JP2008162916A - 8-substituted guanosine derivative having hydrogen-bonding substituent and oligonucleotide containing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an 8-substituted guanosine derivative having a functional substituent at the 8-position of guanine and to provide an oligonucleotide containing the derivative. <P>SOLUTION: A method for synthesizing the 8-substituted guanosine derivative comprises a series of (1) bromination, (2) a coupling reaction of an alkylene compound using a Pd catalyst and (3) a catalytic hydrogenation step of a saccharide part under conditions of no protected hydroxy group using natural 2'-deoxyguanosine and guanosine as starting materials. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an 8-substituted guanosine derivative having a hydrogen bonding substituent at the 8-position of guanine, an oligonucleotide containing the same, and a method for producing them.

  In recent years, the in vitro selection method has attracted attention as a method of using nucleic acids using the PCR method. In the in vitro selection method, first, a large number of single-stranded nucleic acid libraries having a large number of random sequence regions are selected with specific functions by various selection systems. Subsequently, after the selected nucleic acid is amplified by PCR, the same selection is performed. By repeating this cycle, it is possible to converge to an array having a specific function. The in vitro selection method was originally developed as a method for selecting nucleic acid molecular species that specifically bind to a specific substance, and is also called Systematic Evolution of Ligands by Exponential enrichment (SELEX). Nucleic acids having binding ability obtained by this method are called aptamers, and DNA and RNA having catalytic ability such as enzymes are called deoxyribozymes and ribozymes, respectively.

Aptamers often have a specific secondary structure. They are classified into structures such as hairpins, bulges, pseudoknots, guanine quartets and the like. Aptamers are thought to specifically recognize and bind to target molecules by taking such secondary structures, and secondary structures are also considered to play an important role in deoxyribozymes or ribozymes. .
However, natural DNA aptamers, deoxyribozymes or ribozymes have very little binding ability and catalytic ability compared to antibodies or enzymes. There are two possible reasons for this.
1) Proteins such as antibodies or enzymes are composed of 20 types of amino acids, whereas DNA has only 4 types of nucleosides.
2) Proteins have functional groups that are present in large numbers in active centers such as imidazole or amino groups, whereas nucleic acids do not have such.
For this reason, in the in vitro selection method, it is considered that the use of modified DNA into which various functional substituents are introduced to enhance the binding ability and catalytic ability is effective.

For the synthesis of the modified DNA as described above, a modified nucleoside having a functional substituent introduced therein is useful. Various modified nucleosides are known, but guanine derivatives are less than other nucleobase derivatives, and their structures are limited to specific ones. For example, Japanese Patent Application Laid-Open No. 2004-262791 (Patent Document 1) describes an 8-substituted guanosine derivative having a methyl group at the 8-position of guanine. However, the method described in the publication cannot introduce a functional substituent at the 8-position of guanine.
JP 2004-262791 A

  Under such circumstances, provision of a modified nucleoside into which a functional substituent has been introduced, particularly an 8-substituted guanosine derivative into which a functional substituent has been introduced, has been demanded.

  The present inventors focused on guanine, which plays a particularly important role in various secondary structures such as guanine quartet, and designed modified nucleosides into which various hydrogen-bonding substituents were introduced, and tried to synthesize them. . Note that the position of introduction of the hydrogen bonding substituent is not directly related to DNA double strand formation, and guanine can be introduced to the DNA major group via a flexible alkyl straight chain. 8th place.

  As a result, a series of 1) bromination, 2) coupling reaction using Pd catalyst, and 3) catalytic hydrogenation of the sugar moiety under hydroxyl-unprotected conditions, starting from guanosine or 2′-deoxyguanosine, And succeeded in introducing various hydrogen bonding substituents at position 8 of guanine.

  The present inventors have already established a method for synthesizing an 8-substituted adenosine derivative having a hydrogen bonding substituent (Y. Saito et al., Tetrahedron Letters 46 (2005) 7605-7608). As shown in this document, the adenosine derivative can sufficiently proceed the reaction without protecting the hydroxyl group of the sugar moiety. However, since the guanosine derivative has a very low solubility as compared with the adenosine derivative, it is generally considered that the reaction is carried out while protecting the hydroxyl group of the sugar moiety. Contrary to such conventional technical common knowledge, the present invention has completed the present invention by allowing the hydroxyl group of the sugar moiety to proceed under unprotected conditions.

（式中、Ｒ¹は水素結合性置換基であり、Ｒ²は水素原子または水酸基であり、ｎは１〜１０の整数である。）で表される８−置換グアノシン誘導体。
［２］Ｒ¹は、−ＮＨ₂、−ＳＨ、−ＣＮ、−ＯＨ、−ＮＨ−Ｃ（＝Ｒ）ＮＨ₂（Ｒは酸素原子またはイミノ基を表す。）、−ＣＯＯＲ’（Ｒ’は水素原子または低級アルキル基を表す。）、−ＣＯＮＨ₂、−ＣＳＮＨ₂、−Ｃ（＝ＮＨ）ＮＨ₂、−ＮＨ−ＣＯＣＦ₃、−ＯＣＯＣＨ₃及び−Ｓ−Ｓ（ＣＨ₃）₃からなる群から選ばれるものである、［１］記載の８−置換グアノシン誘導体。
［３］下記式（ａ）：

（式中、Ｒ²は水素原子または水酸基である。）；
下記式（ｂ）：

（式中、Ｒ²は水素原子または水酸基であり、Ｒ³は酸素原子またはイミノ基である。）；
下記式（ｃ）：

（式中、Ｒ²は水素原子または水酸基であり、Ｒ⁴は−Ｃ（＝ＮＨ）ＮＨ₂、−ＣＯＯＲ”（Ｒ”は水素原子または低級アルキル基を表す。）、−ＣＯＮＨ₂または−ＣＳＮＨ₂である。）；あるいは
下記式（ｄ）：

（式中、Ｒ²は水素原子または水酸基であり、Ｒ⁵は−ＯＣＯＣＨ₃または−Ｓ−Ｓ（ＣＨ₃）₃である。）
で表されるものである［１］記載の８−置換グアノシン誘導体。
［４］下記式（ＩＩ）：

