(2-(2-Methyl-5-nitro-1H-imidazol-1-yl)ethyl) hydrogen succinate 13182-87-1 Butanedioic acid, mono(2-(2-methyl-5-nitro-1H-imidazol-1-yl)ethyl) ester EINECS 236-130-1 Metronidazole monosuccinate