- (CH)₂)_m1-L²-(CH₂)_m2-，B¹represents-CH₂-or-CH₂-L⁴-(CH₂)_m4-, and C¹Is represented by-L⁵-(CH₂)_m5-、-O-CH₂-or a single bond.

[6]According to [1]The hetero-bifunctional monodisperse polyethylene glycol wherein, in the formula (1), A is¹represents-C (O) NH- (CH)₂)_m1-or-C (O) NH- (CH)₂)_m1-L²-(CH₂)_m2-，B¹represents-C (O) NH- (CH)₂)_m3-or-C (O) NH- (CH)₂)_m3-L⁴-(CH₂)_m4-, and C¹Is represented by-L⁵-(CH₂)_m5-、-O-CH₂-or a single bond.

[7]According to [1]To [6 ]]The hetero-bifunctional monodisperse polyethylene glycol of any one of above, wherein, in the formula (1), X is¹And Y¹Each independently selected from the group consisting of formula (a), formula (b1), formula (b2), formula (c), formula (d), formula (e), formula (f), formula (g), formula (h), formula (i), formula (j), formula (k), formula (l), formula (m), formula (n), and formula (o):

(in the formula (d), R²Is a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms; in the formula (e), R³Is a halogen atom selected from a chlorine atom, a bromine atom and an iodine atom; and in said formula (l), R⁴Is a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms. )

[8] An antibody-drug conjugate comprising a heterobifunctional monodisperse polyethylene glycol represented by formula (2):

(in the formula (2), X²And Y²One is an antibody and the other is a drug; r¹Is a hydrocarbon group having 1 to 7 carbon atoms or a hydrogen atom; n is an integer from 3 to 72; l is an integer from 2 to 72; a. the¹Is represented by-L¹-(CH₂)_m1-or-L¹-(CH₂)_m1-L²-(CH₂)_m2-，L¹Represents an ether bond, an amide bond, a urethane bond, a secondary amino group or a single bond, L²Represents an amide bond or a urethane bond, and m1 and m2 each independently represent an integer of 1 to 5; b is²Is represented by-L³-(CH₂)_m3-L⁶、-L³-(CH₂)_m3-L⁴-(CH₂)_m4-L⁶or-L⁶-，L³Represents an amide bond or a single bond, L⁴Represents an ether bond, an amide bond or a urethane bond, m3 and m4 each independently represent an integer of 1 to 5, and L⁶Is an amide bond, a carbamate bond, a thioether bond, a disulfide bond, a carbonate bond, an ester bond, an ether bond, a 1H-1,2, 3-triazole-1, 4-diyl structure, a secondary amino group, a hydrazide group, an oxoamide group, or a hydrocarbon group containing any of the above; and C²Is represented by-L⁵-(CH₂)_m5-L⁷-、-O-CH₂-L⁷-or-L⁷-，L⁵Represents an amide bond, a urethane bond, a secondary amino group or a single bond, m5 represents an integer of 1 to 5, and L⁷An amide bond, a carbamate bond, a thioether bond, a disulfide bond, a carbonate bond, an ester bond, an ether bond, a 1H-1,2, 3-triazole-1, 4-diyl structure, a secondary amino group, a hydrazide group, an oxoamide group, or a hydrocarbon group containing any of the above. )

ADVANTAGEOUS EFFECTS OF INVENTION

Since the hetero-bifunctional monodisperse polyethylene glycol according to the present invention does not have a chiral center, problems of partial stereoreversal or racemization of the undesired chiral center during chemical conversion do not fundamentally occur. In addition, since two monodisperse polyethylene glycol side chains are bonded to the quaternary carbon atom of the branched moiety through a stable ether bond, it is difficult to decompose into single chain monodisperse polyethylene glycol during chemical conversion. Therefore, by binding the antibody and the drug using the heterobifunctional monodisperse polyethylene glycol, an antibody-drug conjugate having high homogeneity can be obtained.

In addition, in the hetero-bifunctional monodisperse polyethylene glycol, since two monodisperse polyethylene glycol side chains are adjacently bonded to each other, when an antibody-drug conjugate is prepared, a masking effect on a hydrophobic drug is large, and thus aggregation occurrence due to hydrophobicity of the drug or a decrease in stability of the antibody in blood can be suppressed.

Drawings

FIG. 1 is a graph of HPLC measurements using a Hydrophobic Interaction Chromatography (HIC) column in example 8.

Fig. 2 is a graph of HPLC measurement using a Hydrophobic Interaction Chromatography (HIC) column in comparative example 7.

Fig. 3 is a graph of HPLC measurement using a Hydrophobic Interaction Chromatography (HIC) column in comparative example 14.

Detailed Description

Hereinafter, the present invention will be described in detail.

In this specification, "heterobifunctional" means having two different chemically reactive functional groups, and "monodisperse polyethylene glycol" means a compound comprising more than 90% of components having a specific ethylene glycol chain length.

The heterobifunctional monodisperse polyethylene glycol is shown as a formula (1).

R in the formula (1) of the present invention¹Is a hydrocarbon group or a hydrogen atom. The number of carbon atoms of the hydrocarbon group is preferably 7 or less. Examples of the hydrocarbon group include alkyl groups, aryl groups and aralkyl groups, and the hydrocarbon group specifically includes methyl groups, ethyl groups, propyl groups, isopropyl groups, tert-butyl groups, phenyl groups and benzyl groups. R¹Is a methyl group or a hydrogen atom, more preferably a methyl group.

N in formula (1) of the present invention represents the number of repeating units of monodisperse polyethylene glycol, and is an integer of 3 to 72, preferably an integer of 4 to 48, more preferably an integer of 6 to 36, and particularly preferably an integer of 8 to 24.

L in the formula (1) of the present invention represents the number of repeating units of monodisperse polyethylene glycol, and is an integer of 2 to 72, preferably an integer of 3 to 36, more preferably an integer of 4 to 24, and particularly preferably an integer of 6 to 12. Also, l is preferably l.ltoreq.n, more preferably l.ltoreq.2 n/3.

In the present specification, the atomic group X in the formula (1)¹And Y¹Different from each other and not particularly limited as long as it is an atomic group containing at least one functional group capable of forming a covalent bond by reaction with a functional group present in a biofunctional molecule (for example, a physiologically active protein, a peptide, an antibody, a nucleic acid, or a low-molecular-weight drug) to be modified with the hetero-bifunctional monodisperse polyethylene glycol. Examples of functional groups include, for example, those described in "Hermanson, g.t. bioconjugate Techniques,2 nd; academic Press: San Diego, CA,2008 "," Harris, J.M.Poly (Ethylene Glycol) Chemistry; plenum Press, New York,1992 "and" PEGylated Protein Drugs, Basic science and Clinical Applications; veronese, f.m., ed.; birkhauser: Basel, Switzerland,2009 ", et al.