（式中、Ｒ⁶は水素結合性置換基を含む有機基であり、Ｒ²は水素原子または水酸基であり、ＤＭＴｒはジメトキシトリチル基であり、ｎは１〜１０の整数である。）で表される８−置換グアノシン誘導体。
［５］Ｒ¹は、−ＮＨ₂、−ＳＨ、−ＣＮ、−ＯＨ、−ＮＨ−Ｃ（＝Ｒ）ＮＨ₂（Ｒは酸素原子またはイミノ基を表す。）、−ＣＯＯＲ’（Ｒ’は水素原子または低級アルキル基を表す。）、−ＣＯＮＨ₂、−ＣＳＮＨ₂、−Ｃ（＝ＮＨ）ＮＨ₂、−ＮＨ−ＣＯＣＦ₃、−ＯＣＯＣＨ₃及び−Ｓ−Ｓ（ＣＨ₃）₃からなる群から選ばれるものである、［４］記載の８−置換グアノシン誘導体。
［６］下記式（ｅ）：

（式中、Ｒ²は水素原子または水酸基であり、ＤＭＴｒはジメトキシトリチル基である。）；
下記式（ｆ）：

（式中、Ｒ²は水素原子または水酸基であり、Ｒ³は酸素原子またはイミノ基であり、ＤＭＴｒはジメトキシトリチル基である。）；
下記式（ｇ）：

（式中、Ｒ²は水素原子または水酸基であり、Ｒ⁴は−Ｃ（＝ＮＨ）ＮＨ₂、−ＣＯＯＲ”（Ｒ”は水素原子または低級アルキル基を表す。）、−ＣＯＮＨ₂または−ＣＳＮＨ₂であり、ＤＭＴｒはジメトキシトリチル基である。）；あるいは
下記式（ｈ）：

（式中、Ｒ²は水素原子または水酸基であり、Ｒ⁵は−ＯＣＯＣＨ₃または−Ｓ−Ｓ（ＣＨ₃）₃であり、ＤＭＴｒはジメトキシトリチル基である。）
で表されるものである、［４］記載の８−置換グアノシン誘導体。
［７］下記式（ＩＩＩ）：

（式中、Ｒ²は水素原子または水酸基であり、Ｒ⁶は水素結合性置換基を含む有機基であり、ｍは０〜９である。）で表される化合物を、糖部分の水酸基を無保護条件下、接触水添させる工程を含む、［１］から［６］までの何れか記載の８−置換グアノシン誘導体の製造方法。
［８］水素結合性置換基を８位に有するグアニン誘導体を含むオリゴヌクレオチド。
［９］［４］から［６］までの何れかに記載の８−置換グアノシン誘導体を用いることを含む、［８］記載のオリゴヌクレオチドの製造方法。 That is, the present invention relates to the following 8-substituted guanosine derivatives and oligonucleotides and methods for producing them.
[1] The following formula (I):

(Wherein, R ¹ is a hydrogen-bonding substituent, R ² is a hydrogen atom or a hydroxyl group, and n is an integer of 1 to 10).
[2] R ¹ represents —NH ₂ , —SH, —CN, —OH, —NH—C (═R) NH ₂ (R represents an oxygen atom or an imino group), —COOR ′ (R ′ represents represents a hydrogen atom or a lower alkyl _{group), -. CONH 2, -CSNH} 2, -C (= NH) NH 2, -NH-COCF 3, the group consisting of -OCOCH ₃ and -S-S (CH _{3) 3} The 8-substituted guanosine derivative according to [1], which is selected from:
[3] The following formula (a):

(Wherein R ² is a hydrogen atom or a hydroxyl group);
The following formula (b):

(Wherein R ² is a hydrogen atom or a hydroxyl group, and R ³ is an oxygen atom or an imino group);
The following formula (c):

(Wherein R ² is a hydrogen atom or a hydroxyl group, R ⁴ is —C (═NH) NH ₂ , —COOR ″ (R ″ represents a hydrogen atom or a lower alkyl group), —CONH ₂ or —CSNH. ₂ ); or the following formula (d):

(In the formula, R ² is a hydrogen atom or a hydroxyl group, and R ⁵ is —OCOCH ₃ or —S—S (CH ₃ ) _3. )
The 8-substituted guanosine derivative according to [1], which is represented by:
[4] The following formula (II):

(Wherein R ⁶ is an organic group containing a hydrogen bonding substituent, R ² is a hydrogen atom or a hydroxyl group, DMTr is a dimethoxytrityl group, and n is an integer of 1 to 10). 8-substituted guanosine derivatives.
[5] R ¹ represents —NH ₂ , —SH, —CN, —OH, —NH—C (═R) NH ₂ (R represents an oxygen atom or an imino group), —COOR ′ (R ′ represents represents a hydrogen atom or a lower alkyl _{group), -. CONH 2, -CSNH} 2, -C (= NH) NH 2, -NH-COCF 3, the group consisting of -OCOCH ₃ and -S-S (CH _{3) 3} The 8-substituted guanosine derivative according to [4], which is selected from:
[6] The following formula (e):

(Wherein R ² is a hydrogen atom or a hydroxyl group, and DMTr is a dimethoxytrityl group);
Formula (f) below:

(Wherein R ² is a hydrogen atom or a hydroxyl group, R ³ is an oxygen atom or an imino group, and DMTr is a dimethoxytrityl group);
The following formula (g):

(Wherein R ² is a hydrogen atom or a hydroxyl group, R ⁴ is —C (═NH) NH ₂ , —COOR ″ (R ″ represents a hydrogen atom or a lower alkyl group), —CONH ₂ or —CSNH. ₂ and DMTr is a dimethoxytrityl group); or the following formula (h):

(Wherein R ² is a hydrogen atom or a hydroxyl group, R ⁵ is —OCOCH ₃ or —S—S (CH ₃ ) ₃ , and DMTr is a dimethoxytrityl group.)
The 8-substituted guanosine derivative according to [4], which is represented by:
[7] The following formula (III):

(Wherein R ² is a hydrogen atom or a hydroxyl group, R ⁶ is an organic group containing a hydrogen-bonding substituent, and m is 0 to 9). The method for producing an 8-substituted guanosine derivative according to any one of [1] to [6], comprising a step of contact hydrogenation under unprotected conditions.
[8] An oligonucleotide containing a guanine derivative having a hydrogen bonding substituent at the 8-position.
[9] A method for producing an oligonucleotide according to [8], comprising using the 8-substituted guanosine derivative according to any one of [4] to [6].

According to the present invention, guanosine derivatives having various hydrogen bonding substituents at the 8-position can be provided. In addition, according to the present invention, an oligonucleotide containing a guanine derivative having various hydrogen bonding substituents at the 8-position can be provided.
By introducing the guanosine derivative having a hydrogen bonding substituent of the present invention into various sequences such as guanine quartet, stabilization of their structures can be expected, aptamers having higher binding ability and catalytic ability, deoxyribozymes, And ribozymes can be obtained.

  Hereinafter, the 8-substituted guanosine derivative and oligonucleotide of the present invention and the production method thereof will be described in detail.

