LABELLED COMPOUND

摘要

The present Invention provides a labelled .beta.-cyano-L-alanine and a .gamma.-cyano-.alpha.-aminobutyric acid, of which cyano group carbon is labelled with radionuclids 11C or 14C, or stable isotope 13C. The present invention also provides a labelled amino acids such as asparagine, asparatic acid, DABA, GABA, glutamine and glutamic acid synthesized by using the labelled .beta.-cyano-L-alanine and the .gamma.-cyano-.alpha.-aminobutyric acid as an intermediate. The labelled amino acids are useful for in vivo imaging of tumors and bra in functions.