Wherein, X¹And Y¹The functional groups included are each independently preferably a functional group capable of reacting with a functional group (e.g., amino group, thiol group, aldehyde group, or carboxyl group) present in a natural biofunctional molecule represented by a protein or a functional group (e.g., maleimide group, ketone group, azide group, or alkyne group) artificially introduced into the biofunctional molecule under mild reaction conditions with high reaction efficiency. More specifically, it is preferably a reactive ester group, a reactive carbonate group, an aldehyde group, an isonitrile ester group, an isothiocyanate group, an epoxy group, a maleimide group, a vinyl sulfone group, an acryloyl group, a sulfonyloxy group, a carboxyl group, a mercapto group, a 2-pyridyldithio group, an α -haloacetyl group, a hydroxyl group, an alkynyl group, an allyl group, a vinyl group, an amino group, an oxo amino group, a hydrazide group, an azide group or an isocyanate groupDibenzocyclooctyne (DBCO) group. In addition, it is preferably an activated ester group, an activated carbonate group, a maleimide group, an α -haloacetyl group, an alkynyl group, an azido group or a Dibenzocyclooctyne (DBCO) group in view of reaction efficiency.

More specifically, X¹And Y¹The functional groups contained are each independently, and when the functional group present in the biofunctional molecule to be modified is an amino group, it is preferably an active ester group, an active carbonate group, an aldehyde group, an isocyanate group, an isothiocyanate group, an epoxy group, a maleimide group, a vinyl sulfone group, an acryloyl group, an α -haloacetyl group, a sulfonyloxy group, or a carboxyl group; in the case where the functional group present in the biofunctional molecule to be modified is a mercapto group, it is preferably an active ester group, an active carbonate group, an aldehyde group, an isonitrile ester group, an isothiocyanate group, an epoxy group, a maleimide group, a vinyl sulfone group, an acryloyl group, a sulfonyloxy group, a carboxyl group, a mercapto group, a 2-pyridyldithio group, an α -haloacetyl group, an alkynyl group, an allyl group or a vinyl group; when the functional group present in the biofunctional molecule to be modified is a carboxyl group, it is preferably a mercapto group, a hydroxyl group, an amino group, an oxoamino group or a hydrazide group; when the functional group present in the biofunctional molecule to be modified is an alkynyl group, it is preferably a mercapto group, an amino group, an oxyamino group, a hydrazide group or an azide group; when the functional group present in the biofunctional molecule to be modified is an azide group, it is preferably an alkynyl group or a Dibenzocyclooctyne (DBCO) group; when the functional group present in the biofunctional molecule to be modified is a haloalkyl group, an alkylsulfonate or an arylsulfonate, a mercapto group, a hydroxyl group or an amino group is preferable.

Here, "active ester group" refers to a group represented by the formula: -C (═ O) -L, wherein L represents a leaving group. The leaving group represented by L includes succinimidyloxy, phthalimidyloxy, 4-nitrophenoxy, 1-imidazolyl, pentafluorophenoxy, benzotriazol-1-yloxy, and 7-azabenzotriazol-1-yl-oxy, and the like. "activated carbonate" refers to a polycarbonate represented by the formula: an activated carbonate group represented by-O-C (═ O) -L, and L represents the same leaving group as described above.

In a preferred embodiment of the invention, X¹And Y¹Each independently is a group represented by group (I), group (II), group (III), group (IV), group (V) or group (VI).

Group (I): functional groups capable of forming covalent bonds by reaction with amino groups of biofunctional molecules

The following (a), (b1), (b2), (c), (d), (e) and (f):

group (II): functional groups capable of forming covalent bonds by reaction with thiol groups of biofunctional molecules

The following (a), (b1), (b2), (c), (d), (e), (f), (g), (h) and (l):

group (III): functional groups capable of forming covalent bonds by reaction with aldehyde or carboxyl groups of biofunctional molecules

The following (g), (i), (j), (k), and (o):

group (IV): functional groups capable of forming covalent bonds by reaction with alkynyl groups of biofunctional molecules

The following (g), (i), (j), (k) and (n):

a group (V): functional groups capable of forming covalent bonds by reaction with the azido groups of biofunctional molecules

The following (l) and (m):

group (VI): functional groups capable of forming covalent bonds by reaction with haloalkyl, alkylsulfonate or arylsulfonate groups of a biofunctional molecule

The following (g), (i) and (o).

In a preferred embodiment of the invention, X¹And Y¹Each independently is particularly preferably a radical (a) to (n).

In the formula, R²And R⁴Each is a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms, examples of the hydrocarbon group include alkyl groups, and the hydrocarbon group specifically includes methyl, ethyl, propyl, isopropyl, butyl, tert-butyl and pentyl groups。R³Is a halogen atom selected from a chlorine atom, a bromine atom and an iodine atom.

As the radical X in the formula (1)¹And Y¹Preferred combinations of functional groups are included when X¹When the functional group contained is a reactive ester group or a reactive carbonate group, Y¹The functional group contained is a group selected from the group consisting of a maleimide group, a vinylsulfone group, an α -haloacetyl group, an alkynyl group, a Dibenzocyclooctyne (DBCO) group and an azide group; when X is present¹When the functional group contained is an aldehyde group, Y¹The functional group contained is a group selected from a maleimide group, a vinylsulfone group, an alkynyl group, a Dibenzocyclooctyne (DBCO) group and an azide group; when X is present¹Y when the functional group is a maleimide group, a vinylsulfone group or an alpha-haloacetyl group¹The functional group included is a group selected from the group consisting of an activated ester group, an activated carbonate group, an alkynyl group, a Dibenzocyclooctyne (DBCO) group, and an azido group; when X is present¹When the functional group is an alkynyl group, a Dibenzocyclooctyne (DBCO) group or an azido group, Y¹The functional group contained is a group selected from the group consisting of a maleimide group, a vinylsulfone group, an α -haloacetyl group, an active ester group, an active carbonate group, an amino group, an oxyamino group and a hydroxyl group; when X is present¹When the functional group contained is amino or oxo-amino, Y¹The functional group contained is alkynyl, Dibenzocyclooctyne (DBCO) group, azido, sulfhydryl, hydroxyl or carboxyl; and when X¹When the functional group contained is mercapto, 2-pyridyldithio or hydroxy, Y¹Is a group selected from amino, oxo-amino, azido and carboxyl. More preferably, when X¹When the functional group contained is a reactive ester group or a reactive carbonate group, Y¹The functional group contained is a group selected from the group consisting of a maleimide group, an α -haloacetyl group, an alkynyl group, a Dibenzocyclooctyne (DBCO) group and an azido group; when X is present¹When the functional group contained is an aldehyde group, Y¹The functional group contained is a group selected from the group consisting of a maleimide group, an α -haloacetyl group, an alkynyl group, a Dibenzocyclooctyne (DBCO) group and an azido group; when X is present¹When the functional group is a maleimide group or an alpha-haloacetyl group, Y¹Bag (a bag)The functional group is a group selected from the group consisting of an activated ester group, an activated carbonate group, an alkynyl group, a Dibenzocyclooctyne (DBCO) group and an azido group; when X is present¹When the functional group is an alkynyl group, a Dibenzocyclooctyne (DBCO) group or an azido group, Y¹The functional group contained is a group selected from the group consisting of a maleimido group, an α -haloacetyl group, an activated ester group, an activated carbonate group, an amino group, an oxo-amino group and a hydroxyl group; when X is present¹When the functional group contained is amino or oxo-amino, Y¹The functional group contained is alkynyl, Dibenzocyclooctyne (DBCO) group, azido, hydroxyl or sulfhydryl; and when X¹When the functional group contained is mercapto, 2-pyridyldithio or hydroxy, Y¹The functional groups included are groups selected from amino, oxo-amino and azido groups.