で表される。 A. 8-Substituted Guanosine Derivative The 8-substituted guanosine derivative of the present invention has the following formula (I):

It is represented by

  As represented by the formula (I), the 8-substituted guanosine derivative of the present invention has a hydrogen bonding substituent at the 8-position of guanine. Position 8 of guanine is not directly involved in DNA duplex formation. For this reason, when the 8-substituted guanosine derivative of the present invention is introduced into an oligonucleotide by introducing a hydrogen-bonding substituent at this position through a flexible alkyl straight chain, the DNA major group has hydrogen-bonding properties. Substituents can be released.

In the formula (I), R ¹ is a hydrogen bonding substituent. The hydrogen bonding substituent is not particularly limited as long as it is a substituent capable of forming a hydrogen bond between molecules or within a molecule. The hydrogen bonding substituent is preferably —NH ₂ , —SH, —CN, —OH, —NH—C (═R) NH ₂ (R represents an oxygen atom or an imino group), —COOR ′ ( R 'represents a hydrogen atom or a lower alkyl _{group), -. CONH 2, -CSNH} 2, -C (= NH) NH 2, -NH-COCF 3, -OCOCH 3 and -S-S (CH _{3) 3} Selected from the group consisting of In the present specification, the lower alkyl group means a linear or branched alkyl group having 1 to 6 carbon atoms. Examples of the lower alkyl group include isopropyl, n-butyl, sec-butyl, tert-butyl, pentyl, hexyl and the like.

R ² is a hydrogen atom or a hydroxyl group. When R ² is a hydrogen atom, the sugar moiety is β-D-2′-deoxyribose, and when R ² is a hydroxyl group, the sugar moiety is β-D-ribose. That is, the 8-substituted guanosine derivative of the present invention includes both 2′-deoxyguanosine derivatives and guanosine derivatives.

  n is an integer of 1-10. Preferably, n is 1-6, more preferably n is 1-4, and still more preferably n is 1 or 2.

（式中、Ｒ²は水素原子または水酸基である。）；

（式中、Ｒ²は水素原子または水酸基であり、Ｒ³は酸素原子またはイミノ基である。）；

（式中、Ｒ²は水素原子または水酸基であり、Ｒ⁴は−Ｃ（＝ＮＨ）ＮＨ₂、−ＣＯＯＲ”（Ｒ^"は水素原子または低級アルキル基を表す。）、−ＣＯＮＨ₂または−ＣＳＮＨ₂である。）；

（式中、Ｒ²は水素原子または水酸基であり、Ｒ⁵は−ＯＣＯＣＨ₃または−Ｓ−Ｓ（ＣＨ₃）₃である。） Preferred embodiments of the present invention include, for example, compounds represented by the following formulas (a) to (d).

(Wherein R ² is a hydrogen atom or a hydroxyl group);

(Wherein R ² is a hydrogen atom or a hydroxyl group, and R ³ is an oxygen atom or an imino group);

(Wherein R ² represents a hydrogen atom or a hydroxyl group, R ⁴ represents —C (═NH) NH ₂ , —COOR ″ (R ^″ represents a hydrogen atom or a lower alkyl group), —CONH ₂ or —CSNH. ₂ );

(In the formula, R ² is a hydrogen atom or a hydroxyl group, and R ⁵ is —OCOCH ₃ or —S—S (CH ₃ ) _3. )

  The above is an example, and these compounds can be used as intermediate products to derive compounds having other hydrogen bonding substituents in accordance with conventional methods. The 8-substituted guanosine derivative represented by the formula (I) of the present invention includes a compound thus obtained.

で表される化合物をも含む。以下、式（ＩＩ）で表される化合物について説明する。 The 8-substituted guanosine derivative represented by the formula (I) is itself useful as a nucleic acid pharmaceutical such as an anticancer agent, an antiviral agent, and an anti-HIV, but an 8-substituted guanosine derivative having a hydrogen bonding substituent is When introduced into the oligonucleotide, it is desirable to appropriately protect the reactive substituents such as the hydroxyl group of the sugar moiety and the amino group of the guanine moiety of the 8-substituted guanosine derivative represented by the formula (I). The 8-substituted guanosine derivative of the present invention is a compound in which such a reactive substituent is protected with a protecting group, that is, the following formula (II):

The compound represented by these is also included. Hereinafter, the compound represented by the formula (II) will be described.

In the formula (II), R ⁶ is an organic group containing a hydrogen bonding substituent. Here, the organic group containing a hydrogen bonding substituent is not particularly limited as long as it is a monovalent organic group containing a hydrogen bonding substituent. For example, the hydrogen bonding substituent itself or an organic group in which the hydrogen bonding substituent is protected with a protecting group is included. Specific examples include an organic group in which a hydrogen-bonding substituent such as an amino group is protected by a protecting group such as a trifluoroacetamide group. Since the hydrogen bonding substituent is the same as that described in formula (I), description thereof will not be repeated here.
R ² is a hydrogen atom or a hydroxyl group, and n is an integer of 1 to 10. The preferred range of n is the same range as described in formula (I).

  By using the 8-substituted guanosine derivative represented by the formula (II), an oligonucleotide containing a guanine derivative having a hydrogen bonding substituent at the 8-position can be produced by a simple method. The 8-substituted guanosine derivative represented by the formula (II) can be easily produced from the 8-substituted guanosine derivative represented by the formula (I). Details will be described in the section of the embodiment.

（式中、Ｒ²は水素原子または水酸基である。）；

（式中、Ｒ²は水素原子または水酸基であり、Ｒ³は酸素原子またはイミノ基である。）；

（式中、Ｒ²は水素原子または水酸基であり、Ｒ⁴は−Ｃ（＝ＮＨ）ＮＨ₂、−ＣＯＯＲ^"（Ｒ^"は水素原子または低級アルキル基を表す。）、−ＣＯＮＨ₂または−ＣＳＮＨ₂であり、ＤＭＴｒはジメトキシトリチル基である。）；または

（式中、Ｒ²は水素原子または水酸基であり、Ｒ⁵は−ＯＣＯＣＨ₃または−Ｓ−Ｓ（ＣＨ₃）₃である。） Preferred embodiments of the present invention include, for example, compounds represented by the following formulas (e) to (h).

