Provided is a preparation method for brivaracetam. The method has a synthetic route as shown below. The preparation method for the brivaracetam is simple, economical, environmentally friendly and suitable for industrialization:

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The present invention generally relates to novel synthetic methods, systems, kits, salts, and precursors useful in medical imaging. In some embodiments, the present invention provides compositions comprising an imaging agent precursor, which may be formed using the synthetic methods described herein. An imaging agent may be converted to an imaging agent using the methods described herein. In some cases, the imaging agent is enriched in .sup.18F. In some cases, an imaging agent including salt forms (e.g., ascorbate salt) may be used to image an area of interest in a subject, including, but not limited to, the heart, cardiovascular system, cardiac vessels, brain, and other organs.

The present invention generally relates to novel synthetic methods, systems, kits, salts, and precursors useful in medical imaging. In some embodiments, the present invention provides compositions comprising an imaging agent precursor, which may be formed using the synthetic methods described herein. An imaging agent may be converted to an imaging agent using the methods described herein. In some cases, the imaging agent is enriched in .sup.18F. In some cases, an imaging agent including salt forms (e.g., ascorbate salt) may be used to image an area of interest in a subject, including, but not limited to, the heart, cardiovascular system, cardiac vessels, brain, and other organs.

The present invention generally relates to novel synthetic methods, systems, kits, salts, and precursors useful in medical imaging. In some embodiments, the present invention provides compositions comprising an imaging agent precursor, which may be formed using the synthetic methods described herein. An imaging agent may be converted to an imaging agent using the methods described herein. In some cases, the imaging agent is enriched in .sup.18F. In some cases, an imaging agent including salt forms (e.g., ascorbate salt) may be used to image an area of interest in a subject, including, but not limited to, the heart, cardiovascular system, cardiac vessels, brain, and other organs.

The present invention generally relates to novel synthetic methods, systems, kits, salts, and precursors useful in medical imaging. In some embodiments, the present invention provides compositions comprising an imaging agent precursor, which may be formed using the synthetic methods described herein. An imaging agent may be converted to an imaging agent using the methods described herein. In some cases, the imaging agent is enriched in .sup.18F. In some cases, an imaging agent including salt forms (e.g., ascorbate salt) may be used to image an area of interest in a subject, including, but not limited to, the heart, cardiovascular system, cardiac vessels, brain, and other organs.

The present invention relates to a polyethylene glycol derivative and a preparation method thereof. A preparation process of a polyethylene glycol derivative, according to the present invention, may provide a novel polyethylene glycol derivative which can be utilized in various ways as a drug linker, and is appropriate and effective for mass production and is advantageous in reproducible mass production of high-quality products.

The present invention relates to a polyethylene glycol derivative and a preparation method thereof. A preparation process of a polyethylene glycol derivative, according to the present invention, may provide a novel polyethylene glycol derivative which can be utilized in various ways as a drug linker, and is appropriate and effective for mass production and is advantageous in reproducible mass production of high-quality products.

The present invention relates to a polyethylene glycol derivative and a preparation method thereof. A preparation process of a polyethylene glycol derivative, according to the present invention, may provide a novel polyethylene glycol derivative which can be utilized in various ways as a drug linker, and is appropriate and effective for mass production and is advantageous in reproducible mass production of high-quality products.

The present invention relates to an N,N′-diurea derivative represented by the following general formula (1) and a method for producing the same. In addition, the present invention relates to a thermosensitive recording material in which a thermosensitive recording layer including a basic dye which is colorless or lightly colored at room temperature and a developer capable of developing color upon contact with the basic dye by heating is provided on a base sheet, wherein the developer is the N,N′-diurea derivative represented by the following general formula (1):

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(wherein R2 is an alkyl group, an aralkyl group, or an aryl group; and A1 is a hydrogen atom or an alkyl group).

The present invention relates to an N,N′-diurea derivative represented by the following general formula (1) and a method for producing the same. In addition, the present invention relates to a thermosensitive recording material in which a thermosensitive recording layer including a basic dye which is colorless or lightly colored at room temperature and a developer capable of developing color upon contact with the basic dye by heating is provided on a base sheet, wherein the developer is the N,N′-diurea derivative represented by the following general formula (1):

##STR00001##

(wherein R2 is an alkyl group, an aralkyl group, or an aryl group; and A1 is a hydrogen atom or an alkyl group).