Unnatural amino acid derivative. Pharmacological tool and potential chiral building block used as an internal standard for amino acid analysis. Suitable reagent used for the differentiation of beta-N-methylamino-L-alanine from the diamino acids by using HPLC-FD, UHPLC-UV, UHPLC-MS, and triple quadrupole tandem mass spectrometry (UHPLC-MS/MS). Used in the quantification of neurotoxin beta-N-methylamino-L-alanine (BMAA) in seafood. It has been found to inhibit GABA transaminase (ABAT), producing elevated levels of GABA and to have an antitumor activity.