(Wherein R ² is a hydrogen atom or a hydroxyl group);

(Wherein R ² is a hydrogen atom or a hydroxyl group, and R ³ is an oxygen atom or an imino group);

(Wherein R ² represents a hydrogen atom or a hydroxyl group, R ⁴ represents —C (═NH) NH ₂ , —COOR ^“ (R ^” represents a hydrogen atom or a lower alkyl group), —CONH ₂ or —CSNH. ₂ and DMTr is a dimethoxytrityl group)); or

(In the formula, R ² is a hydrogen atom or a hydroxyl group, and R ⁵ is —OCOCH ₃ or —S—S (CH ₃ ) _3. )

  The above is an example. Using these compounds as intermediate products, compounds having other hydrogen-bonding substituents can be derived according to a conventional method. The 8-substituted guanosine derivative represented by the formula (II) of the present invention includes a compound thus obtained.

  Next, a method for producing the 8-substituted guanosine derivative of the present invention will be described. Any of the 8-substituted guanosine derivatives of the present invention can be produced by a simple method using natural 2'-deoxyguanosine or guanosine as a starting material.

で表される化合物を、糖部分の水酸基を無保護条件下、接触水添させる工程を含むことを特徴とする。 The method of the present invention includes a step of catalytic hydrogenation of a substituted alkylene group introduced into guanosine without protecting the hydroxyl group of the sugar moiety. According to this method, the desired compound is obtained in a high yield and in a short time. Can be synthesized. That is, the method for producing an 8-substituted guanosine derivative of the present invention has the following formula (III):

And a step of catalytically hydrogenating the hydroxyl group of the sugar moiety under unprotected conditions.

In the formula (III), R ² is a hydrogen atom or a hydroxyl group, and R ⁶ is an organic group containing a hydrogen bonding substituent. In addition, the organic group containing a hydrogen bondable substituent is the same as what was demonstrated in Formula (II), and its preferable illustration is also as above-mentioned. m is an integer of 0 to 9, preferably m is 0 to 5, more preferably m is 0 to 3, and more preferably m is 0 or 1.

  The compound represented by the formula (III) can be synthesized according to a conventional method using, for example, natural 2'-deoxyguanosine or guanosine as a starting material. For example, the 8'-position of guanine in 2'-deoxyguanosine or guanosine can be synthesized by 1) bromination, and 2) a suitable acetylene derivative by a coupling reaction using a Pd catalyst. For details, schemes 1 to 4 in Examples can be referred to.

（式中のＲ²、Ｒ⁶は前記のとおりであり、ｎは１〜１０である。）で表される化合物を得ることができる。なお、好ましくは、ｎは１〜６、より好ましくは、ｎは１〜４、さらに好ましくは、ｎは１または２である。 According to the method of the present invention, by catalytic hydrogenation of the compound represented by the formula (III), the following formula (IV):

(Wherein R ² and R ⁶ are as described above, and n is 1 to 10). In addition, Preferably, n is 1-6, More preferably, n is 1-4, More preferably, n is 1 or 2.

The above reaction is preferably performed in the presence of a palladium catalyst. For example, palladium supported on carbon such as activated carbon, that is, commercially available as so-called palladium carbon (Pd / C) can be used. The reaction temperature is, for example, 60 ° C to 0 ° C, preferably 40 ° C to 10 ° C. The amount of the palladium catalyst to be used is preferably 100 mol% to 1 mol% with respect to the compound represented by the formula (III).
The reaction can also be performed in the presence of a platinum oxide catalyst. In this case, the reaction temperature is, for example, 100 ° C to 4 ° C, preferably 60 ° C to 10 ° C. The amount of the platinum oxide catalyst used is preferably 100 mol% to 1 mol% with respect to the compound represented by the formula (III).
The reaction solvent is not particularly limited as long as it is inert to the compound represented by the formula (III) or the formula (IV), the catalyst to be used, and the like. For example, when a palladium catalyst is used, alcohol solvents such as methanol, dichloromethane, chloroform and the like can be preferably used. In the case of using a platinum oxide catalyst, acetic acid or the like can be used.
In addition, the kind of catalyst used for this reaction, its usage-amount, reaction temperature, and a reaction solvent can be suitably determined depending on various conditions, such as a starting material.
During the reaction, it is preferable to vigorously stir the reaction solution regardless of which catalyst is used.

  According to the method of the present invention, the target compound, that is, the compound represented by the formula (IV) is obtained efficiently in a short time compared with the case where the reaction is carried out by protecting the hydroxyl group of the sugar moiety with a protecting group. be able to.

（式中のＲ²、Ｒ⁶、ｎおよびＤＭＴｒＯは、前記のとおりである。）で表される化合物を得ることができる。具体的には、実施例に示したスキーム１〜４を参照することができる。 The compound represented by formula (IV) is protected by the following formula (II) by protecting the hydroxyl group of the sugar moiety and the amino group of the guanine moiety with an appropriate protecting group according to a conventional method.

(Wherein R ² , R ⁶ , n and DMTrO are as described above) can be obtained. Specifically, schemes 1 to 4 shown in Examples can be referred to.

B. Oligonucleotides containing a guanine derivative having a hydrogen bonding substituent at position 8 Next, the oligonucleotide of the present invention will be described.
The oligonucleotide of the present invention is characterized by including a guanine derivative having a hydrogen bonding substituent at the 8-position. The introduction position of this hydrogen bonding substituent is not directly involved in DNA double strand formation. For this reason, by introducing a hydrogen bonding substituent through a flexible alkyl straight chain, the hydrogen bonding substituent can interact with other hydrogen bonding substituents within or between molecules. . By introducing such oligonucleotides of the present invention into various sequences such as guanine quartet, stabilization of their structures can be expected, and aptamers, deoxyribozymes or ribozymes having higher binding ability and catalytic ability can be obtained. Can do.

  The oligonucleotide of the present invention can be produced by using an 8-substituted guanosine derivative represented by the above formula (II), preferably an 8-substituted guanosine derivative represented by the above formulas (e) to (h). it can. For example, a solid phase synthesis method of a DNA oligomer using a commercially available DNA synthesizer can be used (for example, the literature FC Richardson et al., Nucleic Acid Research 20 (1992) 1763-1768 Can be referred). The operation procedure and the like can be performed according to the protocol attached to each DNA synthesizer.

  Hereinafter, the 8-substituted guanosine derivative and oligonucleotide of the present invention will be described more specifically with reference to examples. In addition, an Example is an example and the range of this invention is not limited to these Examples.

Example 1
The 8-substituted guanosine derivatives of the present invention (compounds (4) and (7)) and oligonucleotides were prepared according to the following scheme 1 using 2′-deoxyguanosine as a starting material.

