Azetirelin, as a TRH analog, has a more potent effect than TRH on the central nervous system.

Phenylpyruvic acid is a keto-acid that is an intermediate or catabolic byproduct of phenylalanine metabolism. It has a slight honey-like odor. Levels of phenylpyruvate are normally very low in blood or urine. High levels of phenylpyruvic acid can be found in the urine of individuals with phenylketonuria (PKU) an inborn error of metabolism.

7-Xylosyl-10-deacetyltaxol B is a natural product.