A in the formula (1) of the present invention¹Is a quaternary carbon atom of the branched moiety and is bound to X¹A divalent spacer between monodisperse polyethylene glycols of formula (1), B¹Is a quaternary carbon atom of the branching moiety with Y¹A divalent spacer therebetween, C in formula (1)¹Is bound to A¹Monodisperse polyethylene glycol of (A) and (B)¹And each of them is composed of a covalent bond. Specifically, A¹Is represented by-L¹-(CH₂)_m1-or-L¹-(CH₂)_m1-L²-(CH₂)_m2-，L¹Represents an ether bond, an amide bond, a urethane bond, a secondary amino group or a single bond, L²Represents an amide bond or a urethane bond, and m1 and m2 each independently represent an integer of 1 to 5. B is¹Is represented by-L³-(CH₂)_m3-、-L³-(CH₂)_m3-L⁴-(CH₂)_m4-or a single bond, L³Represents an amide bond or a single bond, L⁴Represents an ether bond, an amide bond or a urethane bond, and m3 and m4 each independently represent an integer of 1 to 5. C¹Is represented by-L⁵-(CH₂)_m5-、-O-CH₂-or a single bond, L⁵Represents an amide bond, a urethane bond, a secondary amino group or a single bond, and m5 represents an integer of 1 to 5.

In a preferred embodiment of the present invention, A in the formula (1)¹、B¹And C¹And has the above-mentioned A¹、B¹And C¹Typical synthesis examples of the heterobifunctional monodisperse polyethylene glycol of (a) will be described below, but the present invention should not be construed as being limited thereto.

(A) In a preferred embodiment of the present invention, A in the formula (1)¹represents-NHC (O) - (CH)₂)_m1-or-NHC (O) - (CH)₂)_m1-L²-(CH₂)_m2-，L²Is an amide bond or a urethane bond, and m1 and m2 each independently represent an integer of 1 to 5; b is¹Is represented by- (CH)₂)_m3-or- (CH)₂)_m3-L⁴-(CH₂)_m4-，L⁴Is an ether bond, an amide bond or a urethane bond, and m3 and m4 each independently represent an integer of 1 to 5; c¹Is represented by-L⁵-(CH₂)_m5-、-O-CH₂-or a single bond, L⁵Is an amide bond, a urethane bond, a secondary amino group or a single bond, and m5 represents an integer of 1 to 5. More preferably, A¹represents-NHC (O) - (CH)₂)_m1-, and m1 represents an integer of 1 to 5; b is¹Is represented by- (CH)₂)_m3-or- (CH)₂)_m3-O-(CH₂)_m4And m3 and m4 each independently represent an integer of 1 to 5; c¹represents-NHC (O) - (CH)₂)_m5-or a single bond, and m5 represents an integer from 1 to 5.

A typical example of the synthesis of the above heterobifunctional monodisperse polyethylene glycol comprises the following steps. Here, compounds in which a maleimide group and a p-nitrophenyl carbonate group are introduced as functional groups are exemplified.

(in the formula (3), P¹Is a protecting group for amino groups, and P²Is a protecting group for a hydroxyl group. )

Nucleophilic displacement reaction of the compound represented by formula (3) with an alkyl or aryl sulfonate of monomethyl monodisperse polyethylene glycol or a halide of monomethyl monodisperse polyethylene glycol in an anhydrous solvent in the presence of a strong base to obtain a compound represented by the following formula (4).

As used herein, a "protecting group" is a moiety that prevents or hinders the reaction of a particular functional group in a molecule under certain reaction conditions. The protecting group will vary depending on the type of functional group to be protected, the conditions of use, and the presence of other functional groups or protecting groups in the molecule. Specific examples of protecting groups can be found in many common books, and are described, for example, in "Wuts, p.g.m.; greene, T.W.protective Groups in Organic Synthesis,4th ed.; Wiley-Interscience, New York,2007 ". In addition, for the functional group protected by a protecting group, the original functional group can be regenerated by deprotection using reaction conditions suitable for various protecting groups, that is, by the occurrence of a chemical reaction. Typical deprotection conditions for protecting groups are described in the above documents.

As a preferable combination of the functional group to be protected and the protecting group, when the functional group to be protected is an amino group, for example, an acyl-based protecting group and a urethane-based protecting group are exemplified, and specific examples thereof include trifluoroacetyl group, 9-fluorenylmethoxycarbonyl group and 2- (trimethylsilyl) ethoxycarbonyl group. When the functional group to be protected is a hydroxyl group, for example, a silyl-based protecting group and an acyl-based protecting group are exemplified, and specific examples thereof include t-butyldiphenylsilyl, t-butyldimethylsilyl, triisopropylsilyl, acetyl and pivaloyl.

When the functional group to be protected is a carboxyl group, for example, an alkyl ester-based protecting group and a silyl ester-based protecting group are exemplified, and specific examples thereof include a methyl group, a 9-fluorenylmethyl group and a tert-butyldimethylsilyl group. When the functional group to be protected is a sulfonyl group, for example, a thioether-based protecting group, a thiocarbonate-based protecting group and a disulfide-based protecting group are exemplified, and specific examples thereof include S-2, 4-dinitrophenyl group, S-9-fluorenylmethoxycarbonyl group and S-t-butyldisulfide group. In addition, bifunctional protecting groups capable of simultaneously protecting two functional groups of the same type or different types may be used. As a preferable combination of the functional group to be protected and the protecting group, when the functional group to be protected is two hydroxyl groups, for example, a cyclic acetal-based protecting group and a cyclic silyl-based protecting group are mentioned, and specific examples thereof include 2, 2-dimethyl-1, 3-dioxolanyl, 2-dimethyl-1, 3-dioxanyl, 2-phenyl-1, 3-dioxolanyl, 2-phenyl-1, 3-dioxanyl and di-t-butylsilylene. When the functional group to be protected is an amino group and a hydroxyl group, for example, an oxazoline-based protecting group is exemplified, and specific examples thereof include a 2-phenyloxazoline group.