1) Production of Compound (2) 2′-Deoxyguanosine (1) (5.681 g, 0.021 mol) was suspended in 400 ml of distilled water, and N-bromosuccinimide (4.17 g, 0.023 mol) was added. It was. This solution was stirred at room temperature for 30 minutes, and the precipitated solid was collected by suction filtration and washed with distilled water and acetone to obtain a pale purple solid (5.57 mg, 76%).
The spectrum data of the obtained compound (2) are as follows.
¹ H NMR (CD ₃ OD, 400 MHz) δ 2.10 (ddd, 1H, H-2 ′, J = 3.0 Hz, 6.6 Hz, 13.2 Hz), δ 3.16 (ddd, 1H, H− 2 ′, J = 6.4 Hz, 7.8 Hz, 13.6 Hz), δ 3.50 (dd, 1H, H-5 ′, J = 6.0 Hz, 12 Hz), δ 3.62 (dd, 1H, H-5 ′, J = 5.6 Hz, 11.2 Hz), δ 3.80 (ddd, 1H, H-3 ′, J = 3.2 Hz, 5.6 Hz, 11.2 Hz), δ 4.40 ( ddd, 1H, H-4 ′, J = 3.2 Hz, 6.8 Hz, 13.2 Hz), δ 6.16 (dd, 1H, H−1 ′, J = 6.9 Hz, 7.7 Hz), δ 10.81 (s, 1H, H-9)

2) Production of Compound (3) Compound (2) (300 mg, 0.867 mmol) obtained in the above step 1) was dissolved in 30 ml of anhydrous N, N-dimethylformamide, and N-propargyltrifluoro was added under an argon atmosphere. Acetamide (390 mg, 2.581 mmol) was added. Furthermore, copper (I) iodide (33 mg, 0.173 mmol) was added to this solution.
), Tetrakistriphenylphosphine palladium (0) (99 mg, 0.086 mmol), and triethylamine (148 μl, 1.463 mmol) were added. The solution was stirred at 55 ° C. for 2 hours. After confirming the disappearance of the raw materials by thin layer chromatography (TLC), the reaction solvent was distilled off under reduced pressure, and the residue was purified by column chromatography (silica gel, solute solvent chloroform / methanol = 7/1) to obtain the target compound (3 ) As a brown solid (331 mg, 92%).
The spectrum data of the obtained compound (3) are as follows.
¹ H NMR (CD ₃ OD, 400 MHz) δ 2.09 (ddd, 1H, H-2 ′, J = 2 Hz, 6.4 Hz, 13.2 Hz), δ 2.91 (ddd, 1H, H-2 ′) , J = 6 Hz, 8.4 Hz, 14.6 Hz), δ 3.59 (dd, 1H, H-5 ′, J = 4.0 Hz, 12.0 Hz), δ 3.70 (dd, 1H, H− 5 ′, J = 2.8 Hz, 12.0 Hz), δ 3.86 (m, 1H, H-3 ′), δ 4.25 (s, 2H, TFAHN—CH ₂ —), δ 4.44 ( m, 1H, H-4 ′), δ 6.26 (dd, 1H, H-1 ′, J = 6.8 Hz, 8.0 Hz)

3) Production of Compound (4) Compound (3) (300 mg, 0.721 mmol) obtained in the above step 2) was dissolved in 15 ml of absolute ethanol. After adding 50 mg of palladium carbon (10%) to this solution and replacing with hydrogen, the mixture was stirred at room temperature for 2 hours, the palladium carbon was removed by filtration, dissolved again in 15 ml of solvent methanol, and palladium carbon (10%) was added. After adding 50 mg and replacing with hydrogen, the mixture was stirred at room temperature for 14 hours. After confirming the disappearance of the raw materials by thin layer chromatography (TLC), the reaction solvent was distilled off under reduced pressure, and the residue was purified by column chromatography (silica gel, solute solvent chloroform / methanol = 7/1) to give a yellow oil (245 mg). , 81%).
The spectrum data of the obtained compound (4) are as follows.
¹ H NMR (CD ₃ OD, 400 MHz) δ 1.92 (q, 2H, —CH ₂ —, J = 7.2 Hz), δ 2.12 (ddd, 1H, H-2 ′, J = 2.2 Hz) , 6.2Hz, 13.2Hz), δ 2.78 (t, 2H, - CH 2 -CH 2 -), δ 2.99 (ddd, 1H, H-2 ', J = 6Hz, 8.4Hz, 14.6 Hz), δ 3.28 (t, 2H, TFANH—CH ₂ —), δ 3.65 (dd, 1H, H-5 ′, J = 4.0 Hz, 12.0 Hz), δ 3.75 (Dd, 1H, H-5 ′, J = 3.2 Hz, 12.0 Hz), δ 3.92 (dd, 1H, H-3 ′, J = 32.Hz, 6.0 Hz), δ 4.54 (M, 1H, H-4 ′), δ 6.14 (dd, 1H, H-1 ′, J = 6.2 Hz, 8.6 Hz)

4) Production of Compound (5) Compound (4) (178 mg, 0.423 mmol) obtained in the above step 3) was dissolved in 10 ml of anhydrous N, N-dimethylformamide under an argon atmosphere, and N, N′-dimethyl was dissolved. Formamide diethyl acetal (1 ml, 5.835 mmol) was added. The solution was stirred at 50 ° C. for 2 hours and thin layer chromatography (TLC)
After confirming the disappearance of the raw materials, the reaction solvent was distilled off under reduced pressure. The residue was purified by column chromatography (silica gel, solute solvent chloroform / methanol = 7/1) to obtain the target compound (5) as a pale yellow solid (199 mg, 99%).
The spectrum data of the obtained compound (5) are as follows.
¹ H NMR (CD ₃ OD, 400 MHz) δ 1.94 (q, 2H, —CH ₂ —, J = 7.2 Hz), δ 2.16 (ddd, 1H, H-2 ′, J = 2.8 Hz) , 6.4Hz, 13.6Hz), δ 280 (t, 2H, - CH 2 -CH 2 -), δ 2.97 (s, 3H, N (CH 3)), δ 3.14 (m, 4H , N (CH ₃ ), H-2 ′), δ 3.27 (t, 2H, TFANH—CH ₂ —), δ 3.62 (dd, 1H, H-5 ′, J = 4.0 Hz, 12 .0Hz), δ 3.72 (dd, 1H, H-5 ′, J = 3.4 Hz, 12.2 Hz), δ 3.89 (dd, 1H, H-3 ′, J = 3.6 Hz, 6) .8 Hz), δ 4.54 (m, 1H, H-4 ′), δ 6.38 (dd, 1H, H−1 ′, J = 6.4 Hz, 8.0 Hz), δ 8.38 (s) , 1H, N = CH-N)

