Rasagiline- 13 C 3 (mesylate racemic) is a 13 C-labeled Rasagiline mesylate racemic. Rasagiline mesylate racemic is a highly potent selective irreversible mitochondrial monoamine oxidase (MAO) inhibitor. Rasagiline-13C3 (mesylate racemic) is a click chemistry reagent, it contains an Alkyne group and can undergo copper-catalyzed azide-alkyne cycloaddition (CuAAc) with molecules containing Azide groups.