Typical deprotection conditions for the protecting groups are described in the above documents and reaction conditions suitable for each protecting group can be selected. However, in the case where the functional group included in the structure is a functional group that does not inhibit chemical reactions of other functional groups even when the functional group is not protected by a protecting group, it is not necessary to use a protecting group.

Protecting group P of the compound represented by the above formula (4) at deprotection¹Thereafter, the resulting compound is reacted with maleimidopropionic acid amide of monocarboxyl monodisperse polyethylene glycol in the presence of a condensing agent to obtain a compound represented by the following formula (5). Here, when the reaction conditions are selected such that the hydroxyl group does not react with the reactive agent for amino group, the protecting group P²Can be reacted with a protecting group P¹And deprotection is carried out simultaneously.

Protecting group P of the compound represented by the above formula (5) at deprotection²Thereafter, the resulting compound is reacted with p-nitrophenyl chloroformate in the presence of a base to obtain a compound represented by the following formula (6).

(B) In another preferred embodiment of the present invention, A in the formula (1)¹represents-CH₂-or-CH₂-L²-(CH₂)_m2-，L²Is an amide bond or a urethane bond, and m2 represents an integer of 1 to 5; b is¹represents-CH₂-or-CH₂-L⁴-(CH₂)_m4-，L⁴Is an ether bond, an amide bond or a urethane bond, and m4 represents an integer of 1 to 5; c¹Is represented by-L⁵-(CH₂)_m5-、-O-CH₂-or a single bond, L⁵Is an amide bond, a urethane bond, a secondary amino group or a single bond, and m5 represents an integer of 1 to 5. More preferably, A¹represents-CH₂-NHC(O)-(CH₂)_m2-, and m2 represents an integer of 1 to 5; b is¹represents-CH₂-or-CH₂-O-(CH₂)_m4-, and m4 represents an integer of 1 to 5; c¹represents-NHC (O) - (CH)₂)_m5-or a single bond, and m5 represents an integer from 1 to 5.

A typical example of the synthesis of the above heterobifunctional monodisperse polyethylene glycol comprises the following steps. Here, a compound having a bromoacetamido group and an N-succinimidyl ester group introduced as functional groups is exemplified.

(in the formula (7), P³Is a protecting group for amino groups, and P⁴Is a protecting group for a hydroxyl group. )

The compound represented by the above formula (7) is subjected to nucleophilic displacement reaction with an alkyl or aryl sulfonate of monomethyl monodisperse polyethylene glycol or a halide of monomethyl monodisperse polyethylene glycol in an anhydrous solvent in the presence of a strong base to obtain a compound represented by the following formula (8).

Protecting group P of the compound represented by the above formula (8) at deprotection⁴Thereafter, the resulting compound is reacted with a carboxyl group protector of 4-hydroxybutyric acid in an anhydrous solvent in the presence of a base to obtain a compound represented by the following formula (9).

(in the formula, P⁵Is a protecting group for a carboxyl group. )

Protecting group P of the compound represented by the above formula (9) at deprotection³Thereafter, the resulting compound was reacted with tetrafluorophenyl ester of monobromoacetamide monodisperse polyethylene glycol to obtain a compound represented by the following formula (10).

Protecting group P of the compound represented by the above formula (10) at deprotection⁵Thereafter, the resulting compound is reacted with N-hydroxysuccinimide in the presence of a condensing agent to obtain a compound represented by the following formula (11).

(C) In still another preferred embodiment of the present invention, A in the formula (1)¹represents-O- (CH)₂)_m1-or-O- (CH)₂)_m1-L²-(CH₂)_m2-，L²Is an amide bond or a urethane bond, and m1 and m2 each independently represent an integer of 1 to 5; b is¹represents-CH₂-or-CH₂-L⁴-(CH₂)_m4-，L⁴Is an ether bond, an amide bond or a urethane bond, and m4 represents an integer of 1 to 5; c¹Is represented by-L⁵-(CH₂)_m5-、-O-CH₂-or a single bond, L⁵Is an amide bond, a urethane bond, a secondary amino group or a single bond, and m5 representsAn integer of 1 to 5. More preferably, A¹represents-O- (CH)₂)_m1-NHC(O)-(CH₂)_m2-, m1 and m2 each independently represent an integer of 1 to 5; b is¹represents-CH₂-or-CH₂-O-(CH₂)_m4-, and m4 represents an integer of 1 to 5; c¹represents-NHC (O) - (CH)₂)_m5-or a single bond, and m5 represents an integer from 1 to 5.

A typical example of the synthesis of the above heterobifunctional monodisperse polyethylene glycol comprises the following steps. Here, compounds having 2-pyridyldithio group and N-succinimidyl carbonate group introduced as functional groups are exemplified.

(in formula (12), P⁶Is a protecting group for amino groups, and P⁷Is a protecting group for a hydroxyl group. )

The compound represented by the above formula (12) is subjected to nucleophilic displacement reaction with an alkyl or aryl sulfonate of monomethyl monodisperse polyethylene glycol or a halide of monomethyl monodisperse polyethylene glycol in an anhydrous solvent in the presence of a strong base to obtain a compound represented by the following formula (13).

Protecting group P of the compound represented by the above formula (13) at deprotection⁶Thereafter, the resulting compound is reacted with 3- (2-pyridyldithio) propionamide of monocarboxy monodisperse polyethylene glycol in the presence of a condensing agent to obtain a compound represented by the following formula (14).

Protecting group P of the compound represented by the above formula (14) at deprotection⁷Then, the resulting compound is reacted with N, N' -disuccinimidyl carbonate in the presence of a base to obtain a compound represented by the following formula (15).

(D) In still another preferred embodiment of the present invention, A in the formula (1)¹represents-C (O) NH- (CH)₂)_m1-or-C (O) NH- (CH)₂)_m1-L²-(CH₂)_m2-，L²Is an amide bond or a urethane bond, and m1 and m2 each independently represent an integer of 1 to 5; b is¹represents-CH₂-or-CH₂-L⁴-(CH₂)_m4-，L⁴Is an ether bond, an amide bond or a urethane bond, and m4 represents an integer of 1 to 5; c¹Is represented by-L⁵-(CH₂)_m5-、-O-CH₂-or a single bond, L⁵Is an amide bond, a urethane bond, a secondary amino group or a single bond, and m5 represents an integer of 1 to 5. More preferably, A¹represents-C (O) NH- (CH)₂)_m1-, and m1 represents an integer of 1 to 5; b is¹represents-CH₂-or-CH₂-O-(CH₂)_m4-, and m4 represents an integer of 1 to 5; c¹represents-C (O) NH- (CH)₂)_m5-or a single bond, and m5 represents an integer from 1 to 5.