5) Production of Compound (6) Compound (5) (140 mg, 0.294 mmol) obtained in Step 4) was dissolved in 10 ml of anhydrous pyridine under an argon atmosphere, and 4,4′-dimethoxytrityl chloride (120 mg, 120 mg, 0.354 mmol), N, N-dimethylaminopyridine (7.2 mg, 0.059 mmol) was added. This solution was stirred at room temperature for 1 hour. After confirming the disappearance of the raw material by thin layer chromatography (TLC), the reaction solvent was distilled off under reduced pressure. The residue was purified by column chromatography (silica gel, elution solvent chloroform / methanol / triethylamine = 89/10/1) to obtain the target compound (6) as a pale yellow solid (220 mg, 96%).
The spectrum data of the obtained compound (6) are as follows.
¹ H NMR (CD ₃ OD, 400 MHz) δ 1.85 (m, 2H, —CH ₂ —), δ 2.12 (ddd, 1H, H-2 ′, J = 2 Hz, 6 Hz, 8.0 Hz, 13 .6Hz), δ 2.77 (m, 9H, - CH 2 -CH 2 -, N (CH 3, H-2 '), δ 3.22 (m, 3H, H-5', TFANH-CH 2 −), Δ 3.49 (d, 6H, —O—CH ₃ , J = 2.8 Hz), δ 3.82 (m, 1H, H-3 ′), δ 4.58 (m, 1H, H) -4 ′), δ 6.06 (dd, 1H, H-1 ′, J = 5.2 Hz, 7.6 Hz), δ 6.40-7.09 (m, 13H, Ar—H), δ 8 .14 (s, 1H, N = CH-N)

6) Preparation of Compound (7) Compound (6) (46 mg, 0.059 mmol) obtained in the above step 5) was dissolved in 460 μl of anhydrous dichloromethane under an argon atmosphere, and 1H-tetrazole anhydrous acetonitrile solution (0.45 M, 196 μl, 0.088 mmol), 2-cyanoethyl-N, N, N ′, N′-tetraisopropyl phosphorodiamidite (28 μl, 0.089 mmol) was added. The solution was stirred at room temperature for 2 hours. After confirming the disappearance of the raw materials by thin layer chromatography (TLC), the reaction solution was transferred to a separatory funnel, washed with saturated sodium bicarbonate water and distilled water, and the organic layer was washed with sodium sulfate. After drying, the reaction solvent was distilled off under reduced pressure. The residue was dissolved in 1 ml of anhydrous acetonitrile and filtered through Cosmonis filter S (solvent system, manufactured by Nacalai Tesque, Inc.). The filtrate was distilled off under reduced pressure to obtain the target compound (7) as a crude product. The crude product of compound (7) was used as it was for DNA synthesis.

7) Step of obtaining oligonucleotide from compound (7) The target sequence (3400 DNA / RNA synthesizer, Applied Biosystems) using compound (7) obtained in the above step 6) using the target sequence ( 5′-CGCAATXTAACGC-3 ′ and 5′-CGCAACXCAACGC-3 ′) were synthesized. After completion of the synthesis, the solution cut out from the solid support was transferred to an Eppendorf tube and heated at 37 ° C. for 18 hours for deprotection. The obtained oligonucleotide chain was purified by high performance liquid chromatography (PU-2080-puls, JASCO). After purification, the solvent was distilled off under reduced pressure by lyophilization to obtain an oligonucleotide chain of the target sequence (5′-CGCAATXTAACGC-3 ′ and 5′-CGCAACXCAACGC-3 ′). Moreover, the target object was confirmed using MALDI-TOF Mass (AXIMA-LNR, SHIMADZU).
5′-CGCAATXTAACGC-3 ′ [M + H] +: cacc. = 41999.9744, found = 4200.12
5′-CGCAACXCAACGC-3 ′ [M + H] +: cacc. = 42299.9980, found = 4230.28

  The above is the case where 2′-deoxyguanosine is used as a starting material. However, even when guanosine is used as a starting material, the 8-replaced guanosine of the present invention is prepared using the same reaction reagent and reaction conditions. Derivatives as well as oligonucleotides can be produced. Moreover, the compound corresponding to the 8-substituted guanosine derivative represented by the above formula (I) can also be obtained as an intermediate product by deprotecting the compound (4) according to a conventional method.

  Next, Examples 2 to 4 show 8-substituted guanosine derivatives having hydrogen-bonding substituents other than those shown in Example 1 and methods for producing oligonucleotides using the same. In all of Examples 2 to 4, a derivative of 2′-deoxyguanosine is used as a starting material. However, when a guanosine derivative is used as a starting material, the target compound is obtained using the same reaction reagent and reaction conditions. Can be manufactured.

Example 2
The 8-substituted guanosine derivative represented by the formula (b) or (f) (corresponding to the compound (9) and the compound (12) of Scheme 2 respectively) and the oligonucleotide using the same are as follows. It can be prepared according to Scheme 2.

1) Production of Compound (8) Compound (4) obtained in the above step is dissolved in an excess amount of 28% aqueous ammonia. This solution is stirred at room temperature for 1 day, and after confirming the disappearance of the raw material by thin layer chromatography (TLC), the reaction solvent is distilled off under reduced pressure. This is transferred to a separatory funnel and washed with chloroform, and then the aqueous layer is distilled off under reduced pressure to obtain the desired compound (8).

2) Production of Compound (9a) Compound (8) obtained in the above step is dissolved in distilled water, and potassium cyanate is added. The solution was stirred at 55 ° C. for 1 day, and disappearance of the starting material was confirmed by thin layer chromatography (TLC). Then, the reaction solvent was distilled off under reduced pressure, and the residue was purified by HW-40C to obtain the desired compound (9a). Obtainable.

3) Production of compound (9b) In an argon atmosphere, the compound (8) obtained in the above step is dissolved in distilled water, and potassium carbonate and aminoiminomethanesulfonic acid are added. This solution was stirred at room temperature for 1 day. After confirming the disappearance of the raw materials by reverse layer thin layer chromatography (TLC), the reaction solvent was distilled off under reduced pressure, and the residue was purified by HW-40C to obtain the desired compound (9b). Can be obtained.

4) Production of Compound (10) In an argon atmosphere, the compound (9) obtained in the above step is dissolved in anhydrous N, N-dimethylformamide, and 1 ml of N, N-dimethylformamide diethyl acetal is added. This solution is stirred at 55 ° C. for 3 hours. After confirming the disappearance of the raw material by thin layer chromatography (TLC), the reaction solvent is distilled off under reduced pressure. The residue can be purified by column chromatography (silica gel, solute solvent chloroform / methanol = 7/1) to obtain the target compound (10).

