text: <unk>  is a third-generation cephalosporin antibiotic with specific activity against Pseudomonas aeruginosa. It has no significant activity against other Gram-negative bacteria and very limited activity against Gram-positive bacteria and anaerobic bacteria.<unk>  was first synthesized and patented by the Takeda Pharmaceutical Company in 1977. In 2002, Takeda stopped production of<unk> . Many years of low-stability<unk>  production has led to a widespread reduction of laboratory and research uses. Current attempts (i.e. IDEXX Laboratories) of increasing purity and stability of<unk>  center around recrystallization. Typically, the process entails:<unk>  is dissolved in an organic solvent, sodium ions, water, or any mixture thereof, then subsequently recrystallized through separation of the unwanted fraction. Recently, TOKU-E has found the main cause of<unk>  instability stems from one key impurity in 7-aminocephalosporanic acid, a raw material used in the synthesis of<unk> . To produce high-purity, high-stability<unk> , TOKU-E uses industrial HPLC to remove significant quantities of this impurity in 7-ACA and thus produces ultrapure, ultrastable, and ultrapotent<unk> .
option_0: Cefsulodin
option_1: Meropenem
option_2: Clindamycin hydrochloride 
option_3: Plicamycin
option_4: Vancomycin 
option_5: Azlocillin
option_6: Ertapenem
option_7: Midecamycin