1-substituted-4-nitroimidazole compound and process for producing the same

A method for preparing a 4-nitroimidazole compound represented by the general formula (2a),

• [wherein XA is a halogen atom], which is characterized by reducing a 4-nitroimidazole compound represented by the general formula (3),
• [wherein RA′ is a lower alkoxy group-substituted lower alkyl group, a phenyl-lower alkoxy group-substituted lower alkyl group, a cyano group-substituted lower alkyl group, or a phenyl-lower alkyl group which may have a lower alkoxy group as the substituent in the phenyl ring;
• XA and X1 are each a halogen atom], and removing the RA′ group from the obtained 1-substituted-4-nitroimidazole compound represented by the general formula (1a),
• [wherein RA′ and XA are the same as defined above].

A method for preparing a 1-substituted-4-nitroimidazole compound represented by the general formula (10),

• [wherein RA is a group of the formula
• wherein RB is a hydrogen atom or a lower alkyl group;
• and X is a halogen atom or a group of the formula —S (O)n-R1;
• n is 0 or an integer of 1 or 2;
• R1 is a phenyl group which may have 1 to 3 substituents, selected from the group consisting of a nitro group, a halogen atom and a lower alkyl group, in the phenyl ring], characterized by reacting a 4-nitroimidazole compound represented by the general formula (2),
• [wherein X is the same as defined above], with a glycidyl benzenesulfonate represented by the general formula (11),
• [wherein RA is the same as defined above;
• and RC is a group of the formula,
• wherein RD is a nitro group;
• RE is a halogen atom or a lower alkyl group;
• and a is 0 or an integer of 1 or 2;
• provided that when a is 2, then two of RE may be the same or different].

A method for preparing a 4-nitroimidazole compound represented by the general formula (2b) or (2c),

• [wherein R1 is a phenyl group which may have 1 to 3 substituents, selected from the group consisting of a nitro group, a halogen atom and a lower alkyl group, in the phenyl ring;
• and n is 0 or an integer of 1 or 2], which is characterized by removing RA′ group from the 1-substituted-4-nitroimidazole compound represented by the general formula (25) or (25a),
• [wherein n and R1 are the same as defined above;
• and RA′ is a lower alkoxy group-substituted lower alkyl group, a phenyl-lower alkoxy group-substituted lower alkyl group, a cyano group-substituted lower alkyl group, a phenyl-lower alkyl group which may have a lower alkoxy group as the substituent in the phenyl ring].

A method for preparing a 4-nitroimidazole compound represented by the general formula (25a), (2c) or (10d),

• [wherein R1 is a phenyl group which may have 1 to 3 substituents, selected from the group consisting of a nitro group, a halogen atom and a lower alkyl group, in the phenyl ring;
• R is a hydrogen atom, a lower alkoxy group-substituted lower alkyl group, a phenyl-lower alkoxy group-substituted lower alkyl group, a cyano group-substituted lower alkyl group, a phenyl-lower alkyl group which may have a lower alkoxy groups as the substituents in the phenyl ring, or a group of the formula —CH2RA;
• RA is a group of the following formula,
• wherein RB is a hydrogen atom or a lower alkyl group;
• and n1 is 1 or 2], which is characterized by oxidizing a 4-nitroimidazole compound represented by the general formula (25), (2b) or (10c),
• [wherein R1 and R are the same as defined above].

A method for preparing 1-substituted-4-nitroimidazole compound represented by the general formula (10c),

• [wherein R1 is a phenyl group which may have 1 to 3 substituents, selected from the group consisting of a nitro group, a halogen atom and a lower alkyl group, in the phenyl ring;
• and RA is a group of the formula,
• wherein R3 is a hydrogen atom or a lower alkyl group], which is characterized by nitrating a 1-substituted imidazole compound represented by the general formula (27),
• [wherein R1 and RA are the same as defined above].

A 4-nitroimidazole derivative represented by the general formula (41),

• [wherein XB is a bromine atom or a group of the formula —S(O)nR1;
• R1 is a phenyl group which may have 1 to 3 substituents, selected from the group consisting of a nitro group, a halogen atom and a lower alkyl group, in the phenyl ring;
• n is 0 or an integer of 1 or 2;
• and RJ is a group of the formula,
• (wherein RK and RL are each a tetrahydropyranyl group, a tri(lower alkyl)silyl group, a lower alkanoyl group, a phenyl-lower alkyl group which may have a lower alkoxy group as the substituent in the phenyl ring or a hydrogen atom)] or a salt thereof.