A typical example of the synthesis of the above heterobifunctional monodisperse polyethylene glycol comprises the following steps. Here, a compound in which an azido group and a p-nitrophenyl carbonate group are introduced as functional groups is exemplified.

(in the formula (16), P⁸Is a protecting group for a carboxyl group, and P⁹Is a protecting group for a hydroxyl group. )

Subjecting the compound represented by formula (16) to a nucleophilic displacement reaction with an alkyl or aryl sulfonate of monomethyl monodisperse polyethylene glycol or a halide of monomethyl monodisperse polyethylene glycol in an anhydrous solvent in the presence of a strong base to obtain a compound represented by the following formula (17).

Protecting group P of the compound represented by the above formula (17) at deprotection⁸Thereafter, the resulting compound is reacted with azide of monoamino monodisperse polyethylene glycol in the presence of a condensing agent to obtain a compound represented by the following formula (18).

Protecting group P of the compound represented by the above formula (18) at deprotection⁹Thereafter, the resulting compound was reacted with p-nitrophenyl chloroformate in the presence of a base to obtain a compound represented by the following formula (19).

(E) In still another preferred embodiment of the present invention, A in the formula (1)¹represents-C (O) NH- (CH)₂)_m1-or-C (O) NH- (CH)₂)_m1-L²-(CH₂)_m2-，L²Is an amide bond or a urethane bond, and m1 and m2 each independently represent an integer of 1 to 5; b is¹represents-C (O) NH- (CH)₂)_m3-or-C (O) NH- (CH)₂)_m3-L⁴-(CH₂)_m4-，L⁴Is an ether bond, an amide bond or a urethane bond, and m3 and m4 each independently represent an integer of 1 to 5; c¹Is represented by-L⁵-(CH₂)_m5-、-O-CH₂-or a single bond, L⁵Is an ether bond, an amide bond, a urethane bond, a secondary amino group or a single bond, and m5 represents an integer of 1 to 5. More preferably, A¹represents-C (O) NH- (CH)₂)_m1-, and m1 represents an integer of 1 to 5; b is¹represents-C (O) NH- (CH)₂)_m3-NHC(O)-(CH₂)_m4And m3 and m4 each independently represent an integer of 1 to 5; c¹represents-C (O) NH- (CH)₂)_m5-or a single bond, and m5 represents an integer from 1 to 5.

A typical example of the synthesis of the above heterobifunctional monodisperse polyethylene glycol comprises the following steps. Here, a compound in which a Dibenzocyclooctyne (DBCO) group and a maleimide group are introduced as functional groups is exemplified.

(in formula (20), P¹⁰Is a protecting group for a carboxyl group, and P¹¹Is a protecting group for an amino group. )

The compound represented by the above formula (20) is subjected to nucleophilic displacement reaction with an alkyl or aryl sulfonate of monomethyl monodisperse polyethylene glycol or a halide of monomethyl monodisperse polyethylene glycol in an anhydrous solvent in the presence of a strong base to obtain a compound represented by the following formula (21).

Protecting group P of the compound represented by the above formula (21) at deprotection¹⁰Then, the resulting compound is reacted with a Dibenzocyclooctyne (DBCO) based derivative of monoamino monodisperse polyethylene glycol in the presence of a condensing agent to obtain a compound represented by the following formula (22).

Protecting group P of the compound represented by the above formula (22) at deprotection¹¹Thereafter, the resulting compound was reacted with 3-maleimidopropionic acid N-succinimidyl ester to obtain a compound represented by the following formula (23).

According to another aspect of the present invention, there is provided an antibody-drug conjugate comprising heterobifunctional monodisperse polyethylene glycol represented by formula (2).

R in the formula (2) of the present invention¹Is a hydrocarbon group or a hydrogen atom. The number of carbon atoms of the hydrocarbon group is preferably 7 or less. Examples of the hydrocarbon group include alkyl groups, aryl groups and aralkyl groups, and the hydrocarbon group specifically includes methyl groups, ethyl groups, propyl groups, isopropyl groups, tert-butyl groups, phenyl groups and benzyl groups. R¹Is a methyl group or a hydrogen atom, more preferably a methyl group.

N in formula (2) of the present invention represents the number of repeating units of monodisperse polyethylene glycol, and is an integer of 3 to 72, preferably an integer of 4 to 48, more preferably an integer of 6 to 36, and particularly preferably an integer of 8 to 24.

L in the formula (2) of the present invention represents the number of repeating units of monodisperse polyethylene glycol, and is an integer of 2 to 72, preferably an integer of 3 to 36, more preferably an integer of 4 to 24, and particularly preferably an integer of 6 to 12. Also, l is preferably l.ltoreq.n, more preferably l.ltoreq.2 n/3.

In the present specification, X in the formula (2)²And Y²One is an antibody and the other is a drug.

The term "antibody" in the present specification is used in its broadest sense and specifically includes monoclonal antibodies, polyclonal antibodies, dimers, multimers, multispecific antibodies (e.g., bispecific antibodies), and antibody fragments, so long as they exhibit the desired biological activity (Miller, k.et al.j. immunol.2003,170, 4854-4861).

The antibody may be a murine antibody, a human antibody, a humanized antibody, or a chimeric antibody, or can be derived from other species. Antibodies are proteins produced by the immune system that are capable of recognizing and binding to specific antigens (Janeway, C.; Travers, P.; Walport, M.; Shlomchik, M. immunobiology,5th ed.; Garland Publishing: New York, 2001). The antigen of interest typically has multiple binding sites (also referred to as epitopes) that are recognized by the CDRs of multiple antibodies. Antibodies that specifically bind to different epitopes have different structures. Thus, an antigen may have more than one corresponding antibody. Antibodies include full-length immunoglobulin molecules or immunologically active portions of full-length immunoglobulin molecules (i.e., molecules that comprise an antigen binding site that immunospecifically binds to an antigen of interest or a portion thereof). Such targets include, but are not limited to, cancer cells and cells that produce autoimmune antibodies associated with autoimmune diseases. The immunoglobulin disclosed in the present specification may be of any type (e.g., IgG, IgE, IgM, IgD or IgA), class (class) of immunoglobulin (e.g., IgG1, IgG2, IgG3, IgG4, IgA1 or IgA2), or subclass thereof. The immunoglobulin may be derived from any species. However, in one embodiment, the immunoglobulin is of human, murine or rabbit origin.

Polyclonal antibodies are heterogeneous groups of antibody molecules, e.g., derived from the serum of an immunized animal. Polyclonal antibodies to the antigen of interest can be generated by using a variety of methods known in the art. For example, to produce polyclonal antibodies, various host animals including, but not limited to, rabbits, mice, rats, and guinea pigs, may be immunized by injection with the antibody or derivative thereof of interest. Depending on the species of the host, the immune response may be increased by using various adjuvants including, but not limited to, freund's (complete and incomplete), mineral gels such as aluminum hydroxide, surfactant substances such as lysolecithin, polyols (pluronic polyols), polyanions, peptides, oil emulsions, keyhole limpet hemocyanin, dinitrophenol, and potentially useful human adjuvants such as BCG (bacillus Calmett-Guerin) or cryptosporidium parvum (Corynebacterium parvum). Such adjuvants are also known in the art.

