AIDS-104590 AIDS104590 Cephalosporin fluoroquinolonate deriv S-PETM [3-[(1-methyl-1H-tetrazol-5-yl)thio)methyl]-2-carboxy-8-oxo-thia-1-azabicyclo[4,2,0]oct-2-en-7-yl] ammonium, 1-ethyl-6-fluoro-7-piperazin-1-yl)-1,4-dihydro-4-oxo-3-quinoline carboxylate