5) Production of Compound (11) In an argon atmosphere, the compound (10) obtained in the above step is dissolved in anhydrous pyridine, and 4,4′-dimethoxytrityl chloride and N, N-dimethylaminopyridine are added. This solution is stirred at room temperature for 8 hours, and after confirming disappearance of the raw material by thin layer chromatography (TLC), the reaction solvent is distilled off under reduced pressure. The residue can be purified by column chromatography (silica gel, solute solvent chloroform / methanol / triethylamine = 89/10/1) to obtain the target compound (11).

6) Production of Compound (12) Compound (11) obtained in the above step was dissolved in anhydrous dichloromethane under an argon atmosphere, and 1H-tetrazole anhydrous acetonitrile solution, 2-cyanoethyl-N, N, N ′, N′— Add tetraisopropyl phosphorodiamidite. This solution is stirred at room temperature for 2 hours, and after disappearance of raw materials is confirmed by thin layer chromatography (TLC), it is washed with saturated sodium bicarbonate water and distilled water. After drying the organic phase with anhydrous sodium sulfate, the reaction solvent is distilled off under reduced pressure. The residue can be dissolved in 1 ml of anhydrous acetonitrile, filtered through Cosmonis filter S (solvent system, manufactured by Nacalai Tesque), and the filtrate can be distilled off under reduced pressure to obtain the desired compound (12) as a crude product. it can. The crude product of compound (12) can be used as it is for DNA synthesis.

  The step of obtaining the oligonucleotide from the compound (12) can be performed in the same manner as the step of obtaining the oligonucleotide from the compound (7) of Example 1. It can carry out similarly in Example 3 and 4.

Example 3
The 8-substituted guanosine derivative represented by the formula (c) or (g) (corresponding to the compound (15) and the compound (18) in Scheme 3 respectively) and the oligonucleotide using the same are as follows. It can be prepared according to Scheme 3.

1) Production of Compound (13) 8-Bromo 2′-deoxyguanosine (2) is dissolved in DMF, 2-Propynenitrile, palladium tetrakistriphenylphosphine, copper iodide and triethylamine are added and stirred overnight at room temperature. The reaction solvent is concentrated under reduced pressure, and the residue is purified by silica gel column chromatography to give compound (13).

2) Production of Compound (14a) The compound (13) obtained in the previous step is dissolved in ethanol saturated with hydrogen chloride gas and stirred at 0 ° C. for 20 hours. Thereafter, the reaction solution is concentrated, ethanol in which ammonia gas is dissolved is added to the residue, and the mixture is stirred at room temperature for 20 hours. After concentration of the reaction solvent, the residue can be purified by preparative TLC to obtain compound (14a).

3) Production of Compound (14b) Compound (13) obtained in the previous step is dissolved in ethanol saturated with hydrogen chloride gas and stirred at 0 ° C. for 2 hours. The reaction solution is concentrated, water is added to the residue, and the mixture is stirred at 0 ° C. for 1 hour. Thereafter, the reaction solution is concentrated, and the residue is purified by preparative reverse phase TLC to obtain the compound (14b).

4) Production of compound (14c) Compound (14b) obtained in the previous step is dissolved in methanol in a sealed tube, and liquid ammonia is added thereto, followed by stirring at room temperature for 14 hours. The reaction solution is concentrated, and the residue can be purified by preparative reverse phase TLC to give compound (14c).

5) Production of Compound (14d) The compound (13) obtained in the previous step is dissolved in anhydrous pyridine, and triethylamine is added to saturate the hydrogen sulfide gas at 0 ° C. Then plug and stir at room temperature for 14 hours. After concentrating the reaction solvent, the residue can be purified by preparative TLC to give compound (14d).

6) Production of Compound (15) The compounds (14a to d) obtained in the above steps 2) to 5) are dissolved in absolute ethanol. After adding palladium carbon (10%) to this solution and replacing with hydrogen, the mixture was stirred at room temperature for 2 hours, filtered to remove palladium carbon, dissolved again in solvent methanol, palladium carbon (10%) was added, After replacing with hydrogen, the mixture is stirred at room temperature for 14 hours. After confirming the disappearance of the raw materials by thin layer chromatography (TLC), the reaction solvent is distilled off under reduced pressure, and the residue is purified by column chromatography (silica gel, solute solvent chloroform / methanol) to obtain compound (15).

7) Production of Compound (16) Compound (15) obtained in the above step 6) is dissolved in anhydrous N, N-dimethylformamide under an argon atmosphere, and N, N′-dimethylformamide diethyl acetal is added. This solution is stirred at 50 ° C. for 2 hours. After confirming disappearance of the raw material by thin layer chromatography (TLC), the reaction solvent is distilled off under reduced pressure. The residue can be purified by column chromatography (silica gel, solute solvent chloroform / methanol) to obtain the target compound (16).

8) Production of Compound (17) Compound (16) obtained in the above step 7) is dissolved in anhydrous pyridine under an argon atmosphere, and 4,4′-dimethoxytrityl chloride, N, N-dimethylaminopyridine is added. This solution is stirred at room temperature for 1 hour. After confirming disappearance of the raw material by thin layer chromatography (TLC), the reaction solvent is distilled off under reduced pressure. The residue can be purified by column chromatography (silica gel, elution solvent chloroform / methanol / triethylamine) to obtain the desired compound (17).

9) Preparation of Compound (18) Compound (17) obtained in the above step 8) was dissolved in anhydrous dichloromethane under an argon atmosphere, and 1H-tetrazole anhydrous acetonitrile solution (0.45M), 2-cyanoethyl-N, N, Add N ', N'-tetraisopropyl phosphorodiamidite. The solution was stirred at room temperature for 2 hours. After confirming the disappearance of the raw materials by thin layer chromatography (TLC), the reaction solution was transferred to a separatory funnel, washed with saturated sodium bicarbonate water and distilled water, and the organic layer was washed with sodium sulfate. After drying, the reaction solvent is distilled off under reduced pressure. The residue is dissolved in 1 ml of anhydrous acetonitrile and filtered through a Cosmonis filter S (solvent system, manufactured by Nacalai Tesque). The filtrate can be distilled off under reduced pressure to obtain the target compound (18) as a crude product. The crude product of compound (18) can be used as it is for DNA synthesis.

Example 4
The 8-substituted guanosine derivative represented by the formula (d) or (h) (corresponding to the compound (20) and the compound (23) in Scheme 4 respectively) and the oligonucleotide using the same are as follows. It can be produced according to scheme 4.

1) Production of Compound (19) 8-Bromo 2′-deoxyguanosine (2) is dissolved in DMF, and palladium tetrakistriphenylphosphine, copper iodide, triethylamine, propargyl acetate (19a) or tert-butyl propargyl disulfide (19b) is dissolved. ) And stirred overnight at room temperature. The reaction solvent is concentrated under reduced pressure, and the residue is purified by silica gel column chromatography to give compound (13).

