数据之源，洞见之始

2-hydroxy-2-butenedioic acid

Oxalacetic acid, also known as oxaloacetic acid, keto-oxaloacetate or 2-oxobutanedioate, belongs to the class of organic compounds known as short-chain keto acids and derivatives. These are keto acids with an alkyl chain the contains less than 6 carbon atoms. Oxalacetic acid is a metabolic intermediate in many processes that occur in animals and plants. It takes part in gluconeogenesis, the urea cycle, the glyoxylate cycle, amino acid synthesis, fatty acid synthesis and the citric acid cycle. Oxalacetic acid exists in all living species, ranging from bacteria to plants to humans. Within humans, oxalacetic acid participates in a number of enzymatic reactions. In particular, oxalacetic acid is an intermediate of the citric acid cycle, where it reacts with acetyl-CoA to form citrate, catalyzed by citrate synthase. It is also involved in gluconeogenesis and the urea cycle. In gluconeogenesis oxaloacetate is decarboxylated and phosphorylated by phosphoenolpyruvate carboxykinase and becomes 2-phosphoenolpyruvate using guanosine triphosphate (GTP) as phosphate source. In the urea cycle, malate is acted on by malate dehydrogenase to become oxaloacetate, producing a molecule of NADH. After that, oxaloacetate can be recycled to aspartate, as this recycling maintains the flow of nitrogen into the cell. In mice, injections of oxalacetic acid have been shown to promote brain mitochondrial biogenesis, activate the insulin signaling pathway, reduce neuroinflammation and activate hippocampal neurogenesis (PMID: 25027327). Oxalacetic acid has also been reported to reduce hyperglycemia in type II diabetes and to extend longevity in C. elegans (PMID: 25027327). Outside of the human body, oxalacetic acid has been detected, but not quantified in, several different foods, such as Persian limes, lemon balms, wild rice, canola, and peanuts. This could make oxalacetic acid a potential biomarker for the consumption of these foods.

The trans-2,3-epoxy derivative of succinic acid." []

2,3-Dihydro-5-methyl-3-thiophenethiol is a component of roast meat aroma models. Possesses a rubbery, meaty aroma.

4,5-Dihydro-2-methyl-3-thiophenethiol is a constituent of meat odour model systems. Possesses a roasted meat aroma.

4,5-Dihydro-5-methyl-3-thiophenethiol is a component of meat odour models. Possesses a roasted meat aroma.

A C4-dicarboxylate resulting from deprotonation of both carboxy groups of malic acid." []

An optically active form of malate having (R)-configuration." []

An optically active form of malate having (S)-configuration." []

A choline in which one of the methyl carbons is replaced by an (11)C isotope. An intravenous radioactive diagnostic agent used (in the form of its chloride salt) as a tracer during positron emission tomography scans to help detect sites of recurrent prostate cancer." []

An L-alpha-amino-acid residue derived from S-nitroso-L-cysteine." []