Monoclonal antibodies are homogeneous groups of antibodies of specific antigenic determinants, such as cellular antigens (cancer or autoimmune cell antigens), viral antigens, microbial antigens, proteins, peptides, carbohydrates, chemicals, nucleic acids, or antigen-binding fragments thereof. Monoclonal antibodies (mabs) to the antigen of interest may be generated by using any technique known in the art. Including but not limited to Kohler, G; the hybridoma technology originally described in Milstein, C.Nature 1975,256,495-497, the human B-cell hybridoma technology (Kozbor, D.et al. Immunol. today 1983,4,72-79) and the EBV-hybridoma technology (Cole, S.P.C.et al. monoclonal Antibodies and Cancer Therapy; Alan R.Liss: New York,1985, pp.77-96). Such antibodies may be of any immunoglobulin class, including IgG, IgM, IgE, IgA, and IgD, and any subclass thereof. Hybridomas producing monoclonal antibodies of the invention can be cultured in vitro (in vitro) or in vivo (in vivo).

Monoclonal antibodies include, but are not limited to, human monoclonal antibodies, humanized monoclonal antibodies, chimeric monoclonal antibodies, and antibody fragments. Human monoclonal antibodies can be made by any of a variety of techniques known in the art (see, e.g., Teng, N.N.et al Proc. Natl. Acad. Sci. USA.1983,80, 7308-. Recombinant antibodies, such as chimeric or humanized monoclonal antibodies, can be made by standard recombinant DNA techniques known in the art (see, e.g., U.S. Pat. nos. 4,816,567 and 4,816,397).

The immunogenicity of antibodies can also be reduced by surface reconstitution (resurfacing) treatment of the antibodies (see, e.g., U.S. Pat. No. 5,225,539 and european patent nos. 0239400, 0519596 and 0592106).

In one embodiment of the invention, the antibody may be a bispecific antibody. Methods of making bispecific antibodies are known in the art. Conventional methods for making full-length bispecific antibodies utilize the simultaneous expression of two immunoglobulin heavy-light chain pairs with different specificities for both chains (see Milstein, C.et al. Nature 1983,305, 537-539). According to different approaches, bispecific antibodies can also be produced by fusing antibody variable domains (antibody-antigen binding sites) with the desired binding specificity with immunoglobulin constant domain sequences.

Other useful antibodies include fragments of antibodies, but are not limited to, F (ab ') 2 fragments, Fab' fragments, Fab fragments, Fvs, Single Chain Antibodies (SCAs) (e.g., as described in U.S. Pat. Nos. 4,946,778, Bird, R.E.et al science 1988,242,423 + 442, Huston, J.S.et al Proc.Natl.Acad.Sot USA 1988,85,5879 + 5883 and Ward, E.S.et al Nature 1989,334,544 + 554), scFv, sc-Fv-Fc, FvdsFvdsFfv, minibody (minibody), diabody, triabody, tetrabody, and any other molecule that contains a CDR and has the same specificity as an antibody, such as a domain antibody.

In a preferred embodiment of the present invention, known antibodies for treating or preventing cancer may be used. All target proteins, including any target protein whose expression is associated with expression in cells of a cancer, cell proliferation disorder, or tumor, can serve as targets for antibodies.

In a preferred embodiment of the invention, the antibodies are useful for the treatment of cancer. Examples of antibodies useful in the treatment of cancer include, but are not limited to: rituxan (Rituxan) (registered trademark) (Genentech Inc.), a chimeric anti-CD 20 monoclonal antibody for use in treating patients with non-Hodgkin's lymphoma; OvaRex (AltaRex Corp.), a murine antibody for the treatment of ovarian cancer; panorex (Glaxo wellcomelnc), which is a murine IgG2a antibody for the treatment of colorectal cancer; cetuximab ERBITUX (ImClone systesinc), an anti-EGFR IgG chimeric antibody for the treatment of epidermal growth factor positive cancers such as head or neck cancer; vitaxin (MedImmune Inc.), a humanized antibody for the treatment of sarcoma; campath I/H (leukositelnc), which is a humanized IgG1 antibody for the treatment of Chronic Lymphocytic Leukemia (CLL); smart M195 (protein design Labs Inc.), a humanized anti-CD 33 IgG antibody for the treatment of Acute Myeloid Leukemia (AML); lymphocide (Immunodics Inc.), a humanized anti-CD 22 IgG antibody for the treatment of non-Hodgkin lymphoma; smart ID 10(Protein Design Labs Inc.), a humanized anti-HLA-DR antibody for the treatment of non-Hodgkin's lymphoma; oncolym (Techniclone Inc.), a radiolabeled murine anti-HLA-Dr 10 antibody for the treatment of non-Hodgkin's lymphoma; AlloMune (BioTransplant Inc.), a humanized anti-CD 2 mAb used to treat Hodgkin's disease or non-Hodgkin's lymphoma; avastin (GenentechInc.), an anti-VEGF humanized antibody for the treatment of lung or colorectal cancer; epratuzamab (immunology Inc. and Amgen Inc.), an anti-CD 22 antibody for the treatment of non-Hodgkin lymphoma; and CEAcide (immunolamedics Inc.), a humanized anti-CEA antibody for the treatment of colorectal cancer.

In a preferred embodiment of the invention, the antibody is an antibody to the following antigens: CA125, CA15-3, CA19-9, L6, Lewis Y, Lewis X, alpha fetoprotein, CA242, placental alkaline phosphatase, prostate specific membrane antigen, Ephb2, TMEFF2, prostatic acid phosphatase, epidermal growth factor, MAGE-1, MAGE-2, MAGE-3, MAGE-4, transferrin receptor, P97, MUC1-KLH, CEA, gp 100, MART 1, prostate specific antigen, IL-2 receptor, CD20, CD52, CD33, CD22, human chorionic gonadotropin, CD38, CD40, mucin, P21, MPG, and Neu oncogene products. Some specific useful antibodies include, but are not limited to: mAbs to CD40 antigens, such as BR96 mAb (Trail, P.A.et al.science 1993,261,212-215), BR64(Trail, P.A.et al.cancer Research 1997,57,100-105) or S2C 6mAb (Francisco, J.A.et al.cancer Res.2000,60, 3225-3231); or other anti-CD 40 antibodies, such as those disclosed in U.S. patent application publication nos. 2003/0211100 and 2002/0142358; mabs to CD70 antigen, such as 1F6mAb and 2F2 mAb; and mAbs to the CD30 antigen, such as AC10(Bowen, M.A.et al.J.Immunol.1993,151,5896-5906, Wahl, A.F.et al.cancer Res.2002,62(13), 3736-za 3742) or MDX-0060 (U.S. patent application publication No. 2004/0006215).