2) Production of Compound (20) The compound (19a or 19b) obtained in the above step 1) is dissolved in absolute ethanol. After adding palladium carbon (10%) to this solution and replacing with hydrogen, the mixture was stirred at room temperature for 2 hours, filtered to remove palladium carbon, dissolved again in solvent methanol, palladium carbon (10%) was added, After replacing with hydrogen, the mixture is stirred at room temperature for 14 hours. After confirming the disappearance of the raw materials by thin layer chromatography (TLC), the reaction solvent is distilled off under reduced pressure, and the residue is purified by column chromatography (silica gel, solute solvent chloroform / methanol) to obtain compound (20).

3) Production of Compound (21) Compound (20) obtained in the above step 2) is dissolved in anhydrous N, N-dimethylformamide under an argon atmosphere, and N, N′-dimethylformamide diethyl acetal is added. This solution is stirred at 50 ° C. for 2 hours. After confirming disappearance of the raw material by thin layer chromatography (TLC), the reaction solvent is distilled off under reduced pressure. The residue can be purified by column chromatography (silica gel, solute solvent chloroform / methanol) to obtain the desired compound (21).

4) Production of Compound (22) In an argon atmosphere, the compound (21) obtained in Step 3) is dissolved in anhydrous pyridine, and 4,4′-dimethoxytrityl chloride and N, N-dimethylaminopyridine are added. This solution is stirred at room temperature for 1 hour. After confirming disappearance of the raw material by thin layer chromatography (TLC), the reaction solvent is distilled off under reduced pressure. The residue can be purified by column chromatography (silica gel, elution solvent chloroform / methanol / triethylamine) to obtain the target compound (22).

5) Preparation of compound (23) Under argon atmosphere, compound (22) obtained in the above step 4) was dissolved in anhydrous dichloromethane, and 1H-tetrazole anhydrous acetonitrile solution (0.45M), 2-cyanoethyl-N, N, Add N ', N'-tetraisopropyl phosphorodiamidite. The solution was stirred at room temperature for 2 hours. After confirming the disappearance of the raw materials by thin layer chromatography (TLC), the reaction solution was transferred to a separatory funnel, washed with saturated sodium bicarbonate water and distilled water, and the organic layer was washed with sodium sulfate. After drying, the reaction solvent is distilled off under reduced pressure. The residue is dissolved in 1 ml of anhydrous acetonitrile and filtered through a Cosmonis filter S (solvent system, manufactured by Nacalai Tesque). The filtrate can be distilled off under reduced pressure to obtain the target compound (23) as a crude product. The crude product of compound (23) can be used as it is for DNA synthesis.

  The 8-substituted guanosine derivatives and oligonucleotides of the present invention may be widely used as nucleic acid drugs such as anticancer agents, antiviral agents, and anti-HIVs, and as reagents or tools for gene-related industries.

Claims (9)

The following formula (I):

(Wherein, R ¹ is a hydrogen-bonding substituent, R ² is a hydrogen atom or a hydroxyl group, and n is an integer of 1 to 10). R ¹ is —NH ₂ , —SH, —CN, —OH, —NH—C (═R) NH ₂ (R represents an oxygen atom or an imino group), —COOR ′ (R ′ is a hydrogen atom or Represents a lower alkyl group.), —CONH ₂ , —CSNH ₂ , —C (═NH) NH ₂ , —NH—COCF ₃ , —OCOCH ₃ and —S—S (CH ₃ ) _3. The 8-substituted guanosine derivative according to claim 1, wherein The following formula (a):

(Wherein R ² is a hydrogen atom or a hydroxyl group);
The following formula (b):

(Wherein R ² is a hydrogen atom or a hydroxyl group, and R ³ is an oxygen atom or an imino group);
The following formula (c):

(Wherein R ² is a hydrogen atom or a hydroxyl group, R ⁴ is —C (═NH) NH ₂ , —COOR ″ (R ″ represents a hydrogen atom or a lower alkyl group), —CONH ₂ or —CSNH. ₂ ); or the following formula (d):

(In the formula, R ² is a hydrogen atom or a hydroxyl group, and R ⁵ is —OCOCH ₃ or —S—S (CH ₃ ) _3. )
The 8-substituted guanosine derivative according to claim 1, which is represented by: Formula (II) below:

(Wherein R ⁶ is an organic group containing a hydrogen bonding substituent, R ² is a hydrogen atom or a hydroxyl group, DMTr is a dimethoxytrityl group, and n is an integer of 1 to 10). 8-substituted guanosine derivatives. R ¹ is —NH ₂ , —SH, —CN, —OH, —NH—C (═R) NH ₂ (R represents an oxygen atom or an imino group), —COOR ′ (R ′ is a hydrogen atom or Represents a lower alkyl group.), —CONH ₂ , —CSNH ₂ , —C (═NH) NH ₂ , —NH—COCF ₃ , —OCOCH ₃ and —S—S (CH ₃ ) _3. The 8-substituted guanosine derivative according to claim 4, wherein The following formula (e):

(Wherein R ² is a hydrogen atom or a hydroxyl group, and DMTr is a dimethoxytrityl group);
Formula (f) below:

(Wherein R ² is a hydrogen atom or a hydroxyl group, R ³ is an oxygen atom or an imino group, and DMTr is a dimethoxytrityl group);
The following formula (g):

(Wherein R ² is a hydrogen atom or a hydroxyl group, R ⁴ is —C (═NH) NH ₂ , —COOR ″ (R ″ represents a hydrogen atom or a lower alkyl group), —CONH ₂ or —CSNH. ₂ and DMTr is a dimethoxytrityl group); or the following formula (h):

(Wherein R ² is a hydrogen atom or a hydroxyl group, R ⁵ is —OCOCH ₃ or —S—S (CH ₃ ) ₃ , and DMTr is a dimethoxytrityl group.)
The 8-substituted guanosine derivative | guide_body of Claim 4 which is represented by these. Formula (III) below:

(Wherein R ² is a hydrogen atom or a hydroxyl group, R ⁶ is an organic group containing a hydrogen-bonding substituent, and m is 0 to 9). The method for producing an 8-substituted guanosine derivative according to any one of claims 1 to 6, comprising a step of contact hydrogenation under unprotected conditions.   An oligonucleotide comprising a guanine derivative having a hydrogen bonding substituent at the 8-position.   The method for producing an oligonucleotide according to claim 8, comprising using the 8-substituted guanosine derivative according to any one of claims 4 to 6.