preferred_name: iodide(out) + chloride(in) => iodide(in) + chloride(out)
preferred_name_lc: iodide(out) + chloride(in) => iodide(in) + chloride(out)
label: iodide(out) + chloride(in) => iodide(in) + chloride(out)
label_lc: iodide(out) + chloride(in) => iodide(in) + chloride(out)