The present invention relates to hyperpolarized [3-.sup.13C]acetoacetate. Provided are [3-.sup.13C]acetoacetate and compositions comprising said [3-.sup.13C]acetoacetate. Further provided are methods of preparing and using hyperpolarized [3-.sup.13C]acetoacetate in the determination of the spatial and temporal distribution and metabolism of [3-.sup.13C]acetoacetate and/or its metabolites in a cell or subject, preferably by magnetic resonance imaging (MRI), magnetic resonance spectroscopy (MRS), and/or magnetic resonance spectroscopic imaging (MRSI), whereby conditions, diseases, or disorders associated with the metabolism of acetoacetate and/or other ketone bodies can be diagnosed. The conditions, diseases, or disorders to be diagnosed preferably are cancer, diabetes, cardiovascular diseases, or neurodegenerative diseases.

The present invention relates to hyperpolarized [3-.sup.13C]acetoacetate. Provided are [3-.sup.13C]acetoacetate and compositions comprising said [3-.sup.13C]acetoacetate. Further provided are methods of preparing and using hyperpolarized [3-.sup.13C]acetoacetate in the determination of the spatial and temporal distribution and metabolism of [3-.sup.13C]acetoacetate and/or its metabolites in a cell or subject, preferably by magnetic resonance imaging (MRI), magnetic resonance spectroscopy (MRS), and/or magnetic resonance spectroscopic imaging (MRSI), whereby conditions, diseases, or disorders associated with the metabolism of acetoacetate and/or other ketone bodies can be diagnosed. The conditions, diseases, or disorders to be diagnosed preferably are cancer, diabetes, cardiovascular diseases, or neurodegenerative diseases.

The invention discloses a method for the preparation of 2-chloro acetoacetic acid amide or ester by a reaction of acetoacetic acid amide or ester with trichloroisocyanuric acid in the presence of amylene and in the solvent acetone.

The invention discloses a method for the preparation of 2-chloro acetoacetic acid amide or ester by a reaction of acetoacetic acid amide or ester with trichloroisocyanuric acid in the presence of amylene and in the solvent acetone.

The invention discloses a method for the preparation of 2-chloro acetoacetic acid amide or ester by a reaction of acetoacetic acid amide or ester with trichloroisocyanuric acid in the presence of amylene and in the solvent acetone.

The invention discloses a method for the preparation of 2-chloro acetoacetic acid amide or ester by a reaction of acetoacetic acid amide or ester with trichloroisocyanuric acid in the presence of amylene and in the solvent acetone.

The invention discloses a method for the preparation of 2-chloro acetoacetic acid amide or ester by a reaction of acetoacetic acid amide or ester with trichloroisocyanuric acid in the presence of amylene and in the solvent acetone.

The present disclosure discloses a novel compound, 3,4-dihydroxyphenethyl 3-hydroxybutanoate, a method for preparing the same and use of the same, and in particular, a compound of formula I, use of the compound of formula I, optically pure isomers of the compound, a mixture of enantiomers in any ratio, or pharmaceutically acceptable salts thereof in preparing health food and drug for relieving brain fatigue, improving learning and memory abilities, and ameliorating mania mood related to brain fatigue.

##STR00001##

The present disclosure discloses a novel compound, 3,4-dihydroxyphenethyl 3-hydroxybutanoate, a method for preparing the same and use of the same, and in particular, a compound of formula I, use of the compound of formula I, optically pure isomers of the compound, a mixture of enantiomers in any ratio, or pharmaceutically acceptable salts thereof in preparing health food and drug for relieving brain fatigue, improving learning and memory abilities, and ameliorating mania mood related to brain fatigue.

##STR00001##

A solution containing a diketone compound having an alkoxy group, a dialkylzinc represented by general formula (1) and/or a partial hydrolysate of the dialkylzinc, and a solvent is described. A method for producing a zinc oxide thin film involves applying the dialkylzinc solution or a solution containing a dialkylzinc partial hydrolysate to a base material.

ZnR.sup.10.sub.2 (1)

In the formula, R.sup.10 is a C.sub.1-6 linear or branched alkyl group. The solution containing dialkylzinc or dialkylzinc partial hydrolysate can be handled in air, making it possible to form a transparent thin film having high adhesiveness to a substrate even with film formation in air.