Pyrazinamide - 13 C, 15 N is 15 N and 13 C labeled Pyrazinamide. Pyrazinamide (Pyrazinecarboxamide; Pyrazinoic acid amide) is a potent and orally active antitubercular antibiotic. Pyrazinamide is a proagent that is converted to the active form pyrazinoic acid (POA) by PZase/nicotinamidase encoded by the pncA gene in M. tuberculosis.