. . . . . . . "1-(4-Tert-Butylcarbamoyl-Piperazine-1-Carbonyl)-3-(3-Guanidino-Propyl)-4-Oxo-Azetidine-2-Carboxylic Acid"@en . . . . . . . . . . . . . . . . . . . . . . "experimental"@en . . . . . .