Drugs that can be used in the present invention include chemotherapeutic agents. Chemotherapeutic agents are compounds useful in the treatment of cancer. Examples of chemotherapeutic agents include the following: alkylating agents, such as thiotepa (thiotepa) and cyclophosphamide (cyclophosphamide) (CYTOXAN (trademark)); alkyl sulfonates such as busulfan, improsulfan and piposulfan; aziridines, such as benzotepa, carboquone, metoclopramide and uretepa; ethyleneamines and methylmelamines, including altretamine, triethylenemelamine, triethylenephosphoramide, triethylenethiophosphoramide, and trimethylolmelamine; annonaceous acetogenins (especially bullatacin and bullatacin), camptothecins (including the synthetic analogue topotecan), bryostatins (bryostatin), callystatins (CC-1065) including adozelesin (adozelesin), cazelesin (carzelesin) and bizelesin (bizelesin) synthetic analogues thereof, cryptophycins (especially cryptophycins 1 and cryptophycins 8), dolastatins (dolastatins), duocarmycins (including the synthetic analogues KW-2189 and CB 1-1), elsinolobins (elutherobin), canines (panoxanthins), saratins (palmatins), sarcinostatin (spinosyns), cystatins (including the synthetic analogues KW-2189 and CB 78-1), elsinolide (elsinolide), isophane hydrochloride (diethylcarbamazepine), isophane hydrochloride (diethyltoluamide hydrochloride), isophane hydrochloride (isophane hydrochloride), isophane hydrochloride (isophane, isophane hydrochloride), isophane hydrochloride (isophane hydrochloride), isophane hydrochloride (isophane, isophane, Benzene mustard cholesterol (pherenesterone), prednimustine (prednimustine), trofosfamide (trofosfamide), and uracil mustard (uracil musard); nitrosoureas such as carmustine (carmustine), meglumine (chlorzotocin), fotemustine (fotemustine), lomustine (lomustine), nimustine (nimustine) and ramustine (ranirnustine); antibiotics such as enediynes (enediynes) antibiotics (e.g., calicheamicin, particularly calicheamicin gemma 1 and calicheamicin theta I, see, e.g., Angew Chem Intl.Ed. Engl.33:183-186 (1994); dynemicin, including dynemicin A; esperamicin (esperamicin); and neocarzinostatin (neocarzinostatin) chromophores and related chromoprotein enediyne antibiotics chromophores), aclacinomycin (acrinomycin), actinomycin (actinomycin), anthranomycin (anthramycin), azaserine (azaserine), bleomycin (bleomycin), actinomycin C (cactinomycin), carbacalicheamicin, carmycin (carminomycin), carzinophilin (carzinophilin); chromomycin (chromomycin), actinomycin D (dactinomycin), daunorubicin (daunorubicin), ditorexin (detorubicin), 6-diaza-5-oxo-L-norleucine, doxorubicin (doxorubicin) (including morpholino doxorubicin, cyanomorpholino doxorubicin, 2-pyrrol doxorubicin and deoxydoxorubicin), epirubicin (epirubicin), esorubicin (esorubicin), idarubicin (idarubicin), mariomycin (mariocemycin), mitomycins (nitromycins), mycophenolic acid (mycophenolic acid), nogalamycin (nogalamycin), olivomycin (olivomycin), pelomycin (polyplomycin), potomycins (puromycin), puromycin (ferricin), streptozocin (streptozocin); metabolic antagonists such as methotrexate (methotrexate) and 5-fluorouracil (5-FU); folic acid analogs such as denopterin, methotrexate, pteropterin and trimetrexate; purine analogs such as fludarabine (fludarabine), 6-mercaptopurine, thiamiprine (thiamiprine), and thioguanine (thioguanine); pyrimidine analogs such as, for example, ancitabine (ancitabine), azacitidine (azacitidine), 6-azauridine (6-azauridine), carmofur (carmofur), cytarabine (cytarabine), dideoxyuridine (dideoxyuridine), doxifluridine (doxifluridine), enocitabine (enocitabine), floxuridine (floxuridine), and 5-FU; androgens (androgens), such as carroterone (calusterone), drostandrosterone propionate (dromostanolone propionate), epithioandrostanol (epitiostanol), mepiquat (mepiquitane), and testolactone (testolactone); anti-adrenal (anti-adrenal) species such as aminoglutethimide, mitotane and trilostane; folic acid supplements, such as folinic acid (frilic acid); acetoglucurolactone (acegultone); (ii) an aldophosphamide glycoside; aminolevulinic acid (aminolevulinic acid); amsacrine (amsacrine); amoxicillin (bestrabucil); bisantrene; edatrexate (edatraxate); defofamine; dimecorsine (demecolcine); mitoquinone (diaziquone); efluoromithine (elfosmithine); ammonium etitanium acetate; epothilone (epothilone); etoglut (etoglucid); gallium nitrate; a hydroxyurea; lentinan (lentinan); lonidamine (lonidamine); maytansinoids (maytansinoids), such as maytansinoids (maytansine) and ansamitocins (ansamitocins); mitoguazone (mitoguzone); mitoxantrone (mitoxantrone); mopidamol (mopidamol); diamine nitracridine (nitrarine); pentostatin (pentostatin); methionine mustard (phenamett); pirarubicin (pirarubicin); podophyllinic acid (podophyllinic acid); 2-ethyl hydrazide; procarbazine (procarbazine); PSK (registered trademark); razoxane (rizoxane); rhizoxin (rhizoxin); sizofuran (sizofiran); germanium spiroamines (spirogyranium); tenuazonic acid (tenuazonic acid); triimine quinone (triaziquone); 2,2' -trichlorotriethylamine; trichothecenes (trichothecenes) (in particular, T-2 toxin, verrucin a (verrucin a), tuberculin a (roridin a) and snakes (anguidine)); urethane (urethane); vindesine (vindesine); dacarbazine (dacarbazine); mannomustine (mannomustine); dibromomannitol (mitobronitol); dibromodulcitol (mitolactol); pipobromane (pipobroman); a polycytidysine; cytarabine (Ara-C); cyclophosphamide; thiotepa; taxanes (taxoids) such as paclitaxel (paclitaxel) (TAXOL (registered trademark), Bristol-Myers Squibb Oncology) and docetaxel (doxetaxel) (TAXOTERE (registered trademark), Rhone-Poulenc ror); chlorambucil (chlorambucil); gemcitabine (gemcitabine); 6-thioguanine (6-thioguanine); mercaptopurine; methotrexate; platinum analogs, such as cisplatin (cissplatin) and carboplatin (carboplatin); vinblastine (vinblastine); platinum; etoposide (VP-16); ifosfamide; mitomycin c (mitomycin c); mitoxantrone (mitoxantrone); vincristine (vincristine); vinorelbine (vinorelbine); navelbine (navelbine); noxiatrone (novantrone); teniposide (teniposide); daunomycin (daunomycin); aminopterin (aminopterin); (xiloda); ibandronate (ibandronate); CPT-11; topoisomerase inhibitor RFS 2000; difluoromethyl ornithine (DMFO); retinoic acid; capecitabine (capecitabine); and pharmaceutically acceptable salts, acids or derivatives of any of the foregoing. Anti-hormonal agents, such as anti-estrogen drugs, that can act to modulate or inhibit hormonal effects on tumors, including, but not limited to, tamoxifen (tamoxifen), raloxifene (raloxifene), 4(5) -imidazole-inhibiting aromatase, 4-hydroxyttamoxifen, trioxifene (trioxifene), raloxifene hydrochloride (keoxifene), LY 117018, onapristone (onapristone), and toremifene (Fareston); and antiandrogenic drugs, for example, the following are also included in the definition: flutamide (flutamide), nilutamide (nilutamide), bicalutamide (bicalutamide), leuprolide (leuprolide), and goserelin (goserelin); siRNA, and pharmaceutically acceptable salts, acids or derivatives of any of the foregoing. Other chemotherapeutic agents that can be used in the present invention are disclosed in U.S. patent application publication nos. 2008/0171040 and 2008/0305044, the entire contents of which are incorporated herein by reference in their entirety.

In a preferred embodiment of the invention, the chemotherapeutic agent is a low molecular weight drug. The molecular weight of the low molecular weight drug is preferably 100 to 1500, more preferably 120 to 1200, and still more preferably 200 to 1000. Typically, low molecular weight drugs refer to organic, inorganic, or organometallic compounds having a molecular weight of less than about 1000, and the compounds are widely used. The low molecular weight drugs of the present invention also include oligopeptides and other biomolecules having a molecular weight of less than about 1000. Low molecular weight drugs are well known in the art, see, inter aliｃA, WO 05/058367, EP-A-85901495, EP-A-8590319, and U.S. Pat. No. 4,956,303, the entire contents of which are incorporated herein by reference in their entirety.

Preferred low molecular weight drugs of the invention are low molecular weight drugs capable of linking to antibodies. The invention includes known drugs, as well as drugs with understood possibilities. Particularly preferred low molecular weight drugs include cytotoxic agents.

Preferred cytotoxic agents include maytansinoids, CC-1065 analogs, morpholines, doxorubicin, taxanes (taxanes), cryptophycins, epothilones, calicheamicins, auristatins (auristatins), and pyrrolobenzodiazepine (pyrrobenzodiazepine) dimers.

The antibody-drug conjugate comprising heterobifunctional monodisperse polyethylene glycol represented by formula (2) of the present invention can be prepared by binding an antibody and a drug using the heterobifunctional monodisperse polyethylene glycol represented by formula (1). The antibody-drug conjugate shown in formula (2) may be prepared by a method in which the hetero-bifunctional monodisperse polyethylene glycol shown in formula (1) is first bound to the drug and then bound to the antibody, or a method in which the hetero-bifunctional monodisperse polyethylene glycol shown in formula (1) is first bound to the antibody and then bound to the drug. Further, purification may be performed after either one of the antibody and the drug is bound, or after both the antibody and the drug are bound.

The compound in which the hetero-bifunctional monodisperse polyethylene glycol represented by formula (1) is bound to the drug can be purified by a purification method such as column chromatography, extraction, recrystallization, adsorption treatment, reprecipitation or supercritical extraction. In addition, the compound in which the hetero-bifunctional monodisperse polyethylene glycol represented by formula (1) is bound to the antibody and the antibody-drug conjugate in which the hetero-bifunctional monodisperse polyethylene glycol represented by formula (1) is bound to both the antibody and the drug can be purified by a purification method such as column chromatography, extraction, or adsorption treatment.

The number of drugs bound to the antibody by the hetero bifunctional monodisperse polyethylene glycol represented by formula (1) of the present invention is defined by the average number of drugs per antibody. The amount of the drug is preferably 1 to 20, more preferably 2 to 16, still more preferably 3 to 12, and particularly preferably 4 to 8.

The amount of drug per antibody in the ADC can be determined by methods known to those skilled in the art, such as uv/vis spectroscopy, mass spectrometry, ELISA, electrophoresis, HPLC (high performance liquid chromatography) or a combination of these methods.

A in the formula (2) of the present invention¹Is a quaternary carbon atom of the branched moiety and is bound to X²A divalent spacer between monodisperse polyethylene glycols of formula (2), B²Is a quaternary carbon atom of the branching moiety with Y²A divalent spacer therebetween, and C in the formula (2)²Is bound to A¹Monodisperse polyethylene glycol of (A) and (B)²And each of them is composed of a covalent bond.

Specifically, A¹Is represented by-L¹-(CH₂)_m1-or-L¹-(CH₂)_m1-L²-(CH₂)_m2-，L¹Represents an ether bond, an amide bond, a urethane bond, a secondary amino group or a single bond, L²Represents an amide bond or a urethane bond, and m1 and m2 each independently represent an integer of 1 to 5.

In addition, B²Is represented by-L³-(CH₂)_m3-L⁶-、-L³-(CH₂)_m3-L⁴-(CH₂)_m4-L⁶-or-L⁶-，L³Represents an amide bond or a single bond, L⁴Represents an ether bond, an amide bond or a urethane bond, and m3 and m4 each independently represent an integer of 1 to 5. Here, L⁶Y in a heterobifunctional monodisperse polyethylene glycol represented by the formula (1)¹An atomic group formed by a reaction of the functional group contained with a functional group present in the antibody or the drug, and is preferably an amide bond, a urethane bond, a thioether bond, a disulfide bond, a carbonate bond, an ester bond, an ether bond, a 1H-1,2, 3-triazole-1, 4-diyl structure, a secondary amino group, a hydrazide group, an oxyamide group, or a hydrocarbon group containing any of the above.

Furthermore, C²Is represented by-L⁵-(CH₂)_m5-L⁷-、-O-CH₂-L⁷-or-L⁷-，L⁵Represents an amide bond, a urethane bond, a secondary amino group or a single bond, and m5 represents an integer of 1 to 5. Here, L⁷X in a heterobifunctional monodisperse polyethylene glycol represented by the formula (1)¹An atomic group formed by a reaction of the functional group contained with a functional group present in the antibody or the drug, and is preferably an amide bond, a urethane bond, a thioether bond, a disulfide bond, a carbonate bond, an ester bond, an ether bond, a 1H-1,2, 3-triazole-1, 4-diyl structure, a secondary amino group, a hydrazide group, an oxyamide group, or a hydrocarbon